Scaphoid Fracture
Statistically, the scaphoid fracture is the most common type of fracture affecting the wrist bone, with active young men between 20 and 30 years of age making up the majority of those affected. The incidence rate of scaphoid fractures is reported as 30-40 per 100,000 patients, with men more commonly affected than women by a ratio of 5 to 1. The objective when treating scaphoid fractures is to ensure the anatomically correct healing of the bones, to avoid the feared complication known as scaphoid pseudarthrosis and the possible development of wrist arthrosis in the long term.
Scaphoid fractures are normally caused by a fall onto the outstretched hands with the fracture often difficult to identify in the initial x-ray images. This type of injury often happens during football, cycling, skateboarding and snowboarding or other types of physical activity with a risk of falling. Alongside scaphoid fractures, high-speed trauma can lead to luxation of the wrist (carpal dislocation, perilunate fractures/dislocations). The pain caused by the fractures can be very slight. If a patient is not symptom-free 8 to 10 days after a fall, then the possibility of a scaphoid fracture should be considered.
Examination and Diagnosis
Scaphoid fractures present a diagnostic challenge and they are often not initially identified. Therefore, diagnosis should continue until the fracture is confirmed or definitively ruled out. After a wrist trauma, a detailed anamnesis and comprehensive examinations are necessary. If during the clinical examination, preferably by a hand surgeon, there are signs of dorsal tenderness on palpation at the anatomical snuffbox or palmar at the distal pole of the scaphoid, then a scaphoid fracture should be suspected. Often, during the examination, a sprain-like pain is identified in the thumb digit ray.
Following the conventional 2-plane x-ray of the wrist for suspected scaphoid fracture, known as the Stecher method, , we recommend a high-resolution thin layer computed tomography with a layer of between 0.5 and 1 mm (CT) parallel to the long axis of the scaphoid. This will enable the identification of fractures not visible on the x-ray images, and the type of fractures (fracture morphology) visible on the conventional x-ray images can be accurately assessed and the type of treatment (operative or conservative) recommended. The Krimmer-Herbert CT classification is always used to classify stable fractures (A fractures) and unstable fractures (B fractures).
Magnet resonance imaging (MRI) is also a suitable method for the identification of scaphoid fractures. Using the same projection as the CT, the tomography should be carried out using a hand coil.
In the hands of an experienced examiner, ultrasound is also an option to identify scaphoid fractures.
Conservative Therapy
The conservative treatment of fresh scaphoid fractures continues to be based on a commonly used treatment concept. After definitive classification as a non-displaced fracture (A fracture) using high-resolution and thin-layer CT images, a circular forearm cast or circular thermoplastic splint encompassing the thumb metacarpophalangeal joint, fitted by a hand therapist, is sufficient. After 6 weeks, the first follow-up x-ray is necessary using the Stecher method. If ossification is confirmed, hand ergotherapy or physiotherapy can begin. If the fracture is still visible, CT assessment is essential for deciding whether or not to continue with the conservative treatment approach or to change to a treatment regimen involving surgery.
Operative Therapy
Unstable scaphoid fractures (B fractures) should be operatively treated. Cannulated double-threaded screws are usually used. The operative method for bone stabilisation of scaphoid fractures depends on the location of the fracture. In many cases, a minimally invasive technique can be used which then enables early mobilisation of the wrist joint during aftercare. The operative treatment of a scaphoid fracture is technically very demanding and requires an experienced hand surgeon. In certain circumstances, arthroscopic-assisted screw fixation can also be used. With evidence of ossification, the cure rate following operative therapy is between 90 and 100%. The practice founder, Prof. Sauerbier, has shared his years of experience and the results of his scaphoid surgery in many national and international lectures and publications.
Aftercare
Immobilisation is rarely needed following minimally invasive treatment of a scaphoid fracture. The patient must wear an elastic bandage for one week after the operation. Hand therapy can begin on the second day after the operation. The suture material will be removed between days 12 to 14. In the case of open surgery, which is used for major displaced fractures, immobilisation for 6 weeks is necessary using a thermoplastic splint fitted by a hand therapist.
The first follow-up x-ray takes place after 6 weeks and the CT for a final assessment of bone healing after 10 to 12 weeks. After the period of bone consolidation, the wrist can again be actively stressed during physical activities. Patients are able to return to work earlier after operative treatment than after conservative treatment.