Facio-scapulo-humeral type muscular dystrophy
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(Facio-scapulo-humeral dystrophy, Landouzy-Dejerine myopathy)
Prevalence: 1/20.000. It is the third most common muscle disease. Histology : picture of muscular dystrophy : muscle fibres of different sizes, with zones of necrosis replaced by fibrosis and fat).
From the genetic point of view, there are:
The importance of muscular involvement is highly variable and it is estimated that approximately 30 % of patients genetically affected have no or only very few clinical signs (mosaicism?).
Two main clinical presentations are described:
- congenital form or infantile (the face is affected before the age of 5 years, the shoulders and the pelvis before the age of 10 years): the muscular involvement is symmetrical with facial weakness and eversion of the lips (like the mouth of a tapir); hyperlordosis; development of scoliosis
- usual form: the muscle involvement is asymmetric ; onset during the adolescence, with fixed facies, non-occlusion of the eyelids during sleep (risk of keratitis and conjunctivitis), chewing difficulties; the involvement of the shoulder girdle (but the deltoid muscle is often spared) is catastrophic: the shoulder blades are protruding especially during abduction of the arms; the lower limbs are affected later (difficult walking, steppage); protruding abdomen because of weakness of the parietal muscles; hyperlordosis.
A third form without facial involvement [MIM 600 416] has been described in some families: this could be a variant.
In general, there is no impairment of respiratory, bulbar or extraocular muscles.
Damage to the retina (Coats disease: retinopathy with retinal exudates) and/or to the cochlea (sensorineural deafness) is common. A few cases of supraventricular paroxysmal tachycardia and hypertrophic cardiomyopathy have been reported.
Evolution is gradual and very slow: about 20 % of patients become wheelchair-bound and less than 5 % end up needing ventilatory assistance during sleep.
Anesthetic implications:
- preoperative: ECG: in case of anomaly, ask for an echocardiogram
- monitoring: to monitor the curarization, use preferably non affected muscles and check the TOF before administering any muscle relaxant; check if the patient can perform the head lift manoeuvre
- muscle relaxants : avoid succinylcholine as for any myopathy; it seems that the response to atracurium and vecuronium is normal but of shorter duration. Sugammadex has been successfully used to antagonize rocuronium
- halogenated agents: there is no risk of malignant hyperthermia; histologically it is a muscular dystrophy similar to Duchenne’s disease but not a dystrophinopathy: exposure to halogenated agents could potentially cause anesthesia-induced rhabdomyolysis but a few cases of uneventful use of enflurane and sevoflurane have been reported
- the combination of remimazolam and remifentanil has been used successfully
- regional anesthesia: hyperlordosis can make the realisation of a neuraxial block difficult; for peripheral blocks, dystrophy and muscle atrophy can change the echogenicity of the muscles.
References :
- Gurnaney H, Brown A, Litman RS.
Malignant hyperthermia and muscular dystrophies.
Anesth Analg 2009; 19:1043-8.
- Dresner DL, Ali HH.
Anaesthetic management of a patient with facioscapulohumeral muscular dystrophy.
Br J Anaesth 1989; 62: 331-4.
Updated: October 2023