ALLPPT.com _ Free PowerPoint Templates, Diagrams and Charts Elbow & radioulnar ROM ALLPPT.com _ Free PowerPoint Templates, Diagrams and Charts

Humeroulnar and Humeroradial Joints: the humeroulnar joint consists of the trochlea & the trochlear notch on the proximal ulna . the humeroradial joint consists of the capitulum and the radial head

Osteokinematics: The humeroulnar and humeroradial joints have 1 degree of freedom; flexion– extension occurs in the sagittal plane around a medial–lateral (coronal) axis. In elbow flexion and extension, the axis of motion lies approximately through the center of the trochlea. Arthrokinematics At the humeroulnar joint, posterior sliding of the concave trochlear notch of the ulna on the convex trochlea of the humerus continues during extension until the ulnar olecranon process enters the humeral olecranon fossa. In flexion, the ulna slides anteriorly along the humerus until the coronoid process of the ulna reaches the floor of the coronoid fossa of the humerus or until soft tissue in the anterior aspect of the elbow blocks further flexion.

At the humeroradial joint, the concave radial head slides posteriorly on the convex surface of the capitulum during extension. In flexion, the radial head slides anteriorly until the rim of the radial head enters the radial fossa of the humerus. Superior and Inferior Radioulnar Joints: The ulnar portion of the superior radioulnar joint includes both the radial notch located on the lateral aspect of the proximal ulna and the annular ligament. The radial notch and the annular ligament form a concave joint surface. The radial aspect of the joint is the convex head of the radius. The ulnar component of the inferior radioulnar joint is the convex ulnar head. The opposing articular surface is the ulnar notch of the radius.

The interosseous membrane, a broad sheet of collagenous tissue linking the radius and ulna, provides stability for both joints The following three structures provide stability for the superior radioulnar joint: the annular ligament, quadrate ligament, and oblique cord. Stability of the inferior radioulnar joint is provided by the articular disc and the anterior and posterior radioulnar ligaments

Osteokinematics The superior and inferior radioulnar joints are mechanically linked. Therefore, motion at one joint is always accompanied by motion at the other joint. The axis for motion is a longitudinal axis extending from the radial head to the ulnar head. have 1 degree of freedom, permitting the motions of pronation and supination in the transverse plane when the individual is standing in anatomical position. However, pronation and supination are usually measured with the elbow flexed to 90 degrees to isolate the motions at the forearm and prevent rotation from also occurring at the glenohumeral joint In pronation, the radius crosses over the ulna, whereas in supination the radius and ulna lie parallel to each other.

Arthrokinematics At the superior radioulnar joint, the convex rim of the radial head spins within the annular ligament and the concave radial notch of the ulna during pronation and supination. The articular surface on the radial head spins posteriorly during pronation and anteriorly during supination. At the inferior radioulnar joint, the concave surface of the ulnar notch on the radius slides over the ulnar head. The concave articular surface of the radius slides anteriorly (in the same direction as the hand) during pronation and slides posteriorly (in the same direction as the hand) during supination.

ELBOW FLEXION Motion occurs in the sagittal plane around a medial–lateral axis. Normal flexion ROM values for adults range from about 140 to 150 degrees.

Testing Position: Position the individual supine with the shoulder in 0 degrees of flexion, extension, and abduction so that the arm is close to the side of the body. Place a pad or towel roll under the distal end of the humerus to allow full elbow extension. Position the forearm in full supination with the palm of the hand facing the ceiling. Stabilization: Stabilize the humerus to prevent flexion of the shoulder. The pad under the distal humerus and the examining table prevents extension of the shoulder. Testing Motion: Flex the elbow by moving the hand toward the shoulder. Maintain the forearm in supination during the motion . The end of flexion ROM occurs when resistance to further motion is felt and attempts to overcome the resistance cause flexion of the shoulder.

Normal End-Feel Usually the end-feel is soft because of compression of the muscle bulk of the anterior forearm with that of the anterior upper arm. Goniometer Alignment: 1. Center fulcrum of the goniometer over the lateral epicondyle of the humerus. 2. Align proximal arm with the lateral midline of the humerus, using the center of the acromion process for reference. 3. Align distal arm with the lateral midline of the radius, using the radial head and radial styloid process for reference.

FOREARM PRONATION When the individual is in the testing position with the elbow flexed to 90 degrees, the motion occurs in the frontal plane around an anterior– posterior axis. Normal ROM values for adults range from about 75 to 85 degrees. Testing Position Position the individual sitting with the shoulder in 0 degrees of flexion, extension, abduction, adduction, and rotation so that the upper arm is close to the side of the body. Flex the elbow to 90 degrees and support the forearm. This testing position helps to isolate the motion to the forearm and prevent glenohumeral rotation.

Initially position the forearm midway between supination and pronation so that the thumb is aligned with the humerus; in most individuals the thumb will be pointing up toward the ceiling. Stabilization Stabilize the distal end of the humerus to prevent medial rotation and abduction of the shoulder.   Testing Motion Pronate the forearm by moving the distal radius in a volar direction so that the palm of the hand faces the floor. The end of pronation ROM occurs when resistance to further motion is felt and attempts to overcome the resistance cause medial rotation and abduction of the shoulder.

Normal End-Feel The end-feel may be hard because of contact between the ulna and the radius, or it may be firm because of tension in the dorsal radioulnar ligament of the inferior radioulnar joint, the interosseous membrane, and the supinator muscle.

Goniometer Alignment 1. Center fulcrum of the goniometer laterally and proximally to the ulnar styloid process. 2. Align proximal arm parallel to the anterior midline of the humerus. 3. Place distal arm across the dorsal surface of the forearm, just proximal to the styloid processes of the radius and ulna, where the forearm is most level and free of muscle bulk. The distal arm of the goniometer should be parallel to the styloid processes of the radius and ulna.

FOREARM SUPINATION When the individual is in the testing position with the elbow flexed to 90 degrees, the motion occurs in the frontal plane around an anterior– posterior axis. Normal ROM values for adults range from about 80 to 90 degrees. Stabilization Stabilize the distal end of the humerus to prevent lateral rotation and adduction of the shoulder.   Testing Motion Supinate the forearm by moving the distal radius in a dorsal direction so that the palm of the hand faces the ceiling The end of supination ROM occurs when resistance to further motion is felt and attempts to overcome the resistance cause lateral rotation and adduction of the shoulder.

Normal End-Feel The end-feel is firm because of tension in the palmar radioulnar ligament of the inferior radioulnar joint, oblique cord, interosseous membrane, and pronator teres and pronator quadratus muscles.   Goniometer Alignment 1. Place fulcrum of the goniometer medially and just proximally to the ulnar styloid process. 2. Align proximal arm parallel to the anterior midline of the humerus. 3. Place distal arm across the ventral surface of the forearm, just proximal to the styloid processes, where the forearm is most level and free of muscle bulk. The distal arm of the goniometer should be parallel to the styloid processes of the radius and ulna.