Volume associations in total hip arthroplasty: a nationwide Taiwan population-based study

Effect of hospital volume on outcomes of total hip arthroplasty: a systematic review and meta-analysis

BACKGROUND

A shift in the healthcare system towards the centralization of common yet costly surgeries, such as total hip arthroplasty (THA), to high-volume centers of excellence, is an attempt to control the economic burden while simultaneously enhancing patient outcomes. The "volume-outcome" relationship suggests that hospitals performing more treatment of a given type exhibit better outcomes than hospitals performing fewer. This theory has surfaced as an important factor in determining patient outcomes following THA. We performed a systematic review with meta-analyses to review the available evidence on the impact of hospital volume on outcomes of THA.

MATERIALS AND METHODS

We conducted a review of PubMed (MEDLINE), OVID MEDLINE, Google Scholar, and Cochrane library of studies reporting the impact of hospital volume on THA. The studies were evaluated as per the inclusion and exclusion criteria. A total of 44 studies were included in the review. We accessed pooled data using random-effect meta-analysis.

RESULTS

Results of the meta-analyses show that low-volume hospitals were associated with a higher rate of surgical site infections (1.25 [1.01, 1.55]), longer length of stay (RR, 0.83[0.48-1.18]), increased cost of surgery (3.44, [2.57, 4.30]), 90-day complications (RR, 1.80[1.50-2.17]) and 30-day (RR, 2.33[1.27-4.28]), 90-day (RR, 1.26[1.05-1.51]), and 1-year mortality rates (RR, 2.26[1.32-3.88]) when compared to high-volume hospitals following THA. Except for two prospective studies, all were retrospective observational studies.

CONCLUSIONS

These findings demonstrate superior outcomes following THA in high-volume hospitals. Together with the reduced cost of the surgical procedure, fewer complications may contribute to saving considerable opportunity costs annually. However, a need to define objective volume-thresholds with stronger evidence would be required.

TRIAL REGISTRATION

PROSPERO CRD42019123776.

Optimal Hospital and Surgeon Volume Thresholds to Improve 30-Day Readmission Rates, Costs, and Length of Stay for Total Hip Replacement

BACKGROUND

Little is known about whether there are optimal hospital and surgeon volume thresholds to reduce readmission, costs, and length of stay (LOS) for total hip replacement (THR). Nationwide population-based data were applied to identify the optimal hospital and surgeon volume thresholds and to discover the effects of these volume thresholds on 30-day unplanned readmission, costs and LOS for THR.

METHODS

A total of 6367 patients identified through Taiwan's National Health Insurance Research Database received THR in 2012. Restricted cubic splines were used to identify the optimal hospital and surgeon volume needed to decrease the risk of 30-day unplanned readmission. Multilevel regression modeling and propensity score weighting were used to examine the impact of hospital and surgeon volume thresholds on 30-day unplanned readmission, costs, and LOS, after adjusting for patient, surgeon, and hospital characteristics.

RESULTS

The volume thresholds for hospitals and surgeons were 65 cases and 15 cases a year, respectively. The overall mean LOS was 7.3 ± 4.3 days. Patients who received THR from surgeons who did not reach the volume threshold had higher 30-day unplanned readmission rates, costs, and LOS than those who received THR from surgeons who reached the volume threshold.

CONCLUSION

This is the first study to identify the surgeon volume threshold that can reduce 30-day unplanned readmission rates, costs, and LOS for THR. However, the results from Taiwan may not be applicable to other parts of the world. Identifying the threshold could help patients, providers, and policymakers to make decisions regarding optimal delivery of THR.

Does Surgeon Volume Affect Outcomes Following Primary Total Hip Arthroplasty? A Systematic Review

BACKGROUND

Surgeon volume has been identified as an important factor impacting postoperative outcome in patients undergoing orthopedic surgeries. With an absence of a detailed systematic review, we sought to collate evidence on the impact of surgeon volume on postoperative outcomes in patients undergoing primary total hip arthroplasty.

METHODS

PubMed (MEDLINE) and Google Scholar databases were queried for articles using the following search criteria: ("Surgeon Volume" OR "Provider Volume" OR "Volume Outcome") AND ("THA" OR "Total hip replacement" OR "THR" OR "Total hip arthroplasty"). Studies investigating total hip arthroplasty being performed for malignancy or hip fractures were excluded from the review. Twenty-eight studies were included in the final review. All studies underwent a quality appraisal using the GRADE tool. The systematic review was performed in accordance with the PRISMA guidelines.

RESULTS

Increasing surgeon volume was associated with a shorter length of stay, lower costs, and lower dislocation rates. Studies showed a significant association between an increasing surgeon volume and higher odds of early-term and midterm survivorship, but not long-term survivorships. Although complications were reported and recorded differently in studies, there was a general trend toward a lower postoperative morbidity with regard to complications following surgeries by a high-volume surgeon.

CONCLUSION

This systematic review shows evidence of a trend toward better postoperative outcomes with high-volume surgeons. Future prospective studies are needed to better determine long-term postoperative outcomes such as survivorship before healthcare policies such as regionalization and/or equal-access healthcare systems can be considered.

