Analysis of 4063 complications of shoulder arthroplasty reported to the US Food and Drug Administration from 2012 to 2016

From the last 100 to the first 100-outcome after a manufacturer change in reverse fracture arthroplasty

PURPOSE

If surgery is indicated for elderly patients suffering a proximal humerus fracture, reverse fracture arthroplasty became the preferred type of treatment due to its good and reliable outcomes over the last decade. Surgeons could choose from a wide range of implants and up to now there was no evaluation, if a change of the manufacturer affects patients` outcome.

METHODS

The last 100 patients before and the first 100 after manufacturer change in reverse fracture arthroplasty were evaluated at a level one trauma center, all treated by only 3 senior shoulder surgeons. Clinical as well as radiographic outcome parameters were assessed, perioperative up to 24 months after surgery.

RESULTS

Mean age in both groups was nearly 80 years with comparable distribution of gender and comorbidities. A trend to shorter duration of surgery was observed after the change, mainly according to an uncemented fixation of the stem. During follow-up no significant differences, beneficial as well as negative, could be observed regarding clinical and radiographic outcome.

CONCLUSION

A manufacturer change on the fly is possible without negative consequences for patients` outcome. Expertise of the whole OR-team as well as standardized training with the new implant seems to be a more important factor than a specific type of implant.

An Analysis of the Complication Reports of Expandable Lumbar Interbody Cages in the Food and Drug Administration Manufacturer and User Facility Device Experience Database

BACKGROUND

Expandable lumbar interbody cages (ELICs) are commonly used for interbody fusion and provide lordotic correction by lengthening the anterior column of the vertebral spine. We sought to identify unique failure mechanisms and significant differences in the types of complications associated with ELICs as reported to the Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE) Database.

MATERIALS AND METHODS

The MAUDE Database was analyzed for complication reports submitted for ELIC systems between January 2013 and July 2023. Reports were categorized by manufacturer, brand name, type of expandable cage, type of complication, year of complication, and reporter identity. Reports that were duplicated or had insufficient information were excluded from analysis. The top 5 manufacturers with the most implant-related complications were independently analyzed and compared.

RESULTS

A total of 821 reports were analyzed. The top 5 complications reported across all manufacturers were cage breakage during insertion (25.7%), postoperative migration without collapse (16.0%), postoperative collapse (15.6%), inserter breakage (11.1%), and tubing problems (3.0%). A significant difference was detected in complication type between manufacturers (χ2=557, P<.001). The largest number of reports (120, 14.6%) was in 2016.

CONCLUSION

With FDA approval of novel ELIC systems and the adoption of newer surgical techniques, understanding the range of potential complications is paramount in ensuring patient safety. This study of the MAUDE Database provides a comprehensive summary of adverse reported events associated with ELICs during the past decade. [Orthopedics. 2025;48(1):e7-e14.].

Outcomes after revision surgery for glenoid baseplate failure in reverse shoulder arthroplasty

Background

The purpose of this study was to report clinical outcomes in patients who underwent revision surgery for glenoid baseplate failure after index reverse shoulder arthroplasty (RSA).

Methods

A retrospective review was performed to identify patients from 2010 to 2020 at a single institution who sustained glenoid baseplate failure after RSA and underwent revision surgery. Exclusion criteria included periprosthetic joint infection or lack of minimum 1 year clinical and radiographic follow-up. Included patients were contacted for clinical outcomes (American Shoulder Elbow Surgeons (ASES), Visual Analog Scale (VAS) pain, Single Assessment Numeric Evaluation (SANE) and Patient Satisfaction scores).

Results

A total of 24 patients were identified, and 22 out of 24 (92%) patients were available for clinical follow-up at a mean period of 3.4 years after final revision surgery. The mean age was 70 years, and 15 out of 22 (68%) patients were female. A total of 17 patients were revised to RSA, and five patients were revised to hemiarthroplasty. For the 22 included patients, the mean follow-up ASES score was 64.6, VAS pain was 2.4 and SANE was 58%, which were all significantly improved versus pre-revision. In total, 64% of patients were satisfied or completely satisfied.

Discussion

Revision surgery after glenoid baseplate failure in RSA yields unpredictable clinical outcomes. Revision to RSA or hemiarthroplasty both resulted in modest functional results with persistent mild pain.

Therapeutic arthroscopy for noninfectious stiffness and anterior shoulder pain after reverse shoulder arthroplasty leads to clinical improvement in most patients with a low complication rate

BACKGROUND

Reverse shoulder arthroplasty (RSA) exhibits favorable outcomes in managing rotator cuff arthropathy, primary glenohumeral arthritis, and complex proximal humeral fractures. Despite its success and reliability, certain patients experience persistent pain and stiffness. The clinical utility of therapeutic arthroscopy in RSA patients remains an area for investigation. The purpose of this study was to report clinical outcomes, including patient-reported outcomes (PROs), range of motion (ROM), and satisfaction, in patients who underwent therapeutic arthroscopy for noninfectious stiffness and subcoracoid impingement following RSA. The hypothesis was that patients would experience clinical improvement and satisfaction, with earlier intervention being superior to later intervention.

METHODS

Multicenter retrospective review on patients who underwent therapeutic arthroscopy for noninfectious stiffness and anterior shoulder pain following RSA with minimum 1-year follow-up. PROs and ROM were collected preoperatively and postoperatively. Subjective improvement in ROM and pain, complications, satisfaction, and return to activities were recorded. Data was stratified into 2 cohorts based on timing of RSA to arthroscopy (1 year or less was considered early intervention and >1 year late intervention) and variables were analyzed for each cohort.

RESULTS

A total of 19 patients met the study criteria (13 patients in early intervention cohort, 6 in late intervention cohort). The average time from the index surgery to arthroscopy was 7.7 ± 2.1 months in the early intervention cohort and 28.3 ± 10.3 months in the late intervention cohort (P = .004). The overall cohort improved significantly regarding pain (Visual Analog Scale [VAS]: Δ-1.1, P = .003), ROM (forward flexion [FF]: Δ21°, P = .002; external rotation: Δ14°, P = .010; internal rotation: Δ1 spinal level, P = .023) and PROs (American Shoulder and Elbow Surgeons: Δ18.2, P = .001; Subjective Shoulder Value: Δ16.3, P = .009). The early intervention cohort demonstrated significant improvement in VAS (Δ-1.1, P = .029), American Shoulder and Elbow Surgeons (Δ16.2, P = .013), Subjective Shoulder Value (Δ18.5, P = .008), FF (Δ23°, P = .016), and external rotation (Δ15°, P = .028). The late intervention cohort had significant improvement in VAS (Δ-1.3, P = .048) and FF (Δ17°, P = .017). Seventy-four percent of patients in the overall cohort reported decreased pain, 79% improvement in ROM, 68% returned to activities, and 74% were satisfied. There were no complications.

CONCLUSION

Therapeutic arthroscopy for noninfectious stiffness and anterior shoulder pain following RSA improves clinical outcomes in most patients with a low complication risk. Although postoperative outcomes were comparable between groups, functional improvement was more likely in patients who underwent intervention earlier.

Preoperative corticosteroid injections are associated with a higher periprosthetic infection rate following primary total shoulder arthroplasty: a systematic review and meta-analysis

BACKGROUND

Corticosteroid injections (CSIs) are commonly used for the treatment of shoulder pain in patients with osteoarthritis and rotator cuff arthropathy. These injections may increase the risk of infection following eventual shoulder arthroplasty. The purpose of this study was to perform a systematic review and meta-analysis of existing data to explore the relationship between preoperative CSI's and postoperative periprosthetic joint infection (PJI) following shoulder arthroplasty.

METHODS

A literature search was performed on PubMed, Embase, and Web of Science databases through September 29, 2023. Of the 4221 retrieved, 7 studies including 136,233 patients were included for qualitative analysis. Studies describing patients receiving CSI prior to shoulder arthroplasty and the effect on postoperative infection risk were included in the systematic review and subsequent meta-analysis. Assessment of risk of bias was performed using the Methodological Index for Non-Randomized Studies (MINORS) criteria.

RESULTS

Receiving a CSI prior to shoulder arthroplasty was found to have a statistically significant association with increased risk for PJI (odds ratio [OR]: 1.13; 95% confidence interval [CI]: 1.06-1.19; P < .0001). The rate of PJI increased when injections were given closer to the time of surgery. Patients who received an injection at any time point before surgery had a 5.4% risk of PJI compared to 7.9% and 9.0% in patients receiving an injection within 3 months and 1 month of surgery, respectively. This time dependent association however did not reach statistical significance: 1 month OR 1.48; 95% Cl: 0.86-2.53; P = .16, 3 months OR 1.95; 95% Cl: 0.95-4.00; P = .07.

CONCLUSION

The results of this systematic review and meta-analysis demonstrate that patients receiving corticosteroid shoulder injections prior to shoulder arthroplasty may be at an increased risk for PJI postoperatively. While time dependent stratification did not reach statistical significance, our findings indicate a clear trend of increased risk for patients receiving injections closer to surgery.

Preventing Infections in Reverse Shoulder Arthroplasty

PURPOSE OF REVIEW

Reverse shoulder arthroplasty (rTSA) is a commonly performed procedure to treat degenerative conditions of the shoulder. With its growing utilization, techniques to reliably diagnose and treat prosthetic joint infection (PJI) have become increasingly important. In this review we outline the current research and prevention methods of prosthetic joint infection in rTSA. This includes preoperative considerations, intraoperative, and postoperative treatment algorithms.

RECENT FINDINGS

There is currently no established standardized protocol for preoperative infection prevention or post operative management. However, recent studies have identified risk factors for infection, as well as successful prevention techniques that can be implemented to minimize infection risk. Although there is no standardized protocol currently utilized to diagnose and treat shoulder PJI, we outline a potential set of preventative measures and postoperative management strategies that clinicians can use to properly diagnose and treat patients with this difficult condition.

