Early detection of sternal dehiscence by conventional chest X-ray

BACKGROUND: Diagnosis of sternal dehiscence after sternotomy for cardiac surgery is still made clinically. The aim of this study was to identify radiographic signs of sternal dehiscence by routine chest X-ray (CXR) in patients with and without clinically diagnosed sternal dehiscence. METHODS: 75 patients (group I: 65 +/- 9.3 years, f/m = 12/63) with clinically diagnosed sternal dehiscence, necessitating surgical revision and 75 patients with uneventful sternal healing (matched to group I by age, sex, preoperative risk factors and surgical procedures; group II: 66 +/- 9.0 years, f/m = 12/63) were included in this study. Serial CXRs immediately after surgery until re-intervention or discharge were analyzed by a radiologist, blind to the date of redo surgery. RESULTS: In 39 patients of group I (52%) vs. 8 (10.7%) in group II, abnormalities in the sternal wire and/or a midsternal stripe could be found (p < 0.0001): rotated wires (p = 0.003), shifted wires (p = 0.043), and ruptured wires (p = 0.312). Seven patients presented with combined wire abnormalities in group I vs. 0 in group II. Midsternal stripe sign could be detected in 26 patients of group I vs. 3 in group II (p < 0.0001). Sternal dehiscence was suspected based on the above mentioned abnormalities as early as three days postoperatively (Q1 = 2; Q3 = 8 days) in 39 patients, whereas clinical diagnosis of sternal dehiscence was delayed up to ten days postoperatively (Q1 = 7; Q3 = 13 days). CONCLUSIONS: Radiographic signs of sternal dehiscence could be detected before the clinical diagnosis was apparent and predicted sternal dehiscence in more than half of the patients.