Care and Prevention of Athletic Injuries of the Knee
and Lower Leg – A Comprehensive analysis

Researched and Composed by Joe “Yu Yevon” King

Abstract: Injuries to the knee and lower leg complex in sport are common, as they are an integral link in the kinetic chain and serve as main weight bearing supports for the upper body. In sports such as football and basketball, as well as in other sports where sharp and swift cutting movements are involved, knee injuries are very common. The initial treatment of such injuries is imperative to the recovery and stability of the affected region. If improper techniques are utilized, the function of the injured area may be compromised, and can lead to impaired athletic performance. The following study reviews various injuries to the lower leg and the knee, as well as reviews the current scientific literature and latest care and prevention techniques. 

Recommended reading in conjunction with this article for full comprehension of topics discussed:  

A Comprehensive Physiological Breakdown of Acute Trauma 

Care and Prevention of Athletic Injuries – The Foot and Ankle Complex 

Anatomy of the Knee Complex 

The knee is one of the most traumatized joints in the human body. This is due in part to its complexity and the heavy and sometimes violent loads placed upon it. The knee is considered to be a hinge joint, as it allows for flexion and extension, but specifically it is a synarthrotic joint because of its ability to allow some degree of tibial rotation. The stability of the knee joint relies primarily on ligaments that surround the joint. Although the knee is very stable anteriorly and posteriorly, it is relatively unstable medially and laterally.  

The knee joint is comprised of four bones; the femur, the patella, the tibia, and the fibula. The distal end of the femur flares out on each side to form the medial and lateral condyles, which articulate with the tibia (on the tibial plateau) and the patella. Anteriorly, the medial and lateral condyles form a hollow groove in which the patella sits.  

Side Note: Although the head of the fibula does not contact the femur or the patella, it is still contained within the synovial joint capsule of the knee, thus the fibular head is considered part of the knee complex.  

The patella is classified as a sesamoid bone, and is the largest of its kind in the body. The patella is held in place by the tendon of the quadriceps and can be divided into three medial facets and one lateral facet that contact the femur.  

While the knee may seem like it is comprised of one large joint, there are multiple articulations within the joint capsule. The articulations occur between the femur and the tibia, the femur and the patella, the femur and the fibula, and the tibia and the fibula.  

Resting atop of the tibia plateau are the medial and lateral menisci structures. The menisci are two oval (semilunar) fibrocartilages that serve to deepen the articular surface of the tibia allowing for a more secure fit of the femoral condyles. The menisci also serve as shock absorbers for the knee. The medial meniscus is shaped like a “C” and is firmly attached to the medial articular facet of the tibial plateau, as well as to the joint capsule via the coronary ligaments. On the posterior aspect of the medial menisci, fibers attach it to the semimembranosus muscle. The lateral meniscus is shaped like an “O” and is loosely attached to the lateral articular facet of the tibial plateau. The blood supply for the menisci structures were briefly outlined in the introductory article linked at the top of this page: 

The meniscus structures of the knee articulation have varying degrees of vascularity. The inner 1/3 of the meniscus structures are avascular, meaning there is no blood supply. The middle 1/3 is partially vascular, and the outside 1/3 is fully vascular.  

During a tear of the meniscus, if the inner 1/3 is damaged, healing will be impossible. As a result, a procedure known as a meniceptomy (removal of part of the meniscus) will be necessary. If the tear occurs on a vascular zone, it will have the capacity to heal (although surgery still may be required to speed up the healing process). (68)

The cruciate ligaments (Anterior Cruciate, Posterior Cruciate) account for a considerable amount of knee joint stability. The Anterior Cruciate Ligament (ACL) attaches below and in the front of the tibia and passes backward to attach laterally o the inner surface of the lateral condyle of the femur. The Posterior Cruciate Ligament (PCL) crosses from the back of the tibia in an upward, forward, and medial direction to attach to the anterior portion of the lateral surface of the medial condyle of the femur.

The ACL is comprised of three separate bands; the anteromedial, intermediate, and posterolateral bands. The ACL prevents the femur from moving posteriorly (posterior translation) and stabilizes the tibia against excessive internal rotation. When the knee is extended, the posterolateral section of the ACL is tight. In knee joint flexion, the anteromedial fibers tighten (104). The PCL works to resist internal rotation of the tibia and prevent hyperextension of the knee and anterior displacement of the femur during weight bearing.

The collateral ligaments of the knee help to direct movement in a correct path, as well as provide much needed medial and lateral stability to the region. The Medial Collateral Ligament (MCL) attaches above the joint line of the knee on the medial epicondyle of the femur and below on the tibia. The main purpose of the MCL is to prevent the knee from valgus and external rotating forces (109). The deep medial capsular ligament is divided into three sections; the anterior, medial, and posterior capsular ligaments. The anterior capsular ligament connects to the extensor mechanism and the medial meniscus through the coronary ligaments. Its primary purpose is to allow the tibia to move on the meniscus inferiorly (7). The Lateral Collateral Ligament (LCL) is a round, fibrous cord that has the thickness of a pencil. It is attached to the lateral epichondyle of the femur and to the head of the fibula.  

The aforementioned articular surfaces are all enclosed in the largest joint capsule of the human body. The joint capsule is divided into four regions; the posterolateral, posteromedial, anterolateral, and anteromedial.  

In order for the knee to function properly, a plethora of muscles must work in synergy with one another. Knee flexion is executed by the biceps femoris, semitendonosus, semimembranosus, gracilis, sartorius, gastrocnemius, popliteus, and the plantaris muscles. Knee extension is executed by the vastus lateralis, vastus medialis, biceps intermedius, and the rectus femoris. External rotation is executed by the biceps femoris. Internal rotation is executed by the popliteal, semitendonosus, semimembranosus, sartorius, and gracilis muscles.

A bursa sack is also present in the joint capsule. A bursa is a flattened sack composed of synovial tissue and fluid. The function of bursa is to reduce friction. As many as two dozen bursa sacks have been found around the knee joint. The knee also contains several fat pads. These pads serve to cushion the front of the knee in order to protect the fragile structures within.

Many nerves cross the knee joint to innervate the architecture below it. The tibial nerve innervates most of the hamstrings and the gastrocnemius. The common peroneal nerve innervates the short head of the biceps femoris and then wraps around the proximal head of the fibula. The femoral nerve innervates the quadriceps and sartorius muscles. Along with nerves, blood vessels and arteries must cross the knee joint as well. The main blood supply for the knee is provided by the popliteal artery, which is a stem from the femoral artery. Five branches of the popliteal artery supply the knee with blood.  

As stated earlier, the knee is an integral part of the kinetic chain and is directly affected by the motions and forces occurring to and being transmitted from the foot, ankle and lower leg. In turn, the knee must transmit forces to the thigh, hip, pelvis and spine.  

Side Note: Footwear is not only important to the foot and ankle complex as discussed in the Care and Prevention Techniques of the Foot and Ankle article; it also effects forces applied up the kinetic chain into the knee and even up to the spine.

