Complications of Shoulder Arthroplasty

Risk of revision based on timing of corticosteroid injection prior to shoulder arthroplasty

AIMS

Corticosteroid injections are often used to manage glenohumeral arthritis in patients who may be candidates for future total shoulder arthroplasty (TSA) or reverse shoulder arthroplasty (rTSA). In the conservative management of these patients, corticosteroid injections are often provided for symptomatic relief. The purpose of this study was to determine if the timing of corticosteroid injections prior to TSA or rTSA is associated with changes in rates of revision and periprosthetic joint infection (PJI) following these procedures.

METHODS

Data were collected from a national insurance database from January 2006 to December 2017. Patients who underwent shoulder corticosteroid injection within one year prior to ipsilateral TSA or rTSA were identified and stratified into the following cohorts: < three months, three to six months, six to nine months, and nine to 12 months from time of corticosteroid injection to TSA or rTSA. A control cohort with no corticosteroid injection within one year prior to TSA or rTSA was used for comparison. Univariate and multivariate analyses were conducted to determine the association between specific time intervals and outcomes.

RESULTS

In total, 4,252 patients were included in this study. Among those, 1,632 patients (38.4%) received corticosteroid injection(s) within one year prior to TSA or rTSA and 2,620 patients (61.6%) did not. On multivariate analysis, patients who received corticosteroid injection < three months prior to TSA or rTSA were at significantly increased risk for revision (odds ratio (OR) 2.61 (95% confidence interval (CI) 1.77 to 3.28); p < 0.001) when compared with the control cohort. However, there was no significant increase in revision risk for all other timing interval cohorts. Notably, Charlson Comorbidity Index ≥ 3 was a significant independent risk factor for all-cause revision (OR 4.00 (95% CI 1.40 to 8.92); p = 0.036).

CONCLUSION

There is a time-dependent relationship between the preoperative timing of corticosteroid injection and the incidence of all-cause revision surgery following TSA or rTSA. This analysis suggests that an interval of at least three months should be maintained between corticosteroid injection and TSA or rTSA to minimize risks of subsequent revision surgery. Cite this article: Bone Joint J 2022;104-B(5):620-626.

Initiation Timing of Continuous Interscalene Brachial Plexus Blocks in Patients Undergoing Shoulder Arthroplasty: A Retrospective Before-and-After Study

A continuous interscalene brachial plexus block (CIBPB) is usually administered before surgery in awake patients. However, the use of CIBPB before surgery could hinder the identification of nerve injuries after total shoulder arthroplasty (TSA). This study aimed to compare the analgesic effects of preoperatively and postoperatively initiated CIBPBs in patients undergoing TSA. The medical records of patients who underwent TSA between January 2016 and August 2020 were retrospectively reviewed. The following analgesic phases were used: intravenous (IV) patient-controlled analgesia (PCA) phase (IV PCA group, n = 40), preoperative block phase (PreBlock group, n = 44), and postoperative block phase (PostBlock group, n = 33). The postoperative initiation of CIBPB after a neurologic exam provided better analgesia than IV PCA and had no differences with the preoperative initiation of CIBPB, except for the worst pain at the postanesthetic care unit. Opioid consumption was significantly greater in the IV PCA group, but there were no differences between the PreBlock and PostBlock groups on operation day after the transfer to the general ward. The initiation of CIBPB after a patient’s emergence from general anesthesia had comparable analgesic efficacy with preoperative CIBPB but offered the chance of a postoperative neurologic exam.

Clindamycin Efficacy for Cutibacterium acnes Shoulder Device-Related Infections

Clindamycin is an antibiotic with high bioavailability and appropriate bone diffusion, often proposed as an alternative in guidelines for C. acnes prosthetic joint infections. We aimed to evaluate the efficacy of clindamycin in the treatment of C. acnes shoulder implant joint infections (SIJI). Methods: A retrospective analysis was conducted at the University Hospital of Nice (France) between 2010 and 2019. We included patients with one shoulder implant surgical procedure and at least one C. acnes positive sample. We selected the C. acnes SIJI according to French and international recommendations. The primary endpoint was favorable outcome of C. acnes SIJI treatment after at least 1-year follow-up in the clindamycin group compared to another therapeutic group. Results: Forty-eight SIJI were identified and 33 were treated with clindamycin, among which 25 were treated with monotherapy. The median duration of clindamycin antibiotherapy was 6 weeks. The average follow-up was 45 months; one patient was lost to follow-up. Twenty-seven patients out of 33 (82%) were cured with clindamycin, compared to 9/12 (75%) with other antibiotics. The rate of favorable outcomes increased to 27/31 (87%) with clindamycin and to 9/10 (90%) for other antibiotics when no septic revision strategies were excluded (P = 1.00). Conclusions: The therapeutic strategy based on one- or two-stage revision associated with 6 weeks of clindamycin seems to be effective.

Elongation of the brachial plexus after reverse shoulder arthroplasty: an anatomical study

INTRODUCTION

The use of reverse shoulder arthroplasty (RSA) is becoming more extended and its clinical results are good or excellent according to the literature. The main biomechanical characteristic of RSA is that it lowers and medializes the centre of rotation of the shoulder causing an arm lengthening. Although the number of neurological complications is low (5%), there are more neurophysiological changes in the brachial plexus with RSA than with the anatomic shoulder arthroplasty. The main goal of this study was to quantify the lengthening of the terminal branches of the brachial plexus suffered after RSA implantation.

MATERIALS AND METHODS

20 Embalmed cadavers were analysed. Four distances using bone references were employed to measure the lengthening of the arm and subacromial space. The brachial plexus and its terminal branches (radial, axillary, ulnar, musculocutaneous and median nerves) and the axillary artery, were identified and marked. Measurements were made to determine the change of position of the neurovascular structures, the arm lengthening and the lengthening of each nerve before and after the implantation of RSA. Two models of RSA were used: SMR^®(Lima) and Delta Xtend^®(DePuy-Synthes).

RESULTS

The mean arm elongation was 10.5 mm. The subacromial space suffers an elongation of 20.5-29.8%. All the neurovascular structures suffered elongation: median nerve 23.1%, musculocutaneous nerve 22.1%, ulnar nerve 19%, radial nerve 17%, axillary nerve 12-14.5%, axillary artery 24.8%. There were no differences in the results between the types of prosthesis.

CONCLUSIONS

Due to its design, the RSA causes an arm lengthening which is reflected by the elongation of the neurovascular structures of the arm.

Long-term results of the uncemented resurfacing shoulder hemiarthroplasty (Global Conservative Anatomic Prosthesis)

BACKGROUND

Treatment with uncemented resurfacing shoulder hemiarthroplasty has proved to be viable for patients with end-stage osteoarthritis at short- and mid-term follow-up. This study was essential to determine whether those outcomes will endure. This study presents the long-term results of the Global Conservative Anatomic Prosthesis (CAP) uncemented resurfacing shoulder hemiarthroplasty (DePuy Synthes, Warsaw, IN, USA).

METHODS

All patients with a diagnosis of glenohumeral osteoarthritis and an intact and clinically sufficient rotator cuff who underwent uncemented resurfacing shoulder hemiarthroplasty between 2007 and 2009 were included. The data of all patients who completed the 10-year follow-up assessments were used for analysis. The visual analog scale pain score, Dutch version of the Simple Shoulder Test score, Constant score, Short Form 12 scores, and physical examination findings were evaluated preoperatively and postoperatively on an annual basis. All complications and revisions were documented. Radiographs were evaluated for loosening, luxation or subluxation, migration, and glenoid erosion.

RESULTS

Of 48 shoulders, 23 (48%, 18 women and 5 men) were available for the 10-year follow-up assessments and their data were used for analysis. The main reasons for dropout were revision (27%) and death (10%). The mean follow-up period of the remaining patients was 10.9 years (range, 9-13 years). The visual analog scale pain score (from 6.5 ± 2.1 to 0.7 ± 1.6, P < .001), Simple Shoulder Test (Dutch version) score (from 22% ± 22% to 79% ± 22%, P < .001), Constant score (from 40 ± 29 to 70 ± 8, P < .001), and Short Form 12 physical score (from 36 ± 7 to 41 ± 12, P = .001) improved significantly compared with preoperative scores. Revision surgery was performed in 13 of the initial 48 shoulders (27%). Most revisions were seen within 7 years postoperatively.

CONCLUSION

Two revisions have been performed in the mid-term to long term because of increased functional outcome scores and the absence of signs of loosening. Nevertheless, the high overall revision rate of 27% between short- and long-term follow-up reflects the need to limit the use of uncemented resurfacing shoulder hemiarthroplasty for the treatment of glenohumeral osteoarthritis.

[3D printing in the field of shoulder surgery]

The 3D printing technology is a relatively new procedure with a high potential, especially in the field of shoulder surgery. The 3D printing procedures are increasingly being developed and also gaining new users. Principally, 3D printing procedures can be applied preoperatively in planning the surgical procedure, patient clarification and in teaching; however, the technology is increasing being used intraoperatively. In addition to intraoperative visualization of the models, 3D printing permits the use of individual and specific instruments and implants. This allows the precise transfer of the preoperative planning to the surgical procedure. Inaccuracies are mainly caused by soft tissues. The 3D printing can be beneficial in the fields of arthroplasty, shoulder instability as well as orthopedic trauma. The literature shows promising results in relation to duration of surgery, blood loss and clinical results of the procedure. On the other hand, it is still unclear which indications warrant the use of 3D printing. Other aspects that raise questions are the time of planning, the production time and the additional cost that the use of 3D printing entails. Nonetheless, 3D printing represents a meaningful enhancement of the portfolio of surgeons, which becomes highly beneficial and useful in complex situations. Furthermore, this procedure enables a certain amount of flexibility when reacting to certain circumstances.

