Risk factors for periprosthetic infection after reverse shoulder arthroplasty

Modified frailty index is an effective risk-stratification tool for patients undergoing total shoulder arthroplasty

BACKGROUND

Frailty, as quantified by the modified frailty index (mFI), has emerged as a promising method to identify patients at high risk of complications after surgery. Several studies have shown that frailty, as opposed to age, is more predictive of adverse surgical outcomes. We hypothesized that a 5-item mFI could be used to identify patients at elevated risk of complications after total shoulder arthroplasty (TSA).

METHODS

We identified patients aged 50 years or older who underwent TSA in the American College of Surgeons National Surgical Quality Improvement Program database. Pearson χ² analysis and linear regression were used to determine the association of the mFI score with 30-day postoperative complications, reoperation, readmission, length of stay (LOS), adverse hospital discharge, and mortality rate.

RESULTS

The study included 9861 patients with a mean age of 70 years. As the mFI score increased from 0 to 2 or greater, the following rates increased: postoperative complications from 4.2% to 9.4%, readmission from 1.6% to 4.4%, adverse hospital discharge from 6.3% to 19.6%, and LOS from 1.88 days to 2.43 days (P < .001). Multivariate analysis showed that patients with an mFI score of 2 or greater were over twice as likely to sustain a postoperative complication (odds ratio [OR], 2.4; 95% confidence interval [CI], 1.86-3.10), readmission (OR, 2.80; 95% CI, 1.88-4.17), reoperation (OR, 1.82; 95% CI, 1.02-3.25), and adverse hospital discharge (OR, 3.14; 95% CI, 2.51-3.92). These effects were all significantly higher compared with age.

CONCLUSION

Frailty is associated with increased rates of 30-day postoperative complications, readmission, reoperation, adverse hospital discharge, and hospital LOS after TSA. Use of a simple frailty evaluation may help inform decision making and risk assessment when considering TSA.

Reducing Lateral Femoral Cutaneous Nerve Palsy in Obese Patients in the Beach Chair Position: Effect of a Standardized Positioning and Padding Protocol

INTRODUCTION

To report on the effectiveness of a standardized patient positioning and padding protocol in reducing lateral femoral cutaneous nerve (LFCN) palsy in obese patients who have undergone shoulder surgery in the beach chair position.

METHODS

We retrospectively reviewed the medical records of 400 consecutive patients with a body mass index (BMI) of ≥30 kg/m who underwent either open or arthroscopic shoulder surgery in the beach chair position by a single surgeon. Before June 2013, all patients were placed in standard beach chair positioning with no extra padding. After June 2013, patients had foam padding placed over their thighs underneath a wide safety strap and underneath the abdominal pannus. Flexion at the waist was minimized, and reverse Trendelenburg was used to position the shoulder appropriately. Patient demographic and surgical data, including age, sex, weight, BMI, presence of diabetes, procedure duration, American Society of Anesthesiologists (ASA) grade, and anesthesia type (general, regional, regional/general) were recorded. Symptoms of LFCN palsy were specifically elicited postoperatively in a prospective fashion and identified clinically by focal pain, numbness, and/or tingling over the anterolateral thigh.

RESULTS

The median age was 58.0 years, and the study consisted of 142 male (36%) and 258 female (64%) subjects. Five cases (3.6%) of LFCN palsy occurred with conventional beach chair positioning, and a single case (0.4%) occurred with the standardized positioning and padding technique (P = 0.02). Median age, sex, presence of diabetes, median BMI, surgery type, and surgical time were not significantly different between the patients who did and did not develop LFCN palsy. All cases resolved completely within 6 months.

DISCUSSION

The occurrence of LFCN palsy following shoulder surgery in the beach chair position remains uncommon, even among obese patients. Use of a standardized positioning and padding protocol for obese patients in the beach chair position reduced the prevalence of LFCN palsy.

LEVEL OF EVIDENCE

Level III (prognostic).

Reverse shoulder arthroplasty has a higher risk of revision due to infection than anatomical shoulder arthroplasty

Aims

The aim of this study was to use national registry database information to estimate cumulative rates and relative risk of revision due to infection after reverse shoulder arthroplasty.

Patients and Methods

We included 17 730 primary shoulder arthroplasties recorded between 2004 and 2013 in The Nordic Arthroplasty Register Association (NARA) data set. With the Kaplan–Meier method, we illustrated the ten-year cumulative rates of revision due to infection and with the Cox regression model, we reported the hazard ratios as a measure of the relative risk of revision due to infection.

Results

In all, 188 revisions were reported due to infection during a mean follow-up of three years and nine months. The ten-year cumulative rate of revision due to infection was 1.4% overall, but 3.1% for reverse shoulder arthroplasties and 8.0% for reverse shoulder arthroplasties in men. Reverse shoulder arthroplasties were associated with an increased risk of revision due to infection also when adjusted for sex, age, primary diagnosis, and year of surgery (relative risk 2.41 (95% confidence interval 1.26 to 5.59); p = 0.001).

