Do You PROMIS (Patient Reported Outcomes Measurement Information System)? Physical Function and Pain Interference Scores After Total Knee and Hip Arthroplasty

Background

Physical function and pain outcomes vary after arthroplasty. We investigated differences in postoperative Patient-Reported Outcomes Measurement Information System (PROMIS) physical function (PF) and pain interference (PI) scores for patients undergoing total knee arthroplasty (TKA) and total hip arthroplasty (THA). We aimed to identify preoperative factors that predict postoperative PROMIS scores.

Methods

Patients who underwent TKA and THA from 2014-2020 were eligible. Preoperative variables including demographics, comorbidities, and pain scores were obtained from the medical record. Patients completed surveys measuring postoperative PF and PI. Descriptive statistics and separate linear regression models for each anatomical location were performed to examine factors predicting postoperative PROMIS PF and PI scores.

Results

Surveys were completed by 2411 patients (19.5% response rate). Unadjusted mean PF postoperative scores were 47.2 for TKA and 48.8 for THA. Preoperative predictors of lower PF included female sex; body mass index and comorbidities for TKA and THA; and age, tobacco use, and non-White race for THA. Mean PI scores were 47.9 for THA and 49.0 for TKA. Preoperative predictors of increased PI included non-White race and increased body mass index for TKA and THA; higher preoperative pain for TKA; and female sex and increased comorbidity for THA.

Conclusions

Postoperative PROMIS scores were similar for TKA and THA, with THA having slightly higher PF and lower PI scores. Regression models using preoperative variables showed similar performance for TKA compared with THA. These findings suggest areas for future development of clinical decision support tools.

Is primary total hip arthroplasty in patients with Down's syndrome associated with increased complications at 2 years follow-up?

INTRODUCTION

Previous reports on primary total hip arthroplasty (THA) in patients with Down's syndrome (DS) are often small and/or lack a comparison cohort, and thus it is challenging to draw meaningful conclusions about this group. The purpose of this study was to report on the post-operative complications in patients with DS undergoing primary THA, compared to a non-DS cohort.

METHODS

In this retrospective study, we evaluated patients from 2010 to 2018 using a national database. We assessed surgical complications: closed reduction for dislocation, revision, resection, periprosthetic fracture, and infection in patients with a diagnosis of DS undergoing primary THA and compared them to a THA group of patients without DS. Patients undergoing THA for hip fractures were excluded. Complications were evaluated at 90 days and 2 years. Multivariable logistic regression analysis was used to adjust for age, sex, body mass index, and Charlson comorbidity index.

RESULTS

At 90 days patients with DS had an increased risk of revision (OR 3.1, CI 1.14-8.41), but no significant risk of resection (OR 5.24, CI 0.73-37.8), closed reduction (OR 2.03, CI 0.28-14.59), infection (OR 1.48, CI 0.6-3.62), or periprosthetic fracture (OR 1.97, CI 0.27-14.14). At 2 years patients with DS had an increased risk of periprosthetic fracture (OR 5.88, CI 1.84-18.78), but no significant increased risk of revision (OR 1.82, CI 0.66-5.01), resection (OR 2.37, CI 0.33-17.17), or infection (OR 0.65, CI 0.2-2.07).

CONCLUSIONS

Primary THA in patients with DS is associated with increased 90-day revision, and periprosthetic fracture at 2 years.

Chronic Pain Prevalence and Factors Associated With High Impact Chronic Pain following Total Joint Arthroplasty: An Observational Study

Hip, knee, and shoulder arthroplasty are among the most frequently performed orthopaedic procedures in the United States. High impact and bothersome chronic pain rates following total joint arthroplasty (TJA) are unknown; as are factors that predict these chronic pain outcomes. This retrospective observational study included individuals that had a TJA from January 2014 to January 2020 (n = 2,638). Pre-operative and clinical encounter information was extracted from the electronic health record and chronic pain state was determined by email survey. Predictor variables included TJA location, number of surgeries, comorbidities, tobacco use, BMI, and pre-operative pain intensity. Primary outcomes were high impact and bothersome chronic pain. Rates of high impact pain (95% CI) were comparable for knee (9.8-13.3%), hip (8.3-11.8%) and shoulder (7.6-16.3%). Increased risk of high impact pain included non-white race, two or more comorbidities, age less than 65 years, pre-operative pain scores 5/10 or higher, knee arthroplasty, and post-operative survey completion 24 months or less. Rates of bothersome chronic pain (95% CI) were also comparable for knee (24.9-29.9%) and hip (21.3-26.3%) arthroplasty; but higher for shoulder (26.9-39.6%). Increased risk of bothersome chronic pain included non-white race, shoulder arthroplasty, knee arthroplasty, current or past tobacco use, and being female. PERSPECTIVE: In this cohort more than 1/3rd of individuals reported high impact or bothersome chronic pain following TJA. Non-white race and knee arthroplasty were the only two variables associated with both chronic pain outcomes.

