Complications Of Total Shoulder Arthroplasty Research Articles

Bariatric surgery patients have 5-year risk of revision following total shoulder arthroplasty comparable to that of class III obesity patients

BackgroundObesity has been correlated with heightened risk of complications after orthopedic surgeries. Bariatric surgery (BS) is an effective tool commonly utilized for the reduction of body mass index. However, the impact of BS on complications in total shoulder arthroplasty (TSA) remains inadequately investigated. This study examines the 5-year risk of revision following TSA in patients with a history of BS compared to matched cohorts without history of BS. MethodsUtilizing the PearlDiver Mariner database, a retrospective cohort analysis was conducted on over 157 million U.S. patients from January 2010 to October 2021. Inclusion criteria identified patients undergoing primary TSA with a minimum 2-year follow-up. Propensity-score matching was employed to control for covariates, comparing BS patients with a matched control and a matched class III obesity control without history of BS. Demographics, comorbidities, and outcomes, including 5-year cumulative incidence of revision were analyzed. ResultsThe 5-year cumulative incidence of all-cause revision within the BS group was found to be 4.6%. While this represented a higher risk than that of the general population (hazard ratio 1.70; 95% confidence interval 1.21-2.39), there was no significant difference when compared to controls with class III obesity. The BS cohort had higher risk of revision secondary to dislocation/subluxation and rotator cuff tear than in the general population. When compared to the class III obesity cohort, only the risk of revision due to rotator cuff tear was found to be higher. ConclusionIndividuals with a history of BS showed a higher risk of revision than a cohort without history of BS and an equivalent risk of revision compared to a cohort of class III obesity controls after undergoing TSA. Though obesity is an important risk factor for complications after TSA, BS might not be an effective tool for preoperative risk optimization.

The association of alcohol use disorder with revision rates and post-operative complications in total shoulder arthroplasty.

Alcohol use disorder (AUD) is the most prevalent substance use disorder in the United States. However, the current literature on AUD as a preoperative risk factor for Total Shoulder Arthroplasty (TSA) outcomes is limited. The purpose of this study was to identify the association of AUD with revision rates and 90-day postoperative complications in TSA. A retrospective study was conducted using the PearlDiver database. Patients diagnosed with AUD were identified. Patients in remission or with underlying cirrhosis were excluded. Outcomes included 2-year revision, 90-day readmission, 90-day emergency, and 90-day post-operative medical complications. Analysis was performed with univariate chi-squared tests followed by multivariable logistic regression. A total of 59,261 patients who underwent TSA for osteoarthritis were identified, with 1522 patients having a diagnosis of AUD. Multivariable logistic regression showed that patients with AUD were more likely to undergo 2-year all-cause revision (OR = 1.49, p = 0.007), 2-year aseptic revision (OR = 1.47, p = 0.014), 90-day hospital readmission (OR = 1.57, p = 0.015), and 90-day transient mental disorder (OR = 2.13, p = 0.026). AUD is associated with increased rates of 2-year revision surgery, as well as 90-day readmission and 90-day transient mental disorder following primary TSA for osteoarthritis. These findings may assist orthopedic surgeons in counseling patients with AUD during the pre-operative course.

A novel comorbidity risk score for predicting postoperative 30-day complications in total shoulder arthroplasty and elucidation of potential racial disparities.

