COMSAE Phase 1 Form 113:
Comprehensive Practice Exam with
Answers and Rationales/Instant
Download Pdf
THIS PRACTICE RESOURCE COVERS THE
CORE CONTENT AREAS TESTED
• ANATOMY AND EMBRYOLOGY
• PHYSIOLOGY AND PATHOPHYSIOLOGY
• BIOCHEMISTRY AND MOLECULAR
BIOLOGY
• MICROBIOLOGY AND IMMUNOLOGY
• PHARMACOLOGY
• PATHOLOGY
• OSTEOPATHIC PRINCIPLES AND
PRACTICE (OPP/OMM)
• CLINICAL REASONING AND PATIENT
MANAGEMENT
ON 1: ANATOMY AND EMBRYOLOGY
,Question 1
A 23-year-old man sustains a midshaft humeral fracture after a
fall. He is unable to extend his wrist or fingers. Which nerve is
most likely injured?
A) Median nerve
B) Ulnar nerve
C) Radial nerve
D) Axillary nerve
E) Musculocutaneous nerve
Answer: C) Radial nerve
Rationale: The radial nerve wraps around the spiral groove of
the humerus and innervates the triceps, brachioradialis, and all
wrist and finger extensors. Injury at this location causes "wrist
drop"—inability to extend the wrist and fingers.
Question 2
Which bone articulates with the acetabulum to form the hip
joint?
A) Tibia
B) Fibula
C) Femur
D) Patella
E) Pelvis
Answer: C) Femur
,Rationale: The femoral head articulates with the acetabulum of
the os coxae to form the hip joint. The acetabulum is a cup-
shaped socket formed by the fusion of the ilium, ischium, and
pubis.
Question 3
During development, failure of the neural tube to close at the
cranial end causes:
A) Spina bifida occulta
B) Anencephaly
C) Meningocele
D) Chiari malformation
E) Myelomeningocele
Answer: B) Anencephaly
Rationale: Neural tube defects result from failure of closure.
Cranial defects cause anencephaly, while caudal defects cause
spina bifida variants. Folic acid supplementation before and
during early pregnancy reduces the risk of neural tube defects.
Question 4
A patient presents with "foot drop" and a steppage gait. Which
nerve is most likely damaged?
A) Superficial peroneal nerve
B) Deep peroneal nerve
, C) Tibial nerve
D) Sural nerve
E) Common fibular nerve
Answer: B) Deep peroneal nerve
Rationale: The deep peroneal nerve innervates the tibialis
anterior, which is responsible for dorsiflexion of the foot.
Damage causes foot drop (inability to dorsiflex) with a
characteristic steppage gait. The common fibular nerve wraps
around the fibular neck and can be injured by trauma to that
area.
Question 5
The ligamentum teres (ligament of the head of the femur)
carries which artery?
A) Femoral artery
B) Obturator artery
C) Artery to the head of the femur
D) Deep femoral artery
E) Circumflex femoral artery
Answer: C) Artery to the head of the femur
Rationale: The ligamentum teres contains a branch of the
obturator artery that supplies the head of the femur. This artery
is important for femoral head perfusion, especially in children,
though its clinical significance in adults is limited.
Comprehensive Practice Exam with
Answers and Rationales/Instant
Download Pdf
THIS PRACTICE RESOURCE COVERS THE
CORE CONTENT AREAS TESTED
• ANATOMY AND EMBRYOLOGY
• PHYSIOLOGY AND PATHOPHYSIOLOGY
• BIOCHEMISTRY AND MOLECULAR
BIOLOGY
• MICROBIOLOGY AND IMMUNOLOGY
• PHARMACOLOGY
• PATHOLOGY
• OSTEOPATHIC PRINCIPLES AND
PRACTICE (OPP/OMM)
• CLINICAL REASONING AND PATIENT
MANAGEMENT
ON 1: ANATOMY AND EMBRYOLOGY
,Question 1
A 23-year-old man sustains a midshaft humeral fracture after a
fall. He is unable to extend his wrist or fingers. Which nerve is
most likely injured?
A) Median nerve
B) Ulnar nerve
C) Radial nerve
D) Axillary nerve
E) Musculocutaneous nerve
Answer: C) Radial nerve
Rationale: The radial nerve wraps around the spiral groove of
the humerus and innervates the triceps, brachioradialis, and all
wrist and finger extensors. Injury at this location causes "wrist
drop"—inability to extend the wrist and fingers.
Question 2
Which bone articulates with the acetabulum to form the hip
joint?
A) Tibia
B) Fibula
C) Femur
D) Patella
E) Pelvis
Answer: C) Femur
,Rationale: The femoral head articulates with the acetabulum of
the os coxae to form the hip joint. The acetabulum is a cup-
shaped socket formed by the fusion of the ilium, ischium, and
pubis.
Question 3
During development, failure of the neural tube to close at the
cranial end causes:
A) Spina bifida occulta
B) Anencephaly
C) Meningocele
D) Chiari malformation
E) Myelomeningocele
Answer: B) Anencephaly
Rationale: Neural tube defects result from failure of closure.
Cranial defects cause anencephaly, while caudal defects cause
spina bifida variants. Folic acid supplementation before and
during early pregnancy reduces the risk of neural tube defects.
Question 4
A patient presents with "foot drop" and a steppage gait. Which
nerve is most likely damaged?
A) Superficial peroneal nerve
B) Deep peroneal nerve
, C) Tibial nerve
D) Sural nerve
E) Common fibular nerve
Answer: B) Deep peroneal nerve
Rationale: The deep peroneal nerve innervates the tibialis
anterior, which is responsible for dorsiflexion of the foot.
Damage causes foot drop (inability to dorsiflex) with a
characteristic steppage gait. The common fibular nerve wraps
around the fibular neck and can be injured by trauma to that
area.
Question 5
The ligamentum teres (ligament of the head of the femur)
carries which artery?
A) Femoral artery
B) Obturator artery
C) Artery to the head of the femur
D) Deep femoral artery
E) Circumflex femoral artery
Answer: C) Artery to the head of the femur
Rationale: The ligamentum teres contains a branch of the
obturator artery that supplies the head of the femur. This artery
is important for femoral head perfusion, especially in children,
though its clinical significance in adults is limited.
