Search

Traumatic peripheral nerve injuries (PNI), present with symptoms ranging from pain to loss of motor and sensory function. Difficulties in intraoperative visual assessment of nerve functional status necessitate intraoperative nerve conduction studies (INCSs) by neurosurgeons and neurologists to determine the presence of functioning axons in the zone of a PNI. This process, also referred to as nerve "inching", uses a set of stimulating and recording electrode hooks to lift the injured nerve from the surrounding surgical field and to determine whether an electrical stimulus can travel through the zone of injury. However, confounding electrical signal artifacts can arise from the current workflow and electrode design, particularly from the mandatory lifting of the nerve, complicating the definitive assessment of nerve function and neurosurgical treatment decision-making. The objective of this study is to describe the design process and verification testing of our group's newly designed stimulating and recording electrodes that do not require the lifting or displacement of the injured nerve during INCSs. Ergonomic in vivo analysis of the device within a porcine model demonstrated successful intraoperative manipulation of the device, while quantitative nerve action potential (NAP) signal analysis with an ex vivo simulated "inching" procedure on healthy non-human primate nerve tissue demonstrated excellent reproducible recorded NAP fidelity and the absence of NAP signal artifacts at all points of recording. Lastly, electrode pullout force testing determined maximum forces of 0.43 N, 1.57 N, and 3.61 N required to remove the device from 2 mm, 5 mm, and 1 cm nerve models, respectively, which are well within established thresholds for nerve safety. These results suggest that these new electrodes can safely and successfully perform accurate PNI assessment without the presence of artifacts, with the potential to improve the INCS standard of care while remaining compatible with currently used neurosurgical technology, infrastructure, and clinical workflows. [ABSTRACT FROM AUTHOR]

The Seddon and Sunderland classifications have been used by physicians for peripheral nerve injury grading and treatment. While Seddon classification is simpler to follow and more relevant to electrophysiologists, the Sunderland grading is more often used by surgeons to decide when and how to intervene. With increasing availability of high‑resolution and high soft‑tissue contrast imaging provided by MR neurography, the surgical treatment can be guided following the above‑described grading systems. The article discusses peripheral nerve anatomy, pathophysiology of nerve injury, traditional grading systems for classifying the severity of nerve injury, and the role of MR neurography in this domain, with respective clinical and surgical correlations, as one follows the anatomic paths of various nerve injury grading systems. [ABSTRACT FROM AUTHOR]

Up to 10% of cervical spine surgeries are complicated by postoperative weakness. Although many patients recover with nonoperative management, some require surgery for restoration of function. To present the indications and outcomes of patients undergoing nerve transfers after developing weakness secondary to cervical spine decompression. A retrospective review of patients from 2 academic medical centers who underwent nerve transfer for C5–6 root injury after cervical spine surgery was performed. Of the 10 treated patients, 9 experienced recovery at last follow-up, demonstrating improvements in strength and motion in the affected muscles. Successful nerve transfers occurred between 3 and 8 months after the index spinal surgery and included spinal accessory nerve to suprascapular nerve, triceps branch to anterior division of the axillary nerve, and/or ulnar or median fascicles to motor branches of the musculocutaneous nerve. The unsuccessful patient underwent nerve transfer surgery approximately 11 months after the index operation and failed to obtain functional recovery. Patients who experience C5–6 weakness after cervical spine surgery should be evaluated and considered for nerve transfer surgery if they have continued severe functional deficits at 6 months postoperatively. Earlier referral for nerve transfer is associated with improved functional outcomes in this cohort. [ABSTRACT FROM AUTHOR]

The article discusses the retrospective chart review of patients who underwent operative treatment by Doctor Harvey Cushing at the Johns Hopkins Hospital between 1896 and 1912 for the illustration of the early use of peripheral nerve anastomoses for treating postpoliomyelitis paralysis. Cushing was unsuccessful in the multiple peripheral nerve anastomoses performed in a three-year-old girl for the restoration of her motor function.