The volume-outcome relationship for hip fractures: a systematic review and meta-analysis of 2,023,469 patients

Increased 90-Day Readmissions and Complications Following Hip Arthroscopy in Centers With Low Surgical Volume in New York State

PURPOSE

To (1) classify surgical centers in New York State by volume of hip arthroscopies performed, (2) calculate rates of readmissions and complications by center volume, and (3) identify socioeconomic predictive factors for readmissions and complications following hip arthroscopy.

METHODS

Patients who underwent hip arthroscopy at New York State health care facilities from 2010 to 2020 were retrospectively identified using the New York Statewide Planning and Research Cooperative System (SPARCS) database. Hip arthroscopic procedures were identified using the following Current Procedural Terminology codes. Surgical center volumes were classified into 3 categories: low (<85th percentile), medium (85th-95th percentile), and high (>95th percentile). Incidence of readmissions and complications within 90 days was abstracted from SPARCS. Neighborhood socioeconomic status was quantified using the U.S. Area Deprivation Index. Multivariable logistic regression was used to determine whether center volume and other socioeconomic variables were independent predictors of outcomes.

RESULTS

In total, 50,252 patients who underwent hip arthroscopy were identified in SPARCS from 2010 to 2020. Of these patients, 13,861 (27.6%) underwent surgery at low-volume centers, 11,757 (23.4%) at medium-volume centers, and 24,634 (49.0%) at high-volume centers. Minorities, publicly insured patients, and patients from lower socioeconomic status neighborhoods made up a larger proportion of cases seen by low-volume centers versus high-volume centers (P < .001). Patients in the low-volume group experienced significantly greater 90-day rates of readmissions (P < .001) and all-cause complications (P < .001) than the other groups. Furthermore, high-volume centers were independently associated with lower odds of readmission (odds ratio 0.57, P < .001) and all-cause complications (odds ratio 0.73, P < .001) versus low-volume centers.

CONCLUSIONS

Low-volume surgical centers are associated with increased readmission and complication rates following hip arthroscopy, independent of other socioeconomic factors such as age, sex, race, insurance status, and neighborhood socioeconomic status.

LEVEL OF EVIDENCE

Level III, retrospective comparative prognostic trial.

In France, distance from hospital and health care structure impact on outcome after arthroplasty of the hip for proximal fractures of the femur

BACKGROUND

Hip arthroplasty is a frequently performed procedure in orthopedic surgery, carried out in almost all health structures for two main issues: fracture and coxarthrosis. Even if volume-outcome relationship appeared associated in many surgeries recently, data provided are not sufficient to set surgical thresholds neither than closing down low-volumes centers.

QUESTION

With this study, we wanted to identify surgical, health care-related and territorial factors influencing patient' mortality and readmission after a HA for a femoral fracture in 2018 in France.

PATIENTS AND METHODS

Data were anonymously collected from French nationwide administrative databases. All patients who underwent a hip arthroplasty for a femoral fracture through 2018 were included. Patient outcome was 90-day mortality and 90-day readmission rate after surgery.

RESULTS

Of the 36,252 patients that underwent a HA for fracture in France in 2018, 0.7% died within 90-day year and 1.2% were readmitted. Male and Charlson comorbidity index were associated with a higher 90-day mortality and readmission rate in multivariate analysis. High volume was associated with a lower mortality rate. Neither time of travel nor distance upon health facility were associated with mortality nor with readmission rate in the analysis.

CONCLUSION

Even if volume appears to be associated with lower mortality rate even for longer distance and time of travel, the persistence of exogenous factors not documented in the French databases suggests that regionalization of hip arthroplasty should be organized with caution.

CLINICAL RELEVANCE

As volume-outcome relationship must be interpreted with caution, policy makers should not regionalize such surgery without further investigation.

The Effect of Surgeon and Hospital Volume on Morbidity and Mortality After Femoral Shaft Fractures

OBJECTIVES

The aim of this study was to characterize the case volume dependence of both facilities and surgeons on morbidity and mortality after femoral shaft fracture (FSF) fixation.

