title: Computer-assisted surgery in orthopedic oncology.
abstract: OBJECTIVE
  In orthopedic oncology, computer-assisted surgery (CAS) can be considered an alternative to fluoroscopy and direct measurement for orientation, planning, and margin control. However, only small case series reporting specific applications have been published. We therefore describe possible applications of CAS and report preliminary results in 130 procedures.
  
  
  METHODS
  We conducted a retrospective cohort study of all oncological CAS procedures in a single institution from November 2006 to March 2013. Mean follow-up time was 32 months. We categorized and analyzed 130 procedures for clinical parameters. The categories were image-based intralesional treatment, