John W. Norbury

Tarsal Tunnel Syndrome Secondary to Suture Material Within the Tibial Artery: A Sonographic Diagnosis

A 58-year-old man presented to a sports medicine clinic with loss of sensation in the heel of his right foot after a repair of an Achilles tendon rupture 6 mos earlier. The tendon fibers were sutured together with number 5 Fiberwire augmented with Vicryl sutures. Postoperative course included standard physical therapy and CAM boot protection of the healing tendon. He denied pain, weakness, or other symptoms. Neurologic examination revealed decreased sensation to light touch and pin prick in a well circumscribed region on the heel of his foot, with normal findings in motor and reflex examination. An ultrasound of the tibial nerve medial to the Achilles tendon and 3 cm posterior to the medial mallelous revealed a suture impinging on the anterior superior aspect of the nerve in short and long axis (Fig. 1). The suture material was within the tibial artery and impinging on the nerve. The tendon was otherwise well healed and intact. Isolated tibial mononeuropathies at the ankle are uncommon entities, with an incidence of tarsal tunnel syndrome varying between 0.58% (Steinitz et al.) and 0.5% (Oh et al.) of patients who present for electrodiagnostic evaluations. Recently, sonography has been advocated to assist in the diagnosis of tarsal tunnel syndrome. Part of the controversy regarding the incidence of these lesions relates to the very complicated anatomy. In this vignette, the authors report an isolated involvement of the calcaneal branch of the tibial nerve. The sonogram reveals a relatively posterior position of the suture material that corresponds to the anatomy of the nerve. This vignette also illustrates howneuromusculoskeletal ultrasound can be useful to quickly, painlessly, and economically diagnose nerve lesions. REFERENCES 1. Steinitz ES, Singh S, Saeed MA: Diagnostic tests help clarify tarsal tunnel mystery. BioMechanics 1999;6:43Y51

Sonographic Measurements of the Ulnar Nerve at the Elbow With Different Degrees of Elbow Flexion

To determine whether there were differences in the cross‐sectional area (CSA) and the flattening ratio of the normative ulnar nerve as it passes between the medial epicondyle and the olecranon at 30° of elbow flexion versus 90° of elbow flexion.

Improving the Performance Time and Accuracy of Ultrasound-Guided Interventions: A Randomized Controlled Double-Blind Trial of the Line-of-Sight Approach and the “APPLES” Mnemonic: Line-of-Sight Approach for Ultrasound-Guided Interventions

To determine whether the line‐of‐sight approach improved the performance time and accuracy of ultrasound (US)‐guided needle placement targeting the subdeltoid bursa in a cadaver among novice operators compared to the side approach. A secondary objective was to determine whether participants thought the APPLES (angle, position, perpendicular, line up, entry, sweep) mnemonic was a helpful guide for performing the procedure.

Predicting the risk of acute care readmissions among rehabilitation inpatients: A machine learning approach

INTRODUCTION Readmission from inpatient rehabilitation facilities to acute care hospitals is a serious problem. This study aims to develop a predictive model based on machine learning algorithms to identify patients at high risk of readmission. METHODS A retrospective dataset (2001-2017) including 16,902 patients admitted into a large inpatient rehabilitation facility in North Carolina was collected in 2017. Three types of machine learning models with different predictors were compared in 2018. The model with the highest c-statistic was selected as the best model and further tested by using five sets of training and validation data with different split time. The optimum threshold for classification was identified. RESULTS The logistic regression model with only functional independence measures has the highest validation c-statistic at 0.852. Using this model to predict the recent 5 years acute care readmissions yielded high discriminative ability (c-statistics: 0.841-0.869). Larger training data yielded better performance on the test data. The default cutoff (0.5) resulted in high specificity (>0.997) but low sensitivity (<0.07). The optimum threshold helped to achieve a balance between sensitivity (0.754-0.867) and specificity (0.747-0.780). CONCLUSIONS This study demonstrates that functional independence measures can be analyzed by using machine learning algorithms to predict acute care readmissions, thus improving the effectiveness of preventive medicine.

