Summary

Two-year reoperation and total hip arthroplasty conversion rates for 1407 primary hip arthroscopies undertaken by a single senior surgeon identified low rates throughout the learning curve and association with pre-surgery patient-reported pain and disability during regular daily activities rather than with sport-specific measures.

Abstract

Background

Despite the growing evidence on outcomes following arthroscopic surgery for femoroacetabular impingement (FAI), information about patients who subsequently present for reoperative surgery or total hip arthroplasty (THA) is relatively modest.

Purpose

To determine whether differences in patient characteristics or experience over time of a single surgeon affects reoperation or THA conversion rates with 2-year minimum follow-up.

Methods

Data collected prospectively from patients receiving primary hip arthroscopy for FAI by a single surgeon between June 2005 and August 2016 were reviewed to identify reoperation and THA conversion rates according to patient characteristics and the number of prior hip arthroscopies performed by the surgeon. Differences in age, gender, body mass index (BMI), severity of osteoarthritic changes or chondral damage, surgeon experience and pre-operative patient-reported 12-item International Hip Outcome Tool (IHOT12), Non-Arthritic Hip (NAH) and Hip Osteoarthritis Outcome (HOO) scores were compared between hip joints that underwent subsequent surgery and those that did not.

Results

The 2-year reoperation and THA conversion rates for 1407 primary surgeries, in 48.2% female patients, were 2.5% and 2.1% respectively. Total reoperation and THA conversion rates were 7.2% and 3.8% with an average follow-up 5.2 years. Those who underwent subsequent surgery on the same hip (either reoperative or THA) compared to those who did not were older, 37.8 ± 13.1 years (mean ± SD) versus 34.7 ± 12.0 years (P = 0.006); were more likely to have more severe chondral damage, 14.6% versus 12.7%, or indications of hip osteoarthrosis, 29.1% versus 12.1%, (P < 0.001); and reported a worse preoperative NAH total score: 58 ± 21 compared to 63 ± 18 (P = 0.005), but not preoperative IHOT12 total score (38 ± 22 versus 40 ± 20) or body mass index. The contrasting pattern of findings for different patient-reported scores was mirrored across dimensions of HOO, with pain (P = 0.03), daily living (P = 0.005) and quality of life (P = 0.04) subscales differing between those who had reoperative or THA surgery and those who did not, but not symptoms or sports subscales. Surgeon experience was less for those who received subsequent surgery compared to those who did not, with 586 ± 412 versus 760 ± 430 prior hip arthroscopies undertaken (P < 0.001) respectively, but this effect disappeared when correction was made for the intervening time period by comparing only those who did and did not have subsequent surgery within 2 years. Differences retained statistical significance when reoperative and THA surgery were analysed separately, except for patient-reported outcomes that did not differ for smaller numbers of recipients of THA surgery compared to no conversion.

Conclusion

Low rates of complications requiring either reooperative or THA conversion surgery are maintained following hip arthroscopy throughout the experience of a senior surgeon. Patient-reported scales that assess pain during regular daily activities may be more predictive of the need for subsequent surgery than those pertaining to sporting activities or general symptoms.

KEYWORDS:
Femoracetabular Impingement; Learning curve; Arthroscopic surgery; Revision surgery; Reoperation; Hip Joint; Hip joint replacement