Radiography of the Forearm and Elbow Lecture Notes PDF

RMI 221 Radiographic Anatomy & Positioning 1 Lecture 5 Radiography of the Forearm and Elbow fchs.ac.ae Learning Outcomes After today’s lecture you will be able to: Identify the key anatomical points of the forearm and elbow. Identify the com...

RMI 221 Radiographic Anatomy & Positioning 1 Lecture 5 Radiography of the Forearm and Elbow fchs.ac.ae Learning Outcomes After today’s lecture you will be able to: Identify the key anatomical points of the forearm and elbow. Identify the common reasons for performing forearm and elbow radiography. Explain the key considerations in patient assessment and preparation for forearm and elbow radiography. List all of the routine projections for forearm and elbow radiography. Explain the movement of the arm required to obtain optimal projections. Describe the positioning methods for routine and supplementary projections of the forearm and elbow. Discuss how to overcome the radiographic challenges present with radiography of the forearm and elbow. fchs.ac.ae Reading The prescribed text relating to this lecture is: Bontrager, K.L. & Lampignano, J.P. (2010), Textbook of Radiographic Positioning and Related Anatomy, 7th edition, Mosby, St. Louis, Missouri. The prescribed reading is: Bontrager, K. & Lampignano, J. (2010), Textbook of Radiographic Positioning and Related Anatomy, 7th edition, Mosby, St. Louis, Chapter 5, pp.160-169. fchs.ac.ae Overview 1. Basic principles revisited 2. Radiography of the forearm – Anatomical points – Clinical indications Fractures – Protocols: Radiographic projections – Technique – Patient preparation – Radiographic positioning – Radiographic challenges 3. Radiography of the elbow – As above fchs.ac.ae Basic Principles Revisited: Radiography of the Forearm and Elbow How many minimum projections are required for: 1. Radiography of the forearm? 2. Radiography of the elbow? fchs.ac.ae Radiography of the Forearm  Radiography of the Forearm Anatomical points Clinical indications – Fractures – Dislocations – Pathology (such as Osteoarthritis and Osteomyelitis) Protocols: radiographic projections Technique Pre-examination assessment and preparation of patient Positioning of the patient – Standard – Special considerations fchs.ac.ae Radiography of the Forearm: Anatomical Points Fig 5-14, Bontrager & Lampignano (2005), p.134. fchs.ac.ae  Radiography of the Forearm: Anatomical Points (continued) Head of radius is at the elbow. Head of ulna is at the wrist. The actions of supination and pronation involve rotation of the radius and the hand, the ulna does not move. Fig 5-25 ,Bontrager & Lampignano (2005), p.138. fchs.ac.ae Radiography of the Forearm: Anatomical Points (continued) During pronation, the radius crosses the ulna at the upper third of the forearm which is why an anatomical AP projection is required. Fig 5-25, Bontrager & Lampignano (2005), p.138. fchs.ac.ae Radiography of the Forearm: Clinical Indications Types of fractures range Galeazzi # + dislocation from stable and undisplaced oblique # of the radial to unstable and displaced: shaft but also involves the Torus fracture distal radio-ulnar joint (requires radiograph of Metaphyseal fracture the forearm) Greenstick fracture the ulna remains intact; Growth plate fracture the distal radio-ulnar joint Galeazzi fracture dislocates Texas Scottish Rite Hospital for Children Monteggia fracture fchs.ac.ae The Monteggia fracture: is a fracture of the proximal third of the ulna with dislocation of the proximal head of the radius. (Weissman & Sledge,1986, p.201.) fchs.ac.ae A growth plate fracture: is a break in the growth plate of a child or teen. They happen most often in the bones of the fingers, forearm, and lower leg. fchs.ac.ae  Greenstick fracture: Found almost exclusively in infants and children because of the softness of their cancellous bone. - contrecoup injury or fracture occurs on the side opposite the area that was hit. -Must include wrist and elbow. –Also other fractures of the distal humerus or wrist may occur simultaneously. fchs.ac.ae  Classic Galeazzi fracture: is a fracture at the junction of middle and distal thirds of the radius with dislocation or subluxation of the distal radio- ulnar joint (Weissman & Sledge,1986, p.201.) radiopaedia.org fchs.ac.ae  Radiography of the Forearm: Protocols – Radiographic Projections Standard radiographic projections: AP – To demonstrate the entire radius and ulna, proximal row of carpal bones, distal of humerus, soft tissue such as fat