Current Procedural Terminology Codes Combined With Hip and Femur Diagnosis-Related Groups Provide a More Accurate...

Diagnosis-Related Groups (DRGs) have become the basis of the Center of Medicare & Medicaid Services (CMS) hospital reimbursement system. Wide variability of patient factors and procedures bundled into a single DRG may contribute to significant cost variation and limited usefulness when analyzing economic performance. This investigation sought to analyze variation in hip and femur fracture inpatient costs as assessed by DRG and Current Procedural Terminology (CPT) codes.

Patients age ≥ 18 treated with operatively managed fractures of the hip and femur at a Level 1 trauma center from 2019 to 2021 were retrospectively reviewed. Patients categorized as DRG 480, with major comorbidity/complication; 481, with comorbidity/complication; and 482, without comorbidity/complication were eligible. Seven common CPT codes were analyzed after exclusion of patients with low frequency CPT codes (< 50 instances). The primary outcome was total direct costs by DRG and CPT codes. Total direct costs were compared among CPT codes within each DRG using an ANOVA model. Costs were also compared among DRGs for each CPT code. Secondary outcomes include comparison of total direct costs by surgeon within DRG and within each CPT code.

A total of 896 patients were analyzed. Significant variation in costs was observed among different DRGs for specific CPTs (p < 0.001). Similarly, notable variation in total direct costs was recorded among different CPTs within each given DRG (p < 0.001). Although cost variations were observed between surgeon and DRG (p < 0.001), no significant interaction was observed once specific procedural (CPT) data were included in the model (CPT 27245: F = 1.077, p = 0.378; CPT 27506: F = 0.934, p = 0.504).

While direct costs are influenced by the complexity of DRG assignment within the hip and femur fracture DRG family, the data may be limited in its applicability given the heterogeneity of patients and procedures captured within each DRG. Evaluating costs using a DRG-CPT combination, instead of DRG alone, may provide a more comprehensive and accurate understanding of costs of care.

Economic and Decision Analyses Level III.