lisfranc损伤的影像学表现

Imaging of Lisfranc Injury Greg Cvetanovich, Harvard Medical School Year IV Gillian Lieberman, MD November 2011 Greg Cvetanovich, MS4 Gillian Lieberman, MD 2 Agenda • Case Presentation • Introduction • Anatomy • Lisfranc Injury • Classification • Imaging • Treatment Greg Cvetanovich, MS4 Gillian Lieberman, MD 3 Case Presentation • 72M with Parkinson’s disease presents with R foot injury, sustained while walking – Severe pain, swelling, and inability to bear weight – Exquisite tenderness to palpation over 2nd tarsometatarsal joint, somewhat less tender over remaining tarsometatarsal joints – Plantar ecchymosis – Neurovascularly intact distally – No evidence of compartment syndrome Greg Cvetanovich, MS4 Gillian Lieberman, MD 4 Radiograph - Standing AP of bilateral feet - Left: - No acute fracture or dislocation - Right: - Widening between 1st and 2nd metatarsal bases - Loss of normal colinearity of medial border of 2nd metatarsal with medial border of middle cuneiform - “Fleck” fractures around base of second metatarsal - Fractures of bases of first, second, and third metatarsals, medial and middle cuneiforms, and navicular, with intra-articular extension Æ Lisfranc Injury Greg Cvetanovich, MS4 Gillian Lieberman, MD BIDMC PACS 5 Jacques Lisfranc • Jacques Lisfranc de St. Martin (1790-1847) – French surgeon and gynecologist – While serving in Napoleon’s army, described an injury to the tarsometatarsal (TMT) joint in a soldier who fell from a horse with his foot caught in the stirrup – This unfortunate soldier sustained a vascular injury as well and underwent partial amputation of the foot at the TMT joint, which Lisfranc reportedly performed in under 1 minute • “Lisfranc” eponym is currently applied to various structures of and injuries to the TMT joint complex Greg Cvetanovich, MS4 Gillian Lieberman, MD Lisfranc http://www.whonamedit.com/doctor.cfm/2572.html; http://en.wikipedia.org/wiki/File:Jacques_Lisfranc.jpg 6 Anatomy: Lisfranc Joint Complex Greg Cvetanovich, MS4 Gillian Lieberman, MD Hatem SF. Radiol Clin N Am, 2008; Watson TS, et al. JAAOS, 2010; Thompson MC, et al. JAAOS, 2003 Ligamentous Stability Osseous Stability 7 Introduction: Lisfranc Injuries • Range from mild sprains to severe dislocations – Associated with tarsal and metatarsal fractures • ~0.2% of all fractures • 20% are missed/misdiagnosed initially – Especially in polytraumatized patients • Mechanism: – 2/3 are high energy (MVA, fall from height, industrial accident) – 1/3 are low energy (~4% of American football players per season) – Twisting, axial loading, and/or crushing • High index of suspicion necessary – Goal: avoid sequelae of posttraumatic arthritis Greg Cvetanovich, MS4 Gillian Lieberman, MD Lisfranc Watson TS, et al. JAAOS, 2010; http://en.wikipedia.org/wiki/File:Jacques_Lisfranc.jpg 8 Clinical Evaluation: Lisfranc Injuries • Pain, midfoot swelling, variable deformity • Unable to bear weight • Plantar ecchymosis is pathognomonic – Plantar ecchymosis sign • Diastasis between 1st and 2nd metatarsals – Gap sign • Tender to palpation over dorsal TMT joints • Stress testing for pain +/- midfoot instability • Carful neurovascular exam is key – Dorsalis pedis artery passes between 1st and 2nd metatarsals, in danger during injury or treatment – Compartment syndrome is common, especially with high energy mechanisms Greg Cvetanovich, MS4 Gillian Lieberman, MD Watson TS, et al. JAAOS, 2010; Thompson MC, et al. JAAOS, 2003 www.orthofootankle.com/tag/lisfranc-injury/; www.emedicine.medscape.com 9 * Radiographic Evaluation: Lisfranc Injuries • AP Radiographs – Loss of normal colinearity of medial border of second metatarsal