Arthroscopic Treatment of Osteochondral Lesions of the Ankle with Matrix–Associated Chondrocyte Implantation.

SLR - February 2011 - Phong H. Le

Reference:  Aurich, M., Bedi, H., Smith, H., Rolauffs, B., Muckley, T., Clayton, J., Blackney, M.  Arthroscopic Treatment of Osteochondral Lesions of the Ankle With Matrix – Associated Chondrocyte Implantation.  The American Journal of Sports Medicine 2010; 20(10), 1-9.

Scientific Literature Review

Reviewed by:  Phong H. Le, DPM
Residency Program:  Cambridge Health Alliance, Cambridge, MA


Podiatric Relevance: 
In the past, good clinical results have been obtained from open repair of osteochondral lesions (OCL) of the ankle via tibial or fibular osteotomies; however they required a second surgical site to harvest autograft.  Recent advances with tissue bioengineering and ankle arthroscopic techniques have led to successful repair via the use of arthroscopic chondrocyte grafting for OCL of the ankle.  As of date, only one article by Giannini et al. (2008) showed that ankle arthroscopy MACI (Matrix-Associated Chondrocyte Implantation) is a safe procedure with low morbidity and complication rates. 

Methods: 
19 ankles in 18 patients with a mean age of 29.2 years +/- 10.0 with OCL of the ankle and tibial plafond were surgically treated with MACI from February 2006 and May 2008 by a single orthopedic surgeon.  Pre- and post-operative MRI images were obtained for each patient.  The mean surface area of the OCL was 1.5 +/- 0.8 cm and a mean depth of 0.4 +/- 0.2 cm.  11 of the 19 cases underwent arthroscopic debridement, microfracture or drilling before application of the MACI.  Loose osteochondral fragments were removed and sent to a single lab with mean culture time of 35-42 days before being placed on a porcine collagen type I scaffold.  In the second surgical procedure, the superficial fibrous tissue was debrided and the MACI was implanted and sealed with fibrin glue.  Ankle ROM was then checked to confirm the stability of the implant.  Post-operatively, patients were kept NWB for 2 weeks; followed by PWB for 4 weeks.  Full weight bearing was allowed after  6 weeks and high-impact sports allowed at 3 months following progressive therapy.

Results: 
Clinical examination was performed by an independent orthopedic surgeon not involved with the surgery. The FFI pain score improved from 5.5 +/- 2.0 points before MACI to 2.8 +/- 2.2 points after MACI. The mean AOFAS Hindfoot score improved from 58.6 +/- 16.1 points before MACI to 80.4 +/- 14.1 points after MACI, which are comparable to the results from Giannini et al, from 57.2 to 86.8 points.  The AAOS scores increased to 83.5 +/- 13.2 points after MACI.  All scores were statistically significant with P < .001.  This study showed an overall AOFAS score of 64% with patients rating good-to-excellent results.  81% of the patients were able to return to their previous sports activities.  The MRI evaluation was performed by a single blinded senior musculoskeletal radiologist.  The overall MOCART score was 62.4 +/- 15.8 points.  There was complete filling of the defect in 8 cases, incomplete but > 50% filling in 8 cases and hypertrophy observed in 3 cases.

Conclusions: 
Ankle arthroscopic MACI is a safe surgical technique which offers low morbidity and complication rates in ankle osteochondral lesions.  This procedure eliminates the need for donor site morbidity.  Overall the study demonstrated that the majority of the patients were asymptomatic post-operatively, and a high percentage of the patients were able to return to their previous sports activities.