title: Fresh-frozen Complete Extensor Mechanism Allograft versus Autograft Reconstruction in Rabbits.
abstract: Different clinical results have been reported in the repair of extensor mechanism disruption using fresh-frozen complete extensor mechanism (CEM) allograft, creating a need for a better understanding of fresh-frozen CME allograft reconstruction. Here, we perform histological and biomechanical analyses of fresh-frozen CEM allograft or autograft reconstruction in an in vivo rabbit model. Our histological results show complete incorporation of the quadriceps tendon into the host tissues, patellar survival and total integration of the allograft tibia, with relatively fewer osteocytes, into the host tibia. Vascularity and cellularity are reduced and delayed in the allograft but exhibit similar distributions to those in the autograft. The infrapatellar fat pad provides the main blood supply, and the lowest cellularity is observed in the patellar tendon close to the tibia in both the allograft and autograft. The biomechanical properties of the junction of quadriceps tendon and host tissues and those of the allograft patellar tendon are completely and considerably restored, respectively. Therefore, fresh-frozen CEM allograft reconstruction is viable, but the distal patellar tendon and the tibial block may be the weak links of the reconstruction. These findings provide new insight into the use of allograft in repairing disruption of the extensor mechanism.
authors.affiliation: Department of Orthopedics, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an 710038, China.
authors.forename: Guanyin
authors.initials: G
authors.lastname: Chen
authors.affiliation: Department of Orthopedics, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an 710038, China.
authors.forename: Hongtao
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Orthopedics, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an 710038, China.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Ma
authors.affiliation: Department of Orthopedics, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an 710038, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Department of Orthopedics, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an 710038, China.
authors.forename: Yinglong
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Orthopedics, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an 710038, China.
authors.forename: Qingyu
authors.initials: Q
authors.lastname: Fan
authors.affiliation: Department of Orthopedics, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an 710038, China.
authors.forename: Baoan
authors.initials: B
authors.lastname: Ma
mesh_terms: D064591:Allografts / Q000098:blood supply / Q000473:pathology; D000818:Animals; D064592:Autografts / Q000098:blood supply / Q000473:pathology; D001696:Biomechanical Phenomena; D050376:Bone-Patellar Tendon-Bone Grafting; D005615:Freezing; D023421:Models, Animal; D010011:Osteocytes / Q000502:physiology*; D052097:Quadriceps Muscle / Q000601:surgery; D011817:Rabbits; D001405:Reflex, Babinski; D013977:Tibia / Q000601:surgery