Modic Changes on Magnetic Resonance Imaging and Smoking History Predict Vascular Adherence During Anterior Lumbar Exposure

Background Anterior approaches to surgically access the lumbar intervertebral discs are associated with a risk of developing major vascular injury and bleeding. The likelihood of injury increases in the presence of dense adherence between the disc annulus, vertebral periosteum, and vessels, which result from reactive inflammatory changes that cause fibrous scarring.

Objective To identify factors that predict vascular adherence, which may facilitate preoperative planning and technique modifications for anterior spine surgery.

Study Design Prospective study examining patients undergoing anterior retroperitoneal exposure for lumbar disc surgery.

Methods A total of 246 consecutive patients were enrolled in this study, all of whom had anterior retroperitoneal exposure for lumbar disc surgery. Patient demographics, smoking status, magnetic resonance imaging (MRI) findings, operative parameters, and dissection difficulty associated with vascular adherence were recorded. Current smokers were defined as those who smoked at the time of surgery or had ceased smoking <6 months before the operation. Patients were excluded if they were morbidly obese or had previously undergone anterior spine surgery or radiotherapy.

Results A multivariate regression analysis identified 2 significant risk factors for difficult dissections that are complicated by vascular adhesion: Modic Type 2 changes on MRI (P = 0.009) and any history of smoking (P = 0.007). Patients with Modic Type 2 changes or a smoking history were 2.1 and 2.2 times more likely to present with vascular adherence, respectively.

Conclusions Modic Type 2 changes on MRI and any smoking history can predict the adherence of large blood vessels to the anterior disc annulus, which enhances the difficulty of the dissection. These predictors could indicate to spinal surgeons that the patient has a 2-fold increased risk of vascular adherence.

Clinical Relevance Modic Type 2 changes on MRI and any smoking history can predict the adherence of large blood vessels to the anterior disc annulus, which enhances the difficulty of the dissection. These predictors could indicate to spinal surgeons that the patient has a 2-fold increased risk of vascular adherence during anterior lumbar exposure.

Level of Evidence 3.