Treatment of First Carpometacarpal Osteoarthritis with Arthroscopy: A Systematic Review.

Background First carpometacarpal (CMC) osteoarthritis or trapeziometacarpal osteoarthritis is a common debilitating hand condition. No one surgical technique has demonstrated superiority in managing this disease. Purpose This study performed a systematic review of arthroscopic techniques for treating first CMC arthritis to assess the effectiveness of different arthroscopic techniques. Methods Grip strength, pinch strength, visual analog scale, the Disability of Arm, Shoulder, and Hand (DASH) score, range of motion (ROM), and complications were recorded. Two subgroup analyses were performed, comparing outcomes of (1) trapeziectomy of any type versus debridement alone and (2) trapeziectomy alone versus interposition versus suspension techniques. Results Preoperative and postoperative scores significantly improved for DASH scores and pain at rest and with activity with variable improvements in ROM. Complications occurred in 13% of cases in publications that reported complications. When comparing studies that utilized techniques with any type of trapeziectomy to debridement alone, only the trapeziectomy subgroup showed significant improvements in pain. When comparing trapeziectomy alone to interposition and suspension techniques, mean DASH scores and pain levels significantly improved in interposition and suspension subgroups. Conclusions The existing literature describes a predominantly female population with Eaton-Littler stage II and III disease. In the subgroup analysis, arthroscopic techniques involving a trapeziectomy seem to be more effective at lowering pain scores compared to techniques involving debridement alone. Likewise, interposition and suspension techniques may show improved outcomes compared to techniques involving trapeziectomy alone. Level of evidence This is a Level III study.

Identifying Patients at Risk for Venous Thromboembolic Events After Isolated Upper Extremity Trauma: A Predictive Scale.

Previous studies have defined risk factors for development of venous thromboembolisms (VTEs) among patients with lower extremity orthopedic trauma. Limited data exist on this risk after upper extremity orthopedic trauma. A total of 269,137 incidents of upper extremity orthopedic trauma (fractures of the clavicle, scapula, humerus, elbow, or lower arm) were identified in the State Inpatient Database for 4 states included in the analysis (California, Florida, New York, and Washington) from 2006 to 2014. These patients were split into 2 cohorts, a derivation cohort (California and New York) and a validation cohort (Florida and Washington). Univariate and multivariate logistic regression analyses of risk factors for VTE within 90 days of discharge in the derivation group were used to develop the Thromboembolic Risk after Upper Extremity Trauma (TRUE-T) scale. Linear regression was used to determine fit of the TRUE-T scale to the 2 cohorts. We found that 2.61% of patients in the derivation cohort and 2.72% of patients in the validation cohort had a VTE within 90 days of discharge. Risk factors associated with increased rates of VTE were age older than 40 years, Medicare payer, anemia, chronic lung disease, coagulopathy, heart failure, malignancy, obesity, renal failure, head injury, chest injury, abdominal injury, rib fracture, humerus fracture, elbow fracture, and closed reduction. Application of the TRUE-T scale to the validation cohort showed an R2 value of 0.88. The patient factors, concomitant injuries, and fracture treatment modalities included in the TRUE-T scale can be used to identify patients at increased risk for VTE after upper extremity orthopedic trauma. [Orthopedics. 2022;45(6):345-352.].

Distal Humerus Traction Radiographs: Is the Interobserver and Intraobserver Reliability Comparable With Computed Tomography?

OBJECTIVES: To compare the interobserver and intraobserver reliability of traction radiographs with 2-dimensional computed tomography (2D CT) in distal humerus fracture classification and characterization. DESIGN: Randomized controlled radiographic review of retrospectively collected data. SETTING: Academic Level 1 trauma center. PATIENTS/PARTICIPANTS: Skeletally mature patients with intra-articular distal humerus fractures with both traction radiographs and CT scans were reviewed by 11 orthopaedists from different subspecialties and training levels. INTERVENTION: The intervention involved traction radiographs and 2D CT. MAIN OUTCOME MEASUREMENTS: The main outcome measurements included interobserver and intraobserver reliability of fracture classification by the OTA/AO and Jupiter-Mehne and determination of key fracture characteristics. RESULTS: For the OTA/AO and Jupiter-Mehne classifications, we found a moderate intraobserver agreement with both 2D CT and traction radiographs (κ = 0.70-0.75). When compared with traction radiographs, 2D CT improved the interobserver reliability of the OTA/AO classification from fair to moderate (κ = 0.3 to κ = 0.42) and the identification of a coronal fracture from slight to fair (κ = 0.2 to κ = 0.34), which was more pronounced in a subgroup analysis of less-experienced surgeons. When compared with 2D CT, traction radiographs improved the intraobserver reliability of detecting stable affected articular fragments from fair to substantial (κ = 0.4 to κ = 0.67). CONCLUSIONS: Traction radiographs provide similar diagnostic characteristics as 2D CT in distal humerus fractures. For less-experienced surgeons, 2D CT may improve the identification of coronal fracture lines and articular comminution.