Perioperative Selective Serotonin Reuptake Inhibitor Use Is Associated With an Increased Risk of Transfusion in Total Hip and Knee Arthroplasty

BACKGROUND

Selective serotonin reuptake inhibitors (SSRIs) have been shown in both orthopedic and general surgery literature to be associated with an increased risk of blood loss, and this is thought to occur via diminished platelet serotonin reuptake and subsequent decline in platelet aggregation potential. In this study, we aim at quantifying the effect of treatment with SSRIs on blood loss and transfusion rates following total hip (THA) or total knee arthroplasty (TKA).

METHODS

THA (4485) and TKA (5584) cases from January 2013 to December 2017 at the investigating institution were queried and analyzed separately from an institutional database. Patients were stratified by utilization of an SSRI at the time of surgery. Patient demographics, baseline coagulopathy, preoperative and postoperative hemoglobin, transfusion, and length of stay were obtained to compare the 2 cohorts.

RESULTS

The transfusion rate for SSRI users was 3.9% in the TKA group and 8.5% in the THA group. After controlling for age, gender, body mass index, presence of coagulopathy, procedure (THA vs TKA), and SSRI status, SSRI utilization was significantly associated with increased blood loss (P < .004), and logistic regression controlling for the same variables showed SSRI utilization to be predictive of transfusion (odds ratio, 1.476; P < .001).

CONCLUSION

SSRI utilization was associated with increased perioperative blood loss and predictive of transfusion risk, particularly with THA. This represents an important factor that may be modified in the setting of total joint arthroplasty but further work will be necessary to study potential alternative medications for depression in the perioperative phase.

Tranexamic acid or epsilon-aminocaproic acid in total joint arthroplasty? A randomized controlled trial

AIMS

Antifibrinolytic agents, including tranexamic acid (TXA) and epsilon-aminocaproic acid (EACA), have been shown to be safe and effective for decreasing perioperative blood loss and transfusion following total hip arthroplasty (THA) and total knee arthroplasty (TKA). However, there are few prospective studies that directly compare these agents. The purpose of this study was to compare the benefits of intraoperative intravenous TXA with EACA.

PATIENTS AND METHODS

A total of 235 patients (90 THA and 145 TKA) were enrolled in this prospective, randomized controlled trial at a single tertiary-care referral centre. In the THA cohort, 53.3% of the patients were female with a median age of 59.8 years (interquartile range (IQR) 53.3 to 68.1). In the TKA cohort, 63.4% of the patients were female with a median age of 65.1 years (IQR 59.4 to 69.5). Patients received either TXA (n = 119) or EACA (n = 116) in two doses intraoperatively. The primary outcome measures included change in haemoglobin level and blood volume, postoperative drainage, and rate of transfusion. Secondary outcome measures included postoperative complications, cost, and length of stay (LOS).

RESULTS

TKA patients who received EACA had greater drainage (median 320 ml (IQR 185 to 420) vs 158 ml (IQR 110 to 238); p < 0.001), increased loss of blood volume (891 ml (IQR 612 to 1203) vs 661 ml (IQR 514 to 980); p = 0.014), and increased haemoglobin change from the preoperative level (2.1 ml (IQR 1.7 to 2.8) vs 1.9 ml (IQR 1.2 to 2.4); p = 0.016) compared with patients who received TXA. For the THA cohort, no statistically significant differences were observed in any haematological outcome measure. One patient in the EACA group required transfusion. No patient in the TXA group required transfusion. There were no statistically significant differences in number or type of postoperative complications or LOS for either THA or TKA patients regardless of whether they received TXA or EACA.

