Clinical and functional comparison of dynamic hip screws and intramedullary nails for treating proximal femur metastases in older individuals

Objective To compare the outcomes of dynamic hip screws (DHS) and intramedullary nailing (IMN) in the treatment of extra-capsular metastatic carcinoma of the proximal femur. Methods A retrospective case analysis method was used to examine data of patients with proximal metastatic cancer of the femur who were treated with internal fixation in Department of Orthopaedics, Beijing Friendship Hospital, from January 2007 to December 2018. Blood loss, postoperative pain, functional score, length of stay, and survival rates were compared, and postoperative complications were assessed. Results Complete follow-up data were available for 33 patients. The mean follow-up period was 12.2±3.6 (range: 9-32) months and the average age was 72.3±4.7 (range: 59-83) years old. There were 20 females and 13 males. Twenty-three patients had undergone IMN and 10 DHS, according to bone defects and the patient's overall condition. The median survival time was 10 months in the IMN group and 11 months in the DHS group. Duration of surgery (t=-7.366, P<0.001) and length of hospital stay (t=-3.509, P<0.001) differed significantly between the two groups. There was one case of breakage of internal fixation in the IMN group. Conclusions There was no significant difference between DHS and IMN in terms of surgical efficacy. IMN and DHS were different in terms of surgical time and hospital stay. However, due to the limited number of cases in this study, multi-factor analysis has not been performed and needs to be further verified in future analysis. When developing a surgical plan, it is recommended to consider the patient's condition and the surgeon's experience.