Patient Reported Outcomes After Conversion vs. Primary Total Hip Arthroplasty: A Propensity Matched Analysis

BackgroundConversion total hip arthroplasty (cTHA) is increasingly utilized as a salvage procedure for complications associated with fracture fixation around the hip and acetabulum and for failed hip preservation surgery. While primary THA (pTHA) has a high success rate, little is known about outcomes following conversion THA. The purpose of this study is to evaluate patient reported outcomes (PROs) and complication rates following conversion THA compared to primary THA.MethodsPatients that underwent cTHA or pTHA from 2015-2020 at a large tertiary referral academic center were retrospectively identified. THA patients were propensity matched in a 1:1 fashion by age, body mass index (BMI), and sex. Pain scores and PROMIS physical function (PF), pain interference (PI), and depression (DA) scores were compared at preoperative and final postoperative follow up timepoints using independent t-tests. Differences in complication and reoperation rates between cohorts were assessed using chi square analysis.ResultsA total of 118 THAs (59 cTHA, 59 pTHA) were included in this analysis with an average follow up of 21.3 months. cTHAs were most commonly performed following hip fracture fixation (50.8%). The conversion cohort had significantly longer lengths of stay (3.6 days vs 1.9 days, p<0.01) and greater use of revision-type implants (39.0% vs 0.0%, p<0.01) compared to pTHA. There was no significant difference in complication rates (cTHA = 15.3%, pTHA = 8.5%; p=0.26), with intraoperative fracture being the most common for both. Primary and conversion THA groups also experienced similar reoperation rates (cTHA = 5.1%, pTHA = 6.8%; p=0.70). No significant differences in PROs at final follow up were identified between groups.ConclusionPatients undergoing cTHA required increased utilization of revision hip implants and had longer lengths of stay, but had comparable complication and reoperation rates, and ultimately demonstrated similar improvements in PROMIS scores compared to a matched cohort of pTHA patients. Level of Evidence: III     

Operative Time and Risk of Surgical Site Infection and Periprosthetic Joint Infection: A Systematic Review and Meta-Analysis

BackgroundThe purpose of this study was to perform a systematic review and meta-analysis on the association between operative time and peri-prosthetic joint infection (PJI) after primary total hip arthroplasty (THA) and total knee arthroplasty (TKA).MethodsPubMed, Embase, and Cochrane CENTRAL databases were searched for relevant articles dating 2000-2020. Relationship of operative time and PJI rate in primary total joint arthroplasty (TJA) was evaluated by pooled odds ratios (OR) and 95% confidence intervals.ResultsSix studies were identified for meta-analysis. TJA lasting greater than 120 minutes had greater odds of PJI (OR, 1.63 [1.00-2.66], p=0.048). Similarly, there were greater odds of PJI for TJA procedures lasting greater than 90 minutes (OR, 1.65 [1.27-2.14]; p<0.001). Separate analyses of TKA (OR, 2.01 [0.76-5.30]) and THA (OR, 1.06 [0.80-1.39]) demonstrated no difference in rates of PJI in cases of operative time ≥ 120 minutes versus cases < 120 minutes (p>0.05 for all). Using any surgical site infection (SSI) as an endpoint, both TJA (OR, 1.47 [1.181.83], p<0.001) and TKA (OR, 1.50 [1.08-2.08]; p=0.016) procedures lasting more versus less than 120 minutes demonstrated significantly higher odds of SSI.ConclusionFollowing TJA, rates of SSI and PJI are significantly greater in procedures ≥120 minutes in duration relative to those < 120 minutes. When analyzing TKA separately, higher rates of SSI were observed in procedures ≥ 120 minutes in duration relative to those <120 minutes. Rates of PJI in TKA or THA procedures alone were not significantly impacted by operative time. Level of Evidence: V     

Differences in Infection Rates by Surgical Approach in Total Hip Arthroplasty and Patient Sex: A Systematic Review

