Anterior capsulectomy versus repair in direct anterior total hip arthroplasty.

BACKGROUND: Utilization of the direct anterior approach for total hip arthroplasty (DAA THA) has increased over the last ten years. The preservation and repair of the anterior hip capsule has been recommended, while anterior capsulectomy has been described by others. In contrast, the higher risk of posterior dislocation using the posterior approach improved significantly after capsular repair. No studies to date have investigated outcome scores based on capsular repair versus capsulectomy for the DAA. METHODS: Patients randomized to anterior capsulectomy or anterior capsule repair. Patients were blinded to their randomization. Maximum hip flexion was measured both radiographically and clinically with a goniometer. Using a one-sided t test assuming equal variance with an effect size, Cohen's d, of 0.6 and an alpha of 0.05, 36 patients in each group (total 72 patients) needed for a minimum 80% power. RESULTS: Median goniometer measurements preoperatively were 95° for repair (IQR 85-100) and 91° for capsulectomy (IQR 82-97.5) (p = 0.52). Four-month and one-year goniometer measurements also had no significant difference, 110° (IQR 105-120) and 110° (IQR 105-120) for repair and 105° (IQR 96-116) and 109° (IQR 102-120) for capsulectomy (p = 0.38 and p = 0.26). Median change in flexion as measured by goniometer at 4 months and one year was 12 and 9 degrees for repair and 9.5 and 3 degrees for capsulectomy (p = 0.53 and p = 0.46). X-ray analysis showed no differences in pre-op, 4-month, and one-year flexion with median one-year flexion of 105.5° (IQR 96-109.5) for repair and 100° (IQR 93.5-112) for capsulectomy (p = 0.35). VAS scores were the same for both groups at all three time points. HOOS scores improved equally for both groups. There are no differences in surgeon randomization, age, or gender. CONCLUSIONS: Both capsular repair and capsulectomy used in direct anterior approach THA result in equal maximum clinical as well as radiographic hip flexion with no change in postoperative pain or HOOS scores.

Inter-Rater Reliability of Clinical Testing for Laxity After Knee Arthroplasty.

BACKGROUND: The clinical examination for laxity has been considered a mainstay in evaluation of the painful knee arthroplasty, especially for the diagnosis of instability. More than 10 mm of anterior-posterior (AP) translation in flexion has been described as important in the diagnosis of flexion instability. The inter-observer reliability of varus/valgus and AP laxity testing has not been tested. METHODS: Ten subjects with prior to total knee arthroplasty (TKA) were examined by 4 fellowship-trained orthopedic knee arthroplasty surgeons. Each surgeon evaluated each subject in random order and was blinded to the results of the other surgeons. Each surgeon performed an anterior drawer test at 30 and 90 degrees of flexion and graded the instability as 0-5 mm, 5-10 mm or >10 mm. Varus-valgus testing was also graded. Motion capture was used during the examination to determine the joint position and estimate joint reaction force during the examination. RESULTS: Inter-rater reliability (IRR) was poor at 30 and 90 degrees for both the subjective rater score and the measured AP laxity in flexion (k = 018-0.22). Varus-valgus testing similarly had poor reliability. Force applied by the rater also had poor IRR. CONCLUSION: Clinical testing of knee laxity after TKA has poor reliability between surgeons using motion analysis. It is unclear if this is from differences in examiner technique or from differences in pain or quadriceps function of the subjects. Instability after TKA should not be diagnosed strictly by clinical testing and should involve a complete clinical assessment of the patient.

Narcotic Refills and Patient Satisfaction With Pain Control After Total Joint Arthroplasty.

BACKGROUND: Patient satisfaction has become an important metric for total joint arthroplasty (TJA) used to reimburse hospitals. Despite ubiquitous narcotic use for post-TJA pain control, there is little understanding regarding patient factors associated with obtaining opioid refills and associations with patient satisfaction. METHODS: Using our state's mandatory opioid prescription monitoring program, we reviewed preoperative and postoperative narcotic prescriptions filled for 438 consecutive TJA patients. Subjects were divided into 3 groups based on the number of post-TJA narcotic refills obtained (0, 1, or >1), and logistic regression analysis was conducted comparing demographics, surgical factors, and satisfaction with pain control. RESULTS: One hundred twenty-five patients (25.8%) did not consume preoperative opioids and received no postoperative refills. Total hip arthroplasty (THA) patients (P = .0004), subjects ≥65 years (P = .0057), and Medicare patients (P = .0058) had significantly higher rates of 0 postdischarge refills. THA recipients had 268% increased odds of not receiving a refill narcotic (adjusted odds ratio = 0.373; 95% confidence interval, 0.224- 0.622). Every 100-morphine milligram equivalent (MME) increase in presurgery use led to a 16% increase in odds of needing >1 opioid refill (adjusted odds ratio = 1.161; 95% confidence interval, 1.085-1.242). Subjects who noted higher satisfaction consumed less overall opioids when receiving a refill (436 vs 1119 MMEs, P = .021). CONCLUSION: Subjects who received fewer narcotic prescriptions and overall MMEs demonstrated higher rates of satisfaction with early pain control. Our results are consistent with other studies in showing that increased preoperative narcotic use portends higher rates of postoperative refills. There appears to be a subset of THA patients >65 years of age who may be candidates for opioid-sparing analgesia.

