Anatomical variations of the sternocleidomastoid muscle (SCM) have been observed to occupy multiple origins and insertion points and have supernumerary heads, sometimes varying in thickness. During routine dissection, a SCM was observed to have six distinct insertions that interface with the course of the superior nuchal line, ending at the midline, bilaterally. This variation was also seen to receive innervation from the accessory nerve as well as the great auricular nerve. To our knowledge, this variant of supernumerary insertions and nerve innervations has not yet been reported. These variants may pose as problematic during surgical approaches to the upper neck and occiput, and should thus be appreciated by the clinician. Herein we discuss the case report, possible embryological origins, and the clinical significance of the observed variant SCM.
Accessory Nerve ; Head ; Mastoid ; Neck

Ultrasound of cranial nerves is a novel subdomain of neuromuscular ultrasound (NMUS) which may provide additional value in the assessment of cranial nerves in different neuromuscular disorders. Whilst NMUS of peripheral nerves has been studied, NMUS of cranial nerves is considered in its initial stage of research, thus, there is a need to summarize the research results achieved to date. Detailed scanning protocols, which assist in mastery of the techniques, are briefly mentioned in the few reference textbooks available in the field. This review article focuses on ultrasound scanning techniques of the 4 accessible cranial nerves: optic, facial, vagus and spinal accessory nerves. The relevant literatures and potential future applications are discussed.
Accessory Nerve ; Cranial Nerves* ; Peripheral Nerves ; Ultrasonography*

To investigate the variations of the dorsal root of the first cervical nerve and its anastomosis with the spinal accessory nerve, a total of 74 anatomical dissections has been performed in 37 cases of Korean human fetus. The anastomotic connections between the dorsal roots and the spinal accessory nerve have fitted into five main types. The central course of the sensory fibers of the first cervical nerve and the neurosurgical significance of the variations have been discussed. Often the only pathway for the sensory fibers of the first cervical nerve to reach the spinal cord is through the rootlets of the spinal accessory nerve.
Accessory Nerve ; Fetus ; Humans ; Spinal Cord ; Spinal Nerve Roots*

OBJECTIVETo comprehend the anatomic characteristics and correlations between the accessory nerve and the phrenic nerve in the adult corpses.

METHODSThe bilateral accessory nerves, phrenic nerves, and their branches of 20 adult corpses (38 sides) were underwent exposure. The morphologic data of the accessory nerves and the phrenic nerves above clavicle were measured. In addition, the minimal and maximal distances from several points on the accessory nerve to the full length of the phrenic nerve above clavicle were measured. Then, the number of motor nerve fibers on different locations of the nerves utilizing the method of immunohistochemistry were counted and compared.

RESULTThe accessory nerves after sending out the sternocleido-mastoid muscular branches were similar in the morphologic data with the phrenic nerves. Meanwhile, the accessory nerve had a coiled appearance within this geometrical area. The possibly minimal distance between the accessory nerve and phrenic nerve was (3.19 ± 1.23) cm, and the possibly maximal distance between the starting point of accessory nerve and the end of the phrenic nerve above clavicle was (8.71 ± 0.75) cm.

CONCLUSIONSThe accessory nerve and the phrenic nerve are similar in the anatomic evidences and the number of motor nerve fibers. And the length of accessory nerve is sufficiently long to connect with phrenic nerve as needed. It is possible to suture them without strain directly.

Accessory Nerve ; anatomy & histology ; surgery ; Adult ; Female ; Humans ; Male ; Nerve Transfer ; Phrenic Nerve ; anatomy & histology ; surgery

BACKGROUND: Malignant peripheral nerve sheath tumors (MPNSTs), sarcomas originating from tissues of mesenchymal origin, are rare in patients without a history of neurofibromatosis. CASE REPORT: We report a case of an MPNST of the spinal accessory nerve, unassociated with neurofibromatosis, which metastasized to the brain. The tumor, originating in the intrasternomastoid segment of the spinal accessory nerve, was removed. Two years later, the patient presented with focal neurological deficits. Radiographic findings revealed a well-defined 2.2x2.2x2.2 cm, homogeneously enhancing mass in the left parieto-occipital region of the brain surrounded by significant vasogenic edema and mass effect, culminating in a 1-cm midline shift to the right. The mass was surgically removed. The patient had nearly complete recovery of vision, speech, and memory. CONCLUSIONS: To our knowledge, this is the first documented case of an MPNST arising from an extracranial segment of the spinal accessory nerve and metastasizing to the brain.
Accessory Nerve ; Brain ; Edema ; Humans ; Nerve Sheath Neoplasms ; Neurofibromatoses ; Sarcoma ; Vision, Ocular

