Follow-Up Study Evaluating the Long Term Outcome of ChondroMimetic in the Treatment of Osteochondral Defects in the Knee

Agnes Berta,Saara Totterman,Grahame Busby,Matthew S Shive,Gábor Vásárhelyi,Andrew K Lynn,Alan Getgood,László Hangody,Jerome Hollenstein,Imre Kéki

doi:10.3390/app10165642

Abstract

Scaffolds are thought to be a key element needed for successful cartilage repair treatments, and this prospective extension study aimed to evaluate long-term structural and clinical outcomes following osteochondral defect treatment with a cell-free biphasic scaffold. Structural outcomes were assessed using quantitative 3-D magnetic resonance imaging (MRI) and morphological segmentation to determine the percentage of defect filling and repair cartilage T2 relaxation times, and clinical outcomes were determined with the modified Cincinnati Rating System, and the Knee Injury and Osteoarthritis Outcome Score (KOOS). Seventeen subjects with osteochondral defects in the knee were treated with ChondroMimetic scaffolds, from which 15 returned for long-term evaluation at a mean follow-up of 7.9 ± 0.3 years. The defects treated were trochlear donor sites for mosaicplasty in 13 subjects, and medial femoral condyle defects in 2 subjects. MRI analysis of scaffold-treated defects found a mean total defect filling of 95.2 ± 3.6%, and a tissue mean T2 relaxation time of 52.5 ± 4.8 ms, which was identical to the T2 of ipsilateral control cartilage (52.3 ± 9.2 ms). The overall modified Cincinnati Rating System score was statistically significant from baseline (p = 0.0065), and KOOS subscales were equivalent to other cartilage repair techniques. ChondroMimetic treatment resulted in a consistently high degree of osteochondral defect filling with durable, cartilage-like repair tissue at 7.9 years, potentially associated with clinical improvement.

Highlights

Articular cartilage damage continues to present a therapeutic challenge, and despite multiple and differing approaches ranging from bone marrow stimulation [1], autologous chondrocyte implantation (ACI) [2], and various grafting procedures incorporating allografts and autografts [3,4], none areAppl
The fundamental goal of any cartilage repair treatment should be to avoid the progression to secondary osteoarthritis [8,9], by achieving structural repair that is comparable to native hyaline cartilage, and thereby assuring long-term durability, joint function, and pain relief
The study population was balanced by gender, and subjects received from 1 to 5 ChondroMimetic scaffolds, per knee, to treat trochlear donor sites for mosaicplasty in 13 subjects, and medial femoral condyle defects in 2 subjects

Summary

Introduction

Articular cartilage damage continues to present a therapeutic challenge, and despite multiple and differing approaches ranging from bone marrow stimulation [1], autologous chondrocyte implantation (ACI) [2], and various grafting procedures incorporating allografts and autografts [3,4], none areAppl. Sci. 2020, 10, 5642 recognized as sufficient. Recent reviews demonstrate that clinical research has failed to substantiate the superiority of one technique or product, in large part because of heterogeneous patient demographics, the differing etiologies of defects, and the varying study designs and outcome measures [5,6,7]. The lack of longer term (5–10 years) clinical evidence in cartilage repair further limits evidence-based treatment algorithms. The fundamental goal of any cartilage repair treatment should be to avoid the progression to secondary osteoarthritis [8,9], by achieving structural repair that is comparable to native hyaline cartilage, and thereby assuring long-term durability, joint function, and pain relief

Methods

Results

Discussion

Conclusion