6-Month Postoperative Magnetic Resonance Imaging Appearance of Osteochondral Allografts With Bone Marrow Aspirate Augmentation From Either the Proximal Tibia or Iliac Crest.

Overview

abstract

BACKGROUND: There has been increased interest in the biologic augmentation of osteochondral allografts (OCAs), specifically the use of autologous bone marrow, to decrease failure rates. The iliac crest is a common donor site, but its use is associated with increased pain separate from the primary surgical site and increased complexity in the operating room setup and draping. Local bone marrow aspirate (BMA) from the proximal tibia or femoral condyle addresses these limitations, but the quality of the aspirate may be lower. It has not been determined whether this difference in aspirate quality influences the postoperative imaging appearance of OCA grafts. PURPOSE: To determine whether bone marrow aspirate augmentation from the iliac crest versus the proximal tibia affected 6-month postoperative magnetic resonance imaging (MRI) appearance of OCA grafts. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Patients undergoing OCA transplantation for grade IV chondral defects of the distal femur from January 2018 to June 2021, with 6-month (±2 months) postoperative knee MRI, were included in the study. Patients without knee postoperative MRI, patients with multiple plugs on different surfaces of the knee, and patients with patellar OCA plugs were excluded. Osteochondral Allograft Magnetic Resonance Imaging Scoring System (OCAMRISS) scores were calculated and compared for patients undergoing OCA with either ipsilateral iliac crest BMA augmentation or ipsilateral proximal tibia BMA augmentation. RESULTS: Of 56 patients (62 knees) who met the inclusion criteria, 33 had tibial BMA augmentation and 29 had iliac crest BMA augmentation. The mean age was 34.9 ± 10.4 years, the median [IQR] body mass index was 25.5 kg/m² [23.6-28.3 kg/m²], and the mean time from surgery to MRI was 6.2 ± 0.9 months. Most lesions involved the medial femoral condyle (29 lesions, 47%). The mean OCAMRISS score was 6.9 ± 2.8. There were no differences in the proximal tibia and iliac crest BMA groups with respect to demographic factors, lesion location, or OCAMRISS score on 6-month postoperative MRI (P > .05 for all). CONCLUSION: BMA augmentation does not affect the 6-month postoperative MRI appearance of OCA grafts.