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Bishop, Allen T.

https://orcid.org/0000-0001-9856-6448

Mayo Clinic

Mayo Clinic

Citations 95

An intraneural ganglion cyst of the dorsal cutaneous branch of the ulnar nerve arising from the wrist: support for the articular origin. Illustrative case
O’Driscoll, Christopher J. L., Spinner, Robert J. , Amrami, Kimberly K. , O’Driscoll, Christopher J. L., Bishop, Allen T.

Journal of Neurosurgery: Case Lessons | March 17, 2025 | Volume: 9 | Issue: 11 | Pages: No page available

10.3171/case24569 Get It

BACKGROUND The articular theory of the formation of intraneural cysts has significant supporting evidence at common locations but has been less accepted at rarer sites. There have been only 5 cases in the literature documenting an intraneural ganglion cyst in the dorsal cutaneous branch of the ulnar nerve (DCBUN), with only 1 case documenting a joint connection. In this report, the authors present a second case with a proven joint connection in support of the articular theory. OBSERVATIONS The authors report the case of a 73-year-old man who developed a large intraneural ganglion cyst within the DCBUN along the palmar ulnar aspect of his left wrist. Magnetic resonance imaging demonstrated an articular connection to the distal radioulnar joint. During surgery, the intraneural ganglion cyst was resected and the articular branch was disconnected. The patient recovered and returned to work 4 weeks postoperatively. LESSONS This case further supports the articular theory as the explanation for intraneural ganglion cysts, even at unusual locations. https://thejns.org/doi/10.3171/CASE24569
Femoral Trochlea Osteochondral Autograft Transplant for Scaphoid Proximal Pole Nonunions
Lee, Ellen Y. , Bishop, Allen T., Bishop, Allen T. , Shin, Alexander Y.

Techniques in Hand & Upper Extremity Surgery | March 6, 2025 | Volume: 29 | Issue: 2 | Pages: No page available

10.1097/bth.0000000000000510 Get It

Small proximal pole scaphoid nonunions are challenging to treat. We describe a technique for replacing the proximal pole fragment with an osteochondral autograft transplant harvested from the ipsilateral femoral trochlea. This is indicated in nonunions where the proximal pole fragment is smaller than the scaphoid isthmus; the scapholunate ligament complex is intact on the distal fragment, and in nonunions without dorsal intercalated segment instability and radiocarpal arthritis. The osteochondral autograft transplant is press-fitted into the distal scaphoid and does not require implants for osteointegration. This provides an advantage during revision surgery of previously fixed proximal scaphoid fractures that are not united with an implant in situ.
Extensor Pollicis Longus Tendon Rupture With Concomitant Electrodiagnostic and MRI Findings of Posterior Interosseous Nerve Palsy
Lin, James S. , Kakar, Sanjeev , Shin, Alexander Y. , Bishop, Allen T. , Shin, Alexander Y , Kakar, Sanjeev , Bishop, Allen T

JBJS Case Connector | January 16, 2025 | Volume: 15 | Issue: 1 | Pages: No page available

10.2106/jbjs.cc.24.00344 Get It

Cases: Two patients with spontaneous loss of thumb interphalangeal joint extension were referred after history, electrodiagnostic, and/or magnetic resonance imaging (MRI) findings were felt to demonstrate a posterior interosseous nerve (PIN) palsy. Subsequent physical examination and additional directed studies suggested an alternative explanation: rupture of the extensor pollicis longus (EPL) tendon, subsequently confirmed at surgery. An extensor indicis proprius to EPL transfer restored thumb function. Conclusion: Electrodiagnostic and MRI changes consistent with diffuse PIN palsy may occur in the setting of EPL rupture. An accurate diagnosis of EPL dysfunction requires careful physical examination and confirmatory imaging. Further study of this previously unreported phenomenon is required.
Treatment Options for Coronal Plane Fractures of the Lunate in Kienböck Disease
Dittman, Lauren E. , Munaretto, Nicholas , Lenartowicz, Karina A. , Shin, Alexander Y. , Moran, Steven L. , Kakar, Sanjeev , Tagliero, Lauren E , Lenartowicz, Karina, Shin, Alexander Y , Bishop, Allen, Kakar, Sanjeev , Munaretto, Nicholas , Bishop, Allen T.

