title: Recurrent dislocation of the patella accompanying hypotrochlea of the femur and malalignment of the patella.
abstract: This case report describes a rare case of recurrent dislocation of the patella which was accompanied with trochlear dysplasia and malalignment of the patella in a 15-year-old girl. She complained of hemoarthrosis and recurrent patellar dislocation in the early knee flexion phase. Plain radiography and computed tomography (CT) showed patellar malalignment (quadriceps angle 20°) and severe dysplasia of the trochlea of the femur (sulcus angle 170°). Surgery was performed, consisting of trochleoplasty in addition to proximal and distal realignment. Trochleoplasty was undertaken using a modified Dejour technique. After surgery, the patient complained of joint contracture. Arthroscopic release of fibrous tissue relieved symptoms and obtained normal range of motion without patellar dislocation. Postoperative radiography and CT demonstrated improvement of the quadriceps angle (10°) and sulcus angle (140°).
authors.affiliation: South Akita Orthopedic Clinic, Seiwakai, 96-2 Kaidousita, Syowa-Ookubo, Katagami 018-1401, Japan. horikawa@virgo.interq.or.jp
authors.forename: Akira
authors.initials: A
authors.lastname: Horikawa
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kodama
authors.forename: Naohisa
authors.initials: N
authors.lastname: Miyakoshi
authors.forename: Shin
authors.initials: S
authors.lastname: Yamada
authors.forename: Seiya
authors.initials: S
authors.lastname: Miyamoto
mesh_terms: D000293:Adolescent; D017760:Bone Malalignment / Q000601:surgery*; D005260:Female; D005269:Femur / Q000473:pathology* / Q000601:surgery; D006801:Humans; D010329:Patella / Q000601:surgery*; D031222:Patellar Dislocation / Q000000981:diagnostic imaging / Q000601:surgery*; D012008:Recurrence; D014057:Tomography, X-Ray Computed