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Original Article| Volume 4, ISSUE 5, e1683-e1691, October 2022

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Alcohol Abuse, Morbid Obesity, Depression, Congestive Heart Failure, and Chronic Pulmonary Disease are Risk Factors for 90-Day Readmission After Arthroscopic Rotator Cuff Repair

Open AccessPublished:August 28, 2022DOI:https://doi.org/10.1016/j.asmr.2022.06.015

Purpose

The purpose of this study was to report the rate and causes of 90-day readmissions after arthroscopic rotator cuff repair.

Methods

A retrospective query from January 2005 to March 2014 was performed using a nationwide administrative claims registry. Patients and complications were identified using International Classification of Disease, Ninth Revision (ICD-9) and Current Procedural Terminology (CPT) codes. Patients who underwent arthroscopic rotator cuff repair (RCR) and were readmitted within 90 days after their index procedure were identified. Patients not readmitted represented controls. Patients readmitted were stratified into separate cohorts depending on the primary cause of readmission, which included cardiac, endocrine, hematological, infectious, gastrointestinal, musculoskeletal (MSK), neoplastic, neurological or psychiatric, pulmonary, and renal. Risk factors assessed were comorbidities comprising the Elixhauser-Comorbidity Index (ECI). Primary outcomes analyzed and compared included cause for readmission, patient demographics, risk factors, in-hospital length of stay (LOS), and costs. Pearson’s chi-square was used to compare patient demographics, and multivariate binomial logistic regression was used to calculate odds ratios (OR) on patient-related risk factors for 90-day readmissions.

Results

10,425 readmitted patients and 301,625 control patients were identified, representing a 90-day readmission rate of 3.5%. The causes of readmissions were primarily related to infectious diseases (15%), MSK (15%), and cardiac (14%) complications. The most common MSK readmissions were osteoarthrosis of the leg or shoulder (24.8%) and spinal spondylosis (8.4%). Multivariate binomial logistic regression analyses demonstrated patients with alcohol abuse (OR, 1.42; P < .0001), morbid obesity (OR, 1.38; P < .0001), depression (OR, 1.35; P < .0001), congestive heart failure (OR, 1.34; P < 0.0001), and chronic pulmonary disease (OR, 1.28; P < .0001) were at the greatest risk of readmissions after RCR.

Conclusions

Significant differences exist among patients readmitted, and those patients who do not require hospital readmission within 90 days following arthroscopic rotator cuff repairs. Readmissions are associated with significant patient comorbidities and were primarily related to medically based complications.

Level of Evidence

Level III, prognostic, retrospective cohort study.