HAND | November 26, 2024 | Volume: 21 | Issue: 1 | Pages: 151-158

10.1177/15589447241298722 Get It

Background: The treatment for Kienböck disease varies widely based on the status of the lunate. To date, there is no consensus regarding the optimal treatment for patients with coronal plane fractures of the lunate, or Lichtman Stage IIIC. Therefore, the purpose of this study was to assess whether coronal plane fractures of the lunate in Kienböck disease healed after surgical intervention, and to determine the outcomes after surgical fixation of the lunate compared with treatment with salvage procedures. Methods: A retrospective review of 36 patients with Lichtman IIIC Kienböck disease was conducted. Patients were classified into lunate reconstruction (vascularized bone graft [VBG] or non-VBG) or salvage procedures (proximal row carpectomy [PRC] or limited fusion). Preoperative and postoperative visual analog scale (VAS) pain, range of motion, grip strength, and Mayo Wrist Score (MWS) were analyzed. Radiographs and computed tomographic scans were reviewed for Lichtman stage, fracture location, union, modified carpal height ratio, Stahl index, and radioscaphoid angle. Results: Thirteen patients underwent lunate reconstruction, 13 underwent limited fusion, and 10 underwent PRC. The overall union rate was 45% after lunate reconstruction, with average time to union of 7 months. There were no differences in union rates between VBG and non-VBG. All 3 groups experienced improvement in their postoperative grip strength and MWS. There were no statistically significant differences in preoperative to postoperative changes in clinical outcome measures between the 3 cohorts; however, when we compared lunate reconstruction with all patients who underwent salvage procedures (limited carpal fusion and PRC), we noted the latter had improved functional outcomes ( P = .019). Four patients (31%) in the reconstruction cohort and 2 patients (8%) in the limited carpal fusion group required reoperation at latest follow-up. Conclusions: Union rate of coronal plane fractures in Kienböck disease remains variable. While the proportion of patients requiring reoperation was higher in the reconstruction group, all groups of patients experienced improvement in their clinical outcomes, without a significant difference between cohorts.
Triceps-to-Biceps Tendon Transfer Technique for Restoration of Elbow Flexion in Adult Brachial Plexus Injury
Weber, Morgan B. , Townsley, Sarah, Spinner, Robert J. , Bishop, Allen T. , Shin, Alexander Y.

Techniques in Hand & Upper Extremity Surgery | July 12, 2024 | Volume: 28 | Issue: 4 | Pages: 214-223

10.1097/bth.0000000000000491 Get It

Restoration of elbow flexion is a priority in treating adult traumatic brachial plexus injuries. A tendon transfer is an ideal option for patients not candidates for reconstructive nerve surgery or free-functioning muscle transfer. For patients with a partial brachial plexus injury or a pan plexus injury with adequate recovered triceps function and loss of elbow flexion, a triceps-to-biceps tendon transfer is a nonmicrosurgical option to restore elbow flexion. The technique of triceps-to-biceps transfer in which the complete triceps tendon is transferred laterally, secured lateral to the radial tuberosity, and reinforced with suture to the biceps tendon is described.
Evaluating the Ability of Brachial Plexus-Injured Patients to Control an Externally Powered (Myoelectric) Hand Prosthesis
Lee, Ellen Y. , NELSON, A. WENDELL , Sampson, Brandon P. , Smither, F. Clay , Pulos, Nicholas , Bishop, Allen T. , Spinner, Robert J. , Shin, Alexander Y. , Shin, Alexander Y , Bishop, Allen T , Pulos, Nicholas

Journal of Bone and Joint Surgery | May 10, 2024 | Volume: 106 | Issue: 24 | Pages: 2375-2382

