AAEM minimonograph #43: Neuromuscular problems in the performing arts

Over the past 10–15 years, there has been increasing interest in the health problems of performing artists. In this review, I will discuss the major playing-related disorders seen in instrumental musicians. Among the 672 instrumentalists evaluated, the major diagnoses identified included musculoskeletal disorders in 64%, peripheral nerve problems in 22.5%. and focal dystonia in 7%. Sixty percent of instrumentalists were female although males predominate in the group with focal dystonia. The average age of those evaluated was 32 years. Among musculoskeletal disorders overuse syndrome is the most common. Frequent peripheral nerve disorders include thoracic outlet syndrome, carpal tunnel syndrome, and ulnar neuropathy. A characteristic distribution of symptoms and signs is identified for each instrument group. Electrodiagnostic studies are an important part of the evaluation of these disorders. With carefully designed treatment, the majority of instrumental musicians can be returned to full and pain-free playing activities. The success rate is highest in some entrapment neuropathies but remains low in focal dystonia. © 1994 John Wiley & Sons, Inc.     

Preoperative infiltration of the surgical area enhances postoperative analgesia of a combined low–dose epidural bupivacaine and morphine regimen after upper abdominal surgery

In a randomized, blinded trial we assessed the value of adding preoperative infiltration of the surgical area with bupivacaine to a low dose epidural regimen for postoperative pain treatment. Forty–nine patients scheduled for major upper abdominal surgery during combined thoracic epidural (bupivacaine + morphine) and general anaesthesia were studied. Postoperative analgesia was epidural bupivacaine 10 mg hr^-1 + morphine 0.2 mg hr^-1 for 72 h. The patients randomly received preoperative infiltration of the surgical area with bupivacaine 0.25%, 40 ml (group I); or no infiltration (group II). Pain was evaluated at rest, during cough and during mobilization six and eight h after start of surgery, and at 8 a.m. and 4 p.m. on the following days until 72 h after start of surgery. The sensory level of analgesia was evaluated by pin prick. We found no difference between the two groups during rest and cough. However, during mobilization group I had lower pain scores compared to group II ( P < 0.05). There was a significant reduction in the need for supplemental intramuscular morphine in the treatment group compared to the control group ( P <0.05). Thus an enhanced analgesic effect was demonstrated by adding preoperative infiltration of the surgical area with local anaesthetic to a low dose epidural bupivacaine/morphine regimen after upper abdominal surgery.     

国产鼻喷鲑鱼降钙素治疗骨质疏松性疼痛的疗效观察

目的观察国产鼻喷鲑鱼降钙素治疗骨质疏松性疼痛的疗效。方法采用随机分组对照设计。选择骨质疏松患者53例,随机分为两组,治疗组(30例)给予鼻喷鲑鱼降钙素,20u/次,1次/天,8周为1个疗程,停药后继续观察3周。对照组(23例)口服钙尔奇D片,1片/次,1次/天,共8周;采用国际惯用分级标准对疼痛予以评估。结果治疗组患者的疼痛明显改善,其总有效率为95%;在停药后缓解疼痛的作用仍可维持4周以上,Ⅲ度骨质疏松患者的治疗效果较Ⅰ度和Ⅱ度患者的效果差;对照组症状未见明显改善。结论用国产鼻喷鲑鱼降钙素治疗骨质疏松性骨痛,可明显缓解患者的疼痛症状。     

Vulvodynia: evolution of classification and management

The aim of this article is to make the reader familiar with the history and current status of vulvodynia. The account is presented as a historical survey, from the seventies to the nineties. It explains how and why the term came to be defined, and how some sub-groups – in particular dysaesthetic vulvodynia and vulval vestibulitis – have been identified and described. Their management is discussed. The importance of distinguishing these conditions from those which are variants of normal is stressed.
It is noted that these sub-groups have much in common, so that a degree of convergence or overlap has come to be recognised. In parallel with this, ideas concerning aetiology and optimal management have been clarified and are explored.
Appreciation of the present state of affairs, and of how it has been arrived at, will help to improve management. It will also facilitate the collection of data, which in turn may lead to further research and understanding of vulvodynia.     

