The Spinal Accessory Nerve.
The spinal accessory nerve consists of two parts, an internal or accessory portion, and an external or spinal portion.
The accessory part forms the motor portion of the pneumogastric and is distributed to the pharyngeal and laryngeal muscles, lesions of which have been considered in lesions of the vagus.
Lesions of the spinal part may result in spasm or paralysis. Torticollis—wry neck—may be congenital, fixed wry-neck, or spasmodic, acquired torticollis. This may be due to injury at birth, or to some abnormal intra-uterine condition, and results in shortening and atrophy of the sterno-mastoid muscle. The right side is almost exclusively affected. The development of the face on the affected side is slower than that of its fellow, hence facial asymmetry results.
The symptoms are not usually noticed for several months, owing to shortness of the baby's neck.
Treatment.—This is surgical, tenectomy relieving the deformity.
Spasmodic Wry-neck.—This form may be either clonic or tonic or a combination of the two. Males are more frequently affected than females, and it usually occurs between the ages of thirty and fifty. When it occurs in females, it is usually found in those of a hysterical nature and under thirty years of age. There is generally a neurotic family history. Cold may be an exciting cause, especially in persons inclined to rheumatism.
Symptoms.—While spasm may be the first symptom, it is often preceded by a sharp neuralgic pain or one of a dull character, or it may be that a sense of stiffness is the first premonitory warn-The spasm often comes on gradually, involving the sterno-mastoid alone, or it may include the trapezius.
The occiput is rotated toward the shoulder of the affected side, while the chin is elevated and the face turned to the sound side. The facial nerve, as well as the brachial plexus, may become involved, giving rise to a combined spasm of the muscles supplied.
The spasm is usually in abeyance during sleep. Clonic spasms are apt to be more painful than tonic spasms, the latter exhibiting more fatigue of the muscles than actual pain.
Prognosis.—The disease is apt to be chronic, though, after months or years, it may cease to progress, and improvement begin. If recovery takes place, recurrences are frequent.
Treatment,—Where functional, the antispasmodics and anti-rheumatics should be given a thorough trial. Such remedies as gelsemium, passiflora, scutellaria, plantago major, hyoscyamus, and the bromids of the former class, and macrotys, bryonia, and rhamnus Californica of the latter. Where pain is intense, a hypodermic of morphia may be necessary to overcome the spasm and relieve the pain. Galvanism is sometimes useful, and nerve-stretching has afforded relief in some cases.
Paralysis of the Spinal Accessory Nerve.—The same causes may be active in affecting the muscles and nerve-trunk that were seen in lesions of the pneumogastric; namely, degenerations, morbid growths, meningitis, or toxemia.
In paralysis of the spinal portion there is atrophy of the sterno-mastoid on the affected side, impairing the power of rotating the head toward the opposite side, and partial paralysis of the trapezius, which interferes with lifting the arm. The shoulder drops, and the supra-clavicular depression is increased.
Where there is bilateral paralysis of the sterno-mastoid with atrophy, the head falls backward, but if the trapezii are affected the head falls forward.
Treatment.—The cause must be carefully sought for, and, when a removal is possible, a cure may be affected. If the lesion be nuclear, but little may be expected from. medication.
Where due to pressure, surgery may afford relief. Electricity promises well in some cases.