title: Predictive MRI correlates of lesser metatarsophalangeal joint plantar plate tear.
abstract: OBJECTIVE
  To identify correlated signs on non-enhanced MRI that might improve diagnostic detection of plantar plate (PP) tear.
  
  
  METHODS
  We performed an IRB-approved, HIPAA-compliant retrospective analysis of 100 non-contrast MRI (50 PP tear, 50 controls). All were anonymized, randomized, and reviewed; 20 were duplicated to assess consistency. One musculoskeletal radiologist evaluated qualitative variables. A trained non-physician performed measurements. Consistency and concordance were assessed. Pearson's Chi-square test was used to test the correlation between qualitative findings and PP tear status. Correlation between measurements and PP status was assessed using t tests and Wilcoxon's rank-sum test (p values < 0.05 considered significant). Classification and regression trees were utilized to identify attributes that, taken together, would consistently distinguish PP tear from controls.
  
  
  RESULTS
  Quantitative measurements were highly reproducible (concordance 0.88-0.99). Elevated 2nd MT protrusion, lesser MT supination and rotational divergence of >45° between the 1st-2nd MT axis correlated with PP tear. Pericapsular soft tissue thickening correlated most strongly with PP tear, correctly classifying 95 % of cases and controls. Excluding pericapsular soft tissue thickening, sequential assessment of 2nd toe enthesitis, 2nd flexor tendon subluxation, and splaying of the second and third toes accurately classified PP status in 92 %.
  
  
  CONCLUSIONS
  Pericapsular soft tissue thickening most strongly correlated with PP tear. For cases in which it might be difficult to distinguish pericapsular fibrosis from neuroma, sequential assessment of 2nd toe enthesitis, flexor tendon subluxation and splaying of the 2nd and 3rd toe is most helpful for optimizing accurate diagnosis of PP tear.
authors.affiliation: Cornell University Medical College, New York, NY, USA.
authors.forename: Rachel L
authors.initials: RL
authors.lastname: Umans
authors.affiliation: Harvard University, Cambridge, MA, USA.
authors.forename: Benjamin D
authors.initials: BD
authors.lastname: Umans
authors.affiliation: Albert Einstein College of Medicine, Bronx, NY, USA. hilary.umans@gmail.com.|Lenox Hill Radiology and Imaging Associates, New York, NY, USA. hilary.umans@gmail.com.
authors.forename: Hilary
authors.initials: H
authors.lastname: Umans
authors.affiliation: Albert Einstein College of Medicine, Bronx, NY, USA.|Montefiore Medical Center, Bronx, NY, USA.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Elsinger
mesh_terms: D000328:Adult; D000465:Algorithms; D016022:Case-Control Studies; D003663:Decision Trees; D005260:Female; D018409:Foot Injuries / Q000000981:diagnostic imaging*; D006801:Humans; D007593:Joint Instability; D008279:Magnetic Resonance Imaging; D008297:Male; D008683:Metatarsophalangeal Joint / Q000000981:diagnostic imaging / Q000293:injuries*; D008875:Middle Aged; D000069262:Plantar Plate / Q000000981:diagnostic imaging / Q000293:injuries*; D012189:Retrospective Studies
keywords: MRI; Metatarsalgia; Plantar plate