Knee Injuries

Medial Collateral Ligament (MCL) Sprain

Ligament injuries of the knee can occur in combination or in isolation. Depending on the application of the forces, a ligament injury can occur from a direct force, a rotary force, or a combination of the two (8). The majority of knee sprains affect the MCL from either a direct blow to the lateral aspect of the knee or from a forceful outward twist. The MCL has fibers that connect to the medial meniscus, so injury to the MCL can also damage the meniscus structure. The LCL, on the other hand, does not have fibers that connect to the lateral meniscus, so when the LCL is damaged, the meniscus is usually in tact. This is why injuries to the MCL are more severe than injuries to the LCL. Some medical authorities suggest that a torn meniscus seldom occurs as a result of initial trauma, rather resulting from past trauma to the MCL.  MCL sprains vary in degree, depending on the position of the knee at the time of injury, past injuries to the knee, the strength of the muscles crossing the joint, the force and angle of trauma, fixation of the foot, and conditions of the playing surface. Full extension of the knee tightens both the MCL and the LCL and is the most stable position of the knee. Full flexion is the most unstable position for the knee. In general, instability increases as flexion increases. In full flexion, the LCL is very unstable, while the MCL still provides some strong stability to the knee joint (60). Suffice to say, the MCL is the primary stabilizer of the knee in knee joint flexion. Mild or moderate strains to the knee can leave the structure relatively unstable and can increase the probability of injury.

The force and the angle of the trauma determine the location and degree of the trauma incurred. As covered in the Care and Prevention of Foot Injuries article, knee injuries also have three grades of severity.

Grade 1 Medial Collateral Ligament Sprain – In a grade 1 sprain, a few ligamentous fibers are torn or stretched. However, the joint still remains stable, with little to no joint effusion (fluid accumulation). There may be some local stiffness and/or point tenderness along the medial aspect of the joint line, but even during minor stiffness, range of motion is still full. After this injury is incurred, the PRICE acronym should be observed for the first 24 hours following trauma. Crutches can be prescribed, but this is usually not the case with a grade 1. Ice may be applied for 5 minutes before activity for the next 48-72 hours. Knee joint rehabilitation techniques should be employed at this time as well. Begin with isometric exercises until the knee can be flexed without pain. Then the stationary bike can be used to integrate the knee back into the kinetic chain of movement. It usually takes about one to three weeks for an athlete to return to normal athletic activity after suffering this injury. When returning to activity, taping or bracing may be necessary for a short time, but these methods should not be heavily relied upon for preventing another injury.

Grade 2 Medial Collateral Ligament Sprain – A grade 2 MCL sprain consists of both microscopic and gross disruption of ligamentous fibers. The structures commonly involved are the MCL and the medial capsular ligament. A complete tear of the deep capsular ligament and a partial tear of the superficial layer of the MCL or a partial tear of both areas can be present in a grade 2 injury. There is usually little instability, but there will be slight laxity of the knee joint in extension, and increases with knee joint flexion. Swelling will be minimal unless the meniscus or ACL has been torn. Extensive swelling in the acute stage of a grade 2 injury may indicate a torn synovial membrane, subluxated or dislocated patella, or an osteochondral fracture. These conditions are much more serious. Moderate to severe joint tightness will also be present in a grade 2; the athlete will be unable to place the heel flat on the ground. A severe loss of range of motion will be present, as well as pain on the medial aspect of the knee. PRICE should be observed immediately and last for 48 to 72 hours. Crutches are mandatory, as well as a three point gait device until the athlete can walk without a limp. Depending on the severity of the injury, a full leg cast may be necessary, but should only be applied for two to five days. Range of Motion exercises should begin immediately following the acute stages of the injury. During rehabilitation, isometric exercises, especially for the quadriceps, should be conducted, as well as closed kinetic chain exercises.

Grade 3 Medial Collateral Ligament Sprain – A grade 3 MCL sprain consists of a complete tear of the supporting ligaments. Some signs of a complete tear include a complete loss of medial stability, minimum to moderate swelling, immediate and severe pain followed by a dull ache, severe loss of range of motion due to effusion, and positive stress tests. Isolated grade 3 MCL sprains occur when a direct force is applied laterally to the knee when the foot is fixated. Grade 3 tears of the MCL due to a rotation movement usually results in ACL and sometimes PCL tears as well (113). The PRICE acronym should be followed for twenty minutes every two hours throughout the day for at least 72 hours. Surgery may be imminent, but new evidence suggests that non-surgical procedures treating an MCL tear where the ACL and PCL are also affected may be more beneficial to knee joint stability than surgical repair. More studies need to be conducted to verify this, however. Rehabilitation programs similar to that of a grade 1 and grade 2 sprain should be initiated, keeping in mind that the recovery times will be much greater.

Lateral Collateral Ligament (LCL) Sprain 

Sprain of the LCL is much less common than sprains to the MCL. Varus forces with the tibia internally rotated will cause this injury. A direct blow to the medial aspect of the knee is rare, so it is usually indirect forces that cause the sprain. If the force is severe enough, the cruciate ligaments, the iliotibial band, and the biceps femoris muscle may be torn. The meniscus structures may be damaged as well. Avulsion fractures can occur on the femur or the tibia, and sometimes on the fibula via a combined pull of the LCL and the biceps femoris on the head of the fibula.  

The collateral ligaments are so strong that they can break the bone before they tear off of it. 

Major signs of an LCL injury include pain and point tenderness over the LCL and palpable deformation when the knee is flexed and internally rotated. Swelling and effusion will also be present over the LCL, as well as joint laxity and degrees of pain. An injury to the peroneal nerve may also be present, causing temporary or sometimes permanent palsy. The common peroneal nerve originates from the sciatic nerve and lies beneath the head of the fibula and winds laterally around the neck of the fibula, where it branches off to form the deep and superficial peroneal nerves. A tear of this nerve can produce weakness and paralysis to the lateral aspect of the lower leg. Management of LCL sprains is nearly identical to that of MCL sprains.  

Anterior Cruciate Ligament Sprain 

An ACL sprain is the most critical ligament injury in the knee (85). When the tibia is externally rotated and the knee is in a valgus position, the ACL is most vulnerable. The ACL can sustain an injury from a direct blow to the knee when the leg is rotated while the knee is fixed. In this position, the ACL becomes taut and susceptible to sprain. Tears of the ACL, combined with injury to other surrounding structures in the knee, can produce rotary instabilities. Anterolateral rotary instability may involve injury to the anterolateral joint capsule, the LCL, and possibly the PCL and structures in the posterolateral corner. Anteromedial rotary instability usually involves injury to the antermedial capsule, the MCL, PCL, and posteromeidal corner (4). A hyperextension from a blow to the front of the knee with the foot planted can tear the ACL and possibly sprain the MCL. Female athletes are much more likely to suffer noncontact ACL injuries than are males (5, 62). C. Bonci indicated that a number of extrinsic and/or intrinsic factors can provide a plausible explanation for this occurrence (20). Extrinsic factors include the level of conditioning, skill acquisition, playing style, the amount of physical preparation and practice, environmental considerations, and types of equipment used. These factors can be somewhat controllable (90). Intrinsic factors involve individual physiological and psychological factors that are much more difficult to control. Femoral condyler notch size, ACL girth, ACL laxity, and lower extremity anatomic malalignment may all relate to an ACL injury, but no medical consensus on their role in ACL injury exists (45). There is also no consensus on whether sex-specific hormones play a role in the increased incidence of ACL injury in female athletes, thus there appears to be no reason to modify activity or restriction from sport of female athletes at any time during the menstrual cycle (45, 51).  

