Neurologic complications of shoulder joint replacement

Increasing Awareness of Complications of Nerve Injury Following Shoulder Surgery: Preventing Delays in Referral and Treatment

BACKGROUND

Nerve injuries remain a challenging complication after shoulder surgery. While most resolve spontaneously, some require surgical intervention. This study describes the characteristics of patients sustaining nerve injuries following shoulder surgery, evaluates referral patterns to nerve surgeons, and characterizes nerve surgeries performed and their outcomes. Increased awareness of these injuries allows patients and providers to be better informed regarding the appropriate management when these complications occur.

METHODS

A retrospective review of referrals with nerve injuries following shoulder surgery between 2007 and 2015 was performed. The final analysis included 65 patients. Data reviewed included demographics, procedure and anesthesia type, and diagnosis of nerve injury. Time to referral to nerve surgeon and proportional changes in the Disabilities of the Arm, Shoulder, and Hand (DASH) scores were determined. Outcomes were categorized as failed, partially successful, and successful based on final follow-up.

RESULTS

Patients were referred following arthroscopic shoulder surgeries (35.4%), shoulder arthroplasties (24.6%), open shoulder procedures (21.5%), and combined open and arthroscopic procedures (18.5%). The mean time to referral was 7.6 months. Nerve injuries involved brachial plexus (33) and individual and multiple peripheral nerve branches (23 and 7, respectively). Twenty-five (38%) nerve injuries demonstrated spontaneous recovery. Thirty-five patients underwent surgical intervention, of which 27 were successful, 3 were partially successful, and 3 failed.

CONCLUSIONS

This is the largest series of patients with iatrogenic nerve injury following shoulder surgeries to date. Our data demonstrate a lack of timely referral to nerve surgeons, especially after arthroscopy. There continues to be a variable injury pattern even among similar surgeries. Despite this, timely surgical intervention, when indicated, can lead to favorable outcomes.

Brachial plexus deficits in patients undergoing shoulder arthroplasty

Background

Nerve deficit following shoulder arthroplasty can cause significant morbidity. We examined the incidence and pattern of nerve injury following shoulder arthroplasty in a University Hospital.

Methods

Retrospective review of all patients undergoing shoulder arthroplasty over a five-year period (September 2014 to August 2019). Patients were identified using clinical codes and relevant data extracted by review of patient records. We excluded patients with preoperative nerve injuries.

Results

220 arthroplasties were performed in 210 patients. The overall nerve deficit rate was 2.3% (5/220). Five nerve deficits occurred following reverse total shoulder arthroplasty (rTSA). In two patients, nerve recovery occurred within 12 months. Two patients had persistent deficits at 12 months. One patient had a deficit at seven months, but incomplete follow up. There was no clear documentation of discussions with clinicians specialising in nerve injury.

Conclusion

Nerve injury rates in our series for rTSA are low and comparable to systematic review data. We purport that for rTSA, adequate soft tissue releases, careful arm positioning and retraction alongside limiting over-lowering the centre of rotation may prevent nerve injuries. A postoperative nerve deficit should warrant an opinion from a specialist in nerve surgery with clear referral pathways to allow efficient access to services.

How common is nerve injury after reverse shoulder arthroplasty? A systematic review

BACKGROUND

Nerve injury following reverse shoulder arthroplasty (RSA) is a known risk factor with wide ranging incidences reported. This systematic review evaluates the overall incidence of nerve injury following primary and revision RSA and summarizes the characteristics of the nerve injuries reported in the current literature.

METHODS

A systematic review was performed using separate database searches (Pubmed, Embase, Web of Science, Cochrane) following the PRISMA guidelines. Search criteria included the title terms "reverse shoulder," "reverse total shoulder," "inverted shoulder," and "inverted total shoulder" with publication dates ranging from 01/01/2010 to 01/01/2022. Studies that reported neurological injuries and complications were included and evaluated for primary RSA, revision RSA, number of nerve injuries, and which nerves were affected.

RESULTS

After exclusion, our systematic review consisted of 188 articles. A total of 40,146 patients were included, with 65% female. The weighted mean age was 70.3 years. The weighted mean follow-up was 35.4 months. The rate of nerve injury after RSA was 1.3% (510 of 40,146 RSAs). The rate of injury was greater in revision RSA compared to primary RSA (2.4% vs. 1.3%). Nerve injury was most common in RSAs done for a primary diagnosis of acute proximal humerus fracture (4.0%), followed by cuff tear arthropathy (3.0%), DJD (2.6%), and inflammatory arthritis (1.7%). Massive rotator cuff tears and post-traumatic arthritis cases had the lowest nerve injury rates (1.0% and 1.4%, respectively). The axillary nerve was the most commonly reported nerve that was injured in both primary and revision RSA (0.6%), followed by the ulnar nerve (0.26%) and median nerve (0.23%). Brachial plexus injury was reported in 0.19% of overall RSA cases.