CONCLUSION

For hip and knee arthroplasty procedures, EACA is associated with increased perioperative blood loss compared with TXA. However, there is no significant difference in transfusion rate. While further prospective studies are needed to compare the efficacy of each agent, we currently recommend orthopaedic surgeons to select their antifibrinolytic based on cost and regional availability. Cite this article: Bone Joint J 2019;101-B:1093-1099.

Donning Gloves Before Surgical Gown Eliminates Sleeve Contamination

BACKGROUND

There are numerous studies in the literature that have recognized the importance of the glove-gown interface as a potential source of intraoperative bacterial contamination. It has been demonstrated that the methods with which one dons their surgical gown and gloves can alter the level of gown contamination. We hypothesize that donning undergloves before the surgical gown will decrease if not eliminate sleeve contamination.

METHODS

We performed a comparative study to assess the differences in gown contamination between three different gown and glove donning techniques. Participants ranged in experience level from intern to attending. Each participant covered their hands with ultraviolet light disclosing lotion and then donned surgical gown and gloves with their preferred technique and with the proposed technique in a randomly assigned order. The gowns were then removed and analyzed under ultraviolet light for distance and quantity of sleeve contamination.

RESULTS

The gloves-first technique demonstrated zero contamination in all samples. This is significantly less than both closed and open staff-assisted techniques (P < .0001). All samples of closed and open techniques demonstrated some level of contamination. The distance of contamination on the right sleeve is significantly greater than the left sleeve (P < .0001).

DISCUSSION

The gloves-first technique demonstrates zero sleeve contamination throughout all samples, regardless of the experience level. We strongly recommend considering the use of this glove and gown donning technique as opposed to the currently accepted closed and open techniques in an effort to reduce gown contamination.

The Impact of Electronic Medical Record Implementation on Labor Cost and Productivity at an Outpatient Orthopaedic Clinic

BACKGROUND

Widespread adoption of electronic medical record (EMR) systems is increasing. EMR implementation can be costly and typically requires workflow redesign. To our knowledge, no studies to date have examined the impact of EMR implementation using advanced cost accounting methods or the impact of its implementation on orthopaedic surgeons in an outpatient setting.

METHODS

Time-driven activity-based costing (TD-ABC) was used to evaluate the effect of EMR implementation in an outpatient adult reconstruction clinic. One hundred and forty-three patients were prospectively timed throughout their visit to clinics, before implementation of a hospital system-wide EMR system and then again 2 months, 6 months, and 2 years after implementation. Data were analyzed to investigate the effects of EMR implementation on labor cost and provider time.

RESULTS

Total labor costs per patient visit significantly increased at 2 months after EMR implementation (from $36.88 to $46.04; p = 0.05). Drivers of this change included increases in the amount of time that attending surgeons spent per patient (from 9.38 to 10.97 minutes, with the cost increasing from $21.10 to $27.01), as well as increased time that certified medical assistants spent assessing patients (from 3.4 to 9.1 minutes; p < 0.001). Two months after EMR implementation, providers were spending more than twice as long documenting patient encounters (7.6 compared with 3.3 minutes; p < 0.001). However, by 6 months after implementation, total labor costs were similar to those before implementation ($38.75 compared with $36.88; p = 0.689) and they remained similar at 2 years after implementation ($36.88 compared with $37.73; p = 0.84). After the initial learning period following EMR implementation, providers spent more time documenting encounters (8.43 compared with 3.28 minutes; p < 0.001) but less time interacting with patients (10.03 compared with 14.65 minutes; p = 0.013).

CONCLUSIONS

Using TD-ABC, we observed the EMR implementation learning period, returning to pre-introduction efficiency at 6 months. Cost increases because of increased certified medical assistant time spent with patients and physician time on documentation were offset by less patient-physician interaction. Health-care systems and policymakers should be aware that the length of the implementation period is approximately 6 months and that implementation may alter the time that providers spend with patients.

CLINICAL RELEVANCE

This article offers insight into the impact of EMR implementation on the orthopaedic surgeon's clinic efficiency and workflows.

The Utility of Basic Metabolic Panel Tests After Total Joint Arthroplasty

INTRODUCTION

Routine laboratory studies are often obtained daily after total joint arthroplasty (TJA) regardless of medical management. The purpose of this study was to investigate the utility of routine basic metabolic panel (BMP) tests after TJA. Furthermore, the goal was to identify factors that may predispose patients to abnormal laboratory values that require medical intervention.

