Page 166 - Reconstructive Techniques in Musculoskeletal Tumor Surgery

Chapter 8
Abstract
Purpose: To assess risk factors for nonunion after intercalary allograft reconstruction, and to evaluate if cortical contact at the allograft-host junction results in a decreased likelihood of nonunion.
Methods: We retrospectively evaluated 96 osteotomies in 57 patients (34 males, 60%) with an intercalary allograft reconstruction of the femur or tibia for a primary bone tumor. Median follow-up was 8.6 years (95% CI 6.1-11.2). Only one-plane transverse osteotomies with plate xation were included. The degree of cortical contact was radiographically classi ed into grades 1 (full contact over the entire length of the osteotomy), 2A (≥50% contact), 2B (<50% contact), and 3 (lack of cortical contact).
Results: There were a total of 15 non-uniting osteotomies (15/96, 16%). Nonunion was the cause for revision surgery in none of the 23 (0%) grade 1, two of 29 (7%) grade 2A, ve of 28 (18%) grade 2B, and 8 of 16 (50%) grade 3 junctions. With grade 3 as the reference, the odds ratio for nonunion was 0.22 for grade 2B lesions (p=0.03) and 0.01 (p=0.003) for grade 2A lesions. Reconstruction site, patient age >16 years, localization within the bone or chemotherapy use did not signi cantly in uence nonunion risk.
Conclusion: Our results suggest that the degree of cortical contact at the allograft- host junction is the most important factor for the risk of developing nonunion. Care should be taken to obtain rigid xation with rm contact at the junction site.
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