Partial BPI

Understanding a Partial Brachial Plexus Injury

Partial Brachial Plexus Injuries are typically the result of accidents where the arm is forcefully stretched, pulled, or injured. These injuries often involve damage to the C5, C6 nerve roots, sometimes accompanied by injury to the C7 nerve root, in the neck. This results in weakness, numbness, or reduced mobility in the affected shoulder and elbow.

Impact of Partial Brachial Plexus Injuries

• Partial Brachial Plexus Injuries generally spare hand function. However, deficits can occur in shoulder stability, abduction (outward movement), external and internal rotation, elbow flexion (bending), and forearm supination (rotating the forearm outward). If the C7 nerve root is involved, there may also be a variable weakness in extending the elbow, wrist, and fingers, in addition to finger flexion. A less common variant of partial injuries, known as lower arm type injuries (C8, T1), presents with hand muscle weakness, finger extension deficits, and loss of sensation in the forearm and hand.
• Patients may notice a difference in the size of their pupils (meiosis), and the upper eyelid may droop (ptosis). This type of injury is often observed in men aged 15-25 years. Upper Brachial Plexus (C5, C6) injuries are more likely to stretch or rupture from their origin, while lower Brachial Plexus (C8, T1) injuries tend to avulse or detach from the spinal cord.

Immediate Actions for Suspected Partial Brachial Plexus Injuries

• In the immediate aftermath of an accident, it is vital to conduct a thorough examination to rule out fractures at the injury site or injuries to other body parts, such as the head, spinal cord, or chest. Assessing the patient’s level of consciousness and their ability to lift the limb after the accident, as well as any sensations experienced, can provide important clues for later management.
• Addressing any limb fractures takes priority before planning surgery for Brachial Plexus Injuries. After the patient has recovered from other injuries, a comprehensive examination of all joint movements in the paralyzed arm is performed. Hand function remains entirely normal in patients with partial Brachial Plexus Injuries involving C5, and C6 nerve roots. If the C7 nerve root is also affected, the patient may struggle to extend the elbow, wrist, and fingers, though finger flexion remains possible.
• For more details on the causes, investigations, and the role and timing of surgery in partial injuries, please refer to our Brachial Plexus Injuries page.

Surgery for Partial Brachial Plexus Injury

The timing of surgical intervention is crucial in cases of partial injuries, with the adage “sooner the treatment, better the outcome” holding true. Surgery aims to restore movement in the shoulder and elbow joints and involves exploring, repairing, and transferring nerves. In cases of sharp open injuries, immediate surgery is performed. Conversely, for blunt closed injuries, which are more common, observation is carried out for the initial 2-3 months, allowing for spontaneous recovery. If no recovery is observed after 3 months post-accident, nerve transfer surgery is conducted as early as possible.

Significance of Timing in Partial Brachial Plexus Injuries

For injuries occurring within 9 months to 1 year, surgery is still an option, although the chances of recovery are somewhat reduced compared to surgeries performed within 3 months. However, after 1 year post-accident, attempting nerve transfer surgery is observed to have significantly lower chances of success due to inadequate time for nerve regeneration. In such cases, specific targeted muscle and tendon transfers are preferred over nerve transfer surgery beyond 1 year post-accident.

Surgical Procedure of Nerve Repair/Transfer for Partial BPI

The optimal timing for this procedure is within a “golden” window of 3-5 months following the injury. This time frame ensures early and effective reactivation of paralyzed muscles, leading to muscle strength of grade 4.

The primary targets of surgery are restoring shoulder abduction and elbow flexion. The procedure is conducted under General Anesthesia, with patients admitted a day before surgery.

Routine blood investigations are performed, a pre-anesthetic check-up is conducted, and an informed written consent form is signed. In many cases, nerves are harvested from the leg to repair partial Brachial Plexus injuries. This procedure does not create any deficit in the leg, apart from mild sensory abnormalities in the outer aspect of the ankle region, which typically resolve over time.

a) Nerve Repair

Nerve repair is performed in cases of nerve rupture. The Brachial Plexus is explored to identify ruptured nerves, remove scarred nerve segments, and repair the nerves using grafts harvested from various parts of the body. Nerve repair is usually possible in upper Brachial Plexus ruptures. An incision is made in the neck region above the clavicle, muscles are dissected, and nerves are explored.

