Rockwood, Green, and Wilkins' Fractures, 10e Package

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CHAPTER 5 • Classification of Fracture

MRI of Pelvic Fractures and Posterior Ligaments Kenawey reported on the use of MRI in addition to CT imag ing in the evaluation of eight children with “displaced pelvic fractures, Tile C, and open triradiate cartilage.” Kenawey noted that the anterior sacroiliac ligaments were disrupted in all cases while the pelvic floor ligaments were disrupted in five of eight patients. 28 Gary et al. reported the results of using MRI for the evalu ation of ligamentous injury with pelvic ring injuries in a pro spective case-controlled study. 18 They noted that tearing of the sacrospinous ligament is variable among anteroposterior compression (APC) type II injuries and noted that this injury pattern can be subdivided into those with and without sacro spinous ligament tears. 18 These authors also noted that other than the exception of the APC-II injuries, that their findings of ligament injury and pelvic injury type “generally agreed with the Young–Burgess classification system.” 18 MRI of Knee Fracture Dislocations Obviously, MRI could be described as a standard of care with regard to traumatic injuries to the knee, especially in the setting of negative radiographs. However, recent authors have investi gated the use of MRI with tibial plateau fractures to assess the integrity of the numerous ligamentous structures necessary for knee stability. Stannard et al. reported high rates of soft tissue injury with all types of tibial plateau fractures and that 53% of these patients had multiple ligaments damaged. 59 Voss et al. compared MRI and CT for fracture classification and detection of soft tissue injury with tibial plateau fractures and surveyed OTA and AO. These authors reported that survey respondents identified the correct Schatzker fracture type with MRI 73.5% of the time compared to 58.1% of the time using CT. In addition, these authors noted that MRI was “favored among survey respondents for preoperative planning, Schatzker classification, and surgical approach.” 64 Some authors have noted a specific application of MRI imag ing of Schatzker type IV tibial plateau fractures. 66,68 Zhang et al. studied 49 Schatzker type IV using MRI and CT. 68 They reported that incidence of associated soft tissue injuries as 96.7% for ante rior cruciate ligament (ACL) tears, 43.3% for posterior cruciate ligament (PCL) tears, and 70% for medial collateral ligament (MCL) tears. 68 Yan et al. studied 27 patients with Schatzker IV injuries and reported the prevalence of soft tissue injuries from operative notes and MRI data. 66 They reported the incidence of lateral meniscus tears and medial meniscus tears was 63% and 44.4%, respectively; and the incidence of ACL tears and PCL tears was 92.6% and 70.4%, respectively. 66 These findings have initiated further soft tissue, specifically ligamentous attention, for trauma surgeons managing tibial plateau fractures. None of these MRI study findings are surprising. A Schatzker IV fracture is generally thought of as fracture-dislocation of the knee. In summary, as technology advances, so does our under standing of the traumatic injuries we treat. Radiographs could be described as the single most important technologic advance ment of musculoskeletal treatment; however, CT and MRI

TABLE 5-3. Accepted OTA/OA Fracture

Classification Universal Modifiers

1. Nondisplaced 2. Displaced 3. Impaction 3a: Articular 3b: Metaphyseal 4. No impaction 5. Dislocation 5a: Anterior (volar, palmar, plantar) 5b: Posterior (dorsal) 5c: Medial (ulnar) 5d: Lateral (radial) 5e: Inferior (with hip is also obturator) 5f: Multidirectional 6. Subluxation/ligamentous instability 6a: Anterior (volar, palmar, plantar) 6b: Posterior (dorsal)

severity from 0 to 3. 42 This system has not been widely utilized, and there has been a paucity of literature reviewing the reli ability of this system, with most studies demonstrating only a moderate degree of reliability. 63 There is no question that improved classification of the inju ries to the soft tissue envelope surrounding fractures is import ant for treatment, prognosis, and outcome. Further work in this area is clearly needed–for example, how do traditional classifi cation schemes based on radiographic imaging predict injuries to surrounding ligamentous structures, in the ankle, pelvis, or knee? Is this information consistent with what can be directly observed with advancements in our imaging technology? Only time will tell, but several preliminary studies indicate that information gained can have a clear influence on our historic understanding of the pathoanatomic etiologies and ultimate interventions in fracture care. 15,59,65 6c: Medial (ulnar) 6d: Lateral (radial) 6e: Inferior (with hip is also obturator) 6f: Multidirectional 7. Diaphyseal extension 8. Articular cartilage injury a 8a: ICRS Grade 0: Normal 8b: ICRS Grade 1: Superficial indentation (A) and/or superficial fissures and cracks (B) 8c: ICRS Grade 2: Abnormal lesions extending down to 50% of cartilage depth 8d: ICRS Grade 3: (A) Severely abnormal with defects extending down >50% of cartilage depth; (B) down to calcified layer; (C) down to subchondral bone but not through; (D) blisters included 8e: ICRS Grade 4: Severely abnormal cartilage loss through sub chondral bone 9. Poor bone quality 10. Replantation 11. Amputation associated with a fracture 12. Associated with a nonarthroplasty implant 13. Spiral-type fracture 14. Bending-type fracture a International Cartilage Repair Society score/grade: ICRS Clinical Cartilage Injury Evaluation System. http://cartilage.org/society/publications/icrs-score/