The decision-making process in healthcare systems, especially in the area of surgical management is generally considered to have a low level of transparency; hence, effective decision-making plays a vital role in the case sector. Non-union of a fracture is dependent on many critical causative factors and in the past healthcare management studies, several research activities highlighted the influence of various causative factors on non-union. However, none of the studies neither tried to prioritise the factors nor identified the interrelationship between them. In the present research, through literature review and opinions of seven surgeons' 10 causative factors of non-union were shortlisted and they were analysed and modelled by a multi-criteria decision-making tool. The total interpretive structural modelling (TISM) methodology was used for identifying the mutual relationships among the causative factors and for developing a hierarchical structure. Also, the MICMAC approach was employed to identify the significant/dominant factors. The results of the TISM approach and MICMAC analysis revealed that ‘Alcohol abuse’ was found to be the most significant causative factor followed by ‘use of tobacco’, and ‘inappropriate dynamisation’ was found to be the least important. This study intends to guide the medical practitioners and healthcare managers in understanding the mutual influence of the causative factors and prioritisation of the same. Further, it helps them to carry out the surgical management effectively.