Increased In-Hospital Lengths of Stay, Readmission Rates, Complications, and Costs in Patients Who Have Depressive Disorders Following Primary Total Hip Arthroplasty.

INTRODUCTION: Recent studies have shown the prevalence of depressive disorders has increased within the United States. Studies investigating the impact of depressive disorders following primary THA are limited. Therefore, the purpose of this study was to determine whether patients with depressive disorders have higher rates of: 1) in-hospital lengths of stay (LOS); 2) readmission rates; 3) medical complications; and 4) implant-related complications. MATERIALS AND METHODS: A retrospective query of the Humana claims database was performed. Patients undergoing primary THA with a history of depressive disorders were identified by International Classification of Disease, Ninth Revision (ICD-9), and Current Procedural Terminology (CPT) codes. Study group patients were matched to controls in a 1:5 ratio by age, sex, and comorbidities. The query yielded 67,245 patients with (n=11,255) and without (n=55,990) depressive disorders. Welch's t-tests were used to test for significance in LOS between the cohorts; whereas, logistics regression analyses were used for complications and readmissions. A p-value less than 0.003 was statistically significant. RESULTS: Patients with depressive disorders undergoing primary THA had significantly longer in-hospital LOS (6.59 days vs. 2.96 days, p <0.0001). Additionally, patients with depressive disorders had higher incidence and odds of readmission rates (46.02 vs. 35.43%; OR: 1.55, p <0.0001), medical complications (7.05 vs. 1.84%; OR: 4.04, p <0.0001), and implant-related complications (5.76 vs. 2.75%; OR: 2.16, p <0.0001) compared to patients without depressive disorders. CONCLUSION: After matching age, sex, and medical comorbidities, the results of the study demonstrate patients with depressive disorders have longer in-hospital LOS and increased rates of complications and readmission rates. The study is useful as it can allow orthopedic surgeons to properly counsel these patients of the potential complications which may arise following their procedure.

Impact of Biological Sex on Complications, Lengths of Stay, Readmission Rates, and Costs of Care Following Primary Total Knee Arthroplasty.

The impact of gender on total knee arthroplasty (TKA) postoperative complications, readmission rates, and costs of care has not been often evaluated. Therefore, the purpose of this study was to investigate which sex had higher rates of: (1) medical complications; (2) implant complications; (3) lengths of stay (LOSs); (4) readmission rates; and (5) costs after TKA. A query was performed using an administrative claims database from January 1, 2005, to March 31, 2015. Patients who had TKAs were identified using International Classification of Diseases, Ninth Revision and Current Procedural Terminology codes. Males and females were filtered separately and matched according to age and various medical comorbidities leading to 1,590,626 patients equally distributed. Primary outcomes analyzed included 90-day medical complications, LOSs, 90-day readmission rates, in addition to day of surgery and total global 90-day episode of care costs. Pearson's chi-square analyses were used to compare medical complications and readmission rates. Welch's t-tests were used to test for significance in matching outcomes and costs. A p-value of less than 0.01 was considered statistically significant. Males had a smaller risk of complications than women (1.35 vs. 1.40%, p < 0.006) and higher rates of implant-related complications (2.28 vs. 1.99%, p < 0.0001). Mean LOSs were lower for males: 3.16 versus 3.34 days (p < 0.0001). The 90-day readmission rates were higher in men (9.67 vs. 8.12%, p < 0.0001). This study demonstrated that males undergoing primary TKA have lower medical complications and shorter LOSs then their female counterparts. However, males have higher implant-related complications, readmission rates, and costs of care.

Adoption of Robotic-Arm-Assisted Total Knee Arthroplasty Is Associated with Decreased Use of Articular Constraint and Manipulation under Anesthesia Compared to a Manual Approach.

