Abstract
We aim to assess the AP distance and teardrop angles in a cohort of normal wrists and to assess their possible use as prognostic indicators in fractures of the distal radius.
Two hundred standardised PA and lateral wrist radiographs from uninjured wrists and 95 patients with fractures of the distal radius were assessed and anatomic parameters measured, including the Teardrop angle and AP distance. Clinical assessment at a mean of 6 years post fracture included an assessment of grip strength and range of motion along with the DASH score.
The mean teardrop angle in 200 normal wrists was 68 degrees (95%CI:67–69 degrees) and did not differ significantly between sexes (p=0.148). The average teardrop angle at presentation in 95 fractures of the distal radius was 47 degrees (95%CI:41–50 degrees), improving significantly to 58 degrees (95%CI:56–61 degrees, p< 0.0001) post-reduction, and this improvement was maintained at 56 degrees (95%CI:54–59 degrees) at union. The final position was significantly better than at presentation (p< 0.0001).
Loss of teardrop angle between the fractured and uninjured wrist was significantly related to reduced grip strength (p=0.04) and worse DASH score (p=0.03). The mean AP distance in 200 normal wrists was 19.6mm (95%CI:19.4–19.9mm) in males and 17.6mm (95%CI:17.2–18.0mm) in females, which is significantly different (p< 0.0001). The mean AP Distance at presentation in 95 fractures of the distal radius was 21.0mm (95%CI:20.4–21.7mm), which improved significantly to 19.6 (95%CI:19.1–20.2mm, p< 0.0001), but subsequently worsened to 20.8mm (95%CI:20.2–20.4mm) at union. This is not significantly better than at presentation (p=0.397). An increase in AP distance in the fractured wrist correlated to loss of range of motion (p< 0.01).
The value of these parameters is that they offer quite detailed assessment of the articular surface of the distal radius in the absence of more detailed imaging. They appear to be of prognostic value.
Correspondence should be addressed to Editorial Secretary Mr ML Costa or Assistant Editorial Secretary Mr B.J. Ollivere at BOA, 35–43 Lincoln’s Inn Fields, London WC2A 3PE, England; Email: mattcosta@hotmail.com or ben@ollivere.co.uk
