Medial collateral ligament (MCL) injury

A medial collateral ligament (MCL) injury happens when the ligament on the inside of the knee is stretched, partially torn, or completely torn. This common knee injury often occurs during sports or accidents when the knee is pushed inward by pressure or stress on the outside part of the knee. An MCL injury frequently takes place at the same time as an anterior cruciate ligament (ACL) injury.  

The Penn Orthopaedics team offers advanced nonsurgical and surgical treatments to effectively manage all types of knee injuries, including MCL injuries.

If you have an MCL injury, you may notice these common symptoms: 

• Pain and tenderness on the inner side of the knee 
• Swelling around the knee joint 
• A feeling of instability in the knee when weight is applied 
• Stiffness that makes it hard to move the knee 

MCL injuries are often caused by a direct blow to the outside of the knee, which forces the ligament on the inside to stretch or tear. For example, a hit to the outside part of the knee during football is a common way for this ligament to be injured. Movements in sports that involve sudden changes in direction or twisting motions, especially when the foot remains planted, may cause MCL injuries. Repetitive stress on the knee over time can also weaken the ligament and increase the risk of injury.  

Follow these suggestions to help protect your knees and lower the risk of MCL injuries: 

• Warm up: Do dynamic stretches and light cardio exercises before your workout or sporting event. 
• Build strength: Strengthen your quadriceps, hamstrings, and calves to support your knees. 
• Stay flexible: Keep the muscles around your knees flexible. 
• Use proper form: Practice appropriate jumping, landing, and direction-changing techniques. 
• Wear the right shoes: Choose supportive, cushioned footwear for your sport. 
• Improve balance: Add balance and coordination exercises to boost knee stability. 
• Increase activity levels gradually: Avoid overtraining by slowly increasing workout intensity. 
• Rest well: Take breaks between workouts to let your body recover. 
• Consider knee braces: Use braces for extra support during high-risk activities, especially if you’ve had past injuries. 
• Strengthen your core: Develop your core muscles to improve overall control and help reduce knee strain. 

If you’ve damaged any of the ligaments in your knee, you need an experienced orthopaedist to help you restore stability and daily function. The Penn Orthopaedics team offers the latest nonsurgical and surgical treatments for all types of ligament conditions, including MCL injury. 

Our Sports Medicine program provides complete orthopaedic care for people of all ages and activity levels — not just athletes. With a focus on research and innovation, we create individualized treatment plans for common to complex cases.