Physiotherapy for anterior knee pain: a randomized controlled trial. (City Hospital Nottingham, Nottingham, United Kingdom) Ann Rheum Dis 2000;59:700–704.

This observer blind, prospective, factorial design randomized controlled trial determined the efficacy of the individual components of physiotherapy in subjects with anterior knee pain. Eighty‐one young adults with anterior knee pain were randomly allocated to one of four treatment groups: (1) exercise, tapping, and education; (2) exercise and education; (3) taping and education; and (4) education alone. Each group received 6 physiotherapist‐led treatments over 3 months. Follow up took place at 3 months using the following outcomes measures: Patient satisfaction; a visual analogue pain score; the WOMAC lower limb function score; the Hospital Anxiety and Depression scale (HAD); and quadriceps strength. At 12 months the WOMAC and HAD were assessed by postal questionnaire. All groups showed significant improvements in WOMAC, visual analogue, and HAD scores; these improvements did not vary significantly between the four groups or between exercising/nonexercising and taped/nontaped patients at 3 and 12 months. However, patients who exercised were significantly more likely to be discharged at 3 months than nonexercising patients. Taping was not significantly associated with discharge. Significantly greater improvements in WOMAC, visual analogue, and the anxiety score were seen in patients who were discharged than in those who were referred. Conclude the proprioceptive muscle stretching and strengthening aspects of physiotherapy have a beneficial effect at 3 months sufficient to permit discharge from physiotherapy. These benefits are maintained at 1 year. Taping does not influence the outcome. Comment by Phillip S. Sizer Jr., MEd, P.T. The investigators evaluated a total of 81 patients (36 female and 45 male) between the ages of 16 and 40 years with a history of anterior knee pain of more than three months. Patients were evaluated through history, locomotor examination, WOMAC score and Hospital Anxiety and Depression scale (HAD). In addition, isometric quadriceps strength and power were measured before and after treatment. Patients were randomly assigned to one of four different groups: (1) exercise, taping, and education; (2) taping and education; (3) exercise and education; and (4) education alone. Each patient received six treatments over a three‐month period. Through a 2 × 2 factorial analysis design, the investigators discovered that the group participating in exercise were significantly more likely to be discharged than non‐participants. Additionally, they found that taping alone was not significantly associated with discharge. Furthermore, they observed no difference between groups for the WOMAC score and the visual analogue pain score. Finally, they found that education alone resulted in the sufficient improvement of 60% of those subjects without need for other intervention, supporting the value of therapist contact and simple advice. These investigators embarked upon the evaluation of a controversial condition whose etiology is not well understood.¹ Recent investigators have revealed alternative explanations for persistent anterior knee pain, including increased patelo‐femoral joint stress^2,3 and receptor neuro‐sensitization within the lateral retinaculum.⁴ These outcomes may reflect the influence of exercise on those factors and support the use of physical therapy in the treatment of anterior knee pain.     

Periradicular infiltration for sciatica: a randomized controlled trial. (University Hospital of Oulu, Helsinki, Finland). Spine. 2001;26:1059–1067.

In this study, 160 consecutive, eligible patients with sciatica who had unilateral symptoms of 1 to 6 months duration, and who never underwent surgery were randomized for a double-blinded injection with methylprednisolone bupivacaine combination or saline. Objective and self-reported outcome parameters and costs were recorded at baseline, at 2 and 4 weeks, at 3 and 6 months, and at 1 year. Recovery was better in the steroid group at 2 weeks for leg pain, straight leg raising, lumbar flexion, and patient satisfaction. Back pain was significantly lower in the saline group at 3 and 6 months. Sick leave and medical costs were similar for both treatments, except for cost of therapy visits and drugs at 4 weeks, which were in favor of the steroid injection. By 1 year, 18 patients in the steroid group and 15 in the saline group underwent surgery. Conclude improvement during the follow-up was found in both the methylprednisolone and saline groups. The combination of methylprednisolone and bupivacaine seems to have a short-term effect, but at 3 and 6 months, the steroid group seems to experience a "re-bound" phenomenon.     

Oral therapy for migraine: Comparisons between rizatriptan and sumatriptan. A review of 4 randomized,double‐blinded clinical trials. (University of Copenhagen,Glostrup, Denmark) Neurology 2000;55:S19–S24.

Four comparative, placebo-controlled, randomized clinical trials of oral rizatriptan versus oral sumatriptan including one Phase II trial and three Phase III trials were reported in this study. Forty mg rizatriptan was found to be more effective than 100 mg sumatriptan, but was associated with a high incidence of adverse effects. Five mg rizatriptan was comparable to 50 mg sumatriptan. In two trials, rizatriptan 10 mg, the recommended dose in most countries, had a more rapid onset of action than 50 mg and 100 mg of sumatriptan. In addition, 10 mg of rizatriptan resulted in more patients being pain-free after 2 h than 100 mg of sumatriptan, and resulted in fewer drug-related adverse events than sumatriptan.     

