Musculoskeletal Injuries Answers 337holding it in a dependent position. A sensitive test used to diagnose carpal
tunnel is Phalen test.Have the patient hold the affected wrist in hyper-
flexion for 60 seconds. The test is positive if paresthesias or numbness
develops in the median nerve distribution.
(a)The ulnar nerve’s sensory distribution is over the fourth and fifth dig-
its. (d)The radial nerve’s sensory distribution is over the posterior hand.
(c)The axillary nerve’s sensory distribution is over the proximal arm. (e)The
musculocutaneous nerve’s sensory distribution is over the lateral forearm.
303.The answer is e.(Simon and Koenigsknecht, pp 123-126.) A boxer’s
fracture is a fracture of the neck of the fifth metacarpal.It is one of the
most common fractures of the hand and usually occurs from a direct
impact to the hand (eg, a punch with a closed fist).
(a)Colles fracture is the most common wrist fracture seen in adults. It
is a transverse fracture of the distal radial metaphysis, which is dorsally dis-
placed and angulated. It usually occurs from a fall on an outstretched hand.
(b)Smith fracture is a transverse fracture of the metaphysis of the distal
radius, with associated volar displacement and angulation (opposite of a
Colles). They typical occur secondary to a direct blow or fall onto the dor-
sum of the hand. (c)A scaphoid fracture is the most common fracture of
the carpal bones. It is typically seen in young adults secondary to a FOOSH.
(d)A Galeazzi fracture involves a fracture at the junction of the middle and
distal thirds of the radius, with an associated dislocation of the distal radial-
ulnar joint.
304.The answer is e. (Simon and Koenigsknecht, pp 489-491.) The
patient is showing signs and symptoms of compartment syndrome.The
syndrome occurs as a result of an increase in pressure within a confined
osseofascial space that impedes neurovascular function. The end result is
necrosis and damage to tissues. It can occur after crush injuries, circum-
ferential burns, hemorrhage, edema, or any process that increases com-
partment pressure. Clinically, the patient complains of pain that is out of
proportion to the injury. Physical examination may reveal swelling, sen-
sory deficits, and pain with passive motion. The presence of a pulse
does not rule out compartment syndrome.Late findings include pallor
of the skin, diminished or absent pulses, and a cool extremity. The only
way to diagnose compartment syndrome is to measure intracompart-
mental pressure with a Stryker device.A pressure greater than 30 mm Hg
is considered diagnostic and requires a fasciotomyto avoid tissue damage.