Identification of Risk Factors for Readmission in Patients Undergoing Anterior Cervical Discectomy Fusion: A Predictive Risk Scale.

STUDY DESIGN: This was a retrospective cohort study. OBJECTIVE: The objective of this study was to analyze readmission rates among patients undergoing anterior cervical discectomy and fusion (ACDF), determine which factors were associated with higher readmission rates, and develop a scale for utilization during surgical planning. SUMMARY OF BACKGROUND DATA: ACDF is the most common surgical treatment for many cervical disk pathologies. With the Centers for Medicare and Medicaid Services selecting readmissions as a measure of health care quality, there has been an increased focus on reducing readmissions. MATERIALS AND METHODS: There were 114,174 recorded ACDF surgeries in the derivation cohort, the State Inpatient Database (SID) of New York and California between 2006 and 2014. There were 115,829 ACDF surgeries recorded in the validation cohort, the SID from Florida and Washington over the same time period. After identification of risk factors using univariate and multivariate analysis of the derivation cohort, a predictive scale was generated and tested utilizing the validation cohort. RESULTS: Overall, readmission rates within 30 days of discharge were 5.87% and 5.52% in the derivation and validation cohorts, respectively. On multivariate analysis of the derivation cohort, age older than 80 years [odds ratio (OR), 1.67] male sex (OR, 1.16), Medicaid insurance (OR, 1.90), Medicare insurance (OR, 1.64), revision ACDF (OR, 1.43), anemia (OR, 1.45), chronic lung disease (OR, 1.23), coagulopathy (OR, 1.42), congestive heart failure (OR, 1.31), diabetes (OR, 1.23), fluid and electrolyte disorder (OR, 1.56), liver disease (OR, 1.37), renal failure (OR, 1.59), and myelopathy (OR, 1.19) were found to be statistically significant predictors for readmission. These factors were incorporated into a numeric scale that, that when tested on the validation cohort, could explain 97.1% of the variability in readmission rate. CONCLUSIONS: Overall, 30-day readmission following ACDF surgery was 5%-6%. A novel risk scale based on factors associated with increased readmission rates may be helpful in identifying patients who require additional optimization to reduce perioperative morbidity. LEVEL OF EVIDENCE: Level III-prognostic.

Reconstruction with Custom Unicondylar Hemiarthroplasty following Tumor Resection: A Case Series and Review of the Literature.

For patients with tumors of the distal femur, options for limb salvage include tumor resection followed by reconstruction. While reconstruction commonly involves a distal femoral replacement, careful selection of patients with tumor involvement limited to a single condyle may be candidates for reconstruction with distal femur hemiarthroplasty. In these procedures, resection spares considerably more native anatomy. Three consecutive patients who underwent resection and reconstruction at the distal femur with custom unicondylar hemiarthroplasty are presented in this case series at a mean follow-up of 45 months (range, 26-78). In two cases, prostheses were utilized as a secondary procedure after failure of initial reconstruction. In one case, the custom prosthesis was utilized as the primary method of reconstruction. Mean Musculoskeletal Tumor Society disease-specific scores were 26.7 (range, 25-28). All patients achieved a return to full weight bearing, activities of daily living, and functional range of motion. In appropriately selected patients with tumors of the distal femur, reconstruction with custom unicondylar hemiarthroplasty provides benefits including optimal function postoperatively via preservation of tumor-free bone and ligamentous structures. Additionally, maintenance of greater bone stock may confer benefits to patients with pathology at a high likelihood for recurrence and need for subsequent procedures.

The Incidence of Snow Blower-Related Injuries to the Hand in the United States.