Dissociation of Acetabular Polyethylene Liners With a Morse Taper Design.

BACKGROUND: Polyethylene liner dissociation is an uncommon complication of hip replacement. Dissociation has been associated with particular acetabular component designs. This study reviewed acetabular liner dissociations in a specific modular cup with a Morse taper locking mechanism that has not been previously reported. METHODS: The senior author performed 655 primary total hip arthroplasties with one particular design of acetabular component using Class A polyethylene liners and metal head articulation. Cases with revision surgery performed for acetabular liner dissociation were reviewed. RESULTS: Seven of 655 patients with this cup underwent revision surgery for a dissociated liner. Liner dissociation occurred at a mean of 73 months postoperatively. Patients presented with new-onset hip pain or squeaking, 4 of which developed symptoms acutely. Two patients treated with polyethylene liner exchange into the same cup required a second revision surgery for recurrent dissociation. CONCLUSION: Polyethylene liner dissociation is an infrequent but possible complication associated with modular acetabular components using a Morse taper locking. Providers should be vigilant with long-term follow-up of patients with this acetabular system for patient complaints of catching or squeaking. Patients treated for liner dissociation should not have a new liner placed into the same acetabular shell given the risk for further dissociation.

Improvements in Isokinetic Quadriceps and Hamstring Strength Testing After Focused Therapy in Patients With Flexion Instability.

BACKGROUND: There is a paucity of literature to guide non-operative treatment for patients with problems after total knee arthroplasty (TKA). We sought to quantify how quadriceps and hamstring strength could improve with focused physical therapy (PT) and whether improving leg strength may prevent revision surgery for patients with flexion instability (FI) after TKA. METHODS: This retrospective study included patients diagnosed with FI by one of the 4 fellowship-trained arthroplasty surgeons at a single academic institution. Patients with FI were referred for strength measurements and a focused PT program. In total, 166 patients completed isokinetic testing to quantify their relative quadriceps and hamstring power, torque, and work measures compared to their contralateral leg. Fifty-five (33.5%) patients subsequently completed post-PT isokinetic testing. Statistical analysis was conducted to evaluate strength deficits in the knee with FI. RESULTS: Patients with FI were found to be 20.5%-38.4% weaker in all strength domains compared to the contralateral leg (P < .001). Patients who completed PT and pre-isokinetic and post-isokinetic testing demonstrated statistically significant gains in all extension metrics by a net range of 24.7%-34.2% (P = .011-.029) and their flexion strength metrics improved by 32.5%-40.2% (P = .002-.005). About 81.9% of patients in this subgroup did not undergo revision TKA. Those subjects who went on to revision did not statistically improve in any strength domain (P = .063-.121). CONCLUSION: Patients with FI after TKA have significantly weaker quadriceps and hamstrings in the operative compared to contralateral leg. Patients who did not undergo revision knee arthroplasty and completed a formal PT program improved quadriceps and hamstring strength by 30%. LEVEL OF EVIDENCE: IV (Case series).

The Rapid Response to the COVID-19 Pandemic by the Arthroplasty Divisions at Two Academic Referral Centers.

The COVID-19 pandemic has created widespread changes across all of health care. As a result, the impacts on the delivery of orthopedic services have been challenged. To ensure and provide adequate health care resources in terms of hospital capacity and personnel and personal protective equipment, service lines such as adult reconstruction and lower limb arthroplasty have stopped or substantially limited elective surgeries and have been forced to re-engineer care processes for a high volume of patients. Herein, we summarize the similar approaches by two arthroplasty divisions in high-volume academic referral centers in (1) the cessation of elective surgeries, (2) workforce restructuring, (3) phased delivery of outpatient and inpatient care, and (4) educational restructuring.

