A 17 year old male presents to the ED with right 
wrist and hand pain two hours after falling on his 
out-stretched (extended) right hand.  The patient was 
jogging along the sidewalk when he lost his balance, 
tripped on the curb and broke his fall by landing on his 
out-stretched right hand.  There was no loss of 
consciousness and the only area of pain was his right 
wrist.
     Exam:  Except for some very superficial palmar 
abrasions, there were no other visible signs of external 
trauma over the entire right upper extremity from the 
clavicle to the tips of the fingers.  The shoulder and 
elbow both demonstrated full range of motion without 
any pain.  His fingers were all pink with intact 
neurovascular integrity. Upon closer examination of the 
wrist, the patient complained of point tenderness in the 
floor of the anatomic snuff box.  This point tenderness 
was exacerbated with wrist flexion, extension and radial 
deviation.  Because of point tenderness in this area, 
radiographs were obtained to rule out a fracture.

View wrist radiographs:  AP view


View wrist radiographs:  Oblique view


     The lateral view of the wrist was not contributory so 
it is not included here.  A scaphoid view was also taken 
because of the area of tenderness over the scaphoid.

View scaphoid radiograph.


Questions:
     1)  What is the significance of point tenderness in 
the area of the scaphoid (navicular) bone?
     2)  How would you interpret the radiographs shown 
above?
     3)  What are the complications of this type of injury?
     4)  How should these types of injuries be managed 
in the ED and when should you consult an orthopedic 
surgeon?

     This set of radiographs were initially read by the 
emergency physician as normal.  However, a fracture 
was still suspected and the patient was placed in a 
thumb spica splint and given orthopedic referral 
arrangements.  A radiologist then read the radiographs 
as showing a tiny fracture of the scaphoid.  On the 
enlarged views of the scaphoid, there is a slight 
irregularity of the cortex on the lateral side.  You may 
have to adjust the brightness and contrast on your 
monitor to appreciate this.  A second radiologist 
disagreed and insisted that these radiographs were 
normal.

Teaching Points:
     a)  Point tenderness in the "anatomic snuff box" 
region should always alert one to the possibility of a 
scaphoid (navicular) fracture.  The scaphoid bone is the 
most commonly fractured carpal bone.  These types of 
fractures are most commonly seen in patients between 
15 and 35 years of age as a result of a forceful 
hyperextension type injury to the wrist.

View another example.


     This patient complained of distal forearm pain.  The 
scaphoid region was not specifically examined.  This
pitfall must be avoided.  A forearm film which included 
the wrist was obtained.  A distal radius fracture and an 
ulnar styloid fracture were noted.  At the very top of the 
film, where it ends, a fracture through the scaphoid was 
noted.  Patients may not complain of pain exactly over 
the fracture site, especially when there are fractures 
elsewhere.  However, examination for the location(s) of 
point tenderness will usually improve the clinician's 
ability to locate the site of injury.

View another example.


     This radiograph shows another scaphoid fracture.  
However even in the absence of such a radiographically 
evident fracture, point tenderness over the scaphoid 
warrants the same treatment.

View the anatomic snuff box.


     The arrow points to the floor of the anatomic snuff 
box.  The scaphoid bone forms the floor of the anatomic 
snuff box.  Tenderness in the area should raise the 
suspicion of a scaphoid fracture.

     b)  The blood supply to the scaphoid penetrates 
the cortex at both the distal aspect (on the dorsal 
aspect near the scaphoid turbercle) and the waist 
(middle third of the scaphoid).  Because of this tenuous 
blood supply, there is no direct blood supply to the 
proximal third of the scaphoid.  Therefore, scaphoid 
fractures (even if properly diagnosed and treated) have 
a tendency for dreaded complications, such as 
avascular necrosis of the proximal third and non-union.  
In general, the more proximal the fracture, the greater 
the likelihood of avascular necrosis.
     c)  Although adults are more likely to present with 
fractures involving the middle third or proximal aspect of 
the scaphoid, children have a higher incidence of 
fractures involving the distal third of the scaphoid.
     d)  If one is clinically suspicious of a scaphoid 
fracture, always be sure to obtain isolated scaphoid 
views in addition to the standard AP, lateral and oblique 
views of the wrist.  Even if there is no obvious 
radiographic evidence of a scaphoid fracture, all 
patients with point tenderness over the anatomic snuff 
box region should be properly immobilized in the ED 
and referred to an orthopedist for further evaluation and 
management.
     e)  Proper immobilization of a scaphoid fracture 
should prevent wrist flexion/extension, radial wrist 
deviation and any movement of the thumb metacarpal.  
Therefore a simple volar wrist splint would NOT be 
considered proper immobilization for a scaphoid 
fracture.  A more adequate immobilization technique 
would be to apply a thumb spica/radial gutter splint 
(which could also be combined with a volar wrist splint).

View thumb spica/radial gutter splint.


     Only the radial gutter and thumb immobilizing 
portion of the splint is shown here without the overlying 
elastic wrap.  The thumb is immobilized to prevent wrist 
ab/ad-duction and first metacarpal movement.  A volar 
splint can be added to this.

     f)  Definitive treatment by an orthopedic surgeon 
usually involves a thumb spica cast for 6-12 weeks.

References
     1.  Simon RR, Koenigsknecht SJ:  Emergency 
Orthopedics:  The Extremities (second edition).
Appleton & Lange, pp. 81-84, 1987.
     2.  Letts RM:  Management of Pediatric Fractures.  
Churchill Livingston, pp.  389-396, 1994.
     3.  Etzwiler LS.  Hand and Wrist Injuries.  In:
Barkin R (ed).  Pediatric Emergency Medicine Concepts 
and Clinical Practice.  Chicago, Mosby Year Book, 
1992, p. 332.