Matrix-induced autologous chondrocyte implantation of talus articular defects

Osteochondral injury of the talus can be challenging to treat because the damaged articular cartilage has a poor intrinsic reparative capability. Autologous Chondrocyte Implantation has become an effective means for treating persistent cartilage lesions that fail to respond to routine ankle arthroscopy. The purpose of this study was to assess the results of Matrix-induced autologous chondrocyte implantation (MACI) for the treatment of osteochondral defects of the talar dome using a technique which does not require an osteotomy of the tibia or fibula.

A prospective investigation of MACI was performed on ten patients with full-thickness lesions of the talus. The patients had a documented talus lesion on MRI, failure of conservative treatment and arthroscopic debridement/curettage, persistent ankle pain and swelling, the absence of tibiotalar arthritis and a stable ankle. Five males and five females, with an average of 1.7 previous procedures prior to Matrix-induced autologous implantation, were included in this study. All patients were available for followup at 1 and 2 years. Lesions were graded during the harvesting procedure using the Cheng-Ferkel grading system, the Outerbridge classification, and the International Cartilage Repair Society system. Clinical and functional evaluation was done preoperatively, and at 1 and 2 years postoperatively using the AOFAS hindfoot evaluation and the SF-36 Health Survey.

Preoperative AOFAS hindfoot scores were 61.2 (range, 42 to 76) which improved 1 year postoperatively to 74.7 (range, 46 to 87) (p < 0.05) and 2 years postoperatively to 73.3 (range, 42 to 90) (p = 0.151). At both 1 and 2 years postoperatively, the results of the SF36 evaluation demonstrated a significant improvement in the Physical Functioning (p = 0.002) and Bodily Pain (p < 0.001) components. Subjectively, all ten patients believed this procedure helped them.

The results of this study suggest that MACI may be an effective way to treat full-thickness lesions of the talus using harvested chondrocytes from the talus without malleolar osteotomy. We recommend it for patients who do not respond to initial curettage and microfracture.