The Role of Muscle Selection in Cervical Dystonia

The choice of muscle selection for chemodenervation is probably the most difficult and complicated portion of the treatment of the patient with cervical dystonia. The choice of muscles should be made in conjunction with your physician. However, the more you know about the muscles of your neck that are being injected with a particular poison, the better off you may be.

There are several reasons for maximizing the injection medicine that you are given. First and foremost are that these medicines are poisons, and a general rule of thumb is to keep the dose as low as needed to produce the clinical effect. There is also an upper ceiling of how much or total quantity of medicine that can be given safely. The more medicine used the more the patient risks side-effects from the medication. One would like to get the most out of the injections. Therefore, it is my personal belief that EMG helps maximize the limited resources of our medications even further. The consideration for antibody formation would also want us to keep the dosage of medication to a minimum and the choice of muscle selection at an optimum. Finally, there is the consideration of cost of medication and injection procedures and if those can be kept to a minimum, so much the better.

Below is the choice of muscle selection for some of the more common and some uncommon muscle that I would consider for the various forms of torticollis.

Muscle Selection for Injection

Common Muscles

Sternocleidomastoid Splenius Capitis

Trapezius Semispinalis Capitis

Levator Scapulae Scalenus Medius

Uncommon Muscles

Splenius Cervicis Omohyoid

Scalenus Anterior Scalenus Posterior

Rectus Capitis Major Rectus Capitis Minor

Oblique Capitis Superior Oblique Capitis Inferior

Rhomboid Major Rhomboid Minor

 

 

Muscle Selection (Retrocollis)

First Choice

L / R Semispinalis capitis

L / R Semispinalis cervicis

L / R Splenius capitis

Second Choice

L / R Longissimus capitis

L / R Rectus Capitis Posterior Major

L / R Rectus Capitis Posterior Minor

 

 

Muscle Selection (Laterocollis)

First Choice

Ipsilateral Sternocleidomastoid

Ipsilateral Middle Scalene

Ipsilateral Trapezius

Second Choice

Ipsilateral Splenius Capitis

Ipsilateral Anterior / Posterior Scalene

Ipsilateral Levator Scapulae

Ipsilateral Rectus Capitis Major / Minor

Ipsilateral Oblique Capitis Superior / Inferior

 

 

Muscle Selection (Torticollis)

First Choice

Contralateral Sternocleidomastoid

Ipsilateral Splenius Capitis

Second Choice

Ipsilateral Splenius Cervicis

Ipsilateral Longissimus Capitis

Contralateral Semispinalis Cervicis

Ipsilateral Rectus Capitis Posterior Major

Ipsilateral Oblique Capitis Superior

 

 

Muscle Selection (Shoulder Elevation)

First Choice

Ipsilateral Trapezius

Ipsilateral Levator Scapulae

Second Choice

Ipsilateral Posterior Scalene

Ipsilateral Rhomboid Major

James Auberle M.D.