METHODS

A retrospective review was performed on 767 patients who underwent primary TJA at a single institution. Preoperative and postoperative potassium, sodium, creatinine, and glucose values were collected along with demographic data, comorbidities, and procedural characteristics. Multivariable logistic regression models were used to determine independent risk factors for abnormal postoperative laboratory values.

RESULTS

Diabetes was associated with abnormal glucose (odds ratio [OR] 23.4, 95% confidence interval [CI] 10.7-51.0, P < .001), while chronic kidney disease was associated with abnormal creatinine (OR 3.1, 95% CI 1.7-5.8, P < .001) and potassium (OR 1.8, 95% CI 1.1-2.8, P = .014) requiring medical intervention. An abnormal preoperative laboratory value was also associated with medical treatment for each of sodium, potassium, and creatinine (all P < .001). Average number of BMP tests collected for patients who did not receive medical intervention was 2.8. This equated to $472,372.56 in total hospital charges.

CONCLUSION

Cost containment while maintaining high-quality patient care is critical. Routine postoperative BMP tests in patients with normal preoperative values without major medical comorbidities do not contribute to actionable information. Patients with diabetes, chronic kidney disease, or with abnormal preoperative values should obtain a BMP after TJA.

Dual Diagnosis and Total Hip Arthroplasty

The co-occurrence of a mental illness and a substance abuse disorder (SUD) is common and has been referred to as a "dual diagnosis" (DD). Although studies have independently investigated mental illness alone and SUD alone, few have examined the effects of these entities combined on complications. A search of the Medicare database from 2005 to 2012 identified 2000 DD patients who underwent total hip arthroplasty (THA). They were compared with 86,976 patients with mental illness only and 590,689 controls (no mental illness or SUD). Medical comorbidities and postoperative complications at 30-day, 90-day, and minimum 2-year time points were analyzed. There was a significant increase (P<.001) in 7 (53.8%) of 13 recorded postoperative medical complications, including acute renal failure (odds ratio [OR], 1.78), postoperative anemia (OR, 1.31), and blood transfusion (OR, 1.24), at the 90-day time point. In addition, there was a statistically significant increase overall in periprosthetic infection (periprosthetic joint infection OR, 4.30; P<.001), periprosthetic fracture (OR, 2.80; P<.001), dislocation (OR, 6.38; P<.001), and the need for THA revision (OR, 3.58; P<.001). When compared with patients with mental illness only, DD patients remained at significantly (P<.001) increased risk for 90-day and overall postoperative surgical complications, including dislocation, periprosthetic joint infection, and THA revision. Patients with a DD were at significant risk for perioperative complications compared with both control patients and patients with mental illness only. Studies investigating only psychiatric disease or only SUD may miss a vulnerable cohort. Further investigation is needed to exactly define to what extent DD amplifies complication rates. [Orthopedics. 2018; 41(3):e321-e327.].

Ankylosing Spondylitis Increases Perioperative and Postoperative Complications After Total Hip Arthroplasty

BACKGROUND

Ankylosing spondylitis (AS) is a chronic autoimmune spondyloarthropathy that primarily affects the axial spine and hips. Progressive disease leads to pronounced spinal kyphosis, positive sagittal balance, and altered biomechanics. The purpose of this study is to determine the complication profile of patients with AS undergoing total hip arthroplasty (THA).

METHODS

The Medicare sample was searched from 2005 to 2012 yielding 1006 patients with AS who subsequently underwent THA. Risk ratios (RRs) with 95% confidence intervals (CIs) were calculated for 90-day, 2-year, and the final postoperative follow-up for complications including hip dislocation, periprosthetic fracture, wound complication, revision THA, and postoperative infection.

RESULTS

Compared to controls, AS patients had an RR of 2.50 (CI, 1.04-5.99) of THA component breakage at 90-days post-operatively and 1.99 (CI, 1.10-3.59) at 2-years. The RR of periprosthetic hip dislocation was elevated at 90 days (1.44; CI, 0.93-2.22) and significantly increased at 2-years (1.67; CI, 1.25-2.23) and overall follow-up (1.49; CI, 1.14-1.93). Similarly, the RR for THA revision was elevated at 90-days (1.46; CI, 0.97-2.18) and significantly increased at 2-years (1.69; CI, 1.33-2.14) and overall follow-up (1.51; CI, 1.23-1.85).

