Spasmodic torticollis is an adult onset focal or segmental dystonia. It is characterised by stereotype posture having a variable combination of neck flexion, extension, rotation and tilting. Each patient has a characteristic dystonic posturing. This dystonic posture is present at rest, worsen with action or stress, and improve or resolve completely during sleep. Torticollis is most commonly observed, in mid-adult life with the big incidence being between ages of 30 and 40 years. Initially Torticollis begins with a feel of tension in the neck muscles for months before the manifestation of dystonia. This is followed by intermittent posturing of the neck with head turning. Over a period of time this becomes constant and fixed, only abating during sleep. Symptoms may progress rapidly over several weeks or gradually over several years until a plateau is typically reached 3 to 5 years after the initial manifestation. Though temporary, spontaneous remission of Torticollis have been known, permanent remission is almost unusual.
The non-operative treatment for spasmodic torticollis includes physiotherapy, cervical brace and anticholinergics like Trihexphenidyl Hydrochloride, Anti-depressants, and muscle relaxants. The most therapeutic intervention is either botulinum toxin injection or surgery. Botulinum toxin injection is given in the neck muscles to denervate the select group of muscles to relieve muscle spasm. However this relief is temporary and recurrence is noted after three months and injection has to be repeated. Other focal dystonias affect specific body parts, but sometimes patients may suffer from more than one type of focal dystonia. These typically attack at mid life (40s to 50s).
Torticollis Surgery Procedure :
If botulinum toxin fails in the treatment of cervical dystonia, selective peripheral denervation is now accepted as the best surgical option. It is indicated in patients with cervical dystonia (Spasmodic Torticollis) who do not achieve adequate response with medical treatment or repeated botulinum injections. It is indicated in non responders to botulinum injections. Overall, about one to two-thirds of patients achieve useful long-term improvement. In this procedure, nerves supplying the affected muscles of the neck are selectively cut. In those patients who have symptoms like blepharospasms and laryngeal spasm in addition to cervical dystonia, peripheral denervation is not done and in these patients deep brain stimulation is done.
Skin incision for peripheral denervation.
In peripheral denervation for torticollis, a small incision is given at back of neck as shown in figure. Nerves outside the spinal canal, which are going to the affected muscles are first identified and stimulated under Neurophysiologic guidance and then they are cut. One of the muscle which is responsible for torticollis is sternocleidomastoid in the neck. So, one more small incision is taken in neck and nerve going to this muscle is selectively cut. Similarly the nerve supplying the muscle which is responsible for elevation of shoulder in torticollis is selectively cut. As the whole procedure is done under Neurophysiological monitoring, the results are extremely good.
The total duration of hospital stay is 6-7 days.
After selective peripheral denervation for spasmodic torticollis, it is very important that patients do posture exercises to regain a sense of midline, and to improve the range of movement. Although a denervation procedure for torticollis is not a curative treatment the over-all improvement of the symptoms is generally 80–90%.