This study reports overall significantly higher complications rates using a payer-based database following hip arthroscopy as compared to traditional published observational trials that usually come from high volume surgeons and centers.
The incidence of hip arthroscopy continues to increase as the understanding of hip pathology and technical advances improve. Recent studies have investigated outcomes and complications associated with hip arthroscopy primarily through the use of small-scale, observational trials, particularly from high volume accomplished surgeons and/or centers. The purpose of this study was to investigate complication trends associated with hip arthroscopy using a payer-based US national database and compare them with published series from experienced surgeons.
Patients who underwent hip arthroscopy were identified from a publicly available database of over 18 million patients with both private insurance and Medicare Advantage charge data. Patients having undergone hip arthroscopy were searched for Current Procedural Terminology (CPT) and International Classification of Diseases, Ninth Revision (ICD-9) codes associated with significant complications such as PE, DVT, infection, fracture and dislocation, as well as conversion to total hip arthroscopy (THA). Incidence rates for the general database population to be used as a control were also determined for a subset of complications including proximal femur fractures, conversion to THA, and hip dislocations. Statistical significance was set at alpha less than 0.05.
Overall, 2581 hip arthroscopies were performed over an 8-year period. The rates of major and minor complications within a 1-year post-operative period were 1.74% and 4.22%, respectively. Heterotopic ossification (2.85%) was the most common complication followed by bursitis (1.23%), proximal femur fracture (1.08%), hip dislocation (0.77%), DVT (0.46%), superficial wound infection (NR) and nerve injury (NR). The rate of proximal femur fracture, hip dislocation and DVT were all significantly greater than the rates published in the English literature by high volume centers. Rate of conversion to THA within 1 year of hip arthroscopy was 2.85% and after 5 years was 4.74%. The relative risk of requiring a THA following hip arthroscopy at 1 year was significantly higher when compared to the general population for patients both younger and older than 50 years of age (RR 57.66 for patients < 50 years (95%CI 35.36 to 94.02, p<.001), RR 22.05 for patients > 50 years (95%CI 16.11 to 30.18, p< .001)). The relative risk of sustaining a proximal femur fracture within 1 year was also significantly higher following hip arthroscopy (RR 18.02 for patients < 50 years (95%CI 9.71 to 33.43, p<.001), RR 2.23 for patients > 50 years (95%CI 1.30 to 3.82, p<.001)).
This study reports overall higher complications rates using a payer-based database following hip arthroscopy as compared to traditional published observational trials. Additionally, hip arthroscopy is shown to be associated with significantly higher rates of hip dislocations, conversion to THA, as well as an increased incidence of proximal femur fractures, especially in patients younger than 50 years. The high incidence of hip fractures found in our study is concerning given the possible underreporting in other studies. As there were only 2,581 hip arthroscopies performed over the 8-year period of this database, it would suggest most of these hip arthroscopies were performed by surgeons that do not perform a high volume of hip arthroscopies.