humerus

Examples of humerus in the following topics:

• Humerus (The Upper Arm)

  • The humerus is a bone in the upper arm.
  • Distally, the humerus articulates with the radius and ulna to form the elbow joint.
  • The proximal portion of the humerus can be divided into three parts.
  • Finally, the greater and lesser tubercles are found at the most superior end of the main shaft of the humerus.
  • Distally, the humerus flattens to articulate with the ulna and radius at the elbow joint.

• Muscles of the Humerus that Act on the Forearm

  • Humerus that act on the forearm are primarily involved in flexion and extension.
  • The humerus is a long bone in the arm that runs from the shoulder to the elbow.
  • Attachments - Originates from the scapula and attaches to the humerus.
  • Attachments - Originates from the humerus and attaches to the ulna.
  • Diagram the movements of the humerus muscles that act on the forearm

• Muscles of the Shoulder

  • The shoulder or glenohumeral joint is a ball and socket joint formed between the humerus and scapula.
  • The muscle converges into a tendon attaching to the humerus.
  • Intrinsic muscles originate from the scapula or clavicle and attach to the humerus.
  • Attachments – Originates from the posterior of the scapula and attaches to the humerus.
  • Both attach to the humerus.

• Muscles of the Wrist and Hand

  • Attachments - Originates from the humerus and attaches to the base of the hand.
  • Attachments - Originates from the humerus and attaches to the base of the digits.
  • Attachments - Originates from the humerus and attaches to the ulna.
  • Attachments - Originates from the humerus and attaches to the little finger.
  • Attachments - Originates from the humerus and attaches to the base of the hand.

• Scapula

  • The scapula, or shoulder bone, is a flat, triangular bone that connects to the humerus and the clavicle.
  • The scapula also articulates with the humerus of the upper arm to form the shoulder joint, or glenohumeral joint, at the glenoid cavity.

• Ulna and Radius (The Forearm)

  • The forearm contains two bones—the radius and the ulna—that extend in parallel from the elbow, where they articulate with the humerus to the wrist, where they articulate with the carpals.
  • The cornoid process, together with the olecranon, forms the trochlear notch where it articulates with the trochlea of the humerus.
  • Proximally, the radius terminates with a disk-shaped head that articulates with the capitulum of the humerus and the radial notch of the ulna.

• Rotator Cuff Injury and Dislocated and Separated Shoulder

  • The main functions of the cuff are to stabilize the glenohumeral joint and rotate the humerus outward.
  • In a typical case of a dislocated shoulder, a strong force that pulls the shoulder outward (abduction) or extreme rotation of the joint pops the ball of the humerus out of the shoulder socket.
  • Doctors treat a dislocation by putting the head of the humerus back into the joint socket (glenoid fossa) of the scapula.
  • X-ray of a complete tear of the supraspinatus resulting in a shift upwards of the head of the humerus.

• The Appendicular Skeleton

  • Upper arms and forearms (6 bones) - Left and right humerus (upper arm, 2), ulna (2) and radius (2) (forearm)
  • The three regions of the upper limb arm (humerus), forearm (ulna medially and radius laterally), and the hand.

• Lever Systems

  • The force is applied at its point of insertion on the ulna in the forearm, the elbow is the pivot, and the load is the humerus in the upper arm.
  • Internal rotation can also move the humerus and femur inward.
  • External or lateral rotation is the opposite movement, pointing the distal portion of limbs as well as the humerus and femur away from the mid-line.

• Impingement Syndrome

  • The rotator cuff muscle tendons pass through a narrow space between the acromion process of the scapula and the head of the humerus.
  • Loss of function of the rotator cuff muscles, due to injury or loss of strength, may cause the humerus to move superiorly, resulting in impingement.