Cause: Active infectious disease characterized by fever, permanent motor paralysis and irreversible muscle atrophy, destruction of anterior horn cell of spinal cord. Primarily
children + young adults (2 – 4 years range) acute stage (Paralitic stage) – several days.
Deep tendon reflexes because hyperactive then diminish.
Progression of paralysis stops 48 hr's alter fever, initiates convalescent stage. Paralysed
muscle atrophies within first 2 months. Slower growth due to decrease in circulation.
Return of deep tendon reflexes and muscle power reaches limit by 8 months. Lower motor neuron lesion – flaccid, asymmetric paralysis with normal sensation. Polio patients highly motivated to be independent. Distribution of paralysis in lower limb usually involves longer muscle groups, quadriceps, tibialis anterior, triceps surae.
Gluteus medius + minimus.
Deformities             -Hip adduction contracture.
seen with Polio          - Knee flexion contracture.
- Iliotibial band contractures. (hip ext. rot. fl.)
- Long C curve scoliosis.
- Pelvic obliquity.

Clinical Picture
a / Flail ankle / foot complex with drop foot.
b / Valgus center deformity with pescavus.
c / Genu recurvatum and genu valgum.
d / Several wasting of thigh and lower leg musculature.
e / External rotation of foot on the leg.
f / Leg length discrepancy due to decreased blood supply causing slowed growth.
g / Trendelenburg gait to counter gluteus medius weakness.
h / Hyperlordosis to counteract gluteus maximus weakness.

Orthotic Management
1 / AFOs to act on the foot / ankle complex when knee is functionally stable or can be made so with an AFO.
- Trim AFO behind MT heads to allow any use of plantar flexion power during
push off of gait.
-    Genu recurvatum + Quad. weakness allow slight ankle plantar flexion.
-    Combined Tibialis anterior + triceps surae weakness = Rigid AFO.

2 / KAFO = If hip extensors unaffected may be used instead at Quads to maintain knee extension in stance.
- Plastic KAFO.
- Conventional KAFO