Elbow Anatomy and
Biomechanics
Mimi Renaudin, DPT
University of Mississippi Medical
Center
Objectives
• Describe the anatomy and joint articulations
at the elbow
• Discuss the static and dynamic constraints
acting at the elbow
• Identify the neurovascular contributions
within the elbow joint
Elbow Snap Shot
• Trochoginglymoid joint
– 2 Degrees of freedom
 Flexion/Extension and forearm rotation
• Humerus
• Radius
• Ulna
Anatomy Overview
Joint Articulations
Humeroradial
Proximal Radioulnar
Humeroulnar
Anterior Muscular Component
• 9 muscles cross the anterior aspect of the
joint
– Only 3 have primary action on the elbow
• Radioulnar joint - rotation
• Remaining 4 muscles arise from common
flexor tendon on medial epicondyle
Elbow Flexors
Radioulnar Motion
• Supinator, pronator
teres with
assistance from
pronator quadratus
distally
Anterior Musculature
• Final 4 muscles
attach on medial
epicondyle
• Primary actions
occur at the wrist
and digits
–
–
–
–
PL
FCR
FCU
FDS
Posterior Muscular Component
• Elbow extensors: triceps, anconeus
– Triceps: 3 heads
 Long: crosses GH and elbow
 Medial/Lateral: only cross elbow
– Anconeus
• Common extensor tendon
Elbow Extensors
Lateral Epicondyle Attachments
• Extensor carpi
radialis longus
• Extensor carpi
radialis brevis
• Extensor digitorum
• Extensor carpi
ulnaris
• Extensor digiti
minimi
Capsuloligamentous Complex
• Medial collateral ligament
• Lateral collateral ligament
Medial Collateral Ligament
• Resists valgus stress
• Limits extension
• Taut throughout arch of
motion
– Anterior fibers most taut
in extension
– Posterior bundle is taut
in flexion
• Transverse fibers
provide valgus stability
and help with joint
approximation
Vascular Contribution
Normal Elbow Motion
• Normal ROM:
– Elbow 0-145°
– Pronation: 80°
– Supination: 85°
 Functional ROM:
 Elbow 30-130°
 Pronation: 50°
 Supination: 50°
Carrying Angle
• Formed by valgus tilt of the axis of rotation
(humeral articulation) and the valgus
orientation of the ulnar shaft in reference to
the olecranon
References
1. DeLee, Drez. DeLee and Drez’s Orthopaedic
Sports Medicine. 3rd ed. 2009.
2. Levangie PK, Norkin CC. Joint Structure &
Function. 4th ed. 2005. 273-295.
3. Moore KL, Dalley AF, Agur AM. Clinically
Oriented Anatomy. 6th ed. 2010. 734-762.
Questions