No abstract

Study design: Intrathecal administration of 4-aminopyridine (4-AP) in chronic spinal cord injured (SCI) patients. Objective: To determine the safety and e ects of intrathecal administration of 4-AP in a small population of chronic SCI patients. Setting: The post anesthesia care unit of a tertiary care hospital. Methods: Following animal mode studies to establish dosing safety, six subjects with chronic SCI were examined. In each subject, an intrathecal catheter was placed with the tip as close to the lesion level as possible. 4-AP was infused at 5 mg/h for a period of 4 ± 5 h. Vital signs were recorded and sensory-motor physical examinations and pain questionnaires were administered for 24 h. In two patients, samples of cerebrospinal¯uid for analysis were drawn from a second intrathecal catheter. Results: No adverse systemic side e ects were noted. One patient showed transient improvement in sensory function; two showed transient increases in spasticity; three showed transient increases in cutaneomuscular re¯exes and two showed an apparent small increase in volitional motor control. The concentration of 4-aminopyridine in the cerebrospinal¯uid reached a peak of 163 ng/ml at 4 h in one subject and 122 ng/ml at 5 h in the other subject examined. Conclusion: Intrathecal administration of 4-aminopyridine at a rate of 5 mg/h does not appear to cause adverse e ects and may modify spinal cord function. This route of administration allows local cerebrospinal¯uid concentrations equivalent to those produced by maximum tolerable systemic doses, which require 1000 times more drug substance to be delivered to the subject as a whole. Intrathecal administration o ers the potential to focus therapeutic e ects to the lesion site while minimizing systemic side e ects. Spinal Cord (2000) 12, 728 ± 732

Study design: A prospective double blind cross over trial of intravenous 4-Aminopyridine (4-AP). Objective: To determine the ecacy of this drug in the treatment of spinal cord injured (SCI) patients for neurologic impairment, pain and spasticity. Setting: The post anesthesia care unit (PACU) of a tertiary care acute hospital. Methods: Twelve paraplegic patients were enrolled in a double blind cross over intravenous trial of 4-Aminopyridine (4-AP). Thirty milligrams of 4-AP or placebo were administered over a 2 h period. Patients were serially examined during and after the infusion clinically for pain, sensorimotor function, hypertonicity and motor control using electromyography (EMG). Samples of blood and cerebrospinal¯uid (CSF) were also analyzed at similar intervals. Results: Despite penetration of 4-AP into the CSF, no signi®cant dierences were noted in the clinical and EMG parameters at the times measured. Individual changes in sensory function were reported by some patients in both the placebo and 4-AP trials, however mean values were not robust. Frequently, patients complained of unpleasant symptoms during the 4-AP infusion. Conclusion: The intravenous route may not be the best way to administer this drug as no short term bene®ts were observed. Spinal Cord (2000) 38, 7 ± 15

The sacroiliac joint as a source of chronic pain has been a subject of debate for a long period of time. This controversy stems from the inherent anatomic location of the sacroiliac joint. Adjacent spinal structures may cause pain to be referred to the sacroiliac joint, thus making a precise diagnosis difficult. The most reliable method to establish the diagnosis of sacroiliac arthralgia is fluoroscopic-guided intra-articular injection of a local anesthetic preceded by a sacroiliac arthrogram. Although there are many therapeutic options for sacroiliac joint syndrome, the ideal treatment has not yet been discovered. There is evidence that intra-articular viscosupplementation of the sacroiliac joint with hylan can consistently and reliably induce a prolonged analgesic response in sacroiliac joint syndrome. Viscosupplementation restores joint homeostasis, allows increased joint motion, and induces analgesia. Hylan is highly viscoelastic hyaluronan (hyaluronic acid), and is capable of increasing the viscoelastic properties of synovial fluid.

No abstract

Morphine, applied by microiontophoresis to functionally identified dorsal horn neurones in segments L5–L7 of cats (chloralose anaesthetized, decerebrated or high spinal), produced primarily a depression of the discharge of neurones responding to noxious radiant heat applied to the skin. It depressed on-going activity (12 out of 20 neurones), glutamate-evoked excitation (8/8) and the response to the noxious stimulus (13/21). The response of two additional neurones to heat was potentiated. The effects began 10–30 s from the onset of application, reached a maximum in up to 8 min and outlasted application by up to 10 min. Morphine had relatively little effect on on-going activity and glutamate-evoked excitation of neurones responding to non-noxious stimuli (n = 18). Naloxone (intravenously and iontophoretic) reversed these depressions (4/11). It is suggested that morphine may produce analgesia, at least in part, by a direct action on a specific morphine receptor in the spinal cord.

Two cases of refractory sacroiliac joint pain are reported that were managed with permanently implanted neuroprostheses at the third sacral nerve roots. The authors suggest that neuroaugmentation can be a reasonable option in selected patients with refractory sacroiliac pain.

The use of CT to guide the procedure allowed precision in performing the procedure and in making a differential diagnosis.