CONCLUSION

Based on current English literature, nerve injuries occur at a rate of 1.3% after primary RSA compared with 2.4% after revision RSA. The most common nerve injury was to the axillary nerve (0.64%), with the most common operative diagnosis associated with nerve injury after RSA being acute proximal humerus fracture (4.0%). Surgeons should carefully counsel patients prior to surgery regarding the risk of nerve injury.

Intraoperative and early postoperative complications of reverse shoulder arthroplasty: A current concepts review

Background

Reverse shoulder arthroplasty is a common procedure performed for a variety of shoulder pathologies.

Aims and objectives

This current concept review evaluates the intraoperative and early postoperative complications, with a specific focus given to neurological and vascular injury, fracture, dislocation and venous thromboembolism.

Conclusion

A detailed knowledge of potential complications will allow surgeons to mitigate risk and maximise outcomes.

Prevalence, management, and outcomes of nerve injury after shoulder arthroplasty: a case-control study and review of the literature

Background

Neurologic injury is a rare and potentially devastating complication of shoulder arthroplasty. Patients typically present with a mixed plexopathy or mononeuropathy, most commonly affecting the axillary and radial nerves. Given the paucity of studies available on the topic, our goal was to elucidate the prevalence of nerve injury after shoulder arthroplasty and to describe the treatment course and outcomes of neurologic injuries.

Methods

This is a retrospective case-control study performed at a single, urban, academic institution. Consecutive patients who underwent anatomic total shoulder arthroplasty (TSA) or reverse shoulder arthroplasty (RSA) by a single surgeon from 2014 to 2020 were reviewed, and patients with a documented nerve injury were identified. A control group of patients without nerve injury were selected in a 2:1 ratio controlling for age and procedure type (TSA vs. RSA; primary vs. revision). Data collected included demographics, comorbidities as per the Charlson Comorbidity Index, radiographic evaluations, surgical and implant details, patient-reported outcome measures, and perioperative complications.

Results

Of 923 patients, 33 (3.6%) sustained an iatrogenic nerve injury: 10 (2.1%) after TSA, 23 (5.0%) after RSA, and 3 (7.8%) after revision arthroplasty. Axillary mononeuropathy was most common (42%), followed by brachial plexopathies (18%). There was no significant difference in age, sex, race, body mass index, and preoperative diagnoses between groups. Patients with nerve injury had fewer comorbidities (Charlson Comorbidity Index <3, 33 vs. 65%, P<.001). Patients with nerve injury had higher rates of cervical spine pathology (15 vs. 6%; P = .15) and increased postoperative lateralization (8.9 mm [7.2] vs. 5.5 mm [7.3]; P<.06). The majority (91%) were managed with observation alone. Three (9%) underwent an additional procedure: carpal tunnel release (1, 3%), ulnar nerve decompression (1, 3%), and ulnar nerve transposition (1, 3%) for peripheral compressive neuropathies. At the final follow-up, 19 (57%) nerves fully recovered, and 14 (43%) showed mild residual sensorimotor dysfunction. The mean time to first sign of recovery and ultimate recovery were 11 (7.2) and 36 (23.5) weeks, respectively. At the final follow-up, patients with nerve injury performed worse on patient-reported outcomes, including visual analog score pain (2.2 vs. 1.0, P<.001), American Shoulder and Elbow Surgeons score (67.8 vs. 84.8, P<.001), and Single Assessment Numeric Evaluation scores (62 vs. 77, P = .009).

Discussion

Nerve injury after shoulder arthroplasty is rare, occurring in 3.6% of our patient population. Axillary mononeuropathy and brachial plexopathies are the most common. Most patients can be managed expectantly with observation and will recover at least partial nerve function, although clinical outcomes remain inferior to those without nerve complication.

