title: Functional outcome after surgery in patients with bone sarcoma around the knee; results from a long-term prospective study.
abstract: OBJECTIVE
  In a previous conducted study functional outcome of young patients with bone sarcoma located around the knee was longitudinally evaluated during the first 2 years postoperatively. Functional outcome improved significantly over the first 2 years. The purpose of this descriptive study was to evaluate the functional outcome of these patients at long-term follow-up of 7 years.
  
  
  METHODS
  Functional outcome was assessed with the TESS, MSTS, Baecke questionnaire, and three functional performance tests: time up and down stairs (TUDS), various walking activities (VWA), and the 6-min walking test (6MWT). Linear Mixed Model has been employed for the repeated measurements.
  
  
  RESULTS
  Twenty patients of the original study (n = 44) participated in the current study. Fifteen limb-salvage and five ablative surgery patients, median follow-up 7.4 years (6.8-8.0) (CI 95%), mean age 22.3 years (18.2-31.6). Between 2 and 7 years after surgery, 8 limb-salvage patients (53%) encountered surgery related complications. Questionnaires and functional performance tests showed no significant difference in functional outcome between 2 years and 7 years after surgery (P < 0.05).
  
  
  CONCLUSIONS
  Between 2 years and follow-up at average 7 years after surgery no further improvements were noticed at young patients with a bone sarcoma located around the knee.
authors.affiliation: Department of Orthopedics, Rehabilitation & Physical Therapy, Leiden University Medical Centre, Leiden, Netherlands.
authors.forename: Janneke C
authors.identifier: http://orcid.org/0000-0001-7289-1226
authors.initials: JC
authors.lastname: van Egmond-van Dam
authors.affiliation: Department of Orthopedics, Rehabilitation & Physical Therapy, Leiden University Medical Centre, Leiden, Netherlands.|Department of Orthopedic Surgery, Academic Medical Center University of Amsterdam, Amsterdam, Netherlands.
authors.forename: W Peter
authors.initials: WP
authors.lastname: Bekkering
authors.affiliation: Department of Orthopedic Surgery, Academic Medical Center University of Amsterdam, Amsterdam, Netherlands.
authors.forename: Jos A M
authors.initials: JAM
authors.lastname: Bramer
authors.affiliation: Department of Pediatric Oncology/Hematology, Erasmus MC University Medical Center-Sophia Children's Hospital, Rotterdam, Netherlands.
authors.forename: Auke
authors.initials: A
authors.lastname: Beishuizen
authors.affiliation: Mathematical Institute Leiden University, Leiden, Netherlands.|Department of Medical Statistics and Bioinformatics, Leiden University Medical Centre, Leiden, Netherlands.
authors.forename: Marta
authors.initials: M
authors.lastname: Fiocco
authors.affiliation: Department of Orthopedics, Rehabilitation & Physical Therapy, Leiden University Medical Centre, Leiden, Netherlands.
authors.forename: P D Sander
authors.initials: PDS
authors.lastname: Dijkstra
mesh_terms: D000293:Adolescent; D000328:Adult; D001859:Bone Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007719:Knee Joint; D023821:Limb Salvage; D008297:Male; D012516:Osteosarcoma / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D011446:Prospective Studies; D020127:Recovery of Function; D013997:Time Factors; D016896:Treatment Outcome; D016138:Walking; D055815:Young Adult
keywords: follow-up; functional outcome; knee; malignant bone sarcoma; young patients