Subclavian Nerve Research Articles

Innervation of the human sternoclavicular joint.

The sternoclavicular joint (SCJ) functions as the basal joint of the entire upper limb and must move in the proper pattern for normal scapular motion. Afferent sensations from joints, such as proprioception and pain sensation, are important for maintaining the proper motion and condition of joints. Detailed anatomical data are useful for discussing injuries or surgeries that impair the afferent nerve to the SCJ. Nerve branches to SCJs were examined on 12 sides, and the subclavian nerve was investigated on six sides to clarify whether it innervates this joint. On seven of the 12 sides, the SCJ was innervated by two nerves, (1) a branch from the medial supraclavicular nerve that ran medially along the clavicle and (2) a branch from the lateral pectoral nerve that innervated the clavicular head and upper part of the sternocostal head of the pectoralis major. This branch ran medially behind the clavicular head of the pectoralis major and reached the SCJ. In the remaining five sides, the SCJ was innervated solely by the branch from the medial supraclavicular nerve. Subclavian nerves ended within the subclavius muscle or periosteum of the clavicle and were separate from the SCJs. Our data on the route of nerve branches to the SCJ suggest that injury or surgery, such as clavicle fracture or resection of the clavicular head of the pectoralis major for myocutaneous flap transfer, can impair the SCJ's afferent nerve supply.

Prevalence and anatomy of the anomalous subclavius posticus muscle and its clinical implications with emphasis in neurogenic thoracic outlet syndrome: Scoping review and meta-analysis

BackgroundThe subclavius muscle runs underneath the clavicle. However, there have been a few reports of a duplicated subclavius muscle which is commonly referred to as subclavius posticus muscle due to its orientation being posterior to the proper subclavius muscle. Its occurrence seems to potentially create a narrowing interval at the superior thoracic aperture as it crosses over the brachial plexus. It might also have functional influence on the shoulder girdle. PurposeTo provide comprehensive gross anatomy description of the variant “subclavius posticus muscle” and to investigate its reported clinical implications with emphasis on its involvement in causing brachial plexus compression. Basic proceduresA scoping review with meta-analysis of the gross anatomy of the subclavius posticus muscle was conducted along with investigating its correlation to the thoracic outlet syndrome. Forty-seven articles were pooled through two rounds of the selection process. The relevant information was extracted and meta-analyzed. Main findingsThe scoping review and meta-analysis of the 47 articles revealed a total prevalence of 11/2069 (4.9%); 10/1369 (5.1%) in cadaveric studies, and 1/700 (5.0%) in MRI studies. The subclavius posticus muscle is a short triangular muscle with an average length of 12 cm and an average width of 1 cm. It originates from the sternal end of the first rib in most cases with reported variants of one case originating from the costoclavicular ligament and one case where it was fused with the proper subclavius muscle. Its insertion is more variable: on the superior border of the scapula with variable length in 71.35%, on the coracoid process of the scapula in 25.42%, and on the clavicle in 0.90%. The subclavian nerve seems to be the dominant nerve supply with a 57.6% prevalence, while 25.8% are innervated by the suprascapular nerve. Other reported nerves were the nerve to the myolohyoid (4.5%), accessory phrenic nerve (4.5%), and a direct branch from the brachial plexus (2.0%). The blood supply was reported (only once) to be from the suprascapular artery. However, the venous drainage was not established at all. Principal conclusionsThe subclavius posticus muscle is a variant muscle occurring with a reported overall prevalence of 4.9%. It can compress the brachial plexus as it runs across at the space of the superior thoracic aperture with exquisite contact, and this can lead to a neurogenic thoracic outlet syndrome. It also can be involved in the vascular thoracic outlet syndrome. Lastly, it is important not to omit its potential influence in shoulder joint instability to some extent.

