Commentary on four recently published papers on chronic pain and spinal surgery.

This commentary evaluates four articles dealing with chronic pain from very different perspectives. The first paper by Tsantoulas and McMahon entitled "Opening paths to novel analgesics: the role of potassium channels in chronic pain" evaluates the membrane neurochemistry of the neural cells governing the transmission of pain impulses in the spinal cord and trigeminal systems. As potassium membrane potentials diminish excitability in the nociceptive pain pathways, damage to these pathways may result in excessive transmission of impulses that contribute to "chronic pain". Haneder et al. analyzed degeneration in lumbar discs utilizing 23Na magnetic resonance (MR) imaging to determine whether this would help analyze low back pain versus standard 1H MR imaging. As degenerated discs lose glycosaminoglycan, which attracts 23Na, this imaging could potentially be useful in detecting degenerating intervertebral discs. Mroz et al. analyzed how 445 spinal surgeons handled recurrent lumbar discs (first and second recurrences) herniations in the United States. Surgeons in practice for more than 15 years were more likely to select simple disc revision, while those with fewer years experience and performing more than 200 cases per year were more likely to select revision surgery that included some form of inter-body fusion. Lee et al. performed a multivariate analysis of more than 1532 patients to validate a predictive model of the risk of surgical site infection after various spine surgeries. Outcomes analyzed the frequency of reoperations for irrigation/debridement, and evaluated how patients' comorbidities helped predict the risk of infection (e.g. obesity, rheumatoid arthritis, and the number of levels/extent of surgery).