Fortunately, most often surgery is not necessary for the treatment of an MCL tear. In some specific circumstances, surgery may be recommended. Most often, surgery is used for treatment of the most severe MCL injuries.
Grade I MCL Tears:
Grade II MCL Tears:
Athletes with a grade II injury can return to activity once they are not having pain directly over the MCL or symptoms of instability. Patients with a grade II injury often return to sports within three or four weeks after their injury.
Grade III MCL Tears:
Once the patient can begin bending their knee, early range-of-motion exercises should commence, including stationary bicycling. Normal walking and progression to jogging can begin as pain allows. Use of a hinged knee brace is usually very helpful to support the knee, especially in the earlier stages of rehab. Most athletes return to sports about three months after a grade III MCL tear.
Surgery for MCL Tears:
Some surgeons advocate surgical treatment of grade III MCL tears in elite athletes or in those athletes with multiple ligament injuries in the knee. In these circumstances, you should discuss the optimal management of your injury with your doctor.
Miyamoto RG, et al. "Treatment of Medial Collateral Ligament Injuries" J. Am. Acad. Ortho. Surg., March 2009; 17: 152 - 161.