Centralization and the relationship between volume and outcome in knee arthroplasty procedures
ABSTRACT Centralization aims to reduce adverse patient outcomes by concentrating complex surgical procedures in specified hospitals.
This review assessed the efficacy of centralization for knee arthroplasty by examining the relationship between hospital and surgeon volume and patient outcomes.
The systematic review identified studies using multiple databases, including Medline and Embase. Two independent researchers ensured studies met the inclusion criteria. Morbidity, mortality, length of stay, financial outcomes and statistical rigour were examined. Correlations between volume and outcome were reported.
Twelve primary knee arthroplasty studies examined hospital volume, which was significantly associated with decreased morbidity (five of seven studies), mortality (two of five studies) and length of stay (two of three studies). Three primary knee arthroplasty studies examined surgeon volume, which was significantly associated with decreased morbidity (two of three studies), mortality (zero of two studies) and length of stay (one of one study). Two revision knee arthroplasty studies examined hospital volume. One study examined but did not test for significance between hospital volume and patient morbidity; both studies examined volume and patient mortality reporting inconclusive results; and one study reported no significant association between volume and length of stay. None of the revision knee arthroplasty studies examined surgeon volume.
Significant associations between increased hospital and surgeon volume and improved patient outcomes were reported. However, when these results were separated by arthroplasty type, the association appeared tenuous. Judgements regarding centralization of knee arthroplasty should be made with caution until further evidence is published.
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ABSTRACT: Many patients change hospitals for revision total joint arthroplasty (TJA). The implications of changing hospitals must be better understood to inform appropriate utilization strategies. (1) How frequently do patients change hospitals for revision TJA? (2) Which patient, community, and hospital characteristics are associated with changing hospitals? (3) Is there an increased complication risk after changing hospitals? We identified 17,018 patients who underwent primary TJA and subsequent same-joint revision in New York or California (1997-2005) from statewide databases. Medicare was the most common payer (56%) followed by private insurance (31%). We identified patients who changed hospitals for revision TJA and those who experienced in-hospital complications. Patient, community, and hospital characteristics were analyzed to determine predictors for changing hospitals for revision TJA and the effect of changing hospitals on subsequent complications. Thirty percent of patients changed hospitals for revision. Older patients were less likely to change hospitals (odds ratio [OR], 0.84; 95% confidence interval [CI], 0.73-0.96); no other patient characteristics were associated with changing hospitals. Patients who had index TJA at the highest-volume hospitals were less likely to change hospitals (OR, 0.52; 95% CI, 0.48-0.57). Overall, changing hospitals was associated with higher complication risk (OR, 1.19; 95% CI, 1.03-1.39). Changing to a lower-volume hospital (6% of patients undergoing revision TJA) was associated with a higher risk of complications (OR, 1.36; 95% CI, 1.05-1.74). A post hoc number needed-to-treat analysis indicates that 234 patients would need to be moved from a lower volume hospital to a higher volume hospital to avoid one overall complication event after revision TJA. Although the complication risk was higher if changing hospitals, this finding was sensitive to the type of change. Our findings build on the existing evidence of a volume-outcomes benefit for revision TJA by examining the effect of volume in view of potential patient migration. Level III, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.Clinical Orthopaedics and Related Research 03/2014; 472(7). DOI:10.1007/s11999-014-3515-z · 2.79 Impact Factor
Journal of the American College of Surgeons 03/2013; DOI:10.1016/j.jamcollsurg.2012.12.049 · 4.45 Impact Factor
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ABSTRACT: Revision rates following unicondylar knee replacement vary among reporting institutions. Revision rates from institutions involved in the design of these implants and independent single-center series are comparable with those following total knee replacement, suggesting that higher operative volumes and surgical enthusiasm improve revision outcomes. This registry-based cohort study involved the analysis of 23,400 medial cemented Oxford unicondylar knee replacements for the treatment of osteoarthritis. Total center and surgeon operative volumes were calculated over an eight-year time span since the inception of the registry (April 2003 to December 2010). The revision rate was calculated according to center volume and surgeon volume, each of which was grouped into five categories. The groups were compared with use of life tables, Kaplan-Meier plots, and Cox regression models that adjusted for variations in age, sex, and American Society of Anesthesiologists (ASA) grade among the groups. A total of 919 surgeons and a total of 366 centers performed at least one replacement, with the majority performing a small number of procedures. The revision rate for the centers with the lowest volume (fifty or fewer procedures over the eight-year study period) was 1.62 (95% confidence interval [CI], 1.42 to 1.82) revisions per 100 component years; this was significantly higher than the rate for the centers with the highest volume (more than 400 procedures), which was 1.16 (95% CI, 0.97 to 1.36) revisions per 100 component years. The five-year implant survival rate of 92.3% (95% CI, 91.2% to 93.3%) for the lowest-volume centers was significantly lower than the rate of 94.1% (95% CI, 93.0% to 95.2%) for the highest-volume centers. Similarly, the revision rate for the surgeons with the lowest volume (twenty-five or fewer procedures), 2.16 (95% CI, 1.91 to 2.41) revisions per 100 component years, was significantly higher than that for the surgeons with the highest volume (more than 200 procedures), 0.80 (95% CI, 0.62 to 0.98) revisions per 100 component years. The five-year survival rate of 90.1% (95% CI, 88.8% to 91.3%) for the lowest-volume surgeons was also significantly lower than the rate of 96.0% (95% CI, 95.0% to 97.0%) for the highest-volume surgeons. When center and surgeon volume were considered simultaneously, the hazard of revision was greater for lower-volume surgeons at lower-volume centers compared with higher-volume surgeons at higher-volume centers (hazard ratio = 1.87 [95% CI, 1.58 to 2.22], p < 0.001). High-volume centers and surgeons specializing in such procedures had superior results following unicondylar knee replacement compared with their low-volume counterparts. These results suggest that centers and surgeons should undertake a minimum of thirteen such procedures per year to achieve results comparable with the high-volume operators. Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.The Journal of Bone and Joint Surgery 04/2013; 95(8):702-9. DOI:10.2106/JBJS.L.00520 · 4.31 Impact Factor