BackgroundThere exists conflicting data that patient sex may influence complication and revision rates when undergoing total hip arthroplasty (THA), specifically when comparing different surgical approaches. Differences in body fat or muscular distribution are proposed mechanisms, but these are poorly understood and not well described in current literature.MethodsA systematic review of the literature was conducted from PubMed, Embase, and Web of Science from inception of the database through September 15, 2020. Studies were included if they included patients undergoing primary elective unilateral THA, delineated infections by surgical approach, and delineated infections by patient sex. Basic science, cadaveric, and animal studies were excluded as were case reports. Two authors screened abstracts and then extracted data from the full text article.ResultsThree studies, including 1,694 patients undergoing 1,811 THA were included. 80 infections were included. No study reported a statistically significant difference in infection risk by patient sex or surgical approach, though there was substantial heterogeneity in study design, approach, and analysis.ConclusionLimited data suggests no relationship between sexes across surgical approaches for infection rates. However, poor reporting and small sample sizes preclude definitive conclusions from being drawn. Future studies should emphasize reporting differences in outcomes by patient sex to better elucidate differences, if any, in adverse outcomes between sexes following THA across surgical approaches. Level of Evidence: IV     

Resident Participation During Revision Total Knee Arthroplasty Is Not Associated With Increased Risk of 30-Day Postoperative Complication

BackgroundAcademic teaching institutions perform approximately one third of all orthopedic procedures in the United States. Revision total knee arthroplasty (rTKA) is a complex and challenging procedure that requires expertise and extensive planning, however the impact of resident involvement on outcomes is poorly understood. The aim of the study was to investigate whether resident involvement in rTKA impacts postoperative complication rates, operative time, and length of hospital stay (LOS).MethodsThe American College of Surgeons National Surgical Quality Improvement Program registry was queried to identify patients who underwent rTKA procedures from 2006-2012 using CPT codes 27486 and 27487. Cases were classified as resident involved or attending only. Demographics, comorbidities, and 30-day postoperative complications were analyzed. Multiple logistic regression analysis was performed to identify independent risk factors for increased 30-day postoperative complications. Wilcoxon rank sum tests were performed to determine the impact of resident involvement on operative time and LOS with significance defined as p<0.05.ResultsIn total, 2,396 cases of rTKA were identified, of which 972 (40.6%) involved residents. The two study groups were similar, however the resident involved cohort had more patients with hypertension and ASA class 3 (p=0.02, p=0.04). There was no difference in complications between the cohorts (No Resident vs Resident-involved: 7.0% vs 6.7%, p=0.80). Multivariate analysis identified obesity (OR: 1.81, 95% CI: 1.18-2.79, p=0.01), morbid obesity (OR: 1.66, 95% CI: 1.09-2.57, p=0.02), congestive heart failure (OR: 5.97, 95% CI: 1.19-24.7, p=0.02), and chronic prosthetic joint infection (OR: 3.16, 95% CI: 2.184.56, p<0.01), as independent risk factors for 30-day complications after rTKA. However, resident involvement was not associated with complications within 30-days following rTKA (OR: 0.91, 95% CI: 0.65-1.26, p=0.57). Resident involvement was associated with increased operative time (p<0.001) and LOS (P<0.001).ConclusionResident involvement in rTKA cases is not associated with an increased risk of 30-day postoperative complications. However, resident operative involvement was associated with longer operative time and length of hospital stay. Level of Evidence: III     

Longer Length of Stay Is Associated With More Early Complications After Total Knee Arthroplasty