Haptic robotic-arm-assisted total knee arthroplasty (RATKA) seeks to leverage three-dimensional planning, intraoperative assessment of ligament laxity, and guided bone preparation to establish and achieve patient-specific targets for implant position. We sought to compare (1) operative details, (2) knee alignment, (3) recovery of knee function, and (4) complications during adoption of this technique to our experience with manual TKA. We compared 120 RATKAs performed between December 2016 and July 2018 to 120 consecutive manual TKAs performed between May 2015 and January 2017. Operative details, lengths of stay (LOS), and discharge dispositions were collected. Tibiofemoral angles, Knee Society Scores (KSS), and ranges of motion were assessed until 3 months postoperatively. Manipulations under anesthesia, complications, and reoperations were tabulated. Mean operative times were 22 minutes longer in RATKA (p < 0.001) for this early cohort, but decreased by 27 minutes (p < 0.001) from the first 25 RATKA cases to the last 25 RATKA cases. Less articular constraint was used to achieve stability in RATKA (93 vs. 55% cruciate-retaining, p < 0.001; 3 vs. 35% posterior stabilized (PS), p < 0.001; and 4 vs. 10% varus-valgus constrained, p_ = _0.127). RATKA had lower LOS (2.7 vs. 3.4 days, p < 0.001). Discharge dispositions, tibiofemoral angles, KSS, and knee flexion angles did not differ, but manipulations were less common in RATKAs (4 vs. 17%, p = 0.013). We observed less use of constraint, shorter LOS, and fewer manipulations under anesthesia in RATKA, with no increase in complications. Operative times were longer, particularly early in the learning curve, but improved with experience. All measured patient-centered outcomes were equivalent or favored the newer technique, suggesting that RATKA with patient-specific alignment targets does not compromise initial quality. Observed differences may relate to improved ligament balance or diminished need for ligament release.

Impact of depressive disorders on primary total shoulder arthroplasties: a matched control analysis of 113,648 Medicare patients.

INTRODUCTION: The purpose of this study was to investigate whether patients with depressive disorders undergoing primary total shoulder arthroplasty have higher rates of (1) in-hospital lengths of stay, (2) readmission rates, (3) medical complications, and (4) implant-related complications. METHODS: A retrospective query was performed using a national claims database. Study group patients were matched to controls in a 1:5 ratio according to age, sex, and medical comorbidities. The query yielded 113,648 patients who were with (n = 18,953) and without (n = 94,695) depressive disorders. Pearson's χ2 analyses were used to compare patient demographics. Logistic regression analyses were used to calculate odds-ratios of complications and readmission rates. Welch's t-tests were used to test for significance for in-hospital lengths of stay. A p-value less than 0.003 was considered statistically significant. RESULTS: Study group patients had significantly longer in-hospital lengths of stay (2.7 days versus 2.3 days; p < 0.0001). Patients who have depressive disorders had higher incidences and odds of readmissions (9.4 versus 6.15%; odds-ratio: 1.6, p < 0.0001), medical complications (2.7 versus 0.9%; odds-ratio: 3.0, p < 0.0001), and implant-related complications (6.1 versus 2.4%; odds-ratio: 2.59, p < 0.0001) compared to controls. CONCLUSION: Depressive disorder patients have longer in-hospital lengths of stay and increased odds of readmissions and complications following primary total shoulder arthroplasty.

Reasons and Risk Factors for Emergency Department Visits After Primary Total Knee Arthroplasty: An Analysis of 1.3 Million Patients.

BACKGROUND: Well-powered studies investigating the relationship of emergency department (ED) visits and total knee arthroplasty (TKA) are limited. Therefore, the specific aims of this study were to: 1) compare patient demographics of patients who did and did not have an ED visit; and for the visits, identified: 2) leading reasons; and 3) risk factors for ED visits (prearthroplasty/postarthroplasty). METHODS: Patients undergoing primary TKA who had an ED visit within 90 days after their index procedure were identified from a nationwide database. The query yielded 1,364,655 patients who did (n = 5689) and did not have (n = 1,358,966) an ED visit. Baseline demographics such as age, sex, and comorbidity prevalence between the two cohorts; reasons for ED visits; and prearthroplasty and postarthroplasty risk factors were analyzed. Odds ratios (ORs) of ED visits were assessed using multivariate binomial logistic regression analyses. A P-value less than 0.001 was considered statistically significant. RESULTS: Patients who did and did not have ED visits differed with respect to age (P < .0001) and mean Elixhauser Comorbidity Index scores (9 vs 6, P < .0001). Musculoskeletal etiologies were the most common reason for ED visits. Hypertension was the greatest contributor to ED visits prearthroplasty and postarthroplasty. Comorbid conditions associated with ED visits postarthroplasty included peripheral vascular disease (OR: 1.61, P < .0001), coagulopathy (OR: 1.58, P < .0001), and rheumatoid arthritis (OR: 1.56, P < .0001). CONCLUSION: By identifying demographic patterns of patients, reasons, and risk factors, the information found from this study can help identify targets for quality improvement to potentially reduce the incidence of ED visits after primary TKA.

Annual Nationwide Infection Trends for Revision Total Knee Arthroplasty.

