Definition
Radial hemimelia
- longitudinal failure of formation of parts along radial border / preaxial border
Incidence
1:100 000
4 x Ulna Club Hand
Bilateral 50%
Associations
Scaphoid & trapezium absent in 50% cases
Thumb absent in 80%
VACTERAL
Vertebral segmentation deficiencies
Anal atresia
Cardiac
Tracheoesophageal fistula
Endocrine including Fanconi's anaemia
Renal abnormalities
Radial ray deficiencies atresia
Limb - CTEV, radial club hand
Syndromes
Holt-Oram Syndrome
- ASD & RCH
Fanconi
- anaemia & RCH (pancytopenia)
TAR syndrome
- thrombocytopenia absent radius
Bayne Classification
1. Short distal radius
- distal radial epiphysis present but delayed in appearance
2. Hypoplastic radius
- delayed proximal & distal radial epiphyses appearance
- moderate shortening of the radius & thickening of the ulna
3. Partial absence of radius
- usually distal third absent
- carpus unsupported & radially deviated
4. Total absence of radius
- most common type
Pathology
All pre-axial structures may be affected
- forearm is radially bowed
- deviated in radial & volar direction
- progresses with growth
Ulna is bowed & short by 25%
Carpus attached to ulna by fibrous tissue or small synovial joint
There are also abnormalities of finger joints most marked in radial digits
Median nerve
- is thickened as carries sensation for radial nerve as well
- it is located deep to deep fascia on radial border of forearm
- at risk from surgery
Radial artery can be absent
Clinical
Radial & palmar flexed hand
- forearm is short (50-70%) & radially deviated
- thumb absent / deformed / almost normal thumb
25% have significant elbow extension contracture
- radial deviation may allow hand to mouth
- imperative this function is not disturbed
NHx
Worse than ulna club hand as tend to radially deviate
- OT may not prevent re-deformity
- if occurs wrist fusion at maturity
Management
1. Splinting & stretching from birth
- prevent excessive radial deviation
2. Centralisation procedure
Concept
- centralising carpus over ulna
- soft tissue release at 1 - 2 years
- maintain with tendon transfers
- transfer ECRL to ECRB
Prerequisites
- lack of hand to mouth function is a contraindication to surgery
- elbow mobility is prerequisite for centralisation
3. Management of hypoplastic thumb