METHODS

Adults who had an open or closed FSF between 2011 and 2015 were identified in the New York Statewide Planning and Research Cooperative System database. Claims were identified by International Classification of Disease-9, Clinical Modification diagnostic codes for a closed or open FSF and International Classification of Disease-9, Clinical Modification procedure codes for FSF fixation. Readmission, in-hospital mortality, and other adverse events were compared across surgeon and facility volumes using multivariable Cox proportional hazards regression, controlling for patient demographic and clinical factors. Surgeon and facility volumes were compared between the lowest and highest 20% to represent low-volume and high-volume surgeons/facilities.

RESULTS

Of 4,613 FSF patients identified, 2,824 patients were treated at a high or low-volume facility or by a high or low-volume surgeon. Most of the examined complications including readmission and in-hospital mortality showed no statistically significant differences. Low-volume facilities had a higher 1-month rate of pneumonia. Low-volume surgeons had a lower 3-month rate of pulmonary embolism.

CONCLUSION

There is minimal difference in outcomes in relation to facility or surgeon case volume for FSF fixation. As a staple of orthopaedic trauma care, FSF fixation is a procedure that may not require specialized orthopaedic traumatologists at high-volume facilities.

Is hospital volume related to quality of hip fracture care? Analysis of 43,538 patients and 68 hospitals from the Dutch Hip Fracture Audit

PURPOSE

Evidence for a hospital volume-outcome relationship in hip fracture surgery is inconclusive. This study aimed to analyze the association between hospital volume as a continuous parameter and several processes and outcomes of hip fracture care.

METHODS

Adult patients registered in the nationwide Dutch Hip Fracture Audit (DHFA) between 2018 and 2020 were included. The association between annual hospital volume and turnaround times (time on the emergency ward, surgery < 48 h and length of stay), orthogeriatric co-treatment and case-mix adjusted in-hospital and 30 days mortality was evaluated with generalized linear mixed models with random effects for hospital and treatment year. We used a fifth-degree polynomial to allow for nonlinear effects of hospital volume. P-values were adjusted for multiple comparisons using the Bonferoni method.

RESULTS

In total, 43,258 patients from 68 hospitals were included. The median annual hospital volume was 202 patients [range 1-546]. Baseline characteristics did not differ with hospital volume. Provision of orthogeriatric co-treatment improved with higher volumes but decreased at > 367 patients per year (p < 0.01). Hospital volume was not significantly associated with mortality outcomes. No evident clinical relation between hospital volume and turnaround times was found.

CONCLUSION

This is the first study analyzing the effect of hospital volume on hip fracture care, treating volume as a continuous parameter. Mortality and turnaround times showed no clinically relevant association with hospital volume. The provision of orthogeriatric co-treatment, however, increased with increasing volumes up to 367 patients per year, but decreased above this threshold. Future research on the effect of volume on complications and functional outcomes is indicated.

The case for decreased surgeon-reported complications due to surgical volume and fellowship status in the treatment of geriatric hip fracture: An analysis of the ABOS database

Introduction

American orthopaedists are increasingly seeking fellowship sub-specialization. One proposed benefit of fellowship training is decrease in complications, however, few studies have investigated the rates of medical and surgical complications for hip fracture patients between orthopedists from different fellowship backgrounds. This study aims to investigate the effect of fellowship training and case volume on medical and surgical outcomes of patient following hip fracture surgical intervention.

Methods

1999–2016 American Board of Orthopedic Surgery (ABOS) Part II Examination Case List data were used to assess patients treated by trauma or adult reconstruction fellowship-trained orthopedists versus all-other orthopaedists. Rates of surgeon-reported medical and surgical adverse events were compared between the three surgeon cohorts. Using binary multivariate logistic regression to control of demographic factors, independent factors were evaluated for their effect on surgical complications.

Results

Data from 73,427 patients were assessed. An increasing number of hip fractures are being treated by trauma fellowship trained surgeons (9.43% in 1999–2004 to 60.92% in 2011–2016). In multivariate analysis, there was no significant difference in type of fellowship, however, surgeons with increased case volume saw significantly decreased odds of complications (16–30 cases: OR = 0.91; 95% CI: 0.85–0.97; p = 0.003; 31+ cases: OR = 0.68; 95% CI: 0.61–0.76; p<0.001). Femoral neck hip fractures were associated with increased odds of surgical complications.