Several recent intraoperative and wound management techniques have been developed and implemented in the United States over the past decade; however, it is unclear what the effects of these newer modalities have on reducing surgical site infection (SSI) rates. Therefore, the purpose of this study was to track the annual rate and trends of (1) overall, (2) deep, and (3) superficial SSIs following revision total knee arthroplasty (TKA). The National Surgical Quality Improvement Program database was queried for all revision TKA cases performed between 2011 and 2016, which yielded 9,887 cases. Cases with superficial and/or deep SSIs were analyzed separately and then combined to evaluate overall SSI rates. After an overall 6-year correlation and trends analysis, univariate analysis was performed to compare the most recent year, 2016, with the preceding 5 years. Correlation coefficients and chi-square tests were used to determine correlation and statistical significance. No significant correlations between combined, deep, and/or superficial SSI rates and year were noted (p > 0.05). The lowest overall SSI incidence was in 2012 (1.16%), while the greatest incidence was in 2014 (1.76%). The deep SSI incidence over the 6 years was 0.67% (66 out of 9,887 cases). Deep SSI rate decreased by 10% in 2016 compared with 2011 (0.50 vs. 0.56%, p > 0.05). In this 6-year period, 94 cases out of 9,887 were complicated by a superficial SSI, an incidence of 0.95%. The lowest superficial SSI incidence occurred in 2015 (n = 17, 0.77%). Overall, the incidence of SSIs in revision TKA has remained fairly low with some annual variance, indicating room for improvement. These variations likely as revision surgeries can be more complex and have several associated confounding factors influencing outcomes, when compared with primary cases. Further research is needed to identify revision-specific strategies to reduce the risk of surgical site infections.

Management of osteonecrosis of the femoral head.

AIMS: Earlier studies dealing with trends in the management of osteonecrosis of the femoral head (ONFH) identified an increasing rate of total hip arthroplasties (THAs) and a decreasing rate of joint-preserving procedures between 1992 and 2008. In an effort to assess new trends in the management of this condition, this study evaluated the annual trends of joint-preserving versus arthroplasties for patients aged < or > 50 years old, and the incidence of specific operative management techniques. METHODS: A total of 219,371 patients with ONFH were identified from a nationwide database between 1 January 2009 and 31 December 2015. The mean age was 54 years (18 to 90) and 105,298 (48%) were female. The diagnosis was made using International Classification of Disease, Ninth revision, Clinical Modification (ICD-9-CM) and Tenth Revision, Clinical Modification (ICD-10-CM) procedure codes. The percentage of patients managed using each procedure during each year was calculated and compared between years. The trends in the use of the types of procedure were also evaluated. RESULTS: The rate of joint-preserving procedures was significantly higher in patients aged < 50 years compared with those aged > 50 years (4.93% vs 1.52%; p < 0.001). For the overall cohort, rates of arthroplasty were far greater than those for joint-preserving procedures. THA was the most commonly performed procedure (291,114; 94.03%), while osteotomy (3,598; 1.16%), partial arthroplasty (9,171; 2.96%), core decompression (1,200; 0.39%), and bone graft (3,026; 0.98%) were performed markedly less frequently. The annual percentage of patients managed using a THA (93.56% to 89.52%; p < 0.001), resurfacing (1.22% to 0.19%; p < 0.001), and osteotomy (1.31% to 1.05%; p < 0.001) also decreased during the study period. CONCLUSION: We found that patients with ONFH have been most commonly managed with non-joint-preserving procedures. Our findings provide valuable insight into the current management of this condition and should increase efforts being made to save the hip joint. Cite this article: Bone Joint J 2020;102-B(7 Supple B):122-128.

Opioid Use Disorder Is Associated with an Increased Risk of Infection after Total Joint Arthroplasty: A Large Database Study.