Fungal Shoulder Periprosthetic Infections: A Systematic Review

Background: Data regarding fungal PJIs of the shoulder are scarce. The present systematic review aims to identify and evaluate all published shoulder fungal PJIs in an effort to better understand the diagnostic and therapeutic approach to these infections. Methods: A systematic review according to the PRISMA guidelines was conducted, locating all shoulder fungal PJIs. The initial search located 1435 articles. Data were collected on demographics, the causative fungus, antifungal treatment (AFT), surgical interventions, and infection outcomes. Results: After screening and implementation of the inclusion criteria, a total of 10 articles, including 10 cases, were eligible. The sample's mean age was 62.44 years. Diabetes mellitus was the most common comorbidity (30%), while 70% were immunocompromised. Candida spp. was the most common causative fungus (nine cases; 90%), while all cases were confirmed with cultures. In three cases (30%), there was bacterial co-infection. The mean duration of antifungal treatment (AFT) was 8.4 weeks, while the preferred agent was fluconazole (60% of cases), followed by amphotericin B (30%). Most cases (50%) underwent resection arthroplasty as part of the treatment, while two-stage revision arthroplasty was performed in 30%. Infection's eradication was reported in 90% of the studied cases. Conclusions: The diagnosis and management of fungal periprosthetic shoulder infections are particularly challenging and require a multidisciplinary approach. The combination of antifungal therapy and tailored surgical strategies is crucial, but further research is needed to refine treatment protocols and address the unique considerations in shoulder PJIs.

Chronological changes in the rate of surgical field contamination in the shoulder joint

BACKGROUND

In shoulder surgery, low-virulence bacteria such as Cutibacterium acnes and coagulase-negative staphylococci can cause postoperative infection. However, the degree of sterility during surgery after disinfection is not known, and the efficacy of double skin preparation for such bacteria is unclear. This study aimed to evaluate chronological changes in the surgical field contamination rate in the shoulder joint and to compare single and double skin preparation.

METHODS

In total, 126 shoulders in 121 patients undergoing shoulder surgery (64 men, 62 women; mean age 64 years) were enrolled. Patients were divided into two groups: single skin preparation, where the site was painted with 10% povidone iodine, and double skin preparation, where the site was treated with 1% chlorhexidine gluconate/83% isopropyl alcohol and painted 10% povidone iodine. Swab samples from the axillary and proximal areas in the surgical field were collected chronologically before starting surgery and at 30, 60, and 120 min after starting surgery (MAS). The contamination rate of each sample was compared and detected species were evaluated.

RESULTS

The contamination rate for the axillary area was 48.4%, 85.9%, 95.3%, and 97.1% in the single-preparation group and 32.3%, 72.6%, 87.1%, and 91.2% in the double-preparation group before starting surgery and 30, 60, and 120 MAS, respectively, and that the proximal area was 12.5%, 26.6%, 29.7%, and 35.3% in the single-preparation group and 16.1%, 19.4%, 27.4%, and 38.2% in the double-preparation group, respectively. Significant differences were not seen between the groups by area or time point. Most detected species were Cutibacterium acnes and coagulase-negative staphylococci.

CONCLUSIONS

The incidence of surgical field contamination in shoulder joint was high from immediately after starting surgery. In the axillary area, the contamination rates exceeded 70% from 30 MAS in both groups. Measures against infection should be instituted considering these findings when performing shoulder surgery.

Assessing the Reproducibility of Research Based on the Food and Drug Administration Manufacturer and User Facility Device Experience Data

OBJECTIVE

This article aims to assess the reproducibility of Manufacturer and User Facility Device Experience (MAUDE) data-driven studies by analyzing the data queries used in their research processes.

METHODS

Studies using MAUDE data were sourced from PubMed by searching for "MAUDE" or "Manufacturer and User Facility Device Experience" in titles or abstracts. We manually chose articles with executable queries. The reproducibility of each query was assessed by replicating it in the MAUDE Application Programming Interface. The reproducibility of a query is determined by a reproducibility coefficient that ranges from 0.95 to 1.05. This coefficient is calculated by comparing the number of medical device reports (MDRs) returned by the reproduced queries to the number of reported MDRs in the original studies. We also computed the reproducibility ratio, which is the fraction of reproducible queries in subgroups divided by the query complexity, the device category, and the presence of a data processing flow.

RESULTS

As of August 8, 2022, we identified 523 articles from which 336 contained queries, and 60 of these were executable. Among these, 14 queries were reproducible. Queries using a single field like product code, product class, or brand name showed higher reproducibility (50%, 33.3%, 31.3%) compared with other fields (8.3%, P = 0.037). Single-category device queries exhibited a higher reproducibility ratio than multicategory ones, but without statistical significance (27.1% versus 8.3%, P = 0.321). Studies including a data processing flow had a higher reproducibility ratio than those without, although this difference was not statistically significant (42.9% versus 17.4%, P = 0.107).

CONCLUSIONS

Our findings indicate that the reproducibility of queries in MAUDE data-driven studies is limited. Enhancing this requires the development of more effective MAUDE data query strategies and improved application programming interfaces.

Revision reverse shoulder arthroplasty for the management of baseplate failure: an analysis of 676 revision reverse shoulder arthroplasty procedures

BACKGROUND

Baseplate failure in reverse shoulder arthroplasty (RSA) is a rare but potentially catastrophic complication owing to poor patient outcomes and significant glenoid bone loss. The purpose of this study was to report on the prevalence, causes, and outcomes of revision RSA (rRSA) for baseplate failure or loosening.

METHODS

A retrospective review of our institutional database was performed to identify all patients treated for a failed RSA from 2006 to 2021 who required revision to another RSA (rRSA) performed by a single surgeon. A total of 676 failed RSA procedures were identified, and further analysis identified 46 patients (6.8%) who underwent rRSA for baseplate failure with a confirmed loose baseplate at the time of rRSA. The primary outcome was repeated failure of the reimplanted baseplate following rRSA. The mode of failure associated with baseplate failure was stratified into 1 of 3 groups: aseptic, septic, or traumatic. Twenty-four patients underwent primary revision, and 22 had undergone >1 previous arthroplasty prior to undergoing re-revision. Five patients underwent previous rRSA for baseplate failure performed by an outside surgeon. The criteria for secondary outcome analysis of final American Shoulder and Elbow Surgeons score, Simple Shoulder Test score, and range of motion were met by 32 patients and 23 patients at 1- and 2-year follow-up, respectively.

RESULTS

Three patients (6.5%) had repeated baseplate failure requiring re-revision; 2 had baseplate failure at <1 year with associated periprosthetic infections and underwent conversion to hemiarthroplasty. The third patient experienced traumatic failure at 10 years and underwent successful rRSA. The mean American Shoulder and Elbow Surgeons scores at 1 and 2 years were 62.3 and 61.7, respectively. There was no significant difference in outcomes based on mode of baseplate failure (P = .232) or total arthroplasty burden (P = .305) at 1 year. There were 13 total complications in 11 patients, 5 of which required reoperation for reasons other than baseplate failure.

CONCLUSION

In this study, rRSA for baseplate failure constituted 6.8% of all revisions performed over a period of 15 years. Re-revision for recurrent baseplate failure was required in 3 of 46 patients (6.5%). Complications and reoperation rates were higher than those for primary RSA but outcomes were comparable for revision of failed anatomic shoulder arthroplasty.

Host and microbial characteristics associated with recurrent prosthetic joint infections

Approximately 20% of patients after resection arthroplasty and antibiotic spacer placement for prosthetic joint infection develop repeat infections, requiring an additional antibiotic spacer before definitive reimplantation. The host and bacterial characteristics associated with the development of recurrent infection is poorly understood. A case-control study was conducted for 106 patients with intention to treat by two-stage revision arthroplasty for prosthetic joint infection at a single institution between 2009 and 2020. Infection was defined according to the 2018 Musculoskeletal Infection Society criteria. Thirty-nine cases ("recurrent-periprosthetic joint infection [PJI]") received at least two antibiotic spacers before clinical resolution of their infection, and 67 controls ("single-PJI") received a single antibiotic cement spacer before infection-free prosthesis reimplantation. Patient demographics, McPherson host grade, and culture results including antibiotic susceptibilities were compared. Fifty-two (78%) single-PJI and 32 (82%) recurrent-PJI patients had positive intraoperative cultures at the time of their initial spacer procedure. The odds of polymicrobial infections were 11-fold higher among recurrent-PJI patients, and the odds of significant systemic compromise (McPherson host-grade C) were more than double. Recurrent-PJI patients were significantly more likely to harbor Staphylococcus aureus. We found no differences between cases and controls in pathogen resistance to the six most tested antibiotics. Among recurrent-PJI patients, erythromycin-resistant infections were more prevalent at the final than initial spacer, despite no erythromycin exposure. Our findings suggest that McPherson host grade, polymicrobial infection, and S. aureus infection are key indicators of secondary or persistent joint infection following resection arthroplasty and antibiotic spacer placement, while bacterial resistance does not predict infection-related arthroplasty failure.

Custom-made Glenoid Baseplate and Intra-Operative Navigation in Complex Revision Reverse Shoulder Arthroplasty: A Case Report

Prosthetic instability is one of the most challenging complications to manage when considering reverse shoulder arthroplasty (RSA). Additional tools are available to improve accuracy in planning and execution of arthroplasties, such as 3-dimensional (3D) virtual planning based on computer tomography (CT) scan and intra-operative navigation. We report a case of an 84-year-old male treated for RSA prosthetic instability combined with severe glenoid deformity and bone loss, and subclinical periprosthetic joint infection (PJI). The definitive surgery consisted in implanting a customized metaglene component realized on the basis of the bone defect detected in the 3D-CT scan and implanted with the aid of computer-assisted intra-operative navigation. The patient was periodically followed-up for a year with clinical and radiological evaluations with the absence of further prosthetic dislocations nor PJI, a good overall satisfaction, a satisfying range of motion, and acceptable functional scores (American Shoulder and Elbow Surgeons Score 62, Constant-Murley Score 36). This is the first description, to our knowledge, of a customized glenoid baseplate implanted with the aid of intraoperative navigation. The combined use of 3D-CT planning and intra-operative computer-assisted navigation allows to manage complex cases of prosthetic revision surgery even where extensive bone defects are present.