Introduction

With improvements in technology and broader indications for shoulder arthroscopy, the use of arthroscopy for rotator cuff repair has continued to steadily increase over the past decade and a half.
  • Day M.A.
  • Westermann R.W.
  • Bedard N.A.
  • Glass N.A.
  • Wolf B.R.
Trends associated with open versus arthroscopic rotator cuff repair.
  • Zhang A.L.
  • Montgomery S.R.
  • Ngo S.S.
  • Hame S.L.
  • Wang J.C.
  • Gamradt S.C.
Analysis of rotator cuff repair trends in a large private insurance population.
  • Mauro C.S.
  • Jordan S.S.
  • Irrgang J.J.
  • Harner C.D.
Practice patterns for subacromial decompression and rotator cuff repair: An analysis of the American Board of Orthopaedic Surgery database.
This trend is anticipated to continue as the proportion of rotator cuff repairs done arthroscopically among orthopedic surgeons taking Part II of the American Board of Orthopaedic Surgery (ABOS) certification examination was recently reported to be 90%.
  • Kelly B.C.
  • Constantinescu D.S.
  • Vap A.R.
Arthroscopic and open or mini-open rotator cuff repair trends and complication rates among American Board of Orthopaedic Surgeons Part II examinees (2007-2017).
Additionally, the rise in health care costs and passage of the Affordable Care Act has led to cost containment and quality-improvement initiatives to be implemented by the Centers of Medicare & Medicaid Services (CMS). This has empowered private insurers to do so as well
  • Clemens J.
  • Gottlieb J.D.
In the shadow of a giant medicare’s influence on private physician payments.
and led to the exploration of alternative reimbursement models such as bundled-payment systems, which incentivize hospitals to be cost-efficient. Two specific areas that have been identified to decrease costs are reducing postoperative readmissions and length of hospital stay.
  • Rana A.J.
  • Bozic K.J.
Bundled payments in orthopaedics.
With rotator cuff repairs making up the largest proportion of all arthroscopic cases,
  • Hill J.R.
  • McKnight B.
  • Pannell W.C.
  • et al.
Risk factors for 30-day readmission following shoulder arthroscopy.
it is imperative for surgeons to understand the risk factors that may lead to readmission following this procedure.
Several studies have reported complication and readmission rates after shoulder arthroscopy to be approximately 0.86-1%.
  • Hill J.R.
  • McKnight B.
  • Pannell W.C.
  • et al.
Risk factors for 30-day readmission following shoulder arthroscopy.
  • Westermann R.W.
  • Pugely A.J.
  • Ries Z.
  • et al.
Causes and predictors of 30-day readmission after shoulder and knee arthroscopy: An analysis of 15,167 cases.
  • Martin C.T.
  • Gao Y.
  • Pugely A.J.
  • Wolf B.R.
30-day morbidity and mortality after elective shoulder arthroscopy: A review of 9410 cases.
  • Shields E.
  • Thirukumaran C.
  • Thorsness R.
  • Noyes K.
  • Voloshin I.
An analysis of adult patient risk factors and complications within 30 days after arthroscopic shoulder surgery.
A single study that specifically examined arthroscopic rotator cuff repairs reported a complication rate of 0.70%.
  • Heyer J.H.
  • Kuang X.
  • Amdur R.L.
  • Pandarinath R.
Identifiable risk factors for thirty-day complications following arthroscopic rotator cuff repair.
However, all these studies used the National Surgical Quality Improvement Program (NSQIP) database, which does not contain complications that occur beyond 30 days and cases performed at independent surgery centers, an increasing source of rotator cuff repair cases. In addition, reasons for readmission were notably lacking from the NSQIP database and listed as a potential limitation in these studies.
  • Hill J.R.
  • McKnight B.
  • Pannell W.C.
  • et al.
Risk factors for 30-day readmission following shoulder arthroscopy.
,
  • Westermann R.W.
  • Pugely A.J.
  • Ries Z.
  • et al.
Causes and predictors of 30-day readmission after shoulder and knee arthroscopy: An analysis of 15,167 cases.
,
  • Kosinski L.R.
  • Gil J.A.
  • Durand W.M.
  • DeFroda S.F.
  • Owens B.D.
  • Daniels A.H.
30-Day readmission following outpatient rotator cuff repair: An analysis of 18,061 cases.
Therefore, despite favorable outcomes following arthroscopic rotator cuff repair (RCR), an adequate characterization of 90-day readmissions following the procedure has not been well documented. The purpose of this study was to report the rate and causes of 90-day readmissions after arthroscopic rotator cuff repair. Our hypothesis was that 90-day readmission rates would be greater than previously reported 30-day readmissions rates, and patients with greater comorbidities were more likely to be readmitted following arthroscopic rotator cuff repair.