Complications and further surgery after reverse total shoulder arthroplasty : report of 854 primary cases

AIMS

The aim of this study was to report the incidence of implant-related complications, further operations, and their influence on the outcome in a series of patients who underwent primary reverse total shoulder arthroplasty (RTSA).

METHODS

The prospectively collected clinical and radiological data of 797 patients who underwent 854 primary RTSAs between January 2005 and August 2018 were analyzed. The hypothesis was that the presence of complications would adversely affect the outcome. Further procedures were defined as all necessary operations, including reoperations without change of components, and partial or total revisions. The clinical outcome was evaluated using the absolute and relative Constant Scores (aCS, rCS), the Subjective Shoulder Value (SSV) scores, range of motion, and pain.

RESULTS

The overall surgical site complication rate was 22% (188 complications) in 152 patients (156 RTSAs; 18%) at a mean follow-up of 46 months (0 to 169). The most common complications were acromial fracture (in 44 patients, 45 RTSAs; 5.3%), glenoid loosening (in 37 patients, 37 RTSAs; 4.3%), instability (in 23 patients, 23 RTSAs; 2.7%), humeral fracture or loosening of the humeral component (in 21 patients, 21 RTSAs; 2.5%), and periprosthetic infection (in 14 patients, 14 RTSAs; 1.6%). Further surgery was undertaken in 79 patients (82 RTSAs) requiring a total of 135 procedures (41% revision rate). The most common indications for further surgery were glenoid-related complications (in 23 patients, 23 RTSAs; 2.7%), instability (in 15 patients, 15 RTSAs; 1.8%), acromial fractures (in 11 patients, 11 RTSAs; 1.3%), pain and severe scarring (in 13 patients, 13 RTSAs; 1.5%), and infection (in 8 patients, 8 RTSAs; 0.9%). Patients who had a complication had significantly worse mean rCS scores (57% (SD 24%) vs 81% (SD 16%)) and SSV scores (53% (SD 27%) vs 80% (SD 20%)) compared with those without a complication. If revision surgery was necessary, the outcome was even further compromised (mean rCS score: 51% (SD 23%) vs 63% (SD 23%); SSV score: 4% (SD 25%) vs 61% (SD 27%).

CONCLUSION

Although the indications for, and use of, a RTSA are increasing, it remains a demanding surgical procedure. We found that about one in five patients had a complication and one in ten required further surgery. Both adversely affected the outcome. Cite this article: Bone Joint J 2022;104-B(3):401-407.

Marking Pen Bacterial Contamination During Shoulder Surgery

Background:

Equipment used to guide surgical incisions has been shown to be a source of bacterial contamination during surgery.

Purpose/Hypothesis:

To compare the culture-positive rates of sterile marking pens used before and after skin preparation for shoulder surgery. It was hypothesized that there will be no difference in culture-positive rates from marking pens used after skin preparation compared with before skin preparation.

Study Design:

Controlled laboratory study.

Methods:

Overall, 43 consecutive patients undergoing elective shoulder surgery were enrolled prospectively into this study. Each patient provided 2 samples: study pens (from marking the surgical site incision after skin preparation) and positive control pens (from marking the surgical site incision before skin preparation). In addition, there were 43 negative control pens evaluated (straight from the packaging without any patient contact). Cultures were evaluated at 4 and 21 days, and all positive cultures were further evaluated for speciation, if able. Standard descriptive summaries and Fisher exact tests were used to compare the study samples.

Results:

The average age of the 43 patients was 54 years (range, 18-76 years). There were 29 (67%) female patients, and 30 (70%) procedures were on the right shoulder. Of the 43 procedures performed, 29 (67.4%) were arthroscopic, 12 (27.9%) were open, and 2 (4.7%) were closed. Of the 43 study pens, 1 culture was positive for Propionibacterium acnes (2.3%). Of the 43 positive control pens, 2 cultures were positive for bacterial growth (4.7%): P. acnes and Gram-positive bacilli (no speciation could be obtained). Of the 43 negative control pens, none of the cultures were positive for bacterial growth (0%). There was no statistical difference in the culture-positive rate between the study pens and the positive or negative control pens (P ≥ .999).

Conclusion:

Study results indicated that sterile surgical marking pens used to plan incisions and to outline anatomic landmarks did not have a higher culture-positive rate compared with pens used on unprepared skin or pens straight from the packaging.

Clinical Relevance:

As a precaution, sterile surgical marking pens should be discarded after use on the skin surface and not placed on the sterile field.

Mimicking the Composition and Structure of the Osteochondral Tissue to Fabricate a Heterogeneous Three-Layer Scaffold for the Repair of Osteochondral Defects

Heterogeneous three-layer scaffolds were fabricated by mimicking the biochemical composition and structure of the hyaline cartilage, calcified cartilage, and subchondral bone of the osteochondral tissue for the repair of osteochondral defects. The hyaline cartilage layer was composed of collagen I (50.0 wt %) and sodium hyaluronate (50.0 wt %). The calcified cartilage layer and subchondral bone layer were composed of collagen I, sodium hyaluronate, and nanohydroxyapatite with different proportions. N-Hydroxysuccinimide/N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride was used to mediate the crosslinking reaction of the amine groups of collagen with carboxyl groups of sodium hyaluronate. The hyaline cartilage layer and calcified cartilage layer were designed as dense structures, while the subchondral bone layer was designed as a relatively loose structure by adjusting the crosslinking degree. The scaffolds displayed a uniform and interconnected porous structure and possessed a high porosity over 85%, which were conducive to cellular adhesion and proliferation. The scaffolds could remain at 50-75% after 30 days of degradation owing to crosslinking, providing enough time for the regeneration of the osteochondral tissue. Especially, the hyaline cartilage layer and calcified cartilage layer preferred to induce the proliferation of chondrocytes, while the subchondral bone layer was more conducive to the proliferation of osteoblasts. In conclusion, the heterogeneous multilayer scaffolds could serve as implant materials for osteochondral reconstruction.

Is reverse total shoulder arthroplasty (rTSA) more advantageous than anatomic TSA (aTSA) for osteoarthritis with intact cuff tendon? A systematic review and meta-analysis

PURPOSE

We aimed to compare the outcomes and complications of anatomical shoulder arthroplasty (aTSA) and reverse total shoulder arthroplasty (rTSA) for primary glenohumeral osteoarthritis with intact cuff tissue.

MATERIALS AND METHODS

The MEDLINE, Embase, and Cochrane Library databases were systematically searched for studies published before March 2, 2021 using the PRISMA guidelines. Studies were included if they directly compared aTSA and rTSA for treating primary glenohumeral arthritis. A meta-analysis was performed using six studies that compared radiologic outcomes, functional scores, and range of motion (ROM). All the data were pooled using a random-effects model. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated as dichotomous data, while continuous data were analyzed using mean differences with 95% CIs.

RESULTS

Two independent researchers reviewed 1,061 studies. Six studies met the inclusion criteria. The range of motion, especially external rotation, was better for aTSA than for rTSA (MD = - 10.28, 95% CI: - 16.69 to - 3.88, P = 0.002). Functional scores showed no difference between aTSA and rTSA. Glenoid loosening (OR = 0.17, 95% CI: 0.06-0.50, P = 0.001) was more common with aTSA, and scapula notching (OR = 10.63, 95% CI: 1.73-65.27, P = 0.01) with rTSA. In the mid-term follow-up, the overall revision rate showed no difference between aTSA and rTSA, with a pooled OR of 0.33 (95% CI: 0.07-1.57, P = 0.16).

CONCLUSION

A better ROM was achieved after aTSA than after rTSA. There was no difference in the revision rate at mid-term follow-up between aTSA and rTSA. Glenoid loosening was more common with aTSA, and scapula notching with rTSA.

LEVEL OF EVIDENCE

Level IV, Meta-analysis.

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.

Defining a Synovial Fluid White Blood Cell Count Threshold to Predict Periprosthetic Infection after Shoulder Arthroplasty

BACKGROUND

The diagnosis of periprosthetic shoulder infection (PSI) requires a thorough diagnostic workup. Synovial fluid aspiration has been proven to be a reliable tool in the diagnosis of joint infections of the lower extremity, but shoulder specific data is limited. This study defines a threshold for synovial fluid white blood cell count (WBC) and assesses the reliability of microbiological cultures.

METHODS

Retrospective study of preoperative and intraoperative fluid aspiration of 31 patients who underwent a revision of a shoulder arthroplasty (15 with PSI defined by IDSA criteria, 16 without infection). The threshold for WBC was calculated by ROC/AUC analysis.

RESULTS

WBC was significantly higher in patients with PSI than in other patients. A threshold of 2800 leucocytes/mm3 showed a sensitivity of 87% and a specificity of 88% (AUROC 0.92). Microbiological cultures showed a sensitivity of 76% and a specificity of 100%.

CONCLUSIONS

A threshold of 2800 leucocytes/mm3 in synovial fluid can be recommended to predict PSI. Microbiological culture has an excellent specificity and allows for targeted antibiotic therapy. Joint aspiration presents an important pillar to diagnose PSI.

