Overview
Definition:
Brachial plexus exploration is a surgical procedure involving direct visualization and assessment of the brachial plexus network
It is typically performed when there is suspicion of significant neurological injury, such as traumatic lesions, or to address specific pathologies like tumors or entrapment syndromes affecting the upper limb function
The aim is to identify the extent and nature of the pathology to guide subsequent management, which may include nerve repair, grafting, or decompression.
Epidemiology:
Brachial plexus injuries are relatively uncommon, with an incidence varying based on the cause
Traumatic injuries are more frequent, often associated with high-energy accidents like motorcycle crashes (approximately 70% of cases), falls, or sports-related trauma
Birth-related brachial plexus palsies (Erb's palsy) are also significant, occurring in about 0.4 to 5.7 per 1000 live births
Etiologies of non-traumatic origin include iatrogenic causes (e.g., post-radiation, surgery) or spontaneous events like neuralgic amyotrophy.
Clinical Significance:
The brachial plexus is crucial for motor and sensory innervation of the entire upper limb
Injuries can lead to profound functional deficits, including weakness, paralysis, sensory loss, and chronic pain, significantly impacting a patient's quality of life and independence
Early and accurate diagnosis, coupled with appropriate surgical intervention when indicated, is vital for optimizing functional recovery
Understanding brachial plexus anatomy and potential pathologies is essential for surgeons dealing with upper extremity trauma, reconstructive procedures, and neurological disorders.
Indications For Exploration
Traumatic Injuries:
Open wounds involving the plexus
suspected significant nerve avulsion or transection
neurological deficits disproportionate to clinical findings
failure to recover with conservative management after known traction or stretch injuries (e.g., motorcycle accidents).
Non Traumatic Conditions:
Suspected brachial plexus tumors (schwannomas, neurofibromas)
entrapment syndromes not responding to conservative treatment (e.g., Thoracic Outlet Syndrome)
iatrogenic injuries post-surgery or radiation
inflammatory conditions like neuralgic amyotrophy with persistent or progressive deficits.
Diagnostic Uncertainty:
When imaging (MRI, CT myelography) is equivocal or does not fully delineate the extent of pathology and clinical suspicion remains high
to rule out intraparenchymal lesions within the plexus.
Therapeutic Goals:
To precisely locate the site and nature of injury/lesion
to perform nerve repair (primary or secondary)
to harvest and implant nerve grafts
to decompress entrapped nerves
to excise tumors or other space-occupying lesions affecting the plexus.
Diagnostic Approach
History Taking:
Detailed mechanism of injury (if traumatic) including direction and force
timeline of symptom onset and progression
nature of neurological deficits (weakness, numbness, pain)
previous surgeries or radiation to the shoulder/neck region
occupational or recreational activities
presence of systemic conditions (e.g., diabetes, inflammatory disorders).
Physical Examination:
Systematic neurological assessment of motor strength (MRC scale) and sensation (dermatomal distribution) in the entire upper limb
assessment of reflexes
evaluation for signs of thoracic outlet syndrome (e.g., Adson's, Roos tests)
palpation for masses or tenderness
assessment of vascular status
Specific nerve root involvement (C5-T1) must be meticulously documented.
Investigations:
Electromyography (EMG) and Nerve Conduction Studies (NCS) to assess nerve continuity, localization of injury, and degree of axonal loss/demyelination
Magnetic Resonance Imaging (MRI) with contrast to visualize nerve roots, trunks, divisions, cords, and branches, and to detect tumors or inflammation
CT myelography for detailed visualization of nerve root avulsions and dural sleeves
Ultrasound for superficial lesions and Dynamic assessment in TOS.
Differential Diagnosis:
Cervical radiculopathy
spinal cord lesions
peripheral nerve entrapments distal to the plexus
shoulder joint pathologies
vascular abnormalities
central nervous system lesions mimicking peripheral nerve deficits.
