Lateral femoral wall thickness in trochanteric hip fractures: a systematic review.

Background: Thin lateral femoral wall has been investigated as a sign of instability in trochanteric hip fractures, necessitating lateral wall reconstruction or the use of a cephalomedullary nail (CMN). Various cut-off values have been proposed to guide implant choice. This review aims to determine the clinical significance of the lateral femoral wall thickness (LWT) in trochanteric hip fractures and identify an optimal cut-off value for increased risk of lateral wall (LW) fracture when using Dynamic Hip Screw (DHS).

Methods: A comprehensive search was conducted in databases including Medline, Embase, and the Cochrane library up to July 2023. A predefined strategy was employed, with 5 eligible studies critically appraised using the methodological index for non-randomized studies (MINORS) criteria. Outcomes assessed encompassed the standardised mean difference (SMD) of LWT between the LW fracture and non LW fracture groups, aggregate LWT mean in LW fracture group, and the relation between AO/OTA fracture type with LW fracture utilising the chi-square test.

Results: Among 481 patients from 5 studies, 112 experienced LW fractures, while 369 did not postoperatively. Analysis indicated a significantly lower LWT in the LW fracture group (SMD -1.13, I² = 41.3%, p = 0.146). The mean LWT in the LW fracture group was 18.2 mm, with a 95% confidence interval of 17.29-19.10 mm.

Conclusions: A preoperative thin lateral femoral wall is a critical predictor of fixation failure and suboptimal functional outcomes when using a DHS. Thorough evaluation of pre- and intraoperative x-rays is essential. CMN is recommended over DHS in cases with LWT measurements <19 mm.