Discussion

Despite minor differences in incidence of surgical complications between different fellowship trained orthopaedists, there is no major difference in overall risk of surgical complications for hip fracture patients based on fellowship status of early orthopaedic surgeons. However, case volume does significantly decrease the risk of surgical complications among these patients and may stand as a proxy for fellowship training. Fellows required to take hip fracture call as part of their training regardless of fellowship status exhibited decreased complication risk for hip fracture patients, thus highlighting the importance of additional training.

The influence of hospital-level variables on hip fracture outcomes

AIMS

The aim of this study was to determine the impact of hospital-level service characteristics on hip fracture outcomes and quality of care processes measures.

METHODS

This was a retrospective analysis of publicly available audit data obtained from the National Hip Fracture Database (NHFD) 2018 benchmark summary and Facilities Survey. Data extraction was performed using a dedicated proforma to identify relevant hospital-level care process and outcome variables for inclusion. The primary outcome measure was adjusted 30-day mortality rate. A random forest-based multivariate imputation by chained equation (MICE) algorithm was used for missing value imputation. Univariable analysis for each hospital level factor was performed using a combination of Tobit regression, Siegal non-parametric linear regression, and Mann-Whitney U test analyses, dependent on the data type. In all analyses, a p-value < 0.05 denoted statistical significance.

RESULTS

Analyses included 176 hospitals, with a median of 366 hip fracture cases per year (interquartile range (IQR) 280 to 457). Aggregated data from 66,578 patients were included. The only identified hospital-level variable associated with the primary outcome of 30-day mortality was hip fracture trial involvement (no trial involvement: median 6.3%; trial involvement: median 5.7%; p = 0.039). Significant key associations were also identified between prompt surgery and presence of dedicated hip fracture sessions; reduced acute length of stay and both a higher number of hip fracture cases per year and more dedicated hip fracture operating lists; Best Practice Tariff attainment and greater number of hip fracture cases per year, more dedicated hip fracture operating lists, presence of a dedicated hip fracture ward, and hip fracture trial involvement.

CONCLUSION

Exploratory analyses have identified that improved outcomes in hip fracture may be associated with hospital-level service characteristics, such as hip fracture research trial involvement, larger hip fracture volumes, and the use of theatre lists dedicated to hip fracture surgery. Further research using patient level data is warranted to corroborate these findings. Cite this article: Bone Joint J 2021;103-B(10):1627-1632.

Short-term outcome of isolated lateral malleolar fracture treatment is independent of hospital trauma volume or teaching status: a nationwide retrospective cohort study

Introduction

In light of current discussions about centralisation and teaching in medicine, we wanted to investigate the differences in in-hospital outcomes after surgical treatment of isolated ankle fractures, taking into account high-volume centres (HVCs) and low-volume centres (LVCs) and teaching procedures.

Methods

A retrospective analysis of malleolar fractures recorded in a National Quality Assurance Database (AQC) from the period 01-01-1998 to 31-12-2018 was carried out. Inclusion criteria were isolated, and operatively treated lateral malleolar fractures (ICD-10 Code S82.6 and corresponding procedure codes). Variables were sought in bivariate and multivariate analyses. A total of 6760 cases were included. By dividing the total cases arbitrarily in half, 12 HVCs (n = 3327, 49%) and 56 LVCs (n = 3433, 51%) were identified.

Results

Patients in HVCs were younger (48 vs. 50 years old), had more comorbidities (26% vs. 19%) and had more open fractures (0.48% vs. 0.15%). Open reduction and internal fixation was the most common operative treatment at HVCs and LVCs (95% vs. 98%). A more frequent use of external fixation (2.5% vs. 0.55%) was reported at HVCs. There was no difference in mortality between treatment at HVCs and LVCs. A longer hospitalisation of 7.2 ± 5 days at HVCs vs. 6.3 ± 4.8 days at LVCs was observed. In addition, a higher rate of complications of 3.2% was found at HVCs compared to 1.9% at LVCs. The frequency of teaching operations was significantly higher at HVCs (30% vs. 26%). Teaching status had no influence on mortality or complications but was associated with a prolonged length of stay and operating time.

