Scaphoid, being the ‘keystone’ of the carpus linking up proximal and distal carpal rows, is the most commonly fractured carpal bone, with the peak incidence in young active individuals. Its peculiar anatomy, blood supply and orientation create challenges in the diagnosis and treatment of its fracture. Malunited or non-united fractures alter wrist kinematics, resulted in continued wrist pain, stiffness, and early arthrosis.
Most clinical tests showed very high sensitivity but lack specificity individually in diagnosis of scaphoid fracture. Radiographs can sometimes be difficult to interpret due to the orientation and shape of the bone. Early use of advanced imaging like CT or MRI in suspicious cases has been shown to be cost effective when analysing societal cost.
For acute non-displaced fracture, cast immobilisation remained effective, with union rate approaching or exceeding that attained with operative intervention. Evidence support equal outcome when using a short arm or long arm cast with or without the thumb spica component.
Operative treatment is indicated for unstable, displaced or proximal pole fracture. Clinical and biomechanical data support both volar and dorsal approaches as safe and effective. Location of the fracture therefore dictates the surgical approach. Implants providing rigid fixation have evolved from the original solid screw and jig as described by Herbert and Fisher, to various designs of cannulated headless compression screws, or even plates. Anatomic rigid fixation has been shown to lead to faster time to union, reduced risk of non-union, improved functional outcome and earlier return to work.
Minimal invasive techniques, including percutaneous and arthroscopy-assisted techniques, have been developed to better preserve the local vascularity and ligamentous integrity around the scaphoid. Arthroscopy-assisted technique allows better assessment of reduction, fracture stability, vascularity of fracture fragments, associated ligament injury and cartilage status, which can guide subsequent treatment. Bone grafting of reducible non-union can also be performed with such technique.
Various local and free vascularised bone grafting techniques were developed since the 1980s, particularly to address non-unions associated with proximal pole avascular necrosis or failed previous attempted surgical treatment. The use of computer-assisted navigation and robotic assistance for more accurate placement of screw has also been investigated in recent years. However, evidence for recommending these techniques is not strong.
Co-location with:
