Intraoperativ Testing of Scapholunate Instability in Radius Fracture

Summary

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.

Conditions

• Radius; Dislocation Distal
• Scapholunate Dissociation

Interventions

DIAGNOSTIC_TEST

dynamic functional testing

First, with an arthroCT of the wrist by intraarticular injection of contrast agent, a possible scaphulonary band lesion is detected. The surgeon does not yet know the findings of the possible ligament injury at this time, but he can assess the fracture in the CT. Subsequently, a dynamic functional test of the scapholunary distance is carried out intraoperatively under investigation with the modified Watson test before and after performing the osteosynthesis. For this purpose, the wrist is intraoperatively brought under pull on the thumb from a radial abduction into an ulnarabduction. In the presence of a scapholunary instability, a change in the distance of the scapholunary joint gap is shown here under illumination. Now the surgeon receives the finding of the Arthro-CT regarding an existing ligament injury. If necessary, this is treated in the same anaesthetic with a band seam and ossary transfixation.

Sponsors & Collaborators

• AO Research Institute Davos

  collaborator OTHER

• Spital Davos AG

  lead NETWORK

Principal Investigators

• Michael Villiger · Spital Davos

Study Design

Allocation

NA

Purpose

DIAGNOSTIC

Masking

NONE

Model

SINGLE_GROUP

Eligibility

Min Age

16 Years

Max Age

80 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2020-10-01

Primary Completion

2022-10-31

Completion

2022-10-31

Countries

• Switzerland

Study Locations