BackgroundLength of stay (LOS) following total knee arthroplasty (TKA) has decreased over recently years. In 2018, the Centers for Medicare and Medicaid Services removed TKA from Inpatient-Only List (IPO), incentivizing further expansion of outpatient TKA. However, many patients may still require postsurgical hospitalization. The purpose of this study was to assess early outcomes for TKA based on length of stay (LOS).MethodsWe identified patients undergoing elective, primary TKA in the National Surgical Quality Improvement Program database using CPT code 27447 between 2015 and 2018. Patients were stratified by length of stay (LOS) 0 days, 1-2 days, and ≥3 days. Thirty-day rates of any complication, wound complications, readmission, and reoperation were assessed. Multivariate analysis was performed to adjust for confounding variables.Results5,655 (3%) patients underwent outpatient TKA, 130,543 (59%) had LOS 1-2 days, and 84,986 (38%) had LOS ≥3 days. Any complication was experienced in 4.1% of those with LOS 0 days, 4.3% for those with LOS of 1-2 days, and 10.5% for patients with LOS ≥3 days (p<0.0001). Readmission occurred in 2.2%, 2.6%, and 4.0% for the 3 groups, respectively (p<0.0001). After multivariate analysis, there was no significant difference in any outcome measure between patients with LOS 0 and 1-2 days, however those with LOS ≥3 days had higher odds of complications, reoperation, and readmission.ConclusionA significant number of patients had LOS ≥3 days following TKA and had more comorbidities and complications. Outpatient TKA was not associated with increased early complication compared to those with LOS of 1-2 days. Despite expansion of outpatient surgery, postsurgical hospitalization remains an integral part of care following TKA. Level of Evidence: III     

Serum kinetics of soluble triggering receptor expressed on myeloid cells-1 differs in relation to the type of arthroplasty

Context: Soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) participates in the inflammatory process.

Purpose: To describe changes of sTREM-1 in the serum after hemiarthroplasty (HA) and total hip arthroplasty (THA).

Methods: Serial blood samples were drawn from 122 patients with hip fracture. Interleukin-6 (IL-6), sTREM-1, and C-reactive protein (CRP) were measured.

Results: IL-6 and CRP were similarly increased after both HA and THA. sTREM-1 was increased early in HA and late after THA. The only parameter that was higher among patients who developed systemic inflammatory response syndrome was IL-6.

Conclusions: Kinetics of sTREM-1 differs among patients undergoing HA of the hip and those undergoing THA.     

Evaluating the Association between Anesthesia Type and Postoperative Complications for Patients Receiving Total Ankle Arthroplasty

BackgroundTotal ankle arthroplasty (TAA) is performed for ankle arthritis and there has been interest investigating which anesthetic method is the best choice in order to optimize perioperative outcomes. In this study, we compared postoperative complications after TAA for patients receiving either 1) general anesthesia alone or 2) general anesthesia plus regional anesthesia.MethodsPatients undergoing primary TAA from 2007 to 2018 were identified in a national database. Patients were stratified into 2 cohorts: general anesthesia and general anesthesia combined with regional anesthesia. In this analysis, 30-day wound, cardiac, pulmonary, renal, thromboembolic, and sepsis complications, as well mortality, postoperative transfusion, urinary tract infection, extended length of stay, and reoperation were assessed. Bivariate analyses and multivariable logistical regression were performed.ResultsOf 1,084 total patients undergoing TAA, 878 patients (81.0%) had general anesthesia and 206 (19.0%) had general anesthesia combined with regional anesthesia. Following adjustment, there were no increased risk of postoperative complications in the combined general and regional anesthesia group compared to those who only underwent general anesthesia.ConclusionCompared to general anesthesia alone, the addition of regional anesthesia to general anesthesia for TAA is not associated with increased risk of complications in the perioperative period. Level of Evidence: III     

Total Hip Arthroplasty: Direct Anterior Approach Versus Posterior Approach in the First Year of Practice