pads, as well as elbow and Fig 5-115, Bontrager & Lampignano (2010), p.160. wrist joints. Lateral – Anatomy will be demonstrated as above, in lateral position. Fig 5-118, Bontrager & Lampignano (2010), p.161. fchs.ac.ae Radiography of the Forearm: Technique (continued) Exposure factor selection: 60 kVp 100 cm SID/FFD Small focal spot Collimation - Collimate both lateral borders to actual forearm area. - Collimate at both ends to avoid cuttings off anatomy at either joint. - Ensure minimum of 3 to 4cm distal to wrist and elbow joints included on IR. fchs.ac.ae  Radiography of the Forearm: Patient Preparation Your patient may present with the arm in a sling: – “Do we remove it?” Artifacts should be removed - for example, clothing, sling. Remove jewellery/roll up sleeves: – You may have to get patient to take arm out of the shirt/blouse/sweatshirt, etc. Fig 5-34, Bontrager & Lampignano (2010), p.134. Radiation protection- Shielding outside region of interest. fchs.ac.ae  Radiography of the Forearm: Patient Positioning AP Patient seated at the end of the table. Hand extend and palm up (supinated). Arm is abducted and fully extended. Patient may need to lean well back in the chair. Shoulder, elbow and wrist need to be in the same plane. Medial and lateral epicondyles are equidistant from the cassette/IR. Fig 5-118, Bontrager & Lampignano (2005), p.166. CR perpendicular to the IR, directed to mid- forearm. fchs.ac.ae Essential image characteristics Long axis of forearm should be aligned to long axis of IR. Both the elbow & the wrist joint must be demonstrated on the IR Both joints should be seen in the true AP position, with the radial & ulnar styloid processes & the epicondyles of the humerus equidistant from the IR. Note: PA projection of the forearm with the wrist pronated is not satisfactory because, in this projection, the radius is superimposed over the ulna for part of its length. 20 Radiography of the Forearm: Patient Positioning (continued) Lateral Patient flexes elbow to a right angle (90°). Adjust the arm into a lateral position with hand and wrist lateral. Arm is true lateral if a line joining the epicondyles of the humerus is at right angles to the table. CR perpendicular to the lateral aspect of the forearm mid way between the elbow and wrist Fig 5-117, Bontrager & Lampignano (2010), p.161. fchs.ac.ae Radiography of the Forearm: Patient Positioning (continued) In the lateral projection: Radius and ulna will be superimposed at their distal end. Humeral epicondyles should be superimposed. It is sometimes routine to only include the joint nearest the site of injury. fchs.ac.ae  Essential image characteristics Both the elbow & the wrist joints must be showen on the image Both joints should be seen in the true lateral position, with the radial & ulnar styloid processes and the epicondyles of the humerus superimposed. Notes: In trauma cases, it may be impossible to move the arm into the positions described, If the limb cannot be moved through 90°, then a horizontal beam should be used. Both joints should be included on each image. No attempt should be made to rotate the patient’s hand. 23 Radiography of the Forearm: Right Forearm Example Lateral AP fchs.ac.ae Radiography of the Forearm: Left Forearm Example (Foreign Body) fchs.ac.ae  Radiography of the Forearm: Radiographic Challenges Consider requests for wrist and forearm: Post reduction radiographs of wrist and forearm in Plaster of Paris (POP). Depending upon the fracture, www.cksu.com the plaster may place the wrist into an unusual shape. – positioning for the lateral projection fchs.ac.ae Radiography of the Forearm:Radiographic Challenges(continued) Requests for wrists and forearms when patients are in casts: (full cast) will not be able to supinate the forearm. Increase exposure factors POP wet vs dry. May not need to change factors if a fiber glass cast is used. Fig 18-39, Bontrager & Lampignano (2010), p.601. fchs.ac.ae Radiography of the Forearm: Left Forearm Pediatric Example 1 fchs.ac.ae Radiography of the Forearm: Right Forearm Pediatric Example 2 fchs.ac.ae Radiography of the Elbow Radiography of the Elbow Overview Anatomical points Clinical indications – Fractures – Dislocations – Other Protocols: Radiographic projection Technique fchs.ac.ae Radiography of the Elbow (continued) Overview (continued): Pre-examination assessment/preparation of patient Positioning of the patient – Standard/routine – Supplementary – Special considerations fchs.ac.ae Radiography of the Elbow: Anatomical