The Influence of Pain in Other Major Joints and the Spine on 2-Year Outcomes After Hip Arthroscopy

Purpose: To determine whether patients who have pain in other major joints or the spine have poorer postsurgical outcomes than patients without comorbid orthopaedic pain.

Methods: We performed a review of a prospectively maintained institutional surgical registry of patients who underwent hip arthroscopy between January 1, 2012, and July 16, 2015, by a single surgeon, with a minimum of 2 years of postoperative follow-up. A musculoskeletal morbidity (MSM) score was assigned to each patient preoperatively based on the presence of pain in other joints and the spine (grade 1, hip only; grade 2, hip and other major joints without spine; grade 3, hip with spine; and grade 4, hip and other major joints with spine). Preoperatively and at 2 years postoperatively, functional outcomes were measured using the Hip Outcome Score-Activities of Daily Living (HOS-ADL), and the percentages of patients achieving a minimal clinically important difference (MCID) and patient-acceptable symptom state (PASS) were calculated.

Results: In total, 821 patients were identified, of whom 700 (85.3%) completed 2-year follow-up. Preoperatively, MSM grade 1 patients had a higher HOS-ADL than grade 2 patients (P = .02), but there was no difference between grade 1 and grade 3 patients (P = .63) or between grade 1 and grade 4 patients (P = .14). Likewise, there was no difference in the preoperative HOS-ADL among grades 2, 3, and 4. Patients with MSM grades 1 and 2 were younger than those with grades 3 and 4. At 2 years postoperatively, MSM grade 1 patients had higher HOS-ADL values than grade 3 (P = .01) and grade 4 (P = .02) but not grade 2 (P = .07) patients. Overall, 84% of patients showed an MCID and 72% of patients achieved a PASS with regard to the HOS-ADL. There were no statistically significant differences among MSM grades in terms of the MCID or PASS.

Conclusions: Overall, 84% of patients improved with hip arthroscopy by MCID criteria for the HOS-ADL. Patients with no pain in other joints (MSM grade 1) had better 2-year postoperative HOS-ADL values after hip arthroscopy than patients with spine pain (grades 3 and 4). However, there were no significant differences in the MCID or PASS among patients with regard to MSM grade. A total of 40.5% of patients who underwent hip arthroscopy had pain in another joint. A limitation, however, is that there is potential for a type II error, in that there may not have been a sufficient number of patients studied to detect a significant difference in outcome among patients with different grades of musculoskeletal comorbidity.

Level of evidence: Level IV, therapeutic case series.