Acute motor-sensory axonal neuropathy after cervical spine surgery.

By London Spine
Related Articles

Acute motor-sensory axonal neuropathy after cervical spine surgery.

J Neurosurg Spine. 2012 Jul;17(1):82-5

Authors: Miscusi M, Currà A, Della Rocca C, Missori P, Petrozza V

Abstract
The authors report the case of a 55-year-old man who presented with acute motor-sensory axonal neuropathy (AMSAN), a variant of Guillain-Barré syndrome with a poor prognosis, immediately after surgery for resection of a cervical chondroma. A misdiagnosis of spinal cord shock due to an acute surgical or vascular postoperative complication was initially made in this patient. Nevertheless, there was continuous transient improvement that was followed by progressive worsening, and further investigation was necessary. The diagnosis of AMSAN, associated with acute colitis caused by Helicobacter pylori, was made based on neurophysiological examinations and colonoscopy. Interestingly, the patient also developed nephrotic syndrome, which was thought to be a further complication of the autoimmune reaction. Delayed administration of immunoglobulins (400 mg/kg/day), mesalazine (800 mg 3×/day), and meropenem (3 g/day) was used to treat the Helicobacter infection and the autoimmune reaction, leading to restoration of renal function and slight neurological improvement. The patient’s general condition and neurological status improved slightly, but he remained seriously disabled (Frankel Grade C). This case demonstrates that a new onset of neurological symptoms in the early postoperative period after spine surgery could be related to causes other than iatrogenic myelopathy, and that an early diagnosis can reduce neurological sequelae, leading to a better outcome.

PMID: 22559275 [PubMed – indexed for MEDLINE]

Pathological effects and motor response threshold changes following radiofrequency application at various distances from the L-5 nerve root: an experimental study.

By London Spine
Related Articles

Pathological effects and motor response threshold changes following radiofrequency application at various distances from the L-5 nerve root: an experimental study.

J Neurosurg Spine. 2011 Sep;15(3):285-91

Authors: Maarrawi J, Kobaiter-Maarrawi S, Ghanem I, Ali Y, Aftimos G, Okais N, Samaha E

Abstract
OBJECT: Radiofrequency (RF) ablation is a minimally invasive technique often used percutaneously in the treatment of many conditions such as spasticity, pain, and osteoid osteoma. The purpose of this study was to assess the value of motor response threshold (MRT) as an indirect indicator of the RF generator’s electrode to nerve distance, and to evaluate the effects of RF at various distances from a nervous structure.
METHODS: The L-5 nerve root was studied in 102 Sprague-Dawley rats (sham contralateral side). Motor response thresholds at 0, 2, 4, 5, and 6 mm from the nerve root were assessed before and after RF application for 2 minutes at 80° C on Days 0 and 7. Radiofrequency was applied 0, 2, 4, 5, and 6 mm away from L-5 and with the addition of interposed cortical bone. The effects of RF application on MRT were studied, and subsequent nerve injury was evaluated using light microscopy pathological examination.
RESULTS: There is a significant correlation between MRT and the distance between the electrode tip and L-5, with MRT less than 0.5 V when the electrode was in direct contact with the root. Electrical and pathological changes following RF application were more pronounced at 0 mm, with worsening seen on Day 7. Radiofrequency at 2 and 4 mm produced fewer electrical and histological deleterious effects on the nerve on Days 0 and 7, with an obvious improvement on Day 7. At 5 mm, electrical and histological abnormalities were minimal on Day 0 and were fully reversible on Day 7. At 6 mm and with interposed cortical bone, MRT and pathological findings were unchanged on Days 0 and 7.
CONCLUSIONS: The MRT proved to be a useful and reliable tool in decreasing nerve morbidity following RF ablation in animals and may be used in humans for the same purpose. It serves as an indirect indicator of the proximity of the RF generator’s electrode tip to any adjacent motor nervous structure. A minimum safe distance of 5 mm between the electrode tip and the nerve is required to avoid irreversible nerve injury, unless a bony wall is interposed between them, thus serving as a nerve shield. In medical conditions that require RF ablation of the nerve, such as spasticity and pain, the MRT must be lower than 0.5 V. When a nerve lesion is to be avoided such as in cases of osteoid osteoma, an MRT higher than 2.5 V is considered safe, reflecting a distance greater than 5 mm.

PMID: 21663402 [PubMed – indexed for MEDLINE]

Sensory and Motor Behavior Evidences Supporting the Usefulness of Conditioned Medium from Dental Pulp-Derived Stem Cells in Spinal Cord Injury in Rats.

By London Spine

Related Articles Sensory and Motor Behavior Evidences Supporting the Usefulness of Conditioned Medium from Dental Pulp-Derived Stem Cells in Spinal Cord Injury in Rats. Asian Spine J. 2018 Oct;12(5):785-793 Authors: Asadi-Golshan R, Razban V, Mirzaei E, Rahmanian A, Khajeh S, Mostafavi-Pour Z, Dehghani F Abstract STUDY DESIGN: Experimental animal study. PURPOSE: This study aimed to…

Motor impairments in an oxidative stress model and its correlation with cytological changes on rat striatum and prefrontal cortex

By London Spine

Exposure to ozone results in an increased production of free radicals which causes oxidative stress. The purpose of this study was to determine the effects of ozone exposure on motor behavior and its correlation with the cytology of the striatum and prefrontal cortex. Twenty-four male Wistar rats were exposed to 1 p.p.m. (parts per million)…