The severity of ulnar variance compared with contralateral hand: its significance on postoperative wrist function in patients with distal radius fracture

The aim of this study was to detect the severity of ulnar variance (UV) compared with contralateral hand on postoperative wrist function in patients with distal radius fracture. 116 cases with unilateral distal radius fracture were retrospectively analyzed and divided into high or low UV severity groups (Dividing value = 2.5 mm). The following parameters were used to evaluate the effect: palmar tilt, radial inclination, VAS score, DASH score and wrist function. The severity of UV existed widely, accounting for 93.1% (108 cases). The severity of UV correlated with palmar tilt, radial inclination, grip strength, VAS score, DASH score and the wrist function (P < 0.05). Log-rank analysis showed that the severity of UV, palmar tilt, radial inclination were important factors influencing the joint function postoperatively (P < 0.0 5). Multivariate analysis confirmed that the severity of UV was an independent and significant factor on wrist function (P = 0.010). And the palmar tilt was also an important factor influencing wrist function (P = 0.047). The severity of ulnar variance compared with contralateral hand is an independent and significant factor on wrist function, which should be considered as an important step during preoperative plan.