Abstract
Background
Total Knee Replacement (TKR) is technically demanding, time consuming and has higher complication rates in super obese (BMI>45) patients. Bariatric surgery can be considered for such patients prior to TKR although its effect on complications is unknown.
Methods
All patients who underwent bariatric surgery and a TKR in the NHS in England between 2005 and 2009 were included. Hospital episode statistics data in the form of OPCS, ICD10 codes were used to establish 90-day DVT, PE and mortality rates (inpatient and outpatient). In addition, readmission to orthopaedics, joint revision and ‘return to theatre for infection’ rates were also established. Code strings for each patient were examined in detail to ensure the correct gastric procedures were selected. Fifty-three patients underwent bariatric surgery then TKR (44-1274 days) (group 1). Thirty-one patients underwent TKR then bariatric surgery (33-1398 days) (group 2).
Results
In the 53 patients that underwent bariatric surgery first there was 1 DVT, no PE and 1 death at 90 days following knee replacement. There were no orthopaedic readmissions within one year of TKR, no revision at 18 months and no knee washouts for infection.
In the 31 patients that underwent TKR first there were no DVT, PE or deaths at 90 days. There were four orthopaedic readmissions (12%) within 30 days of TKR and two infections of the knee replacement.
Overall, one-year infection rate and readmission were higher if TKR was performed prior to the bariatric surgery. The statistical analysis is difficult due to small number of patients.
Conclusions
This data suggests that timing of bariatric surgery appears to be crucial. Although complication rates appear high in patients who undergo both procedures, performing bariatric surgery first appears to reduce that risk of local complications.
