Brachial Plexus Injury: Symptoms, Types, Causes and Treatment

Brachial plexus injuries (BPIs) are among the most devastating nerve injuries, often resulting in significant disability, pain, and challenges to daily living. The brachial plexus—a complex network of nerves running from the spinal cord through the neck to the arm—controls movement and sensation in the shoulder, arm, and hand. When damaged, this vital network can disrupt life in profound ways. Understanding the symptoms, types, causes, and treatment options is crucial for individuals, families, and healthcare providers confronting BPI. This comprehensive guide synthesizes recent research to provide a clear, evidence-based overview of this challenging condition.

Symptoms of Brachial Plexus Injury

When the brachial plexus is injured, the symptoms can be sudden and severe or subtle and progressive, depending on the nature and extent of the damage. Early recognition of these symptoms is essential for timely medical intervention and maximizing the chances of a good recovery.

Symptom	Description	Impact	Source(s)
Weakness	Loss of strength in shoulder/arm/hand	Limits daily function	3 5 10
Paralysis	Complete loss of movement	Severe disability	5 6 8 13
Numbness	Loss of sensation, tingling	Risk of injury	1 2 3
Pain	Burning, neuropathic, or sharp	Reduces quality of life	3 4 14
Muscle Atrophy	Wasting of muscles	Loss of function	1 3 5
Autonomic Changes	Sweating, skin color or temperature changes	Indicates nerve involvement	2
Psychological Distress	Depression, anxiety, PTSD, suicidal ideation	Decreased well-being	4 14

Table 1: Key Symptoms

Weakness and Paralysis

• Weakness in the shoulder, arm, or hand is often the first sign of a brachial plexus injury. In more severe cases, paralysis—the complete inability to move part or all of the limb—may occur. The degree of weakness or paralysis depends on which part and how much of the plexus is injured. Injuries to the upper roots (C5-C6) typically affect shoulder and elbow movement, while lower root (C8-T1) injuries impact hand and wrist function 5 6 10 13.
• Motor deficits can range from mild (difficulty lifting objects) to profound (total limb immobility).

Sensory Changes

• Numbness, tingling, and loss of sensation are common, often manifesting as a "pins and needles" feeling or a complete lack of feeling in the affected area. Some patients report persistent "deadness" in the limb 1 2 3.
• This sensory loss increases the risk of unnoticed injuries (such as burns or cuts).

Pain

• Neuropathic pain is a hallmark of many BPIs, especially those involving severe trauma. Patients may experience burning, stabbing, or electric-shock-like pain. Studies show that up to 56% of patients with traumatic BPI develop neuropathic pain 3.
• Pain intensity is often unrelated to age but is strongly associated with the severity of nerve damage 3 14.

Muscle Atrophy

• Over time, muscles not receiving signals from the nerves will shrink (atrophy). This can further reduce functional ability and complicate rehabilitation 1 3 5.

Autonomic and Psychological Symptoms

• Some patients develop changes in sweating, skin color, or temperature—signs that the autonomic nerves are involved 2.
• The psychological toll is significant: rates of depression, PTSD, and even suicidal ideation are high among BPI patients, highlighting the need for comprehensive care 4 14.

Types of Brachial Plexus Injury

Brachial plexus injuries are categorized by their location, severity, and the nature of nerve damage. Understanding these types is key to diagnosis, prognosis, and treatment planning.

Type	Defining Feature	Common Causes	Source(s)
Upper Plexus	C5-C6 roots (Erb’s Palsy)	Traction, trauma	5 6 13 14
Lower Plexus	C8-T1 roots (Klumpke’s Palsy)	Stretching, car accidents	6 13
Complete Injury	C5-T1 involvement	Severe trauma	6 9 13 14
Preganglionic	Nerve root torn from spinal cord	Avulsion (motorcycle accidents)	8 13
Postganglionic	Injury distal to nerve root	Stretch, laceration	8 12 16
Closed	No open wound	Motorcycle/car crash	6 9 14
Open	Laceration or penetrating wound	Knife, gunshot	6 12
Obstetric	Injury during birth	Shoulder dystocia	5 11
Radiation-Induced	After cancer therapy	High-dose radiation	1
Tumor-Related	Plexus compressed by tumor	Neurofibroma, schwannoma	12

Table 2: Types of Brachial Plexus Injury

By Anatomical Location

• Upper Plexus Injuries (C5-C6, Erb's Palsy):

  • Affect shoulder and elbow; common in both adults (trauma) and newborns (difficult delivery).
  • Best prognosis for functional recovery 5 6 13 14.

