A patient with a transfemoral (above-knee) amputation demonstrates lateral trunk lean toward the prosthetic side during gait. The MOST likely cause is:

Weak hip abductors on the prosthetic side. Lateral trunk lean toward the prosthetic side is most commonly caused by weak hip abductors (gluteus medius) on the amputated side, which cannot stabilize the pelvis during stance. Other causes include a prosthesis that is too short or a socket that is too wide. Strengthening the hip abductors and ensuring proper prosthetic fit are the primary interventions.

A child with Down syndrome is being screened for sports participation. The PT should be most concerned about:

Atlantoaxial instability at C1-C2. Atlantoaxial instability (AAI) at C1-C2 affects 10-20% of individuals with Down syndrome due to ligamentous laxity. This is a critical safety concern for sports participation, as excessive cervical flexion could cause spinal cord compression. Lateral cervical spine X-rays should be obtained before clearance for contact sports, gymnastics, or diving.

The MOST effective single intervention for reducing fall risk in older adults is:

Exercise programs (balance, strengthening, Tai Chi). Exercise programs combining balance training, strengthening (especially hip abductors and knee extensors), and activities like Tai Chi have the strongest evidence for reducing fall risk in older adults. While environmental modifications and medication review are important components of a comprehensive fall prevention strategy, exercise is the single most effective intervention.

Spastic cerebral palsy, the most common type, is caused by damage to which brain area?

Motor cortex / corticospinal tract. Spastic CP (70-80% of all CP cases) results from damage to the motor cortex or corticospinal tract (UMN pathway). This produces increased muscle tone (spasticity), hyperreflexia, and abnormal movement patterns. Dyskinetic/athetoid CP involves the basal ganglia, and ataxic CP involves the cerebellum.

4.3 Multi-System Conditions | NPTE Physical Therapy Exam | Free Exam Prep

Key Takeaways

Geriatric considerations: sarcopenia, fall risk screening, polypharmacy effects, deconditioning; exercise (strength, balance, aerobic) is the most effective intervention for fall prevention
Pediatric conditions: cerebral palsy is classified by GMFCS levels (I-V); Down syndrome requires atlantoaxial instability screening; spina bifida functional level depends on lesion level
Amputation rehabilitation: prosthetic training follows residual limb shaping, desensitization, strengthening, prosthetic fitting, gait training progression
Transtibial (below-knee) amputees have better energy expenditure for ambulation (10-40% increase) compared to transfemoral (above-knee, 60-100% increase)
Orthotics: AFO types include solid (most support, blocks PF and DF), hinged (allows DF, blocks PF), and posterior leaf spring (allows PF and DF, assists DF in swing)
Common gait deviations with prosthetics: lateral trunk lean (weak hip abductors or short prosthesis), circumduction (excessive prosthetic length or limited knee flexion), vaulting (prosthesis too long)
Cerebral palsy types: spastic (most common, UMN, 70-80%), dyskinetic/athetoid (basal ganglia, involuntary movements), ataxic (cerebellar, balance/coordination deficits)
Down syndrome precautions: atlantoaxial instability (C1-C2) affects 10-20% — avoid forced neck flexion; hypotonia, ligamentous laxity, and cardiac defects are common

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.

Geriatric Considerations

Age-Related Changes Affecting PT

System	Age-Related Change	Clinical Implication
Musculoskeletal	Sarcopenia (muscle loss), decreased bone density	Strength training, weight-bearing exercise, fall prevention
Cardiovascular	Decreased maximal HR, arterial stiffness, decreased CO	Adjusted exercise prescription, monitor BP response
Neurological	Slower reaction time, decreased proprioception	Balance training, environmental modification
Pulmonary	Decreased chest wall compliance, reduced vital capacity	Breathing exercises, endurance training
Integumentary	Thinner skin, decreased wound healing	Skin protection, pressure injury prevention

Fall Prevention

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

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)
Environmental modification: Remove tripping hazards, improve lighting, install grab bars
Medication review: Polypharmacy (5+ medications) significantly increases fall risk
Vision assessment: Refer for eye exam; multifocal lenses increase fall risk on stairs
Assistive devices: Proper fit and training for canes, walkers

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:

Type	Brain Area	Characteristics	Frequency
Spastic	Motor cortex/corticospinal tract (UMN)	Increased tone, hyperreflexia, scissors gait	70-80%
Dyskinetic/Athetoid	Basal ganglia	Involuntary writhing movements, fluctuating tone	10-15%
Ataxic	Cerebellum	Poor balance, coordination, intention tremor	5-10%
Mixed	Multiple areas	Combination of types	Variable

GMFCS (Gross Motor Function Classification System):

Level	Description
Level I	Walks without limitations
Level II	Walks with limitations (difficulty on uneven surfaces, stairs)
Level III	Walks with handheld assistive device
Level IV	Self-mobility with powered wheelchair; may stand for transfers
Level V	Transported in manual wheelchair; limited ability to maintain head/trunk control

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:

Level	Key Muscle Function	Mobility Expectation
Thoracic	No LE function	Wheelchair primary; standing frame
L1-L2	Hip flexors	Household ambulation with HKAFO and walker
L3-L4	Quadriceps, hip adductors	Community ambulation with KAFO/AFO and crutches
L5	Ankle dorsiflexors, hip abductors	Community ambulation with AFO
S1-S2	Ankle plantarflexors	Community ambulation, may need shoe insert only

Amputation Rehabilitation

Prosthetic Components by Level

Level	Prosthesis Components
Transtibial (below knee)	Socket, pylon, foot/ankle unit; may include gel liner, suspension sleeve
Transfemoral (above knee)	Socket, knee unit, pylon, foot/ankle unit
Hip disarticulation	Socket encompasses pelvis, hip joint, knee unit, pylon, foot

Energy Expenditure by Amputation Level

Level	Energy Increase vs. Normal Ambulation	Gait Speed
Unilateral transtibial	10-40% increase	Slightly decreased
Bilateral transtibial	40-60% increase	Moderately decreased
Unilateral transfemoral	60-100% increase	Significantly decreased
Bilateral transfemoral	>200% increase	Severely decreased; many use wheelchair

Common Prosthetic Gait Deviations

Deviation	Possible Cause
Lateral trunk lean (toward prosthetic side)	Weak hip abductors, short prosthesis, wide-based socket
Circumduction	Prosthesis too long, inadequate knee flexion, weak hip flexors
Vaulting (rising on sound toe)	Prosthesis too long, inadequate socket suspension
Foot slap	Insufficient heel resistance in prosthetic foot
Terminal impact (abrupt knee extension)	Insufficient knee friction, forceful hip flexion

NPTE Physical Therapy Exam

1Introduction: NPTE Exam Overview

2Chapter 1: Musculoskeletal System

3Chapter 2: Neuromuscular & Nervous Systems

4Chapter 3: Cardiovascular & Pulmonary Systems

5Chapter 4: Integumentary & Other Body Systems

6Chapter 5: Non-Systems (Equipment, Safety & Professional Practice)