BACKGROUND: Coronary artery bypass graft surgery (CABG) is an effective and widespread coronary revascularisation technique, nevertheless there are a number of long-term postoperative complications from which patients can suffer. One year after CABG surgery pulmonary function is decreased by 12% and 30% of the patients suffer from chronic thoracic pain. To date and to our knowledge there are no effective treatments for these conditions. The aim of the present clinical trial is to explore the effectiveness of osteopathic treatment on these conditions. METHODS: The study is designed as a randomised controlled trial with two parallel groups. Group A will receive a standard cardiac rehabilitation programme during 12 weeks and group B will receive the same standard cardiac rehabilitation programme supplemented with four osteopathic treatments (OT). OT will be performed at week 4, 5, 8 and 12 after surgery. Three hundred and eight patients (Group A: n = 154, Group B: n = 154) will be enrolled from the cardiothoracic surgery department of the Jessa Hospital Hasselt. Blinding will be assured for the staff of the cardiac rehabilitation centre and outcome assessors. Primary outcome measure will be the mean difference in change from baseline in slow vital capacity (SVC) at 12 weeks after surgery between groups. Secondary outcome measures will be the change from baseline in quality of life, pain, thoracic stiffness and maximal aerobic capacity at 12 weeks after surgery. A follow-up is planned 52 weeks after surgery for SVC, quality of life, pain and thoracic stiffness. Intention to treat analysis will be executed. DISCUSSION: The OstinCare study has been designed to explore the potential long-term added value of osteopathic treatment in the management of decreased pulmonary function, chronic thoracic pain and diminished thoracic mobility after CABG surgery. TRIAL REGISTRATION: The protocol has been retrospectively registered on ClinicalTrials.gov ( NCT01714791 ).