ABC Orthotics/Prosthetics Board Written Exam
Complete Practice Question Bank & Study Guide
QUESTION 1
The functions of the tibialis posterior muscle are:
A. Plantar flexion and inversion
B. Plantar flexion and eversion
C. Dorsiflexion and inversion
D. Dorsiflexion and eversion
Correct Answer: A. Plantar flexion and inversion
Rationale: The tibialis posterior has primary actions of plantar flexion and
inversion of the foot. This is a fundamental anatomical question frequently
tested on the ABC written exam .
QUESTION 2
The distal aspect of the tibia articulates with which bones?
A. Calcaneus and fibula
B. Calcaneus and talus
C. Talus and fibula
D. Talus and navicular
Correct Answer: C. Talus and fibula
Rationale: The distal tibia articulates with the talus inferiorly and the fibula
laterally at the ankle mortise. This anatomical relationship is critical for
understanding ankle joint function and orthotic management .
,QUESTION 3
Anterior compression fractures of the spine involve which column?
A. Posterior column
B. Anterior column
C. Middle column
D. Anterior and posterior columns
Correct Answer: B. Anterior column
Rationale: Anterior compression fractures involve the anterior column of the
spine. Understanding spinal column biomechanics is essential for orthotic
management of spinal fractures .
QUESTION 4
Which muscle has its insertion at the adductor tubercle?
A. Adductor longus
B. Adductor brevis
C. Semitendinosus
D. Adductor magnus
Correct Answer: D. Adductor magnus
Rationale: The adductor magnus inserts at the adductor tubercle of the
femur. This landmark is important for prosthetic socket design and
alignment .
QUESTION 5
At initial contact during gait, the body weight line is:
,A. Anterior to the ankle and posterior to the knee
B. Posterior to the ankle and posterior to the knee
C. Posterior to the ankle and anterior to the knee
D. Anterior to the ankle and anterior to the knee
Correct Answer: A. Anterior to the ankle and posterior to the knee
Rationale: At initial contact, the body weight line passes anterior to the ankle
and posterior to the knee. This creates a plantarflexion moment at the ankle
and an extension moment at the knee. Understanding this is critical for
proper alignment of orthoses and prostheses .
QUESTION 6
The congenital abnormality of the spine in which one side of the vertebra is
incompletely developed is:
A. Hemivertebra
B. Spina bifida
C. Spondylolysis
D. Klippel-Feil syndrome
Correct Answer: A. Hemivertebra
Rationale: Hemivertebra is a congenital abnormality where one side of the
vertebra is incompletely developed, often leading to scoliosis. This condition
requires careful orthotic management .
QUESTION 7
Which muscle has the PRIMARY responsibility of rotating the thumb to
touch the tips of the index and middle fingers?
, A. Opponens pollicis
B. Flexor pollicis longus
C. Abductor pollicis brevis
D. Extensor pollicis longus
Correct Answer: A. Opponens pollicis
Rationale: The opponens pollicis is the primary muscle responsible for
opposition of the thumb, allowing rotation to touch the fingertips. This is a
fundamental anatomical question frequently tested on the orthotic written
exam .
QUESTION 8
What is the MOST important factor in decreasing the vertical loading of the
lumbar spine?
A. Application of a three-point pressure system for vertical stabilization
B. Enhancement of the abdominal hydropneumatic mechanism
C. Strengthening of the gluteal and abdominal musculature
D. Immobilization of the thoracolumbar spine
Correct Answer: B. Enhancement of the abdominal hydropneumatic
mechanism
Rationale: The abdominal hydropneumatic mechanism (increasing intra-
abdominal pressure) is the most important factor in decreasing vertical
loading of the lumbar spine. This principle underlies the design and function
of many spinal orthoses .
QUESTION 9
In which condition is a Milwaukee CTLSO contraindicated?
Complete Practice Question Bank & Study Guide
QUESTION 1
The functions of the tibialis posterior muscle are:
A. Plantar flexion and inversion
B. Plantar flexion and eversion
C. Dorsiflexion and inversion
D. Dorsiflexion and eversion
Correct Answer: A. Plantar flexion and inversion
Rationale: The tibialis posterior has primary actions of plantar flexion and
inversion of the foot. This is a fundamental anatomical question frequently
tested on the ABC written exam .
QUESTION 2
The distal aspect of the tibia articulates with which bones?
A. Calcaneus and fibula
B. Calcaneus and talus
C. Talus and fibula
D. Talus and navicular
Correct Answer: C. Talus and fibula
Rationale: The distal tibia articulates with the talus inferiorly and the fibula
laterally at the ankle mortise. This anatomical relationship is critical for
understanding ankle joint function and orthotic management .
,QUESTION 3
Anterior compression fractures of the spine involve which column?
A. Posterior column
B. Anterior column
C. Middle column
D. Anterior and posterior columns
Correct Answer: B. Anterior column
Rationale: Anterior compression fractures involve the anterior column of the
spine. Understanding spinal column biomechanics is essential for orthotic
management of spinal fractures .
QUESTION 4
Which muscle has its insertion at the adductor tubercle?
A. Adductor longus
B. Adductor brevis
C. Semitendinosus
D. Adductor magnus
Correct Answer: D. Adductor magnus
Rationale: The adductor magnus inserts at the adductor tubercle of the
femur. This landmark is important for prosthetic socket design and
alignment .
QUESTION 5
At initial contact during gait, the body weight line is:
,A. Anterior to the ankle and posterior to the knee
B. Posterior to the ankle and posterior to the knee
C. Posterior to the ankle and anterior to the knee
D. Anterior to the ankle and anterior to the knee
Correct Answer: A. Anterior to the ankle and posterior to the knee
Rationale: At initial contact, the body weight line passes anterior to the ankle
and posterior to the knee. This creates a plantarflexion moment at the ankle
and an extension moment at the knee. Understanding this is critical for
proper alignment of orthoses and prostheses .
QUESTION 6
The congenital abnormality of the spine in which one side of the vertebra is
incompletely developed is:
A. Hemivertebra
B. Spina bifida
C. Spondylolysis
D. Klippel-Feil syndrome
Correct Answer: A. Hemivertebra
Rationale: Hemivertebra is a congenital abnormality where one side of the
vertebra is incompletely developed, often leading to scoliosis. This condition
requires careful orthotic management .
QUESTION 7
Which muscle has the PRIMARY responsibility of rotating the thumb to
touch the tips of the index and middle fingers?
, A. Opponens pollicis
B. Flexor pollicis longus
C. Abductor pollicis brevis
D. Extensor pollicis longus
Correct Answer: A. Opponens pollicis
Rationale: The opponens pollicis is the primary muscle responsible for
opposition of the thumb, allowing rotation to touch the fingertips. This is a
fundamental anatomical question frequently tested on the orthotic written
exam .
QUESTION 8
What is the MOST important factor in decreasing the vertical loading of the
lumbar spine?
A. Application of a three-point pressure system for vertical stabilization
B. Enhancement of the abdominal hydropneumatic mechanism
C. Strengthening of the gluteal and abdominal musculature
D. Immobilization of the thoracolumbar spine
Correct Answer: B. Enhancement of the abdominal hydropneumatic
mechanism
Rationale: The abdominal hydropneumatic mechanism (increasing intra-
abdominal pressure) is the most important factor in decreasing vertical
loading of the lumbar spine. This principle underlies the design and function
of many spinal orthoses .
QUESTION 9
In which condition is a Milwaukee CTLSO contraindicated?
