Aetna considers selective peripheral denervation (Bertrand procedure) medically necessary for the treatment of members with severe spasmodic torticollis (cervical dystonia) when both of the following criteria are met:

• Current symptoms are disabling; and

• Member has failed an appropriate course of pharmacotherapies or has had adverse side effects from the medications or the member has developed resistance to botulinum toxin type A or type B.

Aetna considers selective peripheral denervation experimental and investigational for the treatment of members with severe spasmodic torticollis when criteria are not met because the value of this procedure in persons without disability or in persons who have not failed medical management is unproven.

See also CPB 0113 - Botulinum Toxin.

Spasmodic torticollis (cervical dystonia), or torticollis, is the most common of the focal dystonias.  It is a disorder in which neck muscles contract involuntarily, resulting in abnormal movements and posture of the head and neck.  In general, the term -- spasmodic torticollis (ST) -- is used to describe spasms in any direction: forward (anterocollis), backward (retrocollis), and sideway (torticollis).  The movement may be sustained or jerky.  Spasm in the muscles or pinching nerves in the neck can result in severe pain.  In this regard, cervical pain is seen in approximately 80 % of patients with ST.  Torticollis generally occurs in middle age; beginning slowly and usually reaching a plateau.  Approximately 10 to 20 % of individuals with this condition experience a spontaneous remission; however, the remission may not be permanent.

Since the cause of ST is unknown, there is currently no cure for this disorder.  Treatment is geared towards symptomatic relief.  Various medications are used in treating this condition.  Botox (botulinum toxin type A) injections have been demonstrated to improve both pain and head position in 70 to 80 % of patients with ST.  The toxin is injected into the 2 or 3 most functionally active muscles, most commonly the sternomastoid, spenius capitus or trapezius.

In very severe cases of disabling ST when pharmacotherapies including Botox injections have failed or the side effects are too severe, selective peripheral denervation may offer relief of symptoms.  Selective peripheral denervation is a procedure in which nerves are removed at the point where they enter the selected hyperactive muscles; while innervation to uninvolved muscles is maintained.  Studies have indicated that this procedure is useful in selected patients.  Positive response to prior botulinum toxin therapy appears to be a very good indicator of outcome following selective peripheral denervation.

A systematic evidence review of dystonias by the EFNS/MDS-ES Task Force (Albanese, et al., 2006) concluded: "Selective peripheral denervation is a safe procedure with infrequent and minimal side effects that is indicated exclusively in cervical dystonia. This procedure requires a specialized expertise."

Guidance from the National Institute for Clinical Excellence (2004) concluded:"Current evidence on the safety and efficacy of selective peripheral denervation for cervical dystonia appears adequate to support the use of this procedure provided that the normal arrangements are in place for consent, audit and clinical governance." The guidance stated that "patient selection for this procedure is important" and that "patients should be offered the procedure only when their disease has become refractory to best medical treatment." Standard medical treatments for cervical dystonia identified by NICE includes physiotherapy, drugs to reduce spasm, and injections of botulinum toxin. The NICE guidance said that selective peripheral denervation may be an alternative, especially for people who have not responded to other treatments.