Scaphoid Fractures

If you suffer from severe wrist pain or believe you might have a fracture, please Schedule an appointment with one of our orthopedic specialists as soon as possible

What is a Scaphoid Fracture?

Fractures of the scaphoid form the most commonly reported fractures of the carpus. The scaphoid bridges the distal and proximal carpal bones in the wrist, transfers compression loads from the hand to the forearm, and plays a critical role in maintaining carpal stability. The radial artery that penetrates the scaphoid and supplies 70%–80% of the bone provides most of the blood supply, leading to the problematic higher rate of avascular necrosis and non-union in more proximal fractures. The os central carpi (an uncommon accessory bone) resembles a fracture. This situation calls for differentiation, which the lack of degenerative changes and the rounded edges of an old fracture can help achieve. Fractures of the scaphoid often result from forcible extension of the wrist. Signs to watch out for in a scaphoid fracture include swelling and tenderness on the scaphoid tubercle and in the anatomical snuffbox (Krasin, 2001). 

The ramifications of a non-union fracture, such as carpal collapse and progressive degenerative changes have often led to a restrictive treatment regime with 8-12 weeks of immobilization.  However, in the case of a nondisplaced scaphoid wrist fracture, the most common among scaphoid fractures, union can occur after just four to six weeks of immobilization (Clementson, Björkman and Thomsen, 2020).

Epidemiology of a Scaphoid Fracture

Known as the most commonly fractured carpal bone, the scaphoid accounts for 11% of hand fractures, 60% of carpal fractures, and 2% of all fractures.  Scaphoid fractures most commonly occur in young males aged 15-25 years. These fractures often occur after a sports trauma involving a fall on an outstretched hand, with patients complaining of radial-sided wrist pain. Waist area fractures account for two-thirds of all scaphoid fractures, of which non-displaced form the majority. Fractures in the distal third of the scaphoid represent about a quarter of scaphoid fractures, while fractures in the proximal third form 5–10% of all scaphoid fractures (Clementson, Björkman and Thomsen, 2020). Scaphoid fracture remains uncommon in elderly persons and children. Children tend to fracture the distal radial epiphysis more often while the elderly fracture the distal radius more often (Krasin, 2001).

How Do Specialists Classify Scaphoid Fractures?

Classification of scaphoid fractures will take the stability and location of the fracture into account. For example, classifications based on location include distal one third, proximal one third, waist, tuberosity, and osteochondral fracture.  Classification with regards to stability depends on whether a displacement has occurred. Experts classify displaced fractures as unstable if the fracture fragments move or if a displacement more than 1 mm happens and classify non-displaced fracture as stable. A lunocapitate angle more than 15° or a scapholunate angle more than 60° makes a fracture unstable (Krasin, 2001). 

Diagnosing Scaphoid Fractures

Part of a clinical investigation involves comparing the injured hand with the uninjured hand. The three most commonly used clinical tests for evaluation of patients with suspected scaphoid fracture include:  scaphoid tubercle tenderness, anatomical snuff box tenderness, and pain on axial compression of the thumb.  Of these, pain on axial compression of the thumb has shown as the weakest diagnostic indicator. Radiological investigations, including MRI scan, computed tomography, and CT scan also help in diagnosis (Clementson, Björkman and Thomsen, 2020).

What is the Treatment for a Scaphoid Fracture?

Most acute scaphoid fractures heal with a below elbow cast, which includes immobilization of the thumb (scaphoid cast). Unstable fractures will require surgery (open or closed reduction and fixation). After surgery, the hand gets placed in a below elbow or an above elbow cast for different time periods, depending on the surgeon’s preference. The use of compression screws allows for earlier movement of the wrist. New studies mention the use of arthroscopically assisted reduction of unstable scaphoid fractures as a means of doing an accurate reduction with minimal surgical trauma and earlier movement of the hand (Krasin, 2001).

Please do not hesitate to contact us if you have any questions.

References

Clementson, M., Björkman, A. and Thomsen, N.O.B. (2020). Acute scaphoid fractures: guidelines for diagnosis and treatment. EFORT Open Reviews, [online] 5(2), pp.96–103. Available at: https://pubmed.ncbi.nlm.nih.gov/32175096/ [Accessed 22 Feb. 2022].

Krasin, E. (2001). Review of the current methods in the diagnosis and treatment of scaphoid fractures. Postgraduate Medical Journal, [online] 77(906), pp.235–237. Available at: https://pubmed.ncbi.nlm.nih.gov/11264484/ [Accessed 22 Feb. 2022].