Influence of pelvic incidence–lumbar lordosis mismatch on surgical outcomes of total hip arthroplasty: a retrospective cohort study

PMCID: PMC12174211

PMID: 40526273

DOI: 10.1007/s00590-025-04383-5

Journal: European journal of orthopaedic surgery & traumatology : orthopedie traumatologie

Publication Date: 2025-6-17

Authors: Ishikura H, Nishiwaki T, Kudo M, Minoji S, Tanaka T, et al.

Key Points

• PI-LL mismatch ≥ 10° is associated with altered spinopelvic parameters and poorer preoperative functional scores
• Preoperative mHHS total score: Matched group 56.5 ± 11.4 vs. Mismatch group 51.4 ± 14.0 (p=0.021)
• THA demonstrates consistent functional improvement across different spinopelvic alignments, supporting its effectiveness as a treatment modality

Summary

This retrospective cohort study investigated the impact of pelvic incidence-lumbar lordosis (PI-LL) mismatch on total hip arthroplasty (THA) outcomes in 167 patients. Patients were categorized into two groups based on a PI-LL mismatch threshold of 10°, revealing significant preoperative differences in spinopelvic parameters. The mismatch group demonstrated higher pelvic tilt, lower sacral slope, reduced spinal flexibility, and notably worse preoperative functional scores on modified Harris Hip Score (mHHS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC).

Critically, despite these preoperative variations, the study found no significant differences in postoperative outcomes between groups at 6 months. This suggests that THA can effectively improve patient function regardless of baseline spinopelvic alignment. The findings underscore the importance of individualized preoperative assessment while demonstrating the robust therapeutic potential of THA across varying spinopelvic configurations.