On the topography of n.phrenici and operations on it In tuberculosis patients

Interest in phrenicotomy, proposed by Sturz'eM in 1911 to treat lesions of the lower lobe of the lungs, was revived by Goetz. who proposed to combine radical phrenicotomy together with transection of the subclavian nerve, from which, in his opinion, the branches branch off to the diaphragm. Soon the question gave rise to a number of works, both anatomical, experimental and clinical, on the abdominal nerve, and the main attention of the authors was paid to determining the nature of the function of the nerve and its connection with the sympathetic nerve. At the 3rd All-Ukrainian Congress of Surgeons on the treatment of pulmonary tuberculosis with artificial diaphragm paralysis, many valuable considerations were expressed on the basis of large, comparatively clinical digital data (Mutti, Frayerman). The issue of phrenicotomy, as you can see, does not lose practical interest over time, which is why we decide to illuminate it from our point of view.

Innervation of the clavicle: a cadaveric investigation

BackgroundThis cadaveric study investigated the innervations of the clavicle and clavicular joints (ie, sternoclavicular and acromioclavicular joints).MethodsTwenty cadavers (40 clavicles) were dissected. A skin incision was made to permit exposure...

Brachial plexus injury after clavicle fracture operation: a case report and literature review

BackgroundOpen reduction and internal fixation (ORIF) is the preferred choice for treating clavicle fractures. The brachial plexus injury caused by ORIF of a clavicle fracture is very rare. If it is not treated in time, the function of the brachial plexus will be challenging to recover, which will eventually lead to upper limb dysfunction and seriously affect the patient’s quality of life. Our team recently used ORIF to treat a patient with a clavicle fracture, who developed brachial plexus injury symptoms after surgery.Case presentationA 34-year-old female patient was admitted to the hospital for 13 h due to the right shoulder movement restriction after a fall. Due to the significant displacement of the fracture, we used ORIF to treat the fracture. The surgery went well. When the anaesthesia effect subsided 12 h after the operation, the patient developed right brachial plexus injury symptoms, decreased right upper limb muscle strength, dysfunction, and hypoesthesia. Symptomatic treatments, such as nourishing nerve and electrical stimulation, were given immediately. Sixty days after the operation, the patient’s brachial plexus injury symptoms disappeared, and the function of the right upper limb returned to the preoperative state.ConclusionsPatients with clavicle fractures usually need to undergo a careful physical examination before surgery to determine whether symptoms of brachial plexus injury have occurred. Anaesthesia puncture requires ultrasound guidance to avoid direct damage to the brachial plexus. When the fracture end is sharp, reset should be careful to prevent nerve stump stabbed. When using an electric drill to drill holes, a depth limiter should be installed in advance to prevent the drill from damaging the subclavian nerve and blood vessels. When measuring the screw depth, the measuring instrument should be close to the bone surface and sink slowly to avoid intense hooks and damage to the brachial plexus. Try to avoid unipolar electrosurgical units to prevent heat conduction from damaging nerves, and bipolar electrocoagulation should be used instead. If symptoms of brachial plexus injury occur after surgery, initial symptomatic treatment is drugs and functional exercise, and if necessary, perform surgical exploration.

A meta-analysis on the anatomical variability of the brachial plexus: Part II — Branching of the supraclavicular part