Conclusion

The overall incidence of revision due to infection was low. The increased risk in reverse shoulder arthroplasty must be borne in mind, especially when offering it to men. Cite this article: Bone Joint J 2019;101-B:702–707.

Proceedings from the 2018 International Consensus Meeting on Orthopedic Infections: evaluation of periprosthetic shoulder infection

The Second International Consensus Meeting on Orthopedic Infections was held in Philadelphia, Pennsylvania, in July 2018. More than 800 experts from all 9 subspecialties of orthopedic surgery and allied fields of infectious disease, microbiology, and epidemiology were assembled to form the International Consensus Group. The shoulder workgroup reached consensus on 27 questions related to culture techniques, inflammatory markers, and diagnostic criteria used to evaluate patients for periprosthetic shoulder infection. This document contains the group's recommendations and rationale for each question related to evaluating periprosthetic shoulder infection.

Proceedings from the 2018 International Consensus Meeting on Orthopedic Infections: prevention of periprosthetic shoulder infection

The Second International Consensus Meeting on Orthopedic Infections was held in Philadelphia, Pennsylvania, in July 2018. Over 800 international experts from all 9 subspecialties of orthopedic surgery and allied fields of infectious disease, microbiology, and epidemiology were assembled to form a consensus workgroup. The following proceedings on the prevention of periprosthetic shoulder infection come from 16 questions evaluated by delegates from the shoulder section.

Scoping review: Diagnosis and management of periprosthetic joint infection in shoulder arthroplasty

BACKGROUND

The aim of this scoping review is to assess the current evidence regarding periprosthetic shoulder infection to inform development of evidence and consensus-based guidelines.

METHODS

A search of Medline, Embase and PubMed was performed; two authors screened the results independently for inclusion.

RESULTS

Totally 88 studies were included. Incidence of periprosthetic shoulder infection ranged from 0.7% to 7%. The most common organisms to cause periprosthetic shoulder infection were Propionibacterium acnes, Staphylococcus aureus, Staphylococcus epidermidis and coagulase-negative Staphylococcus. Male gender and younger age are the most reported risk factors. Erythrocyte sedimentation rate, C-reactive protein and serum/synovial biomarkers had limited diagnostic accuracy. Thirty-nine studies reported the outcome of surgical management of periprosthetic shoulder infection. Eradication rates vary from 54% to 100% for debridement procedures; 66-100% for permanent spacers; 50-100% following single-stage revision; 60-100% following two-stage revision; and 66-100% following resection arthroplasty.

CONCLUSION

There is wide heterogeneity in study designs and outcomes of studies are often contradictory and due to issues with methodology and small sample sizes the optimal pathways for diagnosis and management cannot be determined from this review. Future research should be based on larger cohorts and randomised trials where feasible to provide more valid research for guiding future treatment of periprosthetic shoulder infection.

Proceedings from the 2018 International Consensus Meeting on Orthopedic Infections: management of periprosthetic shoulder infection

The Second International Consensus Meeting on Orthopedic Infections was held in Philadelphia, Pennsylvania, in July 2018. A multidisciplinary team of international experts from all 9 subspecialties of orthopedic surgery and allied fields of infectious disease, microbiology, and epidemiology was assembled to form the International Consensus Group. The following consensus proceedings from the International Consensus Meeting involve 30 questions pertaining to the management of periprosthetic shoulder infection.

Diabetes Disease Severity Was Not Associated with Risk of Deep Infection or Revision After Shoulder Arthroplasty

BACKGROUND

Prior studies have identified diabetes and disease severity (defined using hemoglobin A1c [HbA1c]) as potential risk factors for complications after shoulder arthroplasty. Evaluations of diabetes status and risk of adverse outcomes beyond the 30-day window either are limited or have not accounted for disease severity. Further, measures of diabetes severity other than HbA1c have yet to be investigated in a shoulder arthroplasty population.

QUESTIONS/PURPOSES

(1) Are diabetes status and glycemic control associated with adverse events, including deep infection, all-cause revision, and 90-day readmission after shoulder arthroplasty? (2) Is postoperative HbA1c associated with revision risk? (3) Is there a threshold of preoperative HbA1c that best identifies patients with diabetes who are at higher risk of 3-year deep infection, 1-year all-cause revision, or 90-day readmission? (4) Can the Adapted Diabetes Complications Severity index (aDCSI) be used as an alternative measure of diabetes severity in evaluating the risk of deep infection, all-cause revision, and 90-day readmission and identification of patients with diabetes at higher risk for these events? (5) Is there a difference between elective and traumatic shoulder arthroplasty patients?