Efficient and effective preoperative identification of those patients with elevated risk may allow for more cost-effective interventions, accurate bundled payment adjustments, and overall improved patient care. Few comorbidity indices have provided clinical utility and adequate discriminative ability in the setting of complications after shoulder arthroplasty (SA). The American College of Surgeons National Surgical Quality Improvement Program database was queried for anatomic and/or reverse SA procedures between 2010 and 2019. A subset of comorbidities were utilized including end-stage renal disease, history of hypertension, chronic obstructive pulmonary disease, functional status, history of bleeding disorder, and disseminated cancer. A total of 25,927 patients with an average age of 69.2 (standard deviation±9.5) years were included in the study. Patients with a comorbidity risk score (CRS) at or above 2 were indicated to have at least a 29.6% 30-day postoperative complication rate after undergoing total shoulder arthroplasty, significantly higher than the described average of approximately 15%. The area under receiver operator curve for the novel CRS scoring system was 0.595, indicating fair discriminative ability to predict 30-day postoperative complications after SA. This illustrates a discriminative ability similar to that of the American Society of Anesthesiologists classification (0.584, confidence interval [CI] 0.578-0.589), modified Charlson Comorbidity Index (0.567, CI 0.561-0.573), and modified Frailty Index (0.534, CI 0.529-0.539), each of which are common comorbidity indices used for the National Surgical Quality Improvement Program database. The average CRS for the population was 0.8537 (CI 0.8011-0.8150; P<.05) while that for the Black demographic was 1.08 (CI 1.03-1.13; P<.001). Our results suggest that if the disparity in CRS among races was corrected, the average complication rate would be decreased by 2.0%. A higher CRS score resulted in higher rates of 30-day postoperative complications following SA. Black patients had a higher average CRS than all other races illustrating a racial disparity in comorbidity risk. Although the average complication rate of each race would still be unequal, this could mitigate some of the racial disparities observed and decrease the overall 30-day complication rate in SA. With the rise of bundled payments further increasing the need to preoperatively identify patients at high risk for costly complications, the CRS is based on easily identified, relevant comorbidities that may be an advantageous tool to identify patients at increased risk of complications following SA.

Venous Thromboembolism After Total Shoulder Arthroplasty: A Database Study of 31,918 Cases.

Venous thromboembolism (VTE), including pulmonary embolism (PE) and deep vein thrombosis (DVT), is a rare but serious complication of total shoulder arthroplasty (TSA). Owing to limited evidence, Clinical Practice Guideline recommendations for VTE chemoprophylaxis after TSA rely heavily on the risk stratification of individual patients. The objectives of this study were to identify the prevalence and risk factors independently associated with VTE, PE, and DVT in the 30-day postoperative period after TSA. A retrospective case-control study was conducted using the American College of Surgeons National Surgical Quality Improvement Program database by querying the Current Procedural Terminology code for total shoulder arthroplasty from 2011 to 2020. The initial query resulted in 33,089 patients. After applying exclusion criteria for age younger than 50 years, emergency surgery, and open wound or infection, a final cohort of 31,918 patients who underwent TSA were included. The primary outcome was venous thromboembolism, and secondary outcome variables were PE and DVT. A bivariate screen was done for explanatory variables associated with our outcome variables, and variables with P < 0.1 in the bivariate screen were included in a multivariable logistic regression model. Of the 31,918 patients in our cohort, 183 patients (0.573%) developed VTE, 92 patients (0.29%) developed PE, and 104 patients (0.326%) developed DVT during the 30-day postoperative period. Multivariable logistic regression analysis showed that older age, higher body mass index, longer surgical time, and longer hospital length of stay were associated with VTE and PE and that hypertension and shorter hospital length of stay were associated with DVT. The prevalence of VTE after TSA is low. Older patients, patients with higher body mass index, and patients with longer surgical durations are at higher risk for VTE after TSA. Our findings are relevant for preoperative risk stratification and the decision for chemoprophylaxis. Level III Prognostic.

Trends in operative duration of total shoulder arthroplasty from 2008 to 2018: a national database study.