CONCLUSION

Patients with AS are at increased risk for complications after THA. Altered biomechanics from a rigid, kyphotic spine place increased demand on the hip joints. The elevated perioperative and postoperative risks should be discussed preoperatively, and these patients may require increased preoperative medical optimization as well as possible changes in component selection and position to compensate for altered spinopelvic biomechanics.

Analysis of complication rates following perioperative transfusion in shoulder arthroplasty

BACKGROUND

Postoperative anemia requiring a blood transfusion is not uncommon following anatomic total shoulder arthroplasty (TSA) or reverse total shoulder arthroplasty (RTSA). However, the potential complications in patients undergoing transfusion after shoulder arthroplasty remain unclear. The goal of this study was to examine the postoperative outcomes of patients receiving blood transfusions following TSA and RTSA.

METHODS

Using the Medicare Standard Analytic Files database, we identified all patients undergoing TSA or RTSA between 2005 and 2010. Using International Classification of Diseases, Ninth Revision, Clinical Modification and Current Procedural Terminology codes, we identified the procedure, transfusion status, comorbidities, and postoperative complications of interest. Odds ratios and 95% confidence intervals were calculated.

RESULTS

We identified 7,794 patients who received a perioperative blood transfusion following TSA or RTSA, as well as 34,293 age- and gender-matched controls, during the study period. Patients who received a perioperative transfusion had statistically significantly higher rates of myocardial infarction, pneumonia, systemic inflammatory response syndrome or sepsis, venous thromboembolic events, and cerebrovascular accidents at all time points in question. Patients who received a blood transfusion also showed an increased incidence of surgical complications, including periprosthetic infection and mechanical complications, up to 2 years postoperatively.

CONCLUSION

To our knowledge, this represents the largest study to examine the relationship between the need for perioperative blood transfusion and postoperative medical and surgical outcomes following TSA and RTSA. The results observed in this study highlight the importance of preoperative counseling and medical optimization prior to shoulder arthroplasty, particularly in patients with preoperative anemia or multiple medical comorbidities.

The Impact of Lumbar Spine Disease and Deformity on Total Hip Arthroplasty Outcomes

Concomitant spine and hip disease in patients undergoing total hip arthroplasty (THA) presents a management challenge. Degenerative lumbar spine conditions are known to decrease lumbar lordosis and limit lumbar flexion and extension, leading to altered pelvic mechanics and increased demand for hip motion. In this study, the effect of lumbar spine disease on complications after primary THA was assessed. The Medicare database was searched from 2005 to 2012 using International Classification of Diseases, Ninth Revision, procedure codes for primary THA and diagnosis codes for preoperative diagnoses of lumbosacral spondylosis, lumbar disk herniation, acquired spondylolisthesis, and degenerative disk disease. The control group consisted of all patients without a lumbar spine diagnosis who underwent THA. The risk ratios for prosthetic hip dislocation, revision THA, periprosthetic fracture, and infection were significantly higher for all 4 lumbar diseases at all time points relative to controls. The average complication risk ratios at 90 days were 1.59 for lumbosacral spondylosis, 1.62 for disk herniation, 1.65 for spondylolisthesis, and 1.53 for degenerative disk disease. The average complication risk ratios at 2 years were 1.66 for lumbosacral spondylosis, 1.73 for disk herniation, 1.65 for spondylolisthesis, and 1.59 for degenerative disk disease. Prosthetic hip dislocation was the most common complication at 2 years in all 4 spinal disease cohorts, with risk ratios ranging from 1.76 to 2.00. This study shows a significant increase in the risk of complications following THA in patients with lumbar spine disease. [Orthopedics. 2017; 40(3):e520-e525.].

Glenohumeral arthritis as a risk factor for proximal humerus nonunion

BACKGROUND

Proximal humerus fractures are common injuries and nonsurgical treatment has proven to yield good to excellent clinical results. A small percentage of these fractures go on to delayed or nonunion and the incidence and risk factors for this complication are poorly understood. We hypothesize that adjacent joint stiffness of the glenohumeral joint might lead to an increased rate of nonunion for proximal humerus fractures.

METHODS

A search of the entire Medicare database from 2005 to 2011 was performed to identify 38,754 patients who sustained a proximal humerus fracture including 13,802 with co-existing ipsilateral shoulder osteoarthritis (OA) and 24,952 with co-existing diagnosis of rheumatoid arthritis (RA). A cohort of 301,987 patients served as a control. Medical co-morbidities and fracture complications were compared between the cohorts.

