Surgeon Experience in Hip Arthroscopy Affects Surgical Time, Complication Rate, and Reoperation Rate: A Systematic Review on the Learning Curve

Purpose: To systematically review the literature to (1) identify the reported learning curves associated with hip arthroscopy and (2) evaluate the effect of the stated learning curves on outcomes, such as complication rates, surgical and traction time, reoperation rates, and patient-reported outcome score (PRO) improvements.

Methods: Two independent reviewers screened the PubMed-MEDLINE, Embase, and Cochrane Library electronic databases from inception to January 2020 according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The following search algorithm was used: "hip arthroscopy" paired with "learning curve," "competence," "experience," "performance," and "motor skills." Data regarding study characteristics, patient demographic characteristics, PROs, and learning-curve analyses were collected.

Results: We identified 15 studies that reported the impact of the learning curve on surgical progress or clinical outcome measures. Measures of the surgical process included surgical and traction time, as well as fluoroscopy time, whereas clinical outcome measures encompassed PROs, complication rates, and reoperation rates. Three studies reported that the learning curve plateaued at 30 cases, but other studies suggested cutoff points ranging from 20 to 519. Operative time (75-119 minutes vs 45-99 minutes), traction time (55-127 minutes vs 54-112 minutes), complication rates (0.5%-43.3% vs 0.5%-18.0%), revision arthroscopy rates (3.3%-10% vs 1.0%-4.2%), and rates of conversion to total hip arthroplasty (12.2%-22.5% vs 1.5%-3.7%) decreased as surgeons gained more experience. Favorable PROs were observed throughout the surgeons' experience.

Conclusions: Progression along the learning curve of hip arthroscopy led to decreases in complication rates, surgical and traction time, and reoperation rates. PROs benefited from surgery throughout the learning curve. Currently, there exists a wide spread of cutoff numbers proposed to achieve proficiency, ranging from 20 to over 500.