Surgical Procedure Exploration
Preoperative Preparation:
Informed consent detailing risks, benefits, and alternatives
appropriate anesthetic planning (general anesthesia often preferred, regional block may be used)
patient positioning (lateral decubitus or prone for supraclavicular approach, supine for infraclavicular)
sterile preparation and draping of the operative field (neck, shoulder, arm).
Surgical Approaches:
Supraclavicular approach (most common) for accessing upper trunks and roots
infraclavicular approach for lower trunks and divisions
axillary approach for terminal branches
Choice depends on suspected lesion location.
Intraoperative Findings:
Direct visualization of nerve fibers, identifying continuity, continuity deficits, neuromas, entrapments, tumors, or signs of inflammation/scarring
Assessment of nerve excitability with nerve stimulator can help identify functional nerve fibers.
Intraoperative Management:
Careful dissection to avoid further nerve injury
meticulous hemostasis
identification of specific nerve components (roots, trunks, cords, branches)
decision for repair, grafting, decompression, or excision based on findings
Neurolysis may be performed
Nerve grafting techniques using autograft (e.g., sural nerve) or allografts are employed for significant gaps.
Closure:
Layered closure of surgical incision with sutures
sterile dressing application
Postoperative imaging may be considered if significant intervention was performed.
Postoperative Care And Complications
Postoperative Care:
Pain management
wound care and monitoring for infection
immobilization of the limb as indicated (e.g., sling)
early initiation of physiotherapy to prevent stiffness and maintain joint mobility
regular neurological assessment to monitor for improvement or deterioration.
Early Complications:
Hematoma formation
infection
nerve injury (iatrogenic)
pneumothorax (with supraclavicular approach)
phrenic nerve palsy
recurrent laryngeal nerve injury
vascular injury (subclavian artery/vein).
Late Complications:
Chronic pain syndromes
neuroma formation
scar tissue entrapment
loss of function despite intervention
stiffness
complex regional pain syndrome (CRPS)
non-union or graft failure.
Prevention Strategies:
Precise surgical technique and anatomical knowledge
careful dissection
judicious use of electrocautery
appropriate patient positioning
use of magnification (loupes or microscope)
diligent hemostasis
adequate prophylaxis for infection
prompt recognition and management of complications.
Prognosis
Factors Affecting Prognosis:
Severity and type of injury (avulsion vs
rupture vs
stretch)
time from injury to repair
age of the patient
specific nerve components involved (e.g., preganglionic vs
postganglionic injuries)
patient's overall health and compliance with rehabilitation
presence of comorbidities.
Outcomes:
Prognosis is variable
Complete recovery is less common with severe injuries
Functional recovery often involves a combination of motor and sensory return, which can take months to years
Significant improvements in strength, sensation, and pain reduction are considered successful outcomes
In cases of irreversible nerve damage or extensive loss, functional substitution strategies might be explored.
Follow Up:
Regular clinical and electrophysiological follow-up is essential, typically every 3-6 months initially, then annually
Physiotherapy and occupational therapy are crucial components of long-term management
Patients should be educated about realistic expectations and the importance of ongoing rehabilitation.
Key Points
Exam Focus:
DNB/NEET SS exams will test detailed brachial plexus anatomy, common injury patterns in trauma (especially motorcycle accidents), diagnostic modalities (EMG/NCS, MRI), and surgical indications for exploration
Understanding the different surgical approaches (supraclavicular, infraclavicular) and their target structures is critical.
Clinical Pearls:
Always consider the possibility of brachial plexus injury in high-energy trauma to the shoulder/neck region
Thorough neurological examination and appropriate investigations are paramount
Early surgical intervention offers the best chance for functional recovery in suitable cases
Multidisciplinary approach involving surgeons, neurologists, and physiotherapists is key.
Common Mistakes:
Inadequate history taking regarding mechanism of injury
Overlooking subtle neurological deficits
Delayed referral for surgical consultation
Performing exploration without adequate preoperative imaging and electrophysiological assessment
Inappropriate surgical approach for the suspected lesion
Insufficient or delayed postoperative rehabilitation.