Risk Factors for a False-Negative Examination in Complete Upper Extremity Nerve Lacerations.

Background: Many patients with complete nerve lacerations after upper extremity trauma have a documented normal peripheral nerve examination at the time of initial evaluation. The purpose of this study was to determine whether physician-, patient-, and injury-related factors increase the risk of false-negative nerve examinations. Methods: A statewide health information exchange was used to identify complete upper extremity nerve lacerations subsequently confirmed by surgical exploration at 1 pediatric and 2 adult level I trauma centers in a single city from January 2013 to January 2017. Charts were manually reviewed to build a database that included Glasgow Coma Scale score, urine drug screen results, blood alcohol level, presence of concomitant trauma, type of injury, level of injury, laterality, initial provider examination, and initial specialist examination. Bivariate and multivariable analyses were performed to evaluate risk factors for a false-negative examination. Results: Two hundred eighty-eight patients met inclusion criteria. The overall false-negative examination rate was 32.5% at initial encounter, which was higher among emergency medicine physicians compared with extremity subspecialists (P < .001) and among trauma surgeons compared with surgical subspecialists (P = .002). The false-negative rate decreased to 8% at subsequent encounter (P < .001). Risk factors for a false-negative nerve examination included physician specialty, a gunshot wound mechanism of injury, injury at the elbow, and age greater than 71 years. Conclusion: There is a high false-negative rate among upper extremity neurotmesis injuries. Patients with an injury pattern that may lead to nerve injury warrant prompt referral to an upper extremity specialist in an effort to optimize outcomes.

Reconstruction of Upper Third Ear Defects: Utility of a Limited Tanzer Reduction.

BACKGROUND: Large ear defects (>3 cm) present a significant reconstructive challenge and often require extensive operations, which can lead to donor-site morbidity and contour abnormalities. Through our case series, we propose a limited Tanzer reduction, a novel modification of the well-recognized Tanzer technique, as a potential reconstructive option for traumatic and oncologic upper third ear defects. METHODS: We retrospectively reviewed patients who underwent planned ear reconstruction for large ear defects (>3 cm) at a university center by a single surgeon (WPT) over a five-year period. Demographics, complications, and need for revision surgery were recorded. A satisfaction survey was also completed. RESULTS: Five patients met our inclusion criteria as they underwent ear reconstruction with the limited Tanzer reduction. All reconstructions followed oncologic resection for cutaneous malignancy. The mean follow-up was 760.2 days. No complications were encountered, and no revisions were required. All cases had good aesthetic outcomes. The satisfaction survey revealed no self-image distortion or social obstacles following the reconstruction. CONCLUSION: The proposed limited Tanzer reduction technique was shown to be a safe, viable, functionally and aesthetically pleasing option for the reconstruction of large defects of the ear and thus should be part of the armamentarium of the reconstructive surgeon.

Ultrasonographic Diagnosis of Thoracic Outlet Syndrome Secondary to Brachial Plexus Piercing Variation.

Structural variations of the thoracic outlet create a unique risk for neurogenic thoracic outlet syndrome (nTOS) that is difficult to diagnose clinically. Common anatomical variations in brachial plexus (BP) branching were recently discovered in which portions of the proximal plexus pierce the anterior scalene. This results in possible impingement of BP nerves within the muscle belly and, therefore, predisposition for nTOS. We hypothesized that some cases of disputed nTOS result from these BP branching variants. We tested the association between BP piercing and nTOS symptoms, and evaluated the capability of ultrasonographic identification of patients with clinically relevant variations. Eighty-two cadaveric necks were first dissected to assess BP variation frequency. In 62.1%, C5, superior trunk, or superior + middle trunks pierced the anterior scalene. Subsequently, 22 student subjects underwent screening with detailed questionnaires, provocative tests, and BP ultrasonography. Twenty-one percent demonstrated atypical BP branching anatomy on ultrasound; of these, 50% reported symptoms consistent with nTOS, significantly higher than subjects with classic BP anatomy (14%). This group, categorized as a typical TOS, would be missed by provocative testing alone. The addition of ultrasonography to nTOS diagnosis, especially for patients with BP branching variation, would allow clinicians to visualize and identify atypical patient anatomy.

Anatomical variations in the brachial plexus roots: implications for diagnosis of neurogenic thoracic outlet syndrome.

Neurogenic thoracic outlet syndrome (NTOS) is the most common type of TOS. Typically it results from impingement of the neurovasculature as it passes between the anterior and middle scalene muscles; this classic anatomical relationship being the foundation of clinical diagnosis. Positional testing relies on vascular compromise occurring when the subclavian artery is compressed in this space. This study describes several anatomical variations observed in this relationship. Sixty-five cadavers (35m/30f) were assessed to determine the frequency and extent of brachial plexus branching variants. A total of thirty-one variations from "classic" anatomy were observed (47.7%). In two specimens (3.1%), the entire superior trunk coursed completely anterior to the anterior scalene in a position of relative vulnerability. In 27 instances, a portion of or the entire superior trunk pierced the anterior scalene muscle, and in two, the middle trunk also pierced the muscle belly. Interestingly, while two bilateral branching variations were observed, the majority occurred unilaterally, and almost exclusively on the left side. There were no sex differences in frequency. The high frequency of these variations and their potential to predispose patients to neurogenic TOS suggest that current diagnostic methods may be insufficient in clinical diagnosis. Due to lack of vascular compromise, patients with the piercing variant would not display positive signs on the traditional positional tests. The use of ultrasound to determine the route of the brachial plexus could determine whether this variation is present in patients who suffer from TOS symptoms but lack a diagnosis based on traditional positional testing.