Biceps Tendon Rupture With Post-operative Complications

Biceps Tendon Rupture With Post-operative Complications Locomotor PBL Experiment Writeup Introduction In this PBL, we observe a case of biceps tendon rupture with post-operative complication of heterotopic ossification. We will first go through the anatomy of the upper limb followed by a discussion of the ruptured biceps tendon, heterotopic ossification and finally mode of action of indomethacin. Learning Objectives 1. Osteology of the upper limb with emphasis on the elbow and wrist 2. The neurovascular supply to the upper limb 3. Movements possible at joints of upper limb and the range of movements possible with regards to the elbow and wrist and the muscles that bring about these actions. 4. Rupture of distal biceps tendon 5. Heterotopic ossification 6. Mode of action of Indomethacin 1. Osteology of the upper limb with emphasis on the elbow and wrist Arm The humerus is the largest and longest bone of the arm region connecting the shoulder to the forearm. Proximally, the head of the humerus articulates with the glenoid cavity of the sca pula forming the glenohumeral joint. Distally the humerus articulates with the two bones of the forearm, the ulna and radius. The humerus is shown in more detail in figure 1 below. Figure 1 Humerus (1) For Anil’s case we will focus several prominent features on the distal region of the humerus which forms part of the elbow. There are two projections on either side of the distal end of the humerus which are the medial and lateral epicondyle. The medial epicondyle protects the ulnar nerve which passes just posteriorly and also serves as the attachment site for the forearm superficial flexor muscles. The lateral epicondyle conversely is the attachment site for the forearm extensor muscles. Anteriorly in between these two epicondyles are two articular surfaces: the round surfaced lateral capitulum which articulates with the radius and the spool shaped medial trochlea which articulates with the ulna. Also anteriorly, the radial fossa directly above the capitulum accommodates the h ead of the radius during flexion of the elbow whereas the coronoid fossa directly above the trochlea accommodates the coronoid process of the ulna during flexion of the elbow. Both the radial and coronoid fossa limit flexion of the elbow. Posteriorly, the olecranon fossa accommodates the olecranon process of the ulna during extension of the elbow. The olecranon fossa prevents hyperextension of the elbow. Forearm The forearm is made up of two bones: ulna and radius. Proximally both of these bones articulate with the humerus whereas distally only the radius directly articulates with the carpals of the wrist thus connecting the arm to the wrist. The ulna and radius are shown in figure 2 below. Figure 2 Radius and Ulna (1) The ulna The ulna is the stabilizing bone of the forearm and is medial and longer of the two bones. There is a projection anteriorly at the proximal end called the coronoid process which fits into the coronoid fossa during elbow extension. Posteriorly on the proximal end of the ulna is the olecranon process (which forms the prominence of the elbow) which fits into the olecranon fossa during elbow extension. The articular surface between the olecranon and the coronoid articulates with the trochlear of the humerus and gives the movements of elbow extension and flexion.