细微舟状骨骨折的影像学诊断

Heeren Makanji, 2011 Gillian Lieberman, MD August 2011 Heeren Makanji, Harvard Medical School Year III Gillian Lieberman, MD Our Patient #1: History and Physical Exam Heeren Makanji, 2011 Gillian Lieberman, MD • 36 yo with FOOSH 3 months ago • Persistent pain in radial side of left wrist, worse with movement • Anatomic snuffbox tenderness http://www.picturesof.net/pages/110102- 144849-942053.html Heeren Makanji, 2011 Gillian Lieberman, MD Our Patient #1: Differential Diagnosis • Fracture (scaphoid, triquetrum, lunate, distal radius) • Ligament or Tendon Injury • Dislocation • Osteoarthritis • Infection • Nerve impingement Heeren Makanji, 2011 Gillian Lieberman, MD Our Patient #1: Plain Films PA View Oblique View PACS, BIDMC PACS, BIDMC Findings: Linear lucency in scaphoid waist with surrounding sclerosis Heeren Makanji, 2011 Gillian Lieberman, MD PACS, BIDMC Our Patient #1: MRI Findings: •Fracture line through scaphoid waist • Bone marrow edema • Cystic areas in the bones T2-weighted MRI CONSIDER: WAS THIS MRI INDICATED? Our Patient #2: History and Physical Exam • 27 yo, fells horizontally on right wrist and forearm • Persistent pain in radial side, swelling • Anatomic snuffbox tenderness FOOSH Heeren Makanji, 2011 Gillian Lieberman, MD http://singlemindedwomen.com/blog/sex-the-single- woman-falling-for-you/attachment/tripping/ Heeren Makanji, 2011 Gillian Lieberman, MD Our Patient #2: Plain Films PACS, BIDMC PA View PACS, BIDMC Scaphoid View Findings: Soft tissue/bone artifact, no evidence of fracture Heeren Makanji, 2011 Gillian Lieberman, MD Our Patient #2: Interval History • Wrist immobilization with cast • Scheduled for repeat radiographs 2 weeks later • Pain persisted, still worse with movement • Continued anatomic snuffbox tenderness Heeren Makanji, 2011 Gillian Lieberman, MD Our Patient #2: Plain Films, 1 Month Later PACS, BIDMC Oblique View Findings: •Linear lucency reflecting scaphoid fracture or soft tissue density Heeren Makanji, 2011 Gillian Lieberman, MD Our Patient #2: MRI PACS, BIDMC T2-weighted MRI Findings: • Fracture line through scaphoid waist/distal pole boundary • Bone marrow edema in distal pole CONSIDER: WAS THIS MRI INDICATED? Heeren Makanji, 2011 Gillian Lieberman, MD Objectives • Regional Anatomy of the Wrist • Menu of Radiological Tests • When to Order Certain Radiological Tests Heeren Makanji, 2011 Gillian Lieberman, MD Scaphoid Fractures: The Basics • Accounts for 79% of carpal fractures • Mechanism of injury: dorsiflexion and radial deviation • Young and healthy population • 70% in waist, 20% in proximal pole, 10% in distal pole • Prognosis improves with more distal fractures Regional Anatomy: Carpal Bones Heeren Makanji, 2011 Gillian Lieberman, MD A H B G F E C D Proximal Row A-Scaphoid B-Lunate C-Triquetrum D-Pisiform Distal Row E-Trapezium F-Trapezoid G-Capitate H-Hamate Temple, CL, et al., J Hand Surg, 2005 May; 30(3): 534-542. Regional Anatomy: Blood Supply to the Scaphoid Heeren Makanji, 2011 Gillian Lieberman, MD Blood is supplied from the distal to proximal pole, making the proximal pole susceptible to AVN in scaphoid fractures Amadio PC, et al. Green’s operative hand surgery, 5th edition. 2005. pp. 711–768 Heeren Makanji, 2011 Gillian Lieberman, MD Menu of Radiological Tests • Plain films • Ultrasound • Bone scan • CT • MRI Heeren Makanji, 2011 Gillian Lieberman, MD Menu of Radiological Tests: Plain Films • 1st diagnostic step • Use specialized views to visualize scaphoid • Misses up to 20% of scaphoid fractures • Low inter- and intra- observer reliability in multiple studies • Bone and soft tissue artifacts possible Smith M, et al., ANZ J. Surg, 2010 Jan;80(1-2): 82-90. Menu of Radiological Tests: Scaphoid Views Heeren Makanji, 2011 Gillian Lieberman, MD PACS, BIDMC PACS, BIDMC PACS, BIDMC PACS, BIDMC Neutral PA 30 degrees 45 degrees 60 degrees Beam is angulated toward the elbow; useful for detecting waist fractures Menu of Radiological Tests: Ultrasound Heeren Makanji, 2011 Gillian Lieberman, MD Smith M, et al., ANZ J. Surg, 2010 Jan;80(1-2): 82-90. • High-spatial resolution sonography (5-15 MHz) • Specific, but not sensitive; rarely used in United States Findings: Cortical disruption, hematoma Findings: Cortical disruption, soft tissue swelling, joint effusion Menu of Radiological Tests: Radionuclide Bone Scan Heeren Makanji, 2011 Gillian Lieberman, MD • High sensitivity, low specificity • Age affects rate of osteoblastic activity • Quantification bone scan has higher specificity but rarely used Rhemrev SJ, et al., Int J Emerg Med, 2011 Feb;4:4 Findings: Increased uptake in the right scaphoid Menu of Radiological Tests: CT Scan Heeren Makanji, 2011 Gillian Lieberman, MD • High sensitivity and specificity • Best spatial resolution allows for detection of displacement, angulation, and non-union • Longitudinal axis slices preferred; risk of missing oblique