As of 2007, only about 100 cases had been reported in medical literature.[6]
Signs and symptoms
The symptoms of Freeman–Sheldon syndrome include drooping of the upper eyelids, strabismus, low-set ears, a long philtrum, gradual hearing loss, scoliosis and walking difficulties. Gastroesophageal reflux has been noted during infancy, but usually improves with age. The tongue may be small, and the limited movement of the soft palate may cause nasal speech. Often there is an H- or Y-shaped dimpling of the skin over the chin.[citation needed]
Cause
FSS is caused by genetic changes. Krakowiak et al. (1998) mapped the distal arthrogryposis multiplex congenita (DA2B; MIM #601680) gene, a syndrome very similar in phenotypic expression to classic FSS, to 11p15.5-pter.[7][8] Other mutations have been found as well.[9][10] In FSS, inheritance may be either autosomal dominant, most often demonstrated.[11][12][13] or autosomal recessive (MIM 277720).[14][15][16][17] Alves and Azevedo (1977) note most reported cases of DA2A have been identified as new allelic variation.[18] Toydemir et al. (2006) showed that mutations in embryonic myosin heavy chain 3 (MYH3; MIM *160270), at 17p-13.1-pter, caused classic FSS phenotype, in their screening of 28 (21 sporadic and 7 familial) probands with distal arthrogryposis type 2A.[19][20] In 20 patients (12 and 8 probands, respectively), missense mutations (R672H; MIM *160270.0001 and R672C; MIM *160270.0002) caused substitution of arg672, an embryonic myosin residue retained post-embryonically.[19][20][20] Of the remaining 6 patients in whom they found mutations, 3 had missense private de novo (E498G; MIM *160270.0006 and Y583S) or familial mutations (V825D; MIM *160270.0004); 3 other patients with sporadic expression had de novo mutations (T178I; MIM *160270.0003), which was also found in DA2B; 2 patients had no recognized mutations.[19][20]
Diagnosis
Freeman–Sheldon syndrome is a type of distal arthrogryposis, related to distal arthrogryposis type 1 (DA1).[21] In 1996, more strict criteria for the diagnosis of Freeman–Sheldon syndrome were drawn up, assigning Freeman–Sheldon syndrome as distal arthrogryposis type 2A (DA2A).[3]
On the whole, DA1 is the least severe; DA2B is more severe with additional features that respond less favourably to therapy. DA2A (Freeman–Sheldon syndrome) is the most severe of the three, with more abnormalities and greater resistance to therapy.[3]
In March 2006, Stevenson et al. published strict diagnostic criteria for distal arthrogryposis type 2A (DA2A) or Freeman–Sheldon syndrome. These included two or more features of distal arthrogryposis: microstomia, whistling-face, nasolabial creases, and 'H-shaped' chin dimple.[2]
Management
Surgical and anesthetic considerations
Patients must have early consultation with craniofacial and orthopaedicsurgeons, when craniofacial,[23][24][25]clubfoot,[26] or hand correction[27][28][29][30] is indicated to improve function or aesthetics. Operative measures should be pursued cautiously, with avoidance of radical measures and careful consideration of the abnormal muscle physiology in Freeman–Sheldon syndrome. Unfortunately, many surgical procedures have suboptimal outcomes, secondary to the myopathy of the syndrome.[citation needed]
When operative measures are to be undertaken, they should be planned for as early in life as is feasible, in consideration of the tendency for fragile health. Early interventions hold the possibility to minimise developmental delays and negate the necessity of relearning basic functions.[citation needed]
General health maintenance should be the therapeutic emphasis in Freeman–Sheldon syndrome. The focus is on limiting exposure to infectious diseases because the musculoskeletal abnormalities make recovery from routine infections much more difficult in FSS. Pneumonitis and bronchitis often follow seemingly mild upper respiratory tract infections. Though respiratory challenges and complications faced by a patient with FSS can be numerous, the syndrome's primary involvement is limited to the musculoskeletal systems, and satisfactory quality and length of life can be expected with proper care.[citation needed]
Prognosis
There are little data on prognosis. Rarely, some patients have died in infancy from respiratory failure; otherwise, life expectancy is considered to be normal.[citation needed]
Epidemiology
By 1990, 65 patients had been reported in the literature, with no sex or ethnic preference notable.[39] Some individuals present with minimal malformation; rarely patients have died during infancy as a result of severe central nervous system involvement[40] or respiratory complications.[41] Several syndromes are related to the Freeman–Sheldon syndrome spectrum, but more information is required before undertaking such nosological delineation.[42][43][44]
Research directions
One research priority is to determine the role and nature of malignant hyperthermia in FSS. Such knowledge would benefit possible surgical candidates and the anaesthesiology and surgical teams who would care for them. MH may also be triggered by stress in patients with muscular dystrophies.[45] Much more research is warranted to evaluate this apparent relationship of idiopathic hyperpyrexia, MH, and stress. Further research is wanted to determine epidemiology of psychopathology in FSS and refine therapy protocols.[citation needed]
^Hall JG, Reed SD, Greene G (February 1982). "The distal arthrogryposes: delineation of new entities—review and nosologic discussion". Am. J. Med. Genet. 11 (2): 185–239. doi:10.1002/ajmg.1320110208. PMID7039311.