Complications and Intraoperative Fractures in Reverse Shoulder Arthroplasty: A Systematic Review

Introduction

The reverse shoulder arthroplasty is nowadays a treatment option for a variety of shoulder problems. As its incidence rose, also the number of complications increased, including intraoperative fractures.

Significance

We performed a systematic review and critical analysis of the current literature following the PRISMA guidelines. Our purpose was to: 1) determine incidence, causes, and characteristics of intraoperative fractures; 2) evaluate their current treatment options, possible related complications, reoperation rates, and the patients’ outcome; and 3) determine the overall incidence of each complication related to reverse shoulder arthroplasty. The articles were selected from PubMed medical database in April 2020 using a comprehensive search strategy. Rayyan software was used to support the selection process of the records. A descriptive and critical analysis of the results was performed.

Results

The study group included a total of 13,513 reverse shoulder arthroplasty procedures. The total number of complications was 1647 (rate 12.1%). The most common complication was dislocation (340 cases, rate 2.5%). Forty-six studies reported a total of 188 intraoperative fractures among the complications (rate 1.4%). The intraoperative fracture rate was 2.9% and 13.6% in primary and revision settings, respectively. There were 136 humeral fractures, 60% of them occurred in revision RSAs, during the removal of the previous implant, and involved the shaft in the majority of cases (39%). Glenoid fractures were 51 and occurred mostly during the reaming of the glenoid. We observed 7 further related complications (rate of 4%) and 3 reoperations (rate of 1.5%). The outcome was satisfactory in the majority of cases.

Conclusions

A comprehensive review on intraoperative fractures in reverse shoulder arthroplasties is presented. Results suggest favorable outcomes for all treatment methods, with a modest further complication rate. This investigation may aid in the treatment decision-making for these complications.

Complications of Reverse Total Shoulder Arthroplasty: A Computational Modelling Perspective

Reverse total shoulder arthroplasty (RTSA) is an established treatment for elderly patients with irreparable rotator cuff tears, complex proximal humerus fractures, and revision arthroplasty; however, with the increasing indications for RTSA over the last decade and younger implant recipients, post-operative complications have become more frequent, which has driven advances in computational modeling and simulation of reverse shoulder biomechanics. The objective of this study was to provide a review of previously published studies that employed computational modeling to investigate complications associated with RTSA. Models and applications were reviewed and categorized into four possible complications that included scapular notching, component loosening, glenohumeral joint instability, and acromial and scapular spine fracture, all of which remain a common cause of significant functional impairment and revision surgery. The computational shoulder modeling studies reviewed were primarily used to investigate the effects of implant design, intraoperative component placement, and surgical technique on postoperative shoulder biomechanics after RTSA, with the findings ultimately used to elucidate and mitigate complications. The most significant challenge associated with the development of computational models is in the encapsulation of patient-specific anatomy and surgical planning. The findings of this review provide a basis for future direction in computational modeling of the reverse shoulder.

Intraoperative fractures in shoulder arthroplasty: risk factors and outcomes

Background

The incidence of shoulder arthroplasty in the United States continues to increase, and while the risk of intraoperative complications such as fracture remains relatively low, there has been little investigation into whether certain patient-specific risk factors predispose to this complication. This study characterizes the incidence of intraoperative fracture during shoulder arthroplasty and additionally hypothesizes that certain risk factors may exist in addition to potentially leading to worsened near-term outcomes.

Methods

An institutional database of shoulder arthroplasties (N = 1773; 994 anatomic, 779 reverse) was retrospectively reviewed, and the operative reports for each case were examined for documentation of an intraoperative fracture, including during which surgical step the fracture took place. Various preoperative and intraoperative factors were tested for comparative significance (P < .05) using chi-square and Kruskal-Wallis tests as appropriate. Length of stay, 90-day readmission, and discharge to rehabilitation or skilled nursing facility (SNF) were further examined as secondary outcomes.

Results

Twenty-one (1.2%) intraoperative fractures were documented, a majority of which occurred in reverse shoulder arthroplasties compared to anatomic procedures (overall incidence: 2.5% vs. 0.2%, P < .001). These most commonly occurred during either stem broaching (33%) or seating (33%) and were most likely to involve the metaphysis (53%) or greater tuberosity (33%). Five fractures occurred during revision arthroplasty, while 16 fractures occurred during primary procedures (overall incidence: 3.0 vs. 1.0%, P = .03). Patient factors reaching statistical significance included female gender and liver disease, while age and smoking history were notably not associated with intraoperative fracture. The fracture cohort had a significantly longer mean length of stay (2.42 vs. 2.17 days, P < .001). While the rates of 90-day readmission and discharge to SNF/rehab were higher in the fracture cohort, these values did not reach statistical significance.

Conclusion

Intraoperative fractures are a rare complication (1.2%) in shoulder arthroplasty, with reverse shoulder arthroplasty, revision cases, and female gender associated with an elevated overall risk. While these patients had a longer inpatient hospitalization, the substantially higher rates of 90-day readmission and discharge to SNF/rehab did not reach significance in our limited institutional cohort. The aforementioned incidence and risk factors serve as crucial evidence for use during the preoperative counseling process with patients as part of a shared decision-making model.

Initial Assessments of a Handheld Indentation Probe's Correlation With Cancellous Bone Density, Stiffness, and Strength: An Objective Alternative to “Thumb Testing”

Objective: During shoulder arthroplasty, surgeons must select the optimal implant for each patient. The metaphyseal bone properties affect this decision; however, the typical resection “thumb test” lacks objectivity. This investigation's purposes were to determine the correlation strength between the indentation depth of a handheld mechanism and the density, compressive strength, and modulus of a bone surrogate; as well as to assess how changing the indenter tip shape and impact energy may affect the correlation strengths. Methods: A spring-loaded indenter was developed. Four tip shapes (needle, tapered, flat, and radiused cylinders) and four spring energies (0.13 J–0.76J) were assessed by indenting five cellular foam bone surrogates of varying density, every five times. After each indentation, the indentation depth was measured with a separate probe and correlated with manufacturer specifications of the apparent density, compressive strength, and modulus. Results: indentation depth plateaued as the bone surrogate's material properties increased, particularly for indentation tips with larger footprints and the 0.13 J spring. All tip shapes produced strong (R2≥0.7) power-law relationships between the indentation depth metric and the bone surrogate's material properties (density: 0.70 ≤ R2 ≤ 0.95, strength: 0.75 ≤ R2 ≤ 0.97, modulus: 0.70 ≤ R2 ≤ 0.93); though the use of the needle tip yielded the widest indentation depth scale. Interpretation: these strong correlations suggest that a handheld indenter may provide objective intra-operative evidence of cancellous material properties. Further investigations are warranted to study indenter tip shape and spring energy in human tissue; though the needle tip with spring energy between 0.30 J and 0.76 J seems the most promising.

A Long-Term Follow-Up of Post-Operative Periprosthetic Humeral Fracture in Shoulder Arthroplasty

Background

During the last decades, the growing number of shoulder replacement has increased the associated complications. Periprosthetic fractures have a low incidence but can be a severe clinical condition, especially in elderly population. There are still no guidelines to define the best treatment protocol for post-operative periprosthetic humeral fractures. Factors associated to these fractures and consequently the decision-making for the best treatment seem to be patient-related but also correlated with the type of implant. The aim of this study is to analyze the patient’s risk factors, fracture pattern, implant type and treatment, evaluating the outcome with a long-term follow-up.

Methods

A retrospective study was performed on more than 2700 shoulder prostheses implanted over 10 years in two specialized centers, identifying 19 patients who underwent surgery for post-operative periprosthetic fracture. Gender, age, comorbidities, type of prosthetic implant, type of fracture, and cortical index of each patient were evaluated. All patients underwent surgery and were evaluated with a mean follow-up of 5 years with radiographic controls and functional assessment with the Constant–Murley score.

Results

Complete healing was achieved in 18 of 19 patients. All patients presented a lower Constant–Murley score than the pre-fracture score, there were no significant differences between prosthetic implants, and the cortical index was lower than the threshold level in more than 60% of cases.

Conclusion

The results of this study showed that a correct preoperative planning is essential to evaluate the type of implant and possible signs of stem mobilization. With a stable stem, it is preferable to maintain it and proceed to a synthesis. The decision process is more complex in periprosthetic fractures with a reduced cortical index, when some radiolucency lines are present in stems with high primary stability, because it is not always indicative of an unstable stem.

Level of Evidence

Therapeutic III

Clinical and radiographic outcomes of total shoulder arthroplasty with a partially cemented all-polyethylene pegged bone-ingrowth glenoid component: a systematic review

BACKGROUND

Several articles have been published reporting on the clinical performance of a novel pegged, all-polyethylene glenoid component design which features a central peg, circumferentially fluted, interference-fit peg for tissue integration and three small peripheral pegs for cementing. However, no systematic review exists to this date.

METHODS

The US National Library of Medicine (PubMed/MEDLINE), EMBASE, and the Cochrane Database of Systematic Reviews were queried for publications up to May 2020.

RESULTS

Overall, 13 articles were included for analysis (560 operated shoulders, range of mean follow-up: 2-6 years). The survival rate was 98.2% (550 out of 560 cases), while the rate of aseptic loosening was 0.2% (1 out of 560 cases). There were 139 cases (out of 399 reported; 34.1%) with peri-glenoid radiolucency, and 35 cases (out of 223 reported; 15.7%) of asymptomatic central peg osteolysis, with 1 of them undergoing revision.