Poster 306: Beyond Saturday Night: A Case Series of Radial Neuropathy in the Arm Diagnosed by Ultrasound in Conjunction with Electrodiagnosis

Disclosures: Austin Myers: I Have No Relevant Financial Relationships To Disclose Case/Program Description: Three patients presented for evaluation of wrist drop. Patient 1 was a 15-year-old boy who awoke with a wrist drop and numbness following surgical repair of a humerus fracture. Patient 2 was a 58-year-old woman who awoke with wrist drop associated with a bruise on her triceps and no history of trauma. Patient 3 was a 61-year-old man who awoke with a wrist drop following crutch use and recent weight loss. Setting: Outpatient EMG Clinic. Results: Patient 1 had reduced radial motor and sensory amplitudes on nerve conduction studies (NCS); Neuromuscular ultrasound (NMUS) revealed a surgical screw impinging on the nerve at the spiral groove. Patient 2 had normal radial NCS and reduced recruitment in the extensor digitorum communis; NMUS revealed increased hypoechogenicity and caliber of the radial nerve at the exit of the spiral groove in direct contact with a hematoma. Patient 3 had reduced amplitude of the radial motor response with a normal radial sensory response, NMUS showed increased nerve swelling at the spiral groove on ultrasound. Discussion: Radial neuropathy at the spiral groove (Saturday Night Palsy) can be a challenging diagnosis based on electrodiagnosis alone because mild lesions can result in normal nerve conduction studies and severe lesions result in non-localizing axon loss pathology. Additionally, fascicular sparing can lead to erroneous localization (such as in case 3 where the lesion is at the spiral groove, but sensory fibers were spared). NMUS also revealed radial nerve pathology in this case series that has not been described previously in the literature (non-traumatic hematoma in case 2). Conclusions: Neuromuscular ultrasound can be a powerful compliment to electrodiagnosis in localizing radial neuropathies and determining etiology. Level of Evidence: Level V

Poster 364: Sensorimotor Polyneuropathy in a Patient with Rare Type B Insulin Resistance and a History of Systemic Lupus Erythematosus: A Case Report

(binding and modulating) sustained on repeated testing. EMG study was repeated 3 weeks later and showed findings favoring a neuromuscular junction (NMJ) dysfunction with improvement noted in prior demyelinating findings. Setting: Tertiary care hospital. Results: Clinical and electrodiagnostic findings initially favored diagnosis of Miller Fisher variant of GBS. However, positive AchR antibodies on repeated testing and electrodiagnostic findings on follow up EMG favoring NMJ disorder, suggested co-existing Myasthenia Gravis. The patient was treated with several sessions of plasmapheresis, high dose steroids, IVIG, Rituximab, and Infliximab with eventual improvement in motor symptoms and respiratory status. Discussion: Nivolumab is an anti-programmed death-1-specific monoclonal antibody that may be used in the treatment of metastatic renal cell carcinoma. Neurologic side effects are rare but include cases of immune polyneuropathies, Guillain Barré syndrome, myasthenia gravis, and immune encephalitis among others. While there have been reported cases of Nivolumab associated GBS and Myasthenia Gravis separately, this would be the first to describe a patient who had findings of both neurologic conditions simultaneously. Conclusions: With the development of new approaches for cancer treatment with immunotherapeutic drugs, it is essential that neurologic immune-related adverse events are recognized and treated as soon as possible, as early treatment increases the odds of recovery. Level of Evidence: Level V

Poster 314 Amyotrophic Lateral Sclerosis Masquerading as Myelopathy: A Case Report

reduction in right lip inversion and decreased hypertrophy of left facial muscles. Asymmetry was evaluated with patient photographs before and after treatment. Long-term follow up demonstrated sustained functional improvements, requiring re-infiltration at 8 months. Discussion: Aside from the cosmetic and psychological impact, facial palsy may lead to functional problems such as lip biting experienced by this patient. We present the case of an off label use of botulinum toxin injections to reduce the pull from stronger contralateral muscles contributing to functional impairments in a patient with congenital facial palsy. Conclusions: Botulinum toxin type A injections may be useful in reducing functional impairments related to either a congenital or chronic acquired facial palsy, thus contributing to reduced disability. This may be an alternative to more complicated and costly surgical interventions. Level of Evidence: Level V

