title: Impaired joint motion and contractures in callus distraction and segment transport: a retrospective data analysis.
abstract: OBJECTIVE
  The temporary loss of motion of adjacent joints is a common complication after distraction osteogenesis of the lower limb. The aim of this study was to investigate the incidence of tendon contracture and impaired joint motion of the knee and/or ankle joint during and after callus distraction with a ring fixator.
  
  
  METHODS
  Twenty patients (2 female, 18 male, average age: 36 years) were surgically treated for callus distraction and segment transport with an external ring fixator after traumatic bone loss in 21 lower limbs. The impaired joint motion of the adjacent joints during and after treatment was evaluated.
  
  
  RESULTS
  During treatment, we observed the free range of motion (ROM) of the ankle joint in 4 cases (19 %), restricted motion in 11 cases (52 %), and complete loss of motion in 6 cases (33 %). After treatment,free ROM was observed in 12 cases (57 %), impaired motion in 3 cases (14 %), and fixed joint position in 6 cases (29 %, 2 arthrodesis). This represents an improvement of motion in eight cases (38 %) and an impairment in two cases (10 %). In 11 cases, the ROM remained unchanged. During treatment, six restrictions in extension (24 %) and five (33 %) restrictions in flexion occurred in the knee joint, ultimately resulting in one loss of extension and three losses of flexion after frame removal.
  
  
  CONCLUSIONS
  The impairment of joint motion during bone lengthening with an external ring fixator in the lower extremity occurs in most cases at the ankle joint. Various treatment options are available to address tendon shortening, but accompanying physiotherapy may prevent or moderate its onset.
authors.affiliation: Department of Traumatology, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: Lukas
authors.initials: L
authors.lastname: Zak
authors.forename: Gerald E
authors.initials: GE
authors.lastname: Wozasek
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000843:Ankle Joint / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000503:physiopathology*; D003286:Contracture / Q000175:diagnosis* / Q000209:etiology* / Q000503:physiopathology / Q000517:prevention & control; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000175:diagnosis* / Q000209:etiology* / Q000503:physiopathology / Q000517:prevention & control; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D019857:Osteogenesis, Distraction / Q000009:adverse effects* / Q000295:instrumentation; D011859:Radiography; D016059:Range of Motion, Articular; D012189:Retrospective Studies; D016896:Treatment Outcome