Orthopedic Gait

Question 1

Determinants of Gait

Answer 1

1. Pelvic rotation in the transverse plane (4deg posteriorly on stance leg & 4deg ant on swing)
2. Lateral pelvic tilt (~1in on swing size)
3. Lateral shift towards weight bearing side
4. 15-20deg knee flexion in early stance (for foot flat)
5. Ankle dorsiflexion early in stance
6. Heel rise in terminal stance

Question 2

Ground Reaction Forces

- ankle, knee & hip

Answer 2

ANKLE - When the weight is in the heel, the GRF is posterior to the ankle (IC & LR), when the weight is in the mid foot/toes the GRF is anterior to the ankle (MS,TS,PS)

KNEE: when the knee is flexed the GRF is posterior to the knee (LR,PS) & when the knee is extended the GRF is anterior to the knee (IC, MS, TS - prevents hyperextending in TS)

HIP: opposite of the ankle; during IC & LR the GRF is anterior to prevent hip flexion & during MS, TS, & PS the GRF is posterior to control hip extension

Question 3

Stance phase vs. Swing phase activated muscles

Answer 3

Stance phase - anterior/extensor muscles to prevent buckeling & stabilize pelvis

• IC: adductor magnus peak activation to
• MS: not much muscle activity, held upright by Iliofemoral ligament

Swing phase - flexor muscles to advance the leg & clear the toe

Question 4

Why do people have abnormal gait? (4)

Answer 4

1. Deformity (contractures, abnormal joint contours)
2. Muscular weakness
3. Pain (excessive tissue tension)
4. Sensory & motor impairments (proprioceptive, spasticity)

Question 5

PF Deformity

Answer 5

causes limited DF & usually due to an ankle sprain or PF contracture

compensations: increased hip or knee flexion to clear the toe

Question 6

Ankle Rigidity

Answer 6

due to wearing a rigid/solid AFO if instability or sprain

compensations: knee flexion moment in IC/LR to reach foot flat

Question 7

Knee Extension deformity

Answer 7

causing limited knee flexion which in turn means prolonged heel contact & excessive ankle DF during pre-swing

compensations: increased hip flexion, circumduction

Question 8

Knee flexion deformity

Answer 8

causes limited knee extension
- due to knee flexion contracture, or OA

compensations: increased DF during TS,PS

Question 9

Genu valgum/varum

Answer 9

valgum –> increased BOS

varum –> decreased BOS

Question 10

Hip flexion deformity

Answer 10

causes limited hip extension
- due to contracture or pain or tight IT band

compensations:
Stance - forward trunk lean & lumbar lordosis OR knee flexion

Question 11

Hip Extension deformity

Answer 11

causing limited knee flexion

compensations: increased hip flexion w/ posterior pelvic tilt

Question 12

Excessive Hip Adduction

Answer 12

aka Trendelenburg Sign
- due to weakness of glute med OR tightness of adductors on CONTRAlateral side

compensations: lateral trunk lean towards stance leg

Question 13

Excessive subtalar inversion

Answer 13

more prone to evert the ankle (compensation)

lacking contact on medial foot & prolonged contact on lateral foot

Question 14

Excessive subtalar eversion

Answer 14

prolonged inversion/contact on medial foot

& lacking lateral foot contact

Question 15

Position of Comfort of LE when painful & swollen

Answer 15

Hip = 30-40deg flexion
- will have increased trunk lean & increased DF
Knee = 30-60deg flexion
- will have flexed knee throughout gait
Ankle = 15deg PF
- decreased DF & toe drag

Question 16

Quadriceps weakness does what to gait?

Answer 16

causes knee hyperextension during mid-terminal stance in order to rely on bony alignment for stability

Question 17

Soleus weakness does what to gait?

Answer 17

causes toe drag during swing phase & sustained knee flexion in late stance because the soleus is responsible for stabilizing the tibia in order to get a strong quadriceps contraction