Ability of anaesthetists to identify a marked lumbar interspace. (Nuffield Department of Anaesthetics, John Radcliffe Hospital, Oxford, United Kingdom) Anaesthesia 2000;55:1122–1126.

This article assessed anesthetists' ability to identify correctly a marked lumbar interspace in 100 patients undergoing spinal magnetic resonance imaging scans. Using ink, the first anesthetist marked an interspace on the lower spine and attempted to identify its level with the patient in the sitting position. The second anesthetist attempted to identify the level with the patient in the flexed lateral position. A marker capsule was taped over the ink mark and a routine scan performed. The actual level of markers ranged from 1 space below to 4 spaces above the level at which the anesthetist believed it to be. The marker was 1 space higher than assumed in 51% of cases and was identified correctly in only 29%. Accuracy was unaffected by patient position (sitting or lateral), although it was impaired by obesity and positioning of the markers high on the lower back. The spinal cord terminated below L₁ in 19% of the patients. This, together with the risk of accidentally selecting a higher interspace than intended for intrathecal injection, implies that spinal cord trauma is more likely when higher interspaces are selected. Comment by Alan Kaye, M.D. Previous studies have demonstrated inaccuracies regarding identification of lumbar interspaces. This study by Broadbent et al involved 104 patients scheduled for lumbar magnetic resonance imaging and essentially anesthesiologists were asked to mark with washable ink the skin overlying any interspace on the lower spine after palpation of the lumbar region. Different positions were evaluated including sitting and lateral. Only 29% were demonstrated to be correct through magnetic resonance imaging. Within the lumbar region, there were tremendous errors by the anesthesiologist at all levels. Further, a common mistake included the assumption of location based on the landmark provided from the iliac crest. Therefore, with the potential of neurological damage from misidentification of the vertebral column, the authors recommend lower rather than higher sites when more than 1 site is identified. The authors provide a clever investigation; however, this is a relative small study population and there is little mention of the variation existing within the population studied. However, this study suggests that if an option exists as to which lumbar space to enter, the lower would seem safer and more prudent to minimize the potential of neurologic injury.     

Memantine (a N-methyl-d-aspartate receptor antagonist) in the treatment of neuropathic pain after amputation or surgery: a randomized, double-blinded, cross-over study. (Danish Pain Research Center, University of Aarhus, Aarhus, Denmark) Anesth Analg 2000;91:960–966.

Evidence has accumulated that the N‐methyl‐d ‐aspartate receptor system plays a role in continuous and stimulus‐evoked pain after nerve injury. The analgesic effect of memantine on a group of patients with chronic pain after surgery was examined in this randomized, double‐blinded, study. Nineteen patients randomly received either memantine or placebo in the first 5‐week treatment period. A washout period of 4 weeks was followed by another 5‐week treatment period of the opposite drug. The dosage of drug was increased from 5 to 20 mg/d. Pain was recorded daily, with the use of a 0‐10 numeric rating scale. Before and at the end of each treatment, pain and sensitivity were also assessed by using the McGill Pain Questionnaire, allodynia to touch, brush, and cold, wind‐up‐like pain, and thresholds to mechanical stimuli (pressure and von Frey hair). A total of 15 patients completed the study. There was no difference between memantine and placebo on any of the outcome measures. Conclude that memantine at a dosage of 20 mg/d does not reduce spontaneous or evoked pain in patients with nerve injury pain. Comment by Tat‐Leang Lee, M.D. The treatment of patients suffering from chronic neuropathic pain remains a clinical challenge, particularly in cases where opioid therapy fails to provide sufficient pain relief. Experimental data concerning the role of NMDA‐mediated processes in central sensitization and the effects of NMDA receptor antagonists in different models of neuropathic pain have been well established. Currently, clinically available NMDA antagonists have narrow therapeutic windows and are limited by psychomimetic and other side effects. There exists a need to improve on this therapeutic ratio. Potential methods include the use of more selective NMDA antagonists that modulate binding sites within the NMDA complex, using novel routes including central axis delivery, or in combination with drugs. Combinations of opioids and NMDA antagonists may hold the most promise. Recently, a 1:1 mixture of morphine with dexmethorphan hydrobromide allowed satisfactory pain relief in chronic pain patients at a significantly lower morphine dose.¹ In this study, there were 3 patients who had morphine as part of their conventional treatment. Although specific data is not available, it would be interesting to know if memantine proved to be more effective in these patients.     

A comparison of superficial versus combined (superficial and deep) cervical plexus block for carotid endarterectomy: a prospective, randomized study. (University of Michigan Medical Center, Ann Arbor, MI) Anesth Analg 2000;91:781–786.

