Stress fractures of the femoral neck in adults: an observational study on epidemiology, treatment, and reoperations from the Swedish Fracture Register

Abstract

Background and purpose: Stress fractures of the femoral neck (sFNFs) are uncommon injuries. Studies on sFNFs are rare. We describe the demographics, classification, treatment, reoperation rates, and mortality in a cohort of sFNF patients from the Swedish Fracture Register (SFR). Patients and methods: We included 146 patients ≥ 18 years of age with an sFNF registered in the SFR between 2011 and 2020. The cohort was linked with the Swedish Arthroplasty Register and reviewed using medical records and radiographs. We assessed the presence of disorders of bone remodeling, duration of symptoms, fracture classification, treatment, reoperations, and mortality. Results: The mean age was 58 years (21–96), 75% were women and the median duration of symptoms was 23 days (1–266). 40% of patients had disorders of bone remodeling. 54% were undisplaced (uFNF), 30% displaced (dFNF), and 16% basicervical (bFNF). 14% of patients < 60 years were treated nonoperatively, by internal fixation (IF) in 77% and by arthroplasty in 10%. Patients ≥ 60 years weretreated nonoperatively in 10%, IF in 40%, and arthroplasty in 49%. Nonoperative treatment was reserved for uFNFs or bFNFs, resulting in 35% receiving late surgery. The overall secondary or late surgery rate was 19%. Mortality was 2% at 90 days and increased to 3% at 1 year. Interpretation: sFNF has a biphasic age distribution. One-third of patients presented with a displaced FNF and those managed nonoperatively for an undisplaced sFNF were at risk of late surgery. The mortality rates for patients with these injuries was low.

Bilateral Stress Fracture of the Femoral Neck: A Case Report

“…Incidence rates in traumatic versus stress fractures may differ due to differences in surrounding tissue damage from trauma and differences in patient characteristics. Furthermore, risk of avascular necrosis and nonunion is not completely eliminated with internal fixation and fixation failure can occur [18]. Two relatively large retrospective MRI studies have identified prognostic fracture characteristics that may help guide the surgeon in choice of treatment.…”

“…The incidence rate of sFNFs has been found to be 100/100.000 personyears in a military population, while bilateral sFNFs are much rarer and not presented by an incident rate in the literature. Available literature largely focuses on athletes and military personnel [1][2][3][4][5][6][7][8][9][10][11][12][13] as protentional candidate for SFNF. Prospective series show that 8% of stress fractures in competitive track and field athletes are located in the femur and 5% of stress fractures in a military population are in the femoral neck.…”

“…87% had anterior groin pain and 19% nightly pain and was preceded by a long run or march in 40% of patients. Tenderness to inguinal palpation was present in 62% of cases and 79% had pain in extremes of hip range of motion while heel percussion very rarely elicited pain [1][2][3][4][5][6][7][8][9][10][11][12][13][14].…”

Uncommon Twist: Femoral Neck Stress Fracture in a High-Performance Athlete With an Incidental Diagnosis of Femoroacetabular Impingement

“…Femoral neck stress fractures (FNSFs) are rare injuries that often result in delayed diagnosis due to initial symptoms being overlooked [ 1 ]. They represent approximately 1%-2% of all femoral neck fractures, 3%-5% of all stress fractures, and account for about 3% of sport-related events [ 2 , 3 ]. FNSFs demonstrate a bimodal distribution, affecting both a younger, active demographic and an older population with potentially compromised bone quality or impaired bone repair mechanisms [ 4 ].…”

“…FNSFs demonstrate a bimodal distribution, affecting both a younger, active demographic and an older population with potentially compromised bone quality or impaired bone repair mechanisms [ 4 ]. In the younger cohort, FNSFs are mainly observed among military personnel and high-performing athletes, commonly linked with a rapid increase in physical activity and endurance exercise [ 1 , 2 , 5 - 7 ].…”