Watson-Jones Lecture, 1976. Some lesions of the brachial plexus

The radius is longer of the two bones that make up the human antebrachium or forearm. At the proximal end, the radius articulates with the capitulum of the humerus and the radial notch of the ulna to form the elbow joint. At the distal end, the radius articulates with the ulna via the ulnar notch, forming the distal radioulnar joint. Distally, the radius also attaches to the carpal wrist bones (scaphoid and lunate) to form the radiocarpal joint.
The radius has a nail-shaped head, and a short...

Nerve plexuses are networks of interlacing nerves that serve as communication hubs to distribute and organize nerve action across various body regions. The nerve plexuses are organized into the cervical plexus located in the neck region, brachial plexus in the shoulder area, lumbar plexus found in the lower back, sacral plexus situated in the pelvis, and coccygeal plexus located in the coccygeal region.
The Cervical Plexus
The cervical plexus, formed by the anterior rami of the first four...

The plexuses of the lower body include the lumbar, sacral, and coccygeal plexuses, which innervate the abdomen, pelvis, legs, and coccygeal region. These plexuses control the transmission of sensory information and coordinate motor functions of the lower body.
The Lumbar Plexus
The lumbar plexus is situated within the lumbar region of the back and is primarily formed by the first four lumbar spinal nerves (L1 to L4). This plexus extends its branches into several nerves, including the...

The subclavian artery transitions into the axillary artery as it exits the chest and enters the axillary region. This artery is critical for supplying blood to the shoulder area, including the head of the humerus, through the humeral circumflex arteries. As the vessel continues into the upper arm or brachium, it becomes the brachial artery. This artery plays a key role in vascularizing the brachial region and bifurcates at the elbow into several branches. These branches include the deep...

Spinal cord injury progresses through two interconnected phases: primary injury and secondary injury.Primary InjuryPrimary injury happens at the moment of trauma and involves immediate mechanical damage to the spinal cord.Compression happens when broken vertebrae, herniated discs, or accumulating blood (such as a hematoma) press directly against the spinal cord, distorting its normal shape and function. In cases of contusion, the cord is bruised by a blunt force (like penetrating injuries or...

Alterations in muscle tone are common manifestations of neurological disorders and reflect dysfunction within different nervous system regions. Spasticity, paratonia, and dystonia represent distinct forms of hypertonia, each with unique mechanisms, clinical features, and diagnostic importance.CharacteristicsSpasticity happens from upper motor neuron lesions and is characterized by velocity-dependent resistance to passive movement. Clinical features include:Exaggerated deep tendon reflexesClonus...