Scaphoid Fracture
Relevant Anatomy and Implications
The scaphoid is a carpal bone located on the radial side of the wrist, sitting between the distal radius proximally and the trapezium/trapezoid distally.
It articulates with:
- Distal radius proximally
- Lunate medially / ulnarly
- Capitate medially and distally
- Trapezium and trapezoid distally
The scaphoid has a mainly retrograde blood supply from predominantly the dorsal carpal branch of the radial artery (the blood vessel enters the scaphoid around the distal pole and then travels backwards towards the proximal pole)
As a result:
- The distal pole generally has a better blood supply
- The proximal pole has relatively poorer perfusion
- A fracture through the scaphoid waist can interrupt blood flow to the proximal pole
- This increases the risk of avascular necrosis and non-union in proximal pole scaphoid fractures (compared to distal pole fractures)
The main complications of scaphoid fracture are avascular necrosis, delayed union and non-union.
These complications are more likely in:
- Proximal pole fracture
- Displaced fracture
- Delayed diagnosis / immobilisation / management
Causes and Risk Factors
Most common cause: sports-related trauma [Ref]
Mechanism of injury: FOOSH onto an extended wrist [Ref]
Epidemiology: [Ref]
- Most common in 15-25 y/o males
- Scaphoid is the most commonly fractured carpal bone
Clinical Features
Patients typically present with post-traumatic radial-sided wrist pain
3 commonly used clinical tests: [Ref]
| Clinical test | Description |
|---|---|
| Anatomical snuff box tenderness | The anatomical snuffbox is a hollow area on the radial side of the wrist, at the base of the thumb. It is most obvious when the patient extends / abducts the thumb (e.g. making a “thumbs up” position)
Borders of the anatomical snuffbox:
|
| Scaphoid tubercle tenderness | The scaphoid tubercle can be palpated on the palmar / volar aspect of the radial wrist, near the base of the thenar eminence, just distal to the distal wrist crease. |
| Pain on axial loading of the thumb | How to perform: hold the patient’s thumb and apply longitudinal compression along the thumb / 1st metacarpal towards the wrist
A positive test is pain felt at the radial wrist / scaphoid region |
The sensitivity for these three individual tests is reported to be 100%, and specificity increases to 74% if all three tests are positive. However, pain on axial compression of the thumb has the weakest diagnostic performance and cannot stand alone as a predictor. [Ref]
Investigation and Diagnosis (Initial Assessment)
Initial investigation: X-ray (scaphoid series – with 4 specific radiographic views)
Subsequent actions depending on the initial X-ray:
| Initial X-ray finding | Subsequent action / management |
|---|---|
| X-ray confirms scaphoid fracture |
|
| Normal X-ray (but a scaphoid fracture is suspected clinically) |
|
Rationale:
Scaphoid fractures cannot be diagnosed clinically with certainty and require radiological confirmation. However, initial plain X-rays have limited sensitivity, detecting no more than around 70% of scaphoid fractures. Therefore, a normal initial X-ray does not reliably exclude a scaphoid fracture, especially if clinical suspicion remains high. This is why suspected scaphoid fractures require a structured diagnostic pathway, with immobilisation and further imaging, such as MRI (which has a sensitivity of 99-100%).
Management (Specialist Care / Definitive Management)
| Management approach | Indications |
|---|---|
Operative management:
|
Surgery to be performed within 2 weeks of the injury if ANY of the following:
|
Conservative management:
|
Offer conservative management if there are NONE of the above indications for operative management
Further operative management is indicated if:
|
Delayed presentation management:
If a patient with a minimally displaced scaphoid waist fracture presents >4 weeks after the injury (i.e. delayed immobilisation):
- Perform a CT to assess for fracture healing / union
- If there is no evidence of union → consider operative management
Normally, a minimally displaced scaphoid waist fracture that presents early can usually be treated conservatively with immobilisation.