Which type of injury may lead to a strain in the lateral ligament of the knee?
The lateral collateral ligament (LCL) or fibular collateral ligament, is one of the major stabilizers of the knee joint with a primary purpose of preventing excess varus and posterior-lateral rotation of the knee. Although less frequent than other ligament injuries, an injury to the lateral collateral ligament (LCL) of the knee is most commonly seen after a high-energy blow to the anteromedial knee, combining hyperextension and extreme varus force. The LCL can also be injured with a non-contact varus stress or non contact hyperextension. The LCL most commonly occurs in sports (40%) with high velocity pivoting and jumping such as soccer basketball, skiing, football or hockey. Tennis and gymnastics have been shown to have the highest likelihood of an isolated LCL injury.[1] Show The LCL can be sprained (grade I), partially ruptured (grade II) or completely ruptured (grade III) .[2] The LCL is rarely injured alone and therefore additional damage of the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), and posterior-lateral corner (PLC) is common along with the LCL when the lateral knee structures are injured[1] [2][3]. The LCL is a cord-like structure of the arcuate ligament complex, together with the biceps femoris tendon, popliteus muscle and tendon, popliteal meniscal and popliteal fibular ligaments, oblique popliteal, arcuate and fabellofibular ligaments and lateral gastrocnemius muscle[3][4]. The LCL is a strong connection between the lateral epicondyle of the femur and the head of the fibula, with the function to resist varus stress on the knee and tibial external rotation and thus a stabilizer of the knee. When the knee is flexed to more than 30°, the LCL is loose. The ligament is strained when the knee is in extension.[2] See LCL anatomy for more detailed anatomy. In the United States, 25% of the patients who present to the emergency room with acute knee pain have a collateral ligament injury. Adults aged between 20-34 and 55-65 years old have been shown to have the highest incidence. Of the collateral ligament injuries, MCL injuries are more commonly seen over LCL injuries. Limited studies have shown that isolated LCL injuries occur more often in women and in high contact sports[1]. Characteristics/Clinical Presentation[edit | edit source]Acute Patients with an acute LCL injury will present with a history of an acute incident which most commonly consisted of a blow to the medial knee while in full extension or extreme non contact varus bending. Pain, swelling and ecchymosis are often present at the lateral joint line along with difficulty in full weight bearing. Less common complaints consist of a thrust gait, foot kicking during mid stance, paresthesia down the lateral lower extremity as well as weakness and/or foot drop.[1][2] Upon evaluation, a patient with an acute LCL injury may present with reduced ROM, instability/giving way during weight bearing as well weakness of the quadriceps (inability to perform a straight leg raise). The patient will present with pain as well as increased carbs movement when performing a Varus Stress Test.[2] Sub-Acute Patients who present with a sub-acute LCL injury will present with lateral knee pain, stiffness with end of range flexion or extension, overall weakness and possible instability/giving way. Chronic Patients with a chronic LCL injury will present with unspecific knee pain, significant weakness throughout the entire kinetic chain as well as potential instability and mal-adaptive movement patterns[4]. Due to its close proximity to surrounding structures, LCL injuries often occur along with other ligamentous injuries, including ACL, PCL, and PLC, and is frequently seen along with knee dislocations. Although not as common, meniscal tears/injuries can also occur with an LCL injury. Other diagnoses such as a Popliteus avulsion, Iliotibial Band Syndrome, and Distal hamstring tendinopathy need to be ruled out. [3] Information gathered during a subjective assessment will provide vital information necessary to making a diagnosis. Performing a comprehensive physical exam will allow the clinician to make the most appropriate differential diagnosis. Upon observation, patients with a suspected LCL injury will present with swelling, ecchymosis and possible increased warmth along the lateral joint line. A full ROM assessment should be performed as well as careful consideration to palpation along the lateral joint line. When possible, a gait analysis should be performed to identify the classic 'varus thrust' finding that is common in LCL injuries. An isolated LCL injury is uncommon therefore special tests should be performed to determine associated ligamentous, meniscal, or soft tissue injuries.[1] Objective Assessment:
Special Tests:
*Due to the likelihood of other ligamentous involvement, the Anterior and Posterior Drawer Tests as well as Patellar dislocation special tests should be performed.[1] Classification of Injury:[1] LCL injuries are classified in to three grades depending on severity. Grade I: Mild Sprain
Grade II: Partial Tear
Grade III: Complete Tear
Grade 1 and 2: Acutely, a grade 1 and 2 LCL injury can be treated with rest, ice, compression and NSAIDs [1]. Conservative management of LCL injuries is most commonly followed in grade I or II sprains[5]. Patients should be non-weightbearing for the first week and continue in a hinged-brace for the following 3 to 6 weeks while performing functional rehabilitation in order to maintain medial and lateral stability.[1] Grade 3: Acutely, a grade 3 LCL injury should also be treated with rest, ice, compression and NSAIDs [1]. Grade III sprains are more severe with the possibility of the anterior cruciate, posterior cruciate ligaments or posterolateral corner also being damaged. In this case, surgery is needed to prevent further instability of the knee joint.[6] Recent literature shows that reconstruction surgery is the best treatment option for grade 3 LCL injuries with a goal of achieving a stable, well-aligned knee with normal biomechanics [1][7]. Surgical management of isolated LCL injuries involves reconstruction of the LCL using a semitendinosus autograft [1].
For general management see: Ligament injury management As with other ligament injuries such as ACL repairs or ruptures a milestone-based approach can be undertaken, however, normal soft tissue healing timescales should be kept in mind when designing rehab programs[5]. Acute Management [5]
Sub-Acute Management Long-Term Management
An injury to the lateral collateral ligament of the knee can be caused by a varus stress or hyperextension to the knee joint. Additional damage to the ACL, PCL, posterio-lateral corner and lateral knee structures is possible with an LCL injury. In case of a grade III sprain, reconstructive surgery may be needed to prevent further instability of the knee joint. Conservative management should always be the initial treatment choice. What ligament would be damaged by a lateral force to the knee?A lateral collateral ligament (LCL) injury is usually caused by pressure or an injury that pushes the knee joint from the inside, which results in stress on the outside part of the joint. The symptoms of a tear in the lateral collateral ligament can include: Knee swelling.
Which ligament on the lateral side is most often injured?Your LCL (lateral collateral ligament) is a vital band of tissue on the outside of your knee. Athletes are more likely to tear it, causing a lot of pain and other symptoms. LCL tears usually heal after three to 12 weeks, depending on severity.
What is the most common knee ligament injury?The ACL is one of the most common ligaments to be injured. The ACL is often stretched or torn during a sudden twisting motion. This is when the feet stay planted one way, but the knees turn the other way. Slowing down while running or landing from a jump incorrectly can cause ACL injuries.
What is the most common injury to the lateral and medial collateral ligaments?Injuries to the medial collateral ligament most often happen when the knee is hit directly on its outer side. This stretches the ligaments on the inside of the knee too far or can tear them.
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