Hand Orthopedics Smith Fracture Criteria Calculator

About Smith fractures

A Smith fracture, which you'll also hear called a "reverse Colles," is a distal radius fracture where the distal fragment slips and angles toward the palm (volar). Robert William Smith described it back in 1847. It's fairly uncommon and makes up roughly 5% of distal forearm fractures. The usual mechanism is a fall onto a flexed wrist, or a direct blow to the back of the wrist. The shape it leaves behind sometimes gets called a "garden spade" deformity, basically the mirror image of the dorsal "dinner fork" you see with a Colles fracture.

Clinical criteria and how it is assessed

You diagnose it through exam and radiographs together. The features this calculator draws on:

• Volar displacement and volar angulation of the distal fragment, which is the finding that defines the injury on film.
• Swelling over the volar (palmar) side of the wrist, with the ulnar head looking relatively prominent on the dorsal side.
• An extra-articular pattern in the classic case, which is what sets it apart from the intra-articular volar Barton fracture.
• A "garden spade" deformity instead of the dorsal "dinner fork" of a Colles fracture.
• A chance of median and/or ulnar nerve compression (up to ~15%), which is why the neurovascular exam can't be skipped.

These fractures are unstable by nature, so a good number of them need careful reduction and, more often than not, surgical fixation with a volar plate.

Who uses this

Orthopedic and hand surgeons lean on these criteria, along with emergency physicians, radiologists, residents and physiotherapists. They help spot the volar pattern, judge stability and map out treatment.

FAQ

Why is it called a reverse Colles? The distal fragment shifts volarly, which is the opposite direction from the dorsal Colles fracture.

Does it usually need surgery? Smith fractures tend to be unstable, so surgical fixation comes up a lot, though the call really depends on the particular fracture.

This tool is educational only and does not replace a medical evaluation. A suspected distal radius fracture needs exam, radiographs and treatment decisions from a qualified clinician.