Conclusion

We found significant differences between HVCs and LVCs in terms of in-hospital outcomes for ankle fractures. These differences could be explained due to a more severely ill patient population and more complex (also open) fracture patterns with resulting use of external fixation and longer duration of surgery. However, structural and organisational differences, such as an extended preoperative stays at HVCs and a higher teaching rate, were also apparent. No difference in mortality could be detected.

Trends in Comorbidities and Complications Among Patients Undergoing Hip Fracture Repair

BACKGROUND

Hip fracture patients represent various perioperative challenges related to their significant comorbidity burden and the high incidence of morbidity and mortality. As population trend data remain rare, we aimed to investigate nationwide trends in the United States in patient demographics and outcomes in patients after hip fracture repair surgery.

METHODS

After Institutional Review Board (IRB) approval (IRB#2012-050), data covering hip fracture repair surgeries were extracted from the Premier Healthcare Database (2006-2016). Patient demographics, comorbidities, and complications, as well as anesthesia and surgical details, were analyzed over time. Cochran-Armitage trend tests and simple linear regression assessed significance of (linear) trends.

RESULTS

Among N = 507,274 hip fracture cases, we observed significant increases in the incidence in preexisting comorbid conditions, particularly the proportion of patients with >3 comorbid conditions (33.9% to 43.4%, respectively; P < .0001). The greatest increase for individual comorbidities was seen for sleep apnea, drug abuse, weight loss, and obesity. Regarding complications, increased rates over time were seen for acute renal failure (from 6.9 to 11.1 per 1000 inpatient days; P < .0001), while significant decreasing trends for mortality, pneumonia, hemorrhage/hematoma, and acute myocardial infarction were recorded. In addition, decreasing trends were observed for the use of neuraxial anesthesia either used as sole anesthetic or combined with general anesthesia (7.3% to 3.6% and 6.3% to 3.4%, respectively; P < .0001). Significantly more patients (31.9% vs 41.3%; P < .0001) were operated on in small rather than medium- and large-sized hospitals.

CONCLUSIONS

From 2006 to 2016, the overall comorbidity burden increased among patients undergoing hip fracture repair surgery. Throughout this same time period, incidence of postoperative complications either remained constant or declined with the only significant increase observed in acute renal failure. Moreover, use of regional anesthesia decreased over time. This more comorbid patient population represents an increasing burden on the health care system; however, existing preventative measures appear to be effective in minimizing complication rates. Although, given the proposed benefits of regional anesthesia, decreased utilization may be of concern.

Effect of referral systems on costs and outcomes after hip fracture surgery in Taiwan

OBJECTIVE

To explore the economic burdens of hip fracture surgery in patients referred to lower-level medical institutions and to evaluate how referral systems affect costs and outcomes of hip fracture surgery.

DESIGN

A nationwide population-based retrospective cohort study.

SETTING

All hospitals in Taiwan.

PARTICIPANTS

A total of 7500 patients who had received hip fracture surgery (International Classification of Disease, 9th Revision, Clinical Modification (ICD-9-CM) diagnostic codes 820.0 ∼ 820.9 and procedure codes 79.15, 79.35, 81.52, 81.53) performed in 1997 to 2013.

MAIN OUTCOME MEASURES

Total costs including outpatient costs, inpatient costs and total medical costs and medical outcomes including 30-day readmission, 90-day readmission, infection, dislocation, revision and mortality.

RESULTS

The patients were referred to a lower medical institution after hip fracture surgery (downward referral group) and 3034 patients continued treatment at the same medical institution (non-referral group). Demographic characteristics, clinical characteristics and institutional characteristics were significantly associated with postoperative costs and outcomes (P < 0.05). On average, the annual healthcare cost was New Taiwan Dollars (NT$)2262 per patient lower in the downward referral group compared with the non-referral group. The annual economic burdens of the downward referral group approximated NT$241 million (2019 exchange rate, NT$30.5 = US$1).