BACKGROUND: Recent studies have shown that patients with opioid use disorder have impaired immunity. However, few studies with large patient populations have evaluated the risks of surgical site infection (SSI) and prosthetic joint infection (PJI) with opioid use disorder after total joint arthroplasty (TJA), and there is a lack of evidence for revision TJA in particular. QUESTIONS/PURPOSES: Are patients with opioid use disorder who undergo (1) primary THA, (2) primary TKA, (3) revision THA, or (4) revision TKA at a higher risk of experiencing SSIs 90 days after surgery or PJIs 2 years after surgery than those who do not have opioid use disorder? METHODS: All primary and revision TJAs performed between 2005 and 2014 were identified from the Medicare Analytical Files of the PearlDiver Supercomputer using ICD-9 codes. This database is one of the largest nationwide databases; it comprehensively and longitudinally tracks patients based on all insurance claims rather than particular hospital visits, and has a low error rate (estimated at 1.3%). Boolean command operators were used to form a study group of patients with a history of opioid use disorder before surgery. ICD-9 diagnosis codes 304.00 to 304.02 and 305.50 to 305.52 were used to identify patients with opioid use disorder. Study group patients were matched 1:1 to control participants without opioid use disorder undergoing TJA, according to age, sex, and comorbidity burden (Elixhauser comorbidity index [ECI]). The ECI is comprised of 31 different comorbidities and can be used for large administrative databases. The query yielded a study population of 54,332 patients: 14,944 undergoing primary THA (opioid use disorder: n = 7472), 23,680 undergoing primary TKA (opioid use disorder: n = 11,840), 8116 undergoing revision THA (opioid use disorder: n = 4058), and 7592 undergoing revision TKA (opioid use disorder: n = 3796). The primary outcomes analyzed were SSI at 90 days and PJI at 2 years postoperatively, which were identified with ICD-9 codes. Logistic regression analyses were performed to calculate the risk that an infection would develop in a patient with opioid use disorder compared with the matched control patients without opioid use disorder. RESULTS: Patients with opioid use disorder undergoing primary THA had an increased risk of SSI at 90 days (OR 1.85 [95% CI 1.51 to 2.25]; p < 0.001) and PJI at 2 years (OR 1.66 [95% CI 1.42 to 1.93]; p < 0.001). Compared with matched controls, opioid use disorder patients undergoing primary TKA had an increased risk of SSI at 90 days (OR 1.72 [95% CI 1.46 to 2.02]; p < 0.001) and PJI at 2 years (OR 1.31 [95% CI 1.16 to 1.47]; p < 0.001). Similarly, for revision THAs, there was an increase in 90-day SSIs (OR 1.89 [95% CI 1.53 to 2.32]; p < 0.001) and 2-year PJIs (OR 4.24 [95% CI 3.67 to 4.89]; p < 0.001). The same held for revision TKAs for 90-day SSIs (OR 1.88 [95% CI 1.53 to 2.29]; p < 0.001) and 2-year PJIs (OR 4.94 [95% CI 4.24 to 5.76]; p < 0.001). CONCLUSIONS: After accounting for age, sex, and comorbidity burden, these results revealed that patients with opioid use disorder undergoing TJA were at increased risk of having SSIs and PJIs. Based on these findings, healthcare systems and/or administrators should recognize the increased associated PJI and SSI risks in patients with opioid use disorder and enact clinical policies that reflect these associated risks. Additionally, these findings should encourage surgeons to pursue multidisciplinary approaches to help patients reduce their opioid consumption before their arthroplasty procedure. LEVEL OF EVIDENCE: Level III, therapeutic study.

What Are Risk Factors for Infection after Primary or Revision Total Joint Arthroplasty in Patients Older Than 80 Years?