^Vaitiekaitis AS, Hornstein L, Neale HW (September 1979). "A new surgical procedure for correction of lip deformity in cranio-carpo-tarsal dysplasia (whistling face syndrome)". J Oral Surg. 37 (9): 669–72. PMID288890.
^Nara T (July 1981). "Reconstruction of an upper lip and the coloboma in the nasal ala accompanying with Freeman-Sheldon syndrome". Nippon Geka Hokan. 50 (4): 626–32. PMID7316645.
^Ferreira LM, Minami E, Andrews Jde M (April 1994). "Freeman-Sheldon syndrome: surgical correction of microstomia". Br J Plast Surg. 47 (3): 201–2. doi:10.1016/0007-1226(94)90056-6. PMID8193861.
^Malkawi H, Tarawneh M (July 1983). "The whistling face syndrome, or craniocarpotarsal dysplasia. Report of two cases in a father and son and review of the literature". J Pediatr Orthop. 3 (3): 364–9. doi:10.1097/01241398-198307000-00017. PMID6874936. S2CID22025528.
^Call WH, Strickland JW (March 1981). "Functional hand reconstruction in the whistling-face syndrome". J Hand Surg Am. 6 (2): 148–51. doi:10.1016/s0363-5023(81)80168-2. PMID7229290.
^Martini AK, Banniza von Bazan U (1983). "[Hand deformities in Freeman-Sheldon syndrome and their surgical treatment]". Z Orthop Ihre Grenzgeb (in German). 121 (5): 623–9. doi:10.1055/s-2008-1053288. PMID6649810.
^Martini AK, Banniza von Bazan U (December 1982). "[Surgical treatment of the hand deformity in Freeman-Sheldon syndrome]". Handchir Mikrochir Plast Chir (in German). 14 (4): 210–2. PMID6763591.
^Wenner SM, Shalvoy RM (November 1989). "Two-stage correction of thumb adduction contracture in Freeman-Sheldon syndrome (craniocarpotarsal dysplasia)". J Hand Surg Am. 14 (6): 937–40. doi:10.1016/S0363-5023(89)80040-1. PMID2584652.
^Aldinger G, Eulert J (1983). "[The Freeman-Sheldon Syndrome]". Z Orthop Ihre Grenzgeb (in German). 121 (5): 630–3. doi:10.1055/s-2008-1053289. PMID6649811.
^Yamamoto S, Osuga T, Okada M, et al. (1994). "[Anesthetic management of a patient with Freeman-Sheldon syndrome]". Masui (in Japanese). 43 (11): 1748–53. PMID7861610.
^Sobrado CG, Ribera M, Martí M, Erdocia J, Rodríguez R (1994). "[Freeman-Sheldon syndrome: generalized muscular rigidity after anesthetic induction]". Rev Esp Anestesiol Reanim (in Spanish). 41 (3): 182–4. PMID8059048.
^Namiki M, Kawamata T, Yamakage M, Matsuno A, Namiki A (2000). "[Anesthetic management of a patient with Freeman-Sheldon syndrome]". Masui (in Japanese). 49 (8): 901–2. PMID10998888.
^Rao SS, Chary R, Karan S (March 1979). "Freeman Sheldon syndrome in a newborn (whistling face)--a case report". Indian Pediatr. 16 (3): 291–2. PMID110675.
^Träger D (1987). "[Cranio-carpo-tarsal dysplasia syndrome (Freeman-Sheldon syndrome, whistling face syndrome)]". Z Orthop Ihre Grenzgeb (in German). 125 (1): 106–7. doi:10.1055/s-2008-1039687. PMID3577337.
^Simosa V, Penchaszadeh VB, Bustos T (February 1989). "A new syndrome with distinct facial and auricular malformations and dominant inheritance". Am. J. Med. Genet. 32 (2): 184–6. doi:10.1002/ajmg.1320320209. PMID2929657.