BACKGROUND: Snow blowers represent a highly preventable and increasingly common mechanism of hand injury. This study examines current safety features and their impact on decreasing the incidence of snow blower-related injuries. METHODS: The National Electronic Injury Surveillance System was queried to look for injuries related to the use of snow throwers or blowers between 2001 and 2016. From all of the injuries related to snow blowers, we collected information on identifying characteristics, location of injury, and type of injury (i.e., avulsion). Chi-squared tests were used for categorical variable comparisons, and Student t tests were used for continuous variable comparisons. Data analysis was performed using SAS statistical software, version 9.3 (SAS Institute, Inc., Cary, NC). The Consumer Product Safety Commission's provided SAS algorithm was used to calculate all national injury estimates and variances. Statistical significance was determined based on P < 0.05. RESULTS: Within the study period, there were 3,550 reported injuries. The extrapolated national incidence was 92,799, with an average annual incidence of 5,800 or 1.9 injuries per 100,000 US population per year. The most commonly injured body part was the finger followed by the hand. Most common types of injuries were fractures, lacerations, and amputations. CONCLUSIONS: The incidence of snow blower injuries increased from 2001 to 2016. Unlike with other power tools, Consumer Product Safety Commission-mandated guidelines for safer operation and improvements in equipment have not been successful in producing a decrease in the incidence of snow blower injuries to the upper extremity. Based on this, further equipment modifications are necessary and should be aimed at preventing operators from placing their hand into the exit chute while the machine is still running. Physicians should take an active role in their practice as well as in their professional societies to educate and counsel patients to prevent further injury.

Injuries sustained during high intensity interval training: are modern fitness trends contributing to increased injury rates?

BACKGROUND: Over the past decade, interest in high intensity interval training (HIIT) has increased considerably. The objective of this study was to determine injury incidence coinciding with increased popularity of HIIT and identify ways physicians can advise patients prior to participation. METHODS: The National Electronic Injury Surveillance System (NEISS) was queried from 2007 through 2016 to estimate injury incidence related to exercises such as burpees, push-ups, and lunges and exercise equipment such as barbells, kettle bells, and boxes, which are representative of HIIT exercise programs. Injury incidences were calculated and compared between 2007-2011 and 2012-2016. Over the same time period, Google Trends was used to determine the popularity of HIIT. RESULTS: There were an estimated 3,988,903 injuries, most often in males (58%) aged 20 to 39 years (39%). Most commonly, injuries were in the lower extremity (35.3%), trunk (28.5%), and upper extremity (19.6%). From 2012-2016 versus 2007-2011, there was a 144% increase in all injuries including a 159% increase in trunk injuries, a 137% increase in lower extremity injuries, and a 132% increase in upper extremity injuries. There was also a 127% increase in lower extremity strains and a 124% increase in upper extremity strains. Additionally, knee and ankle sprains increased 125%. These increases in injury incidence correlated with a 274% increase in HIIT interest. CONCLUSIONS: Given increases in injuries related to high-intensity workout programs, athletes should be educated on how to minimize preventable injuries. With particularly high rates of knee and ankle sprains and strains, neuromuscular training and pre-strengthening programs, which have been previously demonstrated to be effective among young athletes, may be particularly worthwhile in prospective participants. Physicians must be up to date with current fitness trends to best advise patients appropriately.

Determining 30-day readmission risk for heart failure patients: the Readmission After Heart Failure scale.

BACKGROUND: Chronic heart failure (CHF), which affects >5 million Americans, accounts for >1 million hospitalizations annually. As a part of the Hospital Readmission Reduction Program, the Affordable Care Act requires that the Centers for Medicare and Medicaid Services reduce payments to hospitals with excess readmissions. This study sought to develop a scale that reliably predicts readmission rates among patients with CHF. METHODS: The State Inpatient Database (2006-2011) was utilized, and discharge data including demographic and clinical characteristics on 642,448 patients with CHF from California and New York (derivation cohort) and 365,359 patients with CHF from Florida and Washington (validation cohort) were extracted. The Readmission After Heart Failure (RAHF) scale was developed to predict readmission risk. RESULTS: The 30-day readmission rates were 9.42 and 9.17% (derivation and validation cohorts, respectively). Age <65 years, male gender, first income quartile, African American race, race other than African American or Caucasian, Medicare, Medicaid, self-pay/no insurance, drug abuse, renal failure, chronic pulmonary disorder, diabetes, depression, and fluid and electrolyte disorder were associated with higher readmission risk after hospitalization for CHF. The RAHF scale was created and explained the 95% of readmission variability within the validation cohort. The RAHF scale was then used to define the following three levels of risk for readmission: low (RAHF score <12; 7.58% readmission rate), moderate (RAHF score 12-15; 9.78% readmission rate), and high (RAHF score >15; 12.04% readmission rate). The relative risk of readmission was 1.67 for the high-risk group compared with the low-risk group. CONCLUSION: The RAHF scale reliably predicts a patient's 30-day CHF readmission risk based on demographic and clinical factors present upon initial admission. By risk-stratifying patients, using models such as the RAHF scale, strategies tailored to each patient can be implemented to improve patient outcomes and reduce health care costs.