BACKGROUND: Patients older than 80 years of age form an increasing proportion of the patient population undergoing total joint arthroplasty (TJA). With increasing life expectancy and the success of TJA, orthopaedic surgeons are more likely to operate on patients older than 80 years than ever before. Given that most other studies focus on younger populations, only evaluate primary TJA, or limit patient populations to institutional or regional data, we felt a large-database, nationwide analysis of this demographic cohort was warranted, and we wished to consider both primary and revision TJA. QUESTIONS/PURPOSES: In this study, we sought to investigate the risk factors for surgical site infections (SSIs) at 90 days and periprosthetic joint infections (PJIs) at 2 years after surgery in patients aged 80 years and older undergoing (1) primary and (2) revision lower extremity TJA. METHODS: All patients aged 80 years or older who underwent primary or revision TJA between 2005 and 2014 were identified using the Medicare Analytical Files of the PearlDiver Supercomputer using ICD-9 codes. This database is unique in that it is one of the largest nationwide databases, and so it provides a large enough sample size of patients 80 years or older. Additionally, this database provides comprehensive and longitudinal patient data tracking, and a low error rate. Our final cohort consisted of 503,241 patients (TKA: n = 275,717; THA: n = 162,489; revision TKA: n = 28,779; revision THA: n = 36,256). Multivariate logistic regression models were constructed to evaluate the association of risk factors on the incidences of 90-day SSI and 2-year PJI. Variables such as sex, diabetes, BMI, and congestive heart failure, were included in the multivariate regression models. Several high-risk comorbidities as identified by the Charlson and Elixhauser comorbidity indices were selected to construct the models. We performed a Bonferroni-adjusted correction to account for the fact that multiple statistical comparisons were made, with a p value < 0.002 being considered statistically significant. RESULTS: For primary TKA patients, an increased risk of 90-day SSIs was associated with male sex (OR 1.28 [95% CI 1.25 to 1.52]; p < 0.001), BMI greater than 25 k/m (p < 0.001), and other comorbidities. For primary THA patients, an increased risk of 90-day SSIs was associated with patients with obesity (BMI 30-39 kg/m; OR 1.91 [95% CI 1.60 to 2.26]; p < 0.001) and those with morbid obesity (BMI 40-70 kg/m; OR 2.58 [95% CI 1.95 to 3.36]; p < 0.001). For revision TKA patients, an increased risk of SSI was associated with iron-deficiency anemia (OR 1.82 [95% CI 1.37 to 2.28]; p < 0.001). For revision THA patients, electrolyte imbalance (OR 1.48 [95% CI 1.23 to 1.79]; p < 0.001) and iron-deficiency anemia (OR 1.63 [95% CI 1.35 to 1.99]; p < 0.001) were associated with an increased risk of 90-day SSI. Similar associations were noted for PJI in each cohort. CONCLUSIONS: These findings show that in this population, male sex, obesity, hypertension, iron-deficiency anemia, among other high-risk comorbidities are associated with a higher risk of SSIs and PJIs. Based on these findings, orthopaedic surgeons should actively engage in comanagement strategies with internists and other specialists to address modifiable risk factors through practices such as weight management programs, blood pressure reduction, and electrolyte balancing. Furthermore, this data should encourage healthcare systems and policy makers to recognize that this patient demographic is at increased risks for PJI or SSI, and these risks must be considered when negotiating payment bundles. LEVEL OF EVIDENCE: Level III, therapeutic study.

Outcomes of Cementless-Backed Patellar Components.

Because of the early follow-up positive outcomes with cementless fixation, continued evaluations need to be performed to ensure longer-term efficacy. Additionally, although many studies report on the results of femoral and tibial component fixation, few studies report specifically on patellar outcomes. Therefore, the purpose of this study was to report on the: (1) implant survivorship; (2) complications; and (3) radiographic outcomes in a large cohort of patients who received cementless total knee arthroplasties (TKAs), with particular attention to the patellar component. A total of 261 patients who underwent cementless TKA by a single, high-volume academic surgeon were studied. Patients had a mean age of 66 years and were distributed between 192 women (74%) and 69 men. All patients received the same cementless tibial, femoral, and patellar components. Mean follow-up period was 4.5 years (range, 4-5 years). Primary outcomes evaluated included all postoperative complications, with particular emphasis on the patellar component. Only one patellar loosened leading to a patellar aseptic loosening rate of 0.3% (1 of 261). The one patellar loosening was the component being dislodged after a manipulation under anesthesia (MUA) at 6 weeks. This was revised to a cemented component and the patient is doing well 4 years later. A second patient experienced a patellar tendon rupture, later surgically repaired. Another patient sustained a patella fracture that was managed nonoperatively. The fracture healed by 1 year and the patient continued to have an otherwise successful outcome, now at 2 years follow-up. No progressive radiolucencies, subsidence, or changes in initial postoperative axial alignment were observed at final follow-up. The results from this study highlight a 98% success rate at mean 4.5 years follow-up in a large cohort of patients with a diverse spread of demographic details. Specific to the patella, only one patient experienced an adverse event, which was managed nonoperatively. Therefore, based on this data, patellar fixation in cementless TKA can be considered a safe technique.

Cementless Tritanium Baseplate Total Knee Arthroplasty: Survivorship and Outcomes at 5-Year Minimum Follow-Up.