BackgroundThe direct anterior approach (DAA) for total hip arthroplasty (THA) has been popularized as a less invasive technique, however outcomes within the first year of practice after fellowship have not been investigated. The primary aim was to determine differences in complications and outcomes between DAA and posterior approach (PA) in the first year of practice. The secondary aim was to determine if there was a learning curve factor in DAA and PA after fellowship training.MethodsTHA cases performed by two surgeons during their first year of practice were reviewed. Overall, 181 THAs (91 DAA, 90 PA) in 168 patients, were performed. Intraoperative differences (blood loss, operative time), hospital stay, complications, reoperations, and revisions were compared.ResultsOverall surgical complications were similar between DAA and PA (11% vs. 9%, p=0.64), but complication profiles were different: dislocation (1% vs. 4%, p=0.17), intraoperative femoral fracture (2% vs. 1%, p=0.32), postoperative periprosthetic fractures (2% vs. 3%, p=0.64). neuropraxia (3% vs. 0%, p=0.08). There was no difference in rate of reoperation (1% vs. 3%, p=0.31). There was a difference in rate of revision at final follow-up (0% vs. 6%, p=0.02). DAA consisted of longer operative time (111 vs. 99 minutes; p<0.001), however was only significant in the first 50 cases (p<0.001), while the subsequent cases were similar (p=0.31). There was no difference in the first 50 cases compared to the subsequent cases for either approach regarding blood loss, complications, reoperations, or revisions.ConclusionDAA and PA for THA performed within the first year of practice exhibit similarly low complication rates, but complication profiles are different. In our series, PA did demonstrate a higher risk of revision at final follow-up. A learning curve is not unique to the DAA. Both DAA and PA THA exhibited a learning curve in the first 50 cases performed at the start of a surgeon’s practice. Level of Evidence: III     

早期下床活动联合髋部周围肌肉抗阻训练对老年全髋关节置换术后患者髋关节功能和生活质量的影响

摘要 目的：观察早期下床活动联合髋部周围肌肉抗阻训练对老年全髋关节置换术（THA）后患者髋关节功能和生活质量的影响。方法：选取我院2018年2月~2020年8月期间收治的老年THA患者83例。使用随机数字表法将患者分为对照组和联合组,例数分别为41例和42例,分别接受早期下床活动、早期下床活动联合髋部周围肌肉抗阻训练干预,对比两组睡眠质量、疼痛情况、生活自理能力、术后多个时点的髋关节功能评分、生活质量,并观察两组并发症发生情况。结果：两组干预后匹兹堡睡眠质量指数（PSQI）、视觉模拟评分法（VAS）评分较干预前下降,Barthel指数（BI）评分较干预前升高,且联合组的变化程度大于对照组（P<0.05）。两组术后1个月、3个月、6个月、12个月Harris人工髋关节功能评分逐渐升高,且联合组高于对照组（P<0.05）。两组干预后心理功能、物质生活状态、社会功能、躯体功能评分较干预前升高,且联合组的变化程度大于对照组（P<0.05）。两组并发症发生率组间对比无统计学差异（P>0.05）。结论：早期下床活动联合髋部周围肌肉抗阻训练可促进老年THA后患者髋关节功能恢复,减轻患者术后疼痛,改善睡眠质量,进而提高患者的生活质量,预防相关并发症的发生,改善预后。     

直接前方入路与直接外侧入路人工全髋关节置换术的临床效果比较研究

目的:探讨平卧位直接前方入路(DAA)与侧卧位直接外侧入路(DLA)对行初次全髋关节置换术(THA)患者髋关节功能、平衡功能和步态参数的影响。方法:选取2018年2月～2019年10月期间我院收治的初次THA患者97例,根据入路方式的不同随机分为A组(n=47)和B组(n=50),A组行侧卧位DLA,B组行平卧位DAA,比较两组髋关节功能、影像学参数、平衡功能和步态参数,记录两组术后并发症发生率。结果:术后1周、1个月、3个月及6个月两组髋关节Harris评分(HHS)、Berg平衡量表评分(BBS)依次升高,且B组高于A组(P0.05)。B组手术时间长于A组,术中出血量少于A组,切口长度、初次下床行走时间短于A组(P0.05)。术后3个月、6个月两组步频、步速、步长依次升高,且B组高于A组(P0.05)。两组并发症发生率对比,组间比较未见统计学差异(P0.05)。两组术后6个月髋臼假体外展角、前倾角对比,组间比较无显著差异(P0.05)。结论:与侧卧位DLA相比,初次THA患者行平卧位DAA可获得与其相当的手术效果,同时能更好地改善患者髋关节功能、平衡功能和步态,且安全性有保障。     

