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- G = Sonic hedgehog gene with abnormality in ZPA axis
- E = Resulting with short or missing fibula
- I = No inheritance pattern
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- Shortening (more from tibia), Hypoplasia, absent lateral rays
- I suspect this is Fibula hemimelia, would like to go on to take further Hx, PE, Invx
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- UL - ulnar club hand with missing ulnar digits (ulna bowing)
- Femur - shortened due to PFFD, Trendlenberg due to Coxa vara
- Knee - laxity (ACL deficiency), patellar instability, valgus knee (LFC hypoplasia ➔ ACL deficient)
- Tibia - Anteromedial bowing and dimpling
- Ankle - ROM stiff due to ball and socket, tight TA
- Foot - absent lateral rays, pes planus (tarsal coalition ➔ ankle remodels into ball and socket), equinovalgus foot (can be severe)
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- XR of hip - coxa vara, PFFD
- XR of knee - patella dislocated, tibia spines under-developed
- XR of tibia - anteromedial bowing
- XR of ankle - ball and socket
- XR of foot for tarsal coalition
- Long film XR with blocks to determine LLD
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- Type 1 = present but hypoplastic fibula
- Type 2 = completely absent fibula
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- Type 1 = foot reconstructable (at least 3 rays)
- Further subdivided in to 4 types based on LLD at the point of diagnosis:
- 1A = < 6%
- 1B = 6-10%
- 1C = 11-30%
- 1D = >30%
- Type 2 = Foot not reconstructable
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- Mx is dependant on foot reconstructibility, and LLD
- Goals = stable knee, foot and ankle while optimize LLD
- Mx guided by Birch classifx - Principles are contralateral epiphysiodesis +/- ipsilateral lengthening
- Type 1A = growth modulation (Epiphysiodesis of longer side)
- Type 1 B, C = add on ipsilateral distraction osteogenesis
- Type 1D, 2 = Amputation as cannot lengthen more than 30% due to NV compromise
- Syme’s Amputation (trans malleolar amputation with no calcaneum) or Byod’s amputation (flip calcaneum)
- Must remember to excise fibrocartilage Anlage that will cause posterolateral tethering
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- What are the variations of amputations at ankle?
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