METHODS

We conducted a retrospective registry-based cohort study using Kaiser Permanente's Shoulder Arthroplasty Registry (2005-2015). Primary shoulder arthroplasties were classified as patients with and without diabetes. Patients with diabetes were further evaluated using two disease severity measures (1) HbA1c, with good glycemic control classified as preoperative HbA1c < 7.0% and poor control defined as HbA1c ≥ 7.0%; and (2) aDCSI, classified as mild (score of 0-2) or severe (score ≥ 3) diabetes. Cox regression was used to evaluate the risk of deep infection and revision according to diabetes status and disease severity; conditional logistic regression was used for 90-day readmission. Time-dependent 1-year postoperative HbA1c was used to evaluate revision risk in Cox regression. All models were adjusted for covariates and stratified by elective versus trauma shoulder arthroplasty. Receiver operating characteristic curves were generated for HbA1c and aDCSI to determine whether a threshold exists to identify patients at higher risk of deep infection, all-cause revision, or 90-day readmission. The study sample consisted of 8819 patients; 7353 underwent elective shoulder arthroplasty and 1466 underwent shoulder arthroplasty due to trauma. For elective shoulder arthroplasty, 1430 patients (19%) had diabetes, and among the patients who underwent arthroplasty due to trauma, 444 (30%) had diabetes.

RESULTS

Patients with diabetes who underwent elective shoulder arthroplasty and had poor glycemic control had a higher likelihood of 90-day readmission compared with patients without diabetes (OR, 1.5; 95% CI, 1.0-2.1; p = 0.032). No association was found for patients with diabetes who underwent shoulder arthroplasty due to trauma. No association was found between postoperative HbA1c and revision risk. Receiver operating characteristic curve analysis suggested preoperative HbA1c performed poorly at differentiating adverse events. When using aDCSI, patients with severe diabetes who underwent both elective and traumatic shoulder arthroplasty had a higher likelihood of 90-day readmission compared with patients without diabetes (OR, 1.6; 95% CI, 1.2-2.2; p = 0.001 and OR, 1.8; 95% CI, 1.2-2.7; p = 0.005, respectively). Similar to HbA1c, the aDCSI was a poor classifier in differentiating adverse events.

CONCLUSIONS

Of the longer-term outcomes evaluated, more-severe diabetes was only found to be associated with an increase in 90-day readmissions after shoulder arthroplasty; a stronger association was found when using the aDCSI in identifying diabetes severity. Arbitrary cutoffs in HbA1c may not be the best method for determining risk of postoperative outcomes. Future work investigating perioperative diabetes management should work to identify and validate measures, such as the aDCSI, that better identify patients at higher risk for postoperative outcomes and, more importantly, whether outcomes can be improved by modifying these measures with targeted interventions.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Clinical Characteristics and Long-term Outcomes After Septic Arthritis of the Native Glenohumeral Joint: A 20-Year Retrospective Review

Septic arthritis of the native glenohumeral joint is rare, and there is little information available regarding the natural progression and long-term joint outcomes of this pathology. The authors performed a retrospective analysis of 97 patients with culture-positive glenohumeral septic arthritis between 1995 and 2015 at their institution with a mean clinical follow-up of 83.1 months. Patient records were reviewed to document demographic and laboratory data, clinical presentation, postoperative complications, recurrences, and subsequent shoulder arthroplasty. Common comorbidities uncovered included 20 immunocompromised patients (20.6%), intravenous drug use among 27 patients (27.8%), diabetes mellitus among 40 patients (41.2%), and 18 patients (18.5%) receiving hemodialysis. Staphylococcus aureus was the most common pathogen identified (61 patients; 62.8%), followed by streptococcal species (17 patients; 17.2%). Hematogenous spread of infection was the most common etiology of shoulder sepsis (40.2%). Seven patients (7.2%) developed shoulder sepsis of undetermined etiology in the absence of established risk factors, and 16 patients (16.4%) developed recurrent glenohumeral septic arthritis at a mean of 40 months following initial eradication of infection. Three patients (3.0%) eventually underwent same-side shoulder arthroplasty at a mean of 18 months following septic arthritis, with none experiencing a periprosthetic joint infection. Glenohumeral septic arthritis is highly unlikely in the absence of medical risk factors. Long-term recurrence after clinically successful treatment is low (16.5%), and few patients undergo elective arthroplasty following shoulder septic arthritis. However, orthopedic surgeons can expect 30% to 40% of patients to require multiple trips to the operating room to successfully treat the initial joint infection, regardless of treatment method. [Orthopedics. 2019; 42(1):e118-e123.].

Risk and risk factors for revision after primary reverse shoulder arthroplasty for cuff tear arthropathy and osteoarthritis: a Nordic Arthroplasty Register Association study

BACKGROUND

Reverse shoulder arthroplasty (RSA) has gained increasing popularity in the treatment of rotator cuff tear arthropathy (CTA). The purpose of this study was to evaluate the survival of RSA and the risk factors for revision following RSA.

METHODS

RSA patients with CTA or osteoarthritis were identified from the Nordic Arthroplasty Register Association registry data (2004-2013). Kaplan-Meier survival analysis was used to calculate survival probabilities. Cox multiple regression analysis was used to calculate revision rates adjusted for sex, arthroplasty brand, age (<70 years), and year of surgery.

