Modified direct anterior approach facilitate surgical treatment of irreducible lesser trochanter splitting intertrochanteric femoral fractures: surgical techniques and preliminary results

Lesser trochanter splitting intertrochanteric femoral fractures (LTSIFF) present significant challenges in surgical management due to cortical locking and soft tissue incarceration. The direct anterior approach (DAA) is commonly favored for femoral head or neck fractures; however, there is a paucity of literature regarding its application in LTSIFF. This study aimed to assess the efficacy and safety of a modified DAA in the treatment of irreducible LTSIFF, with specific reference to anatomical characteristics and treatment strategies. A total of 22 eligible patients with irreducible LTSIFF were treated at our trauma center from January 2020 to October 2024. These fractures were unmanageable with closed reduction maneuvers and required open reduction via soft tissue release (including cutting the strangulated iliopsoas tendon) and cortical unlocking through a modified DAA. Short cephalomedullary nails (CN) were subsequently used for fixation. Demographic data, surgical characteristics, radiological findings, and functional outcomes were collected and analyzed. The mean age of the patients was 64.6 ± 20.3 years, with 17 males (81.8%) and 5 females (18.2%) in the cohort. The most common injury mechanisms were falls (12/22, 54.5%) and traffic accidents (8/22, 36.4%). The mean operation time was 78.5 ± 12.3 min, and the mean intraoperative blood loss was 156.3 ± 45.2 mL. Auxiliary devices, including clamps, periosteal elevators, and hooks, were used to release cortical locking and soft tissue incarceration. Among these procedures, soft tissue release was performed in 19 cases, whereas tendon cutting was utilized in only 3 cases. All patients received CN implantation. The mean fracture reduction quality (FRQ) score was 3.6 ± 0.6 across all cases, and the mean time to weight-bearing (TWB) was 3.8 ± 0.4 weeks. All patients were followed up for an average of 15.3 ± 1.9 months. Clinical fracture union was achieved at a mean of 10.4 ± 1.8 weeks, with radiographic union occurring at a mean of 15.1 ± 2.4 weeks. No helical blade cutout was observed on radiological examinations. The mean tip-apex distance (TAD) was 23.6 ± 2.6 mm, and the mean calcar-referenced tip-apex distance (Cal-TAD) was 21.6 ± 2.6 mm. Anteromedial cortical support was successfully achieved in all cases except one. At the final follow-up, the average Harris Hip Score (HHS) was 87.59 ± 5.68, and the average Barthel Index was 89.59 ± 7.96. Aside from two cases of superficial fat liquefaction at the modified DAA incision site, no other complications were observed in the current study. The modified DAA appears to improve fracture reduction quality, particularly anteromedial cortical support, and may be associated with favorable clinical outcomes in patients with irreducible LTSIFF. With favorable and safe surgical exposure for soft tissue release and cortical unlocking, and no significant complications observed, this approach shows potential for managing this specific fracture type. However, additional comparative studies are needed to validate these preliminary findings.