BACKGROUND Cervical spinal cord injuries result in a severe loss of function and independence. The primary goal for these patients is the restoration of hand function. Nerve transfers have recently become a powerful intervention to restore the ability to grasp and release objects. The supinator muscle, although a suboptimal tendon transfer donor, serves as an ideal distal nerve donor for reconstructive strategies of the hand. This transfer is also applicable to lower brachial plexus injuries. OBJECTIVE To describe the supinator to posterior interosseous nerve transfer with the goal of restoring finger extension following spinal cord or lower brachial plexus injury. METHODS Nerve branches to the supinator muscle are transferred to the posterior interosseous nerve supplying the finger extensor muscles in the forearm. RESULTS The supinator to posterior interosseous nerve transfer is effective in restoring finger extension following spinal cord or lower brachial plexus injury. CONCLUSION This procedure represents an optimal nerve transfer as the donor nerve is adjacent to the target nerve and its associated muscles. The supinator muscle is innervated by the C5-6 nerve roots and is often available in cases of cervical SCI and injuries of the lower brachial plexus. Additionally, supination function is retained by supination action of the biceps muscle.

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OBJECTIVE Bladder dysfunction after nerve injury has a variable presentation, and extent of injury determines whether the bladder is spastic or atonic. The authors have proposed a series of 3 nerve transfers for functional innervation of the detrusor muscle and external urethral sphincter, along with sensory innervation to the genital dermatome. These transfers are applicable to only cases with low spinal segment injuries (sacral nerve root function is lost) and largely preserved lumbar function. Transfer of the posterior branch of the obturator nerve to the vesical branch of the pelvic nerve provides a feasible mechanism for patients to initiate detrusor contraction by thigh adduction. External urethra innervation (motor and sensory) may be accomplished by transfer of the vastus medialis nerve to the pudendal nerve. The sensory component of the pudendal nerve to the genitalia may be further enhanced by transfer of the saphenous nerve (sensory) to the pudendal nerve. The main limitations of coapting the nerve donors to their intrapelvic targets are the bifurcation or arborization points of the parent nerve. To ensure that the donor nerves had sufficient length and diameter, the authors sought to measure these parameters. METHODS Twenty-six pelvic and anterior thigh regions were dissected in 13 female cadavers. After the graft and donor sites were clearly exposed and the branches identified, the donor nerves were cut at suitable distal sites and then moved into the pelvis for tensionless anastomosis. Diameters were measured with calipers. RESULTS The obturator nerve was bifurcated a mean ± SD (range) of 5.5 ± 1.7 (2.0–9.0) cm proximal to the entrance of the obturator foramen. In every cadaver, the authors were able to bring the posterior division of the obturator nerve to the vesical branch of the pelvic nerve (located internal to the ischial spine) in a tensionless manner with an excess obturator nerve length of 2.0 ± 1.2 (0.0–5.0) cm. The distance between the femoral nerve arborization and the anterior superior iliac spine was 9.3 ± 1.8 (6.5–15.0) cm, and the distance from the femoral arborization to the ischial spine was 12.9 ± 1.4 (10.0–16.0) cm. Diameters were similar between donor and recipient nerves. CONCLUSIONS The chosen donor nerves were long enough and of sufficient caliber for the proposed nerve transfers and tensionless anastomosis.

INTRODUCTION: Endovascular thrombectomy for select patients with anterior circulation stroke can be lifesaving if done in an appropriate therapeutic window. However, studies have demonstrated that failure of treatment ranges from 30-70%. Early determination of patients that are most likely to benefit from early revascularization is of pivotal importance.METHODS: We prospectively collected data from a high-volume stroke center for patients receiving MT for anterior circulation strokes. Outcomes evaluated included final Thrombolysis in Cerebral Infarction (TICI) score, the number of passes, complications from endovascular intervention, discharge NIHSS. Outcomes were clustered using a kmeans model after the number of optimal clusters were obtained using a silhouette algorithm. Uniform manifold projections (UMAP) were used to project the four outcomes into a 2-D space. Upon cluster determination, multivariate regression was used to determine predictors of cluster membership. Univariate comparisons leveraged chi-square and t-tests.RESULTS: 187 consecutive patients were selected for analysis. Included patients had an average age 69.96 (SD -15.14). Two distinct clusters were obtained, confirmed by the Silhouette model (1B). Cluster 2 was found to be associated with improved outcomes on univariate regression. Multivariate regression was used to identify predictors of cluster membership. ICA occlusion (OR = 7.63 (1.40 -48.6), p = 0.02). A onepoint increase in admission NIHSS was associated with an 11% increase in cluster 2 risk.CONCLUSIONS: In this study, we consolidate 4 outcomes using unsupervised machine learning. We found that cluster 2 patients did worse. We also demonstrated that ICA occlusion, Admission NIHSS, and smoking status were significantly associated with cluster 2 membership. Machine learning can be used to identify novel morphological characteristics of specific patient groups.