• Lower Plexus Injuries (C8-T1, Klumpke’s Palsy):

  • Impact hand and wrist function; less common but often associated with severe trauma (e.g., car accidents).
  • Lower plexus palsy is more frequent in car accidents than motorcycle or bicycle accidents 13.

• Complete Brachial Plexus Injuries:

  • All roots (C5-T1) are affected; results in complete loss of function in the limb.
  • Seen in high-energy trauma, with the worst prognosis 6 9 13 14.

By Pathological Mechanism

• Preganglionic (Root Avulsion):

  • Nerve root is pulled out from the spinal cord.
  • Often seen in high-velocity motorcycle accidents; surgical repair is complex 8 13.

• Postganglionic:

  • Injury occurs distal to the nerve root (e.g., stretching, laceration).
  • May be more amenable to surgical repair 8 12 16.

By Injury Pattern

• Closed Injuries: Most BPIs, especially those from traffic accidents, are "closed"—no open wound is visible 6 9 14.
• Open Injuries: Caused by sharp objects (knives, glass) or penetrating trauma (gunshots) 6 12.

Special Types

• Obstetric Brachial Plexus Injuries: Occur during childbirth, often due to shoulder dystocia or forceps delivery 5 11.
• Radiation-Induced: Develop after cancer treatment, typically for head and neck tumors 1.
• Tumor-Related: Compression or invasion by nerve sheath tumors (neurofibromas, schwannomas) 12.

Causes of Brachial Plexus Injury

The causes of BPI are diverse, but high-energy trauma remains the leading factor in adults. Understanding these causes is critical for prevention, risk assessment, and tailored management.

Cause	Mechanism	At-Risk Population	Source(s)
Traffic Accidents	High-speed, violent trauma	Young adult males	6 9 13 14
Motorcycle Crash	Sudden traction/stretch	Motorcyclists	6 7 9 13 14
Car/Bicycle Crash	Direct impact/stretch	Vehicle occupants/cyclists	6 13 14
Sports Injuries	Falls/collisions	Athletes	7 13
Birth Trauma	Shoulder dystocia, forceps	Newborns	5 11
Penetrating Wound	Knife, glass, gunshot	Urban populations	6 12
Tumors	Nerve compression/invasion	Any age	12
Radiation	Post-cancer therapy	Cancer survivors	1
Whiplash	Stretching from sudden force	Car accident victims	2
Thoracic Outlet	Chronic compression	Adults, repetitive activities	12

Table 3: Causes of Brachial Plexus Injury

Traumatic Causes

• Motorcycle and Car Accidents:

  • The most common cause in adults, especially young men. Motorcycle accidents alone account for over 60% of cases in many studies 6 9 13 14.
  • High-energy collisions can cause traction, stretching, or avulsion of the nerve roots.

• Sports Injuries:

  • Contact and winter sports (e.g., skiing) can result in BPIs, though less frequently than vehicle accidents 7 13.

• Penetrating Trauma:

  • Stab wounds, glass cuts, and gunshot injuries can sever the plexus, leading to open injuries 6 12.

Non-Traumatic and Special Causes

• Obstetric Trauma:

  • During difficult deliveries, especially with shoulder dystocia or the use of forceps/vacuum extraction, excessive traction can injure the plexus in newborns 5 11.

• Tumors:

  • Benign or malignant tumors may compress the plexus, leading to progressive symptoms 12.

• Radiation Therapy:

  • High-dose radiation for head and neck cancers can cause delayed neuropathy involving the plexus 1.

• Thoracic Outlet Syndrome:

  • Chronic compression between the collarbone and first rib can injure the plexus over time 12.

• Whiplash:

  • Sudden acceleration-deceleration injuries, such as in car accidents, can stretch the plexus and produce symptoms 2.

