26

Discussion

Simple spine surgical procedures such as diskectomies, laminectomies, and one- or two-level fusion operations do not routinely involve significant blood volume loss and, accordingly, perioperative hemostasis is often not a significant issue. However, regardless of the degree of anticipated spine surgical intervention, proper patient positioning remains important to the overall goal of minimizing operative blood and promoting effective hemostasis. The Jackson spinal table leaves the patient’s abdomen free in the prone position and therefore decreases inferior vena cava pressure and, as a result, decreases epidural venous plexus filling.1 Theoretically, this also decreases vertebral venous pressure and thus lowers intraoperative blood loss from decreased bone bleeding.

Intermittent pneumatic compression is instituted perioperatively, as this method has been shown to be as effective as chemical prophylaxis for low-risk spine surgery patients. Patients undergoing simple spine surgery procedures typically ambulate in the early postoperative phase, and thus do not require chemical prophylaxis. Minimally invasive spine surgery techniques have further reduced the degree of postoperative pain typically experienced by patients, allowing for even earlier ambulation and the transition of many simple spine surgery operations to day-surgery procedures. Chemical prophylaxis is only recommended in this patient population if there are other factors that raise the risk of VTE (e.g., previous VTE, malignancy, prolonged recumbency due to perioperative medical complication).

Case 2: Spinal Deformity (Fixed Sagittal Imbalance)

History

A 61-year-old man presented with a multi-month history of severe, progressive ambulatory leg pain radiating to his bilateral calves. This claudicant leg pain was occurring on the background of long-standing worsening chronic mechanical low back pain and a progressive inability to stand in an upright, erect fashion. His past medical history was significant for having undergone a T10–L3 anterolateral fusion (Dwyer procedure) for scoliosis 30 years previously and a myocardial infarction 1 year ago that was treated via percutaneous placement of a bare-metal coronary stent and dual antiplatelet therapy with clopidogrel (Plavix) and aspirin.

Physical examination demonstrated a substantial thoracic kyphosis and lumbar hypolordosis. No focal deficits were identified on a neurologic examination. Standing scoliosis X-rays demonstrated his previous T10–L3 Dwyer fusion construct combined with a severe fixed sagittal imbalance measuring 17.5 cm (Fig. 26.1) as well as significant degenerative disk disease at the L4/5 and L5/S1 levels caudal to the previous fusion. Lumbar spine MRI (Fig. 26.2) revealed severe spinal stenosis both centrally and in the lateral recesses at the L4/5 and L5/S1 levels.

Diagnoses of fixed sagittal imbalance and adjacent segment degeneration spinal stenosis were made. After a lengthy discussion with the patient about the pertinent risks and benefits of surgical intervention, a T3–ilium posterior instrumented fusion in combination with multiple thoracic Smith-Petersen osteotomies, a L2 pedicle subtraction osteotomy, as well as L4/5 and L5/S1 transforaminal lumbar interbody fusions was planned as a treatment for the patient’s fixed sagittal imbalance and spinal stenosis.

Fig. 26.1a,b Standing scoliosis series. (a) Anteroposterior view. (b) Lateral view. The prior anterolateral T10-L3 fusion construct is demonstrated as is the severe sagittal imbalance.