CONCLUSIONS

There was fair quality of evidence to show that partially cemented all-polyethylene pegged bone-ingrowth glenoid components produce promising results, with a low revision rate in the short- to medium-term follow-up. Nevertheless, this analysis showed high rates of both radiolucency of the glenoid component and osteolysis around the central peg which raise concern for potential failure of this glenoid component in the long-term follow-up.

LEVEL OF EVIDENCE

Systematic review, IV.

Anatomic versus reverse shoulder arthroplasty: a mid-term follow-up comparison

BACKGROUND

Anatomic total shoulder arthroplasty improves pain and function with a reported reoperation rate of approximately 1% per year. With improved glenoid fixation, reverse shoulder arthroplasty implants may outperform anatomic total shoulder arthroplasty. We evaluate the functional outcomes and reoperation rate of anatomic total shoulder arthroplasty versus reverse shoulder arthroplasty at a minimum eight-year follow-up or revision.

METHODS

Between 2005 and 2010, 187 shoulders (137 anatomic total shoulder arthroplasty, 50 reverse shoulder arthroplasty) were retrospectively reviewed at a mean of 8.8 years. The mean age at surgery was 67 years. Females were more commonly treated with reverse shoulder arthroplasty. Both groups had similar body mass index and comorbidities. Outcome measures evaluated included abduction, forward elevation, external rotation, internal rotation, Simple Shoulder Test, Constant score, American Shoulder and Elbow Score, University of California Los Angeles Shoulder score, and Shoulder Pain and Disability Index.

RESULTS

At follow-up, anatomic total shoulder arthroplasty demonstrated greater overhead range of motion and external rotation. All patient-reported outcomes remained similar between groups. Reverse shoulder arthroplasty patients were more likely to rate shoulders as much better or better after surgery (90% versus 67%, p = 0.004). Complications were observed in 24% of anatomic total shoulder arthroplasties and 8% of reverse shoulder arthroplasties (p = 0.02). Reoperation was more common in anatomic total shoulder arthroplasties (23% versus 4%, p = 0.003).

DISCUSSION

At mid-to-long-term follow-up, reverse shoulder arthroplasties demonstrated significantly fewer complications and reoperations than anatomic total shoulder arthroplasties. Despite similar patient-reported outcomes, reverse shoulder arthroplasty patients were more likely to be satisfied with their shoulder.

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.

Minimum five-year outcomes of reverse total shoulder arthroplasty using a trabecular metal glenoid base plate

AIMS

Reverse total shoulder arthroplasty (RTSA) using trabecular metal (TM)-backed glenoid implants has been introduced with the aim to increase implant survival. Only short-term reports on the outcomes of TM-RTSA have been published to date. We aim to present the seven-year survival of TM-backed glenoid implants along with minimum five-year clinical and radiological outcomes.

METHODS

All consecutive elective RTSAs performed at a single centre between November 2008 and October 2014 were reviewed. Patients who had primary TM-RTSA for rotator cuff arthropathy and osteoarthritis with deficient cuff were included. A total of 190 shoulders in 168 patients (41 male, 127 female) were identified for inclusion at a mean of 7.27 years (SD 1.4) from surgery. The primary outcome was survival of the implant with all-cause revision and aseptic glenoid loosening as endpoints. Secondary outcomes were clinical, radiological, and patient-related outcomes with a five-year minimum follow-up.

RESULTS

The implant was revised in ten shoulders (5.2%) with a median time to revision of 21.2 months (interquartile range (IQR) 9.9 to 41.8). The Kaplan-Meier survivorship estimate at seven years was 95.9% (95% confidence interval (CI) 91.7 to 98; 35 RTSAs at risk) for aseptic mechanical failure of the glenoid and 94.8% (95% CI 77.5 to 96.3; 35 RTSAs at risk) for all-cause revision. Minimum five-year clinical and radiological outcomes were available for 103 and 98 RTSAs respectively with a median follow-up time of six years (IQR 5.2 to 7.0). Median postoperative Oxford Shoulder Score was 38 (IQR 31 to 45); median Constant and Murley score was 60 (IQR 47.5 to 70); median forward flexion 115° (IQR 100° to 125°); median abduction 95° (IQR 80° to 120°); and external rotation 25° (IQR 15° to 40°) Scapular notching was seen in 62 RTSAs (63.2%).

CONCLUSION

We present the largest and longest-term series of TM-backed glenoid implants demonstrating 94.8% all-cause survivorship at seven years. Specifically pertaining to glenoid loosening, survival of the implant increased to 95.9%. In addition, we report satisfactory minimum five-year clinical and radiological outcomes. Cite this article: Bone Joint J 2021;103-B(8):1333-1338.

Surgical Complications After Reverse Total Shoulder Arthroplasty and Total Shoulder Arthroplasty in the United States

Shoulder arthroplasty has become popular in the treatment of degenerative shoulder conditions in the United States. Shoulder arthroplasty usage has expanded to younger patients with increased surgical indications.

Is suture cerclage fixation a valid treatment for intraoperative nondisplaced calcar fractures in reverse total shoulder arthroplasties?

Background

Implantation rates of reverse total shoulder arthroplasties continue to grow worldwide. Despite satisfying results, a distinct number of complications persist. Intraoperative fractures of the humeral shaft might occur in a certain number of cases. The literature is sparse regarding incidence and treatment options. This study analyzed the treatment using suture cerclage or stainless-steel-cable cerclage.

Methods

Our prospectively followed-up cohort of 860 patients who received primary reverse total shoulder arthroplasty in a tertiary referral hospital between September 2005 and August 2018 was screened for intraoperative medial humeral calcar fractures. The patients were retrospectively analyzed as per the treatment algorithm using (1) suture cerclage with FiberWire, (2) cable cerclage with stainless steel cable, or (3) no intervention. The outcome was radiologically and clinically (Subjective Shoulder Value and Constant score) evaluated.

Results

A total of 39 (4.5%) intraoperative calcar fractures of the humeral shaft were identified with 29 cases available for analysis at a mean follow-up time of 52 ± 27 months. Sixteen of them were treated with suture cerclage, 7 with metal cable cerclage, and 6 without intervention. All fractures were nondisplaced or could be reduced anatomically and healed without any stem subsidence or loosening within the first 4.5 months. The intervention groups reached similar values for the Subjective Shoulder Value (68%±27% vs. 79%±19%, suture vs. cable) and relative Constant score (65 % ± 25 % vs. 75 % ± 23).

Conclusion

Intraoperative medial calcar fractures can be sufficiently treated with metal or suture cerclage fixation. High-strength polyblend-polyethylene sutures seem to be a valid therapeutic option for selected medial calcar fractures of the humerus. In selected cases, however, benign neglect can result in excellent results as well.

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.

Regional apparent density correlations within the proximal humerus

Background

Bone quality influences humeral implant selection for shoulder arthroplasty. However, little is known about how well bone near the humeral resection represents more distal cancellous bone. This investigation aimed to quantify the correlations between the apparent density of sites near the humeral head resection plane and cancellous sites throughout the metaphysis.

Methods

Using computed tomography data from 98 subjects, apparent bone density was quantified in 65 regions throughout the proximal humerus. Pearson's correlation coefficient was determined comparing the density between samples from the humeral resection and all supporting regions beneath the resection. Mean correlation coefficients were compared for (i) each sample region with all support regions, (ii) pooling all sample regions within a slice, and (iii) considering sample regions correlated with only the support regions in the same anatomic section.

Results

Stronger correlations existed for bone sampled beneath the resection (0.33 ± 0.10≤ r ≤ 0.88 ± 0.10), instead of from the resected humeral head (0.22 ± 0.10≤ r ≤ 0.66 ± 0.14). None of sample region correlated strongly with all support regions; however, strong correlations existed when sample and support regions both came from the same anatomic section.

Discussion

Assessments of cancellous bone quality in the proximal humerus should be made beneath the humeral resection not in the resected humeral head; and each anatomic quadrant should be assessed independently.

Neurologic complications in primary anatomic and reverse total shoulder arthroplasty: A review

Neurologic injury during shoulder replacement is one of the less common complications of the procedure, however the clinical implications can be significant. The purpose of this paper is to review the current literature on neurologic complications in various types of shoulder replacement and provide recommendations regarding avoidance, evaluation, and management of these complications.

Role of pre-revision tissue biopsy in evaluation of painful shoulder arthroplasty: a systematic review and meta-analysis

BACKGROUND

Pre-revision tissue biopsy (PTB) for culture has been used as a diagnostic tool in the evaluation for periprosthetic joint infection among patients with a painful shoulder arthroplasty. The purpose of this study was to (1) determine the sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) of PTB culture results compared with results of "gold-standard" tissue biopsy for culture taken at the time of subsequent revision surgery (TBR), and (2) report the current indications and protocols described for use of PTB. The hypothesis was that PTB culture results would correlate highly with results of TBR and that protocols for PTB would vary by institution.

METHODS

By use of Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, a systematic review and meta-analysis of English-language literature were performed using the Embase, MEDLINE, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and Cochrane databases from inception through March 2020. Methodological Index for Non-randomized Studies (MINORS) validated grading criteria were used to summarize the quality and bias of included studies. Studies were included if an arthroscopic or open tissue biopsy was performed in patients who had previously undergone anatomic total shoulder arthroplasty, shoulder hemiarthroplasty, or reverse total shoulder arthroplasty as a separate procedure prior to revision of components, if applicable. Meta-analysis to identify the sensitivity, specificity, NPV, and PPV of PTB was performed. Analysis was performed by first defining 1 positive PTB culture result as infection and then defining 2 positive culture results as infection.

