PRIMARY BONE TUMORS OF THE SACROILIAC JOINT

Abstract

Purpose of the study: Primary bone tumors of the sacroiliac joint are difficult to diagnose. We present the procedure used to resect these tumors and reconstruct the pelvic ring, and the carcinological and functional outcome.

Materials and Methods: This was a retrospective analysis of a consecutive series of patients treated for a tumor of the iliac bone or of the sacrum which involved the sacroiliac joint. Tumor grading was based on the Enneking classification and the functional outcome on the MSTS score.

Results: From 1986 to 2003, 24 patients were treated for a a tumor involving the sacroiliac joint. Six with invasion of the sacral body. The histology was osteosarcoma (n=8), chondrosarcoma (n=8), malignant hystiocytofibroma (n=3), Ewing’s sarcoma (n=2), schwannoma (n=1), leiomysarcoma (n=1) and haemangiopericytoma (n=1). Seventeen patients were given neoadjuvant chemotherapy. A wide crest approach was used to access both aspects of the pelvic ring. Neurological sacrifice was required in six patients. Operative time was 5.27 hours on average. Reconstruction was achieved with an autograft and instrumentation. The resection was wide in 11 cases, marginal in 12, and contaminated in one. The mean follow-up was 4.77 years. Ten patients died from their disease. Survival was correlated with the quality of the resection and with the initial tumor stage. Hemisacrectomy did not affect survival. Bone healing was achieved in 13 patient, ten who survived. The mean MSTS score was 48% at last follow-up in 14 survivors. For the nine patients who did not require neurological sacrifice, the mean score was 58%. For the five other patients, the mean score was 38% This score was 65% in patients with bone healing and 8% in those with nonunion.

Discussion: The survival of patients with a tumor of the sacroiliac joint is basically related to the histological diagnosis and the quality of the resection. If the disease can be controlled, the method of the reconstruction proposed here enables bone healing with a satisfactory functional result when neurological sacrifice can be avoided.