Chapter 6 Wrist AXIAL 166 CORONAL 188 SAGITTAL 210 Wrist Axial 1 Normal Anatomy The extensor tendons to the wrist and hand are contained in six specific compartments. Pathologic Process Subluxation or dislocation of the extensor carpi radialis is diagnosed when the tendon is partially or completely dislodged from its groove in the dorsal aspect of the ulna. This is best evaluated on axial images. Diagnostic Consideration The wrist should be imaged in a neutral position midway between pronation and supination. In this position the extensor carpi ulnaris tendon lies in its groove on the distal ulna. The extensor carpi ulnaris tendon normally slides out of this position when the wrist is supinated, and the resulting configuration can be mistaken for a dislocation. Wrist Axial 1 Wrist Axial 2 Wrist Axial 2 Wrist Axial 3 Wrist Axial 3 Wrist Axial 4 Wrist Axial 4 Wrist Axial 5 Wrist Axial 5 Wrist Axial 6 Wrist Axial 6 Wrist Axial 7 Pathologic Process Tenosynovitis of the flexor digitorum tendons in the carpal tunnel is a common cause of carpal tunnel syndrome. A distal flexor tenosynovitis can rapidly ascend into the flexor compartment, affecting the median nerve in the carpal tunnel as well as other flexor tendons. Wrist Axial 7 Wrist Axial 8 Normal Anatomy The median nerve is higher in signal intensity and typically more oval in shape than the flexor tendons in the carpal tunnel. The size of the median nerve is maintained or slightly diminished as it progresses distally through the tunnel. Wrist Axial 8 Wrist Axial 9 Normal Anatomy Guyon’s canal is a potential space between the hook of the hamate and the pisiform. It transmits the ulnar artery and ulnar nerve. Pathologic Process In ulnar tunnel syndrome, the ulnar nerve becomes compressed within Guyon’s canal. Causes for this compression can include masses, repetitive trauma, or hook of hamate fracture. Wrist Axial 9 Wrist Axial 10 Normal Variant An os styloideum is an accessory ossification center that forms during embryonic development. It is located on the dorsum of the wrist at the base of the second and third metacarpals adjacent to the capitate and trapezoid bones. This may occasionally fuse with the second or third metacarpal or both. Arthrosis, irritation, and interference with movements of nearby extensor tendons sometimes occur. Ganglia, bursa, and tenosynovitis may deveop. Wrist Axial 10 Wrist Axial 11 Wrist Axial 11 Wrist Coronal 1 Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related posts: Forearm Upper Arm Plantar Plate Elbow Shoulder Knee Stay updated, free articles. Join our Telegram channel Join Tags: Netter Correlative Imaging Musculoskeletal Anatomy Jan 17, 2016 | Posted by admin in MUSCULOSKELETAL IMAGING | Comments Off on Wrist Full access? Get Clinical Tree
Chapter 6 Wrist AXIAL 166 CORONAL 188 SAGITTAL 210 Wrist Axial 1 Normal Anatomy The extensor tendons to the wrist and hand are contained in six specific compartments. Pathologic Process Subluxation or dislocation of the extensor carpi radialis is diagnosed when the tendon is partially or completely dislodged from its groove in the dorsal aspect of the ulna. This is best evaluated on axial images. Diagnostic Consideration The wrist should be imaged in a neutral position midway between pronation and supination. In this position the extensor carpi ulnaris tendon lies in its groove on the distal ulna. The extensor carpi ulnaris tendon normally slides out of this position when the wrist is supinated, and the resulting configuration can be mistaken for a dislocation. Wrist Axial 1 Wrist Axial 2 Wrist Axial 2 Wrist Axial 3 Wrist Axial 3 Wrist Axial 4 Wrist Axial 4 Wrist Axial 5 Wrist Axial 5 Wrist Axial 6 Wrist Axial 6 Wrist Axial 7 Pathologic Process Tenosynovitis of the flexor digitorum tendons in the carpal tunnel is a common cause of carpal tunnel syndrome. A distal flexor tenosynovitis can rapidly ascend into the flexor compartment, affecting the median nerve in the carpal tunnel as well as other flexor tendons. Wrist Axial 7 Wrist Axial 8 Normal Anatomy The median nerve is higher in signal intensity and typically more oval in shape than the flexor tendons in the carpal tunnel. The size of the median nerve is maintained or slightly diminished as it progresses distally through the tunnel. Wrist Axial 8 Wrist Axial 9 Normal Anatomy Guyon’s canal is a potential space between the hook of the hamate and the pisiform. It transmits the ulnar artery and ulnar nerve. Pathologic Process In ulnar tunnel syndrome, the ulnar nerve becomes compressed within Guyon’s canal. Causes for this compression can include masses, repetitive trauma, or hook of hamate fracture. Wrist Axial 9 Wrist Axial 10 Normal Variant An os styloideum is an accessory ossification center that forms during embryonic development. It is located on the dorsum of the wrist at the base of the second and third metacarpals adjacent to the capitate and trapezoid bones. This may occasionally fuse with the second or third metacarpal or both. Arthrosis, irritation, and interference with movements of nearby extensor tendons sometimes occur. Ganglia, bursa, and tenosynovitis may deveop. Wrist Axial 10 Wrist Axial 11 Wrist Axial 11 Wrist Coronal 1 Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related posts: Forearm Upper Arm Plantar Plate Elbow Shoulder Knee Stay updated, free articles. Join our Telegram channel Join Tags: Netter Correlative Imaging Musculoskeletal Anatomy Jan 17, 2016 | Posted by admin in MUSCULOSKELETAL IMAGING | Comments Off on Wrist Full access? Get Clinical Tree