As total shoulder arthroplasty has emerged as the fastest growing joint replacement performed, optimizing surgical efficiency and patient outcomes is essential. The goals of the current study were to identify trends and factors affecting the operative time of total shoulder arthroplasty over a 10-year period. The National Surgical Quality Improvement Program database was analyzed to determine the operative time and 30-day complications of total shoulder arthroplasty from 2008 to 2018. Factors affecting total shoulder arthroplasty operative time were also assessed. Multivariable linear regression was used to analyze operative time over years studied while controlling for patient demographics and comorbidities. A total of 20,587 total shoulder arthroplasty cases from 2008 to 2018 were included. Mean operative time in 2008 was 139.0 min, while in 2018, mean operative time decreased to 105.6 min (P < .001). Male sex, outpatient surgery, increased body mass index, and low preoperative hematocrit were associated with longer operative times, while elevated international normalized ratio, resident involvement, and elective surgeries were associated with decreased operative duration. Operative time for total shoulder arthroplasty has decreased from 2008 to 2018. Patient factors and comorbidities are associated with operative time, and such factors are important to consider in operative planning to ensure appropriate patient and surgeon expectations.

The effect of body mass index on one-year functional outcome, quality of life and postoperative complications in total shoulder arthroplasty.

The aim of this retrospective cohort study was to investigate the effect of BMI on 1-year functional outcome, quality of life (QoL) and rate of postoperative complications after shoulder arthroplasty. We included 121 patients (59 men and 62 women) with primary osteoarthritis (OA) who underwent anatomical or reverse total shoulder arthroplasty (TSA or rTSA) between 2011 and 2016. Age, sex, preoperative BMI, preoperative medical status using American score of anesthesiologists (ASA) class, type of prosthesis, preoperative and 1-year postoperative functional outcome using the Constant score and quality of life (QoL) using the EQ-5D as well as postoperative complication rate were documented. Patients were divided into three groups based on their BMI, group 1 (normal weight, BMI <25), group 2 (overweight, BMI 25-30) and group 3 (obese, >BMI 30). All three groups were comparable regarding age, sex and ASA class, preoperative Constant score EQ-5D. We found significant improvement of the Constant score and EQ- 5D at 1-year postoperative follow-up, regardless of BMI (p<0.05). Comparing the three groups, we found no significant differences among them in 1-year Constant score, EQ-5D or postoperative rate of complications. This study showed that BMI did not affect functional outcome, QoL and postoperative complication rate in TSA. These results can help physicians and patients to make reasonable perioperative expectations and planning.

Thermal and cutting dynamics of new and used glenoid reamers during total shoulder arthroplasty*

BackgroundGlenoid loosening is the most common complication of total shoulder arthroplasty (TSA) resulting in revision. Inaccurate reaming and thermal osteonecrosis from heat generated during the reaming process may contribute to TSA failure by creating a suboptimal bone-implant interface for osteointegration. This biomechanical study investigated the differences in depth penetration and heat generation of used community glenoid reamers in comparison to brand new reamers by using a clinically relevant force. MethodsA MTS Servohydraulic machine was utilized to test new and used community glenoid reamers by applying the clinically relevant force of 54.7 N over a defined time. The depth of penetration was measured via the MTS machine and the thermal profile was obtained via an infrared camera. The used reamers were then set by the MTS machine to reach the same depth as the new reamers for all respective sizes while recording the force differential generated and capturing the thermal profile. Levene's F test for variance and a Welch t test for scale variables were performed via SPSS Statistics 24 software. ResultsAt a constant force and time, the new reamers penetrated a greater depth (4.18 ± 2.17 mm) than the community used reamers (0.41 ± 0.22 mm), a difference of 3.80 mm ((95% CI, 2.23 to 5.31 mm), P < .001) without generating temperatures above 50°C. When programmed to reach the same average depth as the new reamers of equivalent sizes, the community reamers generated more heat on average (50.02°C ± 2.88°C), a difference of 5.98°C ((95% CI, 3.40-8.53), P< .001). The used reamers on average also required 218.20 N more force than the new reamers (54.71 ± 28.69 N) to reach the same depth, with the medium (303.47 ± 96.71 N) and large (261.72 ± 55.28 N) reamers specifically requiring the largest amount of force. ConclusionThe sharpness of glenoid reamers varies in the community. In order to reach the necessary depth for adequate fixation of implants, orthopedic surgeons may be required to exert a substantially larger force when using dulled reamers in comparison to sharp reamers. As a consequence, the heat generated could increase the risk of thermal osteonecrosis resulting in glenoid loosening. To minimize these risks, strategies may be employed to measure reamer wear, track reamer usage for exchanges, or develop disposable reamer systems. Level of evidenceBasic Science Study; Biomechanics

