BackgroundAn upward trend is seen in a number of periprosthetic fractures. Their management often requires complex surgical intervention, expert skills and expensive equipment. Hospitals get paid according to Healthcare Resource Group (HRG) tariffs. HRG gets generated once diagnoses, Charlson comorbidity (CC) index score, surgical procedures, investigations and length of stay have been coded for. Coding departments consist of non-clinicians. Although auditing systems are in and made of internal and external auditors, we hypothesized that multiple errors can still occur which may result in significant financial losses.ObjectivesTo assess the accuracy of coding for management of periprosthetic fractures. To identify causes for inaccurate coding and assess the financial impact of highly complex trauma in a district general hospital (DGH).MethodsRetrospective comparative analysis of case notes for patients with an M966 diagnosis code (periprosthetic fracture) between 1st November 2017 and 1st November 2018. All cases were analysed and data for primary procedure, primary diagnosis, secondary procedures and secondary diagnosis, comorbidities and length of stay were extrapolated and re-coded using the same software in use by the coding team. Costs incurred for each surgically managed patient were calculated using a rough estimate of cost of each procedure. Finally, cost-effectiveness analysis was carried out by comparing our calculated figures to the actual final claim by our institution. ResultsTwenty-nine patients with the diagnosis of periprosthetic fracture were identified by the coding team using M966 code. A further case was identified by reviewing operating software (Operating Room Management Information System [ORMIS®]). In four cases (13.3 %), the primary diagnosis was coded incorrectly by the coding team. Overall coders accuracy for surgically managed patients (n=21) was 52% (n=11). This resulted in an estimated incurred loss of £25,000. Wrong/omitted site of surgery was found to be the most influential coder error with up to £8000 loss in one case (P<0.05). Cost-effectiveness analysis demonstrated the stark differences in costs for HRG tariffs when used in trauma setting vs non-trauma setting. Open reduction and internal fixation (ORIF) was associated with less financial loss to our trust with closer procedural costs to HRG tariff (average cost of £9200 for ORIF vs £22,030 for a massive endoprosthesis).ConclusionsSurgeons should carefully review codes for such complex procedures before or soon after surgery. Wrong/omitted site of surgery is the key cause for losses in our cohort, followed by inadequate recording of comorbidities. Coders can only code for what is documented. Following cost-effectiveness analysis our study highlights the need for HRG tariffs to be revised for such procedures. The cost of ORIF vs massive endoprosthesis should be noted, signifying the implant costs when such specialised revision surgery performed over less expensive ORIF surgery.