Persistent and profound peripheral nerve injuries following reverse total shoulder arthroplasty

BACKGROUND

Peripheral nerve injuries associated with reverse total shoulder arthroplasty (rTSA) are rarely reported and are often dismissed as neuropraxias, particularly in the setting of perioperative nerve blocks. The purpose of this study was to evaluate nerve injuries following rTSA to determine if there is a pattern of injury and to evaluate outcomes of patients who sustain an intraoperative nerve injury.

METHODS

A retrospective review was performed identifying patients who underwent rTSA and had a concomitant major nerve injury who were referred to a multidisciplinary peripheral nerve injury clinic. Demographic data, preoperative nerve block use, physical examination, electrodiagnostic studies, injury pattern, and time from injury to referral was collected. Radiographs, Quick Disabilities of the Arm, Shoulder and Hand questionnaire (QuickDASH) score, and outcomes surveys were obtained at final follow-up.

RESULTS

Twenty-two patients were identified with postoperative nerve injuries. Average time from injury to referral was 9.0 months, with 18.8 months' follow-up. Eight patients had undergone prior shoulder surgery, and 11 patients had prior shoulder trauma. Injury patterns were variable and involved diffuse pan-plexopathies with severity localized to the posterior and medial cords (11), the upper trunk (5), lateral cord (2), and axillary nerve (4). The average postoperative acromiohumeral distance (AHD) was 3.7 cm, with an average change of 2.9 cm. The average postoperative lateral humeral offset (LHO) was 1.1 cm, with an average change of 0.2 cm. Seventeen patients were confirmed to have undergone preoperative nerve blocks, which were initially attributed as the etiology of nerve injury. Eighteen patients were initially treated with observation: 11 experienced residual debilitating neuropathic pain and/or disability, and 7 had substantial improvement. One patient underwent nerve transfers, whereas the others underwent procedures for hand dysfunction improvement. The average QuickDASH score was 53.5 at average of 4 years post rTSA.

CONCLUSIONS

Although uncommon, permanent peripheral nerve injuries following rTSA do occur with debilitating effects. Preoperative regional blocks were used in most cases, but none of the blocks could be directly attributed to the nerve injuries. Nerve injuries were likely secondary to traction at the time of arthroplasty and/or substantial distalization and lateralization of the implants. Patients with medial cord injuries had the most debilitating loss of hand function. Surgeons should be cognizant of these injuries and make a timely referral to a peripheral nerve specialist.

Peripheral nerve stimulation through a 'dry' peripheral nerve catheter for shoulder analgesia: a case report

Revision shoulder surgery can pose significant analgesic challenges as locoregional blocks are often avoided to enable early recognition of iatrogenic nerve injuries. Our case describes the utilisation of pre-operative and intra-operative low-frequency percutaneous peripheral nerve stimulation via a 'dry' interscalene catheter, inserted pre-operatively for a patient presenting for revision total shoulder arthroplasty who was experiencing significant shoulder joint pain despite a prior total shoulder arthroplasty. The clinical considerations and safety aspects are discussed further.

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.

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.

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

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

Risk Factors, Management, and Prognosis of Brachial Plexopathy Following Reverse Total Shoulder Arthroplasty

Brachial plexus injuries can have a significant impact on patient outcomes following RTSA by slowing the overall recovery and return of function. Risk factors for brachial plexopathy include traction injury related to arm positioning and exposure during the procedure, direct nerve injury from surgical dissection, and compression injury from retractor placement. Risk of nerve injury can be minimized by limiting the time spent with the arm extended and externally rotated and avoiding excessive traction on the arm during humeral preparation and implant insertion. Prompt identification of postoperative brachial plexopathy is important to optimize the recovery of function.

Concomitant Total Shoulder Arthroplasty and Ipsilateral Carpal Tunnel Release: Is it Safe?

PURPOSE

Symptomatic carpal tunnel syndrome in patients with advanced ipsilateral glenohumeral arthritis requiring total shoulder arthroplasty (TSA) may be easily overlooked. Even when diagnosed beforehand, most upper extremity surgeons have historically chosen to perform TSA and carpal tunnel release (CTR) separately. We hypothesized that combined single-stage TSA and CTR is feasible and yields results comparable with those when the 2 procedures are performed separately, while avoiding 2 surgeries.

METHODS

This was a retrospective review of patients who underwent single-stage primary TSA and ipsilateral CTR between 2015 and 2019. The shoulder outcomes included pain, range of motion, and validated quality of life (QoL) questionnaires: Veterans RAND 12-Item Health Survey (VR-12) and Penn Shoulder Score. The CTR outcomes included pain, grip, pinch, VR-12, shortened Disabilities of the Arm, Shoulder, and Hand Questionnaire (QuickDASH), and Boston Carpal Tunnel Questionnaire. The time to the initiation of rehabilitation and complications were also analyzed. The comparison group consisted of patients who underwent independent TSA or CTR during the same period.

