Scanning Sequence * Anterior Joint (The anterior Pyramid ) * Lateral Epicondyle * Medial Epicondyle * Posterior Joint Anterior Elbow Pyramid Courtesy of Jay Smith, MD. Vice chair PMR Mayo Clinic Rochester, MN Short axis probe placement at the antecubital fossa Biceps Anterior Elbow Pyramid The Surrounding Musculature Radial Head r Notch Anterior Elbow Pyramid Anterior Compartment Effusion Fat Pad Displacement Brachial Artery Supine patient Bolus under hand to limit extension = = Brachioradialis Cap Troch = Pronator Teres = Radial Nerve = Artery w MN Troch Short axis scan through the Humeral Coronoid Fossa may reveal fat pad displacement as seen with occult fracture. 90 degree flexion with light probe pressure is helpful. 1
Anterior Transverse: Anterior Approach The two heads of Biceps Brachii unite forming a thick tendon, attaching at the Radial Tuberosity. Transverse probe at the crease Antecubital Fossa. Transverse Orientation Anterior Longitudinal Orientation Lateral Biceps Slight proximal beam angulation helps visualize the hyperechoic tendon in cross-section Biceps tendon is centrally positioned on TOP of the LAX probe angled Radially Medial Tracking the Biceps tendon to it s Radial attachment requires firm probe contact, and can be difficult due to anisotropy Longitudinal Orientation Panoramic Image Bic Cap Radial Head Long Axis Radial Beam Anisotropy presents due to oblique, deeper course to the attachment on the Radial Tuberosity. Slight lateral probe translation reveals Capitulum & Radial Head. Tracing Radial cortex to the tuberosity may visualize tendon attachment. 2
Anterior Longitudinal (Medial Probe Angle = tendon ) 1 3 2 Lateral Approach attachment Probe Angled medially 1 = Humeral Trochlea 2 = Coronoid Process of Arrow: attachment 3 = Pronator Teres Muscle Lateral Approach to the Lateral Approach : Image Orientation Diagram Courtesy Jon Jacobson, MD Extensors Superficial Supinator T = Probe 90 degree elbow flexion Sufficient hand supination to expose tendon Longitudinal/Coronal Probe Slightly distal from Radial Head Lateral becomes top of image Bic Ten Deep Orientation of image can be difficult due to a 90 ⁰ rotation of the anatomy on the ultrasound monitor. Lateral Approach Injection Setup Extensors Supinator Medial Approach Bic Ten Probe Position and Needle Advancement The probe is in short axis /coronal orientation along the lateral elbow compartment. The needle is advanced in plane with the radius and tendon well visualized. 3
Medial Approach to the Through the Pronator window FCU Bic Ten Pronator Dorsal Approach Unchanged patient position. Medial to lateral beam angle Probe at radial tuberosity Hyperechoic fibers seen from left side of image. Dorsal Approach to the Dorsal Approach Distal Biceps : Supination The most direct approach to view the attachment and perform guided injection. Biceps attachment on Radial Tuberosity NOT visible with supinated arm in 90⁰ flexion Dorsal Approach Distal Biceps : Pronation Dorsal Approach Distal Biceps : Dynamic Image Pronation of arm exposes the tendon attachment on Radial tuberosity 4
Anterior Lateral Longitudinal Anterior Joint space and Annular Ligament (Not the lateral epicondyle view.) Lateral Elbow Annular Lig H RH LAX Probe Lateral margin of Antecubital Fossa Anechoic hyaline cartilage lines Humerus (H) and the Radial Head (RH) Annular ligament contours Radial head Anterior joint is V shaped Synovial fringe extends from synovial membrane. Lateral Epicondyle Longitudinal Common Extensor Tendon and Radial Collateral Ligament Fig. 1 Radial Nerve Cutaneous Sensory and Posterior Inter-osseous branches BrRad Br LAX Probe Span the joint space Visualize the Epicondyle! Hyperechoic Common Extensor is fibrillar & superficial to the darker/hypoechoic RCL SAX Probe At the joint space The hyperechoic RADIAL NERVE is identified between the Brachioradialis and the Radial Nerve The Cutaneous Sensory and Posterior Interosseous (PIN) The Cutaneous Sensory and Posterior Interosseous ( PIN ) BrRad Br Slight Distal/Lateral Probe Translation from RN RH Radial Head becomes the only boney landmark. The PIN splits laterally The Cutaneous Sensory nerve splits medially Both are HYPOECHOIC due to anisotropy 5
Posterior Interosseous ( PIN ) s1 s2 Medial Elbow RH Meticulous Distal Probe Translation along radial margin remains the only boney landmark. The PIN is quite small and found between the superficial (s1) and deep (s2) heads of the Supinator muscle Medial Epicondyle: Common Forearm Flexor and r Collateral Ligament Medial Epicondyle MED EPI ULNA Supine patient external rotation Probe Anterior to Epicondyle Dynamic UCL Evaluation Valgus stress by depressing the wrist Normal = < 2mm Abnormal = > 2mm Posterior Midline Longitudinal Posterior Elbow Landmarks are Humeral Trochlea. and distal r Olecranon. Hyperechoic tendon fibers superficial to deeper Triceps muscle.. Med Tr Olec Process HUM 6
Posterior Midline Transverse r Nerve Short Axis Triceps muscle seen in x-section Deep concavity is Olecranon Fossa SAX probe proximal to Olecranon Tri Muscle SAX Tri Ten LAT Tri Muscle Fat & Synovium Tri Ten Capsule MED Probe position is SAX Bridging the r groove. Black Star = Olecranon process Red Star = Medial Epicondyle Hum Hum r Nerve Short Axis r Nerve Dynamic Imaging Subluxing Nerve MT Med Epi Olec Probe position is SAX Bridging the r groove. The Sub-Q nerve is typically a hypoechoic oval starry night internal echoes adjacent to medial epicondyle Adjacent Muscle: Medial Triceps (MT) The hypo echoic r nerve will slide up and over the adjacent Medial Epicondyle r Nerve X-sectional Area r Nerve Imaging : Longitudinal Proximal to the nerve entering Cubital Tunnel Radial Aspect r Nerve Med Epi r Groove Accepted abnormal x-sectional value is > 10 mm² proximal to the groove. Some variability based on individual patient BMI. Contralateral imaging recommended Probe position on posterior aspect of humerus in LAX r nerve dips between the Flexor Carpi ris, and Flexor Digitorum Profundus as it goes distally. Typically, NOT as efficient as SAX image. 7
Pre-stenotic dilatation of ulnar nerve using LAX Thank You! 8