Mid-term (4-7 years) Results of Matrix-Associated Stem Cell Transplantation (MAST) in Chondral Defects of the First Metatarsophalangeal Joint

CATEGORY: Midfoot/Forefoot INTRODUCTION/PURPOSE: Matrix-associated stem cell transplantation (MAST) has shown good short-term results for treatment of chondral defects at first metatarsophalangeal joint (MTP1). The aim of the study was to assess mid-term results (=4-year-follow- up). METHODS: In a prospective consecutive non-controlled clinical follow-up study, 61 patients with 81 chondral defects at MTP1 that were treated with MAST from October 1, 2011 to October 31, 2014 were analysed. Degree of osteoarthritis, range of motion (ROM), size and location of the chondral defects, pedographic parameters, and the Visual Analogue Scale Foot and Ankle (VAS FA) before treatment and at follow-up were registered and analysed. Bone marrow aspirate was harvested from the ipsilateral pelvic bone marrow and centrifuged (10 minutes, 1,500 RPM). The supernatant was used to impregnate a collagen I/III matrix (Chondro-Guide). The matrix was fixed into the chondral defect with fibrin glue. RESULTS: Following mean (range) values were registered at time of surgery: age 44 (35-72) years, VAS FA 49.4 (12.3-82.3), ROM 20.4/0/8.4° (dorsiflexion/plantarflexion), degree of osteoarthritis 1.9 (1-3). The 81 chondral defects were located as follows, dorsal metatarsal head, n=28 (35%), plantar metatarsal head, n=12 (15%); dorsal & plantar, n=21 (26%); medial sesamoid, n=14 (17%); lateral sesamoid, n=6 (7%)(two defects, n=14, three defects, n=3). The defect size was 0.9 (.5 - 3.0) cm2. Fifty-six patients (92%) completed follow-up at 62 (48-84) months. VAS FA increased to 82.5 (45.6-100; t-test, p<.01). ROM increased to 30.2/0/15.4 (p=.05). Degree of osteoarthritis decreased to 1.1 (0-3, p=.04) CONCLUSION: The surgical treatment of chondral defects at MTP1 including MAST led to improved clinical scores, ROM and degree of osteoarthritis after 4-7 years. No adverse effects of MAST were registered. Even though a control group is missing, we conclude that MAST is an effective method for the treatment of chondral defects at MTP1.