RESULTS

Forty-one patients underwent concomitant TSA and CTR, 248 underwent isolated TSA, and 154 underwent isolated CTR. The shoulder outcomes of patients who underwent the combined procedure were similar to those of patients who underwent isolated TSA in terms of pain, range of motion, general QoL (VR-12), and shoulder-specific QoL (Penn Shoulder Score). The outcomes of patients who underwent the combined procedure were similar to those of patients who underwent isolated CTR in terms of pain, grip and pinch, general QoL (VR-12), QuickDASH, and Boston Carpal Tunnel Questionnaire. The time to the initiation of rehabilitation was also comparable.

CONCLUSIONS

Concomitant CTR and TSA are feasible. The functional outcomes and QoL of patients who underwent the concomitant treatment were comparable with those of patients who underwent the 2 procedures separately.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Common Focal Neuropathies in the Hospitalized Patient

Neuropathies are a common problem encountered by neurologist in the hospitalized setting. Nerve injury may occur secondary to compression, stretch, and direct trauma, among other causes. Common focal neuropathies include the ulnar, median, and radial nerve in the upper extremities and sciatic, peroneal, and femoral nerve in the lower extremities. Surgical and obstetric risk factors are especially important considerations in evaluation of patients with focal neuropathies. Treatment is either conservative therapy or surgery depending on the mechanism of injury and extent of recovery.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

Prevention and Treatment of Nerve Injuries in Shoulder Arthroplasty

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

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

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

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

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

Complications of reverse shoulder arthroplasty: a concise review

Reverse shoulder arthroplasty is an ideal treatment for glenohumeral dysfunction due to cuff tear arthropathy. As the number of patients treated with reverse shoulder arthroplasty is increasing, the incidence of complications after this procedure also is increasing. The rate of complications in reverse shoulder arthroplasty was reported to be 15%-24%. Recently, the following complications have been reported in order of frequency: periprosthetic infection, dislocation, periprosthetic fracture, neurologic injury, scapular notching, acromion or scapular spine fracture, and aseptic loosening of prosthesis. However, the overall complication rate has varied across studies because of different prosthesis used, improvement of implant and surgical skills, and different definitions of complications. Some authors included complications that affect the clinical outcomes of the surgery, while others reported minor complications that do not affect the clinical outcomes such as minor reversible neurologic deficit or minimal scapular notching. This review article summarizes the processes related to diagnosis and treatment of complications after reverse shoulder arthroplasty with the aim of helping clinicians reduce complications and perform appropriate procedures if/when complications occur.

Conjoint tendon release for persistent anterior shoulder pain following reverse total shoulder arthroplasty

Background

Persistent anterior shoulder pain is an under-reported complication after reverse total shoulder arthroplasty (RTSA). The purpose of this study was to determine the effectiveness of open conjoint tendon release in patients with anterior shoulder pain due to conjoint tendinitis after RTSA.

Methods

Open conjoint tendon release was performed by the senior author from June 2014 to November 2018 in patients with persistent anterior shoulder pain after RTSA. Patients were evaluated preoperatively and at a minimum of 1 year postoperatively by phone interview with patient-reported outcome scores including a visual analog scale score for pain and the American Shoulder and Elbow Surgeons score.

Results

We evaluated 11 of 12 patients (92% follow-up) at a minimum of 1 year (average, 27 ± 11 months) after conjoint tendon release. American Shoulder and Elbow Surgeons and visual analog scale pain scores improved from 29.0 ± 22.1 and 7.3 ± 2.0, respectively, preoperatively to 58.2 ± 30.6 and 3.1 ± 3.5, respectively, postoperatively, after open conjoint tendon release (P = .02 and P = .003, respectively). Of the patients, 45% (5 of 11) reported improvement but with some coracoid pain after the release whereas 55% (6 of 11) reported no coracoid pain after the release. No complications occurred as a result of the release, and no patients required reoperation.

Conclusion

Our results suggest that conjoint tendinitis may be a cause of persistent postoperative anterior shoulder pain after RTSA and open conjoint tendon release is a successful treatment.