Streamlining Hospital Treatment of Prosthetic Joint Infection.

BACKGROUND: Prosthetic joint infection (PJI) is associated with significant morbidity, mortality, and costs. We developed a fast-track PJI care system using an infectious disease physician to work directly with the TJA service and coordinate in the treatment of PJI patients. We hypothesized that streamlined care of patients with hip and knee PJI decreases the length of the acute hospital stay without increasing the risk of complication or incorrect antibiotic selection. METHODS: A single-center retrospective chart review was performed for all patients treated operatively for PJI. A cohort of 78 fast-track patients was compared to 68 control patients treated before the implementation of the program. Hospital length of stay (LOS) and cases of antibiotic mismatch were primary outcomes. Secondary outcomes, including 90-day readmissions, reoperations, mortality, rate of reimplantation, and 12-month reimplant survival, were compared. Cox regressions were analyzed to assess the effects on LOS of patient demographics and the type of surgery performed. RESULTS: Average hospital LOS from infection surgery to discharge was significantly lower in the fast-track cohort (3.8 vs 5.7 days; P = .012). There were no episodes of antibiotic mismatch in the fast-track group vs 1 recorded episode in the control group. No significant differences were noted comparing 90-day complications, reimplantation rate, or 12-month reimplant survival rates. CONCLUSION: Through the utilization of an orthopedic-specific infectious disease physician, a fast-track PJI protocol can significantly shorten hospital LOS while remaining safe. Streamlining care pathways may help decrease the overall healthcare costs associated with treating PJI.

The Effect of the COVID-19 Pandemic on Electively Scheduled Hip and Knee Arthroplasty Patients in the United States.

BACKGROUND: In response to the COVID-19 pandemic, hospitals in the United States were recommended to stop performing elective procedures. This stoppage has led to the cancellation of a large number of hip and knee arthroplasties. The effect of this on patients' physical mental and economic health is unknown. METHODS: A survey was developed by the AAHKS Research Committee to assess pain, anxiety, physical function, and economic ability of patients to undergo a delayed operation. Six institutions conducted the survey to 360 patients who had to have elective hip and knee arthroplasty cancelled between March and July of 2020. RESULTS: Patients were most anxious about the uncertainty of when their operation could be rescheduled. Although 85% of patients understood and agreed with the public health measures to curb infections, almost 90% of patients plan to reschedule as soon as possible. Age and geographic region of the patients affected their anxiety. Younger patients were more likely to have financial concerns and concerns about job security. Patients in the Northeast were more concerned about catching COVID-19 during a future hospitalization. CONCLUSIONS: Patients suffering from the pain of hip and knee arthritis continue to struggle with pain from their end-stage disease. They have anxiety about the COVID-19 pandemic. Few patients feel they will be limited financially and 90% want to have surgery as soon as possible. Age and physical location of the patients affect their causes for anxiety around their future surgery.

After-Hours Calls in a Joint Replacement Practice.

BACKGROUND: Early discharge after joint arthroplasty requires additional resources to manage patients safely after surgery. Patient concerns must be addressed during nonbusiness hours to keep patients out of the emergency department and avoid readmissions. The goal of our study was to determine how type of system is utilized in a busy early discharge joint replacement practice. METHODS: In our total joint program, we have utilized a Google phone number to give patients access to a member of the surgical team after business hours and on weekends. The duration, chief complaint, and resolution of from the phone calls were collected prospectively for 3 months (July 3, 2017-October 3, 2017). RESULTS: Sixty-eight calls were received from 55 patients during the 3-month study period. Three hundred twenty-five cases were performed. The average duration of a call was 3.9 minutes. The average length of time from surgery to call was 17.5 days (range 0-442 days). Suboptimal health literacy was associated with increased calls within the first week after surgery (odds ratio = 4.1, 95% confidence interval = 1.2-14.5, P = .022). A chief complaint of pain was associated with primary versus revision surgery. (odds ratio = 3.23, 95% confidence interval = 1.08-9.86). DISCUSSION: An "after-hours" telephone contact service with a member of the surgical team may help avoid unnecessary emergency department visits. About one phone call was received per day, with an average duration of 3.9 minutes per call. These additional resources are necessary to maintain patient safety and satisfaction in early discharge joint replacement.

Rapid Recovery After Total Joint Arthroplasty Using General Anesthesia.

