Pisiform bone

Ossification of the wrist can be divided into two components: • • distal Ossification of the carpal bones Ossification of the carpal bones occurs in a predictable sequence, starting with the capitate and ending with the pisiform. At birth, there is no calcification in the carpal bones. Although there is great individual variability, approximate ossification times are as follows 1: • • • • • • • • Excluding the pisiform, a handy way to remember the order of ossification is to start at the capitate then move in an anti-clockwise direction on the volar surface of the right carpus. Ossification centers of the distal radius and ulna • distal radius: 1 year • distal ulna: 5-6 years

Flexor carpi ulnaris muscle (Musculus flexor carpi ulnaris) Flexor carpi ulnaris is a fusiform muscle located in the anterior compartment of the Together with other muscles of the anterior forearm, flexor carpi ulnaris adduction of the hand at the wrist. This article will discuss the Key facts about the flexor carpi ulnaris muscle Origin Medial epicondyle of humerus, olecranon and posterior border of ulna Insertion Pisiform bone, hamate bone, base of metacarpal bone 5 Action Wrist joint: Wrist flexion, wrist adduction Innervation Ulnar nerve (C7-T1) Blood Supply Posterior ulnar recurrent artery, ulnar artery Synonyms: Musculus flexor ulnaris carpi Flexor carpi ulnaris originates with two heads which are linked by a tendinous arch. The heads are named according to the bones they attach to; • The smaller humeral head arises from the common flexor origin on the • The more extensive ulnar head originates from the olecranon and proximal part of the posterior border of As the muscle fibers pass towards the wrist joint, they converge on a long tendon in the distal part of the forearm. This tendon passes into the palmar surface of the hand to insert onto the Why not pause and see what you already know about the flexors of the forearm with our quiz! Synonyms: Musculus flexor ulnaris carpi The tendon of flexor carpi ulnaris can be seen and palpated beneath the Flexor carpi ulnaris lies superficial to flexor digitorum superficialis and medial to palmaris longus. As they pass into the...

Due to the many parts in this “pinkie” side of the wrist, determining the cause of ulnar wrist pain can be very difficult. Your hand doctor will examine your wrist to see where the pain is located and how the wrist moves. X-rays might be taken. Sometimes other studies such as a CT scan or MRI might be needed. Some causes of ulnar wrist pain include: • • Arthritis of the joint(s) between bones • Ulnar impaction syndrome (when the ulna is longer than the radius, which can cause it to “bump into” the smaller wrist bones (Figure 2) • Inflammation or irritation of the tendons that bend and extend the wrist • Triangular Fibrocartilage Complex Injury (TFCC) (when the connection between the ulna bone and other structures in the wrist is torn by an injury or frayed over time) • • Masses (tumors), most commonly The treatment of ulnar wrist pain depends on the diagnosis. It can include some combination of activity modification, splinting or casting, © 2015 American Society for Surgery of the Hand This content is written, edited and updated by hand surgeon members of the American Society for Surgery of the Hand.

• 1 Anatomical Structure • 1.1 Articulating Surfaces • 1.2 Joint Capsule • 1.3 Ligaments • 2 Movements • 3 Mobility and Stability • 4 Blood Supply • 5 Innervation • 6 Clinical Relevance: Injuries to the Wrist Joint • 6.1 Scaphoid Fracture • 6.2 Anterior Dislocation of the Lunate • 6.3 Colles’ Fracture The wrist joint (also known as the radiocarpal joint) is an articulation between the radius and the carpal bones of the hand. It is condyloid-type synovial joint which marks the area of transition between the forearm and the hand. In this article, we shall look at the anatomy of the wrist joint – its structure, neurovasculature and clinical correlations. Anatomical Structure Articulating Surfaces The wrist joint is formed by an articulation between: • Distal end of the radius and the articular disk. • Proximal row of the carpal bones (except the pisiform). Together, the carpal bones form a convex surface, which fits into the concave shape of the radius and articular disk. The ulna is prevented from articulating with the carpal bones by the presence of a fibrocartilaginous ligament, the articular disk. Instead, the ulna articulates with the radius just proximal to the wrist – at the By Fig 1 – Articular surfaces of the wrist joint. Joint Capsule The joint capsule of the wrist joint attaches to the radius, ulna and the proximal row of the carpal bones. It is lined internally by a synovial membrane, which produces synovial fluid to reduce friction between the articulating struct...

INTRODUCTION Pisiform ligament complex syndrome (PLCS) is peri-pisiform ulnar palmar wrist pain caused by injury or disease to the components of the pisiform ligament complex (PLC). The PLC consists of the pisiform bone, pisiform ligaments, and the flexor carpi ulnaris (FCU) tendon. Injury to the pisiform ligaments leads to varying degrees of pisotriquetral (PT) joint instability with subsequent arthrosis. Osteoarthrosis (OA) of the PT joint is a degenerative joint disease involving the articular surfaces of the pisiform and triquetrum. Primary OA of the PT joint is an uncommon disorder. Many arthritic disorders of this joint are post-traumatic in nature preceded by PT joint instability. Familiarity with the anatomy and biomechanics of the pisiform and PT joint ligaments is crucial for understanding its pathologic disorders. ANATOMY At birth, the pisiform is cartilaginous and later develops an ossification center. A secondary ossification center rarely forms, and its failure to fuse with the remaining bone results in an accessory ossicle named os pisiforme secundarium . In 1945, Michelson reported that ossification of the pisiform occurs at a mean age of 8 years and 9 months. By age 12, the bone is fully developed. Until such time, the pisiform normally has a fragmented appearance that could be mistaken for a fracture among children. The pisiform is the smallest of the eight carpal bones. It is ovoid-spherical ( The pisiform ( arrow ) is located in a plane palmar to the pr...