IntroductionThe anatomy of the supraclavicular part of the brachial plexus is highly variable, therefore the aim of this study was to perform a systematic review and meta-analysis of the various origins of the long thoracic, dorsal scapular, suprascapular and subclavian nerves. Materials and methodsMajor electronic databases were searched to identify all cadaveric studies investigating the morphology of the supraclavicular part of the brachial plexus. Data on the origins of these nerves were extracted and classified. A random effects meta-analysis was performed to state the pooled prevalence estimates. ResultsA total of 26 studies, constituting a total of 1021 cases, were deemed eligible for inclusion into the meta-analysis. The usual origin of the long thoracic nerve from the C5, C6 and C7 roots was observed in 78.1% (95% CI 69.4–86.7%) of cases and 21.9% (95% CI 13.3–30.6%) had unusual origins. An accessory long thoracic nerve occurred in 0.3% (95% CI 0–0.7%) of cases. The overall prevalence of the dorsal scapular nerve arising from its usual origin the C5 root was found in 85.2% (95% CI 75.7–94.6%) of cases, while 14.8% (95% CI 5.4–24.3%) appeared abnormal. The suprascapular nerve emerged from its usual point on the superior trunk in 89.8% (95% CI 85.1–94.4%) of cases and in 10.2% (95% CI 5.6–14.9%) of cases had a variable origin. An accessory suprascapular nerve was present in 0.2% (95% CI 0–0.6%). Two possible sites of origin of the subclavian nerve were noted and the typical origin from the superior trunk was found in 98.3% (95% CI 96.3–100%) of cases and variable origin from the C5 root in 1.7% (95% CI 0–3.7%). All unusual origins of each nerve were much less common. ConclusionsThe nerves emerging from the supraclavicular part of the brachial plexus express a wide spectrum of potential origins. Based on their various origins, a new classification system for all the nerves belonging to the supraclavicular part was proposed. Knowledge of these variations and their prevalence data is important to prevent iatrogenic injuries and to state useful landmarks for interventions in the axilla.

English

The origin and distribution of the brachial plexus in wild boar ( Sus scrofa) , a mammal belonging to the Suidae family were studied. Twelve specimens of wild boar, which were fixed in 10% formalin solution through different points of subcutaneous, intravenous, intramuscular, and intracavitary injections, following by immersing the specimens in the same solution were used. In present study, the brachial plexus of wild boar was a set of nerve fibers formed by the ventral branches from the fifth (C5) to eighth (C8) cervical and the first (T1) thoracic spinal nerves. The subclavian nerve was originated from C5, while the suprascapular nerve had its origin from C5 to C7. The cranial and caudal subscapular nerves were predominantly originated from C6 and C7, as well was the axillary nerve. The origin of the cranial and caudal pectoral nerves was from C7-C8 and C8-T1, respectively. The musculocutaneous nerve was mostly originated from C6 and C7, while the median and radial nerves had origin from C7 to T1. The origin of the ulnar, thoracodorsal, and lateral thoracic nerves was mostly from C8 and T1, while the long thoracic nerve was predominantly originated from C7 and C8. All nerves were responsible for the innervation of scapular girdle structures, arm, forearm, thorax and abdomen. In conclusion, the origin and distribution of the brachial plexus nerves in wild boar ( Sus scrofa ) are similar to domestic swine rather than to other wild species described in the literature.

Origem e distribuição do plexo braquial de Saimiri sciureus

Os autores descreveram a origem e composição do plexo braquial de quatro Saimiri sciureus, pertencentes ao Centro Nacional de Primatas (Cenp), Ananindeua/PA, os quais foram fixados com formaldeído e dissecados. Os achados revelaram que o plexo braquial desta espécie é constituído por fibras neurais provenientes da união das raízes dorsais e ventrais das vértebras cervicais C4 a C8 e torácica T1, e organizado em quatro troncos. Cada tronco formou um nervo ou um grupo de nervos, cuja origem variou entre os animais; na maioria, foi encontrado o tronco cranial originando o nervo subclávio, o tronco médio-cranial dando origem aos nervos supraescapular, subescapular, parte do radial, e em alguns casos ao nervo axilar, nervo musculocutâneo e ao nervo mediano; o tronco médio-caudal formou parte do nervo radial, e em alguns casos os nervos axilar, nervo musculocutâneo, nervo mediano, nervo toracodorsal, nervo ulnar e nervo cutâneo medial do antebraço, sendo os dois últimos também originados no tronco caudal.

