When you injure your knee, you may hear your doctor mention terms like Posterolateral Corner (PLC) injury or Medial Collateral Ligament (MCL) injury. These structures are critical for the stability of your knee — they help keep it steady, aligned, and able to handle twisting or side-to-side forces.
Understanding what these injuries mean and how they’re treated — especially if surgery like Open Posterolateral Corner Reconstruction or MCL Repair/Reconstruction is recommended — can help you feel more confident and prepared on your path to recovery.
General Points
What Are Posterolateral Corner and MCL Injuries?
The Posterolateral Corner (PLC) is a group of ligaments and tendons located on the outer back side of your knee. It helps control rotation and prevents the knee from buckling outward.
The Medial Collateral Ligament (MCL) sits on the inner side of your knee and stabilizes it against inward (valgus) forces.
Injuries to these areas often occur during sports, falls, car accidents, or sudden twisting motions. Because both the PLC and MCL work together to stabilize the knee, damage to one often affects the other. Untreated, these injuries can lead to chronic instability, pain, and early arthritis.
Common Symptoms
Patients with a Posterolateral Corner injury or MCL injury typically notice some combination of the following:
- Pain and swelling on the inside or outside of the knee
- Instability or “giving way”, especially when turning or walking downhill
- Difficulty fully straightening or bending the knee
- Tenderness over the outer (PLC) or inner (MCL) side of the joint
- Bruising that develops soon after the injury
In more severe cases, you might feel as though your knee just doesn’t “trust” you — it may feel unstable even during normal daily activities.
How These Injuries Are Diagnosed
An accurate diagnosis is key to successful treatment. Your orthopedic specialist will begin with a detailed history and physical examination, gently testing the stability of your knee using specific maneuvers.
Physical Exam
- Varus stress test (to assess the PLC)
- Valgus stress test (to assess the MCL)
- Dial test and posterolateral drawer test (to evaluate rotational stability)
Imaging Studies
- MRI (Magnetic Resonance Imaging) is the gold standard for confirming soft tissue injuries. It shows the extent of ligament damage and whether other structures, such as the ACL or meniscus, are also affected.
- X-rays may be taken to rule out associated fractures or subtle bone alignment changes.
This comprehensive evaluation helps your orthopedic surgeon decide whether non-surgical care or surgical reconstruction will provide the best outcome.
Treatment Options for Posterolateral Corner and MCL Injuries
Treatment depends on the severity of the injury, how many structures are involved, and how stable the knee feels.
Non-Surgical Treatment
For mild or partial tears, your surgeon may recommend:
- Bracing to protect the knee and limit movement during healing
- Physical therapy to strengthen surrounding muscles and restore motion
- Activity modification to prevent further injury.
These approaches can work well for minor injuries. However, when the knee remains unstable — especially with combined PLC and MCL injuries — surgical reconstruction is often necessary to restore full function.
Surgical Treatment: Open Posterolateral Corner Reconstruction and MCL Repair/Reconstruction
When ligaments are completely torn or the knee remains unstable despite conservative care, surgery provides the best chance for a full recovery. The most reliable approach is Open Posterolateral Corner Reconstruction combined with MCL Repair or Reconstruction.
What Is Open Posterolateral Corner Reconstruction?
In this procedure, the surgeon rebuilds the damaged ligaments of the posterolateral corner using tendon grafts (either from your own tissue or a donor). These grafts are placed in precise anatomical positions to restore the natural stability and alignment of your knee.
The goal is to recreate the normal biomechanics of the joint — allowing it to move smoothly while resisting unwanted rotation and sideways forces.
What About MCL Repair or Reconstruction?
If your MCL is also torn, your surgeon may perform either:
- MCL repair, when the ligament is torn but still attached and can be sutured back into place; or
- MCL reconstruction, when the ligament is too damaged and must be replaced with a tendon graft.
Both procedures are often performed together in the same operation to fully restore stability.
Benefits of Surgical Reconstruction
Choosing Open Posterolateral Corner Reconstruction and MCL Repair/Reconstruction offers several key benefits:
- Restores knee stability so you can walk, run, and turn without fear of giving way
- Prevents future cartilage wear and early arthritis
- Improves strength and confidence in your knee for daily activities and sports
- Provides long-term relief from pain and instability
Recent studies show that modern reconstruction techniques have excellent success rates, with most patients returning to normal activities or sports within 6–9 months after surgery.
Why Choosing an Experienced Orthopedic Specialist Matters
Knee ligament reconstructions, particularly Posterolateral Corner and MCL injuries, require a deep understanding of knee biomechanics and precise surgical technique.
An experienced orthopedic specialist ensures that:
- All damaged structures are correctly identified and repaired.
- The reconstruction is anatomically accurate.
- Your rehabilitation plan is personalized for optimal healing and return to activity.
With expert care, most patients achieve excellent long-term outcomes and return to active, pain-free lifestyles.
Take the Next Step Toward Recovery
If you’ve been diagnosed with a Posterolateral Corner injury or MCL injury, don’t wait to get the expert guidance you need. Early, accurate treatment can prevent long-term instability and arthritis.
At our clinic, we specialize in Open Posterolateral Corner Reconstruction and MCL Repair/Reconstruction, helping patients regain confidence, strength, and mobility in their knees.
Schedule a consultation today with our orthopedic specialist to discuss your personalized treatment plan — and take the first step toward a stable, pain-free future.
