title: Metatarsophalangeal joint pathology in crossover second toe deformity: a cadaveric study.
abstract: BACKGROUND
  Ligamentous and capsular insufficiency of the second metatarsophalangeal joint has been surgically treated for over two decades, mainly with indirect surgical repairs, which stabilize adjacent soft tissue and shorten or decompress the osseous structures. While ligamentous insufficiency has been described and recognized, degeneration of the plantar plate and tears of the capsule have rarely been documented. The purpose of this study was to document and describe the presence and pattern of plantar plate tears in specimens with crossover second toe deformities, and based on this, to develop an anatomical grading system to assist in the assessment and treatment of this condition.
  
  
  METHODS
  Sixteen below-knee cadaveric specimens with a clinical diagnosis of a second crossover toe deformity were examined, and dissected by removing the metatarsal head. The pathologic findings of plantar plate and capsular pathology, as well as ligamentous disruption, were observed and recorded. Demographics of the specimens were recorded, and simulated weightbearing radiographs were obtained prior to dissection so that pertinent angular measurements could be obtained.
  
  
  RESULTS
  Demographics demonstrated a high percentage of female specimens, and a typically older population that has been reported for this condition. Radiographic findings documented a high percentage of hallux valgus and hallux rigidus deformities. The MTP-2 and MTP-3 angles were divergent consistent with a crossover toe deformity. We consistently found transverse tears in the plantar plate region immediately proximal to the capsular insertion on the base of the proximal phalanx. With increasing deformity, wider distal transverse tears extending from lateral to medial were found. Midsubstance tears, collateral ligament tears, and complete disruption of the plantar plate were found in more severe deformities.
  
  
  CONCLUSIONS
  In this largest series of cadaveric dissections of crossover second toe deformities, we describe the types and extent of plantar plate tears associated with increasing deformity of the second ray. We present, based on these findings, an anatomic grading system to describe the progressive anatomic changes in the plantar plate.
authors.affiliation: Coughlin Clinic at Saint Alphonsus Medical Center, Boise, ID 83706, USA. footmd@aol.com
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Coughlin
authors.forename: Shane A
authors.initials: SA
authors.lastname: Schutt
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Hirose
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Kennedy
authors.forename: Brett R
authors.initials: BR
authors.lastname: Grebing
authors.forename: Bertil W
authors.initials: BW
authors.lastname: Smith
authors.forename: M Truitt
authors.initials: MT
authors.lastname: Cooper
authors.forename: Pau
authors.initials: P
authors.lastname: Golano
authors.forename: Ramón
authors.initials: R
authors.lastname: Viladot
authors.forename: Fernando
authors.initials: F
authors.lastname: Alvarez
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D005260:Female; D005530:Foot Deformities / Q000473:pathology*; D006801:Humans; D008023:Ligaments, Articular / Q000473:pathology; D008297:Male; D008683:Metatarsophalangeal Joint / Q000473:pathology*