Implant breakage after shoulder arthroplasty: a systematic review of data from worldwide arthroplasty registries and clinical trials

BACKGROUND

Implant breakage after shoulder arthroplasty is a rare complication after aseptic loosening, infection or persistent pain, resulting in malfunction of the components requiring revision surgery. This correlates with a high burden for the patient and increasing costs. Specific data of complication rates and implant breakage are available in detailed arthroplasty registries, but due to the rare occurrence and possibly underestimated value rarely described in published studies. The aim of this systematic review was to point out the frequency of implant breakage after shoulder arthroplasty. We hypothesized that worldwide arthroplasty registry datasets record higher rates of implant breakage than clinical trials.

METHODS

PubMed, MEDLINE, EMBASE, CINHAL, and the Cochrane Central Register of Controlled Trials database were utilized for this systematic review using the items "(implant fracture/complication/breakage) OR (glenoid/baseplate complication/breakage) AND (shoulder arthroplasty)" according to the PRISMA guidelines on July 3rd, 2023. Study selection, quality assessment, and data extraction were conducted according to the Cochrane standards. Case reports and experimental studies were excluded to reduce bias. The breakage rate per 100,000 observed component years was used to compare data from national arthroplasty registries and clinical trials, published in peer-reviewed journals. Relevant types of shoulder prosthetics were analyzed and differences in implant breakage were considered.

RESULTS

Data of 5 registries and 15 studies were included. Rates of implant breakage after shoulder arthroplasty were reported with 0.06-0.86% in registries versus 0.01-6.65% in clinical studies. The breakage rate per 100,000 observed component years was 10 in clinical studies and 9 in registries. There was a revision rate of 0.09% for registry data and 0.1% for clinical studies within a 10-year period. The most frequently affected component in connection with implant fracture was the glenoid insert.

CONCLUSION

Clinical studies revealed a similar incidence of implant failure compared to data of worldwide arthroplasty registries. These complications arise mainly due to breakage of screws and glenospheres and there seems to be a direct correlation to loosening. Periprosthetic joint infection might be associated with loosening of the prosthesis and subsequent material breakage. We believe that this analysis can help physicians to advise patients on potential risks after shoulder arthroplasty.

LEVEL OF EVIDENCE

III.

Trends in outcomes following aseptic revision shoulder arthroplasty

PURPOSE

As the incidence of anatomic and reverse total shoulder arthroplasty (TSA, RSA) increases, revision procedures will also increase with a corresponding need for counseling patients regarding outcomes. We hypothesized that different revision categories would have different complication profiles depending on both the indication as well as the nature of the prior hardware.

METHODS

A retrospective review of 1773 cases performed at a single tertiary health system utilized case postings and diagnoses to identify revision shoulder arthroplasty cases. Revisions were classified based on the prior hardware present, with basic demographics and other perioperative and postoperative outcomes recorded within the limits of available follow-up.

RESULTS

166 surgical cases involving revision of prior shoulder arthroplasty metal hardware were identified with an average follow-up of 1.0 years. Immediate perioperative outcomes of revision cases were similar relative to the companion cohort of 1607 primary cases. 137 cases (83%) required no further revision surgery, while 19 cases (11%) underwent aseptic revision, and 10 cases (6%) were revised for periprosthetic infection. RSA hardware revised to another RSA had the highest repeat revision rate relative to the other revision categories (32% vs < 14%).

CONCLUSIONS

Revision of reverse shoulder arthroplasty to a repeat reverse has the highest rate of subsequent all-cause revision, and these repeat revisions often occurred for periprosthetic infection. Despite a relatively high long-term complication rate following revision shoulder arthroplasty, immediate perioperative outcomes remain similar to primary cases, providing some preliminary evidence for policymakers considering inclusion in future value-based care models.

LEVEL OF EVIDENCE

Level III Treatment Study.

Can convertible metal-backed glenoid components replace cemented polyethylene glenoid components in anatomical total shoulder arthroplasty?

BACKGROUND

Anatomical total shoulder arthroplasty (aTSA) has been used to manage degenerative diseases such as primary osteoarthritis. An increase in the use of this procedure has led to several developments in humeral and glenoid components to improve patient outcomes. This study aimed to compare clinical and radiological outcomes of the newly-introduced convertible metal-backed glenoid components with cemented polyethylene glenoid components in aTSA, and to determine whether the new component would be comparable to a conventional one for reducing the burden of future revision or conversion surgeries.

METHODS

Medical records of fifty patients who underwent aTSA with at least two years of follow-up were retrospectively reviewed. Eighteen patients received convertible metal-backed glenoid components with vitamin E1-coated liner (MB group), while thirty-two patients received conventional cemented polyethylene glenoid components (PE group). Pre- and postoperative clinical and radiological outcomes (acromion-greater tuberosity angle [AGA] and humeral lateral offset [LO]) at final follow-up were assessed. Radiolucent lines (RLLs) and loosening around the humeral and glenoid components were also evaluated.

RESULTS

Clinical outcomes improved after surgery in both groups (all p < 0.001). The arc of rotation measured by AGA improved postoperatively in both groups (all p < 0.001), and AGA and LO were not different according to the type of glenoid components (all p > 0.05). Overall complication rates including RLLs of PE and MB groups were 43.8% (14/32) and 16.7% (3/18), respectively (p = 0.031). Although the PE group had more RLLs than did the MB group (p < 0.05), related symptoms and/or glenoid implant loosening were not observed in both groups. Subscapularis failure occurred in two patients in the PE group and in one in the MB group.

CONCLUSION

The convertible metal-backed glenoid implant with vitamin E1-coated liner may be a good alternative for considering the potential for an easier conversion to reverse total shoulder arthroplasty.

Preventing and Treating Infection in Reverse Total Shoulder Arthroplasty

PURPOSE OF REVIEW

Periprosthetic infection after shoulder arthroplasty is relatively uncommon though associated with severe long-term morbidity when encountered. The purpose of the review is to summarize the recent literature regarding the definition, clinical evaluation, prevention, and management of prosthetic joint infection after reverse shoulder arthroplasty.

RECENT FINDINGS

The landmark report generated at the 2018 International Consensus Meeting on Musculoskeletal Infection has provided a framework for diagnosis, prevention, and management of periprosthetic infections after shoulder arthroplasty. Shoulder specific literature with validated interventions to reduce prosthetic joint infection is limited; however existing literature from retrospective studies and from total hip and knee arthroplasty allows us to make relative guidelines. One and two-stage revisions seem to demonstrate similar outcomes; however, no controlled comparative studies exist limiting the ability to make definitive recommendations between the two options. We report on recent literature regarding the current diagnostic, preventative, and treatment options for periprosthetic infection after shoulder arthroplasty. Much of the literature does not distinguish between anatomic and reverse shoulder arthroplasty, and further high-level shoulder specific studies are needed to answer questions generated from this review.

Risk Factors for Stiffness Requiring Intervention After Ream-and-Run Arthroplasty

Ream-and-run arthroplasty can improve pain and function in patients with glenohumeral arthritis while avoiding the complications and activity restrictions associated with a prosthetic glenoid component. However, stiffness is a known complication after ream-and-run arthroplasty and can lead to repeat procedures such as a manipulation under anesthesia (MUA) or open surgical revision. The objective of this study was to determine risk factors associated with repeat procedures indicated for postoperative stiffness after ream-and-run arthroplasty.

Methods

We conducted a retrospective review of our shoulder arthroplasty database to identify patients who underwent ream-and-run arthroplasty and determined which patients underwent subsequent repeat procedures (MUA and/or open revision) indicated for postoperative stiffness. The minimum follow-up was 2 years. We collected baseline demographic information and preoperative and 2-year patient-reported outcome scores and analyzed preoperative radiographs. Univariate and multivariate analyses determined the factors significantly associated with repeat procedures to treat postoperative stiffness.

Results

There were 340 patients who underwent ream-and-run arthroplasty. The mean Simple Shoulder Test (SST) scores for all patients improved from 5.0 ± 2.4 preoperatively to 10.2 ± 2.6 postoperatively (p < 0.001). Twenty-six patients (7.6%) underwent open revision for stiffness. An additional 35 patients (10.3%) underwent MUA. Univariate analysis found younger age (p = 0.001), female sex (p = 0.034), lower American Society of Anesthesiologists (ASA) class (p = 0.045), posterior decentering on preoperative radiographs (p = 0.010), and less passive forward elevation at the time of discharge after ream-and-run arthroplasty (p < 0.001) to be significant risk factors for repeat procedures. Multivariate analysis found younger age (p = 0.040), ASA class 1 compared with class 3 (p = 0.020), and less passive forward elevation at discharge (p < 0.001) to be independent risk factors for repeat procedures. Of the patients who underwent open revision for stiffness, 69.2% had multiple positive cultures for Cutibacterium.

Conclusions

Younger age, ASA class 1 compared with class 3, and less passive forward elevation in the immediate postoperative period were independent risk factors for repeat procedures to treat postoperative stiffness after ream-and-run arthroplasty.

Level of Evidence

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

Revision of total shoulder arthroplasty to hemiarthroplasty: results at mean 5-year follow-up

BACKGROUND

Although there is a trend to manage failed anatomic total shoulder arthroplasties (aTSA) with revision to a reverse total shoulder arthroplasty, such revisions can be complicated by difficulties in baseplate fixation, instability, and acromial stress fractures. Some cases of failed aTSA may be safely revised to a hemiarthroplasty (HA). The objectives of this study were to report patient-reported outcomes after conversion from aTSA to HA and assess patient and shoulder characteristics associated with a successful outcome.

METHODS

Patients who underwent revision from aTSA to HA between 2009 and 2018 were contacted. Patient demographics, surgical history, intraoperative findings, and microbiology results were collected. Patient-reported outcomes were collected with minimum 2-year follow-up. Preoperative radiographic characteristics were reviewed for component positioning and component loosening. Patients with a clinically significant improvement exceeding the minimal clinically important difference (MCID) of the Simple Shoulder Test (SST) were compared with those patients who did not improve past the MCID.