Since the ACL is intimately connected into the kinetic chain, forces acting upon other body parts can have an effect on the ACL. Impact on the foot or heel rather than on the toes during landing from a jump or changing directions while running, awkward running, and biomechanical perturbations may all result in an ACL injury. Deceleration with valgus stress and rotation appears to be the most common mechanism of injury to the ACL. Neuromuscular factors such as joint stiffness, muscle activation latencies, and muscular recruitment patterns are important contributors to the increased risk of ACL injuries in female athletes. Quadriceps activation during eccentric contraction is also considered to be a major factor in ACL injury (118).  

As soon as injury is incurred, a pop or a snap is felt or heard, followed by immediate disability. The knee will feel like it is “coming apart.” Anterior cruciate ligament tears produce rapid swelling at the joint line. Proprioception is also decreased following an ACL injury (117). Even if PRICE is followed immediately, within one to two hours following the initial trauma, swelling becomes prominent and, after six hours, notable hemarthrosis is present (19). After injury, the athlete will be unable to walk without assistance. ACL injuries lead to serious knee instability. Controversy exists among physicians as to how to best treat an ACL rupture, and when surgery is warranted (97, 143). If left untreated, an ACL rupture will lead to severe joint degeneration (63). A decision for or against knee surgery must be based on the athlete’s age, the type of stress applied to the knee, and the amount of instability present (82, 126). Even a simple surgical repair of the ligament may not be adequate in establishing proper joint stability (49). Joint reconstruction surgeries, however, are much more common and much more effective. Transplantation of another ligament or tendon (pes anserinus, semitendonosis tendon, tensor fasciae latae, or patellar tendon) is used in this procedure to replace part or all of the ACL. This surgery requires three to five weeks in braces and four to six months in rehabilitation (126).  It has been suggested that it may take up to two years to regain normal quadriceps muscle function following an ACL reconstruction (116). At the present time, little scientific evidence exists that suggests the use of a functional knee brace, however some physicians still hold to the belief that bracing can provide some protection during activity (14, 93, 131).  

Posterior Cruciate Ligament Sprain 

D. Shelbourne and colleagues refer to the PCL as being the most important ligament in the knee because it provides a central axis of rotation (126). The PCL provides roughly 90% of the total restraining force to straight posterior displacement of the tibia. When the knee is flexed at 90 degrees, the PCL is in its most vulnerable position. A fall with weight on the anterior aspect of the bent knee with the foot in plantar flexion or a hard blow to the front of the knee can cause a tear of the PCL. The PCL can also be injured by a rotational force, which, according to Shelbourne, causes damage to the medial or lateral side of the knee (126). Symptoms of a posterior cruciate ligament sprain include the feeling of a pop or snap in the back of the knee, tenderness and little swelling will be evident in the popliteal fossa, and laxity will be felt during stress tests.  

PRICE should be implemented immediately. Non-operative rehabilitation of grade 1 and grade 2 injuries must focus on quadriceps strengthening. M. Safran et al states that there is much controversy over whether PCL tears should be treated operatively or non-operatively (121). Satisfactory outcomes achieved by non-operative means have been reported (36, 64, 126). However, surgery is sometimes unavoidable (149). Rehabilitation following surgery often takes six weeks of immobilization in extension with full weight bearing on crutches. ROM exercises are begun at six weeks (108). 

Syndesmotic Sprain 

Isolated injuries to the distal tibiofemoral joint are referred to as syndesmotic sprains (83). The anterior and posterior tibiofibular ligaments are found between the distal tibia and fibula and extend up the lower leg as the interosseous ligament. Sprains of these ligaments appears to be more common than previously believed (31). Increased external rotation, or forced dorsi flexion may cause these ligaments to tear as well as causing a severe sprain of the medial and lateral ligament complexes (95, 134). Initial rupture of the ligaments occurs distally at the tibiofibular ligament, as the force of disruption is increased, the interosseous ligament is torn proximally. Severe pain and loss of function will be present in the ankle region. The pain occurs along the anterolateral region of the leg. J. Tauton reminds us that sprains to the syndesmotic ligaments are extremely hard to treat and take months to heal (134). Treatments of these sprains are nearly identical to that of medial or lateral sprains, however, a longer period of immobilization must take place. Return to activity will take much longer than other sprains around the ankle (96).  

Joint Contusions 

A direct blow to any of the muscles crossing the knee joint can result in a temporarily handicapping condition. One of the muscles frequently involved is the vastus medialis muscle, which is highly involved in locking the knee in full extension. Bruises on the vastus medialis may appear to be a knee sprain. Some of these symptoms include severe pain, loss of movement and acute inflammation. Swelling and discoloration resulting from the tearing of muscle fibers and blood vessels will indicate such an injury. If PRICE is observed immediately following injury, the knee will usually return to functional use within 48-hours after the trauma was incurred.

Bruising on the capsular tissue that surrounds the knee joint is associated with muscle contusions and bruises to the periosteum of the bone. Traumatic force applied to the capsular tissue will cause capillary tearing and bleeding, synovial membrane irritation and profuse fluid effusion into the joint cavity, resulting in intraarticular swelling. This effusion occurs slowly, so it is often unnoticed. Scar tissue will develop eventually.

Care of this injury depends on both the exact location and severity of the contusion. PRICE, along with 24 hours rest should be observed. PRICE may last up to 72-hours after the initial trauma. ROM exercises should be introduced when the inflammation subsides. The heat modality can be introduced post 72-hours, but great caution should be used to prevent swelling. If the swelling has not resolved within a week, chronic inflammation may be present in the form of either synovitis or bursitis. 

Peroneal Nerve Contusion 

The peroneal nerve crosses directly behind the underlying neck of the fibula. A kick or blow to the area can cause a compression injury to the nerve. Immediately following impact, local pain from the contusion and from an electric shock will radiate down the anterior portion of the lower leg and into the dorsum of the foot. Paresthesia and numbness along the distribution of the nerve will also be present. Skin abrasions and ecchymosis with tenderness of the underlying peroneal nerve will cause a tingling sensation, which can be relieved with local pressure. Neuropraxia will last only the first few seconds, but if the injury is severe, hypesthesia and weakness of the peroneals and dorsiflexors will persist, possibly leading to a drop foot (as described in Care and Prevention of Athletic Injuries of the Foot and Ankle). Usually, just a minor injury is incurred and the athlete recovers within a few days.  

When the injury is sustained, PRICE should be followed immediately. As soon as the symptoms are gone, the athlete can return to activity, as long as there is no weakness in the peroneals and dorsiflexors. Protective padding may be used to help protect the tender area from further injury after return to activity. 

