The posterior cruciate ligament (PCL) is one of the four major knee ligaments. It's stronger than the ACL and injured less often, usually from a direct blow to the front of the shin (dashboard injuries, falls onto a flexed knee) or hyperflexion of the knee.
Grading
- Grade 1 — mild sprain, minimal instability
- Grade 2 — partial tear, moderate instability
- Grade 3 — complete tear, significant posterior instability of the knee
Why non-operative management is common
Unlike ACL injuries, most PCL sprains — including grade 3 — do well with structured rehab. The PCL has good healing potential when protected, and the surrounding musculature can compensate effectively for residual laxity. Surgical reconstruction is typically reserved for combined ligament injuries or highly unstable knees.
Early phase (weeks 0-2)
Protect the knee — brace as prescribed. Preserve mobility with pain-free range work.
- Quad sets — press the back of the knee down into a rolled towel, hold 10 seconds. 10 reps, 3x daily.
- Straight leg raise — with knee straight, lift the leg to hip height. 10 reps, 3x daily.
- Ankle pumps for circulation.
Intermediate phase (weeks 2-6)
- Wall slides — light knee flexion under control
- Terminal knee extension with a resistance band
- Stationary bike with low resistance
- Single-leg balance drills
- Glute bridges and clam shells for hip strength
Progressive strengthening (weeks 6-12)
- Bodyweight squats to a comfortable depth
- Step-ups and step-downs
- Lunges with proper knee control
- Heel raises for calf strength
- Progressive resistance for quads, hamstrings, and glutes
Return to sport (12+ weeks)
Depends on severity, sport demands, and recovery. Return criteria include full pain-free range, quad and hamstring strength symmetry, and sport-specific movement without symptoms.
Why the quad focus matters
Strong quadriceps compensate directly for PCL laxity by pulling the tibia forward (opposite to the direction the injured ligament would normally restrain). Quad-focused rehab dramatically reduces long-term functional deficits.
PCL sprains can be managed well non-operatively with structured care. If you're recovering from one, come in for a program tailored to your stage and goals.