Incidence and risk factors for neurological injury after interscalene peripheral nerve block at an academic institution

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.

Emergency Department Utilization After Administration of Peripheral Nerve Blocks for Upper Extremity Surgery

BACKGROUND

The purpose of this study was to determine the impact of upper extremity peripheral nerve blocks on emergency department (ED) utilization after hand and upper extremity surgery.

METHODS

We reviewed all outpatient upper extremity surgeries performed in a single Midwestern state between January 2009 and June 2019 using the Indiana Network for Patient Care. These encounters were used to develop a database of patient demographics, comorbidities, concurrent procedures, and postoperative ED visit utilization data. We performed univariate, bivariate, and multivariate logistic regression analyses.

RESULTS

Among 108 451 outpatient surgical patients, 9079 (8.4%) received blocks. Within 1 week of surgery, a greater proportion of patients who received peripheral nerve blocks (1.4%) presented to the ED than patients who did not (0.9%) (P < .001). The greatest risk was in the first 2 postoperative days (relative risk, 1.78; P < .001). Pain was the principal reason for ED utilization in the block cohort (53.6%) compared with those who did not undergo a block (35.1%) (P < .001). When controlling for comorbidities and demographics, only peripheral nerve blocks (adjusted odds ratio [OR], 1.71; P = 0.007) and preprocedural opioid use (adjusted OR, 1.43; P = .020) conferred an independently increased risk of ED utilization within the first 2 postoperative days.

CONCLUSIONS

Peripheral nerve blocks used for upper extremity surgery are associated with a higher risk of unplanned ED utilization, most likely related to rebound pain. Through proper patient education and pain management, we can minimize this unnecessary resource utilization.

Patient Complications after Interscalene Block: A Retrospective Comparison of Liposomal Bupivacaine to Nonliposomal Bupivacaine

Background

The purpose of this study was to investigate if the addition of liposome bupivacaine (LB) to an interscalene block (ISB) had an effect on the number of patients with surgical- or block-related complications.

Methods

This was a single-center retrospective chart view performed by identifying patients who received an ISB from January 1, 2014, through April 26, 2018, at the University of Minnesota. 1,518 patients were identified who received an ISB (LB = 784, nonliposomal bupivacaine = 734). Patients were divided into two groups those who did receive liposome bupivacaine in their ISB and those who did not receive liposome bupivacaine in their ISB. Medical records were individually reviewed for surgical procedure, block medications, complications related to the block or surgical procedure, phone calls to the healthcare system for issues related to opioids or pain within 3 and within 30 days, readmissions within 30 days, and emergency room visits for complications within 3 and 30 days.

Results

There was no significant difference in the number of patients with surgical or anesthetic complications. Only phone calls for pain within 3 days were significantly different. The LB group had 3.2% of patients call compared to 5.6% in the nonliposomal bupivacaine group (aOR = 1.71 (95% CI: 1.04–2.87), p=0.036). We found no significant difference in any of the other secondary outcomes.

Conclusions

The use of LB in an ISB demonstrated no significant difference compared to nonliposomal bupivacaine in numbers of complications, emergency room visits, and readmissions.