Ruptur des skapholunären Interkarpalbands

Locking plate osteosynthesis of scaphoid nonunion with severe bone defects: a case series

The treatment of scaphoid nonunion can be challenging with increasing defect size. We evaluated the outcome of scaphoid nonunion with a substantial bone defect treated with a multidirectional locking plate combined with cancellous bone grafting only. Thirteen patients with significant osseous defects measuring 6 mm or more suffering from primary nonunion without treatment (n = 6) or recalcitrant nonunion following Herbert screw osteosynthesis (n = 7) were treated and reviewed retrospectively. The stabilization was performed after debridement, autologous cancellous bone grafting and volar locking plate osteosynthesis. After a mean follow-up period of 12 months, 12 of the 13 patients achieved successful unions with a free range of motion and complete remittance of pain in everyday activity. The mean scapholunate angle decreased from 59.7° ± 11 to 43.9° ± 5 (effect strength d:1.7, p < 0.00001), scaphoid humpback deformity angle from 58.9° ± 8 to 45.1° ± 8 (d:1.8, p < 0.0001), whereas strength of the injured hand increased from 36.4 kg ± 10 to 42.4 kg ± 9 (d:1.4, p < 0.0001). One nonunion persisted without fragment dislocation receiving revision after 1 year. Thus, locking plate osteosynthesis with cancellous bone grafting is a valid alternative in scaphoid nonunions with extensive bone defects. Additionally, stable retention of the fragments prevents dislocation even in delayed or persistent nonunion. Further prospective studies are required to confirm these findings.

[What does the hand surgeon expect from the radiologist in diagnostic imaging of the hand?]

BACKGROUND

For hand surgeons, in addition to anamnesis and clinical examination, imaging is the essential component in diagnostics and the basis for therapy planning. The focus on the special field of the "hand" and the adjacent joints is limited with regard to the anatomical extent, but with regard to the possible clinical pictures it encompasses the entire range of pathological changes.

CLINICAL ISSUE

Which imaging techniques support the goal of maintaining the functionality of the hand?

PERFORMANCE

The carpal bones can be represented by computer tomography without superimposition. The navicular (scaphoid) should be evaluated sagittally in its longitudinal axis. MRI imaging is useful, for example, when assessing possible ligament injuries or ulnar-carpal complaints on the triangular disc. Stress images prove additional information in the case of of dynamic ligament or joint instabilities.

ACHIEVEMENTS

Imaging with conventional X‑rays is the basis of radiological diagnostics of the hand. In addition, the small structures of the hand and fingers to be assessed must be specifically visualized.

PRACTICAL RECOMMENDATION

In order to enable precise assessment of the fine and complex structures on the hand in relation to the clinical complaints, close communication of the anamnesis and questions with the radiologist is desirable.

[Fractures of the carpal bones without the scaphoid bone]

With the exception of the relatively frequent fractures of the scaphoid bone, isolated fractures of individual carpal bones are rare. Because these injuries are uncommon and because of the complex anatomy and function of the carpus, treatment of carpal bone fractures can be challenging. Carpal bone fractures generally occur in young, sports active and professional patients, can be easily overlooked in plain radiographs and are frequently associated with ligamentous instability, neurovascular injuries and tendon lesions. Small posttraumatic alterations of the precisely aligned carpal structure can cause chronic pain and functional impairment. Therefore, if a wrist fracture is suspected a thorough clinical examination and appropriate differentiated imaging is always necessary, at the end of which a fracture can be excluded or an appropriate conservative or surgical treatment is initiated, with the aim of restoration of carpal anatomy and function.