Neuroplasticity following Nerve Transfer of the Anterior Interosseous Nerve for Proximal Ulnar Nerve Injuries

Round table discussion: the management of idiopathic cubital tunnel syndrome

Idiopathic cubital tunnel syndrome is the second most common neuropathy in the upper limb. Best evidence regarding the surgical management of this condition has evolved from anterior or submuscular transposition as the former reference standard, to in situ simple release. Differences of opinion remain regarding the timing of surgery, type of surgery and adjunctive surgery. Four surgeons with Level 5 expertise were asked to answer specific questions regarding this condition.

The Unpredictable Ulnar Nerve-Ulnar Nerve Entrapment from Anatomical, Pathophysiological, and Biopsychosocial Aspects

Peripheral nerves consist of delicate structures, including a rich microvascular system, that protect and nourish axons and associated Schwann cells. Nerves are sensitive to internal and external trauma, such as compression and stretching. Ulnar nerve entrapment, the second most prevalent nerve entrapment disorder after carpal tunnel syndrome, appears frequently at the elbow. Although often idiopathic, known risk factors, including obesity, smoking, diabetes, and vibration exposure, occur. It exists in all adult ages (mean age 40-50 years), but seldom affects individuals in their adolescence or younger. The patient population is heterogeneous with great co-morbidity, including other nerve entrapment disorders. Typical early symptoms are paresthesia and numbness in the ulnar fingers, followed by decreased sensory function and muscle weakness. Pre- and postoperative neuropathic pain is relatively common, independent of other symptom severity, with a risk for serious consequences. A multimodal treatment strategy is necessary. Mild to moderate symptoms are usually treated conservatively, while surgery is an option when conservative treatment fails or in severe cases. The decision to perform surgery might be difficult, and the outcome is unpredictable with the risk of complications. There is no consensus on the choice of surgical method, but simple decompression is relatively effective with a lower complication rate than transposition.

Supercharging of the ulnar nerve: clinical and neurophysiological assessment at 2 years for nine proximal injuries

LEVEL OF EVIDENCE

II.

Modern Treatment of Cubital Tunnel Syndrome: Evidence and Controversy

Cubital tunnel syndrome is the second most common peripheral mononeuropathy in the upper extremity. However, the diagnosis and treatment of cubital tunnel syndrome remains controversial without a standard algorithm. Although diagnosis can often be made from the patient's history and physical examination alone, electrodiagnostic studies, ultrasound, computed tomography (CT), and magnetic resonance image (MRI) can also be useful in diagnosing the disease and selecting the most appropriate treatment option. Treatment options include conservative nonoperative techniques as well as various surgical options, including in situ decompression with or without transposition, medial epicondylectomy, and nerve transfer in advanced disease. The purpose of this review is to summarize the most up-to-date literature regarding cubital tunnel syndrome and propose a treatment algorithm to provide clarity about the challenges of treating this complex patient population.

Reverse End-to-Side Transfer to Ulnar Motor Nerve: Evidence From Preclinical and Clinical Studies

The disappointing outcomes of conventional nerve repair or grafting procedures for proximal ulnar nerve injuries have led the scientific community to search for better alternatives. The pronator quadratus branch of the anterior interosseous nerve has been transferred to the distal ulnar motor branch in a reverse end-to-side fashion with encouraging results. This transfer is now becoming commonly used as an adjunct to cubital tunnel decompression in patients with compressive ulnar neuropathy, underscoring the need for this knowledge transfer to the neurosurgical community. However, the mechanism of recovery after these transfers is not understood completely. We have reviewed the existing preclinical and clinical literature relevant to this transfer to summarize the current level of understanding of the underlying mechanisms, define the indications for performing this transfer in the clinic, and identify the complications and best practices with respect to the operative technique. We have also attempted to identify the major deficiencies in our current level of understanding of the recovery process to propose directions for future research.

Neurosensory Re-education following Gender-affirming Phalloplasty: A Novel Treatment Protocol

Sensory nerve transfers are performed as part of phalloplasty surgery. Despite this, sensory re-education to rehabilitate these nerve transfers has not been employed. Additionally, little attention has been paid to the role of the central nervous system in experienced sensation following phalloplasty. The purpose of this article is to report on the development of a targeted rehabilitation protocol to integrate and optimize peripheral and central contributions to sensation following phalloplasty.

Methods

This neurosensory re-education protocol was constructed over four phases by a multi-disciplinary team (phalloplasty/peripheral nerve surgeon, reconstructive urologist, pelvic floor physiotherapists, nerve therapist, sex therapist, sexual medicine physician) and individuals with lived phalloplasty experience. The final protocol was approved by all team members and is supported here by qualitative narratives from people with lived phalloplasty experience.

Results

The protocol is built to follow each stage of phalloplasty surgery. In each stage, exercises are grouped into three core themes: visualization, tactile stimulation, and sexual/erogenous stimulation. Visualization exercises progress from static to dynamic. Tactile exercises start at simple touch and progress toward targeted sensory stimulation. Sexual stimulation focuses on developing erogenous sensation in the phallus that is separate from erogenous sensation in the natal clitoral tissue. By recommendation of individuals with phalloplasty, the protocol is now integrated into our center's phalloplasty care pathway for all individuals undergoing phalloplasty surgery.

Conclusion

We introduce a novel protocol targeting peripheral and central contributions to sensation to provide a tool to help optimize experienced sensation for transmasculine individuals undergoing phalloplasty.

Anterior Interosseous Nerve to Ulnar Nerve Transfer: A systematic review

Background

Objectives

Methods

Results

Conclusion