The pattern of colorectal dysfunction changes with time since spinal cord injury

BACKGROUND: Cross-sectional studies suggest that colorectal dysfunction after spinal cord injuries (SCI) worsens as time goes by. However, follow-up studies are needed to prove this. STUDY DESIGN: Prospective study. OBJECTIVE: To describe long-term colorectal function in SCI patients. SETTING: Members of the Danish Spinal Cord Injuries Association. METHODS: In 1996, 424 members of the Danish Paraplegic Association answered a detailed questionnaire describing their colorectal function. In 2006, those who continued as members (n=284) received an identical questionnaire. Data for patients responding both in 1996 and in 2006 (n=159) were compared. RESULTS: In 1996, 25% of the respondents reported that colorectal dysfunction had some or a major impact on their quality of life. At follow-up 10 years later, it was 38% (P<0.005). In 1996 11% defecated less than every second day and 16% spent more than 30 min at each defecation; in 2006, it was 19% (P<0.01) and 25% (P<0.00001), respectively. Digital anorectal stimulation or evacuation was performed at least once every week by 48% in 1996 and by 56% in 2006 (P<0.0001). Fecal incontinence was reported at least once a month by 22% in 1996 and by 17% in 2006 (P<0.001). CONCLUSION: While the frequency and severity of constipation-related symptoms increase with time since SCI, there is a decrease in the frequency of fecal incontinence.     

Pain,referred sensations,and involuntary muscle movements in brachial plexus injury

Finnerup NB, Norrbrink C, Fuglsang‐Frederiksen A, Terkelsen AJ, Hojlund AP, Jensen TS. Pain, referred sensations, and involuntary muscle movements in brachial plexus injury.
Acta Neurol Scand: 2010: 121: 320–327.
© 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objectives – Examination of the relationship between pain, sensory hypersensitivity, referred sensations and involuntary muscle jerks in patients with brachial plexus injury. Materials and methods – Fourteen patients with brachial plexus lesions were included. Spontaneous background and paroxysmal pain and mechanically and thermally evoked pain were recorded. Areas with sensory hypersensitivity and referred pain were mapped on a body chart. This was supplemented by electrophysiological analysis in three patients. Results – Sensory hypersensitivity and areas with pinprick‐induced referred phantom sensations were present in adjacent dermatomes. There was no clear relationship between chronic neuropathic pain and referred sensations, but there was a correlation between pain paroxysms and sensory hypersensitivity in dermatomes adjacent to deafferented areas. In three patients, simultaneous referred sensations and short latency motor action potentials ipsilateral to the denervated side suggested origin at subcortical sites. Conclusion – The study suggests a possible role of a spinal generator for sensory hypersensitivity and referred sensations following denervation.     

Placebo manipulations reduce hyperalgesia in neuropathic pain

Several studies have shown that placebo analgesia effects can be obtained in healthy volunteers, as well as patients suffering from acute postoperative pain and chronic pain conditions such as irritable bowel syndrome. However, it is unknown whether placebo analgesia effects can be elicited in chronic pain conditions with a known pathophysiology such as a nerve injury. Nineteen patients who had developed neuropathic pain after thoracotomy were exposed to a placebo manipulation in which they received either open or hidden administrations of lidocaine. Before the treatment, the patients rated their levels of spontaneous pain and expected pain and completed a questionnaire on their emotional feelings (Positive Affect Negative Affect Schedule) and went through quantitative sensory testing of evoked pain (brush and cold allodynia, heat pain tolerance, area of pinprick hyperalgesia, wind-up-like pain after pinprick stimulation). The placebo manipulation significantly reduced the area of pinprick hyperalgesia (P=.027), and this placebo effect was significantly related to low levels of negative affect (P=.008; R(2)=0.362) but not to positive affect or expected pain levels. No placebo effect was observed in relation to spontaneous pain or evoked pain, which is most likely due to low pain levels resulting in floor effects. This is the first study to demonstrate a placebo effect in neuropathic pain. The possible mechanisms underlying the placebo effects in hyperalgesia are discussed, and implications for treatment are outlined.     

Cardiac imaging using gated magnetic resonance

To overcome the limitations of magnetic resonance (MR) cardiac imaging using nongated data acquisition, three methods for acquiring a gating signal, which could be applied in the presence of a magnetic field, were tested: an air-filled plethysmograph, a laser-Doppler capillary perfusion flowmeter, and an electrocardiographic gating device. The gating signal was used for timing of MR imaging sequences (IS). Application of each gating method yielded significant improvements in structural MR image resolution of the beating heart, although with both plethysmography and laser-Doppler velocimetry it was difficult to obtain cardiac images from the early portion of the cardiac cycle due to an intrinsic delay between the ECG R wave and peripheral detection of the gating signal. Variations in the temporal relationship between the R wave and plethysmographic and laser-Doppler signals produced inconsistencies in the timing of IS. Since the ECG signal is virtually free of these problems, the preferable gating technique is IS synchronization with an electrocardiogram. The gated images acquired with this method provide sharp definition of internal cardiac morphology and can be temporarily referenced to end diastole and end systole or intermediate points.