MRI-only occult geriatric hip fractures: is displacement common with nonoperative treatment?

Introduction Although surgical fixation is routinely recommended for geriatric hip fractures, nonoperative treatment may be an option for certain stable fracture patterns. Occult hip fractures are nondisplaced fractures not evident on radiographs, but display intraosseous edema on MRI. Our aim is to report the rate of nonoperative treatment failure in patients with occult geriatric hip fractures. Methods All nonoperatively treated femoral neck or intertrochanteric femur fractures (AO/OTA 31A and 31B) from 2003 to 2018 were identified. Patients older than 65 years with negative radiographs but a hip fracture evident on MRI were included. Patients who died prior to fracture displacement or union were excluded. Charts and imaging were reviewed for demographic data, fracture type, clinical course, displacement, and whether corrective surgery was performed. Results Of 15 final study patients, there were 6 femoral neck and 9 intertrochanteric fractures. Two fractures displaced, both requiring surgery (2/15; 13.3%). Both displacements occurred in the femoral neck group (2/6; 33%) compared to none in the intertrochanteric cohort (0/9; 0%). This trend did not reach statistical significance ( p = 0.14). Conclusion Thirty-three percent (2/6, 33%) of femoral neck fractures displaced and required surgery. The remainder of the cohort (13/15, 87%) healed without complication, including all of the intertrochanteric fractures (9/9, 100%). Although this difference did not reach statistical significance, the results may better inform treatment discussions for geriatric patients with occult hip fractures diagnosed by MRI. Level of evidence Level III.