Lateral Collateral Ligament Tear
Brent S. E. Rich
Mitchell Pratte
BasicsDescription
-
Partial or complete sprain of the lateral collateral ligament (LCL) owing to an acute force, usually from a medial direction
-
Consists of a cordlike fiber bundle that runs from the lateral femoral condyle to the lateral aspect of the fibular head about 1 cm anterior to the apex: discrete extracapsular structure.
-
Primary restraint to varus stress with the knee in extension
-
Isometric between 0 and 70 degrees of flexion, followed by slackening trend with deeper flexion
Epidemiology
-
Least commonly injured knee ligament; isolated injuries are rare.
-
Infrequent site of overuse injury or rupture
-
Wrestling is the most likely associated sport.
-
May be associated with injury to other ligaments [anterior cruciate ligament (ACL) or posterior cruciate ligament (PCL)] or structures of the posterolateral corner (popliteus tendon, biceps femoris, iliotibial band, popliteofibular ligament) and peroneal nerve injuries
Risk Factors
-
Unclear if previous LCL injuries predispose to recurrent injury
-
Varus knee, otherwise normal, does not seem to be predisposed to LCL injury.
-
PCL deficiency may increase risk of LCL injury.
DiagnosisHistory
-
Contact or noncontact varus stress to partially flexed knee in internal tibial rotation from direct force or, more rarely, distal indirect stress (eg, stepping into a hole) with fixed foot
-
Acute lateral knee pain
-
Many hear/feel an associated “pop.”
-
LCL is extraarticular; mild to moderate swelling is associated with isolated injury.
-
Mild disability with low-grade injury; difficult weight bearing with high-grade injury/associated injuries owing to pain and instability
-
Instability with high-grade or moderate injury
-
Check for possible peroneal nerve symptoms.
Physical Exam
-
Signs and symptoms:
-
Acute lateral knee pain associated with a mechanism of varus stress with knee in flexion of 25–30 degrees
-
Patient may feel or hear a “pop” at time of injury.
-
Swelling variable, effusion not common with low-grade injuries; associated ligamentous injuries may cause significant effusion.
-
Instability symptoms in high-grade injury or with associated underlying varus knee
-
Possible peroneal nerve symptoms
-
-
Physical examination:
-
Local swelling over ligament
-
Tender to palpation over ligament
-
Readily palpated in “figure-of-4 position”: Normally a pencil-like structure but less distinct with partial tears (grade II) or complete tears (grade III)
-
Varus stress testing: Grade I sprain, no increased laxity; grade II sprain, increase in laxity with semifirm endpoint at 25–30 degrees of flexion isolates the LCL; grade III sprain, increase in laxity with soft or no endpoint compared with the uninjured knee indicates injury.
-
Careful assessment of ACL (Lachman test) and PCL (posterior drawer test), posterolateral structures (external rotation recurvatum test, external rotation roll-out test at 90 and 30 degrees, posterolateral drawer sign), and pivot shift if possible. Grade I injuries may be confused with lateral meniscal tears.
-
Peroneal nerve sensory and motor function should be checked as well.
-
Diagnostic Tests & Interpretation
Imaging
-
Plain films to rule out occult fracture of tibial plateau, lateral femoral condyle, or fibular head on all patients
-
MRI to better assess integrity of LCL and associated knee structures (ACL, PCL, lateral meniscus, popliteus tendon, posterolateral corner)
P.355
Differential Diagnosis
-
Proximal fibula avulsion fracture
-
Biceps femoris strain
-
Iliotibial band strain
-
Popliteus strain/tear
-
Associated anterior or posterior cruciate injury
-
Lateral meniscus tear
-
Lateral compartment chondral/osteochondral injury
-
Tibial plateau fracture
-
Associated loose body
-
Peroneal nerve injury
Treatment-
Acute treatment
-
Analgesia:
-
Ice and compression in acute setting
-
NSAIDs until acute pain subsides
-
Narcotics appropriate for 24–72 hr for grade II or III injuries or combined ligamentous injuries
-
-
Immobilization:
-
Grade I injury: No immobilization needed, but hinged bracing limiting flexion to 45–60 degrees is beneficial.
-
Grade II or III: Limited short-term use of knee immobilizer (<1 wk) followed by hinged brace, progressing through to full ROM over 4–6 wks
-
Bracing continues for contact or collision sport for the remainder of that season.
-
Additional Treatment
Additional Therapies
-
May consider more prolonged immobilization and bracing in varus knee, which is thought to increase stress on the injured ligament. This is somewhat controversial.
-
Rehabilitation:
-
In the acute setting, start isometric quadriceps exercises and straight-leg lifts.
-
Electrical stimulation/biofeedback to VMO quads
-
Gentle hamstring and calf strengthening in protective ROM
-
ROM exercises with progression to full ROM over 4–8 wks to allow ligament to heal without too much stress
-
Stair stepper or similar for CV conditioning can be added, limiting knee flexion to 45–60 degrees when tolerated.
-
Stationary bike later in rehabilitation when able to flex knee to 115 degrees without pain or residual swelling afterwards
-
When gait is normal, begin jogging and enhanced resistance exercises.
-
Progress to half sprints, full sprints, and cutting maneuvers once ligament fully healed.
-
Surgery/Other Procedures
Surgery is considered for grade III/combined ligamentous injuries.
Ongoing CareFollow-Up Recommendations
-
Referral to orthopedic surgery for any fracture, associated ligament injury, complex meniscal tear, or grade III injury that is not amenable to the initial 2–4 wks of rehabilitation
-
Associated neurovascular injuries should be considered emergent, and appropriate surgical/radiographic consultations should be initiated and performed on the same day.
Additional Reading
Kozanek M, et al. Posterolateral structures of the knee in posterior cruciate ligament deficiency. Am J Sports Med. 2009;3.
Van de Velde S, et al. The effect of anterior cruciate ligament deficiency on the in vivo elongation of the medial collateral and lateral collateral ligament. Am J Sports Med. 2007;35.
Victor J, et al. How isometric are the medial patellofemoral, superficial medial collateral, and lateral collateral ligaments of the knee? Am J Sports Med. 2009;37.
Wheeless' Textbook of Orthopaedics, Duke University, 2009, http://www.wheelessonline.com/ortho/lateral/collateral/ligament
CodesICD9
844.0 Sprain of lateral collateral ligament of knee
Clinical Pearls
-
Average return to play for grade I injury is 1–2 wks; grade II, 4–6 wks. Return to play is greatly dependent on the type of activity.
-
Once healed, there are no data to suggest that the ligament is more predisposed to recurrent injury.