Single visit root canal treatment: incidence of postoperative pain using three different instrumentation techniques

A clinical study was carried out on nonvital maxillary central incisors to evaluate the incidence of postoperative pain following single-visit root canal treatment using three different instrumentation techniques. Ninety teeth from 78 patients whose ages ranged from 14 to 63 years were selected and divided into three groups. Each group (30 teeth) was prepared by a different coronal-to-apical technique using different instrument movement depending upon the technique employed: modified double-flared, crown-downpressureless and balanced force techniques. No difference was observed in the incidence of postoperative pain among the groups.     

Transfer of lumbosacral load to iliac bones and legs Part 1: Biomechanics of self-bracing of the sacroiliac joints and its significance for treatment and exercise

This study deals primarily with the stability of the base of the spine. The sacroiliac joints are vulnerable to shear loading on account of their predominantly flat surfaces. This raises the question of what mechanisms are brought into action to prevent dislocation of the sacroiliac joints when they are loaded by the weight of the upper part of the body and by trunk muscle forces. First a model is introduced to compare load transfer in joints with spherical and with flat joint surfaces. Next we consider a biomechanical model for the equilibrium of the sacrum under load, describing a self-bracing effect that protects the sacroiliac joints against shear according to ‘the sacroiliac joint compression theory’, which has been demonstrated in vitro. The model shows joint stability by the application of bending moments and the configuration of the pelvic arch. The model includes a large number of muscles (e.g. the gluteus maximus and piriformis muscles), ligaments (e.g. the sacrotuberous, sacrospinal, and dorsal and interosseous sacroiliac ligaments) as well as the coarse texture and the ridges and grooves of the joint surfaces.     

Lamotrigine in the treatment of painful diabetic neuropathy

An open trial was conducted to study the potential efficacy of lamotrigine, a novel antiepileptic agent that blocks voltage-sensitive sodium channels and inhibits the release of glutamate, in relieving the pain associated with diabetic neuropathy. Subsequent to a 1 week washout period from previous analgesics, lamotrigine was administered at a dose of 25 mg/day for 1 week. The dose was doubled on a weekly basis up to 400 mg/day over 6 weeks. The McGill pain questionnaire (MPQ), spontaneous pain and a series of mechanical and thermal stimuli-induced pain were measured with the use of 0–100 visual analogue scale (VAS), on seven office visits. Pain level was also recorded by each patient twice daily, 1 week before, during, and 2 weeks after the treatment period with the use of a 0–10 numerical pain scale (NPS). Quantitative mechanical (Von Frey filaments) and thermal testing (QTT), and routine blood tests were performed at the beginning and at the end of the study. Thirteen patients completed the study. Spontaneous pain measured by VAS and NPS gradually dropped from a baseline of 49 ± 8 and 6.8 ± 0.6, to 20 ± 8.6 ( p < 0.001) and 4.3 ± 0.9 ( p < 0.001), respectively, at the end of the treatment period. Similarly, cold allodynia dropped from 38 ± 9.2 to 16 ± 15.3 ( p = 0.01), and the MPQ score from 13.6 ± 0.8 to 11.0 ± 1.5 ( p < 0.01). In contrast, no significant changes were found in the QTT, mechanical pain thresholds and laboratory results. Two patients were withdrawn from the study because of adverse effects. A long-term follow up showed that most patients were still using lamotrigine 6 months after the end of the study. The results of the study suggest that lamotrigine is potentially effective and safe in treating painful diabetic neuropathy.     