RESULTS

The incidence of delayed union at 3 and 6 months for OA and RA groups were significantly increased compared to control at 0.79% and 1.74%, and 0.67% and 1.86%, respectively (p < 0.001). Nonunion rates were also significantly increased (p < 0.001) in the OA and RA cohorts at 9 months and 1 year with incidences of 2.39%, 2.89% and 2.59% and 3.08%, Respectively. The incidence of nonunion in the control cohort at the same time points was 1.13% and 1.35%.

CONCLUSIONS

The coexistence of shoulder OA or a diagnosis of RA nearly doubled in the incidence of proximal humerus nonunion. This is the first study investigating this association in the shoulder and should be considered along with traditional nonunion risk factors in the treatment algorithm.

Total shoulder arthroplasty in patients with HIV infection: complications, comorbidities, and trends

BACKGROUND

Patients with human immunodeficiency virus (HIV) infection were previously at substantial risk for immunosuppression-related complications. As a result of highly active antiretroviral therapy, HIV-infected patients are living longer and are presenting for elective surgery. Outcomes in HIV-infected patients are well described for hip and knee arthroplasty but not for total shoulder arthroplasty (TSA). The purpose of this study was to examine postoperative complications of TSA in HIV-positive patients.

METHODS

We queried the entire 2005 to 2012 Medicare database. Current Procedural Terminology and International Classification of Diseases, Ninth Revision, Clinical Modification codes were used to identify the procedure, demographics, comorbidities, and postoperative complications. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

RESULTS

The query returned 2528 HIV-positive patients who underwent TSA or reverse TSA (RTSA). There was increased utilization of TSA and RTSA in this population from 2005 to 2012; 1353 patients had 2-year follow-up. These patients were slightly older and had higher prevalence of comorbidities, suggesting a sicker cohort. HIV-positive patients had alarmingly higher rates of 90-day cerebrovascular accident (OR, 35.98; CI, 30.34-42.67). HIV-positive patients had higher overall rates of broken prosthetic joints (OR, 1.72; CI, 1.20-2.47), periprosthetic infection (OR, 1.36; CI, 1.01-1.82), and TSA revision or repair (OR, 2.44; CI, 1.81-3.28).

CONCLUSIONS

To our knowledge, this is the first study that directly examines the postoperative outcomes of HIV-positive patients after TSA or RTSA. As more of these patients present for surgery, surgeons should be aware that these patients might be at increased risk for certain postoperative surgical and medical complications.

Psychiatric disorders increase complication rate after primary total knee arthroplasty

BACKGROUND

Psychiatric disease is difficult to screen preoperatively and the incidence of mental health disorders in patients undergoing total knee arthroplasty (TKA) may be underappreciated. The purpose of this study is to evaluate the perioperative complication profile in patients with psychiatric disorders.

METHODS

A search of the entire Medicare database from 2005 to 2011 was performed to identify patients who underwent primary TKA with bipolar disorder (20,972), depression (187,448), and schizophrenia (7607). A cohort of 1,271,464 patients as controls with minimum 2.5-year follow-up. Medial and surgical complications at 30-days, 90-days, and overall were compared between the two cohorts.

RESULTS

Patients with any psychiatric disease were more likely to be younger (age<65 OR 5.5, p<0.001), female (OR 2.61, p<0.001), and more medically complex (significant increase in 28/28 Elixhauser medical comorbidities, p<0.05). There was a significant increase (p<0.001) in 11/14 (78.5%) of recorded postoperative medical complication rates at 90-days. There was a statistically significant increase in periprosthetic infection (OR 2.17 p<0.001), periprosthetic fracture (OR 2.40, p<0.001), revision TKA (OR 2.06, p<0.001), and extensor mechanism rupture (OR 2.41, p<0.001) at 90day and overall time points.

CONCLUSIONS

Patients with psychiatric disorders who undergo elective primary TKA have significantly increased medical and surgical complication rates in the global period and short term follow-up. An ideal screening tool is yet to be determined and these patients need to be counseled appropriately regarding the increased complication rates before proceeding with TKA.

