Rehabilitation After MCL Injury and Repair in Total Knee Replacement
Immediate Postoperative Phase (0-2 Weeks)
- The British Journal of Sports Medicine recommends initiating immediate knee mobilization within the first week to improve range of motion and reduce pain without compromising stability 1, 2
- Isometric quadriceps exercises, including static quadriceps contractions and straight leg raises, can be safely prescribed during the first 2 postoperative weeks and confer advantages for faster recovery of knee range of motion at 1 month without compromising stability 1, 3
- Progress weight-bearing as tolerated within the first week, though this should be more conservative than isolated ACL reconstruction given the MCL repair 2
- The evidence supports early weight-bearing reduces patellofemoral pain without increasing laxity 1
- Apply cryotherapy immediately after surgery to reduce knee pain and swelling 2, 3
- Consider neuromuscular electrostimulation (NMES) for the initial 6-8 weeks to re-educate voluntary quadriceps contraction 2
Moderate Protection Phase (2-6 Weeks)
- Prioritize closed kinetic chain exercises (leg press, squats, step-ups) over open kinetic chain exercises to minimize stress on the MCL repair 2, 3
- Closed kinetic chain exercises should be emphasized in the first 6-8 weeks to protect the healing ligament 3
- Begin leg press at 3 weeks to improve subjective knee function and functional outcomes 1
- Open kinetic chain exercises (90-45°) may be cautiously added as early as 4 weeks, but should be introduced with extreme caution given the MCL repair 2, 3
- Avoid aggressive resistance with open kinetic chain exercises during this phase 1
Minimum Protection Phase (6-12 Weeks)
- Advance to both open and closed kinetic chain exercises with progressive resistance 1, 3
- Combine strength training with neuromuscular/motor control training to restore dynamic stability 4, 3
- Implement eccentric training components, which may result in greater strength gains and quadriceps muscle hypertrophy 1
- Progress from basic activities of daily living to more demanding functional tasks 4
Return to Function Phase (3-6 Months)
- Base progression on objective criteria rather than time alone 4, 3
- Achieve limb symmetry index >90% for strength testing before advancing to higher-level activities 3
- Ensure no pain, swelling, or instability on examination 4
- Perform isokinetic quadriceps and hamstring peak torque testing at 60°/s demonstrating 100% symmetry 4
- Assess countermovement jump and drop jump with >90% symmetry 4
- Evaluate patient-reported outcomes including IKDC subjective knee form and psychological readiness scales 4, 2
Critical Pitfalls to Avoid
- Early mobilization is critical to prevent stiffness, but must be balanced with ligament protection 1, 2
- Do not advance to aggressive open kinetic chain exercises before 4 weeks 2, 3
- Maintain a conservative approach to open kinetic chain exercises due to the presence of MCL repair 3
- Prioritize closed kinetic chain exercises in early phases to protect the healing ligament 2, 3
- Use criteria-based rather than time-based progression to higher-level activities 4, 3