Abnormal/ Prosthetic gait

Tightness v. weakness

• Tightness

  • Contracture will decrease the range of motion in the opposite direction

  • Hip flexion contracture will lead to decreased hip extension on the same side and decrease in step on opposite side

    • FLOP: flexors tight, opposite side

• Weakness

  • will cause a decrease in the range of motion of the same motion

  • weakness of hip flexors will lead to a decreased hip flexion on the same side and decrease in step length on the same side

Magnet rule

• Weak muscles attract the trunk toward them in the same plane in STANCE

  • trunk follows muscle weakness, moves COM towards weak muscle to decrease work of the muscle

• Swing- opposite → Run away

Causes of backwards lean

• Weak hip extensors (stance)

• Hip flexion rigid contracture (stace)

• Glute max weakness

Excessive knee extension causes

• Quadriceps weakness

• excessive ankle plantarflexion (spasticity)

  • both lead to anterior pelvic tilt

Excessive Plantar Flexion

• Causes loss of progression: leads to shortened stride length and reduced velocity

• Low heel contact at initial contact and forefoot contact

  • 3 substitutions from this

    • premature heel off

    • knee hyperextension

    • forward trunk lean

Ankle/ foot deviations

• Excessive inversion (IPAD)

• Excessive Eversion (EDAB)

• Premature/ early heel off → tight PF

• Delayed heel contact → weak DF

• Toe Drag → weak DF/ tight PF

• Foot slap → weak DF

COM after amputation

• Lose LE, COM moves higher and to area with more mass

  • R LLE amp → COM moves up and to the left

• Lose UE, COM moves lower and to area with more mass

  • R UE amp → COM moves lower and to the left

• If amp. is unilateral- always on opp side of amp

• if bilateral w/ equal mass- COM is in the middle and higher up

AKA prosthesis- giat deviations

• Low wall

  • similar to weak muscles → lean towards low wall in stance

    • Low anterior thigh wall = weak quadriceps

    • Low lateral wall = weak abductors

• High walls

  • similar to tight muscles

    • high anterior thigh wall = tight hip flexors → pulls pelvis into anterior pelvic tilt

Gait deviations- AKA stance phase

• ALL IN STANCE

• Lateral bend- short prosthesis, inadequate lateral wall

• Abduction- long prothesis, hip joint fixed in abduction

• Lordosis- anterior socket wall discomfort (wall too high)

• Forward flexion- unstable knee, short walker

Gait deviations- AKA, mostly swing

• Early swing → High heel rise → slack extension aid

  • go into knee flexion too early

• Late swing → terminal impact → taught extension aid

  • go into extension too early

• Stance/ Heel off → Heel whip → knee bolt rotated; prothesis donned in malrotation

  • LIME Whip - Lat./ IR, Med./ER

• Heel contact → foot rotation → stiff heel cushion, malrotated foot

Hard and soft bumpers (Stops)

• If PF of the foot is restricted by stiff heel cushion or hard PF bumper (same thing as stop)

  • The amputee’s knee may have to flex through more than the normal range to allow the sole of the foot to reach the floor

  • Bumper will not absorb the impact of the heel striking the floor, thus tending to produce abrupt and excessive knee flexion

• Too soft heel cushion or soft PF bumper allows excessive compressibility of heel cushion

  • The ground reaction force passes anterior to the knee between heel strike and midstance

  • causes hyperextension of the knee joint

Orthotic gait cont’

• Anatomic cause

  • weak DF or spastic PF

• Orthotic cause

  • inadequate dorsiflexion assist/ inadequate plantarflexion stop

• Inadequate assist is similar to weak muscles

• Inadequate stop is similar to spastic muscles

• Gait deviations caused

  • Toe drag

  • circumduction

  • hip hiking

  • vaulting

Inspection of residual limb/ pressure sensitive/ tolerant areas

• Pressure-tolerant areas are expected to have redness following doffing of prosthesis

• Pressure- sensitive areas should have no redness after prosthesis use

• Pressure-sensitive areas

  • Anterior tibia

  • Anterior tibial crest

  • Fibular head and neck

  • Fibular nerve

• pressure-tolerant areas

  • Patellar tendon

  • medial tibial plateau

  • tibial and fibular shafts

  • distal end

Prosthetic-related- Vaulting, pelvic hike, circumduction in swing phase

• Prosthesis is too long

• locked knee unit

• Insufficient suspension

• Insufficient friction

• socket too small

• socket too loose

• Plantar flexed foot

Prosthetic-related- abducted prosthesis in stance phase

• High medial wall to prevent pinching

• inadequately adducted lateral wall

• prosthesis is too long

• hip joint abducted

Prosthetic-related- Lateral trunk bending in stance

• prothesis is too short

• Lateral wall is inadequate

• High medial wall

Prosthetic-related- Forward flexion during stance phase

• Unstable knee unit

• short walker or crutches

Prosthetic-related- excessive lordosis in stance

• inadequate socket flexion

Prosthetic-related- High heel rise during early swing phase (preswing)

• insufficient friction

• slack extension aid (excessive knee motion)

Prosthetic-related- Terminal swing impact

• Taught extension aid

• Insufficient friction

Prosthetic-related- Excessive foot rotation at heel contact

• stiff heel cushion

• malrotated foot

Prosthetic-related- medial/ lateral whips

• poorly fitting socket

• Medial: Knee bolt in ER

• Lateral: Knee bolt in IR

• Foot malrotated

• Prosthesis donned in malrotation

Prosthetic-related- Asymmetrical step lengths

• Decrease stance time

• Poor alignment of the prosthesis

• Uncomfortable socket

• Inadequately flexed socket