Cartilage Restoration — Autologous Chondrocyte Implantation (ACI) — Femoral Condyle

Massachusetts General Hospital · MGH Sports Medicine

Weight-Bearing

Touch-down WB (20-30%) in locked knee brace wks 0-4; WBAT with bilateral crutches in unlocked brace wks 5-6 (unless otherwise directed based on defect location); brace locked at 0 deg for WB first 2 wks; discharge brace at 6 wks if SLR without lag; progress to full WB with normal gait wks 6-9

Key Restrictions

CPM 6-8 hrs/day in 2-hour blocks, starting 0-40 deg and increasing 5-10 deg/day; flexion goals 90 deg wk 2, 105 wk 3, 115 wk 4, 120 by wk 6; no weight-bearing flexion >90 deg in Phase II; posterior condyle lesions: avoid exercises in flexion >45 deg until Phase III; Phase III: avoid knee flexion >90 deg, significant pain, or soreness >24 hrs

Timeline & Phases

6 phases: Phase I (0-6 wks, TDWB in locked brace, CPM, stationary bike from wk 2, pool walking at wk 4 if wound closed), Phase II (6-12 wks, full WB with normal gait, single-leg balance wk 8, lateral step-down wk 10, deep water running), Phase III (12-24 wks, leg press and lunges <90 deg, aqua jogging; progress on bilateral squat to 90 deg and single-leg squat to 60 deg), Phase IV (6-9 months, advanced strengthening, LSI >80%), Phase V (9-12 months, return to running program, early return to sport), Phase VI (12-18 months, unrestricted return to sport: strength index and hop testing >90%, KOOS-sports >90%, IKDC >93)

Notes

Two-stage ACI (arthroscopic cartilage harvest, then open implantation 3-5 wks later); femoral condyle lesions; timing for some exercises differs for anterior vs posterior grafts (e.g., closed chain at wk 8 anterior vs wk 12 posterior); revised 12/2022; see the trochlea/patella ACI protocol for patellofemoral lesions

Surgeon / Author

MGH Sports Medicine

Published

December 2022