Arthroscopic glenoid removal for aseptic loosening in total shoulder arthroplasty

BackgroundGlenoid loosening is the most common long-term complication of total shoulder arthroplasty (TSA) and frequently necessitates revision. Though arthroscopic glenoid removal is an accepted treatment option for glenoid loosening, there is a paucity of outcomes literature available. The purpose of this study was to report the long-term clinical and radiographic outcomes of arthroscopic glenoid removal for failed or loosened glenoid component in TSA. We hypothesized that arthroscopic glenoid removal would produce acceptable clinical and patient-reported outcomes while limiting the need for further revisions. MethodsThis was a retrospective analysis of 11 consecutive patients undergoing 12 arthroscopic glenoid removals for symptomatic glenoid loosening by a single orthopedic surgeon between March 2005 and March 2018. Indication for arthroscopic glenoid removal included symptomatic glenoid loosening with radiographic evidence of a 1-2 mm radiolucent line around the glenoid. Shoulder range of motion, functionality (American Shoulder and Elbow Surgeons, Simple Shoulder Test), and pain (visual analog scale [VAS]) were evaluated. Radiographs were assessed for glenohumeral subluxation, humeral superior migration, and glenohumeral offset following glenoid removal. ResultsThe mean follow-up period since arthroscopic glenoid removal was 55 months (range, 20-172 months). Glenoid component removal significantly reduced forward elevation, with a mean decrease from 147 ± 13° preoperatively to 127 ± 29° postoperatively (P= .031). However, there was no significant change in external rotation (44 ± 9° vs. 43 ± 19°; P= .941) or internal rotation (L4 vs. L4; P= .768). Importantly, glenoid removal significantly decreased VAS pain scores from 7 ± 3 preoperatively to 5 ± 3 postoperatively (P= .037). Additionally, improvement in ASES approached statistical significance, increasing from 33 ± 25 preoperatively to 53 ± 28 postoperatively (P= .055). With regard to radiographic outcomes, there was no evidence of glenohumeral subluxation and humeral superior migration developed in 1 patient. However, there was significant medialization of the greater tuberosity relative to the acromion, with a mean lateral offset of 6 ± 7 mm preoperatively and −2 ± 4 mm postoperatively (P= .002). Two patients required conversion to reverse TSA for persistent pain. There were no complications. DiscussionThese findings suggest that arthroscopic glenoid removal for symptomatic glenoid loosening is a viable option to improve pain while limiting the need for additional reoperations and decreasing the risks associated with revision arthroplasty. However, continual follow-up to monitor medialization is recommended. Level of EvidenceLevel IV; Case Series; Treatment Study

Vitamin D deficiency and total shoulder arthroplasty complications.

The primary objective of this study was to examine the relationship between vitamin D deficiency and implant-related and medical complications following total shoulder arthroplasty. Using the PearlDiver database, patients who underwent total shoulder arthroplasty from 2005 to 2016 with vitamin D deficiency were identified. These were compared to a 3:1 control group matched by age, sex, and presence of a concomitant osteoporosis diagnosis. Primary outcome measures were implant-related complications (loosening, periprosthetic fracture, periprosthetic joint infection, and revision total shoulder arthroplasty) in addition to medical complications within 90 days of surgery. A multivariable logistic regression analysis was utilized to control for patient demographics and comorbidities. One thousand and six hundred and seventy-four patients with vitamin D deficiency were identified and compared to 5022 controls. There was a significantly higher rate of revision total shoulder arthroplasty in the vitamin D deficient patients compared to controls (2.3% versus 0.8%, odds ratio 3.3, p < 0.0001). After controlling for confounding variables, there were no significant differences in any of the remaining implant-related or medical complications with the exception of higher rates of urinary tract infections in patients with vitamin D deficiency. Vitamin D deficiency is associated with a higher rate of all-cause revision total shoulder arthroplasty but not medical complications compared to controls.Level of evidence: Level III case control study.

