Do Spinopelvic Parameters Relate with Secondary Hip Spine Syndrome in Secondary Hip Arthritis?

The prevalence of low back pain (LBP) with primary osteoarthritis (OA) hip undergoing total hip replacement (THA) has been studied. However, secondary OA hip affects younger individuals where changes in the sagittal spinal parameters (SSPs) could be reversible to reduce LBP. The study aims to document changes in clinical and radiological parameters following THA.

Thirty patients with secondary OA hip were included in the prospective analysis, excluding anyone with previous spine/hip surgery of known spinal diseases, including deformity, inflammatory or infective pathology. Visual analog scale for (VAS) hip and LBP, Oswestry disability index (ODI), and Harris core (HHS) along with SSPs were measured at baseline and three months and analyzed.

Mean age was 42.8 ± 8.9 years which 17 unilateral (U/L) and 13 bilateral (B/L) OA. Overall, no significant changes were seen in SSPs that included pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), pelvic incidence-lumbar lordosis (PI-LL) was seen except for an improvement in the sagittal vertical axis (SVA) [40.22 ± 36.67 to 24.06 ± 21.93, p < 0.001]. However, clinical variables such as VAS hip and LBP, ODI, and HHS improved post-hip THA. Similar findings were seen in sub-group analysis when U/L affected were compared to B/L affected.

The sagittal SSPs except SVA does not change significantly following THA in patients with secondary OA, though LBP improves clinically. Hence, we assume routine measurement of these parameters is not mandatory when planning for THA in these patients.