RESULTS

Twenty-nine patients underwent conversion from aTSA to HA with a mean follow-up of 4.5 ± 1.8 years. Intraoperative glenoid or humeral component loosening was found in all 29 patients. Pain improved in 25 of 30 patients (87%), and mean pain scores improved from 6.2 ± 2.3 to 3.1 ± 2.4 (P < .001). SST scores improved from 4.1 ± 3.1 to 7.3 ± 3.2 (P < .001), and 18 of 29 patients (62%) had improvement above the SST MCID threshold of 2.4. The mean American Shoulder and Elbow Surgeons score at the latest follow-up was 64 ± 19, and the Single Assessment Numeric Evaluation score was 65 ± 23. Twenty-two of 29 (76%) patients were satisfied with the procedure. Four patients (14%) required conversion to total shoulder arthroplasty-2 to anatomic and 2 to reverse. An additional 3 patients (10%) had a revision HA performed. No significant differences in patient or shoulder characteristics were found in those patients who improved greater than the MCID of the SST compared patients who improved less than the MCID of the SST. Fifty-nine percent of patients had ≥2 positive cultures with the same bacteria, and 82% of these were with Cutibacterium. Seven of 8 patients (88%) with a loose humeral component had ≥2 positive cultures with the same bacteria.

DISCUSSION

Component loosening is a common failure mode after aTSA. Revision to HA can improve pain and patient-reported outcomes in most patients.

Predictors of success following single-stage revision shoulder arthroplasty: results at a mean of five year follow-up in one hundred and twelve patients

PURPOSE

The objective was to determine factors associated with a successful outcome at a minimum of two years after revision of a failed shoulder arthroplasty.

METHODS

We conducted a retrospective study of revision shoulder arthroplasties performed over a ten year period and collected patient-reported outcome data and re-revision data. A successful outcome was defined by improvement greater than the minimal clinically important difference (MCID) for the Simple Shoulder Test (SST).

RESULTS

One hundred twelve patients with average follow-up of five years were included. Improvement of VAS pain scores (6.6 ± 2.3 to 2.9 ± 2.6) and SST scores (2.7 ± 2.6 to 6.6 ± 3.3) were significant (p < 0.001). Males were more likely to have a successful outcome than females (p = 0.01).

CONCLUSION

Two-thirds of patients experienced clinically significant improvement at a minimum of two years after revision shoulder arthroplasty. Male sex was the strongest independent predictor of a successful outcome.

Development of a machine learning algorithm to identify total and reverse shoulder arthroplasty implants from X-ray images

Introduction

Demand for total shoulder arthroplasty (TSA) has risen significantly and is projected to continue growing. From 2012 to 2017, the incidence of reverse total shoulder arthroplasty (rTSA) rose from 7.3 cases per 100,000 to 19.3 per 100,000. Anatomical TSA saw a growth from 9.5 cases per 100,000 to 12.5 per 100,000. Failure to identify implants in a timely manner can increase operative time, cost and risk of complications. Several machine learning models have been developed to perform medical image analysis. However, they have not been widely applied in shoulder surgery. The authors developed a machine learning model to identify shoulder implant manufacturers and type from anterior-posterior X-ray images.

Methods

The model deployed was a convolutional neural network (CNN), which has been widely used in computer vision tasks. 696 radiographs were obtained from a single institution. 70% were used to train the model, while evaluation was done on 30%.

Results

On the evaluation set, the model performed with an overall accuracy of 93.9% with positive predictive value, sensitivity and F-1 scores of 94% across 10 different implant types (4 reverse, 6 anatomical). Average identification time was 0.110 s per implant.

Conclusion

This proof of concept study demonstrates that machine learning can assist with preoperative planning and improve cost-efficiency in shoulder surgery.

Clinical and Radiologic Outcomes after Anatomical Total Shoulder Replacement Using a Modular Metal-Backed Glenoid after a Mean Follow-Up of 5.7 Years

Background: Glenoid wear is a common complication of anatomical total shoulder arthroplasty (aTSA) with a metal-backed glenoid (MBG), and the clinical and radiological results of historical implants are poor. The aim of this work was to evaluate the clinical and radiological results of 25 participants as well as the longevity after implantation of an anatomic shoulder prosthesis with a recent, modular cementless flat metal-backed glenoid component after a mean follow-up of 5.7 years. Methods: Clinically, the Simple Shoulder Test (SST), UCLA Activity Score (UCLA), and Constant Murley Score (CMS) were evaluated. Radiographically, the radiolucent lines (RLs), humeral head migration (HHM), and lateral glenohumeral offset (LGHO) were assessed. Survival was calculated with Kaplan−Meier curves and life-table analysis. Results: The mean CMS at follow-up was 46.2 points (range: 14−77; SD: 19.5). In terms of the SST score, the average value was 6.5 points (range: 1−10; SD: 3.5). The UCLA activity score showed a mean value of 5.9 points (range: 1−9; SD: 2.1). There were 17 revisions after a mean follow-up of 68.2 months (range: 1.8−119.6; SD: 27.9). HHM occurred in every patient, with a mean measurement of 6.4 mm (range: 0.5−13.4; SD: 3.9; p < 0.0001). The mean LGHO between the initial postoperative and follow-up images was 2.6 mm (range: 0−4.0; SD: 1.5; p < 0.0001). RLs were found in 22 patients (88%) around the glenoid and in 21 patients (84%) around the humeral head prosthesis. Conclusion: The clinical and radiographic outcomes after metal-backed glenoids were poor at 2.2 to 8.4 years of follow-up. We determined devastating survival in the majority of cases (68%), with mostly inlay wear (71%) as the main reason that led to revision surgery. The use of metalback genoids cannot be recommended based on the data of this study.

Adverse Events Associated With Robotic-Assisted Joint Arthroplasty: An Analysis of the US Food and Drug Administration MAUDE Database

BACKGROUND

The use of robotic assistance in arthroplasty is increasing; however, the spectrum of adverse events potentially associated with this technology is unclear. Improved understanding of the causes of adverse events in robotic-assisted arthroplasty can prevent future incidents and enhance patient outcomes.

METHODS

Adverse event reports to the US Food and Drug Administration Manufacturer and User Facility Device Experience database involving robotic-assisted total hip arthroplasty (THA), total knee arthroplasty (TKA), and partial knee arthroplasty were reviewed to determine causes of malfunction and related patient impact.

RESULTS

Overall, 263 adverse event reports were included. The most frequently reported adverse events were unexpected robotic arm movement for TKA (59/204, 28.9%) and retained registration checkpoint for THA (19/44, 43.2%). There were 99 reports of surgical delay with an average delay of 20 minutes (range 1-120). Thirty-one cases reported conversion to manual surgery. In total, 68 patient injuries were reported, 7 of which required surgical reintervention. Femoral notching (12/36, 33.3%) was the most common for TKA and retained registration checkpoint (19/28, 67.9%) was the most common for THA. Although rare, additional reported injuries included femoral, tibial, and acetabular fractures, MCL laceration, additional retained foreign bodies, and an electrical burn.

CONCLUSION

Despite the increasing utilization of robotic-assisted arthroplasty in the United States, numerous adverse events are possible and technical difficulties experienced intraoperatively can result in prolonged surgical delays. The events reported herein seem to indicate that robotic-assisted arthroplasty is generally safe with only a few reported instances of serious complications, the nature of which seems more related to suboptimal surgical technique than technology. Based on our data, the practice of adding registration checkpoints and bone pins to the instrument count of all robotic-assisted TJA cases should be widely implemented to avoid unintended retained foreign objects.

The FDA and Ensuring Safety and Effectiveness of Devices, Biologics, and Technology

Orthopaedic devices account for nearly 20% of all devices on the market, with more than 600 novel orthopaedic devices cleared or approved by the FDA for marketing in the United States annually. Advances in technology and biologic therapies offer tremendous potential for patients with musculoskeletal ailments; however, it is important that the safety and effectiveness of these products be assessed to safeguard the public health. The FDA uses multiple different premarket pathways for devices, biologics, and combination products based on perceived risk of the novel product. More than 97% of orthopaedic devices go through the FDA's 510(k) pathway, which does not require clinical trials. The remaining high-risk devices must receive premarket approval and submit clinical trial data demonstrating safety and effectiveness. Similarly, high-risk biologics must obtain a biologics license application by submitting clinical trial data. Postmarketing surveillance strategies, including extended clinical trials or real-world evidence from registries, are increasingly being relied on by the FDA to expedite approval while also improving its capacity to identify problematic products.

Do preoperative factors and implant design features influence humeral stem extraction efforts?

BACKGROUND

Variations in humeral component designs in hemiarthroplasty and anatomic total shoulder arthroplasty cases can impact the degree of difficulty during a revision surgery that necessitates the removal of the humeral stem. However, no metric exists to define stem extraction effort nor to identify associated factors that contribute to extraction difficulty. The purpose of this study is to describe a method to quantify stem extraction difficulty and to define features that will impact the effort during stem removal.

METHODS

This was a retrospective review of 58 patients undergoing revision of hemiarthroplasty or anatomic total shoulder arthroplasty requiring stem extraction. Each included patient had existing preoperative radiographic examination, an intraoperative video of the stem removal process, and explants available for analysis by 3 surgeons. The following factors were assessed for the impact on extraction difficulty: (1) preoperative features such as cement use, fill of proximal humerus, and stem design features; (2) intraoperative data on extraction time and bone removal; and (3) postoperative findings related to extraction artifacts (EAs). A scoring system was established to distinguish easy (Easy group) and difficult (Difficult group) stem removal cases and further used to identify the features that may affect intraoperative difficulty of stem removal.

