Monika Kumar

 Anatomy of Bone: Elbow Student name : Student ID : Course : Date: Elbow is a joint with prominent benchmarks comprising olecranon, medial, lateral epicondyles and elbow pit.Components of elbow joint- Part 1: Joint Anatomy Bony Prominences (lumps, bumps, grooves) Elbow is articulation of three bones- 1) Humerus- long bone connecting shoulder and elbow 2) Radius- forearm bone (on thumb side) connecting elbow and wrist 3) Ulna- forearm bone (on pinky finger side) between elbow and wrist, runs next to radius Bumps or bony prominences at the bottom of humerus encompass epicondyles. Bump on outer side is called lateral epicondyle (OrthoInfo, n.d.). Joints Elbow joint issynovial joint or diarthroses or functionally a free moving joint called hinge joint, facilitating movement in one plane i.e., uniaxial. Elbow has three articulations- 1) Humeroulnar- it is a hinge joint between trochlea on medial aspect of distal end of humerus and trochlear notch on proximal ulna. 2) Humeroradial- present between capitulum on lateral aspect of distal end of humerus with radius head. 3) Proximal radioulnar- it is a trochoid joint that facilitates pivot motion translated in pronation and supination. Proximal ends of ulna and radius articulate with each other at this joint. Elbow extends between 0 and 140º and rotate to 80º. For all activities, flexion and extension rangeof 30-130º and rotation of 50º are required (Martin and Sanchez., 2013). Ligaments 1) Ulnar Collateral Ligament (UCL) complex- expands from medial epicondyle of humerus to coronoid process of ulna. 2) Radial collateral ligament (RCL) attached to lateral epicondyle of humerus. 3) Lateral Collateral Ligament (LCL)- composed of lateral ulnar collateral ligament (LUCL). 4) Annular ligament and also accessory lateral collateral ligament- holds radius and ulna together at proximal articulation 5) Quadrate ligament- upholds constant tension in supination and pronation of forearm(Lombardi et al., 2020). Cartilage coverage between trochlea is 330º and that of capitellum is 180º, noteworthily, coverage ends suddenly in its posterior contour. This is designated as pseudo defect of capitellum (Rosenberg at al., 2008). Tendon 1) Tendon of long head of biceps- inserts proximal to short head and lodges greater part of radial tuberosity. 2) Superficial layers of biceps tendon amalgamate with medial muscle bulk of proximal forearm of elbow to create bicipital aponeurosis or lacertus fibrosus. Other components include lateral collateral ligament, humeral supracondylar ridge, supinator crest of ulna (Morrey., 2012). Nerves 1) Radial- passes between brachioradialis and brachial muscles, nerve bifurcates into superficial sensory as well as deep motor branches. 2) Ulnar- passes posterior to medial epicondyle inner to the cubital tunnel roofed by Osborne’s ligament. Median- passes between brachial muscles and lacertus fibrosus and between two heads of pronator teres muscles (Andreisek et al., 2006). Movement Elbow is a hinge joint, with movement in one plane. 1) Flexion of forearm- reduction in angle between forearm and arm. Extension- increase in the angle between forearm and arm (Lombardi et al., 2020). Bursa(e) Bursa is a small fluid-filled sac surrounded by synovial membrane filled with viscous synovial fluid, provides cushion between tendons and bones. Tip of elbow has olecranon bursa; this is a fluid filled sac which serves as a cushion facilitating smooth movement at joint. Inflammation comprising redness, swelling and pain in this bursa is designated as olecranon bursitis (Nchinda and Wolf., 2021). Student’s Comments The anatomy of elbow muscles is complex and therefore detailed knowledge of bones, joints and ligaments is important to understand. The above information will help in providing an understanding about the anatomy of elbow joint. Instructor’s Comments/ Grade Part 2: Muscle Anatomy Muscles Muscles surrounding elbow are magnificent stabilizers. Elbow joint movement is facilitated by- 1) Biceps brachii- helps in supination. Itinserts distally onto bicipital tuberosity of radius. Large muscle of upper arm, flexes arm, twists forearm and turns the palm upward. 2) Brachialis- originates from anterior surface of humerus and insert into ulnar tuberosity. It aids in flexing elbow inward towards body. 3) Brachioradialis- These are primary elbow flexors. The muscle flexes the arm at elbow. 