The cost of adverse events from knee surgery in the United Kingdom: An in-depth review of the National Health Service Litigation Authority database

• We examined the costs and trends of all knee surgery claims against the NHS.
• Of 515 cases (total 4609), 298 (58%) involved total knee replacements (TKRs).
• Litigation success rates were highest for technical errors following TKR.
• A concerning number of claims involved incorrect prosthesis/prosthesis.
• Missed diagnosis also resulted in substantial pay outs.

BackgroundThere has been a significant rise in the number and value of claims against the National Health Service (NHS), with limited studies on litigation in orthopaedic surgery and none in knee surgery alone. We aimed to examine claims against the NHS involving all aspects of knee surgery with respect to costs and trends.Clinical relevanceTo raise awareness of the reasons for litigation in knee surgery, thus potentially improve patient care and reduce future claims.MethodsWe analysed the NHS litigation authority (NHSLA) database for all orthopaedic surgery claims reported to the NHSLA between 2005 and 2010, with calculation of litigation success rates and odds ratios for those relating to knee surgery.ResultsThere were 515 cases identified from the 4609 orthopaedic cases in the NHSLA database (11.2%): 298 (58%) involving total knee replacements (TKRs), 11 (2%) involving unicondylar knee replacements, and 90 cases (30%) remaining open. The total pay out for closed cases was £10.45 million and amputation following TKR resulted in the highest single pay out. Litigation success rates for claimants were highest for retained drains (100%), incorrect prosthesis/prosthesis size (78%), renal failure (75%), poor outcome requiring further surgery (74%) and malalignment (71%). There were also 60 cases of delayed diagnosis which resulted in pay outs totalling £2.90 million. Based on these data, projected future pay out costs for the open TKR cases were estimated to be £2.71 million.ConclusionLitigation success rates for TKR were highest following technical errors such as malalignment compared to events less under the surgeon's control, such as infection. The number of claims involving incorrect prosthesis/size continues to be of concern. Despite the increased availability of imaging modalities, missed diagnosis also resulted in substantial pay outs.