Points Fig 5-17, Bontrager & Lampignano (2005), p.135. Fig 5-16, Bontrager & Lampignano (2005), p.135. fchs.ac.ae  Radiography of the Elbow: Anatomical Points (continued) Different oblique projections to demonstrate the coronoid process of the ulna and head of the radius. Standard lateral projection of the elbow will demonstrate the olecranon process of the ulna. Consider additional projection if the olecranon is the area of clinical interest. Fig 4-66, McQuillen Martensen (2011), p.223. fchs.ac.ae  Radiography of the Elbow: Anatomical Points (continued) Fracture of the radial head common: Can be missed so must include:a variety of projections “radial head” Coyle projection. (Bontrager & Lampignano, 2010, p.168) fchs.ac.ae  Radiography of the Elbow: Anatomical Points (continued) Anterior and posterior fat pads: Located between the fibrous capsule and the synovial membrane. Significant in that they allow Fig 4-77, McQuillen Martensen (2011), p.233. evaluation of joint distension. fchs.ac.ae Radiography of the Elbow: Anatomical Points (continued) The single posterior fat pad overlies the olecranon fossa and is pressed into the fossa when the arm is flexed: – therefore very hard to see. radiopaedia.org fchs.ac.ae Activity: Anatomical Points – Quick poll C= Anterior fat pad E= Superior fat pad D= Posterior fat pad Fig 5-32, Bontrager & Lampignano (2005), p.139. fchs.ac.ae Radiography of the Elbow: Clinical Indications Common area of trauma Fractures – Supracondylar – Condylar/epicondylar – lateral or medial – Radial head or neck – Olecranon Dislocations Other – RSI aka tennis or golfer’s elbow supracondylar fracture – Tumours fchs.ac.ae Radiography of the Elbow: Left Elbow Supracondylar Fracture Series fchs.ac.ae Radiography of the Elbow: Lateral Condylar/epicondylar Fracture fchs.ac.ae Radiography of the Elbow: Radial head or neck Fracture Radial Head fchs.ac.ae Radiography of the Elbow: Patient Preparation Elbow injuries are particularly painful – patient may be reluctant to extend arm. Listen to the patient – never force a patient’s arm into position. Demonstrate what you would like the patient to do, then encourage the patient to position their arm. fchs.ac.ae Radiography of the Elbow: Patient Preparation (continued) Artifacts should be removed - for example, clothing, sling. Children: Dislocation or supracondylar fracture Adults: Radial head fracture or RSI http://www.remecare.co.uk/acatalog/Arm_Slings _Supports.html fchs.ac.ae Radiography of the Elbow: Elbow in a Half Plaster (Slab) fchs.ac.ae Radiography of the Elbow: Technique (continued) Need maximum recorded detail 60-70 kVp 100cm SID/FFD Nongrid fchs.ac.ae Radiography of the Elbow: Protocols - Radiographic Projections Routine: three or four projections: AP AP oblique lateral- (external rotation), Primarily for injury of the Radial head. AP oblique medial (Internal rotation), primarily for injury Coronoid process. Lateral with wrist in lateral position fchs.ac.ae Radiography of the Elbow: Protocols - Radiographic Projections (continued) Special considerations: Modifications made when elbow is in various degrees of Flexion. Supplementary: Other laterals with differing degrees of wrist rotation Coyle’s method/projection Coronoid process fchs.ac.ae Radiography of the Elbow: Protocols - Radiographic Projecti (continued) Routine or standard radiographic projections Use the following protocol assuming the patient can extend the elbow: AP and lateral – to include proximal third of radius and ulna and distal third of the humerus with the elbow joint in the centre of the cassette AP oblique- lateral (external) rotation AP oblique- medial – for head of radius (Internal) rotation – usually considered to be a – for coronoid process routine/standard projection – requires above criteria fchs.ac.ae AP Projections Elbow fully extend Elbow Partially flexed - Two projections: 1. Distal Humerus 2. Proximal Forearm Elbow in Acute flexion (Jones method) - Two projections: 1. Distal Humerus 2. Proximal Forearm AP projection of the Elbow- Fully extend AP: Assuming the patient can extend the elbow: Fig 5-119, Bontrager & Lampignano (2010), p.162. As per AP forearm – But CR must be directed to the elbow joint – approximately 2 cm distal to the mid point of a line between the epicondyles of the humerus Collimate to the area Fig 5-123, Bontrager & Lampignano (2005), p.168. fchs.ac.ae  AP projection of the Elbow- partially flexed AP: patient cannot fully extend (elbow partially flexed) Is the clinical problem in the area of