Preoperative radiographical degenerative lumbar spondylolisthesis does not affect clinical outcomes of total hip arthroplasty.

INTRODUCTION

Degenerative lumbar spondylolisthesis (DLS) is sometimes found in preoperative spine radiographs before total hip arthroplasty (THA). However, whether DLS affects the clinical outcomes of THA and whether the slip is improved by THA remain unclear. This study investigated the clinical outcomes of THA in patients with DLS and change in the slip percentage of DLS after THA.

MATERIALS AND METHODS

We included 369 patients who underwent primary THA due to hip osteoarthritis between December 2015 and February 2022. The patients were classified into the DLS or non-DLS group by evaluating preoperative whole-spine radiographs in the standing position. Preoperative sagittal spinal parameters, preoperative and 1-year postoperative Harris hip score, Oxford hip score, and slip percentage of DLS were evaluated. Multiple regression analysis was performed to identify the factors associated with DLS.

RESULTS

Of the 369 patients, 101 (27.4%) were classified into the DLS group. Multivariate analysis revealed that age (odds ratio (OR) per unit: 1.04, p < 0.01) and pelvic incidence (PI) (OR per unit: 1.04, p < 0.01) were significantly associated with DLS. Preoperative and postoperative clinical outcomes between the DLS and non-DLS groups were not significantly different. The preoperative and postoperative percentages of slip in the DLS group did not change significantly from 16.9% ± 6.2% to 16.7% ± 6.7% (p = 0.47). Patients with slip progression ≥ 2.5% of slip percentage were 19 (18.8%), who were younger (p = 0.02) and had higher PI (p = 0.01) and sacral slope (p = 0.03) than those with slip improvement.

CONCLUSIONS

Age and PI were significantly associated factors for DLS. The slip was not improved after THA. The clinical outcomes of THA in the DLS group were not affected. Longer-term follow-up studies are essential to elucidate the hip-spine relationship.