Stretching of the brachial plexus in rabbits

The brachial plexus of rabbits was stretched until mechanical failure. The level and site of rupture varied according to the direction of the stretching force. Upward and lateral traction of the forelimbs caused spinal nerve-root avulsions combined with nerve-trunk ruptures distal to the dorsal root ganglions. In such tractions the C5 nerves consistently exhibited postganglionic nerve-trunk rupture. The C6, C7, and C8 nerves had root avulsions. The T1 nerve was avulsed from the spinal cord in 7 cases out of 10; the other 3 cases had postganglionic nerve-trunk rupture. Downward traction of the forelimbs caused nerve avulsions from the scapulohumeral muscles innervated by the terminal branches of the brachial plexus and peripheral nerve ruptures in the course of the arm. The force producing trunk rupture of the C6 nerve was twice as great as that for root avulsion. The required stain was similar for nerve trunk rupture and root avulsion.     

Imaging the brachial plexus

Imaging the brachial plexus is challenging because of the complex anatomy of the region and the wide variety of pathology that can affect it. For the purpose of imaging, it is helpful to divide traumatic and nontraumatic entities affect-ing the brachial plexus. Improvements in imaging technology, including multidetector CT for CT myelography and the availability of full-field-strength MRI systems with fast gradients and dedicated surface coils for optimal spatial resolution, have led to more accurate prospective diagnoses and improved aid for neurosurgical planning for traumatic and nontraumatic brachial plexopathies. CT myelography is the current gold standard for the diagnosis of nerve root avulsions affecting the brachial plexus. MRI is the preferred modality for nontraumatic brachial plexopathy. Other modalities, such as US and PET, have a limited role in the evaluation of brachial plexus pathology. High-quality, high-resolution CT and MRI remain the mainstays for imaging the brachial plexus.     

Amyloidoma of the brachial plexus

BACKGROUND: Amyloidomas of the peripheral nervous system are rare lesions. Most commonly, they involve the gasserian ganglion and the branches of the fifth cranial nerve. No association with systemic amyloidosis has been reported. CASE DESCRIPTION: We describe an amyloidoma of the lower trunk of the right brachial plexus. At the age of 34 years, this 71-year-old female had undergone radical right mastectomy for breast cancer with axillary lymph node dissection followed by radiotherapy. On admission, she presented with burning pain to the right hand and mild motor deficit to the ulnar-innervated intrinsic hand muscles. A palpable lesion was found in the supraclavicular region. On surgical inspection, the lesion appeared to originate from the lower trunk of the right brachial plexus. The middle and upper trunks were dislocated. Histologically, fibrous connective tissue embedded small nerve bundles featuring perineurial and endoneurial fibrosis as well as amyloid. Amyloid featured immunoreactivity for both lambda and kappa chains. DISCUSSION: Localized amyloidoma of brachial plexus has never been reported. Because of compressive rather than infiltrative growth of the present lesion, a conservative surgery was achieved. Our immunohistochemical findings indicated that peripheral nerve amyloidomas are not, by definition, monoclonal in nature.     

Surgery of the brachial plexus

The principles and difficulties of surgery of brachial plexus lesions in 52 cases are reported. In 22 cases there was avulsion of one or more roots. Six lesions were infraclavicular. Reconstruction by means of autologous grafts was performed in 24 cases, neurolysis in 14 cases, direct suture in two cases, and intercostal neurotization in 12 avulsion cases. Fifty-one patients were evaluated on average 4 years after the operation. The result was good in 19 cases, fair in 13 cases and poor or nil in 19 cases. Regained function was best at the level of the elbow. Functional recovery of M. biceps after fascicular grafting was achieved in 16 cases. In neurotization cases, functional recovery was achieved in four cases.     

Surgery of the brachial plexus

The principles and difficulties of surgery of brachial plexus lesions in 52 cases are reported. In 22 cases there was avulsion of one or more roots. Six lesions were infraclavicular. Reconstruction by means of autologous grafts was performed in 24 cases, neurolysis in 14 cases, direct suture in two cases, and intercostal neurotization in 12 avulsion cases. Fifty-one patients were evaluated on average 4 years after the operation. The result was good in 19 cases, fair in 13 cases and poor or nil in 19 cases. Regained function was best at the level of the elbow. Functional recovery of M. biceps after fascicular grafting was achieved in 16 cases. In neurotization cases, functional recovery was achieved in four cases.     