Posterior Approach Total Shoulder Arthroplasty: A Retrospective Analysis of Short-term Results.

Subscapularis dysfunction and failure are the leading causes of complications of total shoulder arthroplasty (TSA). An approach to shoulder arthroplasty has been described that may improve exposure to the retroverted glenoid and spare the rotator cuff. This article details the 6-month clinical outcomes of the first 26 patients who underwent TSA using a posterior approach. Thirty-one patients who underwent TSA using a posterior approach between September 2016 and October 2017 were identified retrospectively. Patients were assessed for American Shoulder and Elbow Surgeons (ASES) scores, Simple Shoulder Test (SST) scores, range of motion, complications, radiographic outcomes, and patient satisfaction. Statistical models were used to compare the means for each outcome variable over time. Of the initial 31 patients, 26 patients were available for follow-up at a minimum of 6 months; the remaining 5 patients did not return for follow-up at 6 months. Significant improvement in each outcome variable from baseline was noted by 6 weeks postoperatively. Further improvement was observed at 3 months for SST and external rotation, and at 6 months for ASES function and forward flexion. All outcome variables demonstrated some improvement from one time point to the next. Posterior TSA is a safe and efficacious procedure at 6 months. Compared with traditional TSA, posterior cuff-sparing approaches may improve posterior joint access, posterior soft tissue balancing, and long-term rotator cuff issues. [Orthopedics. 2020; 43(1):e15-e20.].

The effect of operative time on early postoperative complications in total shoulder arthroplasty: An analysis of the ACS-NSQIP database.

Total shoulder arthroplasty has been demonstrated to be an effective treatment for arthritis of the glenohumeral joint. Prior studies have identified longer operative times as a risk factor for complications after numerous types of procedures. We hypothesized that increased operative time, in 20-min intervals, would be associated with complications following total shoulder arthroplasty. Patients undergoing total shoulder arthroplasty from 2006 to 2015 were identified from the ACS-NSQIP database. Patient demographic information, perioperative parameters, and 30-day outcomes were retrieved. Pearson's Chi-square test and multivariate Poisson regression with robust error variance were used to analyze the relationship of operative time and outcomes. A total of 10,082 patients were included. Multivariate analysis revealed that for each increase in 20 min of operative time, there were significantly increased rates of any complication (relative risk (RR) 1.24, 95% confidence interval (CI) 1.19-1.26), anemia requiring transfusion (RR 1.33, 95%CI 1.26-1.4), peripheral nerve injury (RR 1.88, 95%CI 1.53-2.31), and urinary tract infection (RR 1.24, 95%CI 1.09-1.41). This study indicates that increasing operative time confers increased risk for postoperative complications following total shoulder arthroplasty. We anticipate the results of this manuscript will be used for provider education, policy decision-making, and potentially to derive algorithms that can improve safety and efficiency in total shoulder arthroplasty. III.

Способы профилактики неудовлетворительных результатов и осложнений при эндопротезировании плечевого сустава

Способы профилактики неудовлетворительных результатов и осложнений при эндопротезировании плечевого сустава

Patients With Chronic Obstructive Pulmonary Disease Are at Higher Risk for Pneumonia, Septic Shock, and Blood Transfusions After Total Shoulder Arthroplasty.