BACKGROUND: Newer generation cementless total knee arthroplasty (TKA) designs have provided stronger osteointegration between the implant and bone. Despite excellent survivorship and outcomes with cemented TKAs, areas of concern within the bone-cement interface remain a concern and necessitate studies on alternative constructs. This study assesses: (1) implant survivorship; (2) clinical outcomes; and (3) complications with radiographic outcomes at a 5-year minimum follow-up of cementless highly porous titanium-coated baseplates in TKAs. METHODS: Part of this study has been reported. We retrospectively reviewed a prospectively collected database at a single high-volume institution between July 1, 2013 and June 30, 2014 for patients who underwent a primary TKA using cementless highly porous titanium-coated baseplate implants. Patients were evaluated clinically at postoperative follow-up visits at a minimum of 5 years. To calculate the survivorship, Kaplan-Meier analysis was performed to determine all-cause, aseptic, and septic implant survivorship at each final follow-up for all patients. RESULTS: A total of 228 TKAs were performed and followed for a minimum of 5 years (range, 5-6 years). As of the latest follow-up, one case of septic loosening of the patellar button and one case of patellar dislodgment secondary to physical manipulation were recorded and revised. Overall, the cohort displayed implant survivorship of 99.5% at 5-year minimum follow-up. Improvements were seen in both Knee Society pain and function scores and were 37 points (range, 17-60 points) and 28 points (range, 15-47 points), respectively. The mean improvement in flexion was 17.8 (range, -20 to 40 degrees) and mean improvement in extension was -5.5 (range, -30 to 5 degrees). DISCUSSION: Cementless TKAs serve as strong alternative choice to cemented TKAs. Although cemented fixation is commonly known as the gold standard, results of this study confirm the findings of previous investigations on the survivorship of cementless TKA implants. Therefore, patients who undergo primary TKA with a cementless tritanium baseplate can expect excellent clinical outcomes at a 5-year minimum follow-up.

Robotic-Assisted Versus Manual Unicompartmental Knee Arthroplasty: A Systematic Review.

INTRODUCTION: Unicompartmental knee arthroplasty (UKA) is a feasible alternative to total knee arthroplasty (TKA) for selected patients with severe single-compartment knee osteoarthritis. Robotic-assisted UKA (rUKA) has recently emerged as a complementary tool to ameliorate previous difficulties with manual UKA (mUKA). However, the influence of rUKA compared to mUKA on patient outcomes are still largely unknown. PURPOSE: To compare outcomes of the manual technique and a single robotic-assisted system in patients undergoing unicompartmental knee arthroplasty. MATERIALS AND METHODS: The PubMed-Medline was searched using terms: "robotic," "unicompartmental," "knee," and "arthroplasty" to identify all studies comparing outcomes of mUKA and rUKA. Data pertaining to the following outcomes were extracted: (1) studies comparing robotic-assisted UKA to manual UKA; (2) reports which only included the Mako UKA system (Mako Surgical Corporation, Fort Lauderdale, Florida) as the robotic-assisted system; and (3) studies which discussed implant survivorship, complications, early postoperative parameters, functional outcomes, or implant positioning. Review articles were excluded. RESULTS: A total of eight publications with 337 patients who underwent rUKA and 481 who underwent mUKA were included in our analysis. Two studies reported that early postoperative pain was decreased with rUKA compared to mUKA. In one study, pain levels in the first eight postoperative weeks were 54% lower in the rUKA group and in the other, pain scores based on the numeric rating scale were significantly lower in rUKA (2.5) compared to mUKA (4.2) upon discharge (p<0.001). Furthermore, mean time to hospital discharge in this study was reduced with rUKA (42.5 ± 5.9 hours) compared to mUKA (71.1 ± 14.6 hours) (p<0.001). One study demonstrated a significant improvement in range of motion at two-year follow up in the rUKA group (15°, range, 5° to 25°) compared to the mUKA group (10°, range 0° to 20°; p=0.04). One study reported that at three-month follow up, mean Knee Society scores were significantly better in the rUKA group (164; interquartile range [IQR] 131 to 178) compared the mUKA group (143; IQR 132 to 166; p=0.04). Three studies reported more accurate implant positioning with rUKA compared to mUKA. Among the five studies that reported implant survivorship, four studies (including a randomized control trial) found no difference between techniques in implant survival rate, while one retrospective analysis reported improved survivorship with mUKA. CONCLUSIONS: In conclusion, unicompartmental knee arthroplasty implants demonstrated comparable survivorship rates whether performed manually or with robotic assistance. However, compared to the manually performed procedure, robotic-assisted unicompartmental knee arthroplasty were found to offer benefits including shorter lengths of hospital stays, decreased postoperative pain scores, and improved functional outcomes.

Chronic Obstructive Pulmonary Disease Is Associated With Higher Rates of Venous Thromboemboli Following Primary Total Knee Arthroplasty.