Neurologic deficit after reverse total shoulder arthroplasty: correlation with distalization

BACKGROUND

Neurologic problems after reverse total shoulder arthroplasty (RTSA) have been reported, but there are a lack of studies regarding which nerve(s) are damaged and the outcomes for the patients who had neurologic complications after RTSA. The purpose of this study was to assess the prevalence and outcomes of neurologic deficit after RTSA and to evaluate the correlation between nonanatomic rearrangement of the shoulder joint and neurologic complications after RTSA. We hypothesized that the neurologic deficit was associated with excessive distalization or lateralization of the humerus after RTSA.

METHODS

RTSA was performed on 182 consecutive shoulders with cuff tear arthropathy. Comparative analysis was performed on 34 shoulders with (group 1) and 148 shoulders without (group 2) neurologic deficit.

RESULTS

The mean follow-up period in the study was 58.5 months (range: 24-124). The mean age was 71.5 ± 7.7 years in group 1 and 73.1 ± 7.2 years in group 2. Neurologic deficit after RTSA was found in 34 shoulders (19%). The mean postoperative acromiohumeral distance was 34.1 ± 11.0 mm in group 1 and 29.4 ± 7.6 mm in group 2 (P = .015). Significant differences in terms of postoperative distalization of the humerus were seen between group 1 (24.5 ± 9.4 mm) and group 2 (20.5 ± 8.3 mm) (P = .009). The most common forms of neurologic deficit after RTSA were axillary nerve (41.2%) and radial nerve (15%) injuries. Thirty shoulders (88%) had neuropraxia, and 4 shoulders (12%) had axonotmesis. By conservative treatment, all patients with neurologic complications achieved complete recovery without any additional surgery; the mean recovery period was 7.4 months (range: 2-38 months).

CONCLUSION

Neurologic deficit occurred in 19% of patients who underwent RTSA, and it was significantly correlated with humeral distalization after surgery. Axillary nerve was mostly involved, and all patients with neurologic deficit achieved complete recovery without any additional surgery.

Delta Xtend reverse shoulder arthroplasty - Results at a minimum of five years

BACKGROUND

Reverse shoulder arthroplasty provides predictable pain relief and improvements in function, but concerns remain regarding complication rates and there is little long-term outcome data. The aim of this study was to review the clinical and radiographic outcomes of the Delta Xtend reverse shoulder arthroplasty at a minimum of five years.

METHODS

Ninety-six Delta Xtend reverse shoulder arthroplasty procedures were performed in 93 patients. There were 41 males and 52 females with an average age of 74.9 years. All available patients returned for clinical and radiographic analysis, including completion of patient reported outcome measures.

RESULTS

The complication rate was 9.4%. There were three revisions (3.1%) and two other reoperations (2.1%). Fifty-nine shoulders were available for review at an average of 81 months. Average forward flexion was 142°. Average American Shoulder and Elbow Assessment Score improved from 27.6 to 78.5 (p<0.001). Radiolucent lines and/or proximal bone resorption was seen in 35.4%. Scapula notching was observed in 69.1%, with Grade III or IV notching in 20%. These findings had no effect on patient reported outcome measures.

DISCUSSION

This study confirms the clinical benefits of reverse shoulder arthroplasty, with improvements maintained out to 10 years. The high rate of scapula notching remains a concern. Further study is needed to fully understand the clinical significance of notching, as well as the potential benefits of newer implant designs.

A 3-arm randomized clinical trial comparing interscalene blockade techniques with local infiltration analgesia for total shoulder arthroplasty

BACKGROUND

The ideal analgesic modality for total shoulder arthroplasty (TSA) remains controversial. We hypothesized that a multimodal analgesic pathway incorporating continuous interscalene blockade (ISB) provides better analgesic efficacy than both single-injection ISB and local infiltration analgesia.

METHODS

This single-center, parallel, unblinded, randomized clinical trial evaluated 129 adults undergoing primary TSA. Patients were allocated to single-injection ISB, continuous ISB, or local infiltration analgesia. The primary outcome was the Overall Benefit of Analgesia Score (range, 0 [best] to 28 [worst]) on postoperative day 1. Additional outcomes included pain scores, opioid consumption, quality of life, and postoperative complications in the first 24 hours, at 3 months, and at 1 year.

