Scaphoid Fractures 

The scaphoid is one of eight carpal bones that form the wrist and fractures of this bone are the most common of any carpal bone.  A scaphoid fracture, which is a complete or incomplete break in the bone, occurs when the wrist is hyper-extended past 90 degrees when in radially deviated position.  Fractures of the scaphoid are commonly categorised by their location within the bone with waist fractures being most common followed by those to the proximal and then distal pole.

The blood supply to the scaphoid bone influences healing with fractures at the waist sometimes interfering with the blood supply to the bone.  This may lead to a longer healing time and higher potential for avascular necrosis or death of the bone tissue.

Diagnosis

Diagnosis of a scaphoid fracture is made through gaining an understanding the mechanism of injury, clinical examination and radiographic findings.  A patient with a scaphoid fracture may present with pain in the area of the anatomical snuff box (region just above base of the thumb) and on axial compression of the thumb (i.e. application of a load through the thumb, pushing it toward the wrist).  Standard x-rays may confirm the presence of a fracture however some may be unable to be identified on x-ray, requiring further radiological investigations such as an x-ray two to three weeks following the injury, a bone scan, CT scan or MRI. 

The rate at which a scaphoid fracture heals is dependent on a number of factors including:

Treatment

Conservative management

Stable, non-displaced scaphoid fractures may be treated by casting or immobilisation in a splint / orthosis.  A forearm based thumb spica, as pictured below, is usually required for the first six to 12 weeks following the injury. The period of immobilisation will vary according to the location and is guided by the treating doctor or hand surgeon.

A referral may be made to hand therapy during the early phase of treatment for fabrication of the splint, oedema management and maintenance of range of motion at unaffected joints (i.e. the fingers, elbow and shoulder).  When adequate signs of fracture healing are evident the splint may be removed for hygiene and range of motion exercises to begin with, progressing to strengthening exercises when appropriate.

Surgical management

Surgical repair may be required if the fracture occurs in the proximal pole, is unstable, there is an associated fracture of the distal radius, is more than six to eight weeks old, is displaced greater than 1mm or if fracture angulation is evident. 

Surgical treatment may be completed through the use of percutaneous pins in a closed fashion or via an open reduction and internal fixation (ORIF), generally with a compression screw.  Following surgery a splint can be fitted and is worn until union of the bone occurs.  Mobilisation of the wrist and thumb will generally commence between four to six weeks post surgery.

For further information, regarding this or any other hand therapy intervention, please contact EKCO Hand Therapy on 07 3846 0700.