RESULTS

The study included 1904 patients with RSA (1904 RSAs) (69% women; mean age, 74 years; age range, 35-97 years). Revision was performed in 95 patients (5%), with a 10-year cumulative revision rate of 0.91. The most common reason for revision was infection (n = 42), followed by loosening (n = 16) and instability (n = 12). Most revisions occurred less than 6 months after the primary operation. Men had a significantly increased risk of revision compared with women (risk ratio, 3.8; 95% confidence interval, 2.4-6.1). The most common implants were the Delta Xtend (n = 1366) and Delta Mark III (n = 246). The risk of revision of the Delta Mark III was 2.1 (95% confidence interval, 1.1-4.3) compared with the Delta Xtend. Age and year of surgery were not statistically significantly associated with risk of revision.

CONCLUSION

The overall midterm risk of revision after RSA for CTA was low (5%). The most common reason for early revision was infection. Male sex was associated with a significantly increased risk of revision.

Lack of level I evidence on how to prevent infection after elective shoulder surgery

PURPOSE

Infection is a concern after all orthopedic procedures, including shoulder surgery. This systematic review of literature aimed to determine risk factors for infection as well as the availability and effectiveness of measures utilized to prevent infection after elective shoulder surgery.

METHODS

An electronic database search was performed using MEDLINE (1950-October 2017), EMBASE (1980-October 2017), CINAHL (1982-October 2017), and the Cochrane database to identify studies reporting a risk factor or preventive measure for infection after shoulder surgery.

RESULTS

Fifty-one studies were eligible for inclusion. Risk factors identified for infection were male sex, the presence of hair, receiving an intra-articular cortisone injection within the 3 months prior to surgery, smoking, obesity, and several comorbidities. The only preventive measure with level I evidence was for the use of chlorhexidine wipes for cleansing the skin in the days prior to surgery and for the use of ChloraPrep or DuraPrep over povodine and iodine to prep the skin at the time of surgery. Level II-IV evidence was found for other infection prevention methods such as intravenous antibiotic prophylaxis.

CONCLUSION

There are many risk factors associated with developing an infection after elective shoulder surgery. Many preventive measures have been described which may decrease the risk of infection; however, most lack a high level evidence to support them. The findings of this systematic review are clinically relevant as it has been shown that infection after shoulder surgery results in poor patient-reported outcomes and pose a significant financial burden. As surgeons the goal should be to prevent infections to avoid the morbidity for patients and the increased cost for society.

LEVEL OF EVIDENCE

IV systematic review of literature.

Association of Perioperative Glycemic Control With Deep Postoperative Infection After Shoulder Arthroplasty in Patients With Diabetes

BACKGROUND

Although diabetes mellitus (DM) has been established as a risk factor for infection after lower extremity arthroplasty, no association has been reported with shoulder arthroplasty.

METHODS

We queried a national database for patients with DM who underwent primary shoulder arthroplasty. We identified perioperative hemoglobin A1c (HbA1c) levels and assessed the incidence of wound complications within 6 months and deep infection that required surgical intervention within 1 year for each HbA1c level. We performed a receiver operating characteristic analysis to determine a threshold value of HbA1c.

RESULTS

Patients with DM had markedly higher rates of wound complications (1.4% versus 0.9%; odds ratio, 1.22; P = 0.028) and deep infection (0.7% versus 0.4%; odds ratio, 1.47; P = 0.001). The rates of wound complications (P = 0.0008) and deep postoperative infection (P = 0.002) increased markedly as the perioperative HbA1c level increased. Receiver operating characteristic analysis demonstrated an inflection point at an HbA1c level of 8.0 mg/dL (P = 0.017; sensitivity, 50%; specificity, 75%).

CONCLUSIONS

The risk of wound complications and deep postoperative infection in patients with DM increases as the perioperative HbA1c level increases. An HbA1c level >8.0 mg/dL could serve as a threshold for a markedly increased risk of infection.

LEVEL OF EVIDENCE

Therapeutic level III, case-control study, treatment study.

The role age plays in the outcomes and complications of shoulder arthroplasty

BACKGROUND

This investigation used age as a continuous variable to estimate implant survival and the risk of complications.

METHODS

Prospectively collected data were used to analyze 5494 consecutive shoulder arthroplasties performed from 1970 to 2012. Patients were a mean age of 67 years. The association between the age at the index procedure and the risk for each outcome was assessed using Cox regression and smoothing spline analysis.

RESULTS

Older age was associated with a decreased risk of revision surgery, revision for mechanical failure, and reoperation but with a higher risk for thromboembolic events. Reoperation rates also decreased in a linear fashion with older ages (P < .001). The risk of revision surgery decreased in a linear fashion between the ages of 40 and 85, with a 3% decreased risk of revision per 1-year increase in age (P < .01). This association held true in a multivariate model and when specific procedures were separated out. Compared with patients aged <50 years, patients aged from 50 to 65 years (P < .001) and those >65 years (P < .001) have decreased risks of revision surgery. The risk of a revision surgery in a patient aged >50 years was significantly decreased (~13% reduction in risk for each year; P < .001). There was a subtle association between older age and decreased rates of infection (P = .01).

CONCLUSIONS

There is a strong association between older age and decreased rates of revision surgery and reoperation after shoulder arthroplasty, with a striking association with decreased rates of mechanical failure. These are important considerations when counseling younger patients regarding their risks.