Neuromas are excised, and nerves are repaired using grafts from the leg if the proximal nerve roots are healthy. Additionally, the spinal accessory nerve is transferred to the supra-scapular nerve to restore the initiation of shoulder abduction movement, a critical transfer in all Brachial Plexus Injuries.

b) Nerve Transfer

Nerve transfer involves intentionally dividing a physiologically active nerve (with minimal donor-related complications) and transferring it to a more important yet irreparable paralytic nerve of the Brachial Plexus.

• Oberlin I & II Method: (For Elbow Movement)

The most commonly used nerve transfer technique for elbow flexion in upper arm-type BPI is the Oberlin transfer. The biceps muscle, responsible for elbow flexion, is supplied by the musculocutaneous nerve. An incision is made on the inside of the arm, and nerves are explored. One or two nerve fascicles are taken from the ulnar nerve and directly joined with the motor branch of the biceps muscle of the musculocutaneous nerve (MCN).

• Mackinnon’s Method: (For Shoulder Movement)

The preferred nerve transfer technique for shoulder abduction in upper arm-type BPI is the Susan Mackinnon method. The deltoid muscle, responsible for shoulder abduction, is supplied by the axillary nerve. An incision is made on the backside of the arm, and nerves are explored underneath the triceps and deltoid muscles. Nerve fascicles from the triceps nerve branch are taken and directly joined with the axillary nerve.

Recovery After Brachial Plexus Surgery

• The brachial plexus neurotization procedure is a long surgery and usually takes about 6 to 8 hours minimum.
• After the surgery, the patient is usually kept in the hospital for 2 days and is allowed to go home thereafter.
• The sutures are non-dissolvable and are removed after 14 days.
• After that, regular monthly follow-up examination is mandatory to assess the progress of the nerve repair and nerve regeneration.

Results After Surgery for Partial Brachial Plexus Injuries

The results of surgery for partial brachial plexus injuries are generally positive but remain somewhat unpredictable. Even in the best centers worldwide, success rates typically range from 70% to 80%.

The maximum result that a patient with full effort and physiotherapy gets incomplete brachial plexus injury is that he can-

• abduct (lift his arm away from the body) up to 90 degrees,
• flex the elbow (bend the elbow towards the body) and
• mild grip in hand (just to hold any object)
• mild to moderate sensory recovery in hand to prevent injury or burn.

So that he can use his paralyzed hand as a supportive hand.

Nerve regeneration occurs slowly at a rate of approximately 1 mm/day. Recovery from a brachial plexus injury takes time, and patients may not experience results for several months even after successful surgery.

The patient is advised for regular physiotherapy and TENS therapy (transcutaneous electric nerve stimulation) after the surgery.

A positive mindset and the support of family, friends, and healthcare professionals are important to recovery and rehabilitation.

Postoperative Care and Rehabilitation

Patients are advised to undergo regular physiotherapy and Transcutaneous Electric Nerve Stimulation (TENS) therapy following surgery. Maintaining a positive mindset and receiving support from family, friends, and healthcare professionals are crucial for recovery and rehabilitation. If functional recovery is not achievable despite all efforts after 1-1.5 years of surgery, the next stage of surgery is planned.

Addressing Incomplete Results After Surgery

The results of surgery for partial brachial plexus injuries can be somewhat unpredictable, with success rates of approximately 70% to 80% even in top-tier centers worldwide. In cases of ongoing muscle weakness or when specific arm functions need to be restored, patients may require additional surgeries in the future.

Management Beyond One Year After the Accident

If more than one year has passed since the accident, it is advisable to consider muscle or tendon transfers for Partial Brachial Plexus Injuries (C5678T1) . This approach helps optimize functional restoration when the window for nerve repair or transfer has closed.

• Partial Brachial Plexus Injuries (C5678T1)
• Less than 1 year of Injury- Complete Brachial Plexus injury (C56 or C567)
• More than 1 year of Injury – Complete Brachial Plexus injury (C56 or C567 )