Carotid endarterectomy may be preformed by using cervical plexus blockade with local anesthetic supplementation by the surgeon during surgery. Most practitioners use either a superficial cervical plexus block or a combined (superficial and deep) block, but it is unclear which offers the best operative conditions or greatest patient satisfaction. This study compared the 2 techniques in 40 patients undergoing carotid endarterectomy. The patient randomly received either a superficial or a combined cervical plexus block. Bupivacaine 0.375% to a total dose of 1.4 mg/kg was used. The main outcome measure was the amount of supplemental lidocaine 1% used by the surgeon. Subsidiary outcome measures were postoperative pain score, sedative and analgesic requirements before and during surgery, and postoperative analgesic requirements. Median supplemental lidocaine requirements were 100 mg in the superficial block group and 115 mg in the combined block group. These differences were not statistically significant. There was no significant difference in the number of patients needing postoperative analgesia between the groups in the 24 h after surgery. The median time to first analgesia in the superficial block group was 150 min. more than in the combined block group, but this difference, although large, was not statistically significant. No significant differences were found between the anesthetic techniques studied. Comment by Alan Kaye, M.D. Carotid endarterectomy surgery can be performed with regional or general anesthesia. It is probable that a substantial majority of CEAs performed in North America are performed under general anesthesia. Debate over choice of regional versus general anesthesia persists because of various studies of risks and benefits. Each type of anesthesia has its own advantages and disadvantages, which must be considered when choosing the optimal anesthetic for patients. Regional anesthetic techniques available include local infiltration, superficial and deep cervical plexus block, a combination of these with or without contralateral superficial plexus, and cervical epidural anesthesia. This prospective, randomized, double‐blinded study compared superficial versus combined (superficial and deep) cervical plexus block in 40 patients. Outcomes were measured by supplemental local anesthetic used by the surgeon, postoperative pain scores, and sedative and analgesic requirements before, during, and postoperatively. The results showed no significant difference in either study group. Therefore, this small study suggests that superficial block should be preferred in as much that it is relatively easy to do and the potential side‐effects are far less than deep cervical block. Larger studies are warranted in this difficult population of patients.     

Axillary brachial plexus block with patient controlled analgesia for complex regional pain syndrome type I: a case report. (National Cheng Kung University, Tainan, Taiwan) Reg Anesth Pain Med 2001;26:68–71.

A 32-year-old man who suffered from complex regional pain syndrome type I (CRPS I) of the right upper limb after surgical release of carpal tunnel syndrome of the right hand is the subject of this case report. Symptoms and signs over the right hand were alleviated under rehabilitation and conventional pharmacological management, but severe painful swelling of the right wrist persisted. Axillary brachial plexus block (BPB) with patient controlled analgesia (PCA) was performed on the 32^nd postoperative day, which soon resulted in significant reduction of pain with gradual improvement of function of the right wrist. Conclude that axillary BPB with PCA may provide patients with CRPS I of the upper limb a feasible and effective treatment.     

Morphine tolerance increases [3H]MK-801 binding affinity and constitutive neuronal nitric oxide synthase expression in rat spinal cord. (National Medical Defense Center, Taipei, Taiwan) Br J Anaesth 2000;85:587–591.

N‐Methyl‐D‐aspartate (NMDA) receptor antagonists and nitric oxide synthase (NOS) inhibitors inhibit morphine tolerance. In the present study, a lumbar subarachnoid polyethylene (PE10) catheter was implanted for drug administration to study alterations in NMDA receptor activity and NOS protein expression in a morphine‐tolerant rat spinal model. Antinociceptive tolerance induced by intrathecal morphine infusion (10 μg h^?1) for 5 days. Co‐administered MK801 with morphine was used to inhibit the development of morphine tolerance. Lumbar spinal cord segments were removed and prepared for [³H]MK‐801 binding assays and NOS western blotting. The binding affinity of [³H]MK‐801 was higher in spinal cords of morphine‐related rats than in control rats. There was no difference in B_max. Western blot analysis showed that constitutive expression of neuronal NOS protein in the morphine‐tolerant group was twice that in the control group. This up‐regulation was partially prevented by MK‐801. The results suggest that morphine tolerance affects NMDA receptor binding activity and increases nNOS expression in the rat spinal cord. Comment by Octavio Calvillo, M.D., Ph.D. Morphine tolerance may be due to receptor down‐regulation or receptor uncoupling; activation of the NMDA‐dependent pain‐facilitatory system may also play a role. It has been proposed that NMDA receptor activation may play a role in morphine tolerance. NMDA receptor antagonists and nitric oxide synthase [NOS] inhibitors may prevent morphine tolerance. Tolerance was induced in rats by intrathecal injection of morphine [10 ug/h] for 5 days, co‐administration of MK801 [NMDA antagonist] with morphine was used to prevent morphine tolerance. Lumbar spinal cord segments were removed and prepared for [H3]MK801 binding assays and NOS western blotting. The binding affinity of labeled MK801 was higher in spinal cords of morphine tolerant rats than in control rats. Western blot analysis showed that constitutive expression of neuronal NOS protein in the morphine tolerant rats was twice that in the control group, thus, up‐regulation was prevented by MK801. The results suggest that morphine tolerance affect NMDA receptor binding activity and increase neuronal protein expression in rat the spinal cord.