Chronic obstructive pulmonary disease (COPD) has been associated with several complications after surgery, including pneumonia, myocardial infarction, septic shock, and mortality. To the authors' knowledge, there has been no work analyzing the impact of COPD on complications after total shoulder arthroplasty (TSA). Although previous work has elucidated the complications COPD has on TKA and THA, extrapolating the results of lower extremity arthroplasty to TSA may prove to be inaccurate. Compared with lower extremity arthroplasty, TSA is a relatively new procedure that has only recently gained popularity. Therefore, this study seeks to elucidate COPD's effects on complications in TSA specifically so that postoperative care can be tailored for these patient populations. Assessing these patients may enable surgeons to implement preoperative precautionary measures to prevent serious adverse events in these patients. What serious postoperative complications are patients with COPD at risk for within the 30-day postoperative period after TSA? The American College of Surgeons National Surgical Quality Improvement Program® (ACS-NSQIP) database was queried to identify 14,494 patients who had undergone TSA between 2005 and 2016, excluding patients who had undergone hemiarthroplasties of the shoulder and revision shoulder arthroplasties. The ACS-NSQIP database was utilized in this study for the comprehensive preoperative and postoperative medical histories it provides for each patient for 274 characteristics. Among the 14,494 patients undergoing TSA, 931 (6%) patients who had a history of COPD were identified, and the two cohorts-COPD and non-COPD-were analyzed for differences in their demographic factors, comorbidities, and acute complications occurring within 30 days of their procedure. Univariate analyses were utilized to assess differences in the prevalence of demographic features, comorbidities, and perioperative/postoperative outcomes after surgery. Multivariate regression analyses were used to assess COPD as an independent risk factor associated with complications. COPD is an independent risk factor for three complications after TSA: pneumonia (odds ratio [OR], 2.793; 95% confidence interval [CI], 1.426-5.471; p = 0.003), bleeding resulting in transfusion (OR, 1.577; 95% CI, 1.155-2.154; p = 0.004), and septic shock (OR, 9.259; 95% CI, 2.140-40.057; p = 0.003). In light of the increased risk of these serious complications, surgeons should have a lower threshold of suspicion for infection in patients with COPD after TSA so that adequate measures can be taken before developing severe infectious complications including pneumonia and septic shock. Surgeons may also consider administering tranexamic acid in patients with COPD undergoing TSA to reduce the amount of blood transfusions necessary. Future work through randomized control trials analyzing (1) the effectiveness of more aggressive infection prophylaxis in decreasing the risk of pneumonia/septic shock; and (2) the use of tranexamic acid in decreasing blood transfusion requirements in patients with COPD undergoing TSA is warranted. Level III, therapeutic study.

Journey of the glenoid in anatomic total shoulder replacement.

Anatomic total shoulder arthroplasty (TSR) has been shown to generate good to excellent results for patients with osteoarthritis and a functioning rotator cuff. Many studies have reported that the glenoid component loosening and failure remain the most common long-term complication of total shoulder arthroplasty. The approach to glenoid component is critical because a surgeon should consider patient-specific anatomy, preserving bone stock and joint line restoration, for a good and durable shoulder function. Over the years, different glenoid design and materials have been tried in various configurations. These include cemented polyethylene, uncemented metal-backed and hybrid implants. Although advances in biomechanics, design and tribology have improved our understanding of the glenoid, the journey of the glenoid component in anatomic total shoulder arthroplasty has not yet reached its final destination. This article attempts to describe the evolution of the glenoid component in anatomic TSR and current practice.

Paper #3 - Hybrid Cage Glenoids Compared to Cemented Peg Glenoids in Anatomic Total Shoulder Arthroplasty

Introduction: Aseptic glenoid loosening remains a long-term complication of total shoulder arthroplasty (TSA). To improve long-term fixation and decrease the risk of aseptic loosening, glenoid components with hybrid fixation, consisting of a large metal ingrowth central peg and cemented peripheral pegs, have been developed. The purpose of this prospective study is to determine the clinical and radiographic outcomes of a hybrid cage glenoid component compared to an age and gender matched polyethylene (PE) peg glenoid component with a minimum tow year follow-up.

