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PubMed · 7644625

Massive osteoarticular knee allografts: structural changes evaluated with CT.

K T Mattila·J T Heikkila·A J Aho·I K Manner·P B Dean
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Abstract

PURPOSE: To analyze the structural changes seen at computed tomography (CT), particularly the findings that precede insufficiency (fatigue) fractures in massive osteoarticular knee allografts. MATERIALS AND METHODS: The subchondral and cancellous bone of 12 allografts were retrospectively evaluated with repeat transaxial CT (mean follow-up, 53 months). RESULTS: Early cortical graft resorption was followed by slow thickening after 6 months. Formation of resorptive cysts increased the cortical irregularity, which leveled off after 2 years. Late remodeling was evident as a subcortical sclerotic rim, "neocortex." Initially, the cancellous graft bone showed higher attenuation than the host bone; this difference subsided gradually during the first 3 years. Four insufficiency fractures were detected after the 1st postoperative year. Poor remodeling preceded these fractures. CONCLUSION: CT effectively depicted the structural changes during allograft incorporation and was superior to plain radiography for the detection of insufficiency fractures. The use of CT for follow-up of massive osteoarticular knee allografts provides additional information concerning the readiness of the graft for weight bearing.

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AdolescentAdultBone CystsBone RemodelingBone ResorptionBone TransplantationCartilageFemaleFollow-Up StudiesFractures, StressHumansKnee JointMaleMiddle AgedOsteosclerosisRetrospective StudiesTime FactorsTomography, X-Ray ComputedTransplantation, HomologousWeight-BearingJournal Article

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K T Mattila, J T Heikkila, A J Aho, I K Manner, P B Dean. 1995. Massive osteoarticular knee allografts: structural changes evaluated with CT.. https://doi.org/10.1148/radiology.196.3.7644625

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