RT Journal Article
SR Electronic
T1 Repurposing Human Osteoarthritic Cartilage as a Bone Graft Substitute in an Athymic Rat Posterolateral Spinal Fusion Model
JF International Journal of Spine Surgery
JO Int J Spine Surg
FD International Society for the Advancement of Spine Surgery
SP 735
OP 742
DO 10.14444/5092
VO 12
IS 6
A1 ALAN B.C. DANG
A1 HELENA HONG
A1 KATIE LEE
A1 TAMMY LUAN
A1 SANJAY REDDY
A1 ALFRED C. KUO
YR 2018
UL http://ijssurgery.com//content/12/6/735.abstract
AB Background: Spinal fusion involves both endochondral and intramembranous bone formation. We previously demonstrated that endochondral cartilage grafts that were derived from human osteoarthritic (OA) articular cartilage can be used as a bone graft in mouse models. We hypothesized that OA cartilage could also be recycled and repurposed as a bone graft substitute in a posterolateral lumbar spinal fusion model in athymic rats. Methods: OA articular cartilage was obtained from the femoral resection of a healthy 60-year-old man undergoing elective total knee arthroplasty. The chondrocytes recovered from this tissue were dedifferentiated in monolayer tissue culture and then transitioned to culture conditions that promote chondrocyte hypertrophy. The resultant cell pellets were then used as bone graft substitute for single-level posterolateral spinal fusion in 5 athymic rats. Decortication alone was used as the control group. Spinal fusion was assessed with manual palpation, micro–computed tomography, and histologic analysis.Results: In the experimental group, micro–computed tomography at 4 and 8 weeks demonstrated bilateral fusion in 4 of 5 animals and unilateral fusion in 1 animal. At 8 weeks, manual palpation and histologic analysis showed direct correlation with the radiographic findings. Animals undergoing decortication alone failed to generate any spinal fusion. The difference in the fusion rate between groups was statistically significant with respect to both unilateral fusion (P = .047) and bilateral fusion (P = .007).Conclusions: In the absence of additional surgically implanted bone graft, hypertrophic chondrocyte grafts are sufficient for generating single-level posterolateral lumbar fusion in athymic rats.Clinical Relevance: This animal study demonstrates that cartilage harvested from OA knees can be used as a bone graft substitute. Commercially available cell-based bone grafts have previously only used mesenchymal stem cells or osteoblast precursor cells.