Meniscal Lesions 

As previously stated, the medial meniscus is much more prone to injury than the lateral meniscus because of the attachment of the coronary ligament. The lateral ligament does not attach to the coronary ligament and is more mobile during knee movement. The medial meniscus is prone to disruption from valgus and torsal forces. A valgus force can cause the knee to adduct, which will tear and stretch the medial collateral ligament. Its fibers twist the medial meniscus outward (12).  

Repeated mild sprains will make the athlete more prone to this injury due to a lessening of ligamentous stability. The most common mechanism of injury is weight bearing combined with a rotary force while the knee is extended or flexed (12). Cutting motions can also cause injury to the medial meniscus. Stretching of the anterior and posterior portions of the meniscus can produce a vertical-longitudinal tear. The lateral meniscus can sustain an oblique tear by a forceful knee extension with the femur externally rotated (19).

Meniscal lesions can be longitudinal, oblique, or transverse. Because of the blood supply (mentioned earlier), tears in the outer one-third of a meniscus may heal over time if tress in the area is kept to a minimum (7). Tears that occur within the midsubstance of the meniscus often fail to heal because of a lack of adequate blood supply (7).

Diagnosis of a meniscal legion is difficult, even for skilled sports medicine physicians. Diagnosis of the injury should be made immediately before muscle spasming and swelling obscure the normal shape of the knee. A meniscal tear may or may not result in an effusion developing gradually over 48- to 72-hours, joint-line pain and loss of motion, intermittent locking and giving way of the knee, and pain when the athlete squats. Once a tear occurs, the ruptured edges harden and may atrophy. Portions of the meniscus can become detached resulting in loose bodies (described below). Chronic meniscal lesions will display recurrent swelling and obvious muscle atrophy. The athlete will have a sense of the knee “collapsing,” a popping sensation, or of an inability to perform a full squat. Such signs usually indicate the necessity of surgical intervention. If the knee is not locked but shows indications of a tear, an MRI may be needed, as well as a diagnostic arthroscopic examination. A knee that is locked in place by a displaced meniscus needs to be unlocked with the patient under anesthesia. A portion of the meniscus may have to be removed if chronic locking occurs. T. Brindle states that surgical management of meniscal tears should make every effort to minimize loss of any portion of the meniscus (24). The meniscus structures are important in shock absorption and in preventing degenerative joint disease.

Post-surgical management for a partial manisectomy (partial removal of the meniscus) does not require bracing and allows partial to full weight bearing on crutches in about two weeks. An athlete can sometimes return to activity within six to fourteen days following surgery. A repaired meniscus, on the other hand, requires immobilization in a rehabilitative brace for five to six weeks. During immobilization, ROM exercises between 0 and 90 degrees should be conducted. Rehabilitation should concentrate on endurance (24).  

Knee Plica 

Dr. T. Blackburn notes that before birth, a child has three synovial knee cavities whose internal walls, at four months, are gradually absorbed to form a single chamber; however, in roughly 20% of all individuals, the knee fails to fully absorb these cavities (15). In adulthood, these septa form synovial folds known as plicae. The most common of these folds is called the infrapatellar plica, which originates from the infrapatellar fat pad and extends superiorly in a fanlike manner. The second most common synovial fold is the suprapatellar plica, located in the suprapatellar pouch. The least common, but the most subject to injury, is the mediopatellar plica, which is bandlike and begins on the medial wall of the knee joint and extends downward to insert into the synovial tissue that covers the infrapatellar fat pad (15). Because most synovial plicae are pliable, most are asymptomatic; however, the mediopatellar plica may be thick, nonyielding, and fibrotic, causing a number of symptoms. The meadiopatellar plica is associated with chondromalacia of the medial femoral condyle and patella.

If the symptoms originate after trauma, the trauma is usually a blunt force or twist when the foot is planted. Recurrent episodes of pseudolocking of the knee when the individual has been sitting for a period of time may be a positive indicator. As the knee passes 15 to 20 percent flexion, a snap may be felt or heard. These symptoms can easily be misinterpreted as a torn meniscus. However, unlike meniscal tears, there is little or no swelling and no ligamentous laxity. Rest, NSAIDs and localized heat are common ways to treat knee plica. If the plica develops into chondromalacia, surgery is required.

Osteochondral Knee Fractures

Sometimes the same mechanisms that cause collateral ligamentous, crucial ligamentous, and meniscal tears can shear off either a piece of bone attached to the anterior cartilage or the cartilage alone. Twisting, a sudden cutting motion, or a direct blow to the knee can cause such a fracture. A snap is heard and the knee gives away immediately following this injury. Swelling tends to be immediate and extensive due to hemarthrosis, and pain is very intense. Surgery must be performed to replace the fragment as soon as possible to avoid degeneration.

Osteochondritis Dissecans 

Osteochondritis dissecans is a painful condition, which involves a partial or complete separation of a piece of articular cartilage and subchondral bone (103). The majority of these fragments (more than 85%) occur in the lateral portion of the medial femoral condyle (29). Lesions will result in normal articular cartilage with dead subchondral bone underneath separated by a layer of fibrous tissue. The cause of this condition is yet to be discovered, but it seems to have a slow onset. Possible factors may include either direct or indirect trauma, skeletal or endocrine abnormalities, a prominent tibial spine impinging on the medial femoral condyle, or a facet of the patella impinging on the medial femoral condyle.  

When osteochondritis dissecans is present, an aching sensation in the knee will be almost constant, as well as recurrent swelling, and an occasional locking sensation. Point tenderness and atrophy of the quadriceps may also be present. Immobilization and usually a cast is prescribed after diagnosis. This allows for resolution of the cartilage and ossification of the underlying bone. This condition may take as long as a year to resolve, and surgery may be the best way to correct the injury. 

Loose Bodies Within the Knee 

Osteochondral fragments, or loose bodies, can develop within the joint cavity due to repeated injury to the knee. Loose bodies, also called joint mice, can stem from osteochondritis dissecans, menisci fragments, pieces of torn synovial tissue or a torn cruciate ligament. The loose body can move around in the joint and become lodged, causing a locking or popping sensation. Pain and instability may be present. If the loose body becomes lodged in between articulating surfaces, irritation will occur. Joint degeneration can occur if the loose body is not surgically removed. 

Bursitis 

Bursitis of the knee, as well as in other body regions, can be classified as acute, chronic, or recurrent. As mentioned earlier, nearly two dozen bursa sacks have been identified around the knee, however, the prepatellar, deep infrapatellar, and suprapatellar bursa are the most likely to become inflamed in sports. Overuse of the patellar tendon is the most common cause of bursitis at the knee. Localized swelling will be present above the knee. Since the swelling will occur outside of the joint capsule, skin discoloration and increased localized temperature.  

Ceasing activity that irritates the bursa, and techniques aimed to reduce inflammation (PRICE) should be used to treat bursitis. Arguably the two most important modalities for treating bursitis are the use of a compression wrap and NSAIDs. If chronic bursitis is the condition, injected antiinflammatories may be used. 