A Preoperative Scale for Determining Surgical Readmission Risk After Total Knee Arthroplasty.

BACKGROUND: Total knee arthroplasty (TKA) is one of the most common orthopaedic procedures performed in the U.S. The purpose of this study was to develop and verify a scale to preoperatively stratify a patient's risk of being readmitted to the hospital following a TKA. METHODS: Discharge data on 433,638 patients from New York and California (derivation cohort) and 269,934 patients from Florida and Washington (validation cohort) who underwent TKA were collected from the State Inpatient Database, a part of the Healthcare Cost and Utilization Project of the Agency for Healthcare Research and Quality (2006 to 2011). Demographic and clinical characteristics of patients were abstracted and analyzed to develop the Readmission After Total Knee Arthroplasty (RATKA) Scale. RESULTS: Overall 30-day readmission rates in the derivation and validation cohorts were 5.11% and 4.98%, respectively. The following factors were significantly associated with increased 30-day readmission rates in the derivation cohort: age of 41 to 50 years (odds ratio [OR] = 1.13), age of 71 to 80 years (OR = 1.21), age of 81 to 90 years (OR = 1.70), male sex (OR = 1.19), African-American race (OR = 1.37), "other" race/ethnicity (OR = 1.08), Medicaid payer (OR = 1.43), Medicare payer (OR = 1.27), anemia (OR = 1.19), chronic obstructive pulmonary disease (OR = 1.29), coagulopathy (OR = 1.22), congestive heart failure (OR = 1.64), diabetes (OR = 1.19), fluid and electrolyte disorder (OR = 1.25), hypertension (OR = 1.10), liver disease (OR = 1.27), renal failure (OR = 1.33), and rheumatoid arthritis (OR = 1.14). These factors were used to create the RATKA Scale. The RATKA score was then used to define 3 levels of risk for readmission: low (RATKA score of <13; 3.7% readmission rate), moderate (RATKA score of 13 to 16; 5.4% readmission rate), and high (RATKA score of >16; 7.6% readmission rate). The relative risk of readmission was 2.06 for the high-risk group compared with the low-risk group. CONCLUSIONS: The RATKA Scale derived from patient data from the derivation cohort was reliably able to explain readmission variability after TKA for patients in the validation cohort at a rate of >95%. Models such as the RATKA Scale will enable identification of the risk of readmission following TKA based on a patient's risk profile prior to surgery. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Readmission After COPD Exacerbation Scale: determining 30-day readmission risk for COPD patients.

BACKGROUND: COPD affects over 13 million Americans, and accounts for over half a million hospitalizations annually. The Hospital Readmission Reduction Program, established by the Affordable Care Act requires the Centers for Medicare and Medicaid Services to reduce payments to hospitals with excess readmissions for COPD as of 2015. This study sought to develop a predictive readmission scale to identify COPD patients at higher readmission risk. METHODS: Demographic and clinical data on 339,389 patients from New York and California (derivation cohort) and 258,113 patients from Washington and Florida (validation cohort) were abstracted from the State Inpatient Database (2006-2011), and the Readmission After COPD Exacerbation (RACE) Scale was developed to predict 30-day readmission risk. RESULTS: Thirty-day COPD readmission rates were 7.54% for the derivation cohort and 6.70% for the validation cohort. Factors including age 40-65 years (odds ratio [OR] 1.17; 95% CI, 1.12-1.21), male gender (OR 1.16; 95% CI, 1.13-1.19), African American (OR 1.11; 95% CI, 1.06-1.16), 1st income quartile (OR 1.10; 95% CI, 1.06-1.15), 2nd income quartile (OR 1.06; 95% CI, 1.02-1.10), Medicaid insured (OR 1.83; 95% CI, 1.73-1.93), Medicare insured (OR 1.45; 95% CI, 1.38-1.52), anemia (OR 1.05; 95% CI, 1.02-1.09), congestive heart failure (OR 1.06; 95% CI, 1.02-1.09), depression (OR 1.18; 95% CI, 1.14-1.23), drug abuse (OR 1.17; 95% CI, 1.09-1.25), and psychoses (OR 1.19; 95% CI, 1.13-1.25) were independently associated with increased readmission rates, P<0.01. When the devised RACE scale was applied to both cohorts together, it explained 92.3% of readmission variability. CONCLUSION: The RACE Scale reliably predicts an individual patient's 30-day COPD readmission risk based on specific factors present at initial admission. By identifying these patients at high risk of readmission with the RACE Scale, patient-specific readmission-reduction strategies can be implemented to improve patient care as well as reduce readmissions and health care expenditures.