Evidence-Based Thresholds for the Volume and Cost Relationship in Total Hip Arthroplasty: Outcomes and Economies of Scale

BACKGROUND

High-volume surgeons and hospital systems have been shown to deliver higher-value care in several studies. However, no evidence-based volume thresholds for cost currently exist in total hip arthroplasty (THA). The objective of this study was to establish meaningful thresholds in cost for surgeons and hospitals performing THA. A secondary objective was to analyze the market share of THAs for each surgeon and hospital stratifications.

METHODS

Using a database of 136,501 patients undergoing THA, we used stratum-specific likelihood ratio analysis of a receiver operating characteristic curve to generate volume thresholds based on costs for surgeons and hospitals. In addition, we examined the relative proportion of annual THA cases performed by each surgeon and hospital stratifications.

RESULTS

Stratum-specific likelihood ratio analysis of cost by annual surgeon THA volume produced stratifications at: 0-73 (low), 74-123 (medium), and 124 or more (high). Analysis by annual hospital THA volume produced stratifications at: 0-121 (low), 122-309 (medium), and 310 or more (high). Hospital costs decreased significantly (P < .05) in progressively higher volume stratifications. High-volume centers perform the largest proportion of THA cases (48.6%); however, low volume surgeons perform the greatest share of these cases (44.6%).

CONCLUSION

Our study establishes economies of scale in THA by demonstrating a direct relationship between volume and cost reduction. High-volume hospitals are performing the greatest proportion of THAs; however, low-volume surgeons perform the largest share of these cases, which highlights a potential area for enhanced value in the care of patients undergoing THA.

Evidence-Based Thresholds for the Volume and Length of Stay Relationship in Total Hip Arthroplasty: Outcomes and Economies of Scale

BACKGROUND

Several studies have indicated that high-volume surgeons and hospitals deliver higher value care. However, no evidence-based volume thresholds currently exist in total hip arthroplasty (THA). The primary objective of this study was to establish meaningful thresholds taking patient outcomes into consideration for surgeons and hospitals performing THA. A secondary objective was to examine the market share of THAs for each surgeon and hospital strata.

METHODS

Using 136,501 patients undergoing hip arthroplasty, we used stratum-specific likelihood ratio (SSLR) analysis of a receiver-operating characteristic curve to generate volume thresholds predictive of increased length of stay (LOS) for surgeons and hospitals. Additionally, we examined the relative proportion of annual THA cases performed by each surgeon and hospital strata established.

RESULTS

SSLR analysis of LOS by annual surgeon THA volume produced 3 strata: 0-69 (low), 70-121 (medium), and 121 or more (high). Analysis by annual hospital THA volume produced strata at: 0-120 (low), 121-357 (medium), and 358 or more (high). LOS decreased significantly (P < .05) in progressively higher volume categories. High-volume hospitals performed the majority of cases, whereas low-volume surgeons performed the majority of THAs.

CONCLUSION

Our study validates economies of scale in THA by demonstrating a direct relationship between volume and value for THA through risk-based volume stratification of surgeons and hospitals using SSLR analysis of receiver-operating characteristic curves to identify low-, medium-, and high-volume surgeons and hospitals. While the majority of primary THAs are performed at high-volume centers, low-volume surgeons are performing the majority of these cases, which may offer room for improvement in delivering value-based care.

Neuraxial anesthesia improves long-term survival after total joint replacement: a retrospective nationwide population-based study in Taiwan

INTRODUCTION

This study explored the effects of general (GA) and neuraxial (NA) anesthesia on the outcomes of primary total joint replacement (TJR) in terms of postoperative mortality, length of stay (LOS), and hospital treatment costs.

METHODS

From 1997 to 2010, this nationwide population-based study retrospectively evaluated 7,977 patients in Taiwan who underwent primary total hip or knee replacement. We generated two propensity-score-matched subgroups, each containing an equal number of patients who underwent TJR with either GA or NA.

RESULTS

Of the 7,977 patients, 2,990 (37.5%) underwent GA and 4,987 (62.5%) underwent NA. Propensity-score matching was used to create comparable GA and NA groups adjusted for age, sex, comorbidities, surgery type, hospital volume, and surgeon volume. Survival over the first three years following surgery was similar. The proportion of patients alive up to 14 years postoperatively for those undergoing NA was 58.2% (95% confidence interval [CI] 50.4 to 66.0), and for those undergoing GA it was 57.3% (95% CI 51.4 to 63.2). Neuraxial anesthesia was associated with lower median [interquartile range; IQR] hospital treatment cost ($4,079 [3,805-4,444] vs $4,113 [3,812-4,568]; P < 0.001) and shorter median [IQR] LOS (8 [7-10] days vs 8 [6-10] days, respectively; P = 0.024).

CONCLUSIONS

Our results support the use of NA for primary TJR. The improvements in hospital costs persist even when anesthesia costs are removed. The mechanism underlying the association between NA and long-term survival is unknown.