Vessels of the brachial plexus]

The blood supply of brachial plexus is described by means of lightened injected specimens of older human fetus. The following arteries have direct branches to brachial plexus: the aortic arch/brachiocephalica trunk, subclavia a., thyrocervical trunk, ascending cervical a., transverse cervical a., suprascapular a., and the acromial network. Secondary branches leave them that partly anastomose and also return from distal to proximal. The blood supply is luxurious.     

Dermatoglyphs and brachial plexus palsy

Perinatal brachial plexus palsy (PBPP) is a handicap quite commonly encountered in daily routine. Although birth trauma is considered to be the major cause of the defect, it has been observed that PBPP occurs only in some infants born under identical or nearly identical conditions. The aim of this study was to test the hypothesis of genetic predisposition for PBPP. It is well known that digito-palmar dermatoglyphs can be used to determine hereditary roots of some diseases. Thus, we found it meaningful to do a study analysis of digito-palmar dermatoglyphs in this disease as well, conducting it on 140 subjects (70 males and 70 females) diagnosed with PBPP. The control group was composed of fingerprints obtained from 400 adult and phenotypically healthy subjects (200 males and 200 females) from the Zagreb area. The results of multivariate and univariate analysis of variance have shown statistically significant differences between the groups observed. In spite of lower percentage of accurately classified female subjects by discriminant analysis, the results of quantitative analysis of digito-palmar dermatoglyphs appeared to suggest a genetic predisposition for the occurrence of PBPP.     

Computed tomography of the shoulders in patients with obstetric brachial plexus injuries: a retrospective study

Background

Scapular hypoplasia, elevation, and rotation (SHEAR) deformity and posterior subluxation of the humeral head are common tertiary sequelae of obstetric brachial plexus injuries (OBPI). Interpretations of images from bilateral computed tomography (CT) scans of the upper extremities are critical to the diagnosis and treatment plan for patients with these bony deformities resulting from OBPI.

Methods

We conducted a retrospective study to investigate the accuracy of radiologic reports in the diagnosis of SHEAR or posterior subluxation of the humeral head in OBPI patients. CT studies from 43 consecutive patients over a 33-month period were used in the study. For each patient, we compared the results from the radiologic report to those from a clinical examination given by the attending surgeon and to measurements taken from the CT studies by biomedical researchers.

Results

A comparison of SHEAR measured from the 3-D CT images to the diagnoses from the radiologists, revealed that only 40% of the radiological reports were accurate. However, there was a direct correlation between the use of the 3-D CT images and an accurate SHEAR diagnosis by the radiologists (p < 0.0001). When posterior subluxation was measured in the affected and contralateral shoulders, 93% of the patients that had greater than a 10% difference between the two shoulders did not have their deformity diagnosed. The radiological reports diagnosed 17% of these patients with a 'normal' shoulder. Only 5% of the reports were complete, accurately diagnosing SHEAR in addition to posterior subluxation.

Conclusion

Due to the low incidence rate of OBPI, many radiologists may be unfamiliar with the sequelae of these injuries. It is therefore critical that radiologists are made aware of the importance of an accurate measurement and diagnosis of the SHEAR deformity. Due to their lack of completeness, the radiological reports in this study did not significantly contribute to the clinical care of the patients. In order for OBPI patients to receive the highest standard of care, the final diagnosis from their radiological imaging should be deferred to a brachial plexus specialist who is experienced with these types of injuries.     

Technical note: the humeral canal approach to the brachial plexus

Many variations to the axillary approach to the brachial plexus have been described. However, the success rate varies depending on the approach used and on the definition of success. Recent work describes a new approach to regional anaesthesia of the upper limb at the humeral/brachial canal using selective stimulation of the major nerves. This report outlines initial experience with this block, describing the technique and results in 50 patients undergoing hand and forearm surgery. All patients were assessed for completeness of motor and sensory block. The overall success rate was 90 percent. Motor block was present in 80 percent of patients. Completion of the block was necessary in 5 patients. Two patients required general anaesthesia. The preponderance of ulnar deficiencies agrees with previously published data on this technique. No complications were described. Initial experience confirms the high success rate described using the Dupré technique. This technically straightforward approach with minimal complications can be recommended for regional anaesthesia of the upper limb.     