RESULTS

A total of 1751 titles were screened, and 66 full-text articles were reviewed for inclusion. Four total studies encompassing 72 cases met the inclusion criteria. All studies were small (N = 13 to N = 23), retrospective series, with all but 12 biopsies performed arthroscopically. Sixty-five patients (90.2%) underwent subsequent revision surgery and TBR. Of these patients, 23 (35.4%) had ≥1 positive culture result with PTB and TBR. By this definition, the sensitivity of PTB was 92.0% (95% confidence interval [CI], 72.5%-98.6%); specificity, 70.0% (95% CI, 53.3%-82.9%); PPV, 65.7% (95% CI, 47.7%-80.3%); and NPV, 93.3% (95% CI, 76.5%-98.8%). For 2 positive PTB results, the sensitivity of PTB was 100% (95% CI, 51.7%-100%); specificity, 50.0% (95% CI, 31.4%-68.6%); PPV, 33.3% (95% CI, 14.4%-58.8%); and NPV, 100% (95% CI, 69.9%-100%). No complications of PTB were reported. The mean Methodological Index for Non-randomized Studies (MINORS) grade was 11.4 (range, 8.5-14).

CONCLUSION

PTB is a sensitive diagnostic modality with a high NPV that may aid in the diagnosis of shoulder periprosthetic joint infection in patients with a painful shoulder arthroplasty. Given the disparate biopsy protocols, greater standardization of clinical best practices and broader prospective studies are necessary to define the future role of PTB in dictating treatment.

An analysis of the Oxford Shoulder Score and its relationship to early joint revision in the New Zealand Joint Registry

BACKGROUND

Primary shoulder arthroplasties significantly improve shoulder function and have acceptable prosthesis survival for various indications. Currently, no validated shoulder questionnaire exists that can anticipate the early failure of primary shoulder arthroplasties. This study hypothesized that the Oxford Shoulder Score (OSS) after primary shoulder arthroplasty at 6 months would be significantly associated with early revision procedures.

METHODS

Data on all primary and revision shoulder arthroplasties covering the period of January 1, 1999, to December 31, 2019, were obtained from the New Zealand Joint Registry. The OSS questionnaires at 6 months were analyzed with regard to their relationship to revision within 2 years from the questionnaire date. Confounding risk factors were adjusted for in multivariate logistic regression analysis.

RESULTS

Statistical analysis revealed that the 6-month OSS had a significant association with revision in the following 2 years for anatomic total shoulder arthroplasty (TSA), reverse total shoulder arthroplasty (RSA), and shoulder hemiarthroplasty (HA) (P < .001). An OSS of ≤44 for TSAs, ≤40 for RSAs, and ≤33 for HAs accounted for 68.9%, 63.1%, and 50.7%, respectively, while capturing at least 85% of revisions for all prostheses within the following 2 years.

CONCLUSION

This study confirms that a poor OSS at 6 months is an independent risk factor for early revision after TSA, RSA, and HA. We recommend discharging patients with a 6-month OSS greater than the identified threshold values for each prosthesis to improve resource efficiency.

Glenoid bony morphology of osteoarthritis prior to shoulder arthroplasty: what the surgeon wants to know and why

Shoulder arthroplasty is performed with increasing frequency, and osteoarthritis is the most common indication for this procedure. However, the glenoid side of the joint is widely recognized as a limiting factor in the long-term durability of shoulder replacement, and osteoarthritis leads to characteristic bony changes at the glenoid which can exacerbate this challenge by reducing the already limited glenoid bone stock, by altering biomechanics, and by interfering with operative exposure. This article reviews the Walch classification system for glenoid morphology. Several typical findings of osteoarthritis at the glenoid are discussed including central bone loss, posterior bone loss, retroversion, biconcavity, inclination, osteophyte formation, subchondral bone quality, and bone density. The three primary types of shoulder arthroplasty are reviewed, along with several techniques for addressing glenoid deformity, including eccentric reaming, bone grafting, and the use of augmented glenoid components. Ultimately, a primary objective at shoulder arthroplasty is to correct glenoid deformity while preserving bone stock, which depends critically on characterizing the glenoid at pre-operative imaging. Understanding the surgical techniques and the implications of glenoid morphology on surgical decision-making enables the radiologist to provide the morphologic information needed by the surgeon.

Chronic Kidney Disease Is Associated with High Mortality Risk in Patients with Diabetes after Primary Shoulder Arthroplasty: A Nationwide Population-Based Cohort Study

The number of diabetic patients with chronic kidney disease (CKD) undergoing shoulder arthroplasty is growing. This study aims to compare perioperative outcomes of shoulder arthroplasty in diabetic patients at different renal function stages. Between 1998 and 2013, a total of 4443 diabetic patients with shoulder arthroplasty were enrolled: 1174 (26%) had CKD without dialysis (CKD group), 427 (9%) underwent dialysis (dialysis group), and 3042 (68%) had no CKD (non-CKD group). Compared with the non-CKD group, the CKD (odds ratio [OR], 4.69; 95% confidence interval [CI], 2.02–10.89) and dialysis (OR, 6.71; 95% CI, 1.63–27.73) groups had a high risk of in-hospital death. The dialysis group had a high risk of infection after shoulder arthroplasty compared with the CKD (subdistribution hazard ratio [SHR], 1.69; 95% CI, 1.07–2.69) and non-CKD (SHR, 1.76; 95% CI, 1.14–2.73) groups. The dialysis group showed higher risks of all-cause readmission and mortality than the CKD and non-CKD groups after a 3-month follow-up. In conclusion, CKD was associated with worse outcomes after shoulder arthroplasty. Compared with those without CKD, CKD patients had significantly increased readmission and mortality risks but did not have an increased risk of surgical complications, including superficial infection or implant removal.

Comparison of complication types and rates associated with anatomic and reverse total shoulder arthroplasty

BACKGROUND

Complications after anatomic (aTSA) and reverse (rTSA) total shoulder arthroplasty can be devastating to a patient's quality of life and require revisions that are costly to both the patient and the health care system. The purpose of this study is to determine the types, incidence, and timing of complications following aTSA and rTSA using an international database of patients who received a single-platform total shoulder arthroplasty system, in order to quantify the types of failure modes and the differences that occur between aTSA and rTSA.

METHODS

A total of 2224 aTSA (male-female, 1090:1134) and 4158 rTSA (male-female, 1478:2680) patients were enrolled in an international database of primary shoulder arthroplasty performed by 40 different surgeons in the United States and Europe. Adverse events and revisions reported for these 6382 patients were analyzed to identify the most common failure modes associated for both aTSA and rTSA.

RESULTS

For the 2224 aTSA patients, 239 adverse events were reported for a complication rate of 10.7% and 124 revisions for a revision rate of 5.6%. The top 3 complications for aTSA were rotator cuff tear/subscapularis failure (n = 69; complication rate = 3.1%, revision rate = 1.9%), aseptic glenoid loosening (n = 55; complication rate = 2.5%, revision rate = 1.9%), and infection (n = 28; complication rate = 1.3%, revision rate = 0.8%). For the 4158 rTSA patients, 372 adverse events were reported for a complication rate of 8.9% and 104 revisions for a revision rate of 2.5%. The top 3 complications for rTSA were acromial/scapular fracture/pain (n = 102; complication rate = 2.5%, revision rate = 0.0%), instability (n = 60; complication rate = 1.4%, revision rate = 1.0%), and pain (n = 49; complication rate = 1.2%, revision rate = 0.2%).

CONCLUSIONS

This large database analysis quantified complication and revision rates for aTSA and rTSA. We found aTSA and rTSA complication rates of 10.7% and 8.9%, respectively; with revision surgery rates of 5.6% and 2.5%, respectively. The 2 most common complications for each prosthesis type (aTSA: subscapularis/rotator cuff tears, aseptic glenoid loosening; rTSA: acromial/scapular fractures, instability) were unique to each device. The rate of infection was similar for both. Future prosthesis and technique development should work to mitigate these common complication types in order to reduce their rate of occurrence.

Increasing severity of anemia is associated with poorer 30-day outcomes for total shoulder arthroplasty

Background

Total shoulder arthroplasty (TSA) has increased in utilization over the past several decades. Anemia is a common preoperative condition among patients undergoing TSA and has been associated with poorer outcomes in other surgical procedures. To the best of our knowledge, no study has analyzed the association between anemia severity and TSA outcomes. Therefore, the purpose of this study is to determine the effects that increasing severity of anemia may have on the postoperative outcomes in patients receiving primary TSA.

Methods

A retrospective analysis was performed using the American College of Surgeons National Surgery Quality Improvement Project database from the years 2015 to 2018. Current Procedure Terminology code 23472 was used to identify all primary TSA procedures recorded during this time frame. Patients with greater than 38% preoperative hematocrit (HCT) were classified as having normal HCT levels. Patients with HCT values between 33% and 38% were classified as having mild anemia. All patients with less than 33% HCT were classified as having moderate/severe anemia. Patient demographic information, preoperative risk factors, and postoperative outcomes were compared among the 3 cohorts. A multivariate logistic regression including demographic factors and comorbidities was performed to determine whether increasing severity of anemia is independently associated with poorer postoperative outcomes.

