Neovascularization of Nucleus Pulposus: A Diagnostic Feature of Intervertebral Disc Prolapse
Radha R. Pai, Bouvier D'sa, Coimbatore V. Raghuveer, and Asha Kamath

Histologic comparison was made of material from prolapsed intervertebral discs and material from normal discs in a cadaveric study.

Markers of Nerve Tissue Injury in the Cerebrospinal Fluid in Patients With Lumbar Disc Herniation and Sciatica
Helena Brisby, Kjell Olmarker, Lars Rosengren, Claes-Göran Cederlund, and Björn Rydevik

Four markers of nerve and glial cell injury were studied in the cerebral spinal fluid in patients with lumbar disc herniation. Elevated levels of neurofilament protein and S-100 protein were observed. The results indicated that nerve injury in patients with disc herniation and sciatica includes axonal damage and Schwann cell injury.

New In Vivo Measurements of Pressures in the Intervertebral Disc in Daily Life
Hans-Joachim Wilke, Peter Neef, Marco Caimi, Thomas Hoogland, and Lutz E. Claes

Intradiscal pressure measurements were obtained in one volunteer as he performed activities normally found in daily life, sports, and spinal therapy. Good correlation with Nachemson's data was found in many but not all exercises. Some physiotherapy methods were validated, but others should be reviewed. These measurements substantially increase the data available on intradiscal pressure in varied circumstances.

Motion Analysis of Cervical Vertebrae During Whiplash Loading
Koji Kaneoka, Koshiro Ono, Satoshi Inami, and Koichiro Hayashi

Cervical vertebral motions during simulated rear-end car collisions were recorded by cineradiography and analyzed. The torso forced movements in the cervical spine that were markedly different from normal motion. This motion may be involved in the mechanism of whiplash injury.

Point of View
Nikolai Bogduk

Efficacy of Magnetic Resonance Imaging in the Evaluation of Posterior Cervical Spine Fractures
Gregg R. Klein, Alexander R. Vaccaro, Todd J. Albert, Mark Schweitzer, Diane Deely, David Karasick, and Jerome M. Cotler

A retrospective study was conducted using two independent, blinded musculoskeletal radiologists to evaluate the sensitivity, specificity, and predictive value of cervical spine magnetic resonance imaging to detect posterior element fractures.

Low Back Pain and Lifestyle. Part II--Obesity: Information From a Population-based Sample of 29,424 Twin Subjects
Charlotte Leboeuf-Yde, Kirsten Ohm Kyvik, and Niels Henrik Bruun

Obesity is one of several lifestyle factors that is suspected of causing low back pain. A cross-sectional study of a large population-generated sample of twins showed that obesity is modestly positively associated with low back pain, but that there is no further evidence of causality. The possibility that obesity causes chronic low back pain requires further study.

Risk Factors and Precipitating Neck Movements Causing Vertebrobasilar Artery Dissection After Cervical Trauma and Spinal Manipulation
Scott Haldeman, Frank J. Kohlbeck, and Marion McGregor

A detailed review was conducted of case reports on vertebrobasilar artery dissection occurring after cervical manipulation, major trauma, minor trauma, or routine head movements and those reported as spontaneous. Attempts were made to isolate the patient at risk and the type of neck movement or manipulation that precipitates these dissections.

Proximal Kyphosis After Posterior Spinal Fusion in Patients With Idiopathic Scoliosis
Guy A. Lee, Randal R. Betz, David H. Clements III, and Gail K. Huss

A retrospective study was conducted to determine the prevalence and possible causes of proximal kyphosis after a posterior spinal fusion in patients with idiopathic scoliosis. At 2-year follow-up, 46% of the patients had significant proximal kyphosis between T2 and the fusion mass.

Contralateral Recurrent Lumbar Disc Herniation: Results of Discectomy Compared With Those in Primary Herniation
Gianluca Cinotti, Stefano Gumina, Giuseppe Giannicola, and Franco Postacchini

Patients undergoing discectomy for contralateral recurrent lumbar disc herniation were observed prospectively from the time of recurrence of symptoms. Clinical evaluation 2 years after reoperation showed that, after contralateral discectomy, pain severity, patient satisfaction, functional outcome, and work status were similar to those reported after primary disc excision.

Variability of Outcome After Lumbar Disc Surgery
Chris Woertgen, Ralf Dirk Rothoerl, Kerstin Breme, Juergen Altmeppen, Matthias Holzschuh, and Alexander Brawanski

Outcome after after lumbar disc surgery was traced through three follow-up examinations to determine whether outcome status changes during follow-up. Forty percent of the patients showed a change in outcome at different follow-up times.

External Iliac Artery Occlusion in Posterior Spinal Surgery
Shigeo Akagi, Yugo Yoshida, Ishashi Kato, Kunihiko Sasai, Takanori Saito, Atsushi Imamura, and Ryokei Ogawa

Prolonged direct pressure on the inguinal region during posterior spinal surgery on a Hall frame may cause external iliac artery occlusion in certain situations. Early recognition and adequate treatment of this complication can prevent serious sequelae.