Hemicortical Resection and Inlay Allograft Reconstruction for Primary Bone Tumors A Retrospective Evaluation in the Netherlands and Review of the Literature

Background: Selected primary tumors of the long bones can be adequately treated with hemicortical resection, allowing for optimal function without compromising the oncological outcome. Allografts can be used to reconstruct the defect. As there is a lack of studies of larger populations with sufficient follow-up, little is known about the outcomes of these procedures. Methods: In this nationwide retrospective study, all patients treated with hemicortical resection and allograft reconstruction for a primary bone tumor from 1989 to 2012 were evaluated for (1) mechanical complications and infection, (2) oncological outcome, and (3) failure or allograft survival. The minimum duration of follow-up was twenty-four months. Results: The study included 111 patients with a median age of twenty-eight years (range, seven to seventy-three years). The predominant diagnoses were adamantinoma (n = 37; 33%) and parosteal osteosarcoma (n = 18; 16%). At the time of review, 104 patients (94%) were alive (median duration of follow-up, 6.7 years). Seven patients (6%) died, after a median of twenty-six months. Thirty-seven patients (33%) had non-oncological complications, with host bone fracture being the most common (n = 20, 18%); all healed uneventfully. Other complications included nonunion (n = 8; 7%), infection (n = 8; 7%), and allograft fracture (n = 3; 3%). Of ninety-seven patients with a malignant tumor, fifteen (15%) had residual or recurrent tumor and six (6%) had metastasis. The risk of complications and fractures increased with the extent of cortical resection. Conclusions: Survival of hemicortical allografts is excellent. Host bone fracture is the predominant complication; however, none of these fractures necessitated allograft removal in our series. The extent of resection is the most important risk factor for complications. Hemicortical resection is not recommended for high-grade lesions; however, it may be superior to segmental resection for treatment of carefully selected tumors, provided that it is possible to obtain adequate margins.