the distal humerus or the proximal forearm? -Obtain two AP projections, one with forearm parallel to IR, and one with humerus parallel to IR. Fig 5-122, Bontrager & Lampignano (2010), p.163. fchs.ac.ae AP: Elbow partially flexed Distal humerus: Posterior aspect of the Fig 5-122, Bontrager & Lampignano (2010), p.163. upper arm in contact with the cassette CR perpendicular/ vertical – Midway between epicondyles of humerus – 2.5 cm distal to crease of elbow Fig 5-124, Bontrager & Lampignano (2010), p.163. fchs.ac.ae AP: Elbow partially flexed Proximal forearm: Posterior part of the Fig 5-123, Bontrager & Lampignano (2010), p.163. proximal forearm in contact with the cassette CR perpendicular – Midway between epicondyles of humerus – 2.5 cm distal to crease of elbow Image 81, McQuillen Martensen (2011), p.228. fchs.ac.ae Radiography of the Elbow: Left Elbow Example fchs.ac.ae AP projection of the Elbow- Acute flexion AP: When patient presents with acute flexion of the elbow Jones method (Option A)- for distal humerus – Posterior aspect of the distal humerus in contact with the cassette. – CR perpendicular to humerus 5 cm superior to olecranon process (distal humerus). – No tube angulation involved Figs 5-137 & 5-139 ,Bontrager & Lampignano (2010), p.167. fchs.ac.ae AP projection of the Elbow- Acute flexion AP: When patient presents with acute flexion of the elbow Jones method (Option B)- for proximal forearm – Posterior aspect of the distal humerus in contact with the cassette. CR placement: – Angle the tube so CR is perpendicular to proximal forearm. – Position 5 cm distal to the olecranon process Figs 5-138 & 5-140, Bontrager & Lampignano (2010), p.167. fchs.ac.ae Radiography of the Elbow: Left Elbow Trauma - Olecranon Fracture fchs.ac.ae Radiography of the Elbow- Lateral (lateromedial) projection Lateral: Same positioning for lateral forearm CR must be directed to the mid Fig 5-134 ,Bontrager & Lampignano (2010), p.166. elbow joint Mid point approximately 4 cm medial to the posterior surface of the olecranon process Collimate to the area Fig 5-134, Bontrager & Lampignano (2010), p.166. fchs.ac.ae Radiography of the Elbow: AP Oblique projection- Lateral (External) rotation AP Oblique: For radial head and neck free from superimposition Arm AP then further rotate hand laterally to place the posterior surface of the elbow at an angle of 400 – When the correct degree of rotation is achieved, thumb and 2nd digit should touch table CR perpendicular to elbow joint Fig 5-128, Bontrager & Lampignano (2010), p.164. fchs.ac.ae Radiography of the Elbow: AP Oblique projection- Medial (Internal) rotation To demonstrate an injury to the coronoid process of the ulna. Figs 5-131 & 5-132, Bontrager & Lampignano (2010), p.165. – Arm AP then rotate hand medially or pronate the hand placing the anterior surface of the elbow at an angle of 40 – 450 – CR perpendicular to elbow joint Fig 5-136, Bontrager & Lampignano (2005), p.171. fchs.ac.ae Supplementary projections Radial head laterals Axial lateromedial projections: (Coyle method for Radial head) (Coyle method for coronoid process) Supplementary projections Radial Head Laterals- with different rotation of hand and wrist Lateromedial projection For the demonstration of an injury to the of the radial head with head of the radius: Hand Pronated A series of lateral projections to show the radial head and neck in profile with the hand in a variety of positions The position of the radial tuberosity identifies hand position Lateromedial projection of the radial head with Hand in maximum internal rotation fchs.ac.ae Supplementary projections Axial Lateromedial projections/ Coyle method for Radial head - To demonstrate injury of the radial head Fig 5-143 ,Bontrager & Lampignano (2010), p.168. - Injury to wrist with referred pain in elbow - “classic sign” Coyle Method – “Radial head view” – Lateral elbow flexed at 900 – Hand pronated – CR angulation between 25 - 450 to the shoulder, into the mid-elbow joint. Fig 4-84, McQuillen Martensen (2011), p.240. fchs.ac.ae Radiography of the Elbow: Right Elbow Example - Radial Neck Fracture fchs.ac.ae Supplementary projections Axial lateromedial projection/ Coyle method for Coronoid process To demonstrate an injury to the coronoid process of the ulna Figs 5-144 & 5-148, Bontrager & Lampignano (2010), p.168. Lateral modified – Elbow flexed 80° – hand pronated (latero- medial) – CR angled 45° away from Shoulder, into mid-elbow joint. Fig 5-153, Bontrager & Lampignano (2005), p.172. fchs.ac.ae