Scaphoid fracture is the most common carpal bone fracture. It accounts for 2% of all body bone fractures, and 60% of carpal bone fractures. It generally occurs after a fall onto the hand with the wrist in extension.
It is frequently misdiagnosed as a wrist sprain, and is sometimes unfortunately diagnosed too late.
ANATOMICAL REMINDER
The scaphoid is one of eight carpal bones. It is located at the outer end of the first row.
It is involved in flexion, extension and lateral tilting movements of the wrist.
SYMPTOMS AND CLINICAL EXAMINATION
A scaphoid fracture causes painful swelling of the wrist. The pain is located on the outer edge and dorsal surface of the wrist.
Active wrist mobility is rendered painful.
FURTHER TESTS
Scaphoid fractures are diagnosed on standard wrist X-rays.
In the case of strictly non-displaced fractures, it is sometimes difficult to see the fracture line, and the diagnosis is made by performing an emergency CT scan.
With the results of X-rays and sometimes CT scans, it is easier to visualize and classify the fracture according to its location, the type of fracture line and whether or not it has been displaced.
TREATMENT
In the case of strictly non-displaced fractures, orthopedic treatment can be performed by immobilizing the wrist in a cuff that does not support the thumb or elbow.
The immobilization period is 90 days. The duration of immobilization is linked to the slow rate of consolidation of this small bone.
In the case of non-displaced fractures, comfort can be improved by performing an almost scarless surgical procedure, directly through the skin, which consists of skewering or screwing the scaphoid bone in compression.
Another advantage of this surgical procedure is that it increases the rate of fracture healing.
In the case of a displaced scaphoid fracture, surgery is required to reduce the fracture and hold it in place (osteosynthesis) with a compression screw.
This operation is performed with a three-centimeter scar.
After the operation, the wrist is usually immobilized in a removable splint for three to four weeks, and rehabilitation is then started in accordance with the follow-up X-rays.
EVOLUTION
The patient is seen again one week after surgery, with a follow-up X-ray to ensure that the screw is in place and that there is no secondary displacement.
For the same reasons, he will be seen again one month after surgery.
He will be seen a final time three months after surgery to ensure that the fracture is perfectly solid.
The rate of non-union (pseudarthrosis) in non-operated scaphoid fractures is around 10%.
This high rate is linked to the anatomy of the scaphoid. In fact, this small bone is poorly vascularized (i.e. little blood feeds the bone).
This is why, in the event of a fracture, it takes more than 90 days to heal, and in 10 cases out of 100, the fracture does not heal.
When the scaphoid fracture is not solid, the wrist evolves towards deterioration. The scaphoid no longer plays its supporting role (the carpal bones can be compared to two rows of ossicles). If one of the ossicles is fractured, all the other ossicles collapse).
Over a period of a few years, the wrist degenerates, leading to generalized wear and tear of the wrist cartilage, resulting in osteoarthritis of the wrist.
Osteoarthritis manifests itself in reduced wrist mobility and chronic pain. In the case of scaphoid fractures, it is much easier to take action at an early stage, rather than at a late stage when osteoarthritic degradation has already occurred.
That’s why it’s so important to detect scaphoid fractures as early as possible.