Risk Factors

• Male Gender and Young Age: The majority of adult BPI patients are young men, reflecting the demographics of motor vehicle accidents 6 9 14.
• Concomitant Injuries: Fractures, brain injuries, and coma frequently accompany BPIs in severe trauma cases 7 9 14.
• Birth Weight and Delivery Complications: In newborns, high birth weight, gestational diabetes, and complicated deliveries increase risk 11.

Treatment of Brachial Plexus Injury

Treating BPI requires a nuanced, multidisciplinary approach, often combining surgery, physical therapy, and psychological support. Early intervention and accurate diagnosis are key to optimizing outcomes.

Treatment	Application/Indication	Aim/Outcome	Source(s)
Conservative	Mild injuries, early phase	Preserve ROM, reduce pain	8 15 17 18
Physical Therapy	All phases, pre/post-op, chronic	Restore function, prevent atrophy	18
Surgical Repair	No recovery by 3–6 months, severe	Restore nerve continuity	8 15 16 17
Nerve Grafting	Postganglionic rupture	Bridge nerve gap	8 16 19
Nerve Transfer	Root avulsion	Reinnervation	8 16 19
Muscle/Tendon Transfer	Severe, late-presenting cases	Restore lost movement	9 19
Free Muscle Transfer	Complete or long-standing injury	Restore function	9 19
Pain Management	Neuropathic pain	Improve quality of life	3 14 18
Psychological Support	All patients	Address mental health	4 14

Table 4: Treatment Approaches

Conservative Management

• Observation and Physical Therapy:
  • For mild injuries or those with potential for spontaneous recovery, initial treatment is conservative.
  • Physical therapy focuses on maintaining range of motion, muscle strength, and preventing joint stiffness 8 15 17 18.
  • Sensory re-education, kinesiotherapy, manual therapy, and electrotherapy are commonly used 18.

Surgical Interventions

• Timing is Critical:

  • Surgery is considered if there is no recovery or improvement within 3–6 months post-injury 8 15 16 17.
  • Early exploration is advised for open injuries, vascular compromise, or total/complete palsy 16.

• Nerve Grafting:

  • Used to bridge gaps in postganglionic injuries where the nerve ends are still present 8 16 19.
  • Best outcomes are seen when performed early and in younger patients.

• Nerve Transfer (Neurotization):

  • In cases of root avulsion where grafting is not possible, surgeons reroute a nearby functional nerve to reinnervate the paralyzed muscle 8 16 19.
  • Intercostal nerves or accessory nerves are common donors.

• Muscle/Tendon and Free Muscle Transfer:

  • For longstanding or complete BPIs, muscle or tendon transfers (e.g., gracilis muscle) can restore some function 9 19.

Pain and Psychological Management

• Pain Control:

  • Neuropathic pain is treated with medications (anticonvulsants, antidepressants), nerve blocks, and sometimes surgical procedures 3 14 18.
  • Persistent pain can significantly impact mood and function.

• Psychological Support:

  • High rates of depression, anxiety, and PTSD mandate integrated psychological care 4 14.
  • Regular screening and early intervention are crucial for holistic recovery.

Rehabilitation

• Long-Term Commitment:
  • Recovery is a prolonged process, often requiring years of therapy and adjustment 15 18.
  • Functional gains depend on injury type, timing of intervention, and adherence to rehabilitation protocols.

Conclusion

Brachial plexus injuries are complex, life-altering conditions requiring early recognition, accurate diagnosis, and a multidisciplinary approach to care. Despite their severity, advances in microsurgery and rehabilitation offer hope for improved outcomes.

Key Takeaways:

• Symptoms include weakness, paralysis, numbness, pain, muscle atrophy, and psychological distress.
• Types vary by location (upper, lower, complete), mechanism (preganglionic, postganglionic), and cause (traumatic, obstetric, radiation, tumor).
• Causes are dominated by high-energy trauma (motorcycle and car accidents), but also include birth injuries, tumors, and radiation.
• Treatment ranges from conservative management and physical therapy to advanced microsurgical repair, nerve transfers, and psychological support.

With a coordinated, patient-centered approach, individuals with brachial plexus injuries can achieve meaningful recovery and regain independence in daily life.