10.2106/jbjs.23.00938 Get It

Background: Restoration of hand function after traumatic brachial plexus injury (BPI) remains a formidable challenge. Traditional methods such as nerve or free muscle transfers yield suboptimal results. Advancements in myoelectric prostheses, characterized by novel signal acquisition and improved material technology, show promise in restoring functional grasp. This study evaluated the ability of adults with a BPI injury to control an externally powered prosthetic hand using nonintuitive signals, simulating the restoration of grasp with a myoelectric prosthesis. It also assessed the effectiveness of a comprehensive multidisciplinary evaluation in guiding treatment decisions. Methods: A multidisciplinary brachial plexus team assessed adults with compromised hand function due to BPI. The feasibility of amputation coupled with fitting of a myoelectric prosthesis for grasp reconstruction was evaluated. Participants' ability to control a virtual or model prosthetic hand using surface electromyography (EMG) as well as with contralateral shoulder motion-activated linear transducer signals was tested. The patient’s input and injury type, along with the information from the prosthetic evaluation, were used to determine the reconstructive plan. The study also reviewed the number of participants opting for amputation and a myoelectric prosthetic hand for grasp restoration, and a follow-up survey was conducted to assess the impact of the initial evaluation on decision-making. Results: Of 58 subjects evaluated, 47 (81%) had pan-plexus BPI and 42 (72%) received their initial assessment within 1 year post-injury. Forty-seven patients (81%) could control the virtual or model prosthetic hand using nonintuitive surface EMG signals, and all 58 could control it with contralateral uniscapular motion via a linear transducer and harness. Thirty patients (52%) chose and pursued amputation, and 20 (34%) actively used a myoelectric prosthesis for grasp. The initial evaluation was informative and beneficial for the majority of the patients, especially in demonstrating the functionality of the myoelectric prosthesis. Conclusions: The study indicates that adults with traumatic BPI can effectively operate a virtual or model myoelectric prosthesis using nonintuitive control signals. The simulation and multidisciplinary evaluation influenced informed treatment choices, with a high percentage of patients continuing to use the myoelectric prostheses post-amputation, highlighting its long-term acceptance and viability. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.
The role of vascularized bone grafting for scaphoid nonunions in adolescents
Israel, Jacqueline S. , Pulos, Nicholas , Pulos, Nicholas , Bishop, Allen T. , Shin, Alexander Y.

Journal of Hand Surgery (European Volume) | April 25, 2024 | Volume: 49 | Issue: 9 | Pages: 1157-1159

10.1177/17531934241247279 Get It

A total of 26 adolescent patients were treated for scaphoid nonunion with a vascularized bone graft from either the medial femoral condyle or dorsal distal radius. There was an 85% union incidence, improved carpal alignment and a low incidence of complications.
Injury and Biological Factors Impact Shoulder Function following Autogenous Grafting of Spinal Nerves for Pan–Brachial Plexus Reconstruction
Wu, Kitty Y. , Loosbrock, Michelle F., Spinner, Robert J. , Li, Neill Y. , Bishop, Allen T. , Shin, Alexander Y.

Plastic & Reconstructive Surgery | April 2, 2024 | Volume: 154 | Issue: 5 | Pages: 918e-927e

10.1097/prs.0000000000011270 Get It

Background: Shoulder function after spinal nerve grafting in pan–brachial plexus injuries (pan-BPI) is not well described. The authors evaluated shoulder abduction (ABD) and external rotation (ER) after spinal nerve grafting to the suprascapular nerve, axillary nerve, or posterior division of the upper trunk and determined patient characteristics, injury severity and characteristics, and nerve graft factors that influenced outcomes. Methods: A total of 362 patients undergoing pan-BPI reconstruction and spinal nerve grafting for shoulder reanimation in a single institution between 2001 and 2018 were reviewed. Patient demographics, Injury Severity Score (ISS), graft characteristics, strength, range of motion for shoulder ABD and ER, and patient-reported outcomes were recorded. Patients were divided into 3 groups based on recovery of shoulder function: no return, ABD only, and ABD and ER. Results: A total of 110 patients underwent spinal nerve grafting, with 41 meeting inclusion criteria. Seventeen (41.5%) had no return of shoulder function, 14 (34.1%) had ABD alone, and 10 (24.4%) had ABD and ER. Patients with recovery of both ABD and ER were significantly younger (18.6 ± 5.56 years), had lower body mass index (22.4 ± 4.0), and had a lower ISS (10.5 ± 6.24; P = 0.003). Multivariable analysis found that with increasing age (OR, 0.786; 95% CI, 0.576, 0.941) and ISS (OR, 0.820; 95% CI, 0.606, 0.979), odds for return of ABD and ER decreased significantly. Conclusions: In pan-BPI, 24.4% of patients demonstrated return of both ABD and ER after spinal nerve grafting to suprascapular nerve and either axillary nerve or posterior division of the upper trunk. Age, body mass index, and ISS were associated with poorer recovery of shoulder function. Careful patient selection and consideration of age, body mass index, and ISS may improve outcomes of spinal nerve grafting for shoulder reanimation. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.
The failed adult traumatic brachial plexus reconstruction
Lee, Ellen Y. , Spinner, Robert J. , Shin, Alexander Y. , Shin, Alexander Y , Pulos, Nicholas , Bishop, Allen T.