Methods

All work was performed at the Holy Cross Hospital and Holy Cross Orthopedic Institute. A retrospective query from January 1, 2005, to March 31, 2014, was performed using a nationwide administrative claims registry comprising a Medicare population (PearlDiver, Pearl-Diver Technologies, Fort Wayne, IN). Patients undergoing arthroscopic rotator cuff repair and any postoperative complications were identified using Current Procedural Terminology (CPT) codes and International Classification of Disease, Ninth Revision (ICD-9). Patients readmitted within 90 days after the index procedure were identified and served as the study cohort. Patients not readmitted within 90 days represented controls. Outcomes analyzed were reason for readmission, patient demographics, risk factors for readmission, in-hospital LOS after readmission, and readmission costs (sum of all costs, i.e., patient charges, hospital costs and insurance claims). Patients readmitted were stratified into 10 separate subgroups depending on the primary cause of readmission: cardiac, endocrine, hematological, infectious, gastrointestinal, musculoskeletal (MSK), neoplastic, neurological or psychiatric, pulmonary, and renal causes.
Pearson’s chi-square was used to compare patient demographics, and multivariate binomial logistic regression was used to calculate odds ratios (OR) on patient-related risk factors for 90-day readmissions. Risk factors assessed were those comorbidities, which comprise the Elixhauser-Comorbidity Index (ECI), which has been shown to be superior to the Charlson-Comorbidity Index (CCI) for observational studies (Table 1).
  • Maron S.Z.
  • Neifert S.N.
  • Ranson W.A.
  • et al.
Elixhauser comorbidity measure is superior to Charlson Comorbidity Index in predicting hspital complications following elective posterior cervical decompression and fusion.
A P value less than .05 was considered statistically significant. The study received IRB Category 4 exemption.
Table 1Comparison of Demographics of Readmitted Patients to Controls After Arthroscopic Rotator Cuff Repair Within the Medicare Population
DemographicsReadmitted (N = 10,425)Controls (N = 301,625)P Value
n%n%
Age (Years)<.0001
Assessed by Pearson’s chi-square analyses.
 <642,56024.5654,38218.03
 65-692,71926.08108,46535.96
 70-742,34022.4575,96925.19
 75-791,73316.6243,25214.34
 80-848287.9415,9005.27
 85+2452.353,6571.21
Sex.624
Assessed by Pearson’s chi-square analyses.
 Female5,24750.33152,56150.58
 Male5,17849.67149,06449.42
Region<.0001
Assessed by Pearson’s chi-square analyses.
 Midwest2,63225.2571,93123.85
 Northeast1,63315.6649,89916.54
 South4,77145.76133,89044.39
 West1,38213.2645,90515.22
Comorbidities
 Alcohol abuse1,0269.8412,9024.28<.0001
Assessed by Pearson’s chi-square analyses.
 Blood loss anemia8788.4210,6273.52<.0001
Assessed by Pearson’s chi-square analyses.
 Cardiac arrhythmias4,84246.4586,88628.81<.0001
Assessed by Pearson’s chi-square analyses.
 Chronic pulmonary disease5,96057.17112,85437.42<.0001
Assessed by Pearson’s chi-square analyses.
 Coagulopathy1,98219.0128,1919.35<.0001
Assessed by Pearson’s chi-square analyses.
 Congestive heart failure3,58234.3645,00214.92<.0001
Assessed by Pearson’s chi-square analyses.
 Deficiency anemia5,76955.34100,63333.36<.0001
Assessed by Pearson’s chi-square analyses.
 Depression4,74145.4882,20927.26<.0001
Assessed by Pearson’s chi-square analyses.
 Diabetes mellitus (complicated)2,01719.3528,2079.35<.0001
Assessed by Pearson’s chi-square analyses.
 Diabetes mellitus (uncomplicated)5,12249.13110,64836.68<.0001
Assessed by Pearson’s chi-square analyses.
 HIV610.597330.24<.0001
Assessed by Pearson’s chi-square analyses.
 Hypertension9,62792.35248,97082.54<.0001
Assessed by Pearson’s chi-square analyses.
 Hypothyroidism3,50633.6382,81027.45<.0001
Assessed by Pearson’s chi-square analyses.
 Liver disease1,49614.3523,8437.90<.0001
Assessed by Pearson’s chi-square analyses.
 Lymphoma3583.436,1722.05<.0001
Assessed by Pearson’s chi-square analyses.
 Metastatic cancer5945.7010,6683.54<.0001
Assessed by Pearson’s chi-square analyses.
 Neurodegenerative disorders1,92418.4628,3069.38<.0001
Assessed by Pearson’s chi-square analyses.
 Obesity (BMI, 30-39.9)1,54114.7822,6437.51<.0001
Assessed by Pearson’s chi-square analyses.
 Morbid obesity (BMI, ≥40)8678.3210,6723.53<.0001
Assessed by Pearson’s chi-square analyses.
 Paralysis6175.927,5232.49<.0001
Assessed by Pearson’s chi-square analyses.
 Peptic ulcer disease excluding bleeding1,57915.1524,3228.06<.0001
Assessed by Pearson’s chi-square analyses.
 Peripheral vascular disease3,88337.2569,04022.89<.0001
Assessed by Pearson’s chi-square analyses.
 Pulmonary circulation disorders1,33512.8115,9965.30<.0001
Assessed by Pearson’s chi-square analyses.
 Renal failure8538.1810,3713.44<.0001
Assessed by Pearson’s chi-square analyses.
 Rheumatoid arthritis1,95218.7240,60913.46<.0001
Assessed by Pearson’s chi-square analyses.
 Valvular disease3,03629.1257,76319.15<.0001
Assessed by Pearson’s chi-square analyses.
 Weight loss1,18311.3511,7353.89<.0001
Assessed by Pearson’s chi-square analyses.
 ECI ± SD9 ± 45 ± 4<.0001
Assessed by independent samples t-tests.
BMI, body mass index; ECI, Elixhauser-Comorbidity Index; HIV, human immunodeficiency virus; RCR, rotator cuff repair; SD, standard deviation. Bolded values indicate significant difference.
a Assessed by Pearson’s chi-square analyses.
b Assessed by independent samples t-tests.