We report here on a case of right side spasmodic torticollis (ST) that was refractory to botulinum toxin type A injection and medication.The patient finally underwent a selective ramisectomy with ipsilateral sternocleidomastoid muscle (SCM) resection, but the remaining symptoms slowly aggravated, and a contralateral left side SCM spasm began.As conservative therapy for reducing the spasmodic symptoms, accessory nerve block, upper cervical plexus block and stellate ganglion block were performed twice in a week.After 6 months, the spasmodic symptoms significantly decreased. The Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) decreased by more than 70%.After one year of serial intermittent local anesthetic blockade therapy, the patient became almost free from the original ST symptoms (TWSTRS = 1).Serial local anesthetic interventions for the ST patient may have a beneficial role on the pathological peripherocentral neural activity of the ST patient and can modulate motor-sensory integration in the patient.
Accessory Nerve ; Botulinum Toxins, Type A ; Cervical Plexus ; Humans ; Nerve Block* ; Spasm ; Stellate Ganglion ; Torticollis*

To determine the effects and its complications of ventral cervical and selective spinal accessory nerve rhizotomy in the spasmodic torticollis, 14 patients who had undergone surgery between 1989 and 1997 were reviewed retrospectively. In overall twenty four operations were performed. The ventral cervical rhizotomy with spinal accessory nerve rhizotomy were performed in nine patients and the ventral cervical rhizotomy without spinal accessory nerve rhizotomy were done in two patients. Five cases of sternocleidomastoid myotomy with or without peripheral accessory neurectomy, and the five cases of peripheral accessory neurectomy were also performed. In two patients, the selective peripheral denervations were performed. In overall thirteen patients(93%) showed improvement in their condition. Of the eleven patients with the ventral cervical rhizotomy and spinal accessory nerve rhizotomy, nine patients(82%) improved. Five patients suffered from dysphagia or dysphonia postoperatively for several months, but one patient is having more than two years. Of these six patients, five patients had undergone the bilateral upper cervical rhizotomy and bilateral accessory nerve rhizotomy. Therefore to reduce the postoperative dysphagia or dysphonia, the authors recommend to save the unilateral cervical ventral roots or unilateral accessory nerve root. The authors also stress that the selective peripheral denervation would be the choice of operation in cases with the spasmodic torticollis because of its effectiveness and rarity of complications.
Accessory Nerve ; Deglutition Disorders ; Denervation ; Dysphonia ; Humans ; Retrospective Studies ; Rhizotomy* ; Spinal Nerve Roots ; Torticollis*

Schwannomas of the jugular foramen, originating from the glossopharyngeal nerve, vagus and accessory nerve represent approximately 0.17-0.72% of all intracranial tumor, and consists of 1.4-2.9% of all intracranial schwannomas. The clinical presentation of these tumors varies significantly according to originated nerve and it's growth pattern. Magnetic resonance(MR) image and temporal bone computed tomography(CT) scan have a major role for diagnosis of such tumor. The treatment of choice is total resection whenever possible. Generally, suboccipital approach is sufficient for the removal of the tumor, but in case with large size, combination of resection of petrous part of temporal bone with or without transection of sigmoid sinus is may be necessory. We have recently experienced one case of giant jugular foramen schwannoma and postoperative fatal complication in a 34-year-old male who was treated with combined posterior petrous and suboccipital approach with transection of sigmoid sinus.
Accessory Nerve ; Adult ; Colon, Sigmoid ; Diagnosis ; Glossopharyngeal Nerve ; Humans ; Male ; Neurilemmoma* ; Temporal Bone

Spinal accessory nerve (SAN) injury mostly occurs during surgical procedures. SAN injury caused by manipulation therapy has been rarely reported. We present a rare case of SAN injury associated with manipulation therapy showing scapular winging and droopy shoulder. A 42-year-old woman visited our outpatient clinic complaining of pain and limited active range of motion (ROM) in right shoulder and scapular winging after manipulation therapy. Needle electromyography and nerve conduction study suggested SAN injury. Physical therapy (PT) three times a week for 2 weeks were prescribed. After a total of 6 sessions of PT and modality, the patient reported that the pain was gradually relieved during shoulder flexion and abduction with improved active ROM of shoulder. Over the course of 2 months follow-up, the patient reported almost recovered shoulder ROM and strength as before. She did not complain of shoulder pain any more.
Accessory Nerve Injuries* ; Accessory Nerve* ; Adult ; Ambulatory Care Facilities ; Electromyography ; Female ; Follow-Up Studies ; Humans ; Musculoskeletal Manipulations* ; Needles ; Neural Conduction ; Range of Motion, Articular ; Shoulder ; Shoulder Pain

A case of spasmodic torticollis in a 48-year-old man cured by micovascular decompression of the spinal accessory nerve with selective dorsal cervical rhizotomy of the first and second cervical nerves. The 11th nerve was compressed by the posterior inferior cerebellar artery originating from the vertebral artery at the C1 level. After intraoperative identification of each posterior rootlets of C1 and C2 nerves exclusively related with the involved sternocleidomastoid muscle(SCM) using the monopolar electric nerve stimulator, microvascular decompression with selective dorsal cervical rhizotomy was done using the Teflon felt and electrobipolar coagulator. The patient was significantly relieved from symptoms 1 week after operation.
Accessory Nerve ; Arteries ; Decompression ; Humans ; Microvascular Decompression Surgery* ; Middle Aged ; Polytetrafluoroethylene ; Rhizotomy ; Torticollis* ; Vertebral Artery