with medial border of middle cuneiform – Diastasis between first and second metatarsals >2.7mm (*) – Small bony fragments (“fleck sign” *) at base of second metatarsal or medial cuneiform, avulsed by disrupted Lisfranc ligament Greg Cvetanovich, MS4 Gillian Lieberman, MD Hatem SF. Radiol Clin N Am, 2008; BIDMC PACS Normal Lisfranc Injury 10 Radiographic Evaluation: Lisfranc Injuries • Oblique Radiographs – Loss of normal alignment of 2nd-4th TMT joints Greg Cvetanovich, MS4 Gillian Lieberman, MD Hatem SF. Radiol Clin N Am, 2008; BIDMC PACS Normal Lisfranc Injury 11 Radiographic Evaluation: Lisfranc Injuries • Lateral Radiographs – Dorsal displacement of the base of 2nd metatarsal – Flattening of the longitudinal arch (not seen here) Greg Cvetanovich, MS4 Gillian Lieberman, MD Hatem SF. Radiol Clin N Am, 2008; BIDMC PACS Normal Lisfranc Injury 12 Radiographic Evaluation: Lisfranc Injuries • If there is clinical suspicion of Lisfranc Injury despite normal non-weight bearing radiographs, can obtain stress views: – Weight-bearing AP radiographs to stress joint complex – AP abduction and pronation stress view is rarely performed • CT – Improves detection and delineation of fractures, including degree of comminution, intra-articular extension, and interposed soft tissues that could impact reduction – Especially useful in high velocity injuries • MRI – Allows direct visualization of integrity of the Lisfranc ligament and surrounding soft tissue structures – Especially useful in low velocity injuries and in the setting of equivocal radiographic studies Greg Cvetanovich, MS4 Gillian Lieberman, MD Hatem SF. Radiol Clin N Am, 2008; Watson TS, et al. JAAOS, 2010 13 CT vs. Plain Radiograph of Same Foot Student Name, year Gillian Lieberman, MD Note the extensive comminution and intra-articular extension which are better seen on CT than plain radiograph BIDMC PACS 14 Example of MRI of Lisfranc Injury Greg Cvetanovich, MS4 Gillian Lieberman, MD Hatem SF. Radiol Clin N Am, 2008; BIDMC PACS Normal Lisfranc ligament in Box (image from Hatem 2008) Lisfranc injury with avulsed base of second metatarsal attached to intact Lisfranc ligament 15 Classification of Lisfranc Injuries • Useful for describing injury and standardizing terminology, but not useful for guiding treatment or prognosis Greg Cvetanovich, MS4 Gillian Lieberman, MD Hatem SF. Radiol Clin N Am, 2008; Watson TS, et al. JAAOS, 2010; http://www2.aofoundation.org/wps/portal/!ut/p/c0/04_SB8K8xLLM9MSSzPy8xBz9CP0os3hng7BARydDRwN39yBTAyMvLwOLUA93I4MQE_2CbEdFAF3RnT4!/?segmen t=Midfoot&bone=Foot&soloState=true&popupStyle=diagnosis&contentUrl=srg/popup/further_reading/PFxM2/80/6103_32_TMTLisfranc_fx_assess.jsp Quenu and Kuss (1909) A) Divergent: metatarsals displaced in sagittal and coronal planes B) Isolated: one or two metatarsals displaced from the others C) Homolateral: all 5 metatarsals displaced in same direction 16 Classification of Lisfranc Injuries • Myerson (1986) classification aims to describe common injury patterns and to attempt to aid in clinical decision making Greg Cvetanovich, MS4 Gillian Lieberman, MD Hatem SF. Radiol Clin N Am, 2008; Watson TS, et al. JAAOS, 2010; 17 Treatment of Lisfranc Injuries • Goals: – Painless, stable foot in good anatomic alignment – Prevent posttramatic sequelae of instability, deformity, and arthritis • Nonoperative management: – Indicated for stable injuries, minimal displacement, and minimal fractures • 1st MT to 2nd MT base diastasis <2mm greater than contralateral side • TMT displacement <2mm greater than contralateral side – Relative contraindications include: Charcot feet, inflammatory arthritis, nonambulatory