ABNORMAL SUPINATION

Question 1

CNS pathology types?

Answer 1

direct or indirect clonus

contracture of supinating muscles when antagonistic pronators develop flaccid paralysis

Question 2

no GRF on heel means?

Answer 2

STJ remains supinated

Question 3

▪ Characterized by flaccid paralysis of muscle (or less commonly by tonic muscle spasm)

▪ Flaccid paralysis of STJ pronators will, over time, lead to contracture of STJ supinators

▪ Tonic muscle spasm of supinators either directly or indirectly

Answer 3

Lower Motor Neuron Pathology for abnormal supination

Question 4

▪ Plantarflexed 1st ray and rigid forefoot valgus cause everted forefoot on rearfoot
▪ If forefoot inversion and 1st ray dorsiflexion can’t fully compensate for forefoot eversion → STJ will compensate by supinating

• Results from either:

o Too large a forefoot valgus of a plantarflexed 1st ray deformity or…
o 1
st ray and LMTJ have little to no motion for compensation

Answer 4

Everted Forefoot Position

Question 5

▪ Due to either congenital shortage of gastroc or congenital osseous deformity of ankle joint limiting dorsiflexion
▪ Will only result in a supination if heel is prevented from contacting ground during stance phase

• When heel can’t contact ground → supinators are not resisted
Equines Deformities
o Results in supination deformity

Answer 5

Equines Deformities