Shoulder arthroplasty following gastric bypass, do complications follow?

INTRODUCTION

Previous reports have shown an increased risk of complications after arthroplasty in the obese population. It remains unclear if gastric bypass surgery prior to shoulder arthroplasty modifies the complication and failure rate. The purpose of this study is to assess the complication and re-operation rates following shoulder arthroplasty in this population.

METHODS

Between 2002 and 2012, 39 shoulders with prior gastric bypass underwent shoulder arthroplasty (3 HA, 16 TSA, 20 RSA). The mean time from the gastric bypass to arthroplasty was 13 years (range, 0.7-32). Shoulders were followed for a minimum of two years (mean, 3.8 years) or until re-operation. Outcome measures included pain, range of motion, satisfaction, modified Neer ratings, and ASES scores.

RESULTS

Complications occurred in seven shoulders (18%), with five requiring re-operation. There was no common failure mechanism. Re-operations occurred for aseptic glenoid loosening, periprosthetic fracture, and unexplained pain. Those shoulders with complications were similar to those without in regard to age, sex, and BMI. Complications were more common following anatomic arthroplasty compared to reverse arthroplasty (5 vs 1, p = 0.06); however, complications were not improved compared to historical controls with morbid obesity. Overall, pain improved significantly from 4.8 pre-operatively to 2.3 postoperatively (p < 0.001). All groups, regardless of arthroplasty type, demonstrated significant improvements in forward elevation and external rotation.

CONCLUSION

Gastric bypass surgery prior to shoulder arthroplasty leads to clinical improvement in both pain and range of motion. Prior gastric bypass surgery does not result in a lower surgical complication rate compared to previously published reports in the morbidly obese population.

LEVEL OF EVIDENCE

Level 4, case series.

Reverse Shoulder Arthroplasty in Patients with Rheumatoid Arthritis: A Systematic Review

Background

There are limited data available regarding the results of reverse shoulder arthroplasty (RSA) in patients with rheumatoid arthritis (RA). We performed a systematic review of the literature to investigate the radiological and clinical outcomes after RSA in patients with RA.

Methods

A literature search for publications between 1987 and 2014 was conducted by 2 independent reviewers using PubMed, Scopus, Embase, and Cochrane Central Register of Controlled Trials. Articles were retrieved by an electronic search using keywords and their combinations. Studies that met inclusion criteria were assessed for pertinent data.

Results

Seven studies including 123 shoulders met the inclusion criteria. The mean age of the patients was 67.9 years and the mean follow-up period was 46.6 months. The mean Constant score and American Shoulder and Elbow Surgeons (ASES) score increased from 18.6 and 27.5 preoperatively to 58.6 and 73.7, respectively, at the final follow-up evaluation. The mean active forward flexion, abduction, and external rotation increased from 57.2°, 50.4°, and 11.4° to 127.1°, 116.7°, and 26.4°, respectively. The incidence of scapular notching was 33.7%. Twenty-seven (22.0%) of 123 shoulders had one or more complications, 12 of which (44.4%) had intraoperative or postoperative fractures. Nine shoulders (7.3%) had one or more revision surgeries.

Conclusions

RSA in RA showed similar short- to mid-term results without higher complication rates as compared to RSA in cuff tear arthropathy. Although RSA can be considered a reliable treatment option in patients with RA, further large-scale studies are required to determine the long-term survival of the implant.

Surgical management of periprosthetic shoulder infections

BACKGROUND

The treatment of periprosthetic joint infection is a difficult challenge in shoulder arthroplasty. This study investigated 1-stage modular component exchange vs. 1-stage complete removal and reimplantation (CRR) vs. 2-stage revision arthroplasty for periprosthetic joint infection.

METHODS

Between January 1, 2004, and December 31, 2012, 79 patients received a component exchange (n = 15), CRR (n = 45), or a 2-stage (n = 19) revision for infection. A binary logistic regression analysis was performed to determine factors presenting the greatest risk of reinfection. Complications and functional outcomes were also evaluated.

RESULTS

Overall, 4 of 15 (27%) component exchanges, 2 of 45 (4%) CRRs, and 4 of 19 (21%) 2-stage procedures required a reoperation for infection with a minimum of 1 year of follow-up. The difference between the CRR group and exchange group was significant (P = .030); however, the difference between the CRR group and 2-stage group did not reach statistical significance (P = .059). No preoperative and intraoperative selection bias between the groups was found. Binary logistic regression predicted that reinfection was highest in patients whose cultures grew Staphylococcus aureus (P = .004) or coagulase-negative Staphylococcus species (P = .041) or those treated with a component exchange (P = .015). The difference between groups for noninfection-related complications was not significant (P = .703). All procedures provided improved functional outcomes and pain relief.

CONCLUSION

Patients with infection caused by Staphylococcus aureus or coagulase-negative Staphylococcus species may require additional operations to treat the infection. Although effective in some cases, component exchange presents an increased risk for reinfection. A 1-stage CRR procedure had similar reinfection rates as a 2-stage procedure in our patient population.

