Treating pathological metastatic fractures of the humerus by compound osteosynthesis: a retrospective cohort study

Abstract

BackgroundThe number of malignant tumors is increasing as are bone metastases, such as those in the humerus. Arm function is important for an independent everyday life. In this study, compound osteosynthesis of metastatic fractures of the humerus is examined for its suitability in light of the competing risk of death. Materials and MethodsThis retrospective monocentric study includes a cohort of tumor patients who underwent primary compound osteosynthesis for pathological humeral fractures. The main endpoint was the continued existence of compound osteosynthesis using competing risk analysis (CRA) to contrast failure and death. Failure was defined as mechanical failure of the osteosynthesis construct like re-fracture or plate-and-screw dislocation or loosening, which provides an indication for re-intervention. Other complications are also described. ResultsWe included 36 consecutive patients (64% male, mean age 71.6 yrs.) from September 2007 to October 2020. In 58% of the cases, the left humerus was fractured. Lung carcinoma was the most common cause of bone metastases (27.8%). Compound osteosynthesis was performed with a median delay of five days after diagnosis of the pathologic fracture. Postoperative complications occurred in seven of the 36 patients (19.4%): radial nerve palsy (n = 3), postoperative hematoma (n = 2), re-fracture (n = 2) and screw loosening (n = 1). Few mechanical failures (8.3%) occurred within the first year; only one patient needed revision of the osteosynthesis (2.8%). Median patient survival after compound osteosynthesis was 26.6 weeks. CRA showed that for up to two years, the risk of death is clearly dominant over the risk of osteosynthesis failure from surgery. ConclusionOur study shows that compound osteosynthesis of the humerus is a suitable option for patients with pathologic humerus fractures. Compound osteosynthesis of the humerus usually survives the duration of malignant tumor disease.