Results

A total of 10,425 readmitted patients and 301,625 control patients were identified, representing a 90-day readmission rate of 3.5%. There was a statistically significant difference between the cohorts in age (P < .0001) and comorbidity burden, as measured by the mean ECI scores (9 vs. 5, P < .0001). Gender distribution between the two cohorts was equal (P = .63) (Table 1). The most common reasons for readmission were related to infection (15%), musculoskeletal (MSK) (15%), and cardiac (14%) complications. Complete readmission rates for each subgroup are displayed in Fig 1.
Figure thumbnail gr1
Fig 1Readmission causes after arthroscopic rotator cuff repair.
The most common MSK readmissions were osteoarthrosis of the leg or shoulder (24.8%) and spinal spondylosis (8.4%). Rotator cuff sprain and retearing of the repaired rotator cuff represented 5.2% and 2.0% of total MSK readmissions, respectively. When individual diagnoses were examined, the most common reasons for readmission overall were pneumonia (3.85%), pulmonary embolism (3.24%), coronary arthrosclerosis (2.94%), and postoperative infection (2.91%) (Table 2).
Table 2Multivariable Regression: Patient Related Factors Associated with 90-Day Readmissions Following Arthroscopic Rotator Cuff Repair
VariablesOdds Ratio95% CIP Value
Assessed by Pearson’s chi-square analyses.
Age (Years)
 75-790.990.92–1.06.686
 80–841.141.04–1.25.003
 >851.361.17–1.57<.001
Sex
 Male1.171.13–1.23<.001
Risk Factors
 Alcohol abuse1.421.32–1.52<.001
 Morbid obesity (BMI, ≥40)1.381.27–1.49<.001
 Depression1.351.30–1.42<.001
 Obesity (BMI, 30-39.9)1.351.27–1.43<.001
 Congestive heart failure1.341.27–1.41<.001
 Chronic pulmonary disease1.281.22–1.33<.001
 Deficiency anemia1.261.20–1.32<.001
 Paralysis1.231.13–1.34<.001
 Weight loss1.221.13–1.31<.001
 Neurodegenerative disorders1.211.15–1.28<.001
 Cardiac arrhythmias1.201.14–1.25<.001
 Blood loss anemia1.191.10–1.29<.001
 Peptic ulcer disease excluding bleeding1.181.11–1.25<.001
 Liver disease1.171.10–1.24<.001
 Pulmonary circulation disorders1.171.10–1.26<.001
 Diabetes mellitus (complicated)1.161.10–1.24<.001
 Coagulopathy1.151.09–1.21<.001
 Lymphoma1.100.98–1.23.105
 Peripheral vascular disease1.101.05–1.15<.001
 Hypertension1.050.44–2.08.904
 Metastatic cancer1.040.95–1.13.391
 Renal failure1.020.94–1.10.641
 Rheumatoid arthritis0.980.93–1.03.496
 Hypothyroidism0.960.91–1.00.051
 Diabetes mellitus (uncomplicated)0.950.72–1.28.743
 Valvular disease0.950.90–1.00.052
95% CI, 95% confidence interval; BMI, body mass index. Bolded values signify statistical significance.
a Assessed by Pearson’s chi-square analyses.
Multivariate binomial logistic regression analyses demonstrated patients with alcohol abuse (OR, 1.42; P < .0001), morbid obesity (OR, 1.38; P < .0001), depression (OR, 1.35; P < 0.0001), congestive heart failure (OR, 1.34; P < .0001), and/or chronic pulmonary disease (OR, 1.28; P < .0001) listed as comorbidities were at the greatest risk of readmissions after RCR. Age greater than 85 years (OR, 1.36; P < .001) and male gender (OR, 1.17; P < .001) were also risk factors for readmission. Complete list of patient-related factors associated with 90-day readmissions is shown in Table 3.
Table 3Common Reasons for Readmissions within 90 Days After Arthroscopic Rotator Cuff Repair
Cause of Readmission%
Pneumonia3.85
Pulmonary embolism3.24
Coronary atherosclerosis2.94
Postoperative infection2.91
Chest pain2.51
Atrial fibrillation2.27
Obstructive chronic bronchitis1.88
Acute kidney failure1.80
Subendocardial infraction1.67
Osteoarthrosis1.40
Readmissions that resulted in the longest in-hospital lengths-of-stay included neoplastic (5.6 days), neurologic/psychiatric (4.8 days) and infectious (4.7 days) related complications (Fig 2). Readmissions associated with the highest mean episode of care costs were neoplastic ($13,602), MSK ($10,903), and cardiac ($10,436) (Fig 3). While cardiac and MSK-related readmissions represented the greatest mean costs per day ($3,097 and $3,088; Fig 4).
Figure thumbnail gr2
Fig 2Mean length of stay in hospital based on readmissions causes.
Figure thumbnail gr3
Fig 3Mean episode of care costs on causes of readmission.
Figure thumbnail gr4
Fig 4Mean episode of care cost per day based on causes of readmission.

