The flexor pollicis brevis is a thenar muscle located within the hand and forms the medial aspect of the thenar eminence. It is described as having a superficial and deep part, the latter being variable in size. Anatomically, it originates from the tubercle of the trapezium and from the associated flexor retinaculum. It attaches to the base of the proximal phalanx of the thumb.
The flexor pollicis brevis performs a variety of movement functions, specifically flexing the metacarpophalangeal joint of the thumb. The muscle is innervated primarily by the median nerve via a recurrent branch, with the deep head being innervated by the deep branch of the ulnar nerve. The flexor pollicis brevis is provided with blood supply from the superficial palmar arch.
The flexor pollicis brevis is an important muscle of the thenar eminence and is critical to the movement of the thumb. Refer to Figure 1 for a palmar view of the thenar muscles.
The flexor pollicis brevis is a small but functionally important muscle of the hand. It is essential for the fine-grained movement of the thumb and is innervated by the median and ulnar nerves. It has an important attachment onto the proximal phalanx of the thumb, as well as origins from the tubercle of the trapezium and from the associated flexor retinaculum. It is supplied with blood from the superficial palmar arch.
The flexor pollicis brevis has two distinct parts – a superficial part and a deep part – with the latter being variable in size. It is responsible for flexing the metacarpophalangeal joint of the thumb when contracted. This contraction of the flexor pollicis brevis then allows for finer movements of the thumb such as fine-grained gripping and manipulating small objects.
The flexor pollicis brevis is also important for the overall stability of the hand and its ability to perform basic functional tasks. The innervation of the muscle allows for precise control of the thumb, and its attachments to the proximal phalanx of the thumb provide further stability. The deep head is innervated by the deep branch of the ulnar nerve, which also helps with the fine motor control of the thumb.
The flexor pollicis brevis is an important muscle of the thenar eminence and contributes to the overall movement of the thumb. Refer to Figure 1 for a palmar view of the thenar muscles, and remember that the flexor pollicis brevis is an important component of the thenar eminence and enables us to perform fine-grained movements with the thumb.
