ABC Orthotics/Prosthetics Board Written Exam
Complete Practice Question Bank & Study Guide 2026/2027
Questions 1–250
QUESTION 1
A Trendelenburg gait occurs with weakness of which muscle?
A. Gluteus medius
B. Gluteus maximus
C. Adductor magnus
D. Rectus femoris
Correct Answer: A. Gluteus medius
Rationale: The gluteus medius prevents contralateral pelvic drop during single-leg stance.
Weakness results in a Trendelenburg gait pattern .
QUESTION 2
In normal gait, the hip reaches maximum flexion during which phase?
A. Loading response
B. Initial contact
C. Midstance
D. Mid-swing
Correct Answer: B. Initial contact
Rationale: The hip is in maximum flexion at initial contact, approximately 30-35° .
QUESTION 3
An amputation that removes the midfoot and forefoot while saving the talus and
calcaneus is called a:
,A. Modified Symes
B. Lisfranc
C. Chopart
D. Transmetatarsal
Correct Answer: C. Chopart
Rationale: A Chopart amputation removes the midfoot and forefoot while preserving the
talus and calcaneus. Chopart is most likely to develop equinus contracture due to
unopposed pull of the gastrocnemius-soleus complex .
QUESTION 4
Which of the following muscles are transected in a transmetatarsal amputation?
A. Peroneus longus
B. Extensor hallucis longus
C. Tibialis posterior
D. Tibialis anterior
Correct Answer: B. Extensor hallucis longus
Rationale: The extensor hallucis longus is transected in a transmetatarsal amputation .
QUESTION 5
Which of the following is the primary flexor of the elbow?
A. Biceps brachii
B. Brachioradialis
C. Anconeus
D. Brachialis
Correct Answer: D. Brachialis
Rationale: The brachialis is the primary flexor of the elbow. The biceps brachii also flexes
the elbow but is a secondary flexor .
,QUESTION 6
The most common congenital absence of a long bone in the extremities is:
A. Fibular hemimelia
B. Proximal Focal Femoral Deficiency
C. Congenital hypoplasia of the Tibia
D. Tibial phocomelia
Correct Answer: A. Fibular hemimelia
Rationale: Fibular hemimelia is the most common congenital absence of a long bone in
the extremities .
QUESTION 7
A patient presents with a foot slap at initial contact. This gait deviation is most likely due
to weakness of which muscle?
A. Gastrocnemius
B. Soleus
C. Tibialis anterior
D. Peroneus longus
Correct Answer: C. Tibialis anterior
Rationale: Foot slap results from inadequate eccentric control of plantarflexion after heel
strike, indicating tibialis anterior weakness or poor prosthetic foot selection.
QUESTION 8
The stance phase of gait constitutes approximately what percentage of the gait cycle at
normal walking speed?
A. 40%
B. 50%
, C. 60%
D. 70%
Correct Answer: C. 60%
Rationale: The stance phase comprises approximately 60% of the gait cycle, while the
swing phase makes up the remaining 40% at normal walking speeds.
QUESTION 9
Which amputation level is MOST likely to develop an equinus contracture?
A. Chopart
B. Lisfranc
C. Symes
D. Transmetatarsal
Correct Answer: A. Chopart
Rationale: Chopart amputation is most likely to develop equinus contracture due to
unopposed pull of the gastrocnemius-soleus complex .
QUESTION 10
One advantage of a knee disarticulation amputation is:
A. The ability to maintain rotational control of the socket
B. The ability to bear weight on the distal end
C. The ability to match the knee center on the sound side
D. The ability to provide good cosmesis with the prosthesis
Correct Answer: A. The ability to maintain rotational control of the socket
Rationale: Knee disarticulation preserves the femoral condyles, which provide excellent
rotational control and weight-bearing surface .
Complete Practice Question Bank & Study Guide 2026/2027
Questions 1–250
QUESTION 1
A Trendelenburg gait occurs with weakness of which muscle?
A. Gluteus medius
B. Gluteus maximus
C. Adductor magnus
D. Rectus femoris
Correct Answer: A. Gluteus medius
Rationale: The gluteus medius prevents contralateral pelvic drop during single-leg stance.
Weakness results in a Trendelenburg gait pattern .
QUESTION 2
In normal gait, the hip reaches maximum flexion during which phase?
A. Loading response
B. Initial contact
C. Midstance
D. Mid-swing
Correct Answer: B. Initial contact
Rationale: The hip is in maximum flexion at initial contact, approximately 30-35° .
QUESTION 3
An amputation that removes the midfoot and forefoot while saving the talus and
calcaneus is called a:
,A. Modified Symes
B. Lisfranc
C. Chopart
D. Transmetatarsal
Correct Answer: C. Chopart
Rationale: A Chopart amputation removes the midfoot and forefoot while preserving the
talus and calcaneus. Chopart is most likely to develop equinus contracture due to
unopposed pull of the gastrocnemius-soleus complex .
QUESTION 4
Which of the following muscles are transected in a transmetatarsal amputation?
A. Peroneus longus
B. Extensor hallucis longus
C. Tibialis posterior
D. Tibialis anterior
Correct Answer: B. Extensor hallucis longus
Rationale: The extensor hallucis longus is transected in a transmetatarsal amputation .
QUESTION 5
Which of the following is the primary flexor of the elbow?
A. Biceps brachii
B. Brachioradialis
C. Anconeus
D. Brachialis
Correct Answer: D. Brachialis
Rationale: The brachialis is the primary flexor of the elbow. The biceps brachii also flexes
the elbow but is a secondary flexor .
,QUESTION 6
The most common congenital absence of a long bone in the extremities is:
A. Fibular hemimelia
B. Proximal Focal Femoral Deficiency
C. Congenital hypoplasia of the Tibia
D. Tibial phocomelia
Correct Answer: A. Fibular hemimelia
Rationale: Fibular hemimelia is the most common congenital absence of a long bone in
the extremities .
QUESTION 7
A patient presents with a foot slap at initial contact. This gait deviation is most likely due
to weakness of which muscle?
A. Gastrocnemius
B. Soleus
C. Tibialis anterior
D. Peroneus longus
Correct Answer: C. Tibialis anterior
Rationale: Foot slap results from inadequate eccentric control of plantarflexion after heel
strike, indicating tibialis anterior weakness or poor prosthetic foot selection.
QUESTION 8
The stance phase of gait constitutes approximately what percentage of the gait cycle at
normal walking speed?
A. 40%
B. 50%
, C. 60%
D. 70%
Correct Answer: C. 60%
Rationale: The stance phase comprises approximately 60% of the gait cycle, while the
swing phase makes up the remaining 40% at normal walking speeds.
QUESTION 9
Which amputation level is MOST likely to develop an equinus contracture?
A. Chopart
B. Lisfranc
C. Symes
D. Transmetatarsal
Correct Answer: A. Chopart
Rationale: Chopart amputation is most likely to develop equinus contracture due to
unopposed pull of the gastrocnemius-soleus complex .
QUESTION 10
One advantage of a knee disarticulation amputation is:
A. The ability to maintain rotational control of the socket
B. The ability to bear weight on the distal end
C. The ability to match the knee center on the sound side
D. The ability to provide good cosmesis with the prosthesis
Correct Answer: A. The ability to maintain rotational control of the socket
Rationale: Knee disarticulation preserves the femoral condyles, which provide excellent
rotational control and weight-bearing surface .
