Dan Meyer, Ross Mungeam, Jaci Reidy Wrist Biomechanics Dan Meyer, Ross Mungeam, Jaci Reidy

Bones Ulna Radius Articular disc Pisiform Triquetrum Lunate Scaphoid Hamate Capitate Trapezoid Trapezium http://www.netterimages.com/images/vpv/000/000/009/9207-0550x0475.jpg http://www.cambridgequestions.co.uk/diagrams/Carpal%20tunnel.png

Joints Radiocarpal Triangular Fibrocartilage Complex Distal Radio-Ulnar Type: - Pivot Synovial Articulation: - Radius rotates about a relatively fixed distal end of ulna Movements: - Pronation - Supination Triangular Fibrocartilage Complex Articular Disc of radio-ulnar joint Purpose: - Separates joint cavities - Binds ulna and radius Borders: - Base: medial edge of ulnar notch of radius - Apex: lateral side of base of styloid process of ulna - Proximal surface: distal aspect of head of ulna Radiocarpal Type: - Condyloid synovial Articulation: - Distal end of radius and Articular disc - Proximal row of carpal bones (except pisiform) Movements: - Flexion/Extension - Adduction/Abduction - Circumduction

Muscles Flexors Extensors Abductors (radial deviation) flexor carpi radialis flexor carpi ulnaris adductor palmaris longus flexor digitorum superficialis Extensors extensor carpi radialis longus abductor extensor carpi radialis brevis extensor carpi ulnaris extensor digitorum Abductors (radial deviation) extensor pollicis longus extensor pollicis brevis abductor pollicis longus https://noexcuseshealth.files.wordpress.com/2013/03/forearm-muscles.jpg

Ligaments Palmar Side:Palmar Ulnocarpal Ligament Palmar Radiolunate Ligament Short Radiolunate Ligament Radioscaphocapitate Ligament Long Radiolunate Ligament Transverse Carpal Ligament (Flexor Retinaculum) Dorsal Side: Dorsal Radiocarpal Ligament Dorsal Radio-ulnar Ligament Dorsal Radial Metaphyseal Arcuate Ligament Other: Ulnar Collateral Ligament Radial Collateral Ligament

Wrist Axes and ROM Movement Axis Degrees of Motion Flexion Motion in Sagittal plane about Frontal axis of Radiocarpal Joint Norm: 70°-90°; Func: 10°-15° Extension Norm: 70°-80°; Func: ~35° Abduction (Radial Deviation) Motion in Frontal Plane about Sagittal Axis through Lunate/Capitate Norm: 20°- 25° Adduction (Ulnar Deviation) Norm: 30°- 40° Supination Motion in Transverse Plane about near Longitudinal Axis through radial head to ulnar head Norm: 80°- 90°; Func: 50° Pronation

Carpal Tunnel Syndrome Caused by repetitive tasks with fixed position of the hand Most often caused by compression of the median nerve One of the top reasons for missed workdays in USA http://johnrossmckay.com/wp-content/uploads/2014/07/Carpal-Tunnel.jpeg

References Basran, S. (2015). Carpal Tunnel Syndrome: A Rare Manifestation of Distal Radius Osteoid Osteoma. Journal of Clinical Orthopaedics and Trauma, 6(3), 190-194. Retrieved July 8, 2015. Baylor Homepage for Brian A Garner. (1997, November 12). Retrieved July 10, 2015, from http://web.ecs.baylor.edu/faculty/garner/ForearmAxes.htm Biel, A. (2010). Trail Guide to the Body (Fourth ed.). Books of Discovery Goodman, C., & Fuller, K. (2015). The Peripheral Nervous System. In Pathology: Implications for the physical therapist (4th ed., pp. 1668-1672). Philadelphia: Saunders. Hamill, J., & Knutzen, K. (2009). Biomechanical basis of human movement (3rd ed.). Philadelphia: Wolters Kluwer Health/Lippincott Williams and Wilkins. Moore, K., & Agur, A. (2015). Essential clinical anatomy (Fifth ed.). Philadelphia: Wolters Kluwer Health/Lippincott Williams and Wilkins Netter, F. (2014). Atlas of human anatomy (Sixth ed.). Saunders, an imprint of Elsevier Thompson, D. (2002, December 6). WRIST JOINT COMPLEX. Retrieved July 5, 2015, from http://moon.ouhsc.edu/dthompso/namics/wrist.htm#arthro