Pediatric emergency medicine trisk 838

FIGURE 109.7 These lateral radiographs of the finger demonstrate two examples of fractures
at the base of the distal phalanx in the setting of a mallet finger. (Courtesy of Children’s
Orthopaedic Surgery Foundation.)


FIGURE 109.8 Operative exploration of a Jersey finger injury, demonstrating the ruptured
flexor digitorum profundus tendon. (Courtesy of Children’s Orthopaedic Surgery Foundation.)

Proximal phalanx injuries are some of the most common pediatric hand injuries
and are managed similarly to middle phalangeal injuries. The base of the
proximal phalanx often endures a Salter–Harris II fracture (see Fig. 111.2 for
Salter-Harris Classification system), with the small (i.e., the fifth) finger being the
most frequently affected. Many are managed with splinting/casting following
closed reduction when necessary. Reduction can be an emergency room
procedure in appropriately trained hands using the “pen-in-the-web-space”
technique. Nondisplaced shaft fractures are generally managed with
immobilization. Displaced and angulated fractures may require surgical
stabilization. Phalangeal neck fractures can be difficult to diagnose. Oblique view
radiographs may be of assistance ( Fig. 109.10 ). These fractures require very
close outpatient care, as displacement and rotation may have long-term
consequences on the flexion of the adjacent IP joint. Finally, intra-articular
condyle fractures may involve one or both condyles and long-term management
may depend on the degree of displacement and severity of the injury ( Fig. 109.11
). Close follow-up is required in these injuries; many require surgical
stabilization. It is important to note that a finger splint does not provide adequate
support for a proximal phalanx fracture. A hand- or forearm-based splint is
necessary.


FIGURE 109.9 This lateral radiograph demonstrates a small volar avulsion fracture of the
proximal middle phalanx (A ), then a larger pilon fracture of the proximal middle phalanx (B ).

(Courtesy of Children’s Orthopaedic Surgery Foundation.)

Proximal phalanx injuries to the thumb are unique. In adolescents and adults, a
skier’s or gamekeeper’s thumb occurs with rupture of the ulnar collateral
ligament (UCL) during an abduction stress of the thumb. In children, a fracture of
the base of the proximal phalanx is more likely than a UCL injury, with Salter–
Harris I and II fractures predominating in younger children and Salter–Harris III
fractures in older children. Thumb spica splinting is appropriate for this
constellation of injuries in the emergency department. Extra-articular injuries may


require closed reduction prior to immobilization. Displaced intra-articular
fractures require operative management. Early hand specialist referral is
appropriate.

DISLOCATIONS
CLINICAL PEARLS AND PITFALLS
MCP dislocations can be difficult to identify on radiograph and may
simply appear hyperextended.
Avoid longitudinal traction with MCP joint reductions.

Clinical Considerations
Dislocations of the IP and metacarpophalangeal (MCP) joints are generally
uncommon in younger patients, although adolescents tend to have incidence
similar to adults, particularly when involved in contact sports.
Initial Assessment and Management
IP dislocations most often occur with the distal bone placed dorsal to the
proximal. After management of pain with either systemic analgesics or a digital
block, prompt relocation is performed with inline distraction and hyperextension
in the IP joints.

MCP joint dislocations most frequently involve the thumb ( Fig. 109.12 ).
These dislocations occur most often with the proximal phalanx dorsal to the
metacarpal and the metacarpal head palpable in the palm. In the immature patient,
these dislocations may be difficult to clarify on radiographs because of the joint
consisting mainly of cartilage or in the case of lesser digits, adjacent digit overlap
on imaging that makes diagnosis challenging. Therefore, the digit may simply
appear to be hyperextended. Reduction attempts should maintain or exaggerate
the hyperextension while applying pressure toward the palm on the base of the
phalanx. In general, straight longitudinal traction is not recommended in MCP
dislocations, to avoid soft tissue interposition and converting a reducible injury
into an irreducible dislocation. If the joint is not easily relocated, hand specialist
involvement is required for likely open reduction. In these cases, the tendons and
volar plate involved may prevent reduction with inline traction.