RESULTS

The Difficult group accounted for 26% (15/58) of the study population with an 18-minute average stem extraction time, average EA count of 69, and 35 mm of bone removed. The Easy group accounted for 74% (43/58) of patients, with a 4-minute average extraction time, average EA count of 23, and 10 mm of bone removed. Logistic regression model was able to correctly classify 82% of the cases, explaining 26.7% of the variance in humeral stem removal with cement and proximal coating variables. The likelihood of cemented stem removal being difficult is 5 times greater compared to an uncemented stem, and having proximal coating doubles the likelihood of a difficult stem removal compared to cases with no coating.

CONCLUSIONS

Quantifying stem extraction difficulty is possible with intraoperative video as well as explant analysis. Preoperative features of the fixation type and specific features of stem design such as proximal coating will impact difficulty of stem extraction.

Early outcomes of augmented glenoid components in anatomic total shoulder arthroplasty: a systematic review

BACKGROUND

The objective was to evaluate the short-term clinical and radiological outcomes following augmented anatomic total shoulder arthroplasty in patients with posterior glenoid deficiency.

METHODS

An electronic search of EMBASE, MEDLINE, and PubMed identified studies reporting clinical and radiographic outcomes following augmented anatomic total shoulder arthroplasty among patients with posterior glenoid deficiency.

RESULTS

Nine studies including 312 shoulders underwent anatomic total shoulder arthroplasty using an augmented glenoid implant between 2015 and 2020. A statistically significant improvement in range of motion (ROM), visual analog scale (VAS), American Shoulder & Elbow Surgeons (ASES), Constant, University of California - Los Angeles and Simple Shoulder Test (SST) scores was demonstrated at mean follow-up of 37.1 months. Glenoid retroversion improved from 21.8° to 9.5°. At final follow-up, radiolucency was reported in 35.1% of shoulders. The 16° full-wedge augment led to higher and more severe radiographic lucency, while high peg perforation rates (44%) were observed among 5-mm augment stepped implants. The overall rate of complication was 2.6%. Rate of revision surgery was 1.9%.

CONCLUSIONS

Overall, early- to mid-term outcomes following augmented anatomic total shoulder arthroplasty for posterior glenoid deficiency demonstrate good to excellent overall clinical results. More radiographic and clinical failures were reported in larger full wedge (16°) augments and stepped augments (5 mm). Prospective studies examining mid- and long-term outcomes will help further elucidate safety and efficacy of these relatively new implants.

Primary reverse total shoulder arthroplasty performed for glenohumeral arthritis: does glenoid morphology matter?

BACKGROUND

Indications for reverse total shoulder arthroplasty (RTSA) have expanded to include primary glenohumeral osteoarthritis (GHOA) with an intact rotator cuff. Limited evidence exists on RTSA in patients with primary GHOA and no posterior glenoid wear (Walch A1, A2, and B1 morphologies). The purpose of this retrospective cohort study was to determine if glenoid morphology is associated with clinical outcomes in patients undergoing RTSA for primary GHOA.

METHODS

A retrospective review of prospectively collected data was performed in patients undergoing primary RTSA for GHOA with a minimum of 2-year clinical follow-up. Preoperative computed tomography and magnetic resonance imaging were used to categorize glenoid morphology as described by the modified Walch classification. Pre- and postoperative American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), Single Assessment Numeric Evaluation (SANE), visual analog scale (VAS) pain scores, and range of motion (ROM) measurements were compared across Walch glenoid subtypes. The percentage of patients that reached previously established clinically significant thresholds for minimal clinically important difference (MCID) and substantial clinical benefit (SCB) was also comparatively assessed. Multivariable analysis was used to evaluate the association between glenoid morphology and postoperative ASES score while controlling for potentially confounding variables.

RESULTS

Of the 247 consecutive patients, 197 were available at a minimum 2-year follow-up (80%). Significant improvements were seen in ASES, VAS pain, SANE, and ROM from baseline to final postoperative follow-up in the combined patient cohort (all P < .001). Most (98.0%) patients reached MCID, and 90.9% of patients reached SCB for ASES threshold. No significant differences were found among Walch subtypes in terms of preoperative to postoperative improvement in ASES (P = .39), SANE (P = .4), VAS pain (P = .49), forward elevation (P = .77), external rotation (P = .45), or internal rotation (P= 0.1). The only significant difference in postoperative outcomes between Walch glenoid subtypes was higher postoperative ASES scores among type B3 glenoids compared with type A1 glenoids (P = .03) on univariate analysis. However, no individual Walch glenoid subtype was associated with lower postoperative ASES scores on multivariable analysis (P > .05).

CONCLUSION

Primary RTSA provides excellent short-term outcomes in patients with glenohumeral arthritis with intact rotator cuff, regardless of the degree of preoperative glenoid deformity. Surgeons can use these data to support the use of RTSA for glenohumeral arthritis in a more standardized way.

Incidence, Risk Factors, Prevention, and Management of Peripheral Nerve Injuries Following Shoulder Arthroplasty

In this article, the authors review the incidence and causes of iatrogenic peripheral nerve injuries following shoulder arthroplasty and provide preventative measures to decrease nerve injury rate and management options. They describe common direct and indirect causes of injury such as laceration and retractor use versus arm positioning and lengthening, respectively. Preventative measures include an understanding of anatomy and high-risk locations in the shoulder, minimizing extreme ranges of arm motion and utilization of intraoperative nerve monitoring. Lastly, the authors review diagnosis and management of neurologic symptoms including how and when to use electrodiagnostic studies, nerve grafts, transfers, or muscle/tendon transfers.

Postoperative stiffness after reverse total shoulder arthroplasty

PURPOSE

The purpose of this study was to evaluate the rate and risk factors for stiffness after reverse shoulder arthroplasty and the ramifications on the patient-reported outcomes.

METHOD

A consecutive series of patients who underwent reverse shoulder arthroplasty were prospectively followed for one year. Passive range of motion was measured preoperatively and at regular intervals postoperatively. Patients with passive forward elevation of less than 100° or passive external rotation of less than 30° were defined as stiff. Radiographic parameters and postoperative patient-reported outcome scores were collected.

RESULTS

Seventy-six patients were available for review. The prevalence of postoperative stiffness following reverse shoulder arthroplasty was 47% at three months, 31% at six months, and 25% at one year. Preoperative shoulder stiffness was associated with three-month postoperative stiffness only. In patients with one-year stiffness, smaller (p = 0.03) and less lateralized glenospheres (p = 0.024) were more common. Stiffness was not associated with one-year patient-reported outcome scores.

CONCLUSION

Stiffness is common after reverse shoulder arthroplasty and often improves at one-year after surgery. Implant design and selection may be important determinants of passive range of motion. While stiffness does not appear to influence patient-reported outcome scores, one of four patients will potentially have stiffness one year following reverse shoulder arthroplasty.Level of evidence: Level III; retrospective study.

A cross-sectional analysis of 284 complications for lumbar disc replacements from medical device reports maintained by the United States Food and Drug Administration

BACKGROUND CONTEXT

Lumbar disc replacement (LDR) is a motion sparing procedure for degenerative disc disease. When compared to lumbar fusion, this procedure may reduce complications, reoperations, operative time, and length of stay. However, the extent of overall complications related to LDR has not been well defined in the literature.

PURPOSE

Demonstrate the complication profile of popular LDR implants reported to the Food and Drug Administration (FDA).

STUDY DESIGN

Retrospective database review.

PATIENT SAMPLE

Nationwide database of reported complications related to LDR products from patients throughout the country.

OUTCOME MEASURES

Complications related to LDR.

METHODS

Data files from January 1, 2004 to April 1, 2021 were queried using the publicly accessible Manufacturer and User Facility Device Experience (MAUDE) database and Alternative Summary Reporting program. Three LDR ("Charité," "Prodisc-L," and "Activ L") products were analyzed for complications. Data collected included the date the reports were received by the FDA, the type of complication, complication event description, and the source of the report. The complication event description was utilized to determine the completion of the investigation. Entries with insufficient information were excluded. Complications were further divided into two categories, device and non-device related.

RESULTS

A total of 431 complication entries were found between January 1, 2004, and April 1, 2021. After screening for duplicates and events with insufficient information there were 284 total complications. The total complications were then further divided into implant and non-implant related. The five most common overall complications were lumbar pain (49 entries, 17.25%), migration of implant (42 entries, 14.78%), polyethylene dislodged (37 entries, 13.0%), insertion of device problem (37 entries, 13.0%), device handling problem (12 entries, 4.22%). The most common implant related complication, along with the number of MAUDE entries for each implant was migration of implant for Charité (n=6); Migration of implant for ActivL (n=24); Polyethylene dislodged for ProdiscL (n=32). Of the 284 total complications analyzed, 86 (30.28%) of the entries were deemed "investigation completed." The majority of reports were submitted from the manufacturer and company representative (66.2%, 14.8 % respectively). There were no entries related to LDR within the Alternative Summary Reporting search.

CONCLUSIONS

This study outlined the complications of LDR implants from the MAUDE database which have not always been highlighted in previously published studies. The findings of this study provide insight into the potential targets for improvement in future LDR design and surgical techniques to reduce complications and ensure the safe utilization of these implants.

Primary versus revision total shoulder arthroplasty: comparing relative value and reimbursement trends

Background

Total shoulder arthroplasty (TSA) has been demonstrated to be an effective treatment for multiple shoulder pathologies. The purpose of our study was to compare the relative value units (RVUs) per minute of surgical time for primary and revision TSA.

Methods

The American College of Surgeons National Surgical Quality Improvement Program database was queried to identify patients that underwent primary TSA, one-component revision TSA, and two-component revision TSA between January 1, 2015 and December 31, 2017 using current procedure terminology codes. RVUs were divided by mean operative time for each procedure to determine the amount of revenue generated per minute. Rates were compared between the groups using a one-way analysis of variance with post-hoc Tukey test. Statistical significance was set at p<0.05.

Results

When dividing compensation by surgical time, we found that two-component revision generated more compensation per minute compared to primary TSA (0.284±0.114 vs. 0.239±0.278 RVU per minute or $10.25±$4.11 vs. $8.64±$10.05 per minute, respectively; p=0.001).

