Iatrogenic gluteus medius muscle insertion injury while trochanteric entry nailing due to trochanteric fractures: a comparative study in forty patients with gray-scale ultrasound and shear-wave elastography.

introductionTrochanteric entry nailing potentially causes damage to the gluteus medius (GM) tendon. The aim of this study is to determine the amount of iatrogenic damage to the tendon during reaming by measuring the thickness and stiffness of the GM muscle in patients with trochanteric fractures who are treated with trochanteric entry nails using gray-scale ultrasound (GSUS) and shear-wave elastography (SWE).

methodsThickness and stiffness values of bilateral GM muscles in 40 patients with trochanteric fractures treated with PFN-A were measured using GSUS and SWE at post-operative sixth week or later. Harris Hip Scores and bilateral active hip abduction measurements of the patients were recorded. The data was analyzed using statistical methods to assess the extent and amount of iatrogenic injury that occurred during trochanteric entry.

resultsMean age of the patients was 70. Thirty-three fractures occurred with low-energy trauma. In the SWE evaluation, there was no statistically significant difference between ipsi- and contralateral GM muscle thickness measurements or ipsi- and contralateral GM muscle stiffness measurements. Also, the difference between the clinical evaluation results of the ipsi- and contralateral hip functions was not statistically significant. DISCUSSION: In this study, we used the Harris Hip Score and hip abduction range of motion in addition to SWE and GSUS in order to assess the patients' functional status. There are studies in the literature that report significant injury to the GM tendon with cephalomedullary nailing. The majority of these studies are cadaver studies with only clinically irrelevant or uncertain evidence. In this study, we aimed to evaluate the potential negative effects of the iatrogenic damage to the bone-tendon junction during nailing, by measuring the stiffness (consistency) and atrophy of the GM muscle alongside the functional evaluation.

conclusionWe have found no statistically significant difference between operated and intact side GM muscles in terms of stiffness, atrophy, and functional evaluation in patients with TFs treated using PFN-A. The results of our study should not be interpreted as trochanteric entry nailing does not cause any damage on the GM tendon.