Poster 149 Diagnosis of an Ulnar Nerve Foreign Body by Ultrasound: A Case Report

Disclosures: Kathleen Bell: Consulting fees or other remuneration (payment) Avanir Pharmaceutical Objective: To examine gender differences in post-injury symptom reporting for adolescents enrolled in the ConTex study, a longitudinal concussion registry in North Texas. Design: Consecutive enrollment of clinical cohort using self-report. Setting: Four outpatient concussion or sports medicine clinics in North Texas. Participants: Subjects were 56 female and 47 male full-time students aged 13-19 years (M1⁄415.2, SD1⁄41.6) who consecutively presented 0-110 days (M1⁄417.7, SD1⁄420.0) after sports-related concussion. Interventions: Not applicable. Main Outcome Measures: Generalized Anxiety Disorders-7 (GAD-7), Patient Health Questionnaire (PHQ-9), and a Concussion Symptom Log. Results: Across 31 individual anxiety, depression, and concussion items examined, females tended to endorse symptoms somewhat more often, but only two items were significantly different by gender: 1) “Not being able to stop or control worrying” and 2) “Feeling bad about yourselfeor that you are a failure or have let yourself or your family down” (P1⁄4.024 and .046, respectively), with higher frequency endorsement by females (29% vs 11% and 20% vs 6%, respectively). No significant gender differences were found in total anxiety, depression or concussion symptom log scores (P>.05). Conclusions: Using global anxiety and depression self-report scores, we found no significant differences between the level of symptom reporting in females and males. However, females reported two items with greater frequency, suggesting the possibility of different psychological sequelae post sports concussion in female versus male adolescents. Level of Evidence: Level I

Poster 35 An Increased Incidence of Neuralgic Amyotrophy

Case/Program Description: The patient was diagnosed with gait and self-care deficits after bilateral transtibial amputations, partial right hand amputation, and left wrist disarticulation due to ischemic necrosis of all four extremities after vasopressor use. He started inpatient rehabilitation at a preceding institution, but was later transferred to our facility to work with the rehabilitation team to achieve the highest possible level of function and independence. Upper and lower extremity prosthetics were provided shortly after hospital admission. The patient received a cable-operated transradial prosthetic arm with two detachable hooks of varying strengths for different utilities. He also received a Quantum myoelectric prosthetic for his left arm. The patient received a myoelectric prosthetic for his partially amputated right hand. For his lower extremities he was provided two pairs of prosthetics. The first pair was provided to him at an outside hospital and consisted of patellar tendon bearing (PTB) sockets with fixed ankle joints. The second pair provided at our facility also had PTB sockets but a more dynamic ankle was provided to allow for improved mobility. Medical complications during the admission included osteomyelitis of his right hand, multiple left shoulder pathologies restricting therapy, and signs of adjustment disorder with labile mood and occasional suicidal ideations. Setting: Inpatient rehabilitation unit at a veterans’ hospital. Results: The patient steadily recovered during his admission and by the time of discharge he had showed marked improvement in his mobility, emotional status, ADL’s and overall independence. Discussion: Quadruple amputees often have multiple physical, behavioral, and social barriers which may hinder patient care, cause complications, and limit their ability to achieve functional goals. Conclusions: A multifaceted team approach and a literature review of similar complicated cases can be beneficial to maximize the functional potential of quadruple amputee patients. Level of Evidence: Level V

Poster 260 Atypical Course of an Anomalous Accessory Deep Peroneal Nerve: A Case Report

Participants: Patient with brachial plexopathy of non-dominant upper extremity, patient’s wife, a team of 5 seniors majoring in Mechanical Engineering with 1 member double majoring in fine arts, a nurse specialist in rehabilitation, an occupational therapist with expertise in assistive technology, and a physiatrist. Interventions: Face-to-face encounters supplemented by video conferences. SolidWorks computer program was used to create images of the various iterations. 3D printing was used to fabricate the parts to be assembled. Main Outcome Measures: Patient perception of ease of use. Results or Clinical Course: A novel combination of magnets and interlocking parts were created to make a simple and reliable means for bringing the two ends of the jacket or coat together to bring the zipper ends together. The two-piece system is small enough to carry in a pocket of a jacket or coat. Total expenditures to make the device were less than