Prof. mamoun Kremli DR: Gehan Mohamed

 Recognize some Limb Anomalies  Amelia, Meromelia, Hemimelia  Polydactyly  Syndactyly  Amniotic band syndrome  Discuss Etiology

 Melia: from Greek: ”Limb”  Amelia: GK, A: Lack of..  Meromelia: Gk, meros: “part”: lack of part  Phocomelia:Gk, Phoco: “Seal”: like limb of Seal  Hemimelia: GK, Hemi: “Half”: lack of half of limb

 Limbs arise from small limb buds  Upper limb bud appear after 26 days  Lower limb bud appear after 28 days.

 Somatic lateral mesoderm →limb buds  (mesodermal core + ectodermal cap) →  elongated & fragmented → 3 portions

Wk 6  Terminal portions of limb buds form hand & foot plates  Digital rays in distal ends form fingers & toes (wk 8) (apoptosis of tissues in between)

 Limb anomalies Are -prevented: Amelia -Interrupted: Meromelia. Phocomelia, Hemimelia  Very early in the developing embryo:  Between days following fertilization

 Absence of one or more limbs

A. Environmental Factors 1. Teratogenic drugs ▪ e.g. Thalidiomide (was introduced as analgesic drug ) 2. Maternal Factors - Diabetes mellitus 3. Vascular accidents in uterus B. Genetics – 20% 1. Mutations in genes

 Partial absence of a limb or limbs

 Extremities resemble those of a seal.  Typically, hands and feet are present (may be normal or abnormal), but the intervening arms and legs are absent

 Poly: many, dactyl: digit (finger/toe)  Presence of more than normal number of fingers or toes  Rudimentary finger or toe, or  Fully developed extra digit(s)

18www.similima.com

 Most common congenital malformation of limbs  Incidence: 1 in

 % are familial  Non hereditary non syndromic  Few reports association with maternal smoking

 This type of mild syndactyly is found occasionally on the physical examination.  This is usually an isolated finding, and in this location, has no impact on function. 23www.similima.com

Watson S Arch Dis Child 2000;83:10-17 Copyright © BMJ Publishing Group Ltd & Royal College of Paediatrics and Child Health. All rights reserved.  Hand with transverse deficiency at the metacarpal level.

 At a different plane  At 90 o to other fingers  Opposition motion  50% of hand function

Watson S Arch Dis Child 2000;83:10-17 Copyright © BMJ Publishing Group Ltd & Royal College of Paediatrics and Child Health. All rights reserved.  Pollicization of the index finger to make a thumb FatherChild after surgery

Watson S Arch Dis Child 2000;83:10-17 Copyright © BMJ Publishing Group Ltd & Royal College of Paediatrics and Child Health. All rights reserved.  Hand with thumb and aplastic fingers.

 The constriction of appendages by amniotic bands may result in:  Restrictions of the growth around the digits, arms and legs  Constriction rings around the digits, arms and legs  the bands will partially constrict the blood flow in the affected appendage causing a deep groove in the baby's skin  Swelling of the extremities distal to the point of constriction (congenital lymphedema)  Amputation of digits, arms and legs (congenital amputation)

After surgery Before surgery

 Partial fibular hemimelia  Short leg

 Which is worse?  Why?

 Which is worse?  Why?  Which bone is more important for knee and ankle joint surfaces?

 Many congenital anomalies  Nomenclature:  Amelia  Phocomelia, meromelia  Hemimelia  Polydatyly, Syndactyly  Amniotic band syndrome

 Importance of thumb  50% of hand function  Tibial hemimelia Vs. Fibular hemimelia

 Causes od anomalies:  Teratogenic Drugs  Uterine problems ▪ Blood supply (vascular accidents)  Maternal factors ▪ Disease: Diabetes ▪ Smoking, Alcohol  Hereditary