Journal of Hand Surgery (European Volume) | February 19, 2024 | Volume: 49 | Issue: 11 | Pages: 1298-1312

10.1177/17531934241231170 Get It

Traumatic adult brachial plexus injuries typically cause immediate loss of upper limb function. Timely multidisciplinary treatment in specialized centres often results in a useful helper arm. Both the patient and the surgical team can benefit from an open discussion to set realistic expectations. Surgical reconstruction is customized for each patient, considering their injury factors and functional objectives. Optimizing pain control, adherence to procedure indications and using meticulous surgical techniques help minimize the risk of failing to meet the patient’s goals. The need for potential alternative treatment(s) if the desired result is not achieved should be detailed before the initial reconstruction. This review discusses late treatment options, including tendon transfers, joint fusions, free functioning muscle transfers and prosthetics, for managing the failed primary reconstruction of the traumatic adult brachial plexus.
Clinical Predictors of C5 Spinal Nerve Viability in Pan−Brachial Plexus Injuries
Wu, Kitty Y. , Asserson, Derek B. , Loosbrock, Michelle F., Spinner, Robert J. , Bishop, Allen T. , Shin, Alexander Y.

Plastic & Reconstructive Surgery | July 4, 2023 | Volume: 153 | Issue: 6 | Pages: 1131e-1137e

10.1097/prs.0000000000010906 Get It

Background: In pan–brachial plexus injury, distinguishing between preganglionic and postganglionic injuries is crucial to reconstructive planning. This study aimed to identify preoperative factors that would accurately predict a reconstructible C5 spinal nerve. Methods: Patients with pan–brachial plexus injury from a single institution between 2001 and 2018 were reviewed. Patient demographics, clinical examination, diagnostic imaging, and electrodiagnostic results were recorded. C5 viability was determined based on supraclavicular exploration and intraoperative electrophysiologic testing. Univariate analysis identified significant factors for regression analysis. A multivariable parsimonious model was created using stepwise high-performance logistic regression. Results: A total of 311 patients (mean age, 29.9 years; 46 women and 265 men; mean Injury Severity Score, 17.2) were included. A total of 134 patients (43%) had a viable C5 nerve, and 50 patients (12%) had a viable C6 nerve. Intact C5 spinal nerve on computed tomographic (CT) myelogram (OR, 5.4), positive Tinel test (OR, 2.6), muscle strength greater than or equal to 4 (according to the modified British Medical Research Council scale) for the rhomboid (OR, 1.3) or greater than or equal to 4 for the serratus anterior (OR, 1.4), and rhomboid needle electromyography (OR, 1.8) were predictive of having a viable C5 spinal nerve. The multivariable parsimonious stepwise model (area under the curve, 0.77) included four factors: positive Tinel test, intact C5 spinal nerve on CT myelogram, hemidiaphragmatic elevation, and midcervical paraspinal fibrillations. Conclusions: In this cohort of pan–brachial plexus patients with major polytrauma, there was a 43% incidence of viable C5 spinal nerve. A positive Tinel test (OR, 2.1) and intact C5 spinal nerve on CT myelogram (OR, 4.9) predicted a viable C5 nerve. In contrast, hemidiaphragmatic elevation (OR, 3.1) and midcervical paraspinal fibrillations (OR, 2.92) predicted root avulsion. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.