Autologous Chondrocyte Implantation (ACI)/DeNovo NT Implantation (Femoral Condyle)

Phase I (Weeks 0-12)

1. Weightbearing
   • Weeks 0–2: Non-weightbearing
   • Weeks 2–4: Partial weightbearing (30–40 lbs)
   • Weeks 4–6: Continue partial weightbearing; progress to one crutch at weeks 6–8
   • Weeks 6–12: Progress to full weightbearing with discontinuation of crutch use
2. Bracing
   • Weeks 0–2: Hinged knee brace locked in extension – remove for CPM and rehab with PT
   • Weeks 2–4: Gradually open brace at 20° intervals as quad control is obtained
   • Discontinue brace when patient can perform straight leg raise without an extension lag
3. Range of Motion
   • Continuous Passive Motion (CPM) machine for 6–8 hours per day for 6 weeks
   • Set CPM to 1 cycle per minute – initially 0–30°
   • Increase flexion 5–10° per day until full flexion is achieved
   • Target: 90° by week 4 and 120° by week 6
   • PROM / AAROM and stretching under guidance of PT
4. Therapeutic Exercises
   • Weeks 0–2: Straight leg raises, quad sets, hamstring isometrics
   • Perform exercises in brace if quad control is inadequate
   • Weeks 2–6: Begin progressive isometric closed-chain exercises**
   • Week 6: Begin weight-shifting activities with operative leg in extension
   • Weeks 6–10: Progress bilateral closed-chain strengthening; begin open-chain knee strengthening
   • Weeks 10–12: Begin resisted closed-chain exercises (< body weight); progress to unilateral closed-chain exercises
   • Week 10: Begin balance exercises and stationary bike with light resistance

Phase II (Weeks 12-24)

1. Weightbearing: Full weightbearing with normal gait pattern
2. Range of Motion – Advance to full / painless ROM
3. Therapeutic Exercises
   • Advance bilateral and unilateral closed-chain exercises
   • Emphasis on concentric and eccentric control
   • Stationary bike, treadmill, Stairmaster, elliptical
   • Progress balance and proprioception exercises
   • Start sport-cord lateral drills

Phase III (Months 6-9)

1. Weightbearing: Full weightbearing with normal gait pattern
2. Range of Motion – Advance to full / painless ROM
3. Therapeutic Exercises
   • Advance strength training
   • Start light plyometric exercises
   • Start jogging and sport-specific training at 6 months

Phase IV (Months 9-18)

1. Weightbearing: Full weightbearing with normal gait pattern
2. Range of Motion – Full / painless ROM
3. Return to impact athletics at 16 months if pain free
4. Maintenance program for strength and endurance
5. Therapeutic Exercises
   • Continue closed-chain strengthening and proprioception activities
   • Emphasize single-leg loading
   • Sport-specific rehabilitation – running and agility training at 9 months

Comments

• Weeks 2–6 – Respect the repair site: if anterior lesion, avoid loading in full extension; if posterior lesion, avoid loading in flexion >45°