• BACKGROUND
    • The aim of this study was to evaluate the incidence and morphologic characteristics of osteochondral lesions of the distal tibial plafond (OLTP) by location and morphologic characteristics on MRI.
  • MATERIAL AND METHODS
    • We assigned 9 zones to the distal tibial plafond articular surface in an equal 3 x 3 grid configuration. Zone 1 was the most anterior and medial, zone 3 was anterior and lateral, zone 7 was most posterior and medial, and zone 9 was the most posterior and lateral. The grid was designed with all 9 zones being equal in surface area. Two observers reviewed MRI examinations of 38 patients (12 males and 26 females; mean age, 38.7 years; age range, 10 to 68 years) with reported OLTPs. We recorded the frequency of involvement and size of lesion for each zone. A chart review was performed.
  • RESULTS
    • Of the 38 OLTP found in this study, 14 (37%) of the lesions were on the medial tibial plafond [zones 1, 4 and 7] and 11 (29%) involved the lateral tibial plafond [zones 3, 6 and 9]; 13 lesions (34%) localized to the center third of the plafond [zones 2, 5 and 8]. Nine of the lesions (24%) were on the anterior tibial plafond [zones 1, 2 and 3], 15 lesions (39%) predominately involved the posterior plafond [zones 7, 8 and 9], and 14 lesions (37%) localized to the central third of the plafond [zones 4, 5 and 6]. The medial central tibial plafond was most frequently involved site with 8 of the 38 (21%) lesions located there; the posterior medial tibial plafond was second most frequently involved with six of the 38 lesions (16%). Six of 38 ankles had both a talar osteochondral lesion and an OLTP. Of these, only one was a ;kissing' lesion. Chart review revealed that all subjects had ankle pain at time of MRI examination.
  • CONCLUSION
    • We conclude that osteochondral lesions of the distal tibial plafond must be considered in the differential diagnosis of patients with symptomatic ankles and that no location had a significantly higher incidence.