Synonyms in a broader sense
- Scaphoid fracture
- Fracture of the scaphoid
- Fracture of the Os scaphoideum (formerly Os naviculare)
- Scaphoid pseudarthrosis
- Fracture carpal bone
- Scaphoid pseudarthrosis
- Hand Injury
Definition Scaphoid fracture
The scaphoid fracture is the most common fracture in the carpal area. In most cases, a fracture of the scaphoid bone (Os scaphoideum) occurs when falling onto an extended wrist. The scaphoid fracture can be difficult to diagnose initially. In the absence of therapy, the fracture usually fails to heal and a so-called scaphoid pseudarthrosis develops.
Anatomy
The scaphoid (Os scaphoideum, formerly Os naviculare) is located on the thumb side in the first row of the wrist. It belongs to the most important carpal bones. It forms the wrist together with the lunate bone (Os lunatum) and the radius (spoke).
The scaphoid has a special blood circulation. The blood circulation is from distal, i.e. far from the wrist, to proximal (near the wrist). Therefore, the proximal third of the scaphoid has the most critical blood supply. More anatomy can be found under wrist.
Epidemiology
The typical age is between 20 and 30 years of age. The sex ratio is male to female 5:1. Overall, scaphoid fractures account for approximately 2% of all fractures.
The typical accident mechanism is the fall on the extended wrist. In order to suffer a scaphoid fracture, great force is required. Theoretical calculations come to a force of 200 – 400 kg to cause a scaphoid fracture.
The scaphoid is squeezed between the radius and the second row of wrist roots and breaks. Sometimes a scaphoid fracture occurs and is not noticed. A second fall event now causes complaints in the area of the scaphoid bone again and the x-ray shows the old scaphoid fracture.
Pain in a scaphoid fracture is typically indicated in the area of the thumb-side wrist. A pressure in the so-called tabatière is indicated as painful, as is the thumb sprain test. In some cases, the symptoms can be very mild.