patient, severe medical comorbidity – Short leg cast or walking boot for 6-10 weeks – Initially non-weightbearing – Repeat weightbearing radiographs at 2 weeks after injury to ensure no osseous displacement or evidence of instability – Progress to weightbearing as tolerated and physical therapy Greg Cvetanovich, MS4 Gillian Lieberman, MD Watson TS, et al. JAAOS, 2010; Thompson MC, et al. JAAOS, 2003 18 Treatment of Lisfranc Injuries • Operative – Indicated for unstable injuries • Displacement of TMT or 1st-2nd MT joints >2mm compared to contralateral – Anatomic reduction and stable fixation is critical to clinical outcome – ORIF with screw fixation – most common – Some use percutaneous K-wires or screws in unstable, nondisplaced injuries – Primary arthrodesis may improve outcomes in primarily ligamentous injury • Post-operative management – Non-weightbearing cast or boot for 6-8 weeks – Full weightbearing around 8 weeks post-operatively – K-wire fixation removed around 6 weeks – Screw fixation removed around 4-6 months, or left indefinitely Greg Cvetanovich, MS4 Gillian Lieberman, MD Watson TS, et al. JAAOS, 2010; Thompson MC, et al. JAAOS, 2003 19 Example: ORIF of Lisfranc Injury Greg Cvetanovich, MS4 Gillian Lieberman, MD BIDMC PACS * Pre-op ORIF Hardware removal Left: pre-op radiograph showing Lisfranc injury Middle: Screw fixation of medial and middle cuneiforms to the second and third metatarsal bases, respectively, reducing and stabilizing this Lisfranc injury Right: Painful hardware has been removed. Post-traumatic TMT arthritis is seen. 20 Take Home Points for Radiologic Diagnosis of Lisfranc Injuries • Commonly missed/misdiagnosed – High index of suspicion necessary – Imaging findings can be subtle • Check for gap between 1st and 2nd MT bases • Check alignment of MTs with associated tarsals • Cannot adequately evaluate lateral TMT joints on an AP film – Must obtain oblique and lateral views • Radiographs significantly underestimate subtle injuries and associated fractures. If high clinical suspicion, consider: – Stress films such as weightbearing (if patient can tolerate) – CT – MRI Greg Cvetanovich, MS4 Gillian Lieberman, MD 21 References • Watson TS, et al. Treatment of Lisfranc Joint Injury: Current Concepts. J Am Acad Orthop Surg 2010;18: 718-728 • Anderson RB, et al. Management of Common Sports-Related Injuries About the Foot and Ankle. J Am Acad Orthop Surg 2010;18: 546-556 • Thompson MC, et al. Injury to the Tarsometatarsal Joint Complex. J Am Acad Orthop Surg 2003;11: 260-267 • Patel A, et al. Midfoot Arthritis. J Am Acad Orthop Surg 2010;18: 417-425 • Hatem SF. Imaging of Lisfranc Injury and Midfoot Sprain. Radiol Clin N Am 2008;46: 1045–1060 • American College of Radiology. ACR Appropriateness Criteria. Acute Trauma to the Foot. 2010 • Rockwood, Green, and Wilkins’ Fractures, 7th Ed. Student Name, year Gillian Lieberman, MD 22 Acknowledgements Jay Patel, MD Iva Petkovska, MD Student Name, year Gillian Lieberman, MD Imaging of Lisfranc Injury Agenda Case Presentation Radiograph Jacques Lisfranc Anatomy: Lisfranc Joint Complex Introduction: Lisfranc Injuries Clinical Evaluation: Lisfranc Injuries Radiographic Evaluation: Lisfranc Injuries Radiographic Evaluation: Lisfranc Injuries Radiographic Evaluation: Lisfranc Injuries Radiographic Evaluation: Lisfranc Injuries CT vs. Plain Radiograph of Same Foot Example of MRI of Lisfranc Injury Classification of Lisfranc Injuries Classification of Lisfranc Injuries Treatment of Lisfranc Injuries Treatment of Lisfranc Injuries Example: ORIF of Lisfranc Injury Take Home Points for Radiologic Diagnosis of Lisfranc Injuries Slide Number 21 Acknowledgements