Increasing Body Mass Index Is Associated with Worse Outcomes After Shoulder Arthroplasty

BACKGROUND

Although obesity is associated with increased complication rates after lower-extremity arthroplasty, there is a relative paucity of studies examining the effect of body mass index (BMI) on shoulder arthroplasty. The purpose of this investigation was to evaluate the effect of BMI on implant survival and the rate of complications after shoulder arthroplasty.

METHODS

Using an institutional total joint registry, 4,567 consecutive shoulder arthroplasty cases from 1970 to 2013 were studied. The mean BMI was 29.7 kg/m (range, 14 to 66 kg/m), with 1,622 patients (36%) with a BMI of 30 to 40 kg/m and 297 patients (7%) with a BMI of >40 kg/m. There were 2,493 female patients (55%). BMI was dichotomized after examination of the smoothing spline curve. The associations of factors and complications were assessed using Cox proportional hazard regression analysis.

RESULTS

Increasing BMI was associated with an increased risk of a revision surgical procedure, reoperation, revision for mechanical failure, and superficial infection, and it was negatively associated with risk of a periprosthetic fracture. The risk of a revision surgical procedure increased in a linear fashion with increasing BMI (hazard ratio [HR], 1.05, or a 5% increased risk per 1 unit of BMI; p = 0.03). Increased BMI was also associated with an increased risk of revision for mechanical failure (HR, 1.05; p = 0.004). In a multivariate model, the association of BMI and risk of a revision for any reason, revision for mechanical failure, and reoperation maintained significance (p ≤ 0.02). The most marked association between increasing BMI and any complication in shoulder arthroplasty was its association with superficial wound infection (HR, 1.09; p = 0.03).

CONCLUSIONS

Increasing BMI is strongly associated with increased rates of revision surgical procedures and postoperative complications after shoulder arthroplasty. It is important to consider these findings when counseling patients, estimating risks, and estimating complication risks in policy decisions.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Long-term outcomes of cemented versus cementless humeral components in arthroplasty of the shoulder

Aims

In the initial development of total shoulder arthroplasty (TSA), the humeral component was usually fixed with cement. Cementless components were subsequently introduced. The aim of this study was to compare the long-term outcome of cemented and cementless humeral components in arthroplasty of the shoulder.

Patients and Methods

All patients who underwent primary arthroplasty of the shoulder at our institution between 1970 and 2012 were included in the study. There were 4636 patients with 1167 cemented humeral components and 3469 cementless components. Patients with the two types of fixation were matched for nine different covariates using a propensity score analysis. A total of 551 well-balanced pairs of patients with cemented and cementless components were available after matching for comparison of the outcomes. The clinical outcomes which were analysed included loosening of the humeral component determined at revision surgery, periprosthetic fractures, post-operative infection and operating time.

Results

The overall five-, ten-, 15- and 20-year rates of survival were 98.9%, 97.2%, 95.5%, and 94.4%, respectively. Survival without loosening at 20 years was 98% for cemented components and 92.4% for cementless components. After propensity score matching including fixation as determined by the design of the component, humeral loosening was also found to be significantly higher in the cementless group. Survival without humeral loosening at 20 years was 98.7% for cemented components and 91.0% for cementless components. There was no significant difference in the risk of intra- or post-operative fracture. The rate of survival without deep infection and the mean operating time were significantly higher in the cemented group.

Conclusion

Both types of fixation give rates of long-term survival of > 90%. Cemented components have better rates of survival without loosening but this should be weighed against increased operating time and the risk of bony destruction of the proximal humerus at the time of revision of a cemented humeral component. Cite this article: Bone Joint J 2017;99-B:666–73.

Periprosthetic shoulder infection: an overview

Periprosthetic shoulder infection (PSI) is rare but potentially devastating. The rate of PSI is increased in cases of revision procedures, reverse shoulder implants and co-morbidities. One specific type of PSI is the occurrence of low-grade infections caused by non-suppurative bacteria such as Propionibacterium acnes or Staphylococcus epidemermidis.

Success of treatment depends on micro-organism identification, appropriate surgical procedures and antibiotic administration efficiency. Post-operative early PSI can be treated with simple debridement, while chronic PSI requires a one- or two-stage revision procedure. Indication for one-time exchange is based on pre-operative identification of a causative agent. Resection arthroplasty remains an option for low-demand patients or recalcitrant infection.

Cite this article: EFORT Open Rev 2017;2:104-109. DOI: 10.1302/2058-5241.2.160023

Is previous nonarthroplasty surgery a risk factor for periprosthetic infection in primary shoulder arthroplasty?

BACKGROUND

The purpose of this study was to determine the risk of periprosthetic infection after primary shoulder arthroplasty (SA) in patients undergoing previous nonarthroplasty shoulder surgery compared with those without previous surgery.

MATERIALS AND METHODS

All patients undergoing primary SA at our institution between 1970 and 2012 were included in this study. The cohort consisted of 4577 patients treated with 2890 total SAs, 1233 hemiarthroplasties, and 454 reverse SAs; 813 (18%) patients had undergone prior nonarthroplasty shoulder surgery on the operative side. Patients with and without previous surgery were compared for postoperative periprosthetic infection. Univariate and multivariable analyses were used.