CONCLUSIONS

Postoperative costs and outcomes of hip fracture surgery are related not only to demographic and clinical characteristics, but also to institutional characteristics. The advantages of downward referral after hip fracture surgery can save huge medical costs and provide a useful reference for healthcare authorities when drafting policies for the referral system.

Clinical management of hip fractures in elderly patients with dementia and postoperative 30-day mortality: A population-based cohort study

OBJECTIVES

Patients with dementia have an increased 30-day mortality after hip fracture. We investigated clinical management including time to surgery, out-of-hours admission and surgery, surgery on weekends, surgery volume per ward, and anesthesia technique for this excess mortality risk.

METHOD

This register- and population-based study comprised 12,309 older adults (age 70+) admitted to hospital for a first-time hip fracture in 2013-2014, of whom 11,318 underwent hip fracture surgery. Cox proportional hazards regression models were applied for the analysis.

RESULTS

The overall postoperative 30-day mortality was 11.4%. Patients with dementia had a 1.5 times increased mortality risk than those without (HR = 1.50 [95% CI 1.31-1.72]). We observed no time-to-surgery difference by patient dementia status; additionally, the excess mortality risk in patients with dementia could not be explained by the clinical management factors we examined.

CONCLUSIONS

Increased mortality in patients with dementia could not be explained by the measured preoperative clinical management. Suboptimal handling of postoperative complication and rehabilitation are to be investigated for their role in the witnessed increased mortality for patients with dementia.

Do small hospitals have lower quality? Evidence from the English NHS

We investigate the extent to which small hospitals are associated with lower quality. We first take a patient perspective, and test if, controlling for casemix, patients admitted to small hospitals receive lower quality than those admitted to larger hospitals. We then investigate if differences in quality between large and small hospitals can be explained by hospital characteristics such as hospital type and staffing. We use a range of quality measures including hospital mortality rates (overall and for specific conditions), hospital acquired infection rates, waiting times for emergency patients, and patient perceptions of the care they receive. We find that small hospitals, with fewer than 400 beds, are generally not associated with lower quality before or after controlling for hospital characteristics. The only exception is heart attack mortality, which is generally higher in small hospitals.

The association between hospital case volume and in-hospital and one-year mortality after hip fracture surgery

Aims

Hospital case volume is shown to be associated with postoperative outcomes in various types of surgery. However, conflicting results of volume-outcome relationship have been reported in hip fracture surgery. This retrospective cohort study aimed to evaluate the association between hospital case volume and postoperative outcomes in patients who had hip fracture surgery. We hypothesized that higher case volume would be associated with lower risk of in-hospital and one-year mortality after hip fracture surgery.

Methods

Data for all patients who underwent surgery for hip fracture from January 2008 to December 2016 were extracted from the Korean National Healthcare Insurance Service database. According to mean annual case volume of surgery for hip fracture, hospitals were classified into very low (< 30 cases/year), low (30 to 50 cases/year), intermediate (50 to 100 cases/year), high (100 to 150 cases/year), or very high (> 150 cases/year) groups. The association between hospital case volume and in-hospital mortality or one-year mortality was assessed using the logistic regression model to adjust for age, sex, type of fracture, type of anaesthesia, transfusion, comorbidities, and year of surgery.

Results

Between January 2008 and December 2016, 269,535 patients underwent hip fracture surgery in 1,567 hospitals in Korea. Compared to hospitals with very high volume, in-hospital mortality rates were significantly higher in those with high volume (odds ratio (OR) 1.10, 95% confidence interval ((CI) 1.02 to 1.17, p = 0.011), low volume (OR 1.22, 95% CI 1.14 to 1.32, p < 0.001), and very low volume (OR 1.25, 95% CI 1.16 to 1.34, p < 0.001). Similarly, hospitals with lower case volume showed higher one-year mortality rates compared to hospitals with very high case volume (low volume group, OR 1.15, 95% CI 1.11 to 1.19, p < 0.001; very low volume group, OR 1.10, 95% CI 1.07 to 1.14, p < 0.001).