Results

Of the 15,185 patients included in this study, 11,404 had normal HCT levels, 2962 patients were mildly anemic, and 819 patients had moderate to severe anemia. With increasing severity of anemia, there was an increased average hospital length of stay (1.6 vs. 2.1 vs. 3.0 days, P < .001), rate of readmissions (2.3% vs. 4.8% vs. 7.0%, P < .001), and rate of all reoperations (1.1% vs. 1.8% vs. 3.1%, P < .001). There was a statistically significant increase in both minor (1.9% vs. 2.7% vs. 4.4%, P < .001) and major (1.2% vs. 2.4% vs. 4.3%, P < .001) postoperative complication rates as well. Multivariate analysis identified anemia as an independent predictor of readmissions, reoperations, minor complications, and major complications.

Conclusion

We found increasing severity of anemia to be associated with progressively worse 30-day postoperative outcomes. This is consistent with the outcomes found for increasing severity of anemia in patients receiving other total joint procedures. Using preoperative HCT levels may be a useful tool for predicting the risk of postoperative complications in patients undergoing TSA. This information could be used to further optimize patient selection for primary TSA.

Outcome of a metaphyseal reverse total shoulder replacement in rheumatoid arthritis

AIM

To assess the clinical and radiological results of a metaphyseal reverse total shoulder arthroplasty (rTSA) without diaphyseal stem, in rheumatoid arthritis (RA) patients.

METHODS

Forty-five shoulders in 36 consecutive RA patients (2005-2015) underwent rTSA with a bone impaction technique. Patients were assessed clinically and radiographically preoperatively, at 3 weeks, 3 months, 6 months, 12 months post-operatively, and yearly thereafter, using constant score (CS), pain score, subjective shoulder value (SSV) and patient satisfaction score.

RESULTS

Forty-four shoulders with mean follow-up of 67 months (range 24 m-146 m (12y)) were available for follow-up. Mean age at surgery was 68.7 years (range 39-86). CS improved from 17.5 ± 10.5(SD) (age/sex adjusted 23.9 ± 14.5(SD)) preoperatively to 60.9 ± 17.4 (SD) (age/sex adjusted 86.5 ± 24.5 (SD)) at last follow-up (P < 0.001). Pain score and SSV also significantly improved (p < 0.001). Mean range of movement improved to 140°active forward flexion, 134°active abduction, 47°active external rotation (AER) and 70°active internal rotation (AIR). The results were maintained over time. Combined early and late complication rate was 15.6%, which is lower than described in the literature for RA. No lucencies, loosening, subsidence or stress shielding were evident radiographically.

CONCLUSION

Metaphyseal rTSA without a diaphyseal stem is successful and safe in RA patients. Patients achieve good function and have high satisfaction rates.

LEVEL OF EVIDENCE

Case series: Level IV.

Advanced Templating for Total Shoulder Arthroplasty

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Longitudinal clinical and radiographic success of total shoulder arthroplasty (TSA) is critically dependent on optimal glenoid component position.

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Historically, preoperative templating utilized radiographs with commercially produced overlay implant templates and a basic understanding of glenoid morphology.

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The advent of 3-dimensional imaging and templating has achieved more accurate and precise pathologic glenoid interrogation and glenoid implant positioning than historical 2-dimensional imaging.

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Advanced templating allows for the understanding of unique patient morphology, the recognition and anticipation of potential operative challenges, and the prediction of implant limitations, and it provides a method for preoperatively addressing abnormal glenoid morphology.

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Synergistic software, implants, and instrumentation have emerged with the aim of improving the accuracy of glenoid component implantation. Additional studies are warranted to determine the ultimate efficacy and cost-effectiveness of these technologies, as well as the potential for improvements in TSA outcomes.

Automated muscle elongation measurement during reverse shoulder arthroplasty planning

BACKGROUND

Adequate deltoid and rotator cuff elongation in reverse shoulder arthroplasty is crucial to maximize postoperative functional outcomes and to avoid complications. Measurements of deltoid and rotator cuff elongation during preoperative planning can support surgeons in selecting a suitable implant design and position. Therefore, this study presented and evaluated a fully automated method for measuring deltoid and rotator cuff elongation.

METHODS

Complete scapular and humeral models were extracted from computed tomography scans of 40 subjects. First, a statistical shape model of the complete humerus was created and evaluated to identify the muscle attachment points. Next, a muscle wrapping algorithm was developed to identify the muscle paths and to compute muscle lengths and elongations after reverse shoulder arthroplasty implantation. The accuracy of the muscle attachment points and the muscle elongation measurements was evaluated for the 40 subjects by use of both complete and artificially created partial humeral models. Additionally, the muscle elongation measurements were evaluated for a set of 50 arthritic shoulder joints. Finally, a sensitivity analysis was performed to evaluate the impact of implant positioning on deltoid and rotator cuff elongation.

RESULTS

For the complete humeral models, all muscle attachment points were identified with a median error < 3.5 mm. For the partial humeral models, the errors on the deltoid attachment point largely increased. Furthermore, all muscle elongation measurements showed an error < 1 mm for 75% of the subjects for both the complete and partial humeral models. For the arthritic shoulder joints, the errors on the muscle elongation measurements were <2 mm for 75% of the subjects. Finally, the sensitivity analysis showed that muscle elongations were affected by implant positioning.

DISCUSSION

This study presents an automated method for accurately measuring muscle elongations during preoperative planning of shoulder arthroplasty. The results show that the accuracy in measuring muscle elongations is higher than the accuracy in indicating the muscle attachment points. Hence, muscle elongation measurements are insensitive to the observed errors on the muscle attachment points. Related to this finding, muscle elongations can be accurately measured for both a complete humeral model and a partial humeral model. Because the presented method also showed accurate results for arthritic shoulder joints, it can be used during preoperative shoulder arthroplasty planning, in which typically only the proximal humerus is present in the scan and in which bone arthropathy can be present. As the muscle elongations are sensitive to implant positioning, surgeons can use the muscle elongation measurements to refine their surgical plan.

Is postoperative glucose variability associated with adverse outcomes following shoulder arthroplasty?

BACKGROUND

Postoperative infection after shoulder arthroplasty is a devastating complication. Multiple patient risk factors have been associated with postoperative infection, including increased body mass index and diabetes. Although the association between preoperative glucose control and infection has been established, little is known about the effect of perioperative glycemic control on outcomes following shoulder arthroplasty. The purpose of this study was to investigate the association between postoperative glycemic variability and short-term complications after total shoulder arthroplasty (TSA) and reverse total shoulder arthroplasty (RTSA).

METHODS

A retrospective study was performed at a large, single-specialty center from January 2015 to December 2018. Patients were included if they underwent primary TSA or RTSA with a minimum of 90 days' follow-up and had a minimum of 1 serum glucose value obtained per day of the hospital stay or had ≥3 measurements obtained during the hospital admission period. The primary outcome variable was postoperative infection per accepted definitions of surgical-site infection or periprosthetic joint infection. Secondary outcome variables included stiffness, periprosthetic fracture, periprosthetic dislocation, and reoperation.

RESULTS

In total, 1074 TSAs or RTSAs (in 1032 patients) met the eligibility criteria. The mean patient age was 69.9 ± 8.4 years, and 40.3% of patients had a preoperative diagnosis of diabetes mellitus. Of the patients, 670 (62%) had a calculable coefficient of variation. A younger patient age (median, 65 years [interquartile range (IQR), 13.5 years] vs. 71 years [IQR, 11.0 years]; P = .02) and a preoperative diagnosis of diabetes mellitus (P = .01) showed statistically significant associations with postoperative infection. The first in-hospital glucose measurement beyond the reference tertile of 70-140 mg/dL showed a statistically significant association with postoperative infection, with a median of 128.0 mg/dL (IQR, 43 mg/dL) vs. 167.5 mg/dL (IQR, 37.0 mg/dL; P = .01), whereas the second and third glucose measurements showed no association with postoperative infection. We found no associations between the coefficient of variation and reoperations or complications including surgical-site infection, periprosthetic joint infection, death, postoperative infection, periprosthetic fracture, or stiffness.

CONCLUSION

We found an association between a preoperative diagnosis of diabetes mellitus and postoperative infection following shoulder arthroplasty. We also found that an elevated first glucose measurement is associated with the development of postoperative infection. In-hospital glycemic control, as well as preoperative glycemic control and optimization, may be beneficial for reducing postoperative infections following shoulder arthroplasty.

The Lesser Tuberosity Osteotomy Exposure for Total Shoulder Arthroplasty

Background

The lesser tuberosity osteotomy (LTO) is a commonly employed technique for mobilizing the subscapularis tendon during anatomic total shoulder arthroplasty that is performed through a deltopectoral approach. During this procedure, the lesser tuberosity is osteotomized from the proximal aspect of the humerus while maintaining the strong tendon-to-bone attachment of the subscapularis tendon insertion. After the shoulder arthroplasty is performed, the lesser tuberosity osseous fragment is then resecured to the proximal aspect of the humerus with heavy nonabsorbable suture, which allows for direct bone-to-bone compression and healing of the fragment to the proximal aspect of the humerus. This technique may be utilized for subscapularis tendon mobilization in any primary and some revision anatomic total shoulder arthroplasty procedures.

