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The partial tear of the scapholunate ligament (pre-dynamic stage of SLD) as well as the complete tear (dynamic stage) does not lead to carpal malalignment. However, if the completely ruptured ligament is accompanied by lesions of the extrinsic ligaments, both the scaphoid and the lunate are malaligned already at rest (static stage of SLD). Later, osteoarthritis will develop, beginning in the radioscaphoid compartment, progressing to the midcarpal joint, and ending in a carpal collapse (osteoarthrotic stage of SLD). Dynamic SLD is detectable only in stress views and in cinematography. The high utility of MRI for directly visualizing the injured ligament is emphasized: reparation tissue is focally enhanced at the rupture site by intravenously applied contrast agent; the individual segments of the scapholunate ligament can be visualized in direct MR arthrography, therefore allowing differentiation of partial and complete ligamentous tears.

The lunate may be affected by different pathological states of the wrist. In total, only one quarter of the signal-compromised lunate represented Kienboeck's disease.

Traditionally acute scaphoid fractures were treated by immobilization. As a consequence we have to deal with a high number of scaphoid non-unions or SNAC wrists. A study of 30 patients with scaphoid non-union showed that only 30% (9 patients) have not seen a doctor, while the majority of the patients (70%, 21 patients) were treated by a physician after trauma. In 15 (71.4%) of these 21 patients a missed diagnosis and in 6 (28.6%) a failed conservative treatment of the scaphoid fracture were the reasons for scaphoid non-union. Therefore, improvements in the diagnosis and therapy of scaphoid fractures are urgently needed. Herbert's classification of scaphoid fractures provides the underlying rationale for treatment according to the fracture type seen on X-ray. Differentiation between stable and unstable fractures sometimes is difficult from conventional X-rays. In these cases we recommend a CT bone scan in the long axis of the scaphoid. According to the CT scan we modified Herbert's classification: undisplaced waist fractures are classified as stable and can be treated conservatively or can be stabilized percutaneously using minimally invasive procedures. Comminuted or displaced fractures are classified as unstable and need operative treatment because of the increased risk of scaphoid non-union after plaster immobilization. Fractures of the proximal pole of the scaphoid should be treated operatively by internal fixation, even if they are not displaced, because of the reduced perfusion. We recommend a CT scan of the scaphoid, if there is any doubt about the diagnosis or the stability of the scaphoid fracture. In any case, a CT scan has to be ordered to justify a conservative treatment.