US of Elbow, Wrist, and Hand Disclosures: Pathology with MRI Correlation • Consultant: Bioclinica • Book Royalties: Elsevier Jon A. Jacobson, M.D. • Advisory Panel: GE, Philips Professor of Radiology Director, Division of Musculoskeletal Radiology University of Michigan Note: all images from the textbook Fundamentals of Musculoskeletal Ultrasound are copyrighted by Elsevier Inc. Outline: elbow Biceps Brachii: • Insertion: radial tuberosity • Biceps tendon – Short head: superficial, distal • Epicondylitis – Long head; deep, proximal • Ulnar collateral ligament • No synovial sheath • Cubital tunnel • Bicipitoradial bursa From: Eames M. et.al. J Bone Joint Surg 2007:89:1044 Biceps Brachii Tendon: distal Biceps Brachii: terminal bifurcation A Short A head Brachialis Brachialis Trochlea Transverse Long Lateral Transverse Medial Lateral Medial head Radial Tuberosity Note: toggling the transducer, which creates anisotropy allows visualization Long Axis of two tendon heads 1 = long head Tagliafico A., et.al. Eur Radiol 2010 Courtesy of M. Chiavaras, Hamilton, Ontario 2 = short head 1 Biceps Brachii Tendon: tendinosis Tendon Abnormalities: • Tendinosis: hypoechoic, swollen • Partial-thickness tear: anechoic focus, Radius Ulna no retraction Medial Approach • Full-thickness tear: discontinuity Dorsal Position – Dynamic imaging: retraction Biceps Brachii Tendon: complete tear Biceps Tendon: non-retracted complete tear Proximal biceps stump Long Axis Distal biceps stump Radial Radial Tuberosity Head Longitudinal Transverse Normal Biceps Brachii Tendon: Biceps Brachii: short head tear complete tear non-retracted Yellow arrows = short head Longitudinal: dynamic imaging White arrows = fluid around long head Kalume Brigido M. Eur Radiol 2009 ; 19:1817 2 Biceps Brachii: short head tear Biceps Yellow arrows = Brachii: tear of short short head head tear White arrows = intact long head Yellow arrows = tear of short head White arrows = intact long head Biceps Tendon Tears: dynamic imaging Outline: elbow • Biceps tendon • Epicondylitis • Ulnar collateral ligament • Cubital tunnel Partial Tear Complete Tear Lateral Collateral Ligament Complex Lateral Collateral E Ligament Complex Note: footprints • Common extensor tendon (curved arrows) • Radial collateral ligament • Radial collateral ligament (arrows) (arrowheads) • Common extensor tendon (E) • Annular ligament (a) • Annular ligament (arrowhead) • Lateral ulnar collateral ligament Jacobson J. et al. (curved arrow) J Ultrasound Medicine Jacobson J. et al. J Ultrasound Medicine 2013 (in print) 2013 (in print) Common Extensor Tendon Removed 3 Epicondylitis: Common Extensor Tendon: elbow • Common flexor and extensor tendons • Often called “tennis elbow” or “lateral • Abnormal hypoechogenicity epicondylitis” or “epicondylosis” or …… • All terms are misnomers – Mucoid degeneration, tendinosis • Those inflicted usually do not play tennis • Anechoic: partial-thickness tear (professionally or correctly) • No inflammatory cells* • It is not inflammatory • It is not a primary problem of the epicondyle Potter, Radiology 1995; 196:43 Connell, AJR 2001; 176:777 Common Extensor Tendon: epicondylitis Common Extensor Tendon: epicondylitis Long Axis Short Axis Lateral Radial Epicondyle Head Patient #1 Patient #2 Note: normal radial collateral ligament (white arrow) Outline: elbow Collateral Ligament Tear • Biceps tendon • Partial tear: hypoechoic, thickened • Epicondylitis • Complete tear: anechoic fluid tracking through ligament defect • Ulnar collateral ligament • Dynamic examination: stress • Cubital tunnel Miller et al. Skeletal Radiol 2004; 33:386 4 Ulnar Collateral Ligament: complete tear Ulnar Collateral Ligament: partial tear Med Epic Ulna Longitudinal Coronal T2w Normal Ulnar Collateral Ligament: partial tear Ulnar Collateral Ligament • Valgus stress: 30 degrees elbow flexion – Unlock the olecranon – Stress the UCL anterior band • Gravity stress is adequate, equal to Telos1 • Ultrasound measurements: – Reliable and precise2 1Harada M et al. J Sho Elb Surg 2014; 23:561 2Bica D et al. J Ultrasound Med 2015; 34:371 Ulnar Collateral Ligament: laxity Ulnar Collateral Ligament: valgus stress • >1 mm asymmetric gapping = 87% accuracy in diagnosis of UCL tear – MR arthrography accuracy = 88% – US + MR arthrography: accuracy = 98% • Asymmetric joint space widening with stress: – Normal: 1.3 mm or less – Partial tear: 1.2 – 3.0 mm – Full thickness tear: 2.8 – 4.8 mm With valgus stress Roedl JB et al. Radiology 2016 T2w fat sat 5 Ulnar Nerve: anatomy Outline: elbow • Behind medial epicondyle Ulnar Nerve • Biceps tendon of humerus: Osborn’s fascia – Cubital tunnel retinaculum or Arcuate ligament • Epicondylitis Osborn’s fascia • Distal to epicondyle: • Ulnar collateral ligament – True cubital tunnel – Between ulnar and humeral • Cubital tunnel heads: flexor carpi ulnaris – Under arcuate ligament Martinoli, C. et al. Radiographics 2000;20:S199-S217 Cubital Tunnel Syndrome Ulnar Nerve: cubital tunnel syndrome Arcuate Ligament • Enlarged1 >9.5 mm2 • Hypoechoic • Causes: – Idiopathic, overuse – Joint process, intra-articular body – Anconeus epitrochlearis: • Normal variant accessory muscle 1Thoirs, J Ultrasound Med 2008; 27:737 Isolated Ulnar Nerve Dislocation Snapping Triceps Syndrome: dynamic imaging Ulnar Nerve Anterior Posterior Medial Epicondyle Apex Short Axis Transverse 6 de Quervain Tenosynovitis: Outline: wrist and hand • Stenosing tenosynovitis – Overuse, primary care givers • Tendon abnormalities • 1st dorsal wrist compartment: • Carpal tunnel syndrome – Extensor pollicis brevis + abductor pollicis longus • Gamekeeper’s thumb • Ultrasound findings: – Thick synovial sheath – Tendinosis – Cortical irregularity, hyperemia J Ultrasound Med 1997; 16:685 De Quervain’s Tenosynovitis De Quervain’s Tenosynovitis AbPL EPB EPB AbPL Radius EPB Radius Long Axis Short Axis Axial PDw Axial T2w Short Axis Long Axis Pitfall Alert! Pseudo-tendon Tear Pitfall Alert! Pseud-tendon tear • Multiple tendon fascicles • Abductor pollicis longus • Extensor carpi ulnaris – Incidence: 80% • 6th extensor compartment – Up to 4 fascicles • Short axis: hypoechoic cleft • Extensor pollicis brevis • Due to fibrovascular tissue Ulna – Incidence: 7% in between two heads of extensor carpi ulnaris – Up to 2 fascicles Short Axis – May be absent • “Lotus Root Sign” – Seen best distal to radius Rousset et al. Radiology 2010; 257:427 Choi et al. Radiology 2011; 260:480 7 Carpal Tunnel Syndrome: Outline: wrist and hand • Proximal median nerve swelling – Area: circumferential trace • Tendon abnormalities – Normal: <9 mm2 • Carpal tunnel syndrome – Borderline: 9 – 12 mm2 2 • Gamekeeper’s thumb – Abnormal: > 12 mm • 12.8 mm2 = moderate (83% sens, 95% spec) • 14.0 mm2 = severe (77% sens, 100% spec) Klauser AS et al. Sem Musculoskel Rad 2010; 14:487 Ooi et al. Skeletal Radiol 2014; 43:1387 Carpal Tunnel Syndrome “Notch Sign” Carpal Tunnel Syndrome • Compare areas: – Proximal: pronator quadratus PQ – Distal: carpal tunnel Rad 9 mm2 Radius • ≥ 2 mm2 = carpal tunnel Lunate Capitate syndrome • 99% sensitivity • 100% specificity 2 Klauser AS. Radiology 2009; 250:171 21 mm Bifid Median Nerve + CTS Carpal Tunnel Syndrome: proximal • Carpal tunnel syndrome • Change in cross- sectional area of ≥ 4 mm2 • Proximal: pronator quadratus • Distal: at carpal tunnel Short Axis Axial T2w Klauser et al. Radiology 2011; Short Axis Normal 259; 808 8 Gamekeeper’s Thumb • Injury of the ulnar collateral ligament (UCL) of the thumb Outline: wrist and hand – Historically, chronic injury in Scottish gamekeepers – Frequently, due to acute MCP joint hyperabduction • Tendon abnormalities – Skier’s thumb: up to 86% of thumb base injuries • Carpal tunnel syndrome • Gamekeeper’s thumb Rabbit Mandals Acute Mechanism Chronic Mechanism Ulnar Collateral Ligament: thumb Ulnar Collateral Ligament: thumb MC PP Note: sliding of adductor aponeurosis with isolated NormalSprain Partial Nondisplaced Displaced interphalangeal joint flexion Tear Complete Complete Tear Tear (Stener Lesion) (+ fracture) Radiographics 2006;26:1007 UCL: tears Stener Lesion: • Displaced proximal stump of torn UCL – Hypoechoic & round – Proximal to MCP joint – At proximal edge of adductor aponeurosis Partial-thickness tear Full-thickness tear • No tissue spanning MCP joint • “Yo-yo on a string” sign • Ultrasound: 100% accuracy *Melville D. et al. Skeletal Radiology 2013; 42:667 Normal 9 Stener Lesion: variations Stener Lesion: dynamic Normal 12 1st Metacarpal Proximal Non-displaced tear 34 Phalanx White arrows = adductor aponeurosis Yellow arrows = Stener lesion Displaced Full-thickness Tears Normal Stener Lesion Stener Lesion Long Axis Long Axis Normal Normal From: Melville D. et al. Skeletal Radiology 2013; 42:667 From: Melville D. et al. Skeletal Radiology 2013; 42:667 Take-home points: • Biceps: terminal bifurcation • Epicondylitis: misnomer • De Quervain: lotus root sign • Carpal tunnel syndrome: change in area • Dynamic imaging: – Biceps, UCL elbow, ulnar nerve, Stener See www.jacobsonmskus.com for syllabus and other educational material 10.