Conclusions

The relative value of revision TSA procedures is weighted to account for the increased technical challenges and time associated with these procedures. This study confirms that reimbursement is higher for revision TSA compared to primary TSA.

Surgical Trends of Shoulder Arthroplasty: Nationwide Epidemiologic Study in South Korea

Background

The aim of this study was to determine the nationwide shoulder arthroplasty trends in South Korea based on an analysis of nationwide data acquired from the Korean Health Insurance Review and Assessment Service (HIRA).

Methods

We analyzed a nationwide database acquired from the HIRA that covered 2008 to 2017. International Classification of Diseases, 10th Revision (ICD-10) codes and procedure codes were used to identify patients who underwent shoulder arthroplasty, including total shoulder arthroplasty (TSA), hemiarthroplasty (HA), and revision shoulder arthroplasty.

Results

From 2008 to 2017, a total of 19,831 shoulder arthroplasties were performed; there were 16,162 TSAs and 3,669 hemiarthroplasties. During the 10-year study period, there was an exponential increase in the incidence of TSA (from 513 cases in 2008 to 3,583 cases in 2017), while the number of hemiarthroplasties remained steady. The most common diagnoses for TSA were rotator cuff tears (6,304 cases, 39.0%) and osteoarthritis (6,589 cases, 40.8%) for all 9 years. Osteoarthritis was the most common reason for TSA during the first 3 years (2008-2010), but rotator cuff tears ultimately surpassed osteoarthritis during the last 3 years (2015-2017). HA was performed to treat proximal humerus fracture (1,770 cases, 48.2%) and osteoarthritis (774 cases, 21.1%). In terms of hospital types, the rate of TSA in hospitals with 30-100 inpatient beds increased from 21.83% to 46.27%, while the rates of the other types of surgery decreased. A total of 430 revision surgeries were performed during the study period, and infection (152 cases, 35.3%) was the most common reason for revision surgery.

Conclusions

Overall, the total count and incidence of TSA, unlike HA, increased rapidly between 2008 and 2017 in South Korea. Moreover, at the end of the study period, nearly half of the TSAs were performed in small hospitals (30 to 100 beds). Rotator cuff tears were the leading cause of TSA at the end of the study period. These findings revealed an explosive increase in reverse TSA surgery.

Early fixation of the humeral component in stemless total shoulder arthroplasty : a radiostereometric and clinical study with 24-month follow-up

AIMS

Stemless humeral implants have been developed to overcome stem-related complications in total shoulder arthroplasty (TSA). However, stemless implant designs may hypothetically result in less stable initial fixation, potentially affecting long-term survival. The aim of this study is to investigate early fixation and migration patterns of the stemless humeral component of the Simpliciti Shoulder System and to evaluate clinical outcomes.

METHODS

In this prospective cohort study, radiostereometric analysis (RSA) radiographs were obtained in 24 patients at one day, six weeks, six months, one year, and two years postoperatively. Migration was calculated using model-based RSA. Clinical outcomes were evaluated using the visual analogue scale (VAS), the Oxford Shoulder Score (OSS), the Constant-Murley Score (CMS), and the Disabilities of the Arm, Shoulder and Hand (DASH) score.

RESULTS

At two years, median translation along the x-, y-, and z-axis was -0.12 mm (interquartile range (IQR) -0.18 to 0.02), -0.17 mm (IQR -0.27 to -0.09), and 0.09 mm (IQR 0.02 to 0.31). Median rotation around the x-, y-, and z-axis was 0.12° (IQR -0.50 to 0.57), -0.98° (IQR -1.83 to 1.23), and 0.09° (IQR -0.76 to 0.30). Overall, 20 prostheses stabilized within 12 months postoperatively. Four prostheses showed continuous migration between 12 and 24 months. At two-year follow-up, with the exception of one revised prosthesis, all clinical scores improved significantly (median VAS difference at rest: -3.0 (IQR -1.5 to -6.0); OSS 22.0 (IQR 15.0 to 25.0); CMS 29.5 (IQR 15.0 to 35.75); and DASH -30.0 (IQR -20.6 to -41.67) (all p < 0.001)) with the exception of one revised prosthesis.

CONCLUSION

In conclusion, we found that 20 out of 24 implants stabilized within 12 months postoperatively. The significance of continuous migration in four implants is unclear and future research on the predictive value of early migration for future loosening in TSA is required. Clinical results revealed a clinically relevant improvement. Cite this article: Bone Joint J 2022;104-B(1):76-82.

Prior shoulder surgery and rheumatoid arthritis increase early risk of infection after primary reverse total shoulder arthroplasty

Background

Reverse total shoulder arthroplasty (RTSA) has become an increasingly popular surgery for patients with rotator cuff arthropathy, unreconstructible proximal humeral fracture, and end-stage glenohumeral arthritis. The increased annual volume of RTSAs has resulted in more postoperative complications and revision rates between 3.3% and 10.1%. Postoperative infection is one of the most common complications requiring revision surgery after primary RTSA. This study assesses patient-specific risk factors for development of early infection after primary RTSA in a single high-volume shoulder arthroplasty institution.

Methods

From 2014 to 2019, 902 consecutive primary RTSAs were performed for surgical treatment of rotator cuff arthropathy, glenohumeral arthritis, inflammatory arthropathy, and/or dislocation. Excluding proximal humeral or scapula fractures, 756 cases met the inclusion criteria and had a minimum of 3-month follow-up. All surgeries were performed using the same surgical technique and received similar antibiotic prophylaxis. Age, patient demographics, medical history, smoking history, and prior ipsilateral shoulder treatment and/or surgery were recorded. Multivariable logistic regression analysis was used to determine risk factors associated with development of postoperative shoulder infection.

Results

Thirty-five patients did not meet minimum follow-up criteria and were lost to follow-up. Overall, of 721, 22 patients (3%) developed a postoperative ipsilateral shoulder infection. Previous nonarthroplasty surgery and history of rheumatoid arthritis were significantly associated with the development of postoperative shoulder infection. Amongst 196 patients who had previous nonarthroplasty shoulder surgery, there were 12 postoperative shoulder infections (6%) compared with those without previous shoulder surgery (10 of 525, 2%) (P = .003). Among 58 patients with rheumatoid arthritis, there were 5 postoperative shoulder infections (9%) compared with patients without rheumatoid arthritis (17 of 663, 3%) (P = .010). Patient age, gender, smoking status, history of diabetes mellitus, history of cancer/immunosuppression, and prior cortisone injection did not demonstrate significant associations with the development of postoperative infection.

Conclusion

Prior nonarthroplasty shoulder surgery and/or rheumatoid arthritis are independently associated with the development of postoperative infection after primary RTSA. Patients who demonstrate these risk factors should be appropriately evaluated and preoperatively counseled before undergoing primary RTSA. Strong consideration should be given to avoid minimally invasive nonarthroplasty surgery as a temporizing measure to delay definitive RTSA.

Intermediate to long term results of stemless metaphyseal reverse shoulder arthroplasty: A five to nine year follow-up

BACKGROUND

Shoulder arthroplasty incidence is increasing as is the volume of revision surgeries. Revision surgery is easier if humeral bone stock is preserved with minimal bone defects and osteolysis. This has led to an increased focus on the development of various short stemmed and stemless implants which provides stable fixation whilst preserving humeral bone stock.

PURPOSE

To review the medium to long term clinical and radiological outcomes, complications and survival rates of a stemless reverse shoulder prosthesis.

PATIENTS AND METHOD

Patients with a minimum follow-up of 60 months following a reverse stemless shoulder arthroplasty were deemed eligible. Clinical and radiological data on twenty-one patients operated between 2009 and 2014 were recorded prospectively. Survivorship and patient recorded symptoms with the end point of revision surgery were recorded.

RESULTS

Mean follow-up of 78 months (60-114 months). Mean range of active elevation was 136° (80-170°). Mean range of active abduction and active external rotation was 122° (70-170°) and 47° (10-75°) respectively. Mean Oxford score improved from 12 pre-operatively to 44 at final follow up (p < 0.0001). Mean Constant Murley Score improved from 18 to 72 (p < 0.0001). Mean ADLEIR score of 13 pre-operatively increased to 32 post-operatively (p < 0.0001). Notching was seen in 23.5% of cases and no radiolucent areas were observed around the glenoid component. There were two cases of post traumatic peri-prosthetic fractures that were managed conservatively and one case of deep-seated infection that required a washout. The survivorship at the most recent follow-up was 100%.

CONCLUSION

The advantages of bone preservation with the stemless metaphyseal prosthesis combined with encouraging medium to long term clinical and radiological results are very promising, particularly with the improved post-operative patient satisfaction scores. This is the first study that reports the results with a minimum of 5 year follow-up and has the longest mean follow-up period.

CLINICAL RELEVANCE

The reverse stemless shoulder prosthesis is an effective and reliable option for elective shoulder arthroplasty.

Analysis of 408 Total Ankle Arthroplasty Adverse Events Reported to the US Food and Drug Administration From 2015 to 2018

Background. Total ankle arthroplasty (TAA) use has increased with newer generation implants. Current reports in the literature regarding complications use data extracted from high-volume centers. The types of complications experienced by lower-volume centers may not be reflected in these reports. The purpose of this study was to determine a comprehensive TAA adverse event profile from a mandatory-reporting regulatory database. Methods. The US Food and Drug Administration's Manufacturer and User Facility Device Experience (MAUDE) database was reviewed from 2015 to 2018 to determine reported adverse events for approved implants. Results. Among 408 unique TAA device failures, the most common modes of failure were component loosening (17.9%), intraoperative guide or jig error (15.4%), infection (13.7%), and cyst formation (12.7%). In addition, the percentage distribution of adverse event failure types differed among implants. Conclusion. The MAUDE database is a publicly available method that requires mandatory reporting of approved device adverse events. Using this report, we found general agreement in types of complications reported in the literature, although there were some differences, as well as differences between implants. These data may more accurately reflect a comprehensive profile of TAA complications as data were taken from a database of all device users rather than only high-volume centers.Levels of Evidence: NA.