Description

The procedure is performed as follows. (1) Preoperative planning is performed. (2) The patient is positioned in the semi-upright beach-chair position, and the shoulder girdle and the upper arm are prepared and draped. (3) A standard deltopectoral approach is utilized. (4) A tenotomy of the long head of the biceps tendon is performed, exposing the bicipital groove. (5) An LTO is made from lateral to medial with an oscillating saw and is completed with use of an osteotome. (6) The remaining inferior portion of the subscapularis and capsule are released off of the humerus. (7) The total shoulder arthroplasty is completed up to the point of implantation of the final humeral component. (8) Four drill-holes are made lateral to the bicipital groove and osteotomy site. (9) Heavy nonabsorbable sutures, with or without cerclage wires, are passed from lateral to medial around the humeral stem and passed medial to the osteotomy fragment through the insertion of the subscapularis tendon. (10) The sutures are then tensioned and tied with the arm in 30° of external rotation. (11) The wound is irrigated, dried, and closed in layered fashion.

Alternatives

The most commonly accepted alternative approaches include the subscapularis tenotomy and subscapularis peel techniques.

Rationale

The LTO approach technique was developed to take advantage of bone-to-bone healing and to address concerns regarding poor tendon-to-tendon or tendon-to-bone healing in the subscapularis tenotomy and subscapularis peel exposure techniques, respectively.

Expected Outcomes

Based on numerous published studies, excellent clinical results are achieved with anatomic total shoulder arthroplasty. When comparing surgical techniques involving the subscapularis in Level-I, randomized controlled trials, no significant differences exist among clinical outcomes, range of motion, or strength between the different techniques.

Important Tips

Three-dimensional preoperative templating software allows for the anticipation of potential operative challenges, the prediction of implant limitations, and more accurate assessment of abnormal glenoid morphology and wear patterns.An articulating arm positioner can be helpful in controlling the arm position without the need for an extra surgical assistant.The goal thickness of the LTO is 10 mm. If the osteotomy is made too thin, there is a risk that the repair sutures cut through the lesser tuberosity fragment, leading to subscapularis repair failure.Releasing the capsule from the subscapularis is a critical step to ensure adequate tendon excursion for later repair and restoration of external rotation in arthritic shoulders. However, careful attention must be directed to the position and orientation of the axillary nerve in order to avoid iatrogenic injury during this critical step.Creating the drill-holes lateral to the bicipital groove takes advantage of the very strong and dense bone in that area of the proximal aspect of the humerus, enhancing the integrity of the repair.The tension band suture is critical to aid in further compression of the LTO fragment when the arm is brought into external rotation.Closing the rotator interval substantially increases the strength of the subscapularis repair; however, the closure of the interval must be made with the arm in at least 30° of external rotation in order to avoid iatrogenic motion restriction.Using interrupted nonabsorbable sutures to close the deltopectoral interval at the conclusion of the procedure is helpful in the event that any revision procedure is needed because these sutures will guide the revision surgeon toward making the deltopectoral approach in the correct interval.

Acronyms and Abbreviations

LTO = lesser tuberosity osteotomyROM = range of motionASES = American Shoulder and Elbow SurgeonsWOOS = Western Ontario Osteoarthritis of the Shoulder indexVAS = visual analog scaleSF-36 = 36-Item Short Form Health SurveySST = Simple Shoulder TestDVT = deep-vein thrombosis.

Complications and Readmissions After Reverse and Anatomic Total Shoulder Arthroplasty With Same-day Discharge

BACKGROUND

Recent studies have demonstrated the safety of anatomic total shoulder arthroplasty (TSA) in an outpatient setting. No clinical studies, to date, have specifically analyzed complication and readmission rates after reverse total shoulder arthroplasty (RTSA) with same-day discharge. The purpose of this study was to compare the 90-day complication and readmission rates of patients undergoing TSA and RTSA with same-day discharge.

METHODS

Ninety-eight consecutive patients who underwent 104 shoulder arthroplasties with same-day discharge (52 TSA and 52 RTSA) between 2016 and 2019 were analyzed. Suitability for same-day discharge was determined preoperatively using the standardized criteria. Demographic variables, operative time, 90-day readmission, and complication rates were recorded and compared between groups. Differences between the patients undergoing TSA versus RTSA were evaluated with Student t-test, Mann-Whitney test, or Chi square tests as statistically appropriate and reported as P values.

RESULTS

Average age in the TSA cohort was significantly lower (60.1 ± 7.4 versus 67.5 ± 7.5, respectively; P < 0.001). Total operating room time was significantly shorter in the RTSA cohort (153 ± 30.1 minutes versus 171 ± 20.9). Three minor postoperative complications (5.8%) were observed in the TSA cohort (three seromas) within the 90-day postoperative period. There were four postoperative complications (7.7%) in the RTSA cohort (two postoperative seromas, one periprosthetic fracture, and one dislocation). None of the TSA patients required readmission and 1 RTSA (periprosthetic fracture) patient required readmission within 90 days.

DISCUSSION

RTSA with same-day discharge is a safe option for appropriately selected patients despite significantly increased age. 90-day readmission and complication rates between outpatient TSA and RTSA are similar.

DATA AVAILABILITY

Yes.

TRIAL REGISTRATION NUMBERS

NA.

LEVEL OF EVIDENCE

III (case-control).

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

BACKGROUND

Total shoulder arthroplasty has been demonstrated to be an effective treatment for arthritis of the glenohumeral joint. Prior studies have identified longer operative times as a risk factor for complications after numerous types of procedures. We hypothesized that increased operative time, in 20-min intervals, would be associated with complications following total shoulder arthroplasty.

METHODS

Patients undergoing total shoulder arthroplasty from 2006 to 2015 were identified from the ACS-NSQIP database. Patient demographic information, perioperative parameters, and 30-day outcomes were retrieved. Pearson's Chi-square test and multivariate Poisson regression with robust error variance were used to analyze the relationship of operative time and outcomes.

RESULTS

A total of 10,082 patients were included. Multivariate analysis revealed that for each increase in 20 min of operative time, there were significantly increased rates of any complication (relative risk (RR) 1.24, 95% confidence interval (CI) 1.19-1.26), anemia requiring transfusion (RR 1.33, 95%CI 1.26-1.4), peripheral nerve injury (RR 1.88, 95%CI 1.53-2.31), and urinary tract infection (RR 1.24, 95%CI 1.09-1.41).

DISCUSSION

This study indicates that increasing operative time confers increased risk for postoperative complications following total shoulder arthroplasty. We anticipate the results of this manuscript will be used for provider education, policy decision-making, and potentially to derive algorithms that can improve safety and efficiency in total shoulder arthroplasty.

LEVEL OF EVIDENCE

III.

Results of stemless shoulder arthroplasty: a systematic review and meta-analysis

Stemless shoulder arthroplasty relies solely on cementless metaphyseal fixation and is designed to avoid stem-related problem such as intraoperative fractures, loosening, stress shielding or stress-risers for periprosthetic fractures.

Many designs are currently on the market, although only six anatomic and two reverse arthroplasty designs have results published with a minimum of two-year follow-up.

Compared to stemmed designs, clinical outcome is equally good using stemless designs in the short and medium-term follow-up, which is also the case for overall complication and revision rates.

Intraoperative fracture rate is lower in stemless compared to stemmed designs, most likely due to the absence of intramedullary preparation and of the implantation of a stem.

Radiologic abnormalities around the humeral implant are less frequent compared to stemmed implants, possibly related to the closer resemblance to native anatomy.

Between stemless implants, several significant differences were found in terms of clinical outcome, complication and revision rates, although the level of evidence is low with high study heterogeneity; therefore, firm conclusions could not be drawn.

There is a need for well-designed long-term randomized trials with sufficient power in order to assess the superiority of stemless over conventional arthroplasty, and of one design over another.

Cite this article: EFORT Open Rev 2021;6:35-49. DOI: 10.1302/2058-5241.6.200067

Superior Capsular Reconstruction Provides Sufficient Biomechanical Outcomes for Massive, Irreparable Rotator Cuff Tears: A Systematic Review

PURPOSE

To critically review the literature reporting biomechanical outcomes of superior capsular reconstruction (SCR) for the treatment of massive and/or irreparable rotator cuff tears.

METHODS

A systematic review was performed following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines using the PubMed, MEDLINE, and Cochrane Library databases in August 2020. Cadaveric studies were assessed for glenohumeral translation, subacromial contact pressure, and superior humeral translation comparing SCR with an intact cuff with reference to a torn control state.

RESULTS

A total of 15 studies (142 shoulders) were included in our data analysis. SCR showed improvements in superior humeral translation, subacromial contact force, and glenohumeral contact force when biomechanically compared with the massive and/or irreparably torn rotator cuff. No statistically significant differences were found between SCR and the intact rotator cuff regarding superior humeral translation (standard mean difference [SMD], 2.09 mm vs 2.50 mm; P = .54) or subacromial contact force (SMD, 2.85 mPa vs 2.83 mPa; P = .99). Significant differences were observed between SCR and the intact cuff for glenohumeral contact force only, in favor of the intact cuff (SMD, 1.73 N vs 5.45 N; P = .03).

CONCLUSIONS

SCR may largely restore static restraints to superior humeral translation in irreparable rotator cuff tears, although active glenohumeral compression is diminished relative to the intact rotator cuff.

CLINICAL RELEVANCE

Investigating the biomechanical outcomes of SCR will help surgeons better understand the effectiveness of this treatment option.

