Autologous Chondrocyte Implantation (ACI)/DeNovo NT Implantation (Trochlea/Patella)

Phase I (Weeks 0-12)

1. Weightbearing:- Weeks 0-2: Non-weightbearing.- Weeks 2-4: Partial weightbearing (30-40 lbs).- Weeks 4-8: Continue with partial weightbearing (progress to use of one crutch at weeks 6-8).- Weeks 8-12: 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: Locked in extension for weight bearing – Can open brace for NWB ROM 0-30°.
   - Weeks 4-6: Open brace to 30° for ambulation.
   - D/C brace at 6 weeks post-op.
3. Range of Motion – Continuous Passive Motion (CPM) Machine for 6-8 hours per day for 8 weeks. 
   - Set CPM to 1 cycle per minute – set at 0-30° for first 3 weeks.
   - Starting at week 3 increase flexion 5-10° per day until full flexion is achieved.
       - Should be at 90° by week 6 and 120° by week 8.
   - PROM/AAROM and stretching under guidance of PT.
4. Therapeutic Exercises: 
   - Weeks 0-4: Straight leg raise/Quad sets, Hamstring isometrics.
       - Perform exercises in the brace if quad control is inadequate.
   - Weeks 4-10: Begin isometric closed chain exercises.
       - At week 6 can start weight shifting activities with operative leg in extension.
   - At week 8 can begin balance exercises and stationary bike with light resistance.
   - Weeks 10-12: hamstring strengthening, theraband resistance exercises 0-30°, light open-chain knee isometrics.

Phase II (Weeks 12-24)

1. Weightbearing: Full weightbearing with a normal gait pattern.
2. Range of Motion – Advance to full/painless ROM.
3. Therapeutic Exercises:- Gait training/treadmill use at slow-moderate pace.- Progress balance/proprioception exercises.- Start sport cord lateral drills.

 Phase III (Months 6-9)

1. Weightbearing: Full weightbearing with a normal gait pattern.
2. Range of Motion – Advance to full/painless ROM.
3. Therapeutic Exercises:- Advance closed chain strengthening/Start unilateral closed chain exercises.- Progress to fast walking and backward walking on treadmill (add incline at 8 months). - Start light plyometric training.

Phase IV (Months 9-18)

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