SA Orthopaedic Journal
On-line version ISSN 2309-8309
PIENAAR, G; ANLEY, C and IKRAM, A. Restoration of teardrop angle (TDA) in distal radius fractures treated with volar locking plates. SA orthop. j. [online]. 2013, vol.12, n.3, pp. 32-34. ISSN 2309-8309.
BACKGROUND: Distal radius fractures are among the most common fractures of the upper extremity. Failure to reduce and stabilise the lunate facet fragment intra-operatively has been shown to result in poor functional and radiographic outcomes. Medoff5 introduced the teardrop angle (TDA), which can herald the presence of articular incongruity of the lunate facet. We assess the reduction of the TDA in intra-articular distal radius fractures treated with volar locking plates. METHODS: This was a retrospective review of the pre- and post-operative TDA in two groups of patients. One group had arthroscopy-assisted reduction prior to volar locking plate fixation, while the other had volar locking plate fixation with fluoroscopy alone to guide reduction. We measured the TDA using the 'central axis' method on the standard lateral wrist X-ray as well as the distal radial tilt angles both pre- and post-operatively. RESULTS: In the arthroscopy group, the average pre- and post-surgery TDA was 27° and 43° respectively, while in the fluoroscopy group, the average TDA pre- and post-operatively was 26° and 42° respectively. There was no significance between the two groups (p=0.98) and none of the fractures had a normal TDA post reduction. CONCLUSION: Whichever technique was used to reduce fractures, the average TDA was not restored to normal. The unawareness of this radiological landmark, its measurement and the significance thereof might be the reason for this. Volar tilt angles were restored close to normal values, a parameter that is well known and actively looked at during reduction under fluoroscopy.
Keywords : distal radius fractures; volar locking plates; arthroscopy; lunate facet; teardrop angle.