Is hip arthroscopy cost-effective for femoroacetabular impingement?

Abstract

Background: The impact of hip arthroscopy on health-related quality of life (HRQoL) among younger patients with symptomatic femoroacetabular impingement (FAI) is unknown, but with increasing recognition of the condition there is likely to be increasing demand for arthroscopy.

Questions/purposes: We describe an approach to determine the incremental cost-effectiveness of hip arthroscopy compared with observation in patients with FAI; we also identified variables that influence its cost-effectiveness.

Patients and methods: We constructed a Markov model including possible health states for 36-year-old patients with FAI using decision analysis software and compared two strategies: (1) observation and (2) hip arthroscopy, followed by THA with disease progression. We estimated the ratio of the incremental cost to the incremental benefit (reflected by HRQoL) of both strategies. We identified studies reporting Harris hip scores and complications after arthroscopy to estimate health state preferences and their probabilities. We performed sensitivity analyses on 30 input variables over a plausible range of estimates to determine the influence of uncertainty on the ICER with particular emphasis on the magnitude and duration of benefit.

Results: Among patients with FAI but no radiographic evidence of arthritis, the estimated ICER of hip arthroscopy was $21,700/QALY while the ICER for patients with preoperative arthritis was $79,500/QALY. Alteration of the natural history of arthritis by hip arthroscopy improved the ICER to $19,200/QALY and resulted in cost savings if THA was not performed until at least 16 years after arthroscopy.

Conclusions: Although limited by available data, our model suggests hip arthroscopy in patients with FAI without arthritis may result in a favorable ICER compared with other health interventions considered cost-effective. Further studies of hip arthroscopy are needed to determine the impact on quality of life, duration of symptomatic relief, and the effect on the need for subsequent THA.

Fig. 1

The incremental cost-effectiveness ratio (ICER) is the ratio of the net benefits and the net costs. QALY = quality-adjusted life-year.

Fig. 2

The flow-state diagram demonstrates the discrete health states considered after hip arthroscopy. Patients begin with either good hip function or a complication, which can be major or minor. After a specified duration, they progress to fair hip function. The dashed line denotes the two scenarios considered in which hip arthroscopy alters the progression of arthritis or provides symptomatic relief only. In the latter scenario, patients progress from good hip function after arthroscopy to poor hip function at the same rate as patients with fair hip function. In contrast, if hip arthroscopy alters the progression of arthritis, patients only progress to poor hip function after the progression from good to fair hip function. In the observation model, all patients begin in the “fair hip function” state.

Fig. 3A–C

The ICER is shown as a function of the duration of benefit for (A) symptomatic relief only with no baseline arthritis; (B) delay in progression of arthritis with no baseline arthritis; and (C) symptomatic relief with baseline arthritis. ICER = incremental cost-effectiveness ratio; QALY = quality-adjusted life-year.

Fig. 4

The incremental cost-effectiveness ratio as a function of the cost of hip arthroscopy is shown in a one-way sensitivity analysis. ICER = incremental cost-effectiveness ratio; QALY = quality-adjusted life-year.

Fig. 5

The incremental cost-effectiveness ratio as a function of the utility after hip arthroscopy is shown in a one-way sensitivity analysis. ICER = incremental cost-effectiveness ratio; QALY = quality-adjusted life-year.

Fig. 6

Two-way sensitivity analysis indicates the preferred strategy as a function of both the magnitude and duration of benefit using a willingness to pay of $50,000/quality-adjusted life-year.

Fig. 7A–B

Tornado diagrams show the range of incremental cost-effectiveness ratios resulting from one-way sensitivity analysis of multiple variables on the same scale for the case of (A) no arthritis at baseline and (B) arthritis at baseline. Variables that resulted in a range of less than $1000/quality-adjusted life-year were not included. ICER = incremental cost-effectiveness ratio; QALY = quality-adjusted life-year.

Fig. 8A–B

The diagrams show cost-effectiveness acceptability curves for patients with a low rate of progression to arthritis (A) and a high rate of progression to arthritis (B).