Preliminary proposal: a classification system for reconstruction with autologous femoral head after periacetabular tumors resection.

Background: Although researchers have adopted various methods for the resection and reconstruction of periacetabular tumors, the total incidence rate of complications remains high. Aiming for preserving the acetabulum and reducing the risk of complications, we applied a surgery method using tumor-free autologous femoral head to reconstruct the defective acetabulum after resection of periacetabular tumors followed by performing a conventional total hip arthroplasty (THA). Moreover, we proposed a preliminary classification system for these surgery methods.

Methods: We retrospectively reviewed 6 patients treated with acetabulum reconstruction combined with autologous femoral head following peri-acetabulum resection between April 2010 and May 2018. All patients were diagnosed as periacetabular tumors including chondrosarcoma (n = 5) and chondroblastoma (n = 1). Clinical data such as age, diagnosis, complications, local recurrence or metastasis, and function (Musculoskeletal Tumor Society 1993, MSTS93) were documented. The average time of follow-up was 62.5 months (range, 17 to 106 months).

Results: A total of 5 patients survive with average MSTS93 score of 27.8 points (range, 26-30). One patient, suffering from multiple bone metastasis prior treatment, ended up dying. One who had received radiotherapy before surgery had poor incision healing. Further, a classification system was preliminary proposed in 2 patients involving the pubis (type A) and 4 patients involving ischium (type B).

Conclusions: Based on the results, we preliminary proposed a classification system for reconstruction with autologous femoral head after periacetabular low malignant tumors resection. The clinical results suggested that surgery methods involving pubis (type A) and ischium (Type B) are safe and feasible. However, further researches should be conducted to verify our classification system.