Total shoulder arthroplasty: risk factors for intraoperative and postoperative complications in patients with primary arthritis

This study evaluated and identified risk factors for the development of intraoperative and postoperative surgical complications in total shoulder arthroplasty in patients with primary osteoarthritis. We evaluated patient-specific factors, including age, sex, body mass index, prior nonarthroplasty surgery, smoking, alcohol consumption, and the American Society of Anesthesiologists (ASA) Physical Status Classification System in 275 patients (76 men, 199 women) with an average age of 68 years (range, 51-85 years). We categorized the number and severity of all complications and correlated these results with the patient-specific factors RESULTS: Twenty-seven complications (9.8%) in 275 shoulder arthroplasties were recorded. We identified 22 patients (8%) with category I complications and 5 (2.8%) with category II complications. Patients with an ASA score of 3 showed an increased likelihood of having a surgical complication compared with the control group with ASA scores of 1 and 2 (odds ratio, 4.28; 95% confidence interval, 1.79-10.20; P < .01). Smokers were more prone to surgical complications than nonsmokers (odds ratio, 5.08; 95% confidence interval, 1.96-13.11; P = .02). Surgical complication rates after anatomic total shoulder arthroplasty in patients with primary osteoarthritis correlate with the patient's overall health status and nicotine consumption. This may be useful for predicting the likelihood of surgical complications and may thus prove important for clinicians to better assess and explain possible risks before surgery.

Paper #3 - Comparison of cemented polyethylene peg and hybrid cage glenoids in total shoulder arthroplasty

Introduction: Aseptic glenoid loosening remains a long-term complication of total shoulder arthroplasty (TSA). To improve long-term fixation and decrease the risk of aseptic loosening, glenoid components with hybrid fixation, consisting of a large metal ingrowth central peg and cemented peripheral pegs, have been developed. The purpose of this prospective study is to determine the clinical and radiographic outcomes of a hybrid cage glenoid component compared to an age and gender matched polyethylene (PE) peg glenoid component with a minimum tow year follow-up. Methods: Ninety-two patients with a mean age of 63 years were treated with a TSA for osteoarthritis by 7 surgeons using either a cemented pegged glenoid or a hybrid fixation cage glenoid. Forty-six patients who received a cage glenoid (19 female and 27 males) were matched for sex and age with 46 patients who received a peg glenoid, and all had a minimum 2 year follow-up. The patients were scored preoperatively and at latest follow-up using the SST, UCLA, ASES, Constant, and SPADI metrics; active abduction, forward flexion, and active and passive external rotation were also measured. The average follow-up for all patients was 26 months (cage 25 months; peg 26 months). A Student's two-tailed, unpaired t-test was used to identify differences in preoperative, postoperative, and pre-to-post-operative improvements in results, where P < .05 denoted a significant difference. IRB approval was obtained at each institution. Results: All patients demonstrated significant improvements in pain and function following TSA with a cage or peg glenoid (P < .0001). For the cage prosthesis, ASES scores improved from 37 to 89, Constant scores from 39 to 76 (P < .0001). Significant improvements were also seen in the SST, UCLA and SPADI scores (P < .001). For the peg glenoid, ASES scores improved from 35 to 84, Constant scores from 39 to 69 (P < .0001), and significant improvements were also seen in the SST, UCLA and SPADI scores (P < .0001). Active forward flexion for a cage glenoid improved from 104° to 149° and active external rotation from 22° to 49°. Active forward flexion for a peg prosthesis improved from 92° to 135° and active external rotation from 16° to 47° (all P < .0001). Cemented peg glenoids were noted to have significantly lower preoperative abduction measurements; however, no significant differences were observed in any postoperative clinical metric or motion measurement except for the SPADI score (P = .0497) and active forward flexion (P = .0427). Cage prostheses were associated with significantly less blood loss than a peg glenoid (mean blood loss, 242 cc vs 337 cc; P = .022). Radiolucent lines were noted in 14% of cage glenoid patients and 28% of peg patients. There were no cases of radiographic or clinical loosening, clinical failures or revisions in either cohort. There were 3 complications in the cage glenoid group and 4 complications in the peg patients. Discussion: Similar clinical outcomes were found at a minimum two years follow-up comparing a standard cemented peg glenoid with a hybrid cage glenoid prosthesis. The 50% reduction in radiolucent lines for the cage relative to the cemented peg glenoid is significant. This is a proof of concept study demonstrating statistically significant clinical improvements and a significant decrease in the incidence of radiolucent lines following implantation of a hybrid cage glenoid component. Additional and longer-term follow-up is needed to confirm these early outcomes.