Complications Are Not Increased With Acetabular Revision of Metal-on-metal Total Hip Arthroplasty

BACKGROUND

Isolated revision of the acetabular component in the setting of total hip arthroplasty has an increased risk of dislocation. With local soft tissue destruction frequently associated with failed metal-on-metal (MoM) bearings, it is presumed that acetabular revision of these hips will have even greater risk of complications. However, no study directly compares the complications of MoM with metal-on-polyethylene (MoP) acetabular revisions.

QUESTIONS/PURPOSES

In the context of a large database analysis, we asked the following questions: (1) Are there differences in early medical or wound complications after isolated acetabular revision of MoM and MoP bearing surfaces? (2) Are there differences in the frequency of dislocation, deep infection, and rerevision based on the bearing surface of the original implant?

METHODS

A review of the 100% Medicare database from 2005 to 2012 was performed using International Classification of Diseases, 9th Revision and Current Procedural Terminology codes. We identified 451 patients with a MoM bearing and 628 patients with a MoP bearing who had an isolated acetabular revision and a minimum followup of 2 years. The incidence, odds ratios, and 95% confidence intervals for early medical or wound complications were calculated using a univariate analysis at 30 days with patient sex and age group-adjusted analysis for blood transfusion. The incidence, odds ratio, and 95% confidence intervals for dislocation, deep infection, and rerevision were calculated using a univariate analysis at 30 day, 90 days, 1 year, and 2 years using a subgroup analysis with the Cochran-Mantel-Haenszel test to adjust for patient gender and age groups.

RESULTS

There were no differences between the MoM and MoP isolated acetabular revisions in the incidence of 30-day local complications. There was a greater risk of transfusion in the MoP group than the MoM group (134 of 451 [30%] versus 230 of 628 [37%]; odds ratio [OR], 0.731; 95% confidence interval [CI], 0.565-0.948; p = 0.018). There were no differences at 2 years between the MoM and MoP acetabular revisions in the incidence of dislocation, infection, or rerevision. When analyzed by patient sex and age group, there were more infections in the age 70 to 79 years MoP group compared with MoM (10 of 451 [5%] versus 29 of 628 [10%]; OR, 4.47; CI, 1.699-11.761; p = 0.001).

CONCLUSIONS

There were high rates of dislocation, infection, and rerevision in both revision cohorts. The rate of dislocation was not greater after acetabular revision of MoM bearings at 2 years. Based on these findings, clinicians should counsel these patients preoperatively about the risks of these complications. Dual-mobility and constrained components have specific advantages and disadvantages in these settings and should be further studied.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Lingering Risk: Bariatric Surgery Before Total Knee Arthroplasty

BACKGROUND

Obesity continues to increase in the United States with an estimated 35% obesity and 8% bariatric (body mass index >40) rate in adults. Bariatric patients seek advice from arthroplasty surgeons regarding the temporality of bariatric surgery (BS), yet no consensus currently exists in the literature.

METHODS

A total of 39,014 patients were identified in a claim-based review of the entire Medicare database with International Classification of Diseases, Ninth Revision codes to identify patients in 3 groups. Patients who underwent BS before total knee arthroplasty (group I: 5914 experimental group) and 2 control groups that did not undergo BS but had either a body mass index >40 (group II: 6480 bariatric control) or <25 (group III: 26,616 normal weight control). International Classification of Diseases, Ninth Revision, Clinical Modification codes identified preoperative demographics or comorbidities and evaluated short-term medical (30 day) and long-term surgical (90 days and 2 years) complications.

RESULTS

Group I had the greatest female predominance, youngest age, and highest incidence of: deficiency anemia, cardiovascular disease, pulmonary disease, liver disease, ulcer disease, polysubstance abuse, psychiatric disorders, and smoking. Medical and surgical complication incidences were greatest in group I including: 4.98% deep vein thrombosis; 5.31% pneumonia; 10.09% heart failure; and 2-year infection, revision, and manipulation rates of 5.8%, 7.38%, and 3.13%, respectively. These values were significant elevation compared to III and slightly greater than II.

CONCLUSIONS

This study demonstrates that BS before total knee arthroplasty is associated with greater risk compared to both nonobese and obese patients. This is possibly due to a higher incidence of medical or psychiatric comorbidities determined in the Medicare BS patients, wound healing difficulties secondary to gastrointestinal malabsorption, malnourishment from prolonged catabolic state, rapid weight loss before surgery, and/or age.

