There are 30 bones in each upper limb. The humerus is the single bone of the upper arm, and the ulna medially and the radius laterally are the paired bones of the forearm. The base of the hand contains eight bones, each called a carpal bone , and the palm of the hand is formed by five bones, each called a metacarpal bone.
The fingers and thumb contain a total of 14 bones, each of which is a phalanx bone of the hand. The humerus is the single bone of the upper arm region Figure 6. At its proximal end is the head of the humerus. This is the large, round, smooth region that faces medially. The head articulates with the glenoid cavity of the scapula to form the glenohumeral shoulder joint.
The margin of the smooth area of the head is the anatomical neck of the humerus. Located on the lateral side of the proximal humerus is an expanded bony area called the greater tubercle.
The smaller lesser tubercle of the humerus is found on the anterior aspect of the humerus. Both the greater and lesser tubercles serve as attachment sites for muscles that act across the shoulder joint. The deltoid tuberosity is a roughened, V-shaped region located on the lateral side in the middle of the humerus shaft. As its name indicates, it is the site of attachment for the deltoid muscle. Distally, the humerus becomes flattened. The prominent bony projection on the medial side is the medial epicondyle of the humerus.
The much smaller lateral epicondyle of the humerus is found on the lateral side of the distal humerus. All of these areas are attachment points for muscles that act on the forearm, wrist, and hand. The powerful grasping muscles of the anterior forearm arise from the medial epicondyle, which is thus larger and more robust than the lateral epicondyle that gives rise to the weaker posterior forearm muscles.
The distal end of the humerus has two articulation areas, which join the ulna and radius bones of the forearm to form the elbow joint. The capitulum articulates with the radius bone of the forearm.
Just above these bony areas are two small depressions. These spaces accommodate the forearm bones when the elbow is fully bent flexed. Superior to the trochlea is the coronoid fossa , which receives the coronoid process of the ulna, and above the capitulum is the radial fossa , which receives the head of the radius when the elbow is flexed.
Similarly, the posterior humerus has the olecranon fossa , a larger depression that receives the olecranon process of the ulna when the forearm is fully extended. The ulna is the medial bone of the forearm. Severe fractures may require surgical immobilization, while minor fractures might be able to be immobilized through manipulation and a cast or splint.
After immobilization, long-term rehabilitation includes physical therapy. A physical therapist will be able to teach the patient stretching and strengthening exercises that put the right amount of pressure on the right areas following a fracture.
Physical therapy may also be necessary for the shoulder due to the immobilization of the injured arm. Not being able to use the forearm means the patient likely isn't moving her shoulder much either. Surgical repair or reduction of severe fractures may take more than one surgery to fully repair the injury. Each surgery requires a healing period and the patient may need physical therapy to return to pre-surgical function. It might be several months between surgical procedures for some injuries, requiring a rehabilitation process after each procedure.
Rehabilitation for fractures of the radius could take two to three months to fully heal back to pre-injury functionality. It's important to comply with physical therapy and stay up to date on all exercises and treatment modalities. Long delays between sessions or the lack of performing exercises outside of the physical therapy office can inhibit healing or even lead to repeat injury.
Proximal refers to a part of the body that is closer to a point of attachment, while distal is further from a point of attachment. They act as opposites of each other. For example, the shoulder is more proximal to the body, while the hand is more distal.
The diaphysis is a term used to define the shaft of a long bone, such as the radius. The space inside of a diaphysis is called the medullary cavity, which is filled with bone marrow. The end of a long bone is called the epiphysis. Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. Acta Orthop. Sex determination and estimation of stature from the long bones of the arm.
Forensic Sci Int. Anatomy, shoulder and upper limb, forearm radius. Updated July 14, The epidemiology of distal radius fractures. Hand Clin. Pediatric distal forearm and wrist injury: an imaging review. American Academy of Orthopaedic Surgeons. Adult forearm fractures. Updated July, Updated October 5, Proximal radius fracture morphology following axial force impact: a biomechanical evaluation of fracture patterns. BMC Musculoskelet Disord.
Your Privacy Rights. The curve that it forms is called the trochlear notch. It articulates with the trochlea of the humerus. The very proximal end of the ulna is the olecranon.
The triceps tendon is attached to it. This projection is the coronoid process. Distal to it this rough area, the ulnar tuberosity, marks the insertion Distal to it this rough area, the ulnar tuberosity, marks the insertion of the brachialis tendon. This small curved surface, the radial notch, is where the head of the radius articulates. This is the head of the radius, This is the neck. The end of the head articulates with the capitulum of the humerus. Just distal to the neck is the radial tuberosity, which is the insertion for the biceps tendon.
Sign up for free, and stay up-to-date on research advancements, health tips and current health topics, like COVID, plus expert advice on managing your health. Error Email field is required. Error Include a valid email address. To provide you with the most relevant and helpful information and to understand which information is beneficial, we may combine your e-mail and website usage information with other information we have about you.
If we combine this information with your PHI, we will treat all of that information as PHI, and will only use or disclose that information as set forth in our notice of privacy practices.
You may opt-out of e-mail communications at any time by clicking on the Unsubscribe link in the e-mail. Our Housecall e-newsletter will keep you up-to-date on the latest health information.
0コメント