LESSONS FROM NUCLEAR POWER: A DEEPER UNDERSTANDING OF ERROR AND TEAMWORK IN ANTERIOR APPROACH TOTAL HIP ARTHROPLASTY

When learning the anterior approach THA (AA-THA), the risk of an early complication doubles. Little is known about the intraoperative processes which may contribute to these problems. The surgical team may also influence surgical error. This study uses Human Reliability Analysis (HRA), a technique used to prevent disaster in aviation and nuclear power, to investigate technical error in AA-THA. Sixty-two primary AA-THA operations were professionally filmed in 61 participants. 6 surgeons (3 experts, 3 learners) performed the operations. An expert derived task sequence analysis identified 10 operative phases. Video footage was analysed, and errors were classified using 10 error modes. Hazard zones, where errors occurred more frequently, were identified. Radiological errors were identified analysing postoperative radiographs. Performance of the wider surgical team was assessed using the NOTECHS II score and correlated with total error. Participants were followed up at 6 weeks to document adverse events. Mean age was 68.5 ± 9.2 years old, mean BMI 27.0 ± 5.6. 44 female, 17 male. 853 errors were recorded across 62 surgeries with a mean 13.8 ± 8.4 errors per case. Most errors happened during acetabular reaming (4.1 ± 4.0 per case), followed by femoral broaching (2.9 ± 3.3) and deep exposure of the hip (2.0 ± 1.6). Learning surgeons made double the total errors compared to experts (25 ± 11.4 vs 12.3 ± 6.9, p = 0.002). Three patients (4.9%) had post-operative femoral fractures. 35.5% of acetabular components were outside the safe zone, 27.4% had a leg length discrepancy > 5mm. As NOTECHs II score increased technical error reduced (Rs = -0.45 (95% CI: -0.64 to -0.21), p <0.001). Strongest subgroup correlations were the scrub nurse (Rs = -0.42 (95% CI: -0.62 to -0.18), p <0.001) and leadership subdomain (Rs = -0.46 (95% CI: -0.64 to -0.23), p <0.001). This study validates the HRA process. Hazard zones were: (1) Acetabular preparation, (2) Femoral broaching and (3) Deep exposure of the hip. Superior teamwork is associated with reduced intraoperative error. This detailed understanding of intraoperative error could guide interventions to reduce patient harm during the learning curve.