Phocomelia syndrome

Overview

Phocomelia syndrome:- Phocomelia is a congenital disorder involving the limbs (dysmelia). An individual exhibiting phocomelia may be referred to as a phocomelus.

Symptoms

Typically the symptoms of phocomelia syndrome are undeveloped limbs and absent pelvic bones; however, various abnormalities can occur to the limbs and bones.[17] Usually the upper limbs are not fully formed and sections of the “hands and arms may be missing.”[18] Short arm bones, fused fingers, and missing thumbs will often occur. Legs and feet are also affected similarly to that of the arms in hands. Individuals with phocomelia will often experience missing thigh bones, and the hands or feet may be of an unordinary petite size or appear as stumps due to their close “attachment to the body.”[19] According to NORD, individuals carrying phocomelia syndrome will generally show symptoms of growth retardation previous to and after birth. The syndrome can also cause mental deficiencies in infants. Infants born with phocomelia will normally have a petite head with “sparse hair” that may appear “silvery-blonde.”[20] Hemangioma, the abnormal buildup of blood vessels, will possibly develop around the facial area at birth as and the eyes will be set distantly apart due to hypertelorism. The pigment of the eyes will be a bluish white.[21] Phocomelia can also cause: an undeveloped nose with slender nostrils, disfigured ears, irregularly petite jaws [also known as micrognathia], and a cleft lip with cleft palate.[22] According to NORD, severe symptoms of phocomelia include: * A fissure of the skull and a projecting brain known as (encephalocele) * An accumulation of spinal fluid under the skull also known as drocephalus; causing vomiting and migraines * An abnormally shaped uterus (bicornate) * Inability to clot blood efficiently due to a low amount of platelets running through the blood * Malformations in the kidney and heart * Shortened neck * Abnormalities in the urethra Thalidomide syndrome symptoms Eyesight limitation due to phocomelia. When an individual inherits phocomelia due to drugs or pharmaceuticals, it is known as thalidomide syndrome. The symptoms of thalidomide syndrome are defined by absent or shortened limbs; causing flipper hands and feet. According to Anthony J Perri III, and Sylvia Hsu they can additionally receive: * Palsy disorder of the face * Ear and eye abnormalities; resulting in limited/complete loss of hearing or sight * Gastrointestinal and genitourinary tract disorders * Ingrown genitalia * Undeveloped/missing lungs * Distorted digestive tract, heart, kidney The infants that were exposed to thalidomide during development phases have a 40% chance of survival.[23] The McMredie-McBride hypothesis explains that the limbs of the infants become malformed as a result to the thalidomide harming the neural tissue—simply because the neural tissue has such a large impact on formation and development of the limbs.[24]

Causes

The condition may be inherited or occurs sporadically. It is also connected with prenatal exposure to the anti-nausea drug thalidomide. In Holt-Oram syndrome, the most severe forms manifest with phocomelia with rudimentary limbs.

Treatment

Prosthesis is a synthetic alternative for missing limbs, teeth, hearts, and various other body parts. Advances in prosthetic limbs have increased greatly during the twentieth century. The use of new materials such as: modern plastics, complex procedures, and better pigments have created lighter in weight and more realistic looking artificial limbs. With the advancement of myoelectric prosthetic limbs, patients are able to move their limbs without the use of cords or other devices. The myoelectric limbs can detect electric signals from the nervous system and muscles. They were first used on adults, but now they are being fitted to children.[25] Patients that receive a loss of limbs due to phocomelia are typically treated with prosthetics. Infants at the age of 6 months are recommended to have a prosthetic mitten fitted to them; enabling them to get used to the prosthesis. A hook will be added when the child reaches the age of 2 years. Eventually the patient may receive a myoelectric prosthetic limb. Patients are treated in this way due to: the lack of understanding at a young age, the absence of necessary tissues and bones to hold the prosthesis together, and deficiency of sensory reaction from the patient.[26] Other surgical alternatives relating to phocomelia include: * Metacarpal transposition of the hand from the center to the edge * Skeletal distraction techniques * Bone distraction methods * On-top plasty * Nonvascularized phalangeal transfer from the foot * Nonvascularized bone graft * Vascularized toe-to-thumb transfers These surgical alternatives are made difficult due to the non-existent nerves, bones, tendons, and related structures