BACKGROUND: Multiple papers have purported the superiority of spinal anesthesia used in total joint arthroplasty (TJA). However, there is a paucity of data available for modern general anesthesia (GA) regimens used at high-volume joint replacement centers. METHODS: We retrospectively reviewed a series of 1527 consecutive primary TJAs (644 total hip arthroplasties and 883 total knee arthroplasties) performed over a 3-year span at a single institution that uses a contemporary GA protocol and report on the length of stay, early recovery rates, perioperative complications, and readmissions. RESULTS: From the elective TJAs performed using a modern GA protocol, 96.3% (n = 1471) of patients discharged on postoperative day 1, and 97.2% (n = 1482) of subjects were able to participate with physical therapy on the day of surgery. Only 6 patients (0.4%) required an intensive care unit stay postoperatively. The 90-day readmission rate over this time was 2.4% (n = 36), while the reoperation rate was 1.3% (n = 20). DISCUSSION: Neuraxial anesthesia for TJA is commonly preferred in high-volume institutions utilizing contemporary enhanced recovery pathways. Our data support the notion that the utilization of modern GA techniques that limit narcotics and certain inhalants can be successfully used in short-stay primary total joint arthroplasty. LEVEL OF EVIDENCE: IV- Case series.

Cost Analysis and Bundled Care of Hip and Knee Replacement.

Financial success in a bundled payment system requires knowledge of the costs of care throughout the period of risk. Understanding the significant cost-drivers of total joint arthroplasty (TJA) is crucial in this effort. This article inspects the basics of reimbursement under Medicare's bundled care programs as well as some common investigative tools used in the literature to measure cost. Additionally, the effects of standardized enhanced recovery clinical pathways on costs are reviewed. Finally, drivers of implant costs and several proven measures for implant cost-reduction are evaluated. This review provides surgeons and hospitals successful measures to reduce the cost of TJA via enhanced recovery pathways and reduced implant pricing. (Journal of Surgical Orthopaedic Advances 28(4):241-249, 2019).

New Failure Mechanism of Acetabular Constrained Liner: A Case Report.

Implant dislocation following total hip arthroplasty, particularly revision arthroplasty, remains a common postoperative complication. Constrained acetabular liners provide surgeons with an implant option that provides resistance to dislocation forces. These added forces, however, are transmitted to the implant materials and to the bone\endash implant interface, resulting in unique failure mechanisms. This case report presents two cases highlighting a previously unreported mechanism of failure of the Depuy Pinnacle ES constrained liner encountered during intraoperative implantation of the components (Journal of Surgical Orthopaedic Advances 28(1):68-73, 2019).

Is Rapid Recovery Hip and Knee Replacement Possible and Safe in the Octogenarian Patient?

BACKGROUND: Rapid recovery programs are now aimed to reduce costs of hip and knee arthroplasties by discharging patients directly home, shortening hospital length of stay (LOS), and reducing readmission rates. Although patients aged 80 years and older are included in the Medicare bundle, little work has been performed to determine if older patients can safely participate in rapid recovery programs. METHODS: We retrospectively reviewed 2482 patients undergoing primary and revision total hip and knee arthroplasties (THA and TKA) who all participated in a multifaceted rapid recovery program. The goals of this program were next day discharge to home without the use of home services or post-acute care admission. We examined the hospital LOS and the percentage of patients discharged home as well as 90-day readmission rates to determine efficacy and safety of this program in the patients aged 80 years and older. RESULTS: Octogenarians receiving primary THA and TKA were discharged home >90% of the time with LOSs <2 days and low readmission rates. Revision THA and TKA patients aged 80 years and older were discharged home about 70% of the time with significantly longer LOSs than patients aged more than 80 years. The revision THA patients aged more than 80 years had the highest readmission rates. CONCLUSION: Patients aged more than 80 years can successfully and safely participate in rapid recovery programs.

Choices, Compromises, and Controversies in Total Knee and Total Hip Arthroplasty Modifiable Risk Factors: What You Need to Know.

BACKGROUND: Total joint arthroplasty has historically been very successful for most patients, yet some still incur a complication. In an era of value-based care, certain efforts need to be taken to optimize patients' risk profile before surgery to decrease the chances of readmission or surgical complication. METHODS: We reviewed 10 key medical conditions and lifestyle factors that surgeons should improve before pursuing total joint arthroplasty and provide a summary of the available literature to guide certain optimization thresholds. RESULTS: With careful attention to and the creation of a preoperative checklist, surgeons can identify key domains, including morbid obesity, malnutrition, diabetes, smoking, opioid use, poor dentition, cardiovascular disease, preoperative anemia, staphylococcus colonization, and psychological disorders and intervene based on an individual's areas of deficiencies. CONCLUSION: By following stringent protocols and rescheduling surgery until optimization has occurred, we can work to provide patients the best chance for a successful outcome with an elective hip or knee arthroplasty.