RESULTS

Deep postoperative infection of the shoulder was diagnosed in 68 patients (1.49%). Of the 813 patients who had undergone previous surgery, 20 (2.46%) developed a deep postoperative infection. However, of the 3764 patients who did not have previous shoulder surgery, 48 patients (1.28%) sustained deep shoulder infection. This difference was significant in both the univariate (P = .0094) and multivariate analyses (P = .0390). In addition, older age and female gender were significantly associated with a lower risk of deep postoperative infection (P = .0150 and P = .0074, respectively). A higher number of previous surgeries was also significantly associated with an increased risk of deep postoperative infection (P = .0272).

CONCLUSIONS

The risk of infection after primary SA is significantly higher in patients with a history of prior non-arthroplasty-related surgery. This finding should be discussed with the patients before their surgery, and potential preoperative and intraoperative workup should be undertaken to identify at-risk patients.

Complications in reverse shoulder arthroplasty

The reported rate of complications of reverse shoulder arthroplasty (RSA) seems to be higher than the complication rate of anatomical total shoulder arthroplasty.The reported overall complication rate of primary RSA is approximately 15%; when RSA is used in the revision setting, the complication rate may approach 40%.The most common complications of RSA include instability, infection, notching, loosening, nerve injury, acromial and scapular spine fractures, intra-operative fractures and component disengagement.Careful attention to implant design and surgical technique, including implantation of components in the correct version and height, selection of the best glenosphere-humeral bearing match, avoidance of impingement, and adequate management of the soft tissues will hopefully translate in a decreasing number of complications in the future. Cite this article: Barco R, Savvidou OD, Sperling JW, Sanchez-Sotelo J, Cofield RH. Complications in reverse shoulder arthroplasty. EFORT Open Rev 2016;1:72-80. DOI: 10.1302/2058-5241.1.160003.

The influence of diabetes mellitus and obesity on upper limb arthroplasty outcomes: a systematic review protocol

REVIEW QUESTION/OBJECTIVE

The objective of this review is to locate and synthesize the best available evidence investigating the impact of selected comorbidities on upper limb arthroplasty outcomes.The review question is: Are patients with diabetes mellitus or obesity at an increased risk of complications and/or poorer postoperative outcomes following total shoulder, reverse total shoulder and total elbow arthroplasty?

Safety and efficacy of shoulder arthroplasty following lower extremity periprosthetic joint infection

BACKGROUND

The safety of arthroplasty in patients with a previous periprosthetic joint infection (PJI) remains unclear. The objective of this study was to determine whether patients with a history of a properly treated PJI complicating lower extremity arthroplasty can safely undergo shoulder arthroplasty without an increased risk of shoulder infection or compromise in their clinical outcomes.

METHODS

Between 2002 and 2013, 36 patients with successful treatment of an infected lower extremity arthroplasty underwent a subsequent primary shoulder arthroplasty. Three were lost to follow-up. The remaining 33 shoulders were analyzed at a mean follow-up of 3.5 years for radiographic, clinical, and functional outcomes. Nine patients were receiving chronic antibiotic suppression at the time of their index shoulder arthroplasty. The mean time between PJI treatment and shoulder arthroplasty was 4.7 years (range, 0.7-13.1 years).

RESULTS

Shoulder arthroplasty led to improved pain scores and range of motion. Excellent or satisfactory modified Neer ratings were achieved in 78.8% of patients. There was no difference in American Shoulder and Elbow Surgeons scores between the groups with and without chronic antibiotic suppression. There were 2 reoperations, both in patients not receiving chronic suppression. The indications were aseptic glenoid loosening and infection after a periprosthetic fracture. The final estimated survival free of infection was 93.3%.

DISCUSSION/CONCLUSION

Shoulder arthroplasty in patients with a history of PJI complicating hip or knee arthroplasty seems to be safe, with a low rate of infection. Thus, previous lower extremity PJI should not be considered a relative contraindication to shoulder arthroplasty.

Effect of smoking on complications following primary shoulder arthroplasty

BACKGROUND

The purpose of this study was to examine the effect of smoking on the incidence of complications after primary anatomic total shoulder arthroplasty (TSA) and reverse shoulder arthroplasty (RSA).

METHODS

All patients who underwent primary TSA or RSA at our institution between 2002 and 2011 and had a minimum 2-year follow-up were included. Smoking status was assessed at the time of surgery. Current smokers, former smokers, and nonsmokers were compared for periprosthetic infection, fractures (intraoperative and postoperative), and loosening after surgery.

