Dorsal scapular nerve injury after trigger point injection into the rhomboid major muscle: A case report.

BACKGROUND AND OBJECTIVE: We report the case of a patient who presented with right dorsal scapular neuropathy after a trigger point injection into the right rhomboid major muscle. Through a nerve conduction study and electromyography, we demonstrated dorsal scapular nerve injury in this patient. CASE REPORT: A 38-year-old man complained that his right shoulder functioned less optimally during push-up exercises after a trigger point injection 4 weeks prior. Physical examination revealed mildly reduced right shoulder retractor muscle strength compared with the left side. We performed a nerve conduction velocity test and electromyography 5 weeks after the injection. The compound muscle action potential of the right dorsal scapular nerve showed low amplitude (left vs. right side: 5.2 vs. 1.6 mV) and delayed latency (left vs. right side: 4.9 vs. 6.8 ms). Positive sharp wave (1+) and mildly reduced recruitment were seen on electromyography of the rhomboid major muscle. The findings of the nerve conduction velocity test and electromyography indicated partial right dorsal scapular neuropathy. The nerve injury seemed to have been caused by the needle inserted during trigger point injection. CONCLUSION: Clinicians should pay attention to the occurrence of dorsal scapular nerve injury when performing trigger point injection into the rhomboid muscle.

Anatomical structure and nerve branching pattern of the human infraspinatus muscle.

The function of the infraspinatus muscle, critical to rotator cuff function, is dependent upon the muscle's structure and innervation pattern. The morphology of the infraspinatus muscle has been inconsistently described in the literature. Additionally, the branching pattern of the suprascapular nerve in the infraspinous fossa has not been addressed in the literature. The purposes of this study were to determine: the arrangement of the infraspinatus muscle bellies; the branching patterns of the suprascapular nerve to the infraspinatus muscle; if the infraspinatus muscle was composed the neuromuscular compartments. Forty-eight infraspinatus muscles from 24 embalmed cadavers were studied using standard dissection techniques to determine morphological characteristics and innervation patterns. Results demonstrated that the infraspinatus muscles were comprised of three separate muscular partitions with each partition residing in a thin fascial compartment but all residing deep to the posterior scapular fascia. A first order suprascapular nerve branch was present in 91.6% of superior, 100% of middle, and 70.8% of inferior partitions. A first order nerve was present in all 3 muscular compartments of the same infraspinatus muscle in 62.5% of cases. Second order nerve branches were present in 8.3% of superior, 0% of middle, and 29.2% of inferior partitions. These findings help to determine a more complete and accurate understanding of the structure of the infraspinatus muscle. A better understanding of its structure could lead to a better understanding of the function of the muscle. Such information will enable more effective rehabilitation strategies for injuries involving the infraspinatus component of the rotator cuff.

The frozen shoulder syndrome. Description of a new technique and five case reports using the subscapular nerve block and subscapularis trigger point infiltration.

BACKGROUND AND OBJECTIVES: A frozen shoulder is considered by some authors to be a common stage of many disorders affecting the shoulder, while others regard it as an independent idiopatic condition. A consistent finding is that subscapularis muscle trigger points play a key role in the development of the frozen shoulder syndrome. Apart from the conventional treatment, a selective subscapularis fossa nerve block combined with subscapularis trigger points infiltration, may be an effective treatment in preventing chronic pain. METHODS: In this manuscript the posterior injection technique of the subscapularis fossa nerve block is described. RESULTS: Five patients with typical symptoms of frozen shoulder, who did not respond to conventional treatment, but obtained pain relief after a combination of a subscapularis nerve block with the infiltration of trigger points, are presented. CONCLUSION: The results of this block in various painful situations of the shoulder region suggest the importance of subscapularis muscle in the etiology of the frozen shoulder. Using this technique, we could demonstrate that a subscapular nerve block and subscapularis trigger points infiltration have both a diagnostic and therapeutic value for the treatment of the frozen shoulder.

Haloperidol reduces the sympathetic and thermogenic activation induced by orexin A.

This experiment tested the effect of haloperidol on the sympathetic and thermogenic effects induced by orexin A. The firing rates of the sympathetic nerves to interscapular brown adipose tissue (IBAT), along with IBAT and colonic temperatures and heart rate were monitored in urethane-anesthetized male Sprague-Dawley rats before and 5 h after an injection of orexin A (1.5 nmol) into the lateral cerebral ventricle. The same variables were monitored in rats with an intraperitoneal administration of haloperidol (1 mg/kg bw), a D(2) receptor antagonist. The results show that orexin A increases the sympathetic firing rate, IBAT and colonic temperatures and heart rate. This increase is reduced by the haloperidol. These findings suggest that dopaminergic system is activated during the orexin A-induced hyperthermia.

Damage of the long thoracic and dorsal scapular nerve after traumatic shoulder dislocation: case report and review of the literature.

A judo injury resulted in an anterior shoulder dislocation with a concomitant lesion of the long thoracic and the dorsal scapula nerve. This injury led to loss of function and extreme instability of the shoulder. Stabilization of the glenohumeral joint was successfully accomplished by surgery. The athlete declined further operative approaches to stabilize the scapula. The patient was able to return to the former level of athletic activity.