Discussion

Arthroscopic RCR is one of the most frequently performed orthopaedic procedures, routinely performed for the treatment of rotator cuff tears refractory to nonsurgical options.
  • Zhang A.L.
  • Montgomery S.R.
  • Ngo S.S.
  • Hame S.L.
  • Wang J.C.
  • Gamradt S.C.
Analysis of rotator cuff repair trends in a large private insurance population.
,
  • Gilotra M.
  • O’Brien M.J.
  • Savoie 3rd, F.H.
Arthroscopic rotator cuff repair: Indication and technique.
,
  • Clement N.D.
  • Nie Y.X.
  • McBirnie J.M.
Management of degenerative rotator cuff tears: A review and treatment strategy.
Despite such high utilization, limited studies have described patient characteristics and risk factors related to 90-day readmissions among patient undergoing arthroscopy.
  • Khazi Z.M.
  • Lu Yining
  • Cregar W.
  • et al.
Inpatient arthropcopic rotator cuff repair is associated with higher postoperative complications compared with same-day discharge: A matched cohort analysis.
Our study found the readmission rate following arthroscopic RCR to be ∼3.5%, which is consistent to our hypothesis. The three predominant causes for readmission were related to infectious diseases (15%), MSK (15%), and cardiac (14%). When looking at specific diagnoses, the leading causes of readmission were pneumonia (3.85%), pulmonary embolism (3.24%), coronary atherosclerosis (2.94%), and postoperative infection (2.91%). Multivariate analysis revealed primary risk factors for readmissions to be alcohol abuse, morbid obesity, depression, congestive heart failure, and chronic pulmonary disease. Arthroscopic RCR is one of the most frequently performed orthopaedic procedures, routinely performed for the treatment of rotator cuff tears refractory to nonsurgical options.
  • Zhang A.L.
  • Montgomery S.R.
  • Ngo S.S.
  • Hame S.L.
  • Wang J.C.
  • Gamradt S.C.
Analysis of rotator cuff repair trends in a large private insurance population.
,
  • Gilotra M.
  • O’Brien M.J.
  • Savoie 3rd, F.H.
Arthroscopic rotator cuff repair: Indication and technique.
,
  • Clement N.D.
  • Nie Y.X.
  • McBirnie J.M.
Management of degenerative rotator cuff tears: A review and treatment strategy.
Despite such high utilization, limited studies have described patient characteristics and risk factors related to 90-day readmissions among patients undergoing arthroscopic.
  • Khazi Z.M.
  • Lu Yining
  • Cregar W.
  • et al.
Inpatient arthropcopic rotator cuff repair is associated with higher postoperative complications compared with same-day discharge: A matched cohort analysis.
Previous literature consistently demonstrates several common medical comorbidities and substance abuse problems amongst patients who suffer from rotator cuff injuries. These include alcohol use, diabetes mellitus, hyperlipidemia, hypertension, concomitant musculoskeletal disease, obesity, and tobacco use.
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  • White J.J.E.
  • Hinchliffe S.R.
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Comorbidities in rotator cuff disease: A case-control study.
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Diabetes mellitus increases the risk of rotator cuff tear repair surgery: A population-based cohort study.
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  • Gumina S.
Association between alcohol consumption and rotator cuff tear.
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Osteoarthritis of the glenohumeral joint: A radiologic-pathologic study.
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The association between arterial hypertension and rotator cuff tear: The influence on rotator cuff tear sizes.
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  • et al.
Cigarette smoking increases the risk for rotator cuff tears.
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  • Kim J.S.
The effect of hypercholesterolemia on rotator cuff disease.
In a case control study of 5,000 patients, Titchener et al. described increased BMI, lateral epicondylitis, carpal tunnel syndrome, trigger finger, Achilles tendinitis, oral corticosteroid use, and diabetes mellitus as comorbidities significantly associated with rotator cuff injuries.
  • Titchener A.G.
  • White J.J.E.
  • Hinchliffe S.R.
  • Tambe A.A.
  • Hubbard R.B.
  • Clark D.I.
Comorbidities in rotator cuff disease: A case-control study.
Another study demonstrated long-term alcohol use to be a significant risk factor in the development of rotator cuff tears.
  • Passaretti D.
  • Candela V.
  • Venditto T.
  • Giannicola G.
  • Gumina S.
Association between alcohol consumption and rotator cuff tear.
Our study supports the findings of these studies and further details that readmission following arthroscopic RCR is associated with increased number of preexisting comorbidities. Moreover, surgeons should be aware that the proper screening of prevalent comorbidities (alcohol abuse, morbid obesity, and depression) are vital for patient outcome optimization.
The cause of readmission following arthroscopic RCR has been addressed in several studies.
  • Hill J.R.
  • McKnight B.
  • Pannell W.C.
  • et al.
Risk factors for 30-day readmission following shoulder arthroscopy.
,
  • Sherman S.L.
  • Lyman S.
  • Koulouvaris P.
  • Willis A.
  • Marx R.G.
Risk factors for readmission and revision surgery following rotator cuff repair.
Day et al. found a 30-day complication rate of 1.17% following arthroscopic RCR, with a greater incidence of medical complications compared to surgical (0.67% vs. 0.27%).
  • Day M.
  • Westermann R.
  • Duchman K.
  • et al.
Comparison of short-term complications after rotator cuff repair: Open versus arthroscopic.
