Cultured, Autologous Nucleus Pulposus Cells Induce Functional Changes in Spinal Nerve Roots
Satoru Kayama, Kjell Olmarker, Karin Larsson, Eva Sjögren-Jansson, Anders Lindahl, and Björn Rydevik

Epidural application of nucleus pulposus cells and cell membranes induced a reduction of nerve conduction velocity in the adjacent nerve roots, which indicates that this reduction is related to membrane-bound structures of the nucleus pulposus cells.

A Comparative Immunohistochemical Study of Inflammatory Cells in Acute-Stage and Chronic-Stage Disc Herniations
Aklilu Habtemariam, Mats Grönblad, Johanna Virri, Seppo Seitsalo, and Erkki Karaharju

Inflammatory cells were analyzed in two comparable groups of acute and chronic intervertebral lumbar disc herniation. Supporting results from previous studies, macrophages were more prevalent than T lymphocytes and B cells. No major differences in the occurrence of inflammatory cells in cases of acute and chronic disc herniations were observed.

The Stiffness of Lumbar Spinal Motion Segments With a High-Intensity Zone in the Anulus Fibrosus
Timothy A. Schmidt, Howard S. An, Tae-Hong Lim, Bruce H. Nowicki, and Victor M. Haughton

Biomechanical and anatomic studies of the lumbar spine show that a radial tear of the anulus fibrosus is associated with decreased stiffness in the motion segment, especially with an axial torque.

Current Management of Pediatric Atlantoaxial Rotatory Subluxation
Brian R. Subach, Mark R. McLaughlin, A. Leland Albright, and Ian F. Pollack

A retrospective review of the cause, initial symptoms, diagnosis, and treatment of 20 children with atlantoaxial rotatory subluxation. Available treatment methods are compared, including simple cervical immobilization, traction reduction, and surgical fusion. Clinical outcomes of various treatment options are assessed, risk factors are defined for recurrence, and indications are provided for surgical intervention.

The Natural History of the Cervical Foramen in Symptomatic and Asymptomatic Individuals Aged 20-60 Years as Measured by Magnetic Resonance Imaging: A Descriptive Approach
S. Craig Humphreys, Scott D. Hodges, Avinash Patwardhan, Jason C. Eck, Laurie A. Covington, and Mark Sartori

This study identified normal morphologic evolution in the bony foramen of asymptomatic people compared with that in symptomatic people. Foraminal measurements were larger in asymptomatic people. Widths decreased with age and limited the available area for the exiting nerve root. These normal morphologic changes predispose people to stenosis and thus to radiculopathy.

Correlation Between Health Outcome and Length of Hospital Stay in Lumbar Microdiscectomy
Thomas R. Lorish, Calvin T. Tanabe, Frederick T. Waller, Marla R. London, and David J. Lansky

Increased managed care has created greater pressure to demonstrate effective management of health care resources. In this study, patients' self-reported health status and satisfaction were used to demonstrate that reducing hospital length of stay for lumbar microdiscectomy does not adversely affect patient-perceived quality and satisfaction.

Vertebral Pseudarthrosis in the Osteoporotic Spine
Kazuhiro Hasegawa, Takao Homma, Seiji Uchiyama, and Hideaki Takahashi

Radiologic, operative, and histologic findings of intravertebral cleft in the osteoporotic spine are reported. The unstable intravertebral cleft in the osteoporotic patient with magnetic resonance findings of low intensity on the T1-weighted scans and high intensity on the T2-weighted scans indicates that the cleft is vertebral pseudarthrosis, which forms after a fracture caused by bone insufficiency.

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

It has been increasingly accepted that smoking causes low back pain and that cessation of smoking will reduce the pain. According to the results in this large study, there is a clear link between smoking and low back pain, particularly pain of long duration, but this link is highly unlikely to be causal. It is therefore unfair to hold smoking patients responsible for their low back pain, telling them that smoking causes their pain and abstinence will improve their condition.

Symptom Provocation of Fluoroscopically Guided Cervical Nerve Root Stimulation: Are Dynatomal Maps Identical to Dermatomal Maps?
Curtis W. Slipman, Christopher T. Plastaras, Randal A. Palmitier, Christopher W. Huston, and Elliot B. Sterenfeld

In 87 subjects, 134 cervical nerve root stimulations were performed to document the distribution of pain and paresthesias that resulted. The results were compared with published dermatomal maps and may suggest that cervical dermatomal mapping is inaccurate or the distribution of referred symptoms (dynatome) from cervical root irritation is different than the sensory deficit outlined by dermatomal maps.