Size of cartilage defects and the need for repair: a systematic review

Background: Cartilage defects are treated with a wide array of non-operative and surgical procedures. Optimal choice of treatment depends on lesion depth and size. Objectives: To review and summarize current data on the management of cartilage injuries in joints as it relates to defect size. Data sources: MEDLINE, Cochrane Central Register of Controlled Trials & Cochrane Library, CINHAL. Study eligibility criteria, participants, and interventions: Inclusion: (1) Studies investigating patients who underwent cartilage repair of the shoulder, elbow, hip, knee, and ankle. (2) Studies reporting outcome measures and treated lesion size. Exclusion: (1) No mention of defect size. (2) Joints not mentioned above. (3) <12 months clinical follow-up. (4) Unavailable full English or full texts. Study appraisal and synthesis methods: Selection procedure and homogeneity of patient population and preoperative and postoperative care were examined. Attrition bias was scored based on the percentage follow-up of the primary outcome parameter. Level of evidence was determined according to the guidelines of the Oxford Center for Evidence-Based Medicine. Results: Small lesions sized 1.5 cm² are often either fixated or conservatively treated, lesions sized >1.5 cm² mostly addressed with cell-based therapies such as autologous cartilage implantation (ACI), or matrix associated cartilage implantation (MACI). Large lesions often are the domain of osteochondral autograft transfer system (OATS). Limitations: Prospective randomized controlled studies are not available for every joint and many studies represent case studies with limited implications for treatment decisions. Conclusions and implications of key findings: Evidence-based treatment selection based on cartilage defect size can be beneficial. Systematic review registration number: 276559.