Metal-Backed Glenoid Components Have a Higher Rate of Failure and Fail by Different Modes in Comparison with All-Polyethylene Components: A Systematic Review.

Glenoid component failure is a common and serious complication of total shoulder arthroplasty. The purpose of this study was to evaluate published evidence on whether metal backing lessens the rate of glenoid component failure. A comprehensive systematic review yielded twenty-one studies on radiolucency, radiographic failure, and revision after arthroplasty with metal-backed glenoid components and twenty-three studies with all-polyethylene components. Our analysis included data on 1571 metal-backed and 3035 all-polyethylene components. The mean duration of follow-up was 5.8 years in the studies with metal-backed components and 7.3 years with all-polyethylene components. All-polyethylene components had a 42.5% rate of radiolucency compared with 34.9% for metal-backed components (p = 0.0026) and a 21.1% rate of radiographic loosening or failure compared with 16.8% for metal-backed components (p = 0.0005). However, the rate of revision was more than three times higher with metal-backed components (14.0%) than with all-polyethylene components (3.8%, p < 0.0001). Although 77% of the revisions of all-polyethylene components were for loosening, 62% of the revisions of metal-backed components were for other reasons, such as component fracture, screw breakage, component dissociation, polyethylene wear, metal wear, and rotator cuff tear (p < 0.0001). The published evidence indicates that metal-backed glenoid components require revision at a significantly higher rate and for different reasons in comparison with all-polyethylene components. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Intraoperative nerve monitoring during total shoulder arthroplasty surgery.

Nerve injury is an acknowledged complication of total shoulder arthroplasty (TSA). Although the incidence of postoperative neurological deficit has been reported to be between 1% and 16%, the true incidence of nerve damage is considered to be higher. The present study aimed to identify the rate of intraoperative nerve injury during total shoulder arthroplasty and to determine potential risk factors. A prospective study of nerve conduction in 21 patients who underwent primary or revision TSA was carried out over a 12-month period. Nerve conduction was monitored by measuring intraoperative sensory evoked potentials (SEP). A significant neurophysiological signal change was defined as either a unilateral or bilateral decrease in SEP signal of ≥50%, a latency increase of ≥10% or a change in waveform morphology, not caused by operative or anaesthetic technique. Seven (33%) patients had a SEP signal change. The only significant risk factor identified for signal change was male sex (odds ratio 15.00, 95% confidence interval). The median nerve was the most affected nerve in the operated arm. All but one signal change returned to normal before completion of the operation and no patient had a persisting postoperative clinical neurological deficit. The incidence of intraoperative nerve damage may be more common than previously reported. However, the loss of SEP signal is reversible and does not correlate with persisting clinical neurological deficits. The median nerve appears to be most at risk. Monitoring SEPs in the operated limb during TSA may be a valuable tool during TSA.

Predictors of Early Complications of Total Shoulder Arthroplasty

The authors hypothesized that age, body mass index (BMI), and medical comorbidities (graded with the Charleson Comorbidiy index [CCI]) could be used to predict early complications after TSA. The authors performed a retrospective review of primary TSAs with a minimum of 90-day follow-up. One hundred twenty-seven patients met the inclusion criteria. Complications occurred in 12 (9.4%) of patients. Major complications occurred in 1 patient (0.8%), medical in 8 (6.3%), and surgical in 4 (3.1%). CCI significantly correlated with complication rates and multivariate regression analysis demonstrated CCI to be the only significant determinant of overall complication rates (P = 0.005) and medical complication rates (P = 0.015). While BMI subgroup did not affect complication rates, transfusion rates, intra-operative blood loss, or operative time, our study may have been underpowered for this variable.