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

2. Bones Ulna Radius Articular disc Pisiform Triquetrum Lunate Scaphoid
Hamate
Capitate
Trapezoid
Trapezium

3. 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

4. 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

5. 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

6. 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

7. 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

8. References
Basran, S. (2015). Carpal Tunnel Syndrome: A Rare Manifestation of Distal Radius Osteoid Osteoma. Journal of Clinical Orthopaedics and Trauma, 6(3), Retrieved July 8, 2015.
Baylor Homepage for Brian A Garner. (1997, November 12). Retrieved July 10, 2015, from
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 ). 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