Anatomical Variations That Can Lead to Spine Surgery at The Wrong Level: Part II Thoracic Spine.

Spine surgery at the wrong level is a detrimental ordeal for both surgeon and patient, and it falls under the wrong-site surgery sentinel events reporting system. While there are several methods designed to limit the incidence of these events, they continue to occur and can result in significant morbidity for the patient and malpractice lawsuits for the surgeon. In thoracic spine, numerous risk factors influence the development of this misadventure. These include anatomical variations such as transitional vertebrae, rib variants, hemivertebra, and block/fused vertebrae as well as patient characteristics, such as tumors, infections, previous thoracic spine surgery, obesity, and osteoporosis. An extensive literature search of the PubMed database up to 2019 was completed on each of the anatomical entities and their influence on developing thoracic spine surgery at the wrong level, taking into consideration patient's individual factors. A reliable protocol and effective techniques were described to prevent this error. In addition, the surgeon should collaborate with radiologists, particularly in challenging cases. A thorough understanding of the surgical anatomy and its variants coupled with patients characteristic is crucial for maximal patient benefit and avoidance of thoracic spine surgery at the wrong level.