Partial BPI

About Partial BPI

Partial brachial plexus injuries usually involve C5-C6, often with C7, in upper-type patterns, or C8-T1 in lower-type patterns. Upper-type injuries weaken shoulder abduction and elbow flexion, while lower-type injuries impair finger and hand function. Both patterns benefit from prompt assessment, since acute partial BPI is more amenable to nerve reconstruction than complete injuries.

Evaluation begins with a focused history of the trauma, examination of every muscle group and grading of strength. Sensation is mapped across dermatomes, and provocative tests check for Tinel's sign along the plexus. MRI of the cervical spine and plexus, together with nerve conduction studies and EMG, distinguish stretch injury, rupture and root avulsion patterns.

Within the first year, the most reliable interventions are direct repair where ends can be approximated, sural nerve grafting across gaps, and selective nerve transfers. For upper-type injuries, spinal accessory to suprascapular and Oberlin-type ulnar fascicle to musculocutaneous transfers reliably restore shoulder abduction and elbow flexion. Distal targets are chosen to maximise donor-recipient matching.

For lower-type injuries, restoring intrinsic hand and long flexor function is challenging because of distance from injury to target muscle. Selective tendon transfers and free functioning muscle transfers may be combined with nerve work in chosen patients. Sensory transfers protect critical areas such as the thumb and index finger from inadvertent injury after surgery.

Postoperative care includes splinting in a protective position, early mobilisation of unaffected joints and structured physiotherapy. Smoking, uncontrolled diabetes and excess alcohol are addressed, as they impair nerve regeneration. Patients are reviewed every six to eight weeks during the first year, with reinnervation usually beginning between six and twelve months and continuing for up to two years.

Outcomes for partial injuries are generally encouraging, particularly in upper-type patterns operated within six months. We discuss realistic targets such as shoulder abduction range, elbow flexion strength and hand function honestly before surgery. Secondary procedures, including tendon transfers and joint fusions, may be planned later if specific deficits remain after the initial nerve work has matured.

What to expect

• Focused examination grading every muscle group and sensation
• MRI, nerve conduction studies and EMG to map the injury pattern
• Nerve repair or grafting where ends can be reconstructed
• Targeted nerve transfers for shoulder, elbow or hand functions
• Sensory transfers to protect critical hand zones
• Structured rehabilitation and periodic review

Recovery

• Splint or sling protection in the early postoperative weeks
• Active mobilisation of unaffected joints from day one
• First reinnervation signs commonly between six and twelve months
• Avoidance of smoking and tight glycaemic control to support nerve healing
• Long-term physiotherapy with periodic clinical review