SCAPHOID FRACTURES Flashcards
The scaphoid accounts for 60% to 70% of all carpal fractures
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Their incidence occurs in men between the ages
of 15 and 19 years
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75% to 80% of scaphoid fractures occur at the waist, 10% to 15%
occur at the proximal pole, and 5% to 10% occur distally
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greater than 70% of the scaphoid’s
intraosseous vascularity from the dorsal scaphoid branches of the radial artery
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A minor volar contribution comes
from the radial artery or its superficial palmar branch.
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20% of patients with negative radiographs have
an occult acute fracture
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MRI is the most sensitive
and specific imaging modality for diagnosing scaphoid fractures and
also allows assessment of osseous blood supply and soft tissue injuries
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Computed tomography (CT) scan reformatted in the long axis
of the scaphoid is slightly less sensitive and specific for identification
of scaphoid fracture, but has the advantage of superior bony detail.
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Indication of surgical intervention in scaphoid fracture
■ Greater than 1 mm ofdisplacement at the waist
■ Lateral intrascaphoid angle >35°
■ Bone loss or comminution
■ Dorsal intercalated segment instability
■ Malalignment
■ Any proximal pole fracture
Delayed presentation is also a relative indication for surgery
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Nonoperative treatment is reserved for nondisplaced scaphoid waist
and distal pole fractures
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For how long the immobilization of scaphiod fracture should stay?
Distal pole and tubercle fractures generally
require only 6 to 8 weeks to heal
scaphoid waist fractures usually require 12 weeks
Immobilization can be discontinued when
bony union has been demonstrated
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We advocate CT scan to confirm
healing between 10 and 12 weeks,
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headless compression screws, revolutionizing the treatment of
scaphoid fractures
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When there is bone loss or comminution, cancellous or corticocancellous autogenous bone graft from the distal
radius can be used to fill the void and aid in healing
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proximal pole fractures
are more easily visualized using a dorsal approach
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distal
pole fractures are amenable to a volar approach
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benefit and draw back of the volar approach
provides wide bony exposure,
facilitates correction of a humpback deformity using structural bone graft
the volar margin of the trapezium hinders retrograde screw placement
benefit and draw back of the dorsal approach
provides an unobstructed path for screw
placement, but exposure is more limited, and bone grafting for correction of a humpback deformity is more difficult from the dorsal approach. , the dorsal location of the dominant blood supply is at risk with distal exposure.
Progressive wrist range of motion and strengtheningis
initiated following bony union.
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incidence of nonunion is approximately 10%
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The incidence of nonunion increases with
delayed presentation, fracture comminution, smoking, incomplete immobilization, or errors in surgical technique
humpback deformity is present, a volar approach is recommended
such that the scaphoid can be extended and then held in alignment
with corticocancellous autogenous bone graft
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When nonunion is present in the absence of scaphoid flexion,
screw fixation and autogenous distal radius cancellous bone grafting
can be performed via a dorsal or volar approach
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Option of free vascularised bone graft
The 1,2 intercompartmental supra retinacular artery (l,2 ICSRA) flap
the medial femoral condyle free flap
In proximal pole nonunion in yung patinets ?
replacement of the entire proximal pole including the proximal articular surface may be indicated.
Options include nonvascularized osteochondral rib graft and a
vascularized free medial femoral trochlea osteochondral free flap
In patients who are older and have low functional
demand and in those who have developed arthritis of the radio scaphoid joint or irreducible flexion of the distal scaphoid fragment what is the option ?
salvage options such as proximal row corpectomy or limited intercarpal fusion are recommended
The triquetrum is the second most common carpal fracture
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Because ofthe scaphoid’s retrograde vascular supply, distal
pole and tubercle fractures have a low incidence ofnonunion and can
generally be treated nonoperatively.
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Waist fractures can
be addressed from either side
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Treatment
principles for scaphoid waist nonunion include debridement and
reduction of the fracture if necessary, rigid fixation, and bone grafting
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When nonunion is present in the absence of scaphoid flexion,
screw fixation and autogenous distal radius cancellous bone grafting
can be performed via a dorsal or volar approach
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