[Universalization of primary health care: "heart" of health reform in Chile].

The surgical treatment of hip fracture in elderly patients has long been debated. Orthopedic surgeons have extensive experience in managing this injury. In contrast to intertrochanteric fractures of the femur, femoral neck fractures (FNF) exhibit superior clinical outcomes with joint replacement compared to internal fixation. Total hip replacement (THR) is an uncommon procedure for the displaced FNF in elderly patients due to the high risk of mortality and morbidity associated with old age, osteoporosis, mental status, medical comorbidities, and postoperative complications. The goal of treatment is to achieve complete rehabilitation and return to the individual’s pre-injury condition. However, one of the greatest concerns in the surgery of FNF with THR is the assumed increased risk of dislocation. The development of femoral stem designs, including decreased neck-shaft angle and modular stems, along with new concepts for acetabular sides such as larger diameter heads and dual-mobility implants, may help increase construct stability and decrease dislocation. Also, an extended medial offset (MO) stem, which is related to the abductor muscle moment arm, has an effect on reducing wear on bearing surfaces, implant loosening, and dislocation rates. However, the recovery of abductor muscle strength and functional outcomes after THR with an extended femoral offset (FO) cemented stem in FNF in elderly patients is not well documented. We conducted a retrospective study to verify the relationship between an extended FO cemented stem and abductor muscle strength, joint stability by increasing the abductor lever arm, leg length, and function following THR for FNF in elderly patients. This study was approved by the Institutional Review Board of Wonkwang University Hospital (IRB No. 2025-12-006). This study was conducted as a retrospective study, and the requirement for informed consent was waived by the Institutional Review Board.