Hoverboards: A new cause of pediatric morbidity.

INTRODUCTION: The hoverboard, a self-balancing powered scooter, was introduced to the market in 2015 and quickly became one of the most popular purchases of the year. As with similar products, this scooter brought a host of concerns surrounding injuries. The purpose of this study is to determine the incidence of injuries that coincided with the popularity of hoverboard. METHODS: The National Electronic Injury Surveillance System (NEISS) was queried from 2011 through 2015 for injuries related to scooters/skateboards, powered (product number, 5042), which includes the hoverboard. Patient data on sex, age, race, diagnosis, most severely injured body part, location where the injury occurred, and narrative of the injury were collected. The estimated injury incidence was calculated and compared on a yearly and monthly basis. Google Trends was used to determine the popularity of the hoverboard over the same time period. RESULTS: During the 5-year study period, there were an estimated 47,277 injuries associated with the hoverboard. In 2015, there was an average 208% (range, 167-278%; standard deviation (SD), 51.8%) increase in the number of injuries compared to any of the previous 4 years. Further analysis of these injuries revealed a significant increase in the number of forearm (475%; range, 310-662%; SD, 159%), leg (178%; range, 133-206%; SD, 34%), and head and neck (187%; range, 179-197%; SD, 7.6%) injuries in 2015 compared to the previous 4 years. The most common type of injury in 2015 was a fracture (38.9%). Analysis of the sites of these fractures between 2014 and 2015 revealed a 752% increase in forearm fractures, which included over a 4000% increase in the number of wrist fractures. CONCLUSIONS: Given the number of injuries caused by these products, safety equipment, such as wrist guards and helmets, should be worn in an attempt to reduce the number of injuries. Additionally, this study highlights the importance of physicians keeping up to date with current trends to best advise their patients on safe practices.

What is the Incidence of Suicide in Patients with Bone and Soft Tissue Cancer? : Suicide and Sarcoma.

BACKGROUND: Patients with cancer in the United States are estimated to have a suicide incidence that is approximately twice that of the general population. Patients with bone and soft tissue cancer often have physical impairments and activity limitations develop that reduce their quality of life, which may put them at high risk for depression, anxiety, and suicidal ideation. To our knowledge, there have been no large studies determining incidence of suicide among patients with bone and soft tissue cancer; this information might allow screening of certain high-risk groups. QUESTIONS/PURPOSES: To determine (1) the incidence of suicide in patients with bone and soft tissue cancer, (2) whether the incidence of suicide is greater in patients with bone and soft tissue cancer than it is in the general US population, and (3) any demographic and tumor characteristics associated with increased suicide incidence. METHODS: A retrospective analysis of the Surveillance, Epidemiology, and End Results (SEER) program was performed. A total of 23,620 patients with primary bone and soft tissue cancer were identified in this database from 1973 and 2013. Patients with a cause of death listed as "suicide and self-inflicted injury" were considered to have committed suicide and suicide incidences were determined for different demographic and tumor characteristics in this subset of patients. Patient data for age, gender, race, marital status, year of diagnosis, primary cancer site, cancer stage, course of treatment, and survival time were collected and analyzed. The incidence of suicide in patients with bone and soft tissue sarcoma was compared with the age-, gender-, and race-adjusted incidence of suicide in the general US population from 1970 to 2013 available from the National Center for Health Statistics through the SEER Program. RESULTS: The overall suicide incidence in this population was 32 per 100,000 person-years, which was higher than the age-, race-, and gender-adjusted US general population suicide incidence of 13 per 100,000 person-years. When compared with the incidence of suicide in matched subgroups of the general US population, a higher suicide incidence was observed in men (standardized mortality ratio [SMR], 2.49; 95% CI, 1.92-3.22; p < 0.001), patients of white race (SMR, 2.68; 95% CI, 1.94-3.56; p < 0.001), patients 21 to 30 years old (SMR, 4.40; 95% CI, 3.44-5.54; p < 0.001) and 61 to 70 years old (SMR, 3.27; 95% CI, 2.54-4.18; p < 0.001), patients with cancer of the vertebral column (SMR, 2.88; 95% CI, 2.13-3.83; p < 0.001) and pelvic bones (SMR, 2.75; 95% CI, 2.00-3.65; p < 0.001), and patients within the first 5 years of cancer diagnosis (SMR, 10.8; 95% CI, 9.19-12.61; p < 0.001). CONCLUSIONS: With identification of these characteristics that are associated with higher incidence of suicide, physicians should consider screening patients possessing these traits. By identifying at-risk patients, we can hope to reduce the incidence of suicide in this population by providing the treatment that these patients need. Further research must be done to determine how best to screen these patients and to identify the best interventions to reduce suicide incidence. LEVEL OF EVIDENCE: Level III, prognostic study.