术前糖化血红蛋白水平与老年髋关节置换术后谵妄的关系研究

摘要 目的：探讨术前糖化血红蛋白（HbAlc）水平与老年髋关节置换术后谵妄的关系,并分析术后发生谵妄的影响因素。方法：选择我院于2019年4月~2020年6月期间收治的行髋关节置换术的220例老年患者作为研究对象。收集患者临床资料,记录其术后发生谵妄情况。采用单因素及多因素Logistic回归分析术后发生谵妄的影响因素。采用Pearson相关分析评估患者术前HbAlc水平与术后意识障碍评估量表（CAM）评分的相关性。结果：220例患者根据剔除标准剔除20例,最终200例老年髋关节置换术后患者出现谵妄42例,发生率为21.00%（42/200）。将发生谵妄的患者纳为谵妄组（n=42）,未发生谵妄的患者纳为非谵妄组（n=158）。谵妄组的术前HbAlc水平、术后CAM评分均高于非谵妄组（P<0.05）。Pearson相关分析显示,患者术前HbAlc水平与术后CAM评分呈正相关（P<0.05）。单因素分析结果显示,老年髋关节置换术后发生谵妄与年龄、术前合并呼吸系统性疾病、手术时间、发生低氧血症、术后疼痛评分、存在电解质紊乱有关（P<0.05）,多因素Logistic回归分析结果显示,年龄>80岁、发生低氧血症、术后疼痛评分＞3分、术前HbAlc水平＞8%均是老年髋关节置换术后发生谵妄的危险因素（P<0.05）。结论：高龄、术前HbAlc水平较高的患者是髋关节置换术后发生谵妄的高危人群,且围术期应尽量给予减少疼痛、预防术后低氧血症的措施,以降低术后谵妄的发生风险。     

术中保温联合早期系统化康复训练对老年全髋关节置换术患者凝血功能、康复效果和生活质量的影响

摘要 目的：观察术中保温联合早期系统化康复训练对老年全髋关节置换术（THA）患者凝血功能、康复效果和生活质量的影响。方法：选择我院2018年8月～2021年8月期间收治的80例老年THA患者,按随机数字表法将其分为对照组（40例）和观察组（40例）。对照组患者接受早期系统化康复训练,观察组患者接受术中保温联合早期系统化康复训练,对比两组术中低体温发生率、凝血功能、康复效果和生活质量。结果：观察组的术中低体温发生率明显低于对照组（P<0.05）。观察组的下床活动时间、住院时间短于对照组（P<0.05）。两组术后8周Harris髋关节功能评分均升高,且观察组高于对照组（P<0.05）。对照组术后7 d凝血酶原时间(PT) 、活化部分凝血活酶时间( APTT) 及凝血酶时间( TT) 、纤维蛋白原（FIB）均升高（P<0.05）,观察组术前、术后7 d PT、APTT、TT、FIB组内对比无统计学差异（P>0.05）,观察组术后7 d PT、APTT、TT、FIB低于对照组（P<0.05）。对照组术后6个月躯体职能、角色职能、情绪职能、认知职能、社会职能评分升高,且观察组高于对照组（P<0.05）。结论：术中保温联合早期系统化康复训练可促进老年THA患者康复,有效保护机体凝血功能,促进患者生活质量提高,效果显著。     

Similar Outcomes Achieved Between Anterior and Posterior Approach Total Hip Arthroplasty Using Dual Mobility Implants

