Early loss of subchondral bone following microfracture is counteracted by bone marrow aspirate in a translational model of osteochondral repair

Liang Gao,Henning Madry,Kathrin Müller-Brandt,Magali Cucchiarini,Lars K H Goebel,Patrick Orth

doi:10.1038/srep45189

Abstract

Microfracture of cartilage defects may induce alterations of the subchondral bone in the mid- and long-term, yet very little is known about their onset. Possibly, these changes may be avoided by an enhanced microfracture technique with additional application of bone marrow aspirate. In this study, full-thickness chondral defects in the knee joints of minipigs were either treated with (1) debridement down to the subchondral bone plate alone, (2) debridement with microfracture, or (3) microfracture with additional application of bone marrow aspirate. At 4 weeks after microfracture, the loss of subchondral bone below the defects largely exceeded the original microfracture holes. Of note, a significant increase of osteoclast density was identified in defects treated with microfracture alone compared with debridement only. Both changes were significantly counteracted by the adjunct treatment with bone marrow. Debridement and microfracture without or with bone marrow were equivalent regarding the early cartilage repair. These data suggest that microfracture induced a substantial early resorption of the subchondral bone and also highlight the potential value of bone marrow aspirate as an adjunct to counteract these alterations. Clinical studies are warranted to further elucidate early events of osteochondral repair and the effect of enhanced microfracture techniques.

Highlights

Microfracture of cartilage defects may induce alterations of the subchondral bone in the mid- and longterm, yet very little is known about their onset
The key finding is that microfracture treatment of chondral defects induced a substantial early loss of the subchondral bone that may be significantly counteracted if bone marrow aspirate is applied
Debridement and microfracture without or with bone marrow aspirate were all equivalent regarding the early phase of articular cartilage repair

Summary

Introduction

Microfracture of cartilage defects may induce alterations of the subchondral bone in the mid- and longterm, yet very little is known about their onset These changes may be avoided by an enhanced microfracture technique with additional application of bone marrow aspirate. Enhanced techniques of microfracture have been described, aiming to better support chondrogenesis within the cartilage defect[3,4,5] Among those techniques, the application of bone marrow concentrate as an adjunct to the microfracture technique has been shown to improve articular cartilage repair in animal models[4,6] and patients[7,8]. We evaluated the early effects of debridement alone and microfracture treatment without or with bone marrow aspirate on cartilage and subchondral bone repair in a full-thickness chondral defect model in minipigs. We tested the hypothesis that additional application of bone marrow aspirate to the microfracture procedure would improve the status of the subchondral bone compared with microfracture alone

Methods

Results

Conclusion