Articular Cartilage Paste Grafting to Full-Thickness Articular Cartilage Knee Joint Lesions: A 2- to 12-Year Follow-up

Purpose: To prospectively assess clinical outcomes and regeneration of osteoarthritic cartilage lesions treated with an articular cartilage paste grafting technique. Type of Study: Prospective, longitudinal case series. Methods: We treated 125 patients (136 procedures; 34% female, 66% male; mean age, 46 years; range, 17 to 73 years) with an Outerbridge classification of grade IV lesions with an articular cartilage paste graft. Clinical data were recorded 2 to 12 years from surgery, with 20 of 145 patients lost to follow-up over 12 years (13.7%). Clinical outcomes were captured annually with validated Western Ontario and McMaster Universities Arthritis Index (WOMAC), International Knee Documentation Committee (IKDC), and Tegner subjective questionnaires. Regenerated cartilage biopsy specimens were obtained at second-look arthroscopy from 66 patients and evaluated as to quality and quantity of defect fill by a blinded, independent histopathology reviewer. Results: Preoperative versus postoperative validated pain, functioning, and activity measures improved significantly (P< .001). Clinically, 18 of the 125 patients were considered failures (14.4%), with 10 patients undergoing subsequent joint arthroplasty and 8 who reported worse pain after surgery. Regional histologic variation occurred. Forty-two of 66 biopsy specimens (63.6%) showed strong and consistent evidence of replacement of their articular surface, and 18 of 66 biopsy specimens (27.3%) showed development of areas of cartilage. Conclusions: Paste grafting is a low-cost, 1-stage arthroscopic treatment for patients with Outerbridge classification grade IV arthritic chondral lesions. The procedure offers excellent, long-lasting, pain relief, restored functioning, and possibility of tissue regeneration for patients with painful chondral lesions in both arthritic and traumatically injured knees. Level of Evidence: Level IV, case series.