Analysis 25 cases of Stryke collar-bone hook nickelclad in treatment of acromioclavicular dislocation and distal collar bone fracture

Objective To investigate the therapeutic efficacy of Stryke collar-bone hook niekelclad in management of acromioolavicular dislocation and distal collar bone fracture.Methods 25 cases of collar-bone fracture with CRIF operation using collar-bone hook nickelclad were included.Patients were followed up for 6～27 months after operation.Results The patients'post-operative function were evaluated with Karlsson standard.23 of 25 cases were categorized as grade A and the other 2 were grade B.There was no complication associated with injury of subclavian nerve or vessel,no infection,no loose and prolapse of internal fixation devices 8,8 well as fracture disunion or malunion.X-ray shows the lesions of collar-bone fracture recovered well without acromioclavicular disloeation on X-ray image.All patients achieved painless free-running after 2～3 months.Conclusion The application of coliar.bone hook nickelclad could reduce the chance of prolapse in patients with acromiaclavicular dislocation and distal collar bone fracture.As the acromioclavicular facet was not involved or impaired.there is a great advantage in reduced complication such as traumatic arthritis compared to those who received Kirschner wire ect.This method is characterized by little wound,fixation firmly and early recovery of the joint,and is effective to cure distal collar bone fracture and acromioclavicular dislocation. Key words: Collar-bone hook nickelclad; Distal collar bone fracture; Acromioclavicular dislocation

Cervical Plexus Block Provides Postoperative Analgesia After Clavicle Surgery

To the Editor: We report a case of successful postoperative analgesia after clavicular open reduction and internal fixation (ORIF) using a cervical plexus block (CPB). While an interscalene block could provide analgesia, at the price of motor and sensory blockade of the upper extremity, using a CPB, to our knowledge, has not been described before. A healthy 49-year-old woman undergoing right clavicular ORIF was given preoperatively a deep (C2–C4) and superficial CPB according to the classic approach (1) using 0.5% bupivacaine. The surgical procedure was performed under general anesthesia. Following awakening from general anesthesia, the patient was pain-free until 14 hours postoperatively. She then took one dose of oral analgesics before discharge. The innervation of the clavicle and the overlying skin varies depending on the source in the literature between C3 and C6. Figure 1 summarizes the dermatome distributions published by several authors. The clavicle itself has been reported to be innervated either by C4, or by C5 and C6 (subclavian nerve).Figure 1.: Dermatome distributions determined by different methods: A, Foerster’s map, constructed using stimulation of nerve stumps and observing for vasodilatation (2). B, Head’s diagram, from observation of patients with herpes zoster lesions (3). C, Bonica’s map, developed “on the basis of personal observation and data published by others” (4). D, Keegan’s chart, established on the pattern of hypoalgesia following loss of a single nerve root (5).This case demonstrates that a cervical plexus block can provide analgesia after clavicle ORIF. It remains to be determined whether a CPB could be used as a sole anesthetic for clavicle ORIF in selected patients. Daniel S. Choi, MD, MBA Arthur Atchabahian, MD Anthony R. Brown, MD Department of Anesthesiology; Columbia University College of Physicians and Surgeons; New York, NY; [email protected]

Catecholamine-induced changes in vascular capacitance and sympathetic nerve activity in dogs.

The effects of three catecholamines, dopamine, epinephrine, and dobutamine, on the systemic circulation, especially on systemic vascular capacitance, were studied using cardiopulmonary bypass in dogs anesthetized with pentobarbital. Venous outflow was divided into three compartments: splanchnic, renal, and other; changes in systemic blood volume (SBV) were calculated from the changes in total venous outflow. To examine the contribution of sympathetic discharge to these vascular responses, sympathetic efferent nerve activity (SENA) from the ventral ansa subclavian nerve was recorded simultaneously. Experiments were done under three conditions: control, after baroreceptor deafferentation, and after hexamethonium injection with low and high doses of each catecholamine. During control and after baroreceptor deafferentation, dopamine- and epinephrine-induced changes in SBV were less than those after hexamethonium, and not significant except with low dose epinephrine. After hexamethonium, dopamine (200 micrograms/kg), epinephrine (10 micrograms/kg), and dobutamine (100 micrograms/kg) reduced SBV by 10.6 +/- 3.4, 13.1 +/- 1.7, and 1.9 +/- 0.3 mL/kg, respectively. Splanchnic outflow increased significantly with dopamine and epinephrine after hexamethonium. High dose dopamine and epinephrine significantly suppressed SENA to 38 +/- 9 and 15 +/- 6% of baseline, respectively. Low dose dopamine decreased arterial pressure and SENA. This suppression in SENA was attenuated but still observed after baroreceptor deafferentation. Dobutamine reduced SBV, but had no effect on SENA. These results suggest that dopamine and epinephrine primarily decrease SBV by venoconstriction in the splanchnic region, however, these effects are greatly modified by basal sympathetic discharge and changes in SENA and vascular tone.

