Medical Services and Associated Costs Vary Widely Among Surgeons Treating Patients With Hand Osteoarthritis

There are substantial variations in medical services that are difficult to explain based on differences in pathophysiology alone. The scale of variation and the number of people affected suggest substantial potential to lower healthcare costs with the reduction of practice variation. Our study assessed practice variation across three affiliated urban sites in one city in the United States and related healthcare costs following the diagnosis of hand osteoarthritis (OA) in patients.

(1) What are the factors associated with increased costs and surgery in the first year after diagnosis of hand OA? (2) How much practice variation exists among hand surgeons in terms of the number of patient visits, use of imaging tests, use of injections, occupational therapy use, and surgery? (3) What proportion of total cost is accounted for by patients who consult with an additional provider?

Patients receiving a new diagnosis of primary hand OA between January 1, 2007, and December 31, 2011, were identified from the research database of three affiliated urban hospitals in a single city in the United States. We included 2814 patients (69%, 1929 women) treated by six hand surgeons. We recorded all visits, imaging tests, injections, occupational therapy visits, and surgical procedures in the first year after that diagnosis. Costs were extracted from the Medicare Physician Fee Schedule. Reliability of the database was assessed by manual checking of 120 patient charts (4.3% of all data); reliability was determined to be 94% (113 of 120) for diagnoses, 97% (116 of 120) correct surgeon, 100% (120 of 120) second surgeon, 99% (278 of 282) visits, 99% (132 of 134) imaging procedures, 92% (11 of 12) injections, 95% (21 of 22) surgical procedures, and 85% (102 of 120) prescribing occupational therapy.

Predictors of increased costs included younger patient age (regression coefficient [β] −3.5, semipartial R² 0.0049, 95% confidence interval [CI] −5.4 to −1.7, p < 0.001), seeing a second surgeon (β 283, semipartial R² 0.0095, 95% CI 176–391, p < 0.001), and specific surgeons (surgeon 1: β −243, semipartial R² 0.026, 95% CI −298 to −188, p < 0.001; surgeon 2: β −177, semipartial R² 0.0090, 95% CI −246 to −109, p < 0.001; surgeon 6: β 124, semipartial R² 0.0050, 95% CI 59–189, p < 0.001) (adjusted R² = 0.056). Similarly, factors associated with increased surgical intervention included younger patient age (β −0.0026, semipartial R² 0.0071, 95% CI −0.0037 to −0.0015, p < 0.001), male sex (β 0.041, semipartial R² 0.0028, 95% CI −0.069 to −0.012, p = 0.005), seeing a second surgeon (β 0.16, semipartial R² 0.0091, 95% CI 0.094–0.22, p < 0.001), and specific surgeons (surgeon 1: β −0.14, semipartial R² 0.026, 95% CI −0.18 to −0.11, p < 0.001; surgeon 2: β −0.13, semipartial R² 0.014, 95% CI −0.17 to −0.091, p < 0.001). There were large variations in the average number of visits (1.5-fold), imaging tests (threefold), use of injections (51-fold), occupational therapy (twofold), and surgery rates (sevenfold) among providers. One hundred twenty patients (4.3%) consulted a second surgeon within the first year after receiving the diagnosis of hand OA, which accounted for 8.1% (USD 68,826/USD 845,304) of the total costs.

Patients who saw additional providers and who were of younger age incurred higher costs and a greater likelihood of undergoing surgery; the latter was also greater in male patients. Use of medical services and associated costs vary widely among providers treating patients with hand OA. Initiatives addressing practice variation—increased use of decision aids, for example—merit additional study.

Level III, prognostic study. See the Instructions for Authors for a complete description of levels of evidence.