RESULTS

The cohort included 1834 shoulders in 1614 patients (814 in smokers and 1020 in nonsmokers). Complications occurred in 73 patients (75 shoulders; 44 in smokers and 31 in nonsmokers). There were 20 periprosthetic infections (16 in smokers and 4 in nonsmokers), 27 periprosthetic fractures (14 in smokers and 13 in nonsmokers), and 28 loosenings (14 in smokers and 14 in nonsmokers). Smokers had lower periprosthetic infection-free survival rates (95.3%-99.4% at 10 years; P = .001) and overall complication-free survival rates (78.4%-90.2%; P = .012) than nonsmokers. Multivariable analyses showed that both current and former smokers had significantly higher risk of periprosthetic infection in comparison with nonsmokers (hazard ratio [HR], 7.27 and 4.56, respectively). In addition, current smokers showed a higher risk of postoperative fractures than both former smokers (HR, 3.63) and nonsmokers (HR, 6.99).

CONCLUSIONS

This study demonstrates that smoking is a significant risk factor of complications after TSA and RSA. These findings emphasize the need for preoperative collaborative interventions, including smoking cessation programs.

Revision for a failed reverse: a 12-year review of a lateralized implant

BACKGROUND

The purpose of this study was (1) to evaluate the rates of reverse shoulder arthroplasty (RSA) revisions during a 12-year period, (2) to assess the influence of primary diagnosis and the impact of implant modifications on revisions, (3) to describe surgical management of failed RSA, and (4) to analyze outcomes of patients with minimum 24-month follow-up.

METHODS

A retrospective database review identified primary diagnosis for 1418 patients who underwent RSA from 2000 to 2012. A subgroup of 85 patients required return to the operating room for removal or exchange of components. Indication to reoperate, intraoperative management, and outcomes were reviewed. Indications were grouped into 7 categories: baseplate failure, humeral component dissociation, glenosphere dissociation, glenohumeral dislocation, aseptic humeral loosening, periprosthetic fracture, and infection. During the study, design modifications were made to the baseplate, humeral socket, and glenosphere. Surgical strategies were analyzed through operative reports. Range of motion, American Shoulder and Elbow Surgeons scores, and Simple Shoulder Test scores were collected before and after surgery and compared for 58 patients with 2-year follow-up.

RESULTS

Overall revision rate was 6%. Patients undergoing RSA for failed hemiarthroplasty had the highest revision rate (10%). Indications for revision included baseplate failure (2.5%), infection (1.3%), humeral dissociation (0.7%), glenosphere dissociation (0.6%), periprosthetic fracture (0.4%), glenohumeral dislocation (0.4%), and aseptic humeral loosening (0.3%). Baseplate modifications reduced the incidence of baseplate failure to 0.3%. Range of motion and the Simple Shoulder Test and American Shoulder and Elbow Surgeons scores improved.

CONCLUSION

Although revision RSA is challenging, with higher risk for complications compared with primary RSA, patients still exhibit significant clinical improvements.

Complications and revision of reverse total shoulder arthroplasty

The most common causes of revision surgery after reverse total shoulder arthroplasty (RTSA) are, in decreasing order: prosthetic instability (38%), infection (22%), humeral problems (21%) including loosening, unscrewing and fracture, and, lastly, problems of glenoid loosening (13%). Complications leading to reoperation are often multiple and their association is underestimated. It is not uncommon for patients to be reoperated several times due to the persistence of the same complication, failure to diagnose associated complications, or onset of an additional complication. Although it may require a number of procedures in the same patient, it is very often possible (in 90% of cases, in our experience) to conserve or replace the RTSA, allowing patients to recover a functional shoulder. However, the functional results of revised RTSA are inferior than for primary prostheses, and depend on the surgeon's experience and the number of RTSAs performed, suggesting that patients should be referred to a tertiary center.

Superobesity (body mass index >50 kg/m2) and complications after total shoulder arthroplasty: an incremental effect of increasing body mass index

BACKGROUND

The prevalence of obesity in the United States continues to increase. Attention has recently turned to an emerging population of extremely overweight patients, termed superobese and defined as those with body mass index (BMI) ≥50 kg/m(2). The goal of this study was to use a national database to evaluate postoperative complication rates after total shoulder arthroplasty (TSA) in superobese patients and to compare patients of different BMI classes.

METHODS

Patients who underwent TSA or reverse TSA were identified in the PearlDiver database by International Classification of Diseases, Ninth Revision (ICD-9) codes. These patients were then divided into nonobese, obese, morbidly obese, and superobese cohorts by ICD-9 codes. Postoperative complications were assessed and compared between cohorts.

RESULTS

From 2005 to 2012, 144,239 unique patients who underwent TSA or reverse TSA were identified, including 105,661 nonobese patients, 23,864 obese patients, 13,759 morbidly obese patients, and 955 superobese patients. Superobese patients had a significantly higher rate of infection, dislocation, component loosening, revision shoulder arthroplasty, venous thromboembolism, and medical complications after shoulder arthroplasty compared with nonobese controls.

CONCLUSIONS

Obesity is associated with significantly increased rates of numerous complications after TSA, including infection, dislocation, component loosening, revision surgery, venous thromboembolism, and medical complications, compared with nonobese controls. Superobesity (BMI > 50 kg/m(2)) is associated with significantly increased rates of several complications compared with even obese and morbidly obese patients, including infection, component loosening, venous thromboembolism, and medical complications.