Case Report: Watching and Waiting? A Case of Incomplete Glenosphere Seating With Spontaneous Reversal in Reverse Shoulder Arthroplasty

Introduction: Reverse shoulder arthroplasty is a useful procedure with broadening applications, but it has the best outcomes when used for rotator cuff tear arthropathy. However, this procedure is not without complications. While scapular notching and aseptic loosening are more common complications that have been extensively studied in the literature, dissociation of the glenoid component and incomplete glenosphere seating has not received much attention. Specifically, little research has explored appropriate management of incomplete seating of the glenosphere component, and no gold standard for treatment of this complication has emerged.

Methods: In the case described here, an elderly patient with an incompletely seated glenosphere component post-operatively opted to pursue conservative management in order to avoid revision surgery if possible.

Results: The partially engaged, superiorly directed components in this case exhibited spontaneous complete and symmetric seating of the glenosphere between six and twelve months post-operatively, indicating that conservative management of this complication in low-demand patients may be a viable option to avoid the risks associated with revision surgery.

Conclusion: Further research should be pursued to explore what patient and prosthesis design factors may be suited to observation with serial radiographs when incomplete seating of the glenosphere component occurs.

Primary reverse shoulder arthroplasty in patients with metabolic syndrome is associated with increased rates of deep infection

BACKGROUND

Metabolic syndrome (MetS) is an abnormal physiological condition that has been increasingly identified as a risk factor for complications after orthopedic surgery. Given the lack of information on the effect of MetS in shoulder arthroplasty (SA), this investigation analyzed the rates of postoperative complications and implant survivorship free from reoperation and revision in patients with and without MetS.

METHODS

Between 2007 and 2017, data from 4635 adults who underwent a primary SA were collected and classified based on the presence or absence of MetS. MetS was defined as the existence of type 2 diabetes mellitus and a minimum of 2 of the following diagnoses: hyperlipidemia, hypertension, and body mass index ≥ 30 kg/m² within 1 year of surgery. Of the 4635 arthroplasties, 714 were performed in patients with MetS (anatomic total shoulder arthroplasty [aTSA] in 289 and reverse shoulder arthroplasty [RSA] in 425) and 3921 were performed in patients without MetS (aTSA in 1736 and RSA in 2185). Demographic characteristics, complications, reoperations, and revision surgery were compared.

RESULTS

At a mean of follow-up of 4.5 ± 2.3 years, 67 MetS patients (9.4%) and 343 non-MetS patients (8.7%) had sustained at least 1 postoperative complication (P = .851). Rotator cuff failure was the most common complication overall, with 84 cases (1.8%) (15 MetS cases [2.1%] and 69 non-MetS cases [1.8%], P = .851), and in both MetS and non-MetS patients, followed by infection, with 68 cases (1.2%) (10 MetS cases [1.4%] and 58 non-MetS cases [1.2%], P = .913). For aTSAs, the most common complication was rotator cuff failure (84 shoulders, 1.8%); for RSAs, the most common complication was periprosthetic fracture (52 shoulders, 1.1%). In RSAs, the rates of deep infection (1.9% vs. 0.7%, P = .04), instability (3.1% vs. 1.5%, P = .04), and deep venous thrombosis or pulmonary embolism (0.5% vs. 0.3%, P = .03) were found to be significantly higher in patients with MetS than in those without MetS. Reoperations were observed in 36 MetS patients (5%) and 170 non-MetS patients (4.3%) (P = .4). Revisions were performed in 30 MetS patients (4.2%) and 127 non-MetS patients (3.2%) (P = .19). The Kaplan-Meier 5-year rate of survivorship free from reoperation, revision, and prosthetic joint infection was equal between groups.

CONCLUSIONS

A preoperative diagnosis of MetS in patients undergoing primary SA did not significantly increase the risk of postoperative complications, infection, reoperation, or revision following primary SA. However, in the RSA subgroup, complications were significantly more common in patients with MetS. Individual risk factors may be more appropriate than the umbrella diagnosis of MetS prior to aTSA.

Shoulder Hemiarthroplasty with Nonprosthetic Glenoid Arthroplasty: The Ream-and-Run Procedure

»

Glenoid component wear and loosening are the principal failure modes of anatomic total shoulder arthroplasty (aTSA).

»

The ream-and-run (RnR) procedure is an alternative glenohumeral arthroplasty for patients who wish to avoid the risks and limitations of a prosthetic glenoid component.

»

During the RnR procedure, the arthritic glenoid is conservatively reamed to a single concavity, while the prosthetic humeral component and soft tissues are balanced to provide both mobility and stability of the joint.

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The success of the RnR procedure depends on careful patient selection, preoperative education and engagement, optimal surgical technique, targeted rehabilitation, and close postoperative communication between the surgeon and the patient.

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While the RnR procedure allows high levels of shoulder function in most patients, the recovery can be longer and more arduous than with aTSA.

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Patients who have undergone an RnR procedure occasionally require a second closed or open procedure to address refractory shoulder stiffness, infection, or persistent glenoid-sided pain. These second procedures are more common after the RnR than with aTSA.

Short-Term Outcomes After Total Shoulder Arthroplasty in Octogenarians: A Matched Analysis

Introduction

Studies have shown that the use of total shoulder arthroplasty is increasing every year in the United Stated at a rate higher than that of total hip or total knee arthroplasty. As the population of the United States continues to age, it is becoming more important for surgeons to understand the true impact of age on outcomes and complications following procedures such a total shoulder arthroplasty. The purpose of this study was to determine if octogenarians have poorer outcomes after total shoulder arthroplasty compared to a younger, matched control group.

Methods

Data was obtained through the American College of Surgeons National Surgical Quality Improvement Program database (ACS NSQIP). Patients who had undergone total shoulder arthroplasty were identified by Current Procedural Terminology code (23472). Indication for arthroplasty was determined by ICD9/10 code (osteoarthritis, fracture, other). Each octogenarian was matched 1:1 to a non-octogenarian based on sex, BMI, ASA class, medical comorbidities, functional status, and surgical indication for arthroplasty by propensity scoring. A subgroup analysis was performed to compare outcomes between only those patients who underwent TSA for osteoarthritis.Outcomes of interest were assessed between the two groups for statistical significance using a chi-squared test or fisher exact test for expected values of less than 5. Statistical significance was set at p<0.05.

Results

After matching, octogenarians were found to be at higher risk of readmission (4.7% vs. 3.3%, p=0.046), non-home discharge (27.1% vs. 9.4%, p<0.001), and overall surgical (4.4% vs. 2.5%, p=0.006) and medical complications (3.7% vs. 2.4%, p=0.039). In the setting of TSA for osteoarthritis only, however, octogenarians were only at higher risk for non-home discharge (22.4% vs. 7.5%, p<0.001).

Conclusions

Octogenarians are at higher risk of some complications following total shoulder arthroplasty but fewer than has been previously reported, particularly in the setting of arthroplasty for the treatment of arthritis.

Comparing Relative Value Units among Shoulder Arthroplasty, Hemiarthroplasty, and ORIF for Proximal Humerus Fractures in the Elderly: Which is Most Worth Your Time?

Background

Relative value units (RVUs) are assigned to Current Procedural Technology (CPT) codes and give relative economic values to the services physicians provide. This study compared the RVU reimbursements for the surgical options of proximal humerus fractures in the elderly, which include arthroplasty (reverse [RSA] and total [TSA]), hemiarthroplasty (HA), and open reduction and internal fixation (ORIF).

Methods

Using the National Surgical Quality Improvement Program, a total of 1,437 patients of at least 65 years of age with proximal humerus fractures between 2008 and 2016 were identified. Of those, 259 underwent RSA/TSA (CPT code 23472), 418 underwent HA (CPT codes 23470 and 23616), and 760 underwent ORIF (CPT code 23615). Univariate analysis compared RVU per minute, reimbursement rate, and the average annual revenue across cohorts based on respective operative times.

Results

RSA/TSA generated a mean RVU per minute of 0.197 (SD 0.078; 95%CI [0.188, 0.207]), which was significantly greater than the mean RVU per minute for 23470 HA (0.156; SD 0.057; 95%CI [0.148, 0.163]), 23616 HA (0.166; SD 0.065; 95%CI [0.005, 0.156]), and ORIF (0.135; SD 0.048; 95%CI [0.132, 0.138]; P<0.001). This converted to respective reimbursement rates of $6.97/min (SD 2.78; 95%CI [6.63, 7.31]), $5.48/min (SD 2.05; 95%CI [5.22, 5.74]), $5.83/min (SD 2.28; 95%CI [5.49, 6.16]) and $4.74/min (SD 1.69; 95%CI [4.62, 4.87]). After extrapolation, respective average annual revenues were $580,386, $456,633, $475,077, and $395,608.

Conclusion

RSA/TSA provides significantly greater reimbursement rates compared to HA and ORIF. Orthopaedic surgeons can use this information to optimize daily procedural cost-effectiveness in their practices.

Bent or broken: analysis of set screw fracture in the TFNa implant

Objectives

To evaluate set screw fracture in the Trochanteric Femoral Nail Advanced implant (TFNa, Synthes, West Chester, PA) and to identify additional mechanisms of set screw failure in the TFNa.

Materials and methods

Patients who had experienced failure after open reduction and internal fixation (ORIF) with the TFNa were identified. TFNa implants were explanted and inspected following revision surgery. Medical device reports (MDRs) and manufacturer’s inspection reports describing similar failures for the TFNa in the United States Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE) database were also reviewed.

Results

Four set screw fractures that occurred at a level II trauma center were observed. Sixty-seven reported failures were identified in the MAUDE database for review. Twenty-eight failed implants were returned to the manufacturer for inspection with a published inspection report available for analysis. Set screw fractures can occur in the TFNa when the set screw is deployed prematurely into the proximal screw aperture prior to blade/screw insertion. The set screw can also bend and deform if it is advanced against a helical blade/lag screw that is not fully seated into position, thereby potentially compromising its function.