BackgroundDual mobility (DM) bearings for total hip arthroplasty (THA) have been proposed to reduce the risk of instability in high-risk patients; however, their utility in primary THA remains relatively unexplored. No previous reports have described whether surgical approach influences outcomes associated with DM implant systems. This study aims to compare patient reported outcomes and post-operative groin pain between patients undergoing anterior approach versus posterior approach following primary THA with DM implants.MethodsWe retrospectively reviewed all patients who underwent primary THA and received a DM implant between 2011-2021. Patients were stratified into two cohorts based on surgical approach (anterior vs. posterior approach). Primary outcomes included the presence of substantial postoperative groin pain as well as readmission and revision rates. Demographic differences were assessed using chi-square and independent sample t-tests. Outcomes were compared using multilinear and logistic regressions.ResultsOf the 495 patients identified, 55 (11%) underwent THA via the anterior approach and 440 (89%) via the posterior approach. Surgical time (100.24 vs. 109.42 minutes, p=0.070), length of stay (2.19vs.2.67 days,p=0.072), discharge disposition (p=0.151), and significant postoperative groin pain (1.8%vs.0.7%,p=0.966) did not statistically differ between the cohorts. 90-day readmission (9.1%vs.7.7%,p=0.823) and revision rate (0.0%vs.3.0%,p=0.993) did not significantly differ as well. Specifically, readmission (p=0.993) and revision (p=0.998) for instability did not significantly differ between the cohorts. We found no statistical difference in HOOS, JR (p=0.425), VR-12 PCS (p=0.718), and VR-12 MCS (p=0.257) delta score improvement from preoperative to 1-year follow-up between the two groups.ConclusionComparable outcomes following implantation of DM constructs may be achievable irrespective of the surgical approach employed. The incidence of iliopsoas injections for groin pain did not significantly differ between anterior and posterior approaches. Future investigation is needed to determine whether surgical approach influences long-term outcomes in patients receiving DM implants. Level of Evidence: III     

不同入路人工全髋关节置换术对髋关节疾病患者康复进程、髋关节功能和生活质量的影响

目的:探讨不同入路人工全髋关节置换术(THA)对髋关节疾病患者康复进程、髋关节功能和生活质量的影响。方法:回顾性分析2016年4月～2018年11月期间到我院行THA治疗的髋关节疾病105例患者的临床资料。根据入路方式的不同将其分为A组(n=54,后外侧入路)和B组(n=51,SuperPATH入路),术后行1年的随访,比较两组患者康复进程、髋关节功能和生活质量,记录两组术后并发症发生情况。结果:B组术中失血量、术后引流量少于A组,切口长度、术后第一次下地时间短于A组(均P0.05);B组手术时间长于A组(P0.05)。两组术后1个月、3个月、6个月、12个月髋关节屈曲活动度、髋关节功能Harris评分、髋关节外展活动度均较术前呈先升高后趋于平稳趋势(P0.05);B组术后1个月髋关节屈曲活动度及外展活动度、髋关节功能Harris评分高于A组(P0.05);B组术后3个月、6个月、12个月髋关节屈曲活动度及外展活动度、髋关节功能Harris评分与A组比较无差异(P0.05)。两组末次随访时SF-36各维度评分均较术前升高,且B组高于A组(P0.05)。两组术后并发症发生率比较无差异(P0.05)。结论:与后外侧入路方式相比,髋关节疾病患者THA中采用SuperPATH入路,可促进患者早日康复,有利于患者早期髋关节功能的恢复,对生活质量的改善更为显著,且不增加并发症发生率。     

The Cost-Effectiveness of Reverse Total Shoulder Arthroplasty Versus Open Reduction Internal Fixation for Proximal Humerus Fractures in the Elderly

BackgroundOpen reduction and internal fixation (ORIF) of proximal humerus fractures in elderly individuals (age >70) carries a relatively high short-term complication and reoperation rate but is generally durable once healed. Reverse total shoulder arthroplasty (RTSA) for fractures may be associated with superior short-term quality of life but carries the lifelong liabilities of joint replacement. The tradeoff between short and long-term risks, coupled with disparities in quality of life and cost, makes this clinical decision amenable to cost-effectiveness analysis.Methods A Markov state-transition model was constructed with a base case of a 75 year-old patient. Reoperation rates, quality of life values, mortality rates, and costs were based upon published literature. The model was run until all patients had died to simulate the accumulated costs and benefits.ResultsRTSA was associated with greater quality of life (7.11 QALYs) than ORIF (6.22 QALYs). RTSA was cost-effective with an incremental cost-effectiveness ratio of $3,945/QALY and $27,299/ QALY from payor and hospital perspectives, respectively. RTSA was favored and cost-effective at any age above 65 and any Charlson Score. The model was sensitive to the utility of both proceduresConclusionRTSA resulted in a higher quality of life and was cost-effective in comparison to ORIF for elderly patients.Level of Evidence: III     