BACKGROUND: There is discordance in the literature regarding the presence of chronic obstructive pulmonary disease (COPD) and the development of venous thromboemboli (VTEs). Therefore, the purpose of this study is to determine whether COPD patients undergoing primary total knee arthroplasty (TKA) have higher rates of (1) in-hospital lengths of stay (LOS); (2) readmissions; (3) VTEs; and (4) costs of care. METHODS: COPD patients undergoing primary TKA were identified and matched to controls in a 1:5 ratio by age, gender, and medical comorbidities. Patients with a history of VTEs or hypercoagulable states were excluded. The query yielded 211,378 patients in the study (n = 35,230) and control (n = 176,148) cohorts. Outcomes analyzed included in-hospital LOS, readmission rates, VTEs, and costs of care. A P-value less than .01 was considered statistically significant. RESULTS: COPD patients were found to have significantly longer in-hospital LOS (4 vs 3 days, P < .0001). Study group patients were also found to have significantly higher incidence and odds ratio (OR) of readmission rates (20.9% vs 16.3%; OR 1.36, P < .0001) and VTEs (1.75 vs .93; OR 1.18, P < .0001). Additionally, the study demonstrated that COPD patients incurred higher 90-day episode-of-care costs ($15,626.85 vs $14,471.29, P < .0001). CONCLUSION: After adjusting for confounding variables, our study found an association between COPD and higher rates of developing VTEs following primary TKA. The study can be used by orthopedic surgeons to adequately counsel and educate these patients of the potential complications which may arise following their TKA.

Computer-Assisted Navigation in Total Knee Arthroplasty.

Manual total knee arthroplasty (TKA) has successfully treated end-stage knee osteoarthritis for several years. However, recent technological advancements have enabled surgeons to perform TKA with more accuracy and precision. Aligning the femoral and tibial components perpendicular to the mechanical axes of the femur and tibia is a fundamental principle for restoring knee kinematics and soft-tissue balance. Computer-assisted robotic TKA has proven its ability to fine tune lower leg alignment, component position, and soft-tissue balancing. Furthermore, robotic-assisted TKA (RATKA) offers the additional benefit of improving soft-tissue protection compared to manual techniques. Numerous systems have been developed in the advancement of technology in computer processing, and the number of robotic surgical systems is increasing as well. The three main categories of navigation systems can be classified as: image-based console navigation, imageless console navigation, and accelerometer-based handheld navigation systems. The purpose of this review was to describe emerging technologies for TKA. Specifically, we outline the available literature pertaining to each system with regards to their: (1) accuracy and precision of component alignment; (2) soft-tissue protection; (3) postoperative outcomes; and (4) other reported outcomes such as costs.

Does Hypothyroidism Increase Complications, Lengths of Stay, Readmissions, and Costs Following Primary 1- to 2-Level Lumbar Fusion?

STUDY DESIGN: Level III-retrospective review. OBJECTIVE: To evaluate the impact of hypothyroidism in patients undergoing 1- to 2-level lumbar fusion (1-2LF). SUMMARY OF BACKGROUND DATA: Hypothyroidism is a common cause of morbidity and mortality following surgery. Studies have demonstrated the effects of hypothyroidism following orthopedic surgery, but not 1-2LF. MATERIALS AND METHODS: Patients undergoing 1-2LF with hypothyroidism were identified within the Medicare population, and served as the study group. Study group patients were randomly matched to controls in a 1:5 ratio by age, sex, and medical comorbidities. Primary outcomes analyzed included in-hospital lengths of stay (LOS), 90-day readmission rates, 90-day medical complications, and costs of care. Pearson χ tests were used to compare patient demographics. Logistic regression analyses were used to calculate odds ratios (OR) for medical complications and readmissions. Welch t test was used to test for significance in cost between the cohorts. An α value <0.002 was considered statistically significant. RESULTS: The query yielded 417,483 patients who underwent 1-2LF with (n=69,584) and without (n=347,899) hypothyroidism. Hypothyroid patients had significantly longer in-hospital LOS (8 vs. 4 d; P<0.0001) compared with controls. In addition, study group patients had significantly higher incidence and odds of 90-day readmissions (20.22% vs. 17.62%; OR, 1.18; P<0.0001) and 90-day medical complications (6.38% vs. 1.89%; OR, 3.53; P<0.0001) compared with controls. Study group patients had higher day of surgery costs ($97,304.01 vs. $95,168.35; P=0.014) and 90-day costs of care ($113,514.15 vs. $108,860.60; P=0.0001) compared with controls. CONCLUSIONS: After adjusting for age, sex, and medical comorbidities, the study demonstrates patients who have hypothyroidism have longer in-hospital LOS and higher rates of readmissions, complications, and costs. The study is vital as it can allow orthopedic surgeons to adequately counsel and educate these patients of the potential complications that may occur following their procedure.