Patients With Hip or Knee Arthritis Underreport Narcotic Usage.

BACKGROUND: Patients taking narcotics chronically are more likely to have worse outcomes after total joint arthroplasty. These negative outcomes may be avoided when modifiable risk factors such as narcotic use are identified and improved before elective joint replacement. An accurate assessment of narcotic use is needed to identify patients before surgery. This study examines the amount of reported narcotic use in patients with hip or knee osteoarthritis and compares this with the narcotic prescriptions recorded in our state's drug prescription monitoring database. METHODS: All new patients seen during a 1-year period by our adult reconstruction practice were identified. Patients' electronic health records were reviewed to determine whether narcotic use was reported. A subsequent search was performed using the Arkansas Prescription Drug Monitoring Program to determine if the patient had been previously prescribed a narcotic. RESULTS: A total of 502 patients were included in the study. One hundred seventy patients (34%) were prescribed a narcotic within 3 months of the clinic visit according to the Arkansas Prescription Drug Monitoring Program, but only 111 (22%) reported narcotic use in their electronic health record (P < .0001). Moreover, only 92 patients (54% of 170) prescribed a narcotic within 3 months reported it. Narcotic recipients were more likely to be under the age of 65 years (P = .0081), smokers (P < .0001), and current benzodiazepine users (P < .0001). CONCLUSION: This study demonstrates that patients significantly underreport their narcotic use to their physician. The availability of a state prescription drug monitoring program allows physicians to check the frequency of filled narcotic prescriptions by their patients.

Preoperative Smoking and Narcotic, Benzodiazepine, and Tramadol Use are Risk Factors for Narcotic Use After Hip and Knee Arthroplasty.

BACKGROUND: The use of narcotics has been found to be a modifiable risk factor for success of arthroplasty. We sought to determine the risk factors leading to increased narcotic use after total hip arthroplasty and total knee arthroplasty. METHODS: A retrospective chart review was performed on new patients presenting to an orthopedic reconstructive-service clinic. New patients aged 18 years or older with osteoarthritis of the hip or knee who presented over a 1-year period and underwent total knee arthroplasty or total hip arthroplasty were included. The Arkansas prescription monitoring program was then used to determine recent narcotic and benzodiazepine prescriptions filled within 3 months of surgery, and this was converted into morphine milligram equivalents (MME). RESULTS: One hundred seventy-nine patients met the inclusion criteria. When compared with patients who did not take any preoperative opioids, narcotic- and tramadol-only users filled an average of 86% and 38% more MME, respectively. Benzodiazepine users required an average of 81% more MME postoperative than nonusers, and smokers required an average of 90% more MME postoperative than nonsmokers. Subjects with body mass index >40 kg/m2 had 82% higher average postoperative MME than subjects with body mass index <25 kg/m2. Age and sex had no significant correlation with postoperative narcotic use. CONCLUSION: This study suggests that a patient's preoperative narcotic, tramadol, benzodiazepine, and tobacco use are correlated to the amount of postoperative narcotic prescriptions filled in the 3 months following surgery. Predisposition to substance abuse may be a characteristic which leads to increased postoperative narcotic use.

Effect of Risk Acceptance for Bundled Care Payments on Clinical Outcomes in a High-Volume Total Joint Arthroplasty Practice After Implementation of a Standardized Clinical Pathway.

BACKGROUND: The Bundled Payments for Care Improvement (BPCI) initiative and the Arkansas Payment Improvement (API) initiative seek to incentivize reduced costs and improved outcomes compared with the previous fee-for-service model. Before participation, our practice initiated a standardized clinical pathway (CP) to reduce length of stay (LOS), readmissions, and discharge to postacute care facilities. METHODS: This practice implemented a standardized CP focused on patient education, managing patient expectations, and maximizing cost outcomes. We retrospectively reviewed all primary total joint arthroplasty patients during the initial 2-year "at risk" period for both BPCI and API and determined discharge disposition, LOS, and readmission rate. RESULTS: During the "at risk" period, the average LOS decreased in our total joint arthroplasty patients and our patients discharged home >94%. Patients within the BPCI group had a decreased discharge to home and decreased readmission rates after total hip arthroplasty, but also tended to be older than both API and nonbundled payment patients. CONCLUSION: While participating in the BPCI and API, continued use of a standardized CP in a high-performing, high-volume total joint practice resulted in maintenance of a low-average LOS. In addition, BPCI patients had similar outcomes after total knee arthroplasty, but had decreased rates of discharge to home and readmission after total hip arthroplasty.