The effects of manufacturing tolerances and assembly force on the volumetric wear at the taper junction in modular total hip arthroplasty

Abstract

Fretting and corrosion at the taper-head interface in total hip arthroplasty has been reported as a potential cause of early failure of the implant system. The finite element (FE) method can be used to study the mechanics at the taper junction that are difficult to assess experimentally. Taper mismatch is one of the factors that can influence the performance of the taper junction. In this study we have assessed the effect of taper mismatch, in combination with assembly force on the volumetric wear. The study showed that higher assembly forces and smaller mismatches result in the least volumetric wear.     

Is There a Time-Dependent Contamination Risk to Open Surgical Trays During Total Hip and Knee Arthroplasty?

BackgroundPeriprosthetic joint infection (PJI) after total hip and knee arthroplasty (TJA) is a devastating complication and intraoperative contamination can be a source for PJI. Currently, many measures are performed intraoperatively to reduce the risk of contamination. The primary purpose of this study was to determine if there is a time-dependent risk of contamination to open sterile surgical trays during TJA cases.MethodsA prospective intraoperative culture swab study was performed. Standard sterile operating room trays without instruments were utilized as the experimental trays. These were opened simultaneously with all other surgical instrumentation needed for the procedure. These trays were left on an isolated Mayo stand next to the scrub tech’s table and swabbed at 30-minute intervals. The first swab was performed immediately after opening all sets and the last swab performed on closure of the incision. A new section of the grid-lined tray was swabbed for each data point and the culture analysis was conducted by our institutions’ microbiology lab for both quantitative and qualitative analysis. Operating suite room temperature and humidity data was also gathered.ResultsTwenty-three consecutive primary TJA cases in high air turnover rooms were included. 13 of the 23 (57%) cases demonstrated culture positive bacterial growth on at least one time point. Of the 109 independent swabs collected, 19 (17%) had bacterial growth. The most common bacterial species isolated was Staphylococcus epidermidis. There were no statistically significant associations between time (p= 0.35), operating room (OR) temperature (p = 0.99), and OR humidity (p = 0.07) and with bacterial growth.ConclusionIn spite of isolating an organism in 57% of cases, we could not identify a time-dependent increase in bacterial contamination throughout our operative cases. We were unable to associate OR environmental temperature and humidity to bacterial growth. Level of Evidence: II     

Defining the Relationship between Obesity and Total Joint Arthroplasty

Objective: The purpose of this study was to examine the relationship between obesity and patient‐administered outcome measures after total joint arthroplasty. Research Methods and Procedures: A voluntary questionnaire‐based registry contained 592 primary total hip arthroplasty patients and 1011 primary total knee arthroplasty patients with preoperative and 1‐year data. Using logistic regression, the relationships between body mass index and the several outcome measures, including Short Form‐36 and Western Ontario and McMaster Universities Osteoarthritis Index, were examined. Results: There was no difference between obese and non‐obese patients regarding satisfaction, decision to repeat surgery, and Δphysical component summary, Δmental component summary, and ΔWestern Ontario and McMaster Universities Osteoarthritis Index scores (p > 0.05 for all). Body mass index was associated with an increased risk of having difficulty descending or ascending stairs at 1 year (odds ratio, 1.2 to 1.3). Discussion: Obese patients enjoy as much improvement and satisfaction as other patients from total joint arthroplasty.     

News in Brief

Total hip and knee arthroplasties are commonly performed orthopedic procedures that involve a complex interaction between the prosthetic device and its surrounding biological environment. Recent developments in the field of proteomics have enabled a better understanding of these interactions in patients with a total joint arthroplasty and have the potential to lead to development of novel diagnostic and therapeutic modalities that may improve the care of these patients, particularly those who have developed complications of wear, osteolysis, loosening and periprosthetic joint infection. This article reviews several of the areas of active research that are occurring at the intersection of the fields of proteomics and total joint arthroplasty.