Patellar Fracture 

Fractures of the patella are not unlike fractures of other bones in that they can occur from both direct or indirect trauma applied to the bone. Most patellar fractures are acquired by indirect means consisting of a sudden and forceful pull on the patellar tendon against the femur when the knee is partially flexed. In this position, maximum stress is placed on the bone from the quadriceps and the patellar ligament. Direct injury often produces fragmentation with little displacement. In other words, the patella is likely to crack (shatter) rather than snap. Falling, jumping, or running activities may result in a fractured patella.  

Side Note: Oddly enough, roughly three percent of the population have what is known as a bipartite patella. This means that the patella consists of two portions, rather than just one. When X-rayed, this condition, which is in no way harmful, can be misdiagnosed as a patellar fracture.  

A fractured patella causes hemorrhaging and joint effusion, which causes swelling. Indirect fractures cause a tear in the joint capsule, separation of bone fragments, and possible tearing of the quadriceps tendon. In a direct injury, little bone separation is present. The separated patellar fragments can be easily palpated, and an X-ray will confirm the extent of the injury. In the acute stage, PRICE should be followed with splinting (this goes under “protection”). Immobilization for two to three months is expected.

Patellofemoral Stress Syndrome 

This condition results from lateral deviation of the patella as it tracks in the femoral groove (as mentioned earlier in this publication). W. Prentice and colleagues identified several factors that may cause lateral tracking: Tightness of the hamstrings and gastrocnemius, tightness of the lateral retinaculum (which compresses the lateral facet of the patella against the lateral femoral condyle), increased Q angle (angle made between the head and shaft of the femur), tightness of the iliotibial band, pronation of the foot, patella alta (lengthening of the patellar tendon, making it longer than the patella itself), vastus medialis oblique insufficiency caused by imbalance with the strength of the vastus lateralis or by inhibition resulting from the presence of 20 to 30 ml of effusion in the knee (9), and weak hip adductors to which the vastus medialis oblique attaches (109).  

Tenderness on the lateral aspect of the patella will be present as well as some swelling associated with irritation of the synovium as well as reports of a dull ache in the center of the knee. Patellar compression will elicit pain and crepitus. W.R. Post cautions us that the causes underlying patellofemoral pain as identified during the evaluation process should provide the basis for treatment (105). A strengthening program should be started for the adductor muscles and for correcting the imbalance made between the vastus medialis oblique and the vastus lateralis through the use of biofeedback techniques (72, 88). Stretching of the hamstrings, gastrocnemius and iliotibial band should also be implemented (107). W. Gilleard reports that foot orthotics can be used to correct pronation and other malalignments, as well as specific taping techniques (39). Taping can be used to help correct the orientation of the patella (107). In extreme cases, lateral retinacular release can be used. 

Osgood-Schlatter Disease and Larsen-Johansson Disease 

These two conditions are common to adolescent athletes. Osgood-Schlatters disease is an apophysitis characterized by severe pain at the attachment of the patellar tendon into the tibial tubercle. Thus, an avulsion fracture of the tibial tubercle will be present. The fragment starts off as being cartilaginous, but with growth a bony callus forms and the tuberosity enlarges. This condition usually resolves itself once the adolescent finishes puberty, and the only remnant is an enlarged tubercle.

Although several mechanisms have been postulated, the most widely accepted cause of this disease is by repeated avulsion of the patellar tendon at the apophysis of the tibial tubercle. In severe cases, a complete avulsion may be present.  

Larsen-Johansson disease is very similar to Osgood-Schlatter disease, but it occurs at the inferior surface of the patella. The mechanisms of the onset of this disease is the same as that of Osgood-Schlatter disease. Swelling, pain, and point tenderness are all characteristics of this disease, as well as degeneration of tendonous fibers. Repeated irritation will cause swelling, hemorrhage, and gradual degeneration of the apophysis as a result of impaired circulation. Severe pain will be present with knee flexion, with point tenderness over the anterior proximal tibial tubercle. Management of both diseases is usually very conservative. Some treatments include a decrease in stressful activities until epiphyseal union takes place (six months to a year), a cylindrical cast (in severe cases), ice applied before and after activities, and isometric strengthening of the quadriceps and hamstring muscles. 

Patellar Tendinitis 

Jumping, kicking and running places great stress on the knee extensor muscle complex. As a result, tendinitis can occur in the patellar tendon or quadriceps tendon (11). In some cases, the patellar tendon can completely tear from the bone. Chronic inflammatory conditions of the area may predispose an athlete to a tear or rupture. Tenderness and pain will be present on the inferior surface of the patella, as well as the posterior surface. There are three stages of pain associated with patellar tendinitis.

Stage 1 – Pain immediately following activity.

Stage 2 – Pain both during and after activity, but the athlete is still able to perform adequately.

Stage 3 – Pain both during and after activity, but lasting a long duration. Athletic performance is compromised and may progress to constant pain and eventual rupture.

Any pain in the patellar tendon indicates a sudden, forceful movement that would lead to the pain. J.K. Wilson states that many different approaches have been reported to treat this inflammatory condition including the use of ice, phonophoresis, iontophoresis, ultrasound, and various forms of superficial heat modalities such as whirlpool coupled with a rehabilitation program (146). Bracing may also be used. G. Pellecchia reported that a deep transverse friction massage has been a successful modality of treatment for patellar tendinitis (102). The friction is created via a firm massage of the patellar tendon on the inferior surface of the patella perpendicular to the direction of the fibers. A friction massage is actually used to increase the inflammatory response as to speed healing and push the body into the fibroblastic repair phase. Therefore, when the transverse friction massage modality is used, techniques designed to reduce inflammation should not be used.

Patellar Tendon Rupture 

A rupture of the patellar tendon can be caused by a sudden and powerful contraction of the quadriceps muscle group with weight bearing (130). The rupture may occur in either the patellar tendon or the tendon of the quadriceps. This rupture usually only occurs during a chronic inflammatory condition of the tendons involved where tissue degeneration has taken place. Ruptures, in general, rarely occur in the middle of the tendon, rather at their insertion to the bone. If the patellar tendon is ruptured, the rupture will occur on the inferior portion of the patella, whereas if the quadriceps tendon is ruptured, the rupture will occur on the superior portion of the patella. When the tendon is ruptured, it moves upward toward the thigh creating an obvious deformity. Knee extension is not possible, and there will be excessive swelling present as well as extreme initial pain followed by a minor dull ache.

A rupture of the patellar tendon most likely will require surgical repair. Jumper’s knee may lead to this injury, thus proper care of that condition may reduce the risk of acquiring a rupture. Steroid users are also susceptible to this injury (case in point, Markus Ruhl). Steroids injected directly into these tendons weaken collagen fibers and mask pain (131).

Acute Patellar Subluxation or Dislocation

Forced knee valgus can occur when the thigh rotates internally while the lower leg rotates externally (this often occurs during deceleration and cutting movements when the foot is planted). If this occurs, the quadriceps attempts to pull in a strait line, thus pulling the patella laterally which may dislocate the bone. The patella always displaces laterally under these conditions. Some athletes may be prone to this injury if they have a wide pelvis with anteverted hips, genu valgum (which increases the Q angle), shallow femoral grooves, flat lateral femoral chondyles, flat patellas, vastus medialis and ligamentous laxity with genu recurvatum and externally rotated tibias, pronated feet and externally pointing tibias.