A Preoperative Scale for Determining Surgical Readmission Risk After Total Hip Replacement.

IMPORTANCE: Total hip replacement is a commonly performed orthopedic procedure for the treatment of painful arthritis, osteonecrosis, or fracture. OBJECTIVE: To develop and verify a scale for predicting readmission rates for total hip replacement patients and allow for the development and implementation of readmission risk-reduction strategies. DESIGN, SETTING, AND PARTICIPANTS: Discharge data on 268 518 patients from New York and California (derivation cohort) and 153 560 patients from Florida and Washington (validation cohort) were collected from the State Inpatient Database, a part of the Healthcare Cost and Utilization Project of the Agency for Healthcare Research and Quality (2006-2011). Analysis of the derivation cohort was performed in July 2013 and analysis of the validation cohort was performed in August 2014. Demographic and clinical characteristics of patients undergoing total hip replacement were abstracted. The Readmission After Total Hip Replacement Risk Scale was developed to predict readmission risk. MAIN OUTCOME AND MEASURE: Readmission rate. RESULTS: Of the 268 518 patients from New York and California (derivation cohort), 151 009 (56.2%) were women and 216 477 (80.6%) were white. Of the 153 560 patients from Florida and Washington (validation cohort), 86 534 (56.3%) were women and 120 591 (78.5%) were white. Overall 30-day readmission rate was 5.89% for the derivation cohort and 5.82% for the validation cohort. Readmission rates for men and women were 5.79% and 6.08% for the derivation cohort (odds ratio [OR], 1.05; 95% CI, 1.02-1.09) and 5.80% and 5.84% for the validation cohort (OR, 0.99; 95% CI, 0.95-1.04), respectively. The following were all determined to be associated with increased risk of readmission after total hip replacement: being older than 71 years (OR, 1.83; 95% CI, 1.77-1.89), African American (OR, 1.23; 95% CI, 1.15-1.31), and in the lowest income quartile (OR, 1.18; 95% CI, 1.12-1.24); revision replacement (OR, 1.82, 95% CI, 1.75-1.90); liver disease (OR, 1.57; 95% CI, 1.39-1.77); congestive heart failure (OR, 1.49; 95% CI, 1.38-1.61); chronic pulmonary disease (OR, 1.33; 95% CI, 1.27-1.39); renal failure (OR, 1.26; 95% CI, 1.18-1.36); diabetes (OR, 1.21; 95% CI, 1.16-1.27); fluid and electrolyte disorder (OR, 1.21; 95% CI, 1.14-1.27); anemia (OR, 1.19; 95% CI, 1.15-1.25); rheumatoid arthritis (OR, 1.19; 95% CI, 1.10-1.29); coagulopathy (OR, 1.19; 95% CI, 1.08-1.32); hypertension (OR, 1.17; 95% CI, 1.12-1.21); and obesity (OR, 1.15; 95% CI 1.09-1.21). They were used to create the Readmission After Total Hip Replacement Risk Scale, which was applied to the validation cohort and explained 89.1% of readmission variability in that cohort. CONCLUSIONS AND RELEVANCE: Data derived from patients in the New York and California State Inpatient Database were reliably able to explain readmission variability for patients in the Florida and Washington State Inpatient Database at a rate of 89.1% based on known preoperative risk factors. Risk-stratification models, such as the Readmission After Total Hip Replacement Risk Scale, can identify high-risk patients for readmission and permit implementation of patient-specific readmission-reduction strategies to reduce readmissions and health care expenditures.