Clinically Significant Outcomes Following the Treatment of Focal Cartilage Defects of the Knee With Microfracture Augmentation Using Cartilage Allograft Extracellular Matrix: A Multicenter Prospective Study

Arthroscopy. 2021 May;37(5):1512-1521. doi: 10.1016/j.arthro.2021.01.043. Epub 2021 Feb 1.


Purpose: To determine the short-term outcomes following microfracture augmented with cartilage allograft extracellular matrix for the treatment of symptomatic focal cartilage defects of the adult knee.

Methods: Forty-eight patients enrolled by 8 surgeons from 8 separate institutions were included in this study. Patients underwent microfracture augmented by cartilage allograft extracellular matrix (BioCartilage; Arthrex, Naples, FL) and were followed at designated time points (3, 6, 12, and 24 months) to assess patient-reported outcomes (PROs), clinically significant outcomes (CSOs), and failure and complication rates. Magnetic resonance imaging (MRI) was offered at 2 years postoperatively regardless of symptomatology, and Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) 2.0 score was documented.

Results: PRO compliance was 81.3% at 6 months, 72.9% at 12 months, and 47.9% at 2 years. All joint-specific and function-related PROs significantly improved compared to baseline at 3, 6, 12, 18, and 24 months of follow-up (P < .01), apart from Marx activity scale, which demonstrated a significant decline in postoperative scores at 2 years (P = .034). The percentage of patients achieving CSOs (as defined for microfracture) at 2 years was 90% for minimal clinically important difference and 85% for patient acceptable symptomatic state. Patient factors including age, sex, body mass index, symptoms duration, smoking, presence of a meniscal tear, lesion size, and location were not associated with CSO achievement at 2 years. One patient (2.1%) failed treatment 9.5 months postoperatively due to graft delamination and required a reoperation consisting of arthroscopic debridement. One complication (2.1%) consisting of complaints of clicking, grinding, and crepitus 15 months following the index procedure was reported. Two-year postoperative MRI demonstrated a mean 40.5 ± 22.9 MOCART 2.0 score.

Conclusions: In this preliminary study, we found cartilage allograft extracellular matrix to be associated with improvement in functional outcomes, high rates of CSO achievement, and low failure and complication rates at 2-year follow-up.

Level of evidence: Level III, prospective multicenter cohort study.

Publication types

  • Clinical Trial
  • Multicenter Study

MeSH terms

  • Adult
  • Allografts / transplantation*
  • Cartilage, Articular / surgery*
  • Cohort Studies
  • Extracellular Matrix / transplantation*
  • Female
  • Follow-Up Studies
  • Fractures, Stress / diagnostic imaging
  • Fractures, Stress / pathology*
  • Humans
  • Knee Joint / diagnostic imaging
  • Knee Joint / pathology*
  • Knee Joint / surgery*
  • Magnetic Resonance Imaging
  • Male
  • Patient Reported Outcome Measures
  • Postoperative Complications / etiology
  • Prospective Studies
  • Treatment Outcome