non-unions • Useful for operative planning Companion Patients #1 and #2: CT Scan Heeren Makanji, 2011 Gillian Lieberman, MD PACS, BIDMC Smith M, et al., ANZ J. Surg, 2010 Jan;80(1-2): 82-90 Findings: Scaphoid waist fracture Findings: Displaced scaphoid waist fracture Menu of Radiological Tests: MRI Heeren Makanji, 2011 Gillian Lieberman, MD • Most sensitive and specific imaging test • Useful for evaluating soft tissue injuries and avascular necrosis • Is it cost-effective? PACS, BIDMC T2-weighted MRI Findings: Fracture line, bone marrow edema When to Order Certain Radiological Tests Heeren Makanji, 2011 Gillian Lieberman, MD • Studies showed that imaging protocol varies significantly: In study of 105 hospitals across 6 continents, only 7% of hospitals shared same protocol • Four-view plain radiograph may miss scaphoid fractures; patients may present months to years after initial injury • Balance diagnostic use, cost-effectiveness, patient compliance • ACR recommends use of repeat radiographs or MRI for initially undetected fractures • In prospective study, use of early MRI, before repeat radiographs, resulted in therapeutic consequence in 66% of cases • Cost-effectiveness studies have been equivocal When to Order Certain Radiological Tests: Algorithm Heeren Makanji, 2011 Gillian Lieberman, MD Concern for Complications/Displacement? Treatment Fracture detected Initial Radiographs Show Fracture? Yes YesNo Which Complication? OA (Plain Film) SLAC (Plain Film) AVN (MRI) Non-Union (CT or MRI) No Casting and repeat radiographs in 10-14 days Or MRI Refer to Concern for Complications/ Displacement Displacement (CT) No fracture detected and persistent symptoms Repeat MRI Or CT Back to Our Patients #1 and #2 Heeren Makanji, 2011 Gillian Lieberman, MD Patient #1: Injury 3 months prior, evidence of non-union on plain films MRI indicated? Patient #2: Initial plain radiographs normal, follow-up radiographs were inconclusive MRI indicated? YES YES Summary Heeren Makanji, 2011 Gillian Lieberman, MD • Scaphoid fractures are most common carpal fracture • Menu of radiological tests include plain films, ultrasound, bone scan, CT, and MRI • Four-view plain films, including scaphoid view, is initial radiological test • MRI has highest sensitivity and specificity for detecting scaphoid fractures • CT useful for assessing displacement and for operative planning Acknowledgements Heeren Makanji, 2011 Gillian Lieberman, MD Dr. Mary Hochman Dr. Gillian Lieberman Emily Hanson References Heeren Makanji, 2011 Gillian Lieberman, MD Amadio PC, Moran SL. Fractures of carpal bones. In: Green DP, Pederson WC, Hotchkiss RN, Wolfe SW, editors. Green’s operative hand surgery. 5. Philadelphia: Elsevier; 2005. pp. 711–768. Dorsay TA, Major NM, Helms CA. Cost-effectiveness of immediate MR imaging versus traditional follow-up for revealing radiographically occult scaphoid fractures. AJR Am J Roentgenology. 2001 Dec;177:1257-63 Duckworth AD, Ring D, McQueen MM. Assessment of the suspected fracture of the scaphoid. J Bone Joint Surg Br. 2011 Jun;93(6): 713-9 Gelberman RH, Menon J. The vascularity of the scaphoid bone. J Hand Surg.1980 Feb;5: 508-13 Groves AM, Kayani I, Syed R, Hutton BF, Bearcroft PP, Dixon AK, et al. An international survey of hospital practice in the imaging of acute scaphoid trauma. AJR Am J Roentgenology. 2006 Dec;187(6): 1453-6 Kozin SH. Incidence, mechanism, and natural history of scaphoid fractures. Hand Clin. 2001 Nov;17(4): 515-524 Mack MG, Keim S, Balzer JO, Schwarz W, Hochmuth K, Windolf J, et al. Clinical impact of MRI in acute wrist fractures. Eur Radiol. 2003 Mar;13(3): 612-7 Rhemrey SJ, Ootes D, Beeres FJ, Meylaerts SA, Schipper IB. Current methods of diagnosis and treatment of scaphoid fractures. Int J Emerg Med. 2011 Feb;4:4 Ring D, Jupiter JB, Herndon JH. Acute fractures of the scaphoid. J Am Acad Orthop Surg. 2000 Jul-Aug;8(4): 225-31 Rubin DA, Dalinka RH. Expert Panel on Musculoskeletal Imaging. Acute Hand and Wrist Trauma [online publication]. Reston, Virginia: American College of Radiology (ACR), 2005;8. References Heeren Makanji, 2011 Gillian Lieberman, MD Smith M, Bain GI, Turner PC, Watts AC. Review of imaging of scaphoid fractures. ANZ J Surg. 2010 Jan;80(1-2): 82- 90 Strauch, RJ. Scapholunate advanced collapse and scaphoid nonunion advanced collapse arthritis-update on evaluation and treatment. J Hand Surg Am. 2011 Apr;36(4): 729-35 Temple CL, Ross DC, Bennett JD, Garvin GJ, King GJ, Faber KJ. Comparison of sagittal computed tomography and plain film radiography in a scaphoid fracture model. J Hand Surg Am. 2005 May;30(3): 534-42 Vrettos BC, Adams BK, Knottenbelt JD, Lee A. Is there a place for radionuclide bone scintography in the management of radiograph-negative scaphoid trauma? S. Afr Med J. 1996 May;86(5): 540-2 Wheeless, CR. Wheeless’ Textbook of Orthopaedics. 2011. http://www.wheelessonline.com/. 17 Aug 2011