Scapholunate Dissociation clinical trials

Intraoperativ Testing of Scapholunate Instability in Radius Fracture

Ligamental side injuries in distal radius fractures are not uncommon, but diagnosis is often difficult. Diagnosis with the simultaneous presence of a fracture is not very reliable and usually highly subjective. 5-64% of radius fractures are accompanied by injuries of the scapholunary ligament (SL). Intra-articular radius fractures have a significantly higher prevalence for SL dissociation, due to a greater energy transfer to the hand roots. In 5-10% of cases, distal, intra-articular radius fractures are associated with complete ruptures of the dorsal scapholunary band. The number of untreated SL band lesions in distal radius fractures is largely unknown. If left untreated, scapholunary ligament lesions, with the simultaneous presence of a rupture of the dorsal ligament, (DIC) can lead to symptomatic carpal instability, therefore the correct diagnosis and adequate therapy is necessary even in the presence of a distal radius fracture. Through the band ruptures, both the Os lunatum and the Os scaphoideum experience irregular motion. This leads to Dorsal Intercalated Segment Instability (DISI) and is reflected by the flexion of the os scaphoideum and the extension of the os lunatum radiologically in the lateral uptake with an increase of the scapholunary angle > 60° (usually maximum 45)° and the radioscaphoidal angle >15°. An incorrect use can lead to the development of SLAC-wrist (Scapho-Lunate Advanced Collapse) over years, this risk should be reduced if possibel by recognizing the original injury. With regard to this problem, we would like to establish a radiological, dynamic functional test, allowing scapholunary ligament lesions in distal radius fractures to be diagnosed intraoperatively.