Tumors of the brachial plexus

Over a 17-year period, 56 patients with 57 tumors involving the brachial plexus were operated upon. The 40 neural sheath tumors included 26 neurofibromas, 8 schwannomas, 4 malignant neural sheath tumors, 1 fibrosarcoma, and 1 meningioma. Nine of the neurofibromas were associated with von Recklinghausen's disease (VRD), and 2 others were what was termed regionalized neurofibromatosis characterized by involvement of one limb with extension along the course of one or more plexus elements. Seventeen tumors were not of neural sheath origin; 7 were benign and 10 were metastatic malignant tumors compressing or invading the plexus. Benign neurofibromas and malignant sheath tumors almost always presented with pain or functional neural deficit, whereas schwannomas often presented with a palpable mass as their only initial symptom. Patients with solitary neurofibromas were significantly older, often female, and more likely to have tumor on the right side than patients with schwannomas, malignant neural sheath tumors, or neurofibromas associated with VRD. Solitary neurofibromas could often be totally resected without added deficit by sacrificing fascicles entering and leaving tumor that were determined to be "nonfunctional" by intraoperative nerve action potential recordings. Resection of neurofibromas associated with VRD sometimes but not always resulted in significant loss. Operation is nonetheless recommended, especially when malignancy is suspected because of rapidly increasing size, when severe pain or neural deficit is present, or when compression of adjacent plexus elements is a concern. Schwannomas and benign non-neural sheath tumors can usually be extirpated without damage to plexus elements. Forequarter amputation is advised for malignant intrinsic tumors involving distal plexus elements even though gross total resection seems feasible.     

Schwannoma of brachial plexus

Brachial plexus tumours are a rare entity. Schwannomas are benign nerve sheath tumours and only about 5% arise from the brachial plexus. Due to its rarity and complex anatomical location they can pose a formidable challenge to surgeons. We present a case of a young patient who presented with an axillary swelling three months after a lymph node biopsy from the same axilla, which turned out to be a Schwannoma arising for the medial cord of the brachial plexus.     

Pain in avulsion of the brachial plexus

The author reviews the diagnosis and treatment of avulsion injuries of the brachial plexus. He discusses the nature of the pain and the use of transcutaneous nerve stimulation for its relief.     

Microsurgery in brachial plexus lesions

Twenty-two patients with brachial plexus lesions were reviewed 3-6 years after microsurgical repair. Four patients underwent nerve transfer between intercostal nerves and the musculocutaneous nerve. None of these achieved useful elbow flexion. Nerve grafting mainly in the upper part of the plexus was performed in six patients of whom five recovered a useful motor function in at least one important area. Twelve patients underwent neurolysis; useful motor function in at least one important area was achieved in eight. We conclude that microsurgical treatment of brachial plexus lesions is useful in lesions of the upper part of the plexus, distal to the dorsal root ganglion.     

臂丛神经的超声影像学研究

目的 采用高频超声观察国人不同位置臂丛神经的正常形态。方法 采用高频超声对11例健康志愿者行右侧臂丛神经检查，并用神经刺激针确认。在臂丛神经通路上缓慢移动超声探头或改变方向，以检查神经的连续性，获得最佳的臂丛神经纵面图和横断面图。所有臂丛神经声像图特征、解剖的变化、进针和神经定位均被记录。结果 11例健康志愿者臂丛神经均能清楚显示，在超声引导下行电刺激均被证实为神经组织。臂丛神经在横断面上表现为圆形或椭圆形的低回声结构，内部由点状回声组成，纵面上表现为线性较强回声结构。结论 高频超声能提供高质量的臂丛神经声像图。     

Microsurgical reconstruction of the brachial plexus

From 1975 till today we observed 170 injuries of the brachial plexus, mostly following motorcycle accidents (n = 146). Many of the injured were of young, age (15 to 25 years) and suffered from polytraumatism. 129 patients underwent microsurgical repair of the nerve lesion. Two years after surgery 96 had a follow-up: 27 very good, 33 satisfying and 28 bad = without functional success.     

Surgical exposure of the brachial plexus

A method of exposure of the brachial plexus is presented. Resection of the clavicle is emphasized in repairing large defects in the plexus to obtain primary anastomosis.