Cervical Myelopathy Doubles the Rate of Dislocation and Fracture After Total Hip Arthroplasty

BACKGROUND

Cervical spondylotic myelopathy (CSM) is a common and underdiagnosed cause of gait dysfunction, rigidity, and falls in the elderly. Given the frequent concurrency of CSM and hip osteoarthritis, this study is designed to evaluate the relative risk of CSM on perioperative and short-term outcomes after total hip arthroplasty (THA).

METHODS

The Medicare Standard Analytical Files were searched from 2005 to 2012 to identify all patients undergoing primary THA and the subset of patients with preexisting CSM. Risk ratios with 95% confidence intervals were calculated for 90-day, 1-year, and overall follow-up for common postoperative complications: periprosthetic dislocation, fracture, infection, revision THA, and wound complications.

RESULTS

The risk ratios of all surgical complications, including dislocation, periprosthetic fractures, and prosthetic joint infection, were increased approximately 2-fold at all postoperative time points for patients.

CONCLUSION

Preexisting CSM is a significant risk factor for primary THA complications including dislocation, periprosthetic fractures, and prosthetic joint infection.

How Do Previous Solid Organ Transplant Recipients Fare After Primary Total Knee Arthroplasty?

INTRODUCTION

Total knee arthroplasty (TKA) has been proven to increase knee outcome scores after solid organ transplantation (SOT), but many authors are concerned about a higher complication rate. The purpose of this study is to evaluate the complication profile of TKA after previous SOT.

METHODS

A search of the entire Medicare database from 2005 to 2011 was performed using International Classification of Disease, version 9, codes to identify 3339 patients who underwent TKA after 1 or more solid organ transplants including the kidney (2321), liver (772), lung (129), heart (412), and pancreas (167). A cohort of 1,685,295 patients served as a control with minimum 2-year follow-up. Postoperative complications at 30-day, 90-day, and overall time points were compared between the 2 cohorts.

RESULTS

Patients with any SOT were younger (age: <65, odds ratio [OR]: 6.58, P < .001), male (OR: 1.88, P < .001), and medically complex (significant increase in 28 of 29 Elixhauser comorbidities, P < .05). There was a significant increase (P < .05) in 11 of 13 (84.6%) recorded postoperative medical complications rates at 90 days. There was a significant increase overall in periprosthetic infection (OR: 2.11, P < .001), periprosthetic fracture (OR: 1.78, P < .001), and TKA revision (OR: 1.36, P < .001). When analyzed by individual organ, heart and lung transplants carried the fewest medical and surgical complications.

CONCLUSION

The results of this study demonstrate that patients with previous SOT who undergo elective primary TKA have more postoperative complications in the global period and at short-term follow-up. Yet, complication profiles by individual organ varied significantly.

Outcomes after Total Knee Arthroplasty for post-traumatic arthritis

INTRODUCTION

Total Knee Arthroplasty (TKA) is an important treatment for posttraumatic arthritis (PTA), but evidence on outcomes is sparse. The purpose of this study was to evaluate the impact of PTA versus primary osteoarthritis (OA) on postoperative outcomes after TKA.

METHODS

We queried the entire Medicare database from 2005 to 2012. International Classification of Diseases, 9th revision and Current Procedural Terminology codes were used to identify the procedure, indication, and complications. Patients with minimum two-years follow-up were selected. Odds ratios (ORs), confidence intervals, and p-values (p) were calculated.

RESULTS

For PTA, 3509 patients had TKA. For OA, 257,611 patients with TKA served as controls. The average Charlson Comorbidity Index for both groups was five. PTA patients were younger; only eight out of 29 Elixhauser comorbidities were higher. PTA patients had higher incidence of periprosthetic infection (OR 1.72, p<0.001), cellulitis or seroma (OR 1.19, p<0.001), knee wound complications (OR 1.80, p<0.001), TKA revision (OR 1.23, p=0.01), and arthrotomy/incision and drainage (OR 1.55, p<0.001). Blood transfusion rate was lower in PTA patients. There were no significant differences in bleeding complications, prosthetic dislocation, broken prostheses, periprosthetic fracture, osteolysis and polywear, neurovascular injury, and extensor mechanism rupture.

DISCUSSION AND CONCLUSION

This study represents, to our knowledge, TKA outcomes in the largest cohort of PTA patients to date. Our findings indicate that these patients are at higher risk for many, but not all, postoperative surgical complications despite being as healthy as patients receiving TKA for primary OA.