The impact of new hospital orthopaedic surgery programs on total joint arthroplasty utilization

Abstract

Background: Utilization of arthroplasty is increasing, but there are little data exploring the causes of this increase. The objective of this study was to examine the relationship between new programs for arthroplasty of the lower extremity joints and the utilization of arthroplasty.

Methods: We identified twenty-four markets (hospital referral regions) that experienced the entry of new physician-owned specialty hospitals, using 1991 to 2005 Medicare data. We matched each market with a new specialty hospital to two different control markets (one market with a new arthroplasty program in a general hospital and one market without a new arthroplasty program), using a propensity score that accounted for market supply and demand for orthopaedic surgery and the regulatory environment. We compared the utilization of arthroplasty of the lower extremity joints (total hip arthroplasty and total knee arthroplasty) in each group of markets over a five-year window, extending from two years before to three years after the entry of new orthopaedic surgery programs.

Results: The twenty-four markets with new specialty orthopaedic hospitals had higher utilization of arthroplasty at baseline (10.9 arthroplasties per 1000 Medicare beneficiaries per year) and follow-up (12.7 per 1000 beneficiaries) compared with the twenty-four markets with new arthroplasty programs in general hospitals (9.7 and 11.4, respectively) and the twenty-four markets with no new programs (9.9 and 11.3), although the differences were not significant (p > 0.05). Growth in the utilization of arthroplasty was similar in markets with new specialty hospitals before (an increase of 0.63 procedure per 1000 beneficiaries per year) and after the entry of new specialty hospitals (an increase of 0.39) compared with markets with new surgery programs in general hospitals (an increase of 0.24 before and 0.43 after) and markets with no new programs (an increase of 0.38 before and 0.33 after the entry of new specialty hospitals) (p > 0.05 for all comparisons).

Conclusions: The utilization of arthroplasty is increasing at similar rates in markets with and without new arthroplasty programs.

Fig. 1

Standardized procedural utilization rates per 1000 Medicare enrollees by year in markets with new specialty hospitals, markets with new orthopaedic programs or hospitals, and markets with no new orthopaedic program or hospital.

Fig. 2

Changes in total joint arthroplasty utilization per 1000 Medicare enrollees in successive years in markets with new specialty hospitals, markets with new orthopaedic programs or hospitals, and markets with no new orthopaedic program or hospital (higher values correspond to higher year-to-year growth in utilization).

Fig. 3

Utilization of total joint arthroplasty among markets with high-volume specialty hospitals.