In a retrospective study of 15,015 patients undergoing arthroscopic shoulder procedures, of which 43% were rotator cuff repairs, Hill et al. observed the most common reasons for 30-day readmission were pulmonary embolism (PE), exacerbation of respiratory disease or respiratory failure, venous thromboembolism (VTE), postoperative pain, pneumonia, and wound complications. Using multivariate analysis, the authors demonstrated chronic obstructive pulmonary disease (COPD) as a predominant risk factor for 30-day readmission, consistent with our findings.
  • Hill J.R.
  • McKnight B.
  • Pannell W.C.
  • et al.
Risk factors for 30-day readmission following shoulder arthroscopy.
Similarly, Kosinski et al. found the most common complications associated with 30-day readmissions after outpatient RCR were of cardiovascular, infectious, and respiratory origin.
  • Kosinski L.R.
  • Gil J.A.
  • Durand W.M.
  • DeFroda S.F.
  • Owens B.D.
  • Daniels A.H.
30-Day readmission following outpatient rotator cuff repair: An analysis of 18,061 cases.
The causes of 90-day readmissions in our study are similar with what is reported in the literature, suggesting the majority of complications following arthroscopic RCR are due to medical complications, rather than associated with the reinjury or retear of the rotator cuff. However, these complications are likely associated with the index procedure itself, as surgical procedures carry inherent risk of infection and thromboembolic events.
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A systematic review of risk factors associated with surgical site infections among surgical patients.
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  • Brant R.
  • Ghali W.A.
Association of postoperative complications with hospital costs and length of stay in a tertiary care center.
The common postoperative infections encountered following surgical procedures include pneumonia and surgical site infections (SSI).
  • Shields E.
  • Thirukumaran C.
  • Thorsness R.
  • Noyes K.
  • Voloshin I.
An analysis of adult patient risk factors and complications within 30 days after arthroscopic shoulder surgery.
,
  • Khan N.A.
  • Quan H.
  • Bugar J.M.
  • Lemaire J.B.
  • Brant R.
  • Ghali W.A.
Association of postoperative complications with hospital costs and length of stay in a tertiary care center.
In a study of 7,457 patients undergoing various noncardiac surgical procedures, Kahn at al. found pneumonia to be the most common postoperative complication with an incidence of 3.0%.
  • Khan N.A.
  • Quan H.
  • Bugar J.M.
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  • Brant R.
  • Ghali W.A.
Association of postoperative complications with hospital costs and length of stay in a tertiary care center.
Additionally, SSI’s are a predominant cause of postoperative infections in surgical patients and account for 15% of total nosocomial infections.
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Reducing surgical site infections: A review.
Additionally, occurrence of venous thromboembolism in elective shoulder surgery arthroscopy vary, with reported rates ranging from 0.15% to 5.7%.
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  • Gao Y.
  • Wolf B.R.
Thromboembolism following shoulder arthroscopy: A retrospective review.
,
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  • Itoi E.
Venous thromboembolism after elective shoulder surgery: A prospective cohort study of 175 patients.
Overall, our findings appear to be consistent with previous literature regarding complications following arthroscopic RCR. Thus, surgeons should be aware that postoperative monitoring for an infection and thrombotic events is paramount to decreasing hospitalization.
Rates of rotator cuff retear after RCR vary greatly and are thought to be relatively high, with greatest occurrence within 6 months postoperatively.
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The clinical and structural long-term results of open repair of massive tears of the rotator cuff.
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Intraoperative determinants of rotator cuff repair integrity: An analysis of 500 consecutive repairs.
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Repair integrity and functional outcome after arthroscopic double-row rotator cuff repair. A prospective outcome study.
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  • Wu X.L.
  • Lam P.H.
  • Murrell G.A.C.
Factors predicting rotator cuff retears: An analysis of 1000 consecutive rotator cuff repairs.
  • Huijsmans P.E.
  • Pritchard M.P.
  • Berghs B.M.
  • van Rooyen K.S.
  • Wallace A.L.
  • de Beer J.F.
Arthroscopic rotator cuff repair with double-row fixation.
  • Galatz L.M.
  • Ball C.M.
  • Teefey S.A.
  • Middleton W.D.
  • Yamaguchi K.
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  • Rossi L.A.
  • Chahla J.
  • Verma N.N.
  • Millett P.J.
  • Ranalletta M.
Rotator cuff retears.
Evidence supports a steadily increasing risk of retear in medium-to-large rotator cuff tears 10–15 months following arthroscopic RCR, after which retear rates appear to plateau at 20%.
  • Chona D.V.
  • Lakomkin N.
  • Lott A.
  • et al.
The timing of retears after arthroscopic rotator cuff repair.
Causes of rotator cuff retear after RCR are likely multifactorial. Studies have postulated causes of retear are affected by patient age, comorbidities, size of rotator cuff tears, and degree of fatty infiltration within the tear.
  • Bishop J.
  • Klepps S.
  • Lo I.K.
  • Bird J.
  • Gladstone J.N.
  • Flatow E.L.
Cuff integrity after arthroscopic versus open rotator cuff repair: a prospective study.
  • Nakamura H.
  • Gotoh M.
  • Mitsui Y.
  • et al.
Factors affecting clinical outcome in patients with structural failure after arthroscopic rotator cuff repair.
  • Tashjian R.Z.
  • Hollins A.M.
  • Kim H.-M.
  • et al.