4) Triceps brachii-inserts distally onto olecranon bearing intricate footprint anatomy. Medial head of triceps possess a muscular insertion deep into olecranon. They are primary extensors, present at the back of upper arm. Helps in extending the arm and stabilizes elbow for fine movements. 5) Anconeus- originates in lateral humeral epicondyle while it inserts in olecranon. Itaids in extending forearm at elbow. 6) Medial muscle group- brings flexion-pronation of forearm. It encompasses six set of muscles- a) Pronator teres are leading muscles for pronation and help flex the elbow. They extend from humerus head over elbow to ulna bone. b) Flexor digitorum superficialis (FDS) c) Flexor carpi radialis (FCR) d) Palmaris longus (PL) e) Flexor carpi ulnaris (FCU) f) Flexor digitorum profundus (FDP) 7) Lateral muscle group brings extension-supination of forearm (Lombardi et al., 2020). Student’s Comments Muscles are important for the movement of the skeletal system. Contraction and relaxation of muscles helps in performing different tasks. Proper understanding of the muscles of elbow joint is important to understand any ailment related to the muscles of elbow joint. Instructor’s Comments/ Grade Part 4: Reflection Interesting Facts or other soft tissue structures Elbow is prone to chronic mechanical stress and trauma especially in athletes and children. Common ailments associated with elbow are- neuropathy, joint dislocation, fracture of elbow bones, osteochondrosis, lesions in elbow ligaments, osteochondritis dissecans, bursitis and abnormalities related to tendons.Understanding anatomy and biomechanics helps in appropriate evaluation and diagnosis (Lombardi et al., 2020). Tennis elbow is common in athletes, it is a painful condition of tendons caused by overuse of hands. Moreover, in today’s contemporary world where desk work is more, constant use of computers and mobile phones keep hands in the same position all through the day, this eventually leads to ulnar nerve compression and neuropathy associated with elbow joint. Describe in your own words to 80-yr-old client Elbow fracture is challenging to treat especially perfect restoration of soft tissues should be appropriately identified and managed. Knowledge of normal bone anatomy is imperative for internal fixation, reconstruction and repair of collateral ligaments (Midtgaard et al., 2020). People must understand the anatomical complexities of the elbow joint and should take proper care to prevent any injuries especially in old age when healing diminishes remarkably. Student’s Comments Reflection: What: The anatomy of elbow joint is intricate, proper understanding of bones, muscles, ligaments, tendons and nerves is important to understand. So What: Elbow joint is prone to injuries and therefore it is important for people of all ages especially athletes, children and elders, to understand the anatomy of the joints to some extent so that any ailment, pain, inflammation associated with the joint could be treated well in time. What Next: The article is an attempt to highlight all the important aspects related with the elbow joint. An illustration will help in generating understanding about the anatomy of elbow joint to facilitate appropriate care. Instructor’s Comments/ Grade References Andreisek, G., Crook, D. W., Burg, D. et al. (2006). Peripheral neuropathies of the median, radial and ulnar nerves: MR imagining features. Radiographics. 26,-. Lombardi, A., Ashir, A., Gorbachova, T., Taljanovic, M. S., Chang, E. Y. (2020). Magnetic resonance imaging of the elbow. Pol J Radiol. 85, e440-e460. Martin, S., Sanchez, E. (2013). Anatomy and biomechanics of the elbow joint. Semin MusculoskeletRadiol.17, 429-436. Midtgaard, K. S., Ruzbarsky, J. J., Hackett, T. R., Viola, R. W. (2020). Elbow Fractures. Clin Sports Med. 39(3), 623-636. Morrey, B.F. (2012). Reconstruction of the posterior bundle of the medial collateral ligament: a solution for posteromedial olecranon deficiency- a case report. J Shoulder Elbow Surg.21, e16-19. Nchinda, N. N., Wolf, J. M. (2021). Clinical Management of Olecranon Bursitis: A Review. Hand Surg Am. 46(6), 501-506. OrthoInfo. (n.d.). Elbow Fractures in Children. Retrieved from https://www.orthoinfo.org/en/diseases--conditions/elbow-fractures-in-children/ Rosenberg, Z. S., Blutreich, S. I. Schweitzer, M. E., et al. (2008). MRI features of posterior capitellar impaction injuries. AJR Am J Roentgenol. 190, 435-441.