LCL Tear
A lateral collateral ligament (LCL) injury involves damage to one of the key ligaments that stabilizes the outer (lateral) side of the knee. LCL injuries are less common than injuries to the ACL or MCL but can occur during sports, trauma, or accidents that place stress on the outside of the knee. Injury severity ranges from mild stretching to complete ligament rupture. Many LCL injuries can be treated without surgery, though more severe injuries or those associated with other ligament damage may require operative management.
LCL injuries typically occur when a force is applied to the inner side of the knee, causing the knee to bend outward (varus stress). Common mechanisms include:
- A direct blow to the inside of the knee
- Contact sports injuries (football, soccer, hockey)
- Sudden changes in direction or pivoting
- Falls or motor vehicle accidents
- Hyperextension injuries
LCL injuries often occur in combination with other knee ligament injuries, particularly to the posterior cruciate ligament (PCL) or structures of the posterolateral corner.
The LCL is a strong, cord-like ligament located on the outside of the knee. It connects:
- The femur (thigh bone) to
- The fibula (outer lower leg bone)
The LCL helps stabilize the knee against varus (outward bending) forces and contributes to overall knee stability, especially during cutting and pivoting activities. It is part of the posterolateral corner (PLC) of the knee, a complex group of structures that also includes tendons and other ligaments that provide rotational stability.
Symptoms depend on the severity of the injury and may include:
- Pain or tenderness on the outside of the knee
- Swelling (often less pronounced than with ACL injuries)
- Bruising along the outer knee
- A feeling of instability or the knee “giving way” – often caves outward
- Pain with walking, pivoting, or side-to-side movements
- Difficulty returning to sports or physical activity
Severe injuries may result in noticeable instability during walking where the moves outwardly
Evaluation of a suspected LCL injury begins with a thorough medical history and physical examination.
Medical history
- How the injury occurred (contact, twisting, fall, or trauma)
- When symptoms started
- Presence of instability or the knee “giving way”
- Ability to bear weight or return to activity
Physical examination
The knee is examined to assess:
- Tenderness along the outside of the knee
- Swelling or bruising
- Knee stability and alignment
- Specific stress tests that apply gentle outward force to the knee to evaluate LCL integrity
- Range of motion and strength
Because LCL injuries commonly occur with other ligament injuries, the entire knee is carefully evaluated.
Imaging
Imaging studies may be ordered to confirm the diagnosis or assess injury severity:
- X-rays to rule out fractures or bone avulsion injuries
- MRI to evaluate the LCL and identify associated injuries to the ACL, PCL, meniscus, or posterolateral corner structures
Accurate evaluation is important to guide treatment decisions and ensure that associated injuries are not missed.
Initial care focuses on protecting the knee and reducing pain and swelling:
- Rest: Avoid activities that worsen symptoms
- Ice: Apply ice for 15–20 minutes several times daily
- Compression: Use an elastic wrap or knee brace
- Elevation: Elevate the leg when possible
- Pain control: Anti-inflammatory medications if appropriate
- Bracing: A hinged knee brace may be recommended for support
Prompt medical evaluation is important to assess the extent of injury and rule out associated ligament damage.
Many isolated LCL injuries heal successfully without surgery.
Indications for nonoperative treatment include:
- Grade I (mild) and Grade II (partial) LCL injuries
- Stable knee on examination
- Isolated LCL injury without damage to other ligaments
Nonoperative management may include:
- Hinged knee bracing to protect against varus stress
- Activity modification and gradual return to weight-bearing
- Physical therapy focusing on:
- Restoring range of motion
- Strengthening the quadriceps and hamstrings
- Balance and neuromuscular training
- Gradual return to sport or activity
Surgery is less common but may be necessary in certain situations.
Indications for operative treatment include:
- Grade III (complete) LCL tears
- Persistent knee instability despite nonoperative treatment
- Combined ligament injuries (such as LCL with ACL or PCL injury)
- Significant posterolateral corner injuries
- Associated fractures or nerve injury
Surgical options may include:
- LCL repair in acute injuries
- Ligament reconstruction using donor tissue
- Repair or reconstruction of associated posterolateral corner structures
Nonoperative Outcomes:
- Most patients with mild to moderate injuries recover well
- Return to daily activities and sports is common with proper rehabilitation
- Recovery time typically ranges from weeks to a few months
- Inadequate rehabilitation may lead to chronic instability
Operative Outcomes:
- Good to excellent outcomes in appropriately selected patients
- Improved knee stability and function
- Longer recovery and rehabilitation period
- Low but present risks of complications such as stiffness, nerve irritation, or infection
LCL injuries are less common knee ligament injuries that can range from mild to severe. Early diagnosis and appropriate management are key to achieving a good outcome. Most isolated LCL injuries can be treated successfully without surgery, while severe or combined ligament injuries may require operative intervention. With proper treatment and rehabilitation, most patients can expect a return to normal function and activity.
At a Glance
Dr. Hasani Swindell
- Fellowship-Trained Sports Medicine Specialist
- Board-Certified Orthopedic Surgeon
- Summa Cum Laude Graduate from the University of Pittsburgh
- Medical Degree from Columbia University
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