Dilated Epidural Venous Plexus Causing Radiculopathy: A Report of 2 Cases and Review of the Literature.

BACKGROUND: A dilated epidural venous plexus (DEVP) is a rare cause of radiculopathy, back pain, cauda equina syndrome, and other neurological symptoms. This vascular mass can be secondary to inferior vena cava obstruction, portal hypertension, vascular agenesis, and hypercoagulable states. Although rare, DEVP should be considered in the differential diagnosis for patients who present with lumbar radiculopathy. CASE DESCRIPTION: We present 2 cases involving patients with lumbar DEVP as well as a literature review of the role of hypercoagulability, vascular anatomy, and inferior vena cava thrombosis in the development of DEVP. The first patient had a history of recurrent deep vein thrombosis, systemic lupus erythematosus, and antiphospholipid syndrome. The diagnosis of DEVP was determined after intraoperative biopsy. The patient reported symptom resolution at her 6-month postoperative appointment. The second patient developed DEVP associated with Klippel-Trenaunay syndrome. She presented with back pain and leg weakness, and DEVP was diagnosed via magnetic resonance imaging. A neurosurgeon is currently following the patient. We believe this is the first case of Klippel-Trenaunay syndrome associated with DEVP. CONCLUSIONS: If a patient presents with an enhancing epidural lesion on magnetic resonance imaging and neurological symptoms, DEVP should be considered in the differential diagnosis. Additionally, a search for inferior vena cava thrombosis should be performed as well as risk factors for venous hypertension and hypercoagulable states.

Blood-loss Management in Spine Surgery.

Substantial blood loss during spine surgery can result in increased patient morbidity and mortality. Proper preoperative planning and communication with the patient, anesthesia team, and operating room staff can lessen perioperative blood loss. Advances in intraoperative antifibrinolytic agents and modified anesthesia techniques have shown promising results in safely reducing blood loss. The surgeon's attention to intraoperative hemostasis and the concurrent use of local hemostatic agents also can lessen intraoperative bleeding. Conversely, the use of intraoperative blood salvage has come into question, both for its potential inability to reduce the need for allogeneic transfusions as well as its cost-effectiveness. Allogeneic blood transfusion is associated with elevated risks, including surgical site infection. Thus, desirable transfusion thresholds should remain restrictive.

Acute and Chronic Low Back Pain.

Low back pain is an extremely common presenting complaint that occurs in upward of 80% of persons. Treatment of an acute episode of back pain includes relative rest, activity modification, nonsteroidal anti-inflammatories, and physical therapy. Patient education is also imperative, as these patients are at risk for further future episodes of back pain. Chronic back pain (>6 months' duration) develops in a small percentage of patients. Clinicians' ability to diagnose the exact pathologic source of these symptoms is severely limited, making a cure unlikely. Treatment of these patients should be supportive, the goal being to improve pain and function.

Acute and chronic low back pain.

Low back pain is an extremely common presenting complaint that occurs in upward of 80% of persons. Treatment of an acute episode of back pain includes relative rest, activity modification, nonsteroidal anti-inflammatories, and physical therapy. Patient education is also imperative, as these patients are at risk for further future episodes of back pain. Chronic back pain (>6 months' duration) develops in a small percentage of patients. Clinicians' ability to diagnose the exact pathologic source of these symptoms is severely limited, making a cure unlikely. Treatment of these patients should be supportive, the goal being to improve pain and function.

Biomechanical evaluation of the kinematics of the cadaver lumbar spine following disc replacement with the ProDisc-L prosthesis.

STUDY DESIGN: Biomechanical study of the ProDisc-L in a cadaveric model under pure moment loading. OBJECTIVE.: To determine the kinematic properties of a lumbar spine motion segment and the adjacent level following ProDisc-L disc replacement in the cadaveric spine. SUMMARY OF BACKGROUND DATA: Total disc replacement is intended to preserve native motion, in an attempt to prevent accelerated adjacent segment degeneration. The quality and quantity of the motion following TDR may have important consequences on the facet joints of the same motion segment, as well as the motion at the prosthetic component interface. METHODS: Ten cadaveric lumbar spines were radiographed (L3-L5) and tested under pure moments (+10 Nm to -10 Nm) with an applied follower load (200 N). Load-deformation was tested in flexion/extension, lateral bending (LB), and axial rotation (AR). Range of Motion (ROM) data were recorded. Superior adjacent disc pressure (L3-L4) was measured using subminiature pressure transducers. The L4-L5 disc was subsequently instrumented with a ProDisc-L. Radiographs and biomechanical tests were repeated. RESULTS: Disc replacement significantly reduced extension (ROM 2.2 degrees +/- 0.5 degrees before and 1.2 degrees +/- 0.7 degrees after instrumentation) (P = 0.001), but not flexion (ROM 5.6 degrees +/- 3.1 degrees before and 6.2 degrees +/- 1.2 degrees after) (P = 0.34). Combined flexion/extension motion was marginally reduced (P = 0.517). LB ROM (7.4 degrees +/- 2.0 degrees ) was marginally reduced (P = 0.072) following instrumentation (6.2 degrees +/- 2.5 degrees ), while ROM in AR (3.4 degrees +/- 1.1 degrees ) was significantly increased (4.4 degrees +/- 1.2 degrees ) (P = 0.001). Superior adjacent segment ROM was preserved.No significant differences in disc pressure were observed at the adjacent motion segment before (199 kPa at maximum flexion and 171 kPa at maximum extension) or after disc replacement (252 kPa and 208 kPa, respectively). CONCLUSION: In cadaveric spines, ROM of operated and adjacent motion segments was preserved following ProDisc-L insertion. Excision of the anterior anulus may increase laxity, which is taken up by the restoration of disc height and lordosis, at the cost of a moderate loss of flexion/extension motion. Adjacent segment kinematics were unaffected following TDR.

Lumbar spinal stenosis: indications for arthrodesis and spinal instrumentation.

Surgical indications for simple decompression in patients with lumbar spinal stenosis are well established. Following these guidelines, surgeons can expect good and excellent outcomes in 75% to 90% of patients. Despite the publication of many studies pertaining to the addition of arthrodesis and instrumentation, the indications for adding these procedures to a decompression are much less clear. Preoperative and intraoperative factors must be carefully considered when contemplating the addition of arthrodesis in the setting of spinal stenosis. In patients with preoperative degenerative spondylolisthesis, scoliosis, or kyphosis, and those in whom stenosis develops at a previously decompressed segment, serious consideration should be givenfor inclusion of an arthrodesis. Fusion should also be considered for those patients with stenosis adjacent to a previously fused lumbar segment. Excision of a significant portion of the facet joints or radical excision of the intervertebral disk during the course of the decompression predispose the patient to postoperative instability. The addition of an arthrodesis will likely benefit these patients. Relative indications for the use of spinal instrumentation in the setting of spinal stenosis include correction of deformity, recurrent spinal stenosis with instability, degenerative spondylolisthesis, adjacent segment stenosis with instability, and multiple level fusions.

Anterior cervical approaches for cervical radiculopathy and myelopathy.

Compression of the spinal cord and nerve roots caused by spondylotic changes or disk herniations is the most common etiology for cervical myelopathy, radiculopathy, or myeloradiculopathy. Surgical intervention in treating these conditions has been very successful. Anterior approaches to the cervical spine are being used for the treatment of cervical radiculopathy and myelopathy. The technical aspects of anterior diskectomy and corpectomy, methods of fusion, and the use of instrumentation are important treatment considerations.