RESULTS

We analyzed 125 patients (42 with single-injection ISB, 41 with continuous ISB, and 42 with local infiltration analgesia). The Overall Benefit of Analgesia Score was significantly improved in the continuous group (median [25th percentile, 75th percentile], 0 [0, 2]) compared with the single-injection group (2 [1, 4]; P = .002) and local infiltration analgesia group (3 [2, 4]; P < .001). Pain scores were significantly lower in the continuous group compared with the local infiltration analgesia group (P < .001 for all time points) and after 12 hours from ward arrival compared with the single-injection group (median [25th percentile, 75th percentile], 1.0 [0.0, 2.8] vs. 2.5 [0.0, 4.0]; P = .016). After postanesthesia recovery discharge, opioid consumption (oral morphine equivalents) was significantly lower in the continuous group (median [25th percentile, 75th percentile], 7.5 mg [0.0, 25.0 mg]) than in the local infiltration analgesia group (30 mg [15.0, 52.5 mg]; P < .001) and single-injection group (17.6 mg [7.5, 45.5 mg]; P = .010). No differences were found across groups for complications, 3-month outcomes, and 1-year outcomes.

CONCLUSION

Continuous ISB provides superior analgesia compared with single-injection ISB and local infiltration analgesia in the first 24 hours after TSA.

Incidence of clinically evident isolated axillary nerve injury in 869 primary anatomic and reverse total shoulder arthroplasties without routine identification of the axillary nerve

Background

It has been suggested that, during primary shoulder arthroplasty, surgeons should identify the axillary nerve through direct visualization, palpation, or the “tug test” to prevent iatrogenic nerve injury. Our goal was to document the rate of isolated axillary nerve injury (IANI) in patients who had undergone primary anatomic total shoulder arthroplasty (TSA) or reverse total shoulder arthroplasty (RTSA) without routine identification of the axillary nerve.

Methods

Data on 869 cases of primary shoulder arthroplasty (338 TSAs and 531 RTSAs) performed by 1 surgeon between 2003 and 2017 were reviewed. Neither the tug test nor identification of the axillary nerve through palpation or visualization was used in any case. The primary outcome was new IANI documented within 3 months after arthroplasty. The frequency of IANI was summarized using point estimates and 95% confidence intervals (CIs).

Results

Six cases met the criteria for IANI. The overall incidence of IANI was 0.7% (95% CI, 0.3%-1.4%). The incidence of IANI was 0.3% (95% CI, 0%-1.6%) after TSA and 0.9% (95% CI, 0.3%-2.1%) after RTSA. All IANIs were cases of neurapraxia, and all patients had experienced complete neurologic recovery at last follow-up.

Conclusion

Complete, permanent IANI resulting from direct surgical trauma during primary shoulder arthroplasty can be avoided without using the tug test or routine identification of the nerve. A low incidence of partial temporary IANI can be expected, which may be related to indirect traction injuries.

Lateralization of the glenosphere in reverse shoulder arthroplasty decreases arm lengthening and demonstrates comparable risk of nerve injury compared with anatomic arthroplasty: a prospective cohort study

HYPOTHESIS

Grammont-style reverse shoulder arthroplasty (RSA) has an increased risk of nerve injury compared with anatomic total shoulder arthroplasty (TSA) due to arm lengthening. We hypothesized that an RSA with a lateralized glenosphere and 135° neck-shaft angle would reduce humeral lengthening and decrease the risk of nerve injury to the level of a TSA.

METHODS

The study prospectively enrolled 50 consecutive patients undergoing RSA (n = 30) or TSA (n = 20) as determined by a power analysis based on previous research for our institution. Intraoperative neuromonitoring was used to detect nerve alerts during 4 distinct stages of the procedure. Preoperative and postoperative arm lengths were measured on scaled radiographs. Patients were examined immediately postoperatively and at follow-up visits for neurologic complications.

RESULTS

Mean motor and sensory nerve alerts per case were similar for TSA and RSA (motor: TSA, 1.5 ± 2; RSA, 1.5 ± 2; P = .96; sensory: TSA, 0.6 ± 0.9; RSA, 0.2 ± 0.6; P = .06). The mean change in arm length was 3 ± 7 mm in the TSA cohort vs. 14 ± 7 mm in the RSA cohort (P = .0001). Temporary neurologic changes postoperatively were noted in 1 TSA and 1 RSA patient, amounting to a 4% incidence of nerve injury.

CONCLUSIONS

An RSA design with a lateralized glenosphere and a lower neck-shaft angle decreases arm lengthening compared with the Grammont design. The reduction in lengthening appears to eliminate the historically increased risk of neurologic injury associated with RSA relative to TSA.