BPCI: Everyone Wins, Including the Patient.

BACKGROUND: Alternative payment models are becoming increasingly more common with the rising cost of the US health care. Bundled payment programs for elective hip and knee arthroplasty have shown promising results by improved outcomes and significant cost reduction. METHODS: All consecutive total joint arthroplasty with diagnosis-related group (DRG) 469/470 were included in this study. And 1427 episodes from 2009 to 2012 were defined as the baseline group; 461 episodes from October 2013 to September 2014 were defined as the Bundled Payments for Care Improvement (BPCI) group. RESULTS: BPCI group had a 14% reduction in cost per episode. The average length of stay decreased from 3.81 to 2.57 days. All-cause readmissions within 90 days of surgery decreased from 16% to 10%. The average cost of readmission decreased by 23%. Net Centers for Medicare and Medicaid Services (CMS) reconciliation payment for BPCI initiative participation was $1,012,962.79 for this 12-month study. CONCLUSION: Our participation in the 2013-2014 CMS BPCI initiative for DRG 469/470 led to decreased readmissions and significant cost savings. In this study, minimizing hospital length of stay and discharging patients to home were the most effective strategies to achieve these outcomes.

Modifiable Risk Factors Are Common in Early Revision Hip and Knee Arthroplasty.

BACKGROUND: Obesity, smoking, uncontrolled diabetes, and poor dental health are modifiable risk factors for revision total joint arthroplasty. To protect patients from revision surgery while also reducing cost, some joint arthroplasty practices use these conditions as contraindications until they are improved. However, this practice is variable among joint arthroplasty surgeons. We hypothesize that a relatively high rate of revision arthroplasty patients had modifiable risk factors at the time of primary surgery. METHODS: A retrospective review of all revision total hip and knee arthroplasties performed at an academic, tertiary referral center within 2 years of primary surgery was conducted. The presence of body mass index >40, hemoglobin A1c >8, poor dentition, and smoking status were obtained from the electronic medical record. Risk factors were described and compared between infected revisions and noninfected revisions. RESULTS: A total of 128 revision arthroplasties were performed at our institution in one year. And 23 of 57 (40.4%) total hip revision and 31 of 71 (43.7%) total knee revision patients had at least 1 modifiable risk factor. Infected hip revision patients were more likely to have increased body mass index compared to noninfected patients. Infected knee revision patients were more likely to smoke, have poor dentition, and have >1 contraindication compared to noninfected patients. CONCLUSION: A high percentage of patients undergoing early revision arthroplasty had at least 1 modifiable risk factor for a primary joint arthroplasty. Joint arthroplasty surgeons may help reduce revision surgery through counseling and appropriate referral for modification of risk factors.

A Perioperative Patient Support System Was Unable to Mitigate the Risk of Hospital Readmission for Total Hip Arthroplasty Patients With High American Society of Anesthesiologists Grades.

BACKGROUND: Utilization of a patient support system including a patient "navigator" to maintain patient engagement upon discharge home has successfully reduced the number of hospital readmissions after arthroplasty procedures. Although successful in a general patient population, the ability of the support system to reduce readmissions in subsets of "high-risk" patients has not been evaluated. METHODS: We identified 878 primary total hip arthroplasties (THAs) performed at a single institution between 2013 and 2015. A binary regression was used to determine if a model of patient factors could accurately predict readmission, and the individual effects of each factor on readmissions were assessed. RESULTS: No combination of patient factors was able to accurately predict the need for hospital readmission. However, those with American Society of Anesthesiologists (ASA) grades 3 or 4 (32/375 [8.8%]) were twice as likely to be readmitted than those with ASA grades 1 or 2 (23/503 [4.4%], P = .02; odds ratio = 2.0 [95% CI = 1.2-3.6], P = .01). CONCLUSION: Maintaining routine communication with the patient and surgeon's office throughout the postoperative period successfully reduced readmission rates for those with low ASA grades; however, implementing this program did not lessen the risk of readmission for patients with greater comorbidity burdens. Future studies are necessary to determine if interventions to medically optimize patients with high ASA grades can reduce readmission rates, but until such time, risk adjustment methodologies are necessary to avoid financial penalties for readmissions for high-ASA grade patients that have been repeatedly demonstrated to be at an inherently increased risk.