Enrichment of Glutamate-like Immunoreactivity in Primary Afferent Terminals Throughout the Spinal Cord Dorsal Horn

Although several lines of evidence indicate that glutamate is a neurotransmitter in primary afferent terminals, controversies exist on the proportion and types of such terminals that release glutamate. In the present study quantitative analysis of immunogold labelling was used to assess the presence of glutamate-like immunoreactivity in primary afferent terminals in laminae I – V of the rat spinal cord dorsal horn. Anterograde transport of choleragenoid – horseradish peroxidase from a spinal ganglion and tetramethyl benzidine histochemistry were used to identify primary afferent terminals in laminae I and III – V. Presumed C-fibre terminals in lamina II were identified on morphological criteria (dense sinusoid axon terminals). Primary afferent terminals in all dorsal horn laminae displayed significantly higher levels of glutamate-like immunoreactivity than pleomorphic vesicle-containing profiles in laminae III – IV and large neuronal cell bodies in laminae III – V. The density of gold particles over primary afferent terminals also significantly exceeded the average density of gold particles over laminae II and III – IV. The highest densities of gold particles were present over dense sinusoid axon terminals in lamina II. These findings suggest that glutamate, alone or in combination with other neuroactive compounds, is involved in the transfer of all sensory modalities from primary afferent fibres to dorsal horn neurons.     

Muscular performance after a 3 month progressive physical exercise program and 9 month follow-up in subjects with low back pain. A controlled study

The purpose of this study was to assess, in subjects with low back pain, the changes and their permanence in muscular performance after a 3 month progressive physical exercise program. Ninety subjects with chronic low back pain participated in the study. The study design was controlled and it was carried out in three groups: intensive training, home exercise, and control group. Isometric and dynamic muscle strength of the trunk and lower limb were measured, at the beginning of the study and after the 3 months exercise program, and then during each of the follow-up sessions. The Oswestry Index and back pain intensity were also determined. Both exercise groups received benefit from the progressive exercise program. Their muscular performance improved and their back pain intensity decreased significantly. Among the home exercise group, the Oswestry Index also changed positively. The results demonstrate that the home exercise program could be as effective as the intensive training program in increasing muscle strength, as well as decreasing back pain and functional disability among low back pain patients with mild functional limitations.     

Isokinetic quadriceps training in patients with patellofemoral pain syndrome

The aims of the present investigation were (a) to evaluate the effect of eccentric quadriceps training in patients with unilateral patellofemoral pain and (b) to compare the effect of eccentric and concentric quadriceps training in patients with bilateral patellofemoral pain. Fifteen patients (9 male and 6 female, aged 17–36 years with a mean of 27.5 years) participated in this study. Nine patients had unilateral pain and trained their painful leg eccentrically, while six had bilateral pain and trained one leg eccentrically and the other concentrically. Quadriceps muscle training was performed on a Kin-Com dynamometer at 90°/s and 120°/s angular velocity twice a week for 8 weeks. Before and after the treatment period the thigh muscle torques were measured on the Kin-Com dynamometer at 60°/s, 90°/s, 120°/s and 180°/s for quadriceps and at 60°/s and 180°/s for hamstrings. Nine controls, matched for gender and age with the group with unilateral pain, were tested in the same way on the Kin-Com dynamometer. For functional evaluation a knee score was calculated before training, after 8 weeks of training and at a mean of 3.4 years after completion of the training. After 8 weeks of training and at follow-up times of 1 and 3.4 years the patients were also questioned regarding whether or not they felt improvement from the training programme. To determine the degree of knee pain during the training Borg's pain scale was used. The results showed that, compared with the controls, the patients had a significantly lower knee extensor torque in their painful leg at all velocities measured. The greatest difference was found during eccentric actions. However, in comparison with the controls there were no significant differences in eccent ic and concentric knee flexor torques. After training there was a significant increase particularly in eccentric but also in concentric torque of the knee extensor in the painful leg of the eccentrically trained group. Of the six patients in the bilateral training group there were five who increased their concentric knee extensor torque and three who increased their eccentric torque. There were no significant differences in concentric and eccentric knee flexor torques before and after training in either of the legs in both training groups. The hamstring/quadriceps ratio was significantly higher in the patients' painful leg before training. However, due to increased quadriceps strength the hamstring/quadriceps ratio dropped after training. Patients in both groups reported no pain or mild pain during the training sessions. The eccentrically trained group was significantly improved both after 8 weeks of treatment and at follow-up 3.4 years later as evaluated using the knee score. The bilaterally trained group was significantly improved 3.4 years after completion of the training programme as evaluated using the knee score.