Conclusion

The TFNa set screw allows for potential fracture during implant insertion leading to uncontrolled collapse, early excessive proximal femoral shortening, and rotational instability of the helical blade/lag screw. Similar failures in the TFNa can be prevented by having the surgeon inspect the proximal screw aperture after attachment of the proximal aiming aim to ensure the set screw has not been deployed prematurely.

Level of evidence

Therapeutic Level III.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10195-021-00594-8.

Complications After Anatomic Shoulder Arthroplasty: Revisiting Leading Causes of Failure

For practicing shoulder arthroplasty surgeons, it is advisable to consider a breadth of data sources concerning complications and outcomes. Although published series from high-volume centers are the primary source of data, these results may not be generalizable to a wide range of practice settings. National or health system-specific registry and medical device databases are useful adjuncts to assess the changing complication profile of shoulder arthroplasty, as well as to understand the complications specific to certain implants or implant types. To reduce the risk of postoperative complications, surgeons must have a clear understanding of the most common modes of failure.

Biomechanical comparison of zoned-conformity glenoid versus standard glenoid in total shoulder arthroplasty: impact on rotator cuff strain and glenohumeral translation

BACKGROUND

Current standard total shoulder arthroplasty glenoid implants allow for high levels of glenohumeral mismatch and associated high levels of humeral head translation to improve range of motion and reduce rim stresses on the glenoid. However, high levels of glenohumeral mismatch could also increase glenoid edge loading, eccentric wear, and rotator cuff strain. A zoned-conformity glenoid may be able to reduce the forces on the rotator cuff and glenoid. We compared rotator cuff strain and glenohumeral translation between a standard glenoid (SG) with moderate glenohumeral mismatch and a zoned-conformity glenoid (conforming glenoid [CG]) that limits mismatch. We hypothesized that the CG would have lower levels of strain on the rotator cuff and lower levels of humeral head translation compared with the SG.

METHODS

Eight fresh frozen cadaveric shoulders, aged 72 years (range, 67-76 years), were used in this biomechanical study. The specimens were first tested in the intact state. We cycled them 3 times from 0° to 60° of abduction and measured the superiorly-inferiorly and anteriorly-posteriorly directed forces at the joint, compressive forces applied to the glenoid, and humeral head translation. The specimens were then implanted with a standard press-fit humeral component and a polyethylene glenoid with 3 peripherally cemented pegs and a central press-fit peg. Testing was repeated. Finally, the SG was removed, the CG was implanted, and each specimen was tested a third time.

RESULTS

The average superiorly directed force at the glenohumeral joint was significantly lower in the intact and CG groups (18.1 ± 18.6 N and 19.8 ± 16.2 N, respectively) than in the SG group (29.3 ± 21.9 N, P = .024). The maximum force directed against the glenoid was also significantly lower in the CG group (87.6 ± 11.7 N) than in the SG (96.0 ± 7.3 N) and intact (98.9 ± 16.5 N) groups (P = .035). No difference was observed in humeral head translation in the anterior-posterior plane from 0° to 60° of abduction (P = .998) or in the superior-inferior plane (P = .999).

CONCLUSION

A zoned-conformity glenoid was associated with similar humeral head translation but significantly lower superior forces against the rotator cuff and a significantly lower maximum force against the glenoid compared with an SG implant. These biomechanical findings suggest that a zoned-conformity implant warrants further study in the effort to maintain humeral head translation while reducing rotator cuff and glenoid forces for successful outcomes of total shoulder arthroplasty.

Incidence of peripheral nerve injury in revision total shoulder arthroplasty: an intraoperative nerve monitoring study

BACKGROUND

The incidence of nerve injuries in revision total shoulder arthroplasty (TSA) is not well defined in the literature and may be higher than that in primary procedures, with 1 study reporting a complication rate of 50% for shoulder revisions. Given that continuous intraoperative nerve monitoring (IONM) can be an effective tool in diagnosing evolving neurologic dysfunction and preventing postoperative injuries, the purpose of this study was to report on IONM data and nerve injury rates in a series of revision TSAs.

METHODS

A retrospective cohort review of consecutive patients who underwent revision TSA was performed from January 2016 to March 2020. Indications for revision included infection (n = 7); failed total arthroplasty and hemiarthroplasty secondary to pain, dysfunction, and/or loose components (n = 36); and periprosthetic fracture (n = 1). Of the shoulders, 32 underwent revision to a reverse TSA, 6 underwent revision to an anatomic TSA, and 6 underwent spacer placement. IONM data included transcranial electrical motor evoked potentials (MEPs), somatosensory evoked potentials, and free-run electromyography. The motor alert threshold was set at ≥80% signal attenuation in any peripheral nerve. Patients were screened for neurologic deficits immediately following surgery, prior to administration of an interscalene nerve block, and during the first 2 postoperative visits. Additional data collection included surgical indication, sex, laterality, age at surgery, procedure performed, body mass index, history of tobacco use, Charlson Comorbidity Index, medical history, and preoperative range of motion.

RESULTS

A total of 44 shoulders in 38 patients were included, with a mean age of 63.2 years (standard deviation, 13.0 years). Of the procedures, 22.4% (n = 10) had an MEP alert, with 8 isolated to a single nerve (7 axillary and 1 radial) and 1 isolated to the axillary and musculocutaneous nerves. Only 1 patient experienced a major brachial plexus alert involving axillary, musculocutaneous, radial, ulnar, and median nerve MEP alerts, as well as ulnar and median nerve somatosensory evoked potential alerts. Age, sex, body mass index, Charlson Comorbidity Index, and preoperative range of motion were not found to be significantly different between cases in which an MEP alert occurred and cases with no MEP alerts. In the postoperative period, no minor or major nerve injuries were found whereas distal peripheral neuropathy developed in 4 patients (9.1%).

CONCLUSION

Among 44 surgical procedures, no patients (0%) had a major or minor nerve injury postoperatively and 4 patients (9.1%) complained of distal peripheral neuropathy postoperatively. In this study, we have shown that through the use of IONM, the rate of minor and major nerve injuries can be minimized in revision shoulder arthroplasty.

Adverse events involving hallux metatarsophalangeal joint implants: Analysis of the United States Food and Drug Administration data from 2010 to 2018

BACKGROUND

The prevalence of osteoarthritis of the hallux metatarsophalangeal joint (MTPJ) is 1 in 40 people over the age of 50. Surgical treatment options for MTPJ arthritis include joint preservation, joint resurfacing, and arthrodesis. Hallux MTPJ implants have evolved over the past several decades, but are associated with various complications. The aim of this study was to examine the MAUDE database to determine reported adverse events for hallux MTPJ implants.

MATERIALS AND METHODS

The US Food and Drug Administration's (FDA) Manufacturer and User Facility Device Experience (MAUDE) database was reviewed from 2010 to 2018 to review voluntary reported adverse event reports for approved implants within the United States. We recorded the type of adverse event and excluded duplicate reports and those extracted from already published literature.

RESULTS

Among 64 reported hallux MTPJ implant adverse events, the most common modes of adverse events were component loosening (34%), infection (14.1%), component fracture (9.4%), inflammation (9.4%), and allergic reaction (7.8%). Regarding implant type, Cartiva SCI had the highest percentage of adverse events (23.4%), followed by Arthrosurface ToeMotion (20.3%), Ascension MGT (12.5%), Arthrosurface HemiCAP® (10.9%), Futura primus (9.4%), and Osteomed Reflexion (6.3%). There was an increase in reported adverse events after 2016. The MAUDE database does not report the total incidence of implant insertion.

CONCLUSION

Our study of the MAUDE database demonstrated that component loosening and infection are the most common modes of adverse events for hallux MTPJ implants. Cartiva accounted for one-fourth of the implant-related adverse events during our study period, followed by ToeMotion, and Ascension MGT implants. Continued reporting of adverse events will improve our understanding on short and long-term complications of various hallux MTPJ implants.

LEVEL OF EVIDENCE

Level IV; Case Series from Large Database Analysis; Treatment Study.

Prevention and Treatment of Nerve Injuries in Shoulder Arthroplasty

➤

Nerve injuries during shoulder arthroplasty have traditionally been considered rare events, but recent electrodiagnostic studies have shown that intraoperative nerve trauma is relatively common.

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The brachial plexus and axillary and suprascapular nerves are the most commonly injured neurologic structures, with the radial and musculocutaneous nerves being less common sites of injury.

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Specific measures taken during the surgical approach, component implantation, and revision surgery may help to prevent direct nerve injury. Intraoperative positioning maneuvers and arm lengthening warrant consideration to minimize indirect injuries.

➤

Suspected nerve injuries should be investigated with electromyography preferably at 6 weeks and no later than 3 months postoperatively, allowing for primary reconstruction within 3 to 6 months of injury when indicated. Primary reconstructive options include neurolysis, direct nerve repair, nerve grafting, and nerve transfers.

➤

Secondary reconstruction is preferred for injuries presenting >12 months after surgery. Secondary reconstructive options with favorable outcomes include tendon transfers and free functioning muscle transfers.

Assessing the Value to the Patient of New Technologies in Anatomic Total Shoulder Arthroplasty

BACKGROUND

Publications regarding anatomic total shoulder arthroplasty (TSA) have consistently reported that they provide significant improvement for patients with glenohumeral arthritis. New TSA technologies that have been introduced with the goal of further improving these outcomes include preoperative computed tomography (CT) scans, 3-dimensional preoperative planning, patient-specific instrumentation, stemless and short-stemmed humeral components, as well as metal-backed, hybrid, and augmented glenoid components. The benefit of these new technologies in terms of patient-reported outcomes is unknown.

METHODS

We reviewed 114 articles presenting preoperative and postoperative values for commonly used patient-reported metrics. The results were analyzed to determine whether patient outcomes have improved over the 20 years during which new technologies became available.

RESULTS

The analysis did not identify evidence that the results of TSA were statistically or clinically improved over the 2 decades of study or that any of the individual technologies were associated with significant improvement in patient outcomes.

CONCLUSIONS

Additional research is required to document the clinical value of these new technologies to patients with glenohumeral arthritis.

LEVEL OF EVIDENCE

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