Military Backpack Palsy & Heavy Rucking: Brachial Neuropathy

Backpack palsy, also clinically designated as rucksack palsy or rucksack-induced brachial plexopathy, is an acute or subacute compression and traction neuropathy of the brachial plexus caused by the shoulder straps of heavily loaded packs. While historically documented among military recruits, armed forces personnel, and tactical units undertaking long-distance marches with heavy rucksacks, this condition is increasingly encountered in civilian life among trekkers, school students, and urban commuters carrying overloaded backpacks. The physical mechanism combines intense downward gravitational compression of the clavicle onto the first rib with posterior traction on the shoulder girdle, producing focal conduction block or axonal injury across the upper, middle, or lower trunks of the brachial plexus.

Indian Armed Forces, Himalayan Trekkers, and School Bag Burdens

In India, heavy load carriage is widespread across multiple societal strata. Armed forces personnel, paramilitary forces (CRPF, BSF), and police cadets undergo rigorous field training carrying rucksacks weighing twenty-five to forty kilograms over rugged terrains. In civilian life, thousands of recreational enthusiasts undertake demanding Himalayan trekking expeditions in Uttarakhand, Himachal Pradesh, and Ladakh, often carrying poorly fitted, heavy backpacks without hip-belt offloading. Furthermore, millions of school children and competitive exam aspirants carry heavy school bags weighing eight to twelve kilograms on thin, unpadded shoulder straps, complaining of numb hands and shoulder aching by late afternoon.

Direct Clavicular Clamping, Ergotrophic Neural Traction, and Axonotmesis

The mechanical etiology of backpack palsy operates through two simultaneous vectors. First, the unpadded strap transmits direct downward compressive force across the middle third of the clavicle, pressing it against the superior surface of the first rib and clamping the costoclavicular tunnel. Second, the backward weight of the pack pulls the entire shoulder girdle into retraction and depression, stretching the brachial plexus trunks over the first rib like a bowstring. In mild cases, this induces temporary neurapraxia characterized by localized myelin displacement and conduction block. In severe cases involving heavy loads, partial axonotmesis occurs, resulting in motor weakness of the serratus anterior (long thoracic nerve), supraspinatus/infraspinatus (suprascapular nerve), or intrinsic hand muscles.

Load Offloading, Splinting, Scapular Rehabilitation, and Ergonomics

Management begins with immediate removal of the compressive load and temporary resting of the affected shoulder girdle. If significant motor weakness is present, a supportive arm sling is utilized for several days to prevent gravitational traction on the healing brachial plexus. Physiotherapy intervention focuses on gentle active-assisted range of motion, neurodynamic gliding, and progressive strengthening of the upper trapezius, levator scapulae, and serratus anterior to restore active shoulder suspension. Ergonomic education emphasizes the mandatory use of wide, padded shoulder straps, a rigid internal backpack frame, and a firm, well-adjusted hip belt that transfers eighty percent of pack weight to the pelvic girdle.

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