Nonrecurrent and recurrent inferior laryngeal nerve: A surgical pitfall in cervical exploration

The exposure and preservation of the recurrent inferior laryngeal nerve is advocated by most experienced thyroid surgeons as the standard of care and as an essential component of routine dissection in cervical exploration. Anatomic variations in the position of this vital structure may present pitfalls during thyroidectomy. The nonrecurrent inferior laryngeal nerve: The possibility of a nonrecurrent inferior laryngeal nerve is a known but rare (0.6%) anatomic variant. A nonrecurrent nerve may come directly from the vagus nerve high in the neck and run in a straight course toward the cricothyroid membrane in contrast to the normal retrograde entry into the larynx from the thoracic vagus. This abnormality was first described in autopsy cases [I], and, later, encountered in a surgical case report [ 21 and in a short series [ 31. An explanation has been sought for this abnormal course of the inferior laryngeal nerve by its association with embryologic vascular abnormality. In the embryologic origin of the aortic arches, an atypical development may result in an aberrant right subclavian nerve with the origin of the aorta left of the midline following a retroesophageal course. Nonrecurrence of the inferior laryngeal nerve on the left side: The embryologic explanation is most compatible with the nonrecurrent inferior laryngeal nerve described on the right side. There are very rare excep tions, reported in an autopsy case [4] and in two clinical cases [5], of a left-sided nonrecurrent inferior laryngeal nerve associated with a right-sided aorta and a left retroesophageal subclavian artery. The complex of these anatomic abnormalities was confirmed in two similar cases [Jl. Ipsilateral recurrent and nonrecurrent nerve:

Modifications by Halothane of Responses to Acute Hypoxia in Systemic Vascular Capacitance, Resistance, and Sympathetic Nerve Activity in Dogs

To examine the effects of halothane on segmental vascular responses to hypoxia, we used cardiopulmonary bypass with venous outflow divided into three compartments (splanchnic, coronary, and "other") in dogs anesthetized with pentobarbital sodium. The reservoir volume changes represented the inverted changes in systemic blood volume (SBV). In addition, sympathetic efferent nerve activity (SENA) was simultaneously recorded from the ventral ansa subclavian nerve. Experiments were done in two groups: severe hypoxia (PO2 of 19 mm Hg) and moderate hypoxia (PO2 of 50 mm Hg). Hypoxia provoked a significant decrease in SBV of 22.3 +/- 3.1 mL/kg and 10.5 +/- 1.6 mL/kg during severe and moderate hypoxia, respectively. Two percent end-tidal halothane attenuated the decrease in SBV to 10.3 +/- 1.3 mL/kg during severe hypoxia, and 1% halothane attenuated the decrease to 3.7 +/- 1.4 mL/kg during moderate hypoxia. Subsequent chemoreceptor denervation in the presence of 1% halothane completely abolished the moderate hypoxia-induced decrease in SBV. In the presence of halothane, vascular resistance during hypoxia was significantly less than that during control conditions. Sympathetic efferent nerve activity increased significantly during severe and moderate hypoxia by about 180% and 55%, respectively. During severe hypoxia, halothane did not cause any change in the response of SENA, whereas during moderate hypoxia, halothane tended to decrease SENA, but not significantly, and subsequent chemoreceptor denervation completely abolished the increase in SENA. Coronary resistance showed a hypoxia-induced reduction that was not influenced by halothane. These results suggest that acute hypoxia causes a decrease in SBV dependent on the severity of hypoxia.(ABSTRACT TRUNCATED AT 250 WORDS)