Hurting the ligament on the outside of your knee
An orthopedic knee surgeon and a physical therapist on LCL tears
The lateral collateral ligament, or LCL, helps the outside of the knee resist sideways force. A crash can bend the knee in a direction it isn’t meant to go. Afterward you may have pain along the outer side, swelling or a feeling that the knee will give way. [1]
The LCL can tear by itself. A high force injury, though, may damage more than one of the knee’s stabilizers. If only the sore spot is treated, the real reason the whole knee is unstable can be missed. [1]
Get a full map of the injury
During the exam, your doctor checks how the knee opens under gentle stress. The exam also looks for damage to other ligaments, the meniscus, cartilage, bone or nerves. X rays can look for a break. An MRI can show the soft tissues when needed. Tell your doctor if your foot feels numb or weak, or if the knee seemed out of place at any point. [1]
Fit treatment to how stable the knee is
A stable partial tear may heal with a hinged brace and guided rehab. A full tear, a ligament pulled off the bone or several torn structures may need surgery. Ask if you can put weight on the leg and how long to wear the brace. Find out when you can bend the knee. A therapist can help you regain motion and strength without putting sideways strain on the healing ligament. [1]
Stop testing the knee
Get a prompt checkup for repeated buckling, growing swelling or new weakness in the foot. A cold or pale foot after a severe knee injury is an emergency. Don’t twist the knee or push it sideways to see whether it still feels loose. [1]
Questions about the tear and your brace
- Is my LCL torn partway or all the way?
- Which other parts of my knee were checked?
- What are my limits for the brace, walking and therapy?
Check the brace fit before you walk
Ask your care team to show you how the brace should fit when you walk. [1]
Sources and further reading
General information from knee surgery and physical therapy experts. A tear of the lateral collateral ligament can happen along with other knee damage. Choices about bracing, walking and surgery depend on the full pattern of injury.
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