Conclusion

Higher hospital case volume of hip fracture surgery was associated with lower in-hospital mortality and one-year mortality in a dose-response fashion. Cite this article: Bone Joint J 2020;102-B(10):1384–1391.

Arthroplasty Surgeons Do Not Improve Acute Outcomes for Patients With Hip Fracture Relative to Other Subspecialists

As bundled reimbursement models continue to evolve, there is a continued effort to increase the value of care for patients undergoing arthroplasty. The authors sought to evaluate the effect of surgeon specialization (arthroplasty vs non-arthroplasty) on acute outcomes for patients with hip fracture who underwent total hip arthroplasty (THA), in an effort to determine whether the value of care can be improved by surgeons specializing in these procedures. They performed a multicenter retrospective cohort study of patients who had hip fracture and were treated with THA between June 2013 and February 2018 at 2 academic institutions that were involved in bundled reimbursement initiatives. Patients were stratified based on the subspecialty training of the operative surgeon (fellowship-trained adult reconstruction vs other orthopedic sub-specialty), and 90-day readmissions, length of stay, and discharge disposition were compared between groups. A total of 291 patients were included in the final cohort, with 120 (41.2%) undergoing surgery performed by a fellowship-trained adult reconstruction surgeon. No significant difference was found in age, sex, race, or American Society of Anesthesiologists score between the 2 groups. In addition, no significant difference was found in length of stay, discharge to a facility, or 90-day readmissions on univariable or multivariable analysis when adjusted for age, sex, body mass index, and American Society of Anesthesiologists score. This study showed that the acute outcomes used to assess the value of care for patients undergoing THA were not significantly different when the surgery was performed by an adult reconstruction specialist compared with other orthopedic surgeons at 2 high-volume academic centers with perioperative care pathways. Alternative modalities to significantly improve acute postoperative outcomes in a bundled reimbursement model must be investigated. [Orthopedics. 2020;43(5):e442-e446.].

Annual case volume is a risk factor for 30-day unplanned readmission after open reduction and internal fixation of acetabular fractures

BACKGROUND

Surgical fixation of acetabular fractures is technically challenging, and quality of reduction directly correlates to patient outcomes. Considering the difficulty of open reduction and internal fixation (ORIF), increased case volumes may improve patient outcomes. No studies have investigated case volume as a risk factor for readmission after acetabular fracture ORIF. The present study sought to answer the question of whether annual case volume is a risk factor for 30-day unplanned readmission after acetabular fracture ORIF, if there is an identifiable threshold number of cases most predictive of a readmission, and if differences exist between reasons for readmission between high and low-volume centers.

HYPOTHESIS

Institutions with a lower annual case volume will have a higher incidence of 30-day unplanned readmissions.

MATERIALS AND METHODS

The national readmissions database (NRD) was queried for acetabular fractures that underwent ORIF during 2016. Comorbid conditions were summed, and annual hospital case volume was identified. A receiver operating characteristic (ROC) curve was generated and the Youden index identified threshold case volume most predictive of a 30-day readmission. A multivariable logistic regression was performed with 30-day readmission as the dependent variable and case volume below the threshold an independent variable.

RESULTS

A total of 3,407 cases were included with a median age of 43. The 30-day readmission for this cohort was 6.5% (220/3407). ROC curve analysis identified 22 annual cases as the threshold value most predictive of 30-day readmission. Multivariable logistic regression identified age (Odds Ratio (OR)=1.01, p=0.005), number of comorbidities (OR=1.35, p<0.0001), and ≤22 cases (OR=1.50, p=0.006) as statistically significant risk factors for 30-day readmission. The most common reason for readmission at both high and low-volume centers was surgical site infection.

DISCUSSION

Annual case volume is a statistically significant predictor of 30-day readmission after acetabular fracture ORIF. Performing ≤22 acetabular ORIFs places patients at greater risk for a readmission. Patients at low-volume centers may be predisposed to readmission, and it is paramount to optimize patients prior to discharge, and have appropriate surgeon and hospital resources to treat these complex injuries.

LEVEL OF EVIDENCE

III, Cross-sectional study.