4.3 Multi-System Conditions

Multi-system conditions span across multiple body systems and age groups. The NPTE tests knowledge of geriatric, pediatric, and rehabilitation-specific conditions that require integrated clinical decision-making.

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Geriatric Considerations

Age-Related Changes Affecting PT

Fall Prevention

Falls are the leading cause of injury and injury-related death in adults 65+. Evidence-based PT interventions:

1. Exercise programs (MOST effective intervention):
   • Balance training (single leg stance, perturbation training)
   • Strengthening (especially hip abductors, knee extensors, ankle dorsiflexors)
   • Tai Chi (strong evidence for fall reduction)
2. Environmental modification: Remove tripping hazards, improve lighting, install grab bars
3. Medication review: Polypharmacy (5+ medications) significantly increases fall risk
4. Vision assessment: Refer for eye exam; multifocal lenses increase fall risk on stairs
5. Assistive devices: Proper fit and training for canes, walkers

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Pediatric Conditions

Cerebral Palsy (CP)

CP is a group of permanent movement disorders caused by non-progressive brain damage occurring before, during, or shortly after birth.

Classification by Motor Type:

GMFCS (Gross Motor Function Classification System):

Down Syndrome (Trisomy 21)

Key PT considerations:

• Atlantoaxial instability (AAI): Affects 10-20% of individuals with Down syndrome; excessive laxity at C1-C2 due to ligamentous laxity
  • Screening: Lateral cervical spine X-rays before participation in sports
  • Precautions: Avoid forced neck flexion, contact sports, somersaults if AAI confirmed
• Hypotonia: Low muscle tone is universal; affects motor development timeline
• Cardiac defects: ~50% are born with congenital heart defects (atrioventricular septal defect most common)
• Ligamentous laxity: Increased joint hypermobility;

affects all joints

• Developmental delays: Motor milestones delayed by 1-2 years on average

Spina Bifida

Functional outcomes depend on the level of the neural tube defect:

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Amputation Rehabilitation

Prosthetic Components by Level

Energy Expenditure by Amputation Level

Common Prosthetic Gait Deviations

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Orthotic Management of the Lower Extremity

Orthoses are high-yield. Ankle-foot orthoses (AFOs) control the foot and ankle and indirectly influence the knee:

A plantarflexion stop creates a knee-flexion moment at heel strike; a dorsiflexion stop creates a knee-extension moment in stance — understanding these biomechanical couplings explains why a given AFO is chosen for a given gait deviation.

Pediatric Developmental Milestones

Gross-motor milestone red flags are commonly tested: head control by ~4 months, independent sitting by ~6-8 months, crawling by ~9 months, pulling to stand by ~9-12 months, and independent walking by ~12-15 months (delayed if not walking by 18 months). Persistence of primitive reflexes beyond their expected integration window (e.g., ATNR beyond ~6 months) signals a CNS lesion such as cerebral palsy.

Prosthetic Training and Residual Limb Care

Early amputation management emphasizes residual-limb shaping with elastic wrapping or shrinkers (figure-of-eight, distal-to-proximal, more pressure distally) to control edema and produce a tapered, cylindrical limb for socket fit. Contracture prevention is critical: transtibial amputees tend toward knee flexion contracture, and transfemoral amputees toward hip flexion and abduction contractures, so prone positioning and avoiding pillows under the knee are taught early.

Beyond the gait deviations already covered, an abducted gait (wide base) suggests a prosthesis that is too long or a painful/ill-fitting medial socket wall, while excessive heel rise in swing indicates inadequate knee friction. Matching each deviation to its prosthetic, residual-limb, or strength cause is the core clinical-reasoning task the NPTE rewards.