MCL, LCL and PCL Injuries: Symptoms, Causes and Treatment
The knee is held together by strong bands of tissue called ligaments, and an injury to any of them can cause pain and make the knee feel unstable. The MCL, the ligament on the inner side of the knee, is commonly injured, but the LCL on the outer side and the PCL deep inside the joint can be hurt as well. These injuries are common in sports and active life, and many of them, especially MCL injuries, can be treated without surgery.
If you have hurt your knee and it feels painful or unstable, the right diagnosis points you to the right treatment. The board-certified and fellowship-trained knee and sports medicine specialists at Resurgens Orthopaedics diagnose and treat knee ligament injuries at locations across metro Atlanta.
Overview
- The Knee Ligaments
- MCL Tear
- LCL Injury
- PCL Injury
- How Knee Ligament Injuries Are Diagnosed
- Knee Ligament Injury Treatment
- Schedule an Appointment for a Knee Injury
The Knee Ligaments
Four main ligaments connect the thighbone to the bones of the lower leg and keep the knee stable. Two are collateral ligaments, found on the sides of the knee, and two are cruciate ligaments, which cross in the center. The medial collateral ligament, or MCL, runs along the inner side of the knee. The lateral collateral ligament, or LCL, runs along the outer side. The posterior cruciate ligament, or PCL, sits deep in the back of the joint and works alongside the better-known anterior cruciate ligament. Each can be stretched or torn, and injuries are graded from a mild stretch to a partial tear to a complete tear.
MCL Tear
An MCL tear is one of the most common knee injuries. It usually happens when a force pushes the knee inward, such as a blow to the outer side of the knee or a sudden twist or cut with the foot planted. This is common in contact and pivoting sports like football, soccer, skiing and basketball. Symptoms of an MCL tear include:
- Inner Knee Pain: Pain and tenderness along the inner side of the knee
- Swelling: Swelling around the knee
- Popping: A pop felt or heard along the inner side of the knee at the moment of impact
- Instability: A feeling that the knee is loose or might give way
- Stiffness: Difficulty fully bending or straightening the knee
The MCL has a blood supply that supports healing, and most isolated MCL tears respond well to nonsurgical treatment with structured rehabilitation. The MCL is also commonly injured together with the ACL, which can change the treatment plan.
LCL Injury
The lateral collateral ligament stabilizes the outer side of the knee. An LCL injury is less common than an MCL injury and usually results from a blow to the inner side of the knee that forces it outward, or from a hyperextension or twisting injury. Symptoms are like an MCL injury but felt on the outer side of the knee, with pain, swelling and a sense of instability. The LCL is part of a group of stabilizing structures on the outer knee, and unlike MCL tears, LCL tears do not heal on their own, so surgery is the standard for most complete LCL tears, especially when other ligaments are involved.
PCL Injury
The posterior cruciate ligament keeps the shinbone from sliding too far backward. A PCL injury most often comes from a direct blow to the front of a bent knee, such as falling onto a bent knee, and it can also happen in sports. PCL injuries can be subtle, and symptoms include pain, swelling and a feeling of instability, though some people have surprisingly mild symptoms at first. Many isolated PCL injuries are managed without surgery, while surgery is considered for severe injuries or when more than one ligament is torn.
How Knee Ligament Injuries Are Diagnosed
A knee specialist can usually identify which ligament is injured with a physical examination and your account of how the injury happened. Your physician will check for swelling and tenderness and gently stress the knee from different directions, comparing it to your other knee to feel for looseness in a specific ligament. An X-ray can rule out a fracture, including an avulsion injury where the ligament pulls away a small piece of bone, and an MRI shows the ligaments in detail, confirms the injury and reveals whether more than one structure is involved, which is common in knee injuries.
Knee Ligament Injury Treatment
Treatment depends on which ligament is torn, how severe the injury is and whether more than one structure is involved. Many isolated MCL and PCL injuries are treated without surgery.
Nonsurgical Treatment
Conservative care is the starting point for many collateral ligament injuries:
- Rest, Ice and Elevation: Steps to bring down swelling in the early days
- Bracing: A brace to protect and stabilize the knee while it heals
- Crutches: Support at first to limit weight on the knee when needed
- Physical Therapy: Exercises to restore motion, then rebuild strength and stability
Surgical Treatment
Surgery is reserved for the more serious injuries, such as a complete LCL tear, a severe PCL injury or a torn ligament that comes with other knee damage, like a combined ACL injury. Depending on the situation, the surgeon may repair the existing ligament or reconstruct it using a tissue graft, usually through a minimally invasive approach. Your Resurgens surgeon will explain whether surgery is needed and what recovery would involve.
Please Note: A knee injury can involve more than one ligament, and a serious injury can affect the nerves or blood vessels around the knee. If your knee is badly swollen, unstable or you cannot bear weight after an injury, have it evaluated promptly so the full extent of the injury is not missed.
Schedule an Appointment for a Knee Injury
If you have injured your knee, a specialist can find out which ligament is involved and guide your recovery. Book an appointment online today with Resurgens Orthopaedics or call us at (404) 847-9999.