A Smith fracture is a fracture of the distal radius with volar (palmar) displacement or angulation of the distal fragment. It is the mirror image of the Colles fracture, hence the synonym reverse Colles fracture (also Goyrand fracture). It produces a “garden-spade” or reverse dinner-fork deformity and is best appreciated on the lateral radiograph. Smith fractures account for roughly 5% of distal radius and ulna fractures and are inherently unstable, so they often need surgical fixation.
Quiz
What is the typical mechanism of injury that produces a Smith fracture?
- Fall onto an outstretched hand with the wrist extended.
- Fall onto a flexed wrist, or a direct blow to the back of the wrist.
- Axial load through the thumb.
- Twisting injury at the elbow.
Mechanism and pathophysiology
- Mechanism: fall onto a flexed (volar-flexed) wrist, or a direct force to the dorsal aspect of the distal forearm. This drives the distal radial fragment volarly, the opposite of the Colles mechanism.
- Bimodal age distribution: high-energy trauma in younger men (road traffic, sport) and low-energy falls in older women with osteoporosis. Distal radius fractures are the most common upper-limb fracture, and between ages 64 and 94 women are about six times more likely than men to sustain one.
- Always assess for associated injuries: distal radioulnar joint (DRUJ) disruption, ulnar styloid fracture, carpal injury, and triangular fibrocartilage complex (TFCC) tears.
Key imaging features
- Lateral radiograph (most important): volar displacement and volar tilt of the distal radial fragment, reversing the normal 10-12 degrees of volar (palmar) tilt.
- PA radiograph: transverse or oblique distal radial fracture line; assess radial inclination and radial height.
- The fracture may be extra-articular or extend intra-articularly (reverse Barton pattern).
- Check for concomitant fractures and for radiocarpal or DRUJ malalignment.
Distal radius alignment: normal values and instability thresholds
| Parameter | Normal value | Suggests instability / surgery |
|---|---|---|
| Radial inclination | 21-25 degrees (mean ~23) | Loss of more than 5 degrees vs. the opposite side |
| Radial height (length) | 10-13 mm (mean ~12) | Radial shortening more than 5 mm |
| Volar (palmar) tilt | 10-12 degrees volar | Dorsal angulation more than 20 degrees (or loss of volar tilt) |
| Articular surface | Congruent, smooth | Intra-articular step-off or gap of 2 mm or more |
| Comminution | None | Dorsal/volar comminution (predicts re-displacement) |
Imaging recommendation
- Radiographs (PA and lateral wrist): first line for diagnosis and to differentiate from Colles and other distal radial injuries.
- CT: for comminuted or intra-articular fractures, to characterise articular step-off and plan surgical fixation.
- MRI: if TFCC injury, occult fracture, or associated soft-tissue or ligamentous injury is suspected.
Differential diagnosis: named distal radius fractures
| Fracture | Displacement / angulation | Articular involvement | Typical mechanism |
|---|---|---|---|
| Colles | Dorsal (dinner-fork deformity) | Extra-articular | Fall on outstretched, extended wrist |
| Smith (reverse Colles) | Volar (garden-spade deformity) | Extra- or intra-articular | Fall on flexed wrist / dorsal blow |
| Barton | Dorsal rim, radiocarpal fracture-dislocation | Intra-articular | Dorsal shear |
| Reverse (volar) Barton | Volar rim, radiocarpal fracture-dislocation | Intra-articular | Volar shear (equals Smith type II) |
| Chauffeur (Hutchinson) | Radial styloid | Intra-articular | Direct or avulsion injury |
Read our dedicated case on the Colles fracture for the dorsally displaced counterpart.
Thomas classification of Smith fractures
Smith fractures are subdivided by the Thomas classification (described by Thomas in 1957), based on fracture geometry and articular involvement. All three types share volar displacement; they differ in whether the fracture line is extra-articular, intra-articular, or juxta-articular.
| Type | Description | Articular involvement | Approx. frequency |
|---|---|---|---|
| Type I | Transverse fracture line; most common and most stable | Extra-articular | ~85% |
| Type II | Oblique fracture through the volar lip with volar dislocation of the carpus (reverse Barton pattern) | Intra-articular | ~13% |
| Type III | Oblique juxta-articular fracture with volar displacement and volar tilt of the distal radius | Juxta-articular | <2% |
Clinical features
- Immediate: pain and a volar “garden-spade” deformity, volar swelling, and a dorsally prominent ulna. Median or ulnar nerve compression may occur; acute carpal tunnel syndrome complicates up to 15% of cases.
- Delayed: malunion, tendon entrapment or rupture, chronic carpal tunnel syndrome, and complex regional pain syndrome.
- Who gets it: bimodal, affecting younger men after high-energy trauma and older osteoporotic women after low-energy falls.
Treatment
Smith fractures are inherently unstable because the volar displacing force is difficult to control with a cast, so a lower threshold for surgical fixation applies compared with Colles fractures.
- Non-displaced / stable: closed reduction and immobilisation in a below-elbow cast (wrist in slight extension and supination), with close radiographic follow-up for re-displacement.
- Displaced / unstable / intra-articular: open reduction and internal fixation, usually with a volar locking (buttress) plate. K-wires may be used for minimally comminuted patterns.
Operative indications (any of): intra-articular step-off of 2 mm or more, dorsal angulation more than 20 degrees, radial shortening more than 5 mm, comminution, or instability after reduction.
The 2020 AAOS/ASSH clinical practice guideline uses age 65 as a proxy for functional demand: in patients over 65, clinical outcomes at one year are similar with or without surgery, so nonoperative management is a reasonable option, whereas younger, higher-demand patients generally benefit from fixation. When surgery is chosen, the fixation technique is driven by fracture pattern rather than by any single implant being superior.
Etymology and synonyms
- Smith fracture is named after Robert William Smith, an Irish surgeon who described it in 1847.
- Also called reverse Colles fracture, because its displacement is opposite to the more common Colles fracture.
- The injury was earlier described by the French physician Jean-Gaspard-Blaise Goyrand, so it is also known as the Goyrand fracture.
Frequently Asked Questions
References
- Porrino JA Jr, Maloney E, Scherer K, Mulcahy H, Ha AS, Allan C. Fracture of the distal radius: epidemiology and premanagement radiographic characterization. AJR Am J Roentgenol. 2014;203(3):551-559. PMID: 25148157.
- Thomas FB. Reduction of Smith’s fracture. J Bone Joint Surg Br. 1957;39-B(3):463-470. PMID: 13463033.
- American Academy of Orthopaedic Surgeons / American Society for Surgery of the Hand. Management of Distal Radius Fractures Evidence-Based Clinical Practice Guideline. J Am Acad Orthop Surg. 2022. PMID: 35143462.
- Schroeder JD, Varacallo M. Smith Fracture Review. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2023. NBK547714.
- Saxton JA, Montgomery JR, Spicer PJ. An overview of the named wrist fractures. Contemp Diagn Radiol. 2021;44(24):1-5. doi:10.1097/01.cdr.0000800024.11881.ee.
Case co-authored by TeamGyan member Dr. Bhargavi Sovani. Illustrations by Dr. Bhargavi Sovani.
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Excellent, Detailed explanation,
in simple English.
Thanks, Sathya. Glad you liked it.