The patient (usually 14-40 years old) fell on an
outstretched hand, with the wrist held rigid and extended,
and now complains of pain, swelling, and decreased range of
motion in the wrist, particularly on the radial side.
Physical examination discloses no deformity, but pain with
motion and palpation and often swelling, especially in the
anatomic snuff box (on the radial side of the wrist, between
the tendon of the extensor pollicis longus and the tendons
of the abductor pollicis longus and extensor pollicis
brevis). A good sign is axial loading along the proximal
phalanx of the thumb, eliciting pain at the base.
What to do:
Apply ice and a temporary splint, check for distal
sensation and movement and other injuries; and order x rays
of the wrist, with special attention to the scaphoid bone
and its fat pad.
Regardless of whether a scaphoid fracture shows on x ray,
splint or cast the wrist in extension, with the thumb out in
opposition, and immobilized to its interphalangeal joint.
Explain to the patient the frequent difficulty of
visualizing scaphoid fractures on x rays, the frequent
difficulty in healing of scaphoid fractures due to variable
blood supply, and the resultant necessity of keeping this
splint or cast in place for a week.
Arrange for re-evaluation and further treatment within the
next few days.
Discussion
Because fractures of the scaphoid bone are common, because
they are often invisible on x ray until weeks later, because
the blood supply to the fractured area may be tenuous and
non-union or avascular necrosis likely, and because the
resultant pain and arthritis may severely limit hand
function, it is prudent practice to splint or cast all
potential scaphoid fractures with a thumb spica until
orthopedic re-evaluation in 1-2 weeks.
References:
Waeckerle JF: A prospective study identifying the
sensitivity of radiographic findings and the efficacy of
clinical findings in carpal navicular fractures. Ann Emerg
Med 1987;16:733-737.