Factors Affecting Stability of the Reverse Total Shoulder Arthroplasty: A Cadaveric Biomechanical Study

Background:

The overall objective of this study was to investigate whether a reverse shoulder arthroplasty could provide adequate stability to a shoulder even with extreme soft tissue loss. The specific objectives of this study were: to determine if just the deltoid, conjoined tendon, and triceps are sufficient soft tissues to allow a Reverse Shoulder Arthroplasty (RSA) to provide shoulder stability and to determine the influence of load direction, rotation, shoulder position, and polyethylene thickness on RSA stability in this soft-tissue deficient model.

Methods:

This study utilized six cadaveric shoulders that had all soft tissue removed, with the exception of the deltoid, conjoint tendon, and long head of triceps. A reverse shoulder arthroplasty was then performed (Delta III, DePuy Inc., Warsaw, IN) and an increasing dislocation force was applied perpendicular to the humeral socket centerline until dislocation occurred, or a maximum load of 100 N was reached. This was repeated to measure the effect of four factors: load direction, arm position, polyethylene thickness, and arm rotation on force to dislocation.

Results:

For load direction, there was an increase in force to dislocate an inferior load direction (p=0.01). There was a lower not dislocated percentage and lower survival for a posterior load direction (p=0.02). For arm position, there was a decrease in force for dislocation and lower survival for both abduction and extension arm positions. There was a higher not dislocated percentage for a flexion arm position (p=0.01). For arm rotation, there was a lower not dislocated percentage and lower survival for an external rotation arm position (p=0.03). There was no statistically significant influence of polyethylene thickness (p=0.26).

Conclusion:

The deltoid, conjoined tendon, and triceps are sufficient to stabilize an RSA. Load direction, arm position, and arm rotation were all shown to significantly affect stability. Finally, polyethylene thickness may not affect overall RSA stability in this soft-tissue deficient model.

Level of Evidence:

Basic science study, Biomechanical study.

Outcomes of anatomic shoulder arthroplasty performed on B2 vs. A1 type glenoids

BACKGROUND

Glenoid component malpositioning and glenoid component retroversion have been associated with higher rates of radiolucencies, raising concerns about its implications on glenoid loosening and ultimate failure of anatomic total shoulder arthroplasty (TSA). Although there is literature regarding the relative advantages of techniques to address posterior glenoid bone loss, we are not aware of studies comparing outcomes of TSA on these challenging Walch type B2 glenoids vs. more common A1 glenoids. The purpose of this study is to compare outcomes of TSA performed on A1 glenoids and B2 glenoids treated with asymmetric glenoid reaming.

METHODS

We identified 1045 shoulders that had primary TSAs performed for osteoarthritis in a prospective shoulder arthroplasty registry. Two hundred eighty-nine shoulders met inclusion criteria of a preoperative Walch type A1 (178) or B2 (111) glenoid morphology, treatment with TSA, asymmetric reaming in the B2 group, and a minimum of 2-year clinical and radiographic follow-up. Postoperative radiographs were assessed for lucencies, and patient-reported outcome measures were collected at all follow-up visits.

RESULTS

Follow-up averaged 40 ± 15 months for all patients, and more men presented with a B2 glenoid (80 of 111; 72%) compared with A1 (101 of 178; 57%) (P = .009). Age at surgery (P = .166), dominant-sided surgery (P = .281), body mass index (P = .501), smoking (P = .155), preoperative opioid use (P = .154), and diabetes (P = .331) were not significantly different between groups. Both groups had similar Constant Strength scores preoperatively (A1: 4.7 ± 7.1, and B2: 4.3 ± 7.3) but the B2 group improved significantly more at final follow-up (A1: 10.3 ± 6.2 vs. B2: 12.7 ± 6.7, P = .005). The Total Constant score was also significantly better at follow-up in the B2 glenoid group (P = .039). All other Constant subscales, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), and Single Assessment Numerical Evaluation (SANE) measures showed significant improvement preoperatively to final follow-up (all P <.001) but there were no significant differences between the A1 and B2 glenoid groups (all P > .05). A similar proportion of patients rated their satisfaction as either very satisfied or satisfied between the A1 (160; 90%) and B2 (100; 90%) (P = .613). Lazarus scores were also similar between the A1 and B2 groups (P = .952) as were the rates of humeral radiolucent lines (P = .749) and humeral osteolysis (P = .507).

CONCLUSIONS

Although patients with B2 glenoids may present a more technically challenging anatomic total shoulder arthroplasty, treatment with concurrent asymmetric glenoid reaming produced similar, successful clinical and radiographic early to midterm outcomes for patients undergoing TSA compared with A1 glenoids. Additional follow-up on this cohort will be important to confirm the durability of these early results.

Operative duration-based learning period analysis for reverse and total shoulder arthroplasty: A multicenter study

BACKGROUND

A surgical learning period may be quantified after which operative duration is significantly reduced. We sought to retrospectively quantify and compare surgeon's learning experience for total shoulder arthroplasty and reverse shoulder arthroplasty.

METHODS

We reviewed 2055 shoulder arthroplasty cases from 2011 to 2015 for four early-career and four later-career fellowship-trained shoulder surgeons from four institutions. We plotted consecutive case number versus operative time for each surgeon separately for total shoulder arthroplasty or reverse shoulder arthroplasty. Two-step regression approach was used to determine a plateau point or end of the learning period. Additionally, the mean annual volume of reverse shoulder arthroplasty and total shoulder arthroplasty for each surgeon was plotted against mean surgery duration. Early- and later-career surgeons were compared with regression analysis.

RESULTS

Early-career surgeons demonstrated a significant decrease in operative time with increasing annual case volume for reverse shoulder arthroplasty (p = 0.01; m = -1.1) and total shoulder arthroplasty (p = 0.02; m = -0.8). Three of four early-career surgeons reached a plateau point for either reverse shoulder arthroplasty or total shoulder arthroplasty between 12 and 86 cases.

CONCLUSION

For only early-career surgeons, higher case volume yields decreased operative duration, with improvement more pronounced for reverse shoulder arthroplasty compared to total shoulder arthroplasty. Though the learning period varies, it may be fewer than 90 cases.

The modern use of the extended humeral head (cuff tear arthropathy) hemiarthroplasty

Today, the treatment of osteoarthritis in the rotator cuff–deficient population is largely dominated by reverse shoulder arthroplasty (RSA). Despite the popularity of and increased familiarity with this procedure, the complication rate of RSA remains significant. An extended humeral head hemiarthroplasty may provide a less invasive alternative for select patients with cuff tear arthropathy (CTA) and preserved glenohumeral active elevation. With the indications for reverse arthroplasty expanding to younger patients, there are concerns about the longevity of this implant, as well as the associated revision burden. In the setting of failed RSA, the bone stock available for glenosphere baseplate fixation can be inadequate for reimplantation. The treatment strategies for complex shoulder deformities and failed RSA are limited by patient-specific issues, such as anatomy and risk factors. In this review, we discuss the potential role of extended humeral head hemiarthroplasty (CTA hemiarthroplasty) as a primary surgical option in select patients (1) who have preserved elevation > 90°, (2) who have maintained stability (intact coracoacromial ligament), and (3) who desire to circumvent the complications associated with RSA. Furthermore, CTA hemiarthroplasty may be used for severe glenoid erosion, for a fragmented acromion, and in the revision setting for failed RSA aimed at a reliable salvage procedure.

Short-term safety, function, and quality of life in patients treated with Univers Revers prosthesis: a multicenter 2-year follow-up case series

BACKGROUND

The use of reverse total shoulder arthroplasty (RTSA) has dramatically increased in recent years with the advent of new prosthesis designs regularly entering the market. We define the rate of local complications during the first 2 years after RTSA with the Univers Revers prosthesis and describe the changes in radiologic outcomes, as well as function, pain, satisfaction, and quality of life.

METHODS

This multicenter, prospective case series included rotator cuff tear arthropathy patients who underwent RTSA with the Univers Revers. Incidence percentages of complications and pathologic radiographic changes were documented. Mixed-model linear regression was used to examine changes in range of motion, shoulder function (Constant score, Shoulder Pain and Disability Index, Subjective Shoulder Value), and quality of life (EQ-5D-5L [European Quality of Life 5 Dimensions 5 Level] and EQ-VAS [EuroQol Visual Analog Scale]).

RESULTS

Of 187 patients, 59.4% were women, and the mean age was 75.3 years (range, 56-91 years). Twenty-five percent of patients had a postoperative complication; 5 complications were severe (2.7%, 5 of 187), whereby 2 were implant related (1.1%; 95% confidence interval [CI], 0.1%-3.8%). The incidence of scapular notching was 10.6% (95% CI, 6.5%-16%). After 2 years, abduction, flexion, and abduction strength improved by 54° (95% CI, 50°-58°), 57° (95% CI, 53°-60°), and 5 kg (95% CI, 4-5 kg), respectively (P < .001), whereas external rotation at 0° (1°; 95% CI, -1° to 3°) did not improve (P = .4). The Constant score improved by 39 (95% CI, 38-41); Shoulder Pain and Disability Index, by 50 (95% CI, 47-52); and Subjective Shoulder Value, by 43 (95% CI, 41-45) (P < .001). Furthermore, the EQ-5D-5L index value improved by 0.31 (95% CI, 0.30-0.33), and the EQ-VAS score improved by 16 (95% CI, 14-18) (P < .001).

CONCLUSION

Our case series showed a low complication rate with a consistent clinically relevant and statistically significant improvement across most clinical and patient-reported outcomes for the Univers Revers. Long-term safety requires further investigation.