Letter to the Editor: Regarding "High Prevalence of Spino-pelvic Risk Factors in Patients With Postoperative Hip Dislocations".

We read with great interest the publication by Vigdorchik et al., ‘High Prevalence of Spino-pelvic Risk Factors in Patients with Postoperative Hip Dislocations’ [ [1] Vigdorchik J.M. Madurawe C.S. Dennis D.A. Pierrepont J.W. Jones T. Huddleston 3rd, J.I. High prevalence of spinopelvic risk Factors in patients with post-operative hip dislocations. J Arthroplasty. 2022; Google Scholar ]. The authors conducted this case-control study in 48 patients who had one or more postoperative dislocations after primary hip arthroplasty. They measured pelvic tilt (PT) and lumbar flexion (LF) in standing and flexed-seated lateral x-rays and pelvic incidence, supine PT, pelvic incidence, and acetabular cup orientation in computed tomography scans. They calculated ‘adverse pelvic mobility’ of the cohort and the prevalence of ‘at risk’ spino-pelvic parameters according to literature thresholds, and finally compared the results to a previously published cohort of 9,414 total hip arthroplasty (THA) patients. They concluded that excessive standing posterior PT, low LF, and a severe sagittal spinal deformity, are more prevalent in unstable THAs.