A giant plexiform schwannoma of the brachial plexus: case report

We report the case of a patient who noticed muscle weakness in his left arm 5 years earlier. On examination, a biloculate mass was observed in the left supraclavicular area, and Tinel's sign caused paresthesia in his left arm. Magnetic resonance imaging showed a continuous, multinodular, plexiform tumor from the left C5 to C7 nerve root along the course of the brachial plexus to the left brachia. Tumor excision was attempted. The median and musculocutaneous nerves were extremely enlarged by the tumor, which was approximately 40 cm in length, and showed no response to electric stimulation. We resected a part of the musculocutaneous nerve for biopsy and performed latissimus dorsi muscle transposition in order to repair elbow flexion. Morphologically, the tumor consisted of typical Antoni A areas, and immunohistochemistry revealed a Schwann cell origin of the tumor cells moreover, there was no sign of axon differentiation in the tumor. Therefore, the final diagnosis of plexiform Schwannoma was confirmed.     

Qualitative dermatoglyphic traits in brachial plexus palsy

It has been considered for many years that the cause of perinatal brachial plexus palsy (PBPP) is excessive lateral traction applied to the fetal head at delivery, in association with anterior shoulder dystocia, but this do not explain all cases of brachial plexus palsy. The incidence found in several family members could be suggestive for inheritance with variable expression. The aim of this study was to prove early found confirmations of genetic predisposition for PBPP In the previous studies, the quantitative dermatoglyphic analysis showed some differences in digito-palmar dermatoglyphs between patients with PBPP and healthy controls. Now this qualitative analysis will try to determine hereditary of those diseases. We analyzed digito-palmar dermatoglyphics from 140 subjects (70 males and 70 females) diagnosed with PBPP and 400 phenotypically healthy adults (200 males and 200 females) from Zagreb area as control group. The results of Chi-square test showed statistically significant differences for frequencies of patterns on fingers in females between the groups observed. Statistically significant differences were found on palms in III and IV interdigital areas in both males and females and in thenar and I interdigital area only in females. As it was found in previous researches on quantitative dermatoglyphic traits, more differences are found between females with PBPP and control group, than between males. The fact, that the main presumed cause of PBPP is obstetrical trauma, it could be associated with congenital variability in formation of brachial plexus.     

Clinical and neuropathological study about the neurotization of the suprascapular nerve in obstetric brachial plexus lesions

Background

The lack of recovery of active external rotation of the shoulder is an important problem in children suffering from brachial plexus lesions involving the suprascapular nerve. The accessory nerve neurotization to the suprascapular nerve is a standard procedure, performed to improve shoulder motion in patients with brachial plexus palsy.

Methods

We operated on 65 patients with obstetric brachial plexus palsy (OBPP), aged 5-35 months (average: 19 months). We assessed the recovery of passive and active external rotation with the arm in abduction and in adduction. We also looked at the influence of the restoration of the muscular balance between the internal and the external rotators on the development of a gleno-humeral joint dysplasia. Intraoperatively, suprascapular nerve samples were taken from 13 patients and were analyzed histologically.

Results

Most patients (71.5%) showed good recovery of the active external rotation in abduction (60°-90°). Better results were obtained for the external rotation with the arm in abduction compared to adduction, and for patients having only undergone the neurotization procedure compared to patients having had complete plexus reconstruction. The neurotization operation has a positive influence on the glenohumeral joint: 7 patients with clinical signs of dysplasia before the reconstructive operation did not show any sign of dysplasia in the postoperative follow-up.

Conclusion

The neurotization procedure helps to recover the active external rotation in the shoulder joint and has a good prevention influence on the dysplasia in our sample. The nerve quality measured using histopathology also seems to have a positive impact on the clinical results.     

Effects of anesthesia and nociceptive stimulation in an experimental model of brachial plexus avulsion

Unilateral dorsal rhizotomy of brachial plexus nerves (C5-Th1) performed under general anesthesia is known to induce self-mutilation in rats. The aim of this study was to determine the effect of different anesthetic agents, and of pre-rhizotomy nociceptive stimulation on the appearance of self-mutilation. Self-mutilation appeared in 78% of animals after rhizotomy had been performed under pentobarbital anesthesia. When ketamine was used as the general anesthetic, self-mutilation was almost suppressed (13%) and consisted of superficial erosions. Mechanical nociceptive stimulation, when applied just before the induction of ketamine anesthesia and subsequent rhizotomy, provoked self-mutilation in 91% of rats. Furthermore, a serious type of self-mutilation consisting of total amputation of the distal part of the forepaw was present in 28% of all self-mutilating animals after previous nociceptive stimulation. In terms of self-mutilation, these results suggest 1) the crucial role of anesthesia, especially that which involved NMDA receptors (ketamine), and 2) the need of an additional factor to chronic deafferentation, formed either by activity of nociceptive pathways just before rhizotomy (nociceptive stimulation preceding ketamine anesthesia) or by injury discharges (pentobarbital anesthesia).