Pain, swelling and a complete loss of knee function, as well as a obvious deformity may all be present in the acute stage of injury. The dislocation must be reduces immediately  by placing mild pressure on the patella with the knee extended. The PRICE acronym should then be implemented, with emphasis on ice and splinting. If this is a first-time occurrence, a fracture may be present. During treatment, the knee will need to be immobilized for at least four weeks. During this period, isometric exercises can be performed. Horseshoe padding and bracing should be used upon return to activity. Muscles of the thigh and hip should be performed, especially strait leg raises. In some cases, surgery may be required.

Injury to the Infrapatellar Fat Pad

The infrapatellar fat pad aids in protection and shock absorption of the knee. It lies between the synovial membrane on the anterior aspect of the joint and the patellar tendon. The infrapatellar fat pad is particularly vulnerable during athletic activity, and can be injured if wedged between the tibia and patella, irritated by chronic flexion pressures, or via a direct blow. Capillary hemorrhaging can be present due to repeated trauma and localized swelling. If the irritation continues, scaring and calcification may develop. Pain may be present below the patellar ligament during knee extension, and the knee may become weak with mild swelling and stiffness.

Rest from activities, which irritate the area, heel elevation, and ice modalities should be utilized to treat acute injury. Hyperextension taping may also be necessary to prevent against full extension.

Chondromalacia Patella

Chondromalacia patella is a softening and deterioration of the articular cartilage on the backside of the patella. Chondromalacia can be identified in three separate stages.

Stage 1 – Swelling and softening of the articular cartilage.

Stage 2 – Fissuring of the softened articular cartilage. 

Stage 3 – Deformation of the surface of the articular cartilage caused by fragmentation. 

To date, the cause of chondromalacia is unknown. Some experts suggest abnormal patellar tracking may be a factor, however individuals with normal tracking have sustained this condition, and others with abnormal tracking are free of it (9). Pain on the anterior aspect of the knee while walking, running, ascending and descending stairs or squatting will be present. Recurrent swelling around the patella will be seen, and a grating sensation will be felt during knee flexion and extension. Palpable pain will also be present on the inferior border of the patella and when the patella is compressed within the femoral groove during passive flexion and extension. One or more alignment deviations may also signal the presence of chondromalacia.  M. Baker reported degenerative arthritis on the medial facet of the patella, which makes contact with the femur when the athlete performs a squat (9). Both Baker and A. Boland report that degeneration first occurs in the deeper portions of the articular cartilage, followed by blistering and fissuring that stems from the subchondral bone and appears on the surface of the patella (9, 19).  

Conservative treatments include avoidance of activities which irritate the area, isometric exercises for the quadriceps and hamstring muscles, NSAIDs and small doses of aspirin, a knee sleeve, an orthotic device used to correct pronation and reduce tibial torsion. Boland states that if these measures fail, surgery may be the only option (19). Surgical procedures include moving the insertion of the vastus medialis muscle forward through realignment procedures such as lateral release of the retinaculum, shaving and smoothing the irregular surfaces of the patella and femoral condyle, removing the blister with drilling, elevating the tibial tubercle, and as a last resort completely removing the patella (BOLAND). 

Runner’s Knee 

Runners knee is a general term used to define overuse injuries of the knee. Malalignment and structural asymmetries of the leg and foot can cause an overuse condition. Patellar tendinitis and patrellofemoral conditions may led to chondromalacia. Two conditions that are common among distance athletes are iliotibial band friction syndrome and pes anserinus tendinits or bursitis. Iliotibial band friction syndrome is an overuse injury, which is common in distance athletes who have genu varum and a pronated foot (112). Irritation develops at the bands insertion point and on the lateral condyle of the femur. Treatment for this condition consists of stretching and iliotibial band and reducing inflammation (112).  

The pes anserinus is the location where the gracilis, sartorius, and semitendonosus muscles attach to the tibia. Pes anserinus tendinitis and pes anserinus bursitis go hand in hand with one another. Inflammation can result from a weak vastus medialis muscle. Running on a slope with one foot higher than the other over time can cause this condition.  

Alignment problems must be corrected in order to help correct this condition. Acute treatment includes ice and a deep tissue massage before and/or after activity as well as a proper warm-up with stretching. It is also important to avoid activities that aggravate the condition, such as running on an incline. NSAIDs and foot orthotics may help reduce the condition as well. 

Prevention of Knee Injuries 

Prevention of knee injuries is a multi-dimensional task. Of major influence are effective physical conditioning, rehabilitation and skill development, and even shoe type. To avoid knee injuries, athletes must be highly conditioned, which includes total body conditioning that includes strength, flexibility, cardiovascular and muscular endurance, agility, speed and balance (110). The muscles surrounding the knee joint must be both strong and flexible. A proper strength ratio between the quadriceps and hamstrings must be maintained. For example, the hamstrings should have 60 to 70% of the strength of the quadriceps (110). The gastrocnemius should also be strengthened to aid in knee stabilization. It is important to remember, however, that while increasing muscle strength may prevent some injuries, it fails to prevent rotary-type injuries. It should be noted that avoiding abnormal muscular contraction through flexibility exercises is a necessary protection for the knee. The extensibility of the hamstrings, erector spinae, groin, quadriceps and gastrocnemius muscles are of primary focus. Lastly, when a minor knee injury is incurred, proper rehabilitation must take place. Repeated minor injuries make the knee susceptible to a major injury.  

A proprioceptive balance board or a stability ball training program is suggested to improve neuromuscular control and both static and dynamic balance. Jump-landing training is also suggested. Many athletes injure their knees due to landing improperly from a jump. Jump-landing occurs in all functions (running, pivoting and jumping). 

Proper shoes should also be worn. See the Care and Prevention of Athletic Injuries of the Foot and Ankle complex for more on proper footwear.  

Knee braces are designed to prevent or reduce the severity of an injury (131). The effectiveness of knee bracing is very controversial in sport today (109, 122). It is generally accepted that knee braces have little or no effect on functional performance measures (43, 109). 

Lower Leg Injuries*

*Note that most injuries of the ankle are included in the Care and Prevention of Athletic Injuries of the Foot and Ankle article. Injuries to the Achilles are included in this article.

Eversion Ankle Sprains

In the last article, inversion ankle sprains were covered, but there is also a possibility of sustaining a eversion ankle sprain, however this is much less common (only about 5 to 10% of all ankle sprains). The difference in the occurrence between the two sprains is largely due to the bony architecture and ligamentous anatomy of the area affected. The strength of the powerful deltoid ligament prevents excessive eversion of the foot. S. Hunter and colleagues remind us that often times eversion ankle injuries also involve an avulsion fracture of the tibia (59). The deltoid ligament is so powerful, it will rip apart the bone before breaking. Even though eversion ankle sprains are much less common, they take much longer to heal. A foot that is pronated, hypermobile, or has a flattened medial longitudinal arch may be more susceptible to an eversion ankle sprain (17). When this injury is sustained, pain will be severe over the foot and the lower leg. Weight bearing will most likely not be possible at this time. Both adduction and abduction of the foot will illicit pain, but pressing upward against the bottom of the foot will not produce pain.

