Arthroscopic PCL reconstruction for PCL tear
Several ligaments stabilize the human knee: the ACL, the PCL, the MCL, the LCL and the posterolateral corner complex (PLC). Injuries to the PCL can occur in isolation or in combination with other ligament injuries, and combined injuries are usually caused by high-energy mechanisms resulting in a knee dislocation. These may be limb-threatening and require prompt evaluation in an emergency room, because injury to the blood vessel running behind the knee is a real risk.
Symptoms
These injuries cause knee instability, to a degree that depends on how many ligaments are involved.
Isolated PCL injuries cause knee pain and a sense of instability initially. This typically settles with time, and most patients cope with a PCL-deficient knee.
PLC and LCL injuries cause pain on the outboard aspect of the knee and an inability to perform cutting manoeuvres because of instability.
Combined PCL, LCL and PLC injuries cause both pain and instability.
Why it happens
These injuries occur through high-energy trauma — motor vehicle accidents or sporting injuries — and require prompt medical attention. The LCL and PLC sit outside the knee joint and have greater healing potential than the PCL, which is inside the joint. Early repair of the LCL and PLC is therefore advocated, to make use of the healing response that occurs in the first three weeks after injury. The PCL heals less robustly, so late reconstruction is advocated for it.
How it is diagnosed
Diagnosis begins with a detailed history and a thorough physical examination. X-rays are the most important initial study; for the knee these are specialised, usually weight-bearing views. An MRI may be added to look more closely at all the ligaments.
Treatment
Isolated PCL injuries are typically treated non-operatively with physical therapy and a brace.
PLC and LCL injuries require surgical repair within two weeks of injury. Where there are also PCL and ACL injuries, those are reconstructed after the PLC and LCL have healed, at 6 to 12 weeks. Repairing a ligament means suturing the torn edges together or tightening a stretched ligament; reconstructing one means using other tissue, such as hamstring tendon or donor tendon, to rebuild it. These are usually arthroscope-assisted procedures, with incision length varying by injury and anatomy. If the knee is grossly unstable, an external fixator is used to stabilize it.
Depending on the extent of injury and the magnitude of surgery, patients may stay in hospital one to two days, particularly for monitoring of the nerves and blood supply to the leg.
Recovery
You will be placed in a brace, and weight bearing may be protected with crutches for several weeks. Range of motion will be restricted until healing has taken place. Physical therapy starts within a week of surgery for swelling control, muscle activation and other measures to aid healing. Rehabilitation for this type of injury can last 6 to 12 months.
Common questions
What are the dangers of a knee dislocation?
Knee dislocations are serious injuries that can threaten the limb if there is a vascular injury. Prompt specialised medical care is essential.
Can my own tissue be used to reconstruct multiple torn ligaments?
It is recommended against using your own tissue where multiple ligaments are injured. Donor (allograft) tissue is used instead.
What are the risks of multi-ligament reconstruction?
Infection, bleeding, damage to nerves and blood vessels, blood clots in the legs (DVT), and clots that break off and travel to the lungs (pulmonary embolus). Knee stiffness and compartment syndrome are additional risks.
Knee video
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