Temporal in Vivo Assessment of Fresh Osteochondral Allograft Transplants to the Distal Aspect of the Femur by dGEMRIC (Delayed Gadolinium-Enhanced MRI of Cartilage) and Zonal T2 Mapping MRI

Abstract

Functional MRI techniques can be applied to noninvasively assess the biochemical health of cartilage after osteochondral allograft transplantation. The MRI findings correlated with certain patient-reported outcomes in the early postoperative period. Relative glycosaminoglycan content and the collagen structure of allograft cartilage may undergo time-dependent degeneration. A patient's perception of clinical outcome and quality of life is likely multifactorial and is impacted by more than the health of the allograft cartilage.

Cartilage Regeneration in Osteoarthritic Patients by a Composite of Allogeneic Umbilical Cord Blood-Derived Mesenchymal Stem Cells and Hyaluronate Hydrogel: Results from a Clinical Trial for Safety and Proof-of-Concept with 7 Years of Extended Follow-Up

“…At the 3‐year MRI assessment for the quality of repaired tissue, the average relative ΔR1 was 1.44 among the five participants studied, which suggests that the repaired tissue is comparable to healthy native cartilage. Previous reports indicate that relative ΔR1 was 1.32 at 1 year post‐ACI for focal chondral defects in nine patients (average age, 21.2 years) , and 1.13 and 1.55 at 1 year and 2 years, respectively, for postosteochondral allograft transplantation in nine patients (average age, 43.2 years) . Although the hUCB‐MSCs‐HA composite was transplanted at sites of osteoarthritic cartilage defects in elderly patients in this study, the relative ΔR1 of this study was comparable with that after ACI or osteochondral allograft transplantation in younger patients with focal chondral defects , .…”

“…Previous reports indicate that relative ΔR1 was 1.32 at 1 year post‐ACI for focal chondral defects in nine patients (average age, 21.2 years) , and 1.13 and 1.55 at 1 year and 2 years, respectively, for postosteochondral allograft transplantation in nine patients (average age, 43.2 years) . Although the hUCB‐MSCs‐HA composite was transplanted at sites of osteoarthritic cartilage defects in elderly patients in this study, the relative ΔR1 of this study was comparable with that after ACI or osteochondral allograft transplantation in younger patients with focal chondral defects , . These results suggest that hUCB‐MSC–HA hydrogel composite transplantation may have a more favorable outcome than currently available cartilage repair methods.…”

Clinical Utility of Advanced Imaging of the Knee

“…17 T 2 mapping and dGEMRIC have been most frequently studied in this capacity to date. [18][19][20][21][22] The advanced imaging measurements correlate with both arthroscopic findings at the time of surgical treatment of knee conditions and with patient results after treatment, reflecting the potential importance of these measurements in both diagnosis and objective evaluation of treatment outcomes. The routine addition of T 2 mapping to clinical sequences can improve the sensitivity and specificity for detection of cartilage injuries in the knee, highlighting both the feasibility of this method and the potential added benefit of acquiring this sequence.…”

“…Measurements from multiple different quantitative MR sequences also correlate with clinical outcomes after cartilage repair surgery . T 2 mapping and dGEMRIC have been most frequently studied in this capacity to date . The advanced imaging measurements correlate with both arthroscopic findings at the time of surgical treatment of knee conditions and with patient results after treatment, reflecting the potential importance of these measurements in both diagnosis and objective evaluation of treatment outcomes.…”

MRI Mapping for Cartilage Repair Follow-up

“…In nine patients (average age, 43.2 years) postosteochondral allograft transplantation, relative ΔR1 index were 1.13 at the first year and 1.55 at the second year [38].…”