Factors affecting healing rates after arthroscopic double-row rotator cuff repair.
  • Neyton L.
  • Godenèche A.
  • Nové-Josserand L.
  • Carrillon Y.
  • Cléchet J.
  • Hardy M.B.
Arthroscopic suture-bridge repair for small to medium size supraspinatus tear: Healing rate and retear pattern.
  • Chen A.L.
  • Shapiro J.A.
  • Ahn A.K.
  • Zuckerman J.D.
  • Cuomo F.
Rotator cuff repair in patients with type I diabetes mellitus.
  • Bishop J.Y.
  • Santiago-Torres J.E.
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  • Flanigan D.C.
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Varied reporting of retear rates are likely due to the aforementioned factors in addition to inconsistent time periods analyzed following the index procedure. Most studies of this nature analyze postoperative periods greater than 90 days.
  • Chona D.V.
  • Lakomkin N.
  • Lott A.
  • et al.
The timing of retears after arthroscopic rotator cuff repair.
However, Tanaka et al. reported retear rates of 2.9% in medium-sized rotator cuff tears 90 days following arthroscopic RCR.
  • Tanaka M.
  • Hayashida K.
  • Kobayashi A.
  • Kakiuchi M.
Arthroscopic rotator cuff repair with absorbable stures in the medial-row anchors.
Though scarce, existing literature supports our findings of retears being responsible for 2.0% of musculoskeletal related readmission 90 days following arthroscopic RCR.
  • Tanaka M.
  • Hayashida K.
  • Kobayashi A.
  • Kakiuchi M.
Arthroscopic rotator cuff repair with absorbable stures in the medial-row anchors.
Literature regarding costs associated with readmission-related complications following arthroscopic RCR is lacking. However, data analyzing readmission costs attributed to complications found in our study, including cardiac, musculoskeletal, and neoplastic, are available.
  • Smilowitz N.R.
  • Beckman J.A.
  • Sherman S.E.
  • Berger J.S.
Hospital readmission after perioperative acute myocardial infarction associated with noncardiac surgery.
  • Clair A.J.
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  • Slover J.D.
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Among the most common reasons for readmission in our study, musculoskeletal complications’ economic burden is commonly documented.
  • Losina E.
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  • Weinstein A.M.
  • et al.
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  • Bitton R.
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  • Reveille J.D.
  • Ximenes A.
  • Ward M.M.
Economic considerations of the treatment of ankylosing spondylitis.
  • Akkoç N.
  • Direskeneli H.
  • Erdem H.
  • et al.
Direct and indirect costs associated with ankylosing spondylitis and related disease activity scores in Turkey.
  • Verstappen S.M.M.
  • Jacobs J.W.G.
  • van der Heijde D.M.
  • et al.
Utility and direct costs: Ankylosing spondylitis compared with rheumatoid arthritis.
Further subgroup analysis revealed osteoarthritis (OA) of the knee and ankylosing spondylitis to be the most prevalent musculoskeletal causes of readmission. Not as predominant, although of great interest to orthopaedic surgeons, our study found infectious disease was the cause of significant costs following readmission, consistent with existing literature on the topic.
  • Perencevich E.N.
  • Sands K.E.
  • Cosgrove S.E.
  • Guadagnoli E.
  • Meara E.
  • Platt R.
Health and economic impact of surgical site infections diagnosed after hospital discharge.
,
  • Olasupo O.
  • Xiao H.
  • Brown J.D.
Relative clinical and cost burden of community-acquired pneumonia hospitalizations in older adults in the United States—A cross-sectional analysis.
In a retrospective study of 4,571 patients, Perencevich et al. found patients who were diagnosed with surgical site infections (SSI) over an 8-week period, incurred nearly 3 times the costs than the control cohort.
  • Perencevich E.N.
  • Sands K.E.
  • Cosgrove S.E.
  • Guadagnoli E.
  • Meara E.
  • Platt R.
Health and economic impact of surgical site infections diagnosed after hospital discharge.
Furthermore, the economic burden associated with complications of neoplastic origin have been documented in the literature.
  • Trogdon J.G.
  • Falchook A.D.
  • Basak R.
  • Carpenter W.R.
  • Chen R.C.
Total Medicare costs associated with diagnosis and treatment of prostate cancer in elderly men.
  • Cipriano L.E.
  • Romanus D.
  • Earle C.C.
  • et al.
Lung cancer treatment costs, including patient responsibility, by disease stage and treatment modality, 1992 to 2003.
  • Hollenbeak C.S.
  • Nikkel L.E.
  • Schaefer E.W.
  • Alemao E.
  • Ghahramani N.
  • Raman J.D.
Determinants of Medicare all-cause costs among elderly patients with renal cell carcinoma.
,
  • Knust R.E.
  • Portela M.C.
  • Pereira CC. de A.
  • Fortes G.B.
Estimated costs of advanced lung cancer care in a public reference hospital.
,
  • Nadeem H.
  • Jayakrishnan T.T.
  • Rajeev R.
  • Johnston F.M.
  • Gamblin T.C.
  • Turaga K.K.
Cost differential of chemotherapy for solid tumors.
Our study found cardiac, musculoskeletal, and neoplastic causes of readmission were associated with the highest costs on a per day basis, respectively. Furthermore, neoplastic, MSK, and cardiac complications were responsible for the greatest total per episode costs following readmission, respectively.
The information in this study can help orthopaedic surgeons properly screen preoperative patients, as well as help optimize the care of patients that are considered higher risk for rehospitalizations. In the future, large cohort studies and multicenter studies are needed to identify the specific micro-organisms causing infection, as well to identify the proper postoperative protocols for decreasing thromboembolic events in order to decrease rehospitalizations following arthroscopic RCR.

