Paper #41 - ISHA Annual Scientific Meeting 2016

Long-Term Benefit of Arthroscopic Autologous Matrix-Induced Chondrogenesis Compared to Microfracture for Femoral Acetabular Impingement-Induced Chondral Lesions

Andrea Fontana, MD, San Fedele Intelvi, Como ITALY

COF Lanzo Hospital - Sezione Ortopedia 1, Ramponio Verna, COMO, ITALY

The FDA has not cleared the following pharmaceuticals and/or medical device for the use described in this presentation. The following pharmaceuticals and/or medical device are being discussed for an off-label use: Geistlich Pharma, ChondroGide

Summary: Cartilage defects are frequently present in patients with FAI. Several arthroscopic treatment options are available including MFx and AMIC. In the present study tha AMIC technique using a collagen type I/III bilayer matrix (Chondro-Gide®) is having advantages in maintaining clinical improvements over time with less complications when compared to MFx in FAI.

The aim of this study is a single-centre retrospective analysis of the efficacy of arthroscopic autologous matrix induced chondrogenesis (AMIC) compared to microfracture (MFx) for the treatment of acetabular cartilage defects in femoro acetabular impingement (FAI) at 7 years follow-up.

Materials and Methods:
50 patients (35 male, 15 female) were treated with arthroscopic MFx and 59 patients (27 male, 32 female) were treated with arthroscopic AMIC with the application of a collagen type I/III bilayer matrix (Chondro-Gide®). Patients were evaluated pre- and post-operatively by the modified Harris Hip Score (mHHS) al 6, 12 months and then yearly until final follow-up. Data are reported as mean±standard deviation. Mean patient age at surgery was 38±10 (range 19-54 years) for MFx and 39±9 (range 18-50 years) for AMIC. All patients presented grade III to IV chondral defects (ICRS classification) with a mean lesion size of 3.6±1.4 cm2 (range2-8 cm2) for MFx and 3.5±1.5 cm2 (range 2-8 cm2) for AMIC. 20 patients in the MFx an 24 patients in the AMIC group had a concomitant chondropaty of the femoral head treated with microfracture only.

Baseline mHHS was 48±5 for MFx and 44±6 for AMIC. Major improvement was observed and comparable in the first 6 and up to 12 months after surgery, MFx 86±9 and AMIC 83±8. In the AMIC group this result was maintained over time with a mHHS of 81±7 at 7 years, while outcome in the MFx group deteriorated to 75±10. This deterioration was even more prominent in patients with large (=4 cm2) lesions. The mean mHHS improvement at 7 years follow-up with respect to pre-operative level was 26±10 for MFx ad significantly higher with 37±7 for AMIC. 9 patients in the MFx group subsequently required total hip arthroplasty (THA) compared to none in the AMIC group.

MFx and AMIC both led to clinical short-term improvement in patients with acetabular cartilage defects in FAI. AMIC, however, gave significantly better results which were maintained at a mean of 7 years follow-up, particularly in patients with large (=4 cm2) lesions. The conversion rate to THA was higher in the MFx group, with 9 patients (18%) requiring THA subsequently, compared to none in the AMIC group.