Incidence of deep vein thrombosis and the diagnostic values of The Risk Assessment Profile for Thromboembolism and D-dimer in patients with peri-ankle fracture

Abstract

Objective To investigate the factors associated with the incidence of deep vein thrombosis (DVT) and the diagnostic values of The Risk Assessment Profile for Thromboembolism (RAPT) and D-dimer in the patients with peri-ankle fracture. Methods Enrolled in the study were 85 patients with peri-ankle fracture who had been treated from August 2014 to March 2015. They were 51 males and 34 females, with an average age of 44.0 years (from 16 to 79 years). They were grouped according to the presence or absence of DVT and the RAPT scores before and after surgery as well. The patients with RAPT≤5 were assigned into the low risk group and those with RAPT > 5 into the medium-high risk group. The D-dimmer levels were examined for all the cases on the second day after admission, the day before surgery, the first, third, and fifth days after surgery. Results In this cohort, DVT occurred in 21 cases. Fifteen occurred before surgery (17.6%),with 13 at the distal ends and 2 at the proximal ones. Seven cases disappeared after surgery. The postoperative DVT was found in 14 cases (16.5%). All of them involved the distal end and 6 were new. Compared with the non-DVT group, the patients in the DVT group were significantly older and had significantly more high-energy injuries (P < 0.05) . The preoperative incidence of DVT was significantly higher in the medium-high risk group (22.4%) than in the low risk group (0% ) (P = 0.033); the postoperative incidence of DVT was insignificantly higher in the medium-high risk group (19.4%) than in the low risk group (0%) (P = 0.114). The value of D-dimmer was increased in 65 cases (76.5%) on the second day after admission, in 62 cases (73. 0% ) on the day before surgery, in 71 cases (83. 5%) on the first day after surgery, in 77 cases (90.6% ) on the third day after surgery, and in 80 cases (94.1%) on the fifth day after surgery. When the D-dimer critical value was 1.4 mg/L, its sensitivity was 0.875 and its specificity 0.043 in the diagnosis of DVT; when the D-dimer critical value was 3.6 mg/L, its sensitivity was 0.810 and its specificity 0.578 in the diagnosis of DVT. Conclusions Perioperative DVT may happen in the patients with peri-ankle fracture, mostly involving the distal end. The incidence of DVT may be associated with the patient's age and injury violence. RAPT may have a certain degree of predictive value for preoperative incidence of DVT but may be of little value for prediction of postoperative DVT. The appropriate critical value of D-dimer may be 3.6 mg/L because the critical value of 1.4 mg/L results in poor accuracy and specificity in diagnosis of DVT in the patients with peri-ankle fracture. Key words: Ankle joint; Fractures, bone; Venous thrombosis; Risk Assessment Profile for Thromboembolism; D-dimer