Limitations

This study is not without limitations. Because of the nature of the database, only Medicare patients from 2005 to 2014 could be queried, which can contribute to a selection bias. Moreover, the data from these Medicare patients are associated with increased comorbidities, specifically in the <65-year-old population. The data may also not necessarily correlate with the commercial population or with the recent advances in arthroscopic surgery; however, the findings may still be generalizable and impact patient care. It was also not possible to analyze the timing of the causes for readmission between what the current literature reports at 30 days and our time point of 90 days. Additionally, the study relies on accurate reporting of ICD-9 codes, which have an error rate of ∼1%.
  • Cancienne J.M.
  • Dempsey I.J.
  • Holzgrefe R.E.
  • Brockmeier S.F.
  • Werner B.C.
Is hepatitis C infection associated with a higher risk of complications after total shoulder arthroplasty?.
,
  • Yoshihara H.
  • Yoneoka D.
Understanding the statistics and limitations of large database analyses.
Because of the nature of the ICD-9 code-based criteria, it is not possible to determine the severity of the medical conditions, frequency of substance abuse, or interventional treatment patients may be undergoing for certain comorbidities. Furthermore, the results demonstrate statistical significance among several variables and 90-day readmission risk; this does not necessarily correlate with clinical significance.

Conclusion

Significant differences exist among patients readmitted and those patients who do not require hospital readmission within 90 days following arthroscopic rotator cuff repairs. Readmissions are associated with significant patient comorbidities and were primarily related to medically based complications.

Supplementary Data

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