Cementless Fixation for Total Knee Arthroplasty in Various Patient Populations: A Literature Review.

The number of total knee arthroplasties (TKAs) performed in the United States has increased considerably in recent years, with a major contribution from younger patients. Maximizing survivorship of these implants has always been a point of emphasis. Early TKA designs with cementless fixation were associated with high rates of complications and implant failures. However, recent advances in cementless designs have shown excellent results. The decision to use cemented or cementless fixation for patients undergoing TKA is typically based on the surgeon's experience and preference. However, several patient characteristics must also be taken into account. The purpose of this review was to describe the clinical outcomes of studies in which a cementless TKA system was utilized for patients who (1) were less than 60 years of age, (2) were greater than 75 years of age, (3) were obese, (4) had rheumatoid arthritis, and (5) had osteonecrosis of the knee. Based on the studies included in this review, it appears that cementless fixation is a viable option for patients who have all of the above demographics.

Newer Generation of Cementless Total Knee Arthroplasty: A Systematic Review.

INTRODUCTION: Although the use of cementless implants in total knee arthroplasty (TKA) has increased in recent years, there is still ongoing debate regarding the optimal method of fixation. The purpose of this review was to evaluate the evidence regarding cementless versus cemented total knee arthroplasty (TKA) with regard to: (1) all-cause survivorship and aseptic survivorship; and (2) patient-reported outcome measures (PROMs) of newer generation TKAs. MATERIALS AND METHODS: A systematic review of all reports on cementless TKA published from January 2010 to February 2019 was performed. A total of 221 articles were evaluated and 39 studies met inclusion criteria for final analysis. Metrics evaluated included all-cause survivorship, aseptic survivorship, and Knee Society Scores (KSS). RESULTS: Modern cementless TKA provides excellent survivorship and patient-reported outcomes as compared to cemented designs. CONCLUSIONS: Recent studies have demonstrated that newer generation cementless TKAs provide similar functional outcomes and survivorship as compared to cemented TKA. However, additional prospective, randomized trials with long-term follow up are necessary to further compare the outcomes of cementless versus cemented TKA.

Benefits of CT Scanning for the Management of Hip Arthritis and Arthroplasty.

INTRODUCTION: Imaging studies for preoperative planning of total hip arthroplasty (THA) are typically obtained by two-dimensional (2D) anteroposterior radiographs. However, CT imaging has proven to be a valuable tool that may be more accurate than standard radiographs. The purpose of this review was to report on the current literature to assess the utility of CT imaging for preoperative planning of THA. Specifically, we assessed its utility in the evaluation of: 1) hip arthritis; 2) femoral head osteonecrosis; 3) implant size prediction; 4) component alignment; 5) limb length evaluation; and 6) radiation exposure. MATERIALS AND METHODS: A literature search was performed using search terms "computed tomography", "radiograph", "joint" "alignment", "hip," and "arthroplasty". Our initial search returned a total of 562 results. After applying our criteria, 26 studies were included. RESULTS: CT scans were found to be more accurate than radiographs in predicting implant size and alignment preoperatively and provide improved visualization of extraarticular deformities that may be essential to consider when planning a THA. Although radiation is a potential concern, newer imaging protocols have minimized the radiation to levels comparable to x-ray. CONCLUSION: The current literature suggests that CT has several advantages over radiographs for preoperative planning of THA including more accurate planning of implant size, component alignment, and postoperative leg length. It is also superior to x-ray in identifying extraarticular hip deformities using the minimum effective dose for CT and the minimum scan length required by templating software. The radiation can be reduced to values similar to radiography.

Joint Preservation Procedures for Osteonecrosis.

Osteonecrosis of the femoral head is characterized by reduced intraosseous blood flow to the subchondral bone. The management of early osteonecrosis usually involves joint preservation procedures to provide pain relief, prevent disease progression, and avoid joint replacement. A thorough clinical evaluation is crucial to identify at-risk patients and allow early intervention with joint preservation. The decision to use one joint preserving method over another is dependent on staging and patient characteristics. Surgeons should have a thorough understanding of the available joint preservation procedures to help determine the optimal treatment modality for their patients.