Dysplasia: spondylo-epiphyseal (late)

[MIM 184 100, 271 600, 313 400, 208 230]

Very rare. Congenital osseous pathology of the vertebrae and the extremities of the long bones of the upper and lower limbs. The short stature appears around 4-10 years of age hence the 'late' appellation (spondyloepiphyseal dysplasia tarda).

The most frequent form is X-linked. Prevalence of 1/150,000 to 1/200,000, especially in boys caused by a mutation of the TRAPPC2 gene (also called SEDL) (Xp22.2-p22.1). This gene codes sedline, one of proteins of the TRAPP complex, that plays an important role in the transport of proteins between the intracellular organelles. The stature of girls carrying the gene is not short but they suffer from early osteoarthritis. The growth is normal until the end of childhood. Adult height is however greater than 150 cm.
Clinical appearance:

- short barrel-shaped trunk, short neck

- flattened vertebrae and thin intervertebral spaces

- dorsal kyphosis and lumbar lordosis, sometimes scoliosis

- hypoplastic odontoid process

- coxa vara

- early osteoarthritis of the hips, knees, shoulders

- rarely: association to a nephrotic syndrome

There are also forms of autosomal recessive transmission leading to progressive pseudorhumatoid facet arthropathy (PPAC, acronym for Progressive Pseudorheumatoid Arthropathy of Childhood). Its prevalence seems higher in the Maghreb and the Middle East regions. Caused by a mutation of the WISP3 gene (6q22). The first signs of the disease appear between 2 and 11 years of age: curvature of the legs (bowlegged), asymmetrical swelling of the proximal interphalangeal joints, painful limitation of movement. Vertebral involvement results in lumbar lordosis, dorsal kyphosis and scoliosis. XRay: images of spondyloepiphyseal dysplasia and osteoporosis.

Anesthetic implications:

check the atlo-axial joint stability; abnormal vertebrae can make a neuraxial block difficult to perform; a few case reports of laryngeal stenosis

EXPERT CONSENSUS for MANAGEMENT:

Surgical morbi-mortality is higher than in the normal population and the risk of anesthetic complications is very high: these patients must therefore be managed in facilities where care of those complications can be taken.

It is why :

- a full neurological examination is necessary before general or locoregional anesthesia

- imaging (MRI or CTscan) of the full spine is recommended

- a flexion/extension MRI of the cervical spine is necessary if there is any concern about its stability

- polysomnography, respiratory functional tests (restrictive or obstructive syndrome) and cardiac evaluation (echocardiography) must be considered before an anesthesia

- morphological and functional anomalies of the upper airway, a decrease in mobility of the cervical spine and bronchial airway anomalies increase the morbidity and mortality of anesthesia

- a sedative premedication can be administered before anesthesia

- for intubation, a videolaryngoscope and a intubating fiberscope must be immediately available

- tracheostomy can be extremely difficult in those patients, particularly in emergency; it is crucial to identify the position of the cricothyroid membrane (XRays, echography) before anesthesia

- extubation must be preferably done in the operating room; if this may not be the case, an experienced team must be present

- in patients in whom a fragility of the spinal cord is suspected (concept of spinal cord at risk : significant cyphosis, risk of hypotension, long lasting surgery, difficult surgical positioning), neurological monitoring must be done during the whole procedure, and it is better to avoid epidural anesthesia

Reference:
White KK, Bompadre V, Goldberg MJ, Bober MB, Cho T-J et al.
Best practices in peri-operative management of patients with skeletal dysplasias.
Am J Med Genet 2017 ; 173A : 2584-95

References :

- de Boer HD, Hemelaar A, van Dongen R, Gielen MJM.
Successful epidural anaesthesia for Caesarean section in a patient with spondyloepiphyseal dysplasia.
Br J Anaesth 2001; 86: 133-4.

Updated: December 2017