X rays will be necessary to assess whether a fracture is present or not. In the acute stages, PRICE should be followed, and a posterior tape splint should be applied. Management for this injury will be the same as that of inversion sprains.

Acute Achilles Tendon Strain

Achilles tendon strains are very common and usually occur after a sudden dorsi flexion of the foot. This injury can be mild to severe. Severe injury is classified as a partial or complete avulsion or rupturing of the Achilles tendon. Acute pain and extreme weakness during plantar flexion will indicate a rupture. The PRICE acronym must be followed immediately. After the hemorrhaging subsides, a wrap should be applied to continue pressure. It is easy for this injury to turn into a chronic condition (discussed in the previous article), therefore a conservative approach is required. Stretching and strengthening of the heel chord should begin as soon as tolerated. A heel lift should also be used to decrease tension on the tendon, which will help to prevent chronic inflammation (Achilles tendinitis).

Achilles Tendon Rupture

Achilles tendon ruptures are most common in older athletes, but can occur at any age (74). If the athlete has a history of chronic inflammation and gradual degeneration caused by microtears in the tendon, a rupture may be likely (3). A sudden pushing off action of the forefoot with the knee forced into complete extension is the most common cause of this injury. When rupture occurs, a sudden, loud, and forceful snap is heard and felt. Pain is immediate, but subsides rapidly. Swelling, point tenderness, and discoloration will be present. Toe raising will be structurally impossible in an Achilles tendon rupture. Ruptures occur only two to six centimeters proximal to its insertion onto the calcaneus bone. D. Dugan and colleagues state that surgery is usually required (33). Non-surgical treatment includes PRICE, anti inflammatory medications, and analgesic medications along with a non weight bearing cast for six weeks followed by a short leg walking cast for two more weeks. Using the non-surgical approach, there is a 75% to 85% return to normal function (17). With surgery, up to 90% return to normal function may be obtained. Rehabilitation usually lasts about six months and consists of ROM exercises, progressive resistance exercises, and wearing a heel pad in both shoes (17).

Leg Cramps and Spasms

Spasms are classified as sudden, violent, involuntary contractions of one or more muscles and may be either tonic or clonic. A Tonic spasm is identified by constant muscle contraction without an intervening period of relaxation. A clonic spasm is identified by intermittent contraction and relaxation. The clonic spasm results from neurological conditions, and is not common in sports. The exact cause of muscle cramps is difficult to determine. Fatigue, dehydration, and inadequate reciprocal muscle coordination are some factors, which may lead to a tonic muscle spasm. The gastrocnemius muscle is the most common location for such a spasm. Relaxation must take place to relieve the muscle cramp. Grasping the affected muscle firmly with mild and gradual stretching can relieve the acute spasms. Ice coupled with massage can help in reducing the spasm as well. In the case of a recurrent spasm, the athlete should increase his or her water and electrolyte intake.

Gastrocnemius Strain

The medial head of the gastrocnemius is susceptible to muscle strains near its musculotendinous attachment. Quick acceleration and deceleration can cause a strain. This injury usually occurs when the athlete makes a quick stop with the foot planted and then extends the knee, which places stress on the medial head of the gastrocnemius. Depending on the grade of injury, pain, swelling and muscle instability will be present. Many athletes describe the pain as being hit in the calf without any contact actually taking place. Edema, point tenderness and functional strength loss will also be present (21). Initially, PRICE with NSAIDs should be utilized. A grade 1 calf strain should be given a gentle stretch after muscle cooling. Weight bearing can take place when tolerated. A heel wedge may be used to reduce the stretching of the medial gastrocnemius during walking. An elastic wrap may be used upon return to activity, and a rehabilitation program consisting of ROM exercises and progressive resistance exercises should be instituted.

Acute Leg Fractures

Fibular fractures are the most common fractures to the lower extremity. The fracture usually occurs in the middle one third of the shaft, while fractures on the tibia usually occur in the lower one third. These fractures can result from both indirect or direct trauma. Bony displacement with an obvious deformity will be present and is rather grotesque. Crepitus and loss of limb function are present. This injury will also cause a soft tissue insult and massive hemorrhaging. Severe pain and disability is imminent. The leg will appear hard and swollen which may indicate the early stages of Volkmann’s contracture, which is a result of internal tension caused by hemorrhaging and swelling within the closed fascial compartments. This condition will also inhibit blood supply and results in necrosis of muscles and contractures. Fracture reduction and cast immobilization are applied for up to six weeks, depending on the extent of injury and complications.

Peroneal Tendon Subluxation/Dislocation

The peroneus longus and brevis tendons pass through a common groove, which is located behind the lateral malleolus. The peroneal retinaculum hold them into place. Dynamic forces to the foot and ankle will cause this injury to occur. Wrestling followed by football, ice skating, skiing, basketball and soccer have the highest incidence of injury. Another mechanism of injury is a direct blow to the posterior lateral malleolus. A severe inversion ankle sprain or a forceful ankle dorsi flexion can tear the peroneal retinaculum, allowing the peroneal tendon to dislocate. During running or jumping after sustaining this injury, the peroneal tendons snap out of the groove and then back into place when the stress is released. Reoccurring pain, snapping sensations and ankle instability will all be present. Ecchymoses may be present on the lateral aspect of the ankle, as well as edema, tenderness, and crepitus over the peroneal tendon. Compression wraps should be placed over the lateral malleolus, and reinforced with a rigid plaster splint until the acute signs have decreased. PRICE, NSAIDs, and analgesics should be used. The athlete can return to activity after about five to six weeks along side of a rehabilitation program that includes ROM exercises, progressive resistance exercises, and proprioceptive training. If this approach fails, surgery is required.

Anterior Tibialis Tendinitis

This condition is common amongst running athletes and is often misdiagnosed as “shin splits,” which is a grossly overused and general term for any pain relating to the anterior portion of the lower leg. Point tenderness over the anterior tibialis will be present. Rest, or at leased a decrease in activity, should be implemented, as well as an avoidance of running on hills. In some cases, ice and stretching should be conducted both before and after activity. A strengthening program should be conducted and anti inflammatory medications may be necessary (123).

Posterior Tibial Tendinitis

Posterior tibialis tendinitis is a very common overuse condition among runners with pronated or hypermobile feet (37). Pain and swelling in the area of the medial malleolus will be present, as well as edema and point tenderness directly behind the medial malleolus (inner ankle). If the pain becomes too intense during resistive inversion and plantar flexion, the condition is considered serious (37). PRICE and NSAIDs should be used, and possibly a non-weight bearing short-leg cast with the foot in constant inversion may be needed. Taping and an orthotic device can help correct this condition. 

Peroneal Tendinitis 

This injury can be a problem in athletes with a pes cavus foot. In pes cavus (claw foot), the foot tends to supinate excessively which causes weight bearing on the outside of the foot rather than distributed inward thus placing stress on the peroneal tendon. Pain behind the lateral malleolus while pushing off with the foot will be present. Point tenderness over the peroneal tendon will be present at the lateral aspect of the calcaneus distally to beneath the cuboid bone (79). PRICE should be implemented as well as anti inflammatory and analgesic medications. Taping, and proper warm-up and flexibility exercises should be used before activity. Foot orthotics may help with excessive supination. 

Shin Contusion 

The shin, or specifically the anterior aspect of the lower leg, does not contain much subcutaneus tissue to protect the tibia, which makes the tibia susceptible to contusion injuries. The periosteum of the bone (the outer wrap) receives the brunt of the force applied to the shin. The periosteum contains nerves, blood vessels and bone forming osteoblasts. Intense pain will be felt over the area of the contusion. A hematoma will form rapidly and tends to exhibit jelly-like consistency (37). In severe cases, a tibial fracture may be present. PRICE, NSAIDs and analgesics are used as needed. Maintaining compression on the area of the hematoma is critical. Once pain subsides, ROM exercises and progressive resistance exercises can begin. Doughnut padding under an orthoplast protective shell can prevent the area from further injury during activity (37). If the aforementioned guidelines are not followed, the injury to the periosteum may develop into osteomyelitis, a serious condition that results in the destruction and deterioration of the tibia. Because of this, even minor contusions should not go unattended. 

Muscle Contusions 

Contusions of the leg, particularly in the gastrocnemius muscle, are common in sports. These contusions often occur from being kicked in the back of the leg. A bruise on this area can produce severe pain. Pain, weakness and partial loss of function will occur. Palpation of the area (feeling with the fingers) may reveal a hard, rigid, and inflexible area because of hemorrhage and muscle guarding. When the contusion occurs, it is advisable to stretch the muscles in the region immediately to prevent a muscular spasm. A compression wrap and ice should then be used to control hemorrhaging. If PRICE is ineffective over the next 48- to 72-hours, the ultrasound modality may be utilized. Upon return to activity, an elastic wrap may be applied to protect the area.

Compartment Syndromes 

The lower leg is composed into four compartments, each bound with fascial sheaths. Compartment syndromes have two classifications: acute traumatic or chronic exertional. Acute traumatic compartment syndromes are rather rare and occur after being kicked or after exercise in an untrained individual. Excessive swelling within the fascial compartment can compress muscles, nerves and blood vessels. With an increase in fluid pressure, muscle ischemia that could lead to permanent disability may occur. This is a medical emergency!  

A chronic exertional compartment syndrome occurs frequently among runners and triathletes. In normal conditions, internal pressure within the lower leg compartments rise slowly during exercise and subside after the exercise has ceased (16). Chronic exertional compartment syndrome occurs when the internal pressure builds too high and remains elevated after activity causing ischemia and pain, but neurological involvement is rare (16). Compartment syndromes, especially anterior compartment syndrome, is all too often misdiagnoses as shin splints, and can sometimes be confused with a stress fracture. The anterior compartment has the highest rate of injury than any other compartment of the lower leg (78). The most common chronic exertional compartment syndrome symptoms are bilateral, this incidence ranges from 50% to 60% (27). Symptoms include pain during exercise in the anterolateral region of the leg. Over time, pain will occur in a predictable manner after running a specific distance or duration of time. An ache or a sharp pain and pressure in the region of the anterior compartment when performing a particular activity will be present. These symptoms will go away during rest. Sometimes with more severe cases, pressure and weakness will be felt in foot and toe extension and numbness in the dorsal region of the foot. Initial symptoms can be aided by using PRICE and anti inflammatories. Recurrent conditions may require surgical release (cutting of the fascia to make more room).

Stress Fractures of the Tibia/Fibula 

Stress fractures of the tibia and fibula are common overuse injuries of the lower leg, especially among distance athletes. Structural deformities in the foot may make some athletes more prone to this injury. Hypermobile or pronated foot conditions make an athlete more susceptible to a fibular stress fracture, while those with a pes cavus foot are more susceptible to a tibial stress fracture. More often, stress fractures occur in inexperienced or nonconditioned individuals (133). Training errors are often the cause (133).

The athlete will complain of pain in the lower leg that is more intense after the activity rather than during the activity. Point tenderness may be present. Diagnosis of a stress fracture is very difficult, stress fractures may not show up on an X ray for several weeks, thus a bone scan will be a better tool. Treatment of stress fractures include rest for at least 14 days, crutching or sometimes casting may be used if the athlete is in severe pain, and weight bearing activities can slowly resume after the pain subsides. Cycling or pool training may be a good change of medium while rehabilitating a stress fracture, and this also keeps the athlete conditioned. After pain subsides for two weeks, running may begin again (38).  

Prevention of Lower Leg Injuries 

Many injuries to the lower leg can be prevented or minimized with proper athletic conditioning. Regular stretching of the Achilles tendon, strengthening of key muscles, developing neuromuscular and proprioceptive control, wearing proper footwear and in some cases being properly taped can minimize the risk of a lower leg injury (136).

The Achilles tendon should allow at least ten degrees of dorsi flexion (preferably more). A tight heel cord will limit the range of motion and make an athlete more susceptible to injury. Routine stretching of the Achilles tendon should occur both before and after activity (91). The stretches should be performed both with the knee extended to emphasize the gastrocnemius and with the knee flexed to 15 to 30 degrees to emphasize the soleus.

Just as important to lower leg stability is the strength of the lower leg muscles. Static and dynamic stability are an integral part of injury prevention. A normal range of motion should be maintained, and the muscles and tendons surrounding the talocrural joint must be kept strong.  

Athletes must also develop neuromuscular control. Neuromuscular control involves the capability of adapting to uneven surfaces by controlling motion about the ankle joint. Balance board training and other balance techniques (both static and dynamic) are effective ways to enhance neuromuscular control.

Like bracing, taping is a controversial technique when used as a prevention tool. There is some indication that tape, if properly applied, can provide some prophylactic protection (47, 114). However, tape constricts the soft tissue surrounding the area and can disrupt normal biomechanical function. There are some indications that unnecessary taping can increase the risk of injury. Lace-up supports and semirigid braces are beginning to be used in place of tape (23). Orthotic devices have been found to be superior to taping (77, 78).

Side Note: It is imperative that bracing, taping, or wrapping  between the ankle and the knee should not be done. Ankle and knee braces and wrapping is fine, but such devices placed on the shins will compress the already packed area may inhibit blood flow and muscle function which will increase the risk of injury. 

Conclusions

As we travel up the kinetic chain, it is evident that the body’s individual components are all inter related to one another. What affects the foot also affects the hips and low back and so on. Thus, it is imperative that proper care and prevention of certain injuries and abnormalities take place in order to keep athletes competing to their full potential. Further, minor injuries that are left untreated have been shown to lead to much more serious conditions that may be permanently damaging to the athlete, not only mentally, but psychologically (this will be discussed in a later issue). The better an athlete is able to diagnose an injury, the sooner rehabilitation and treatment procedures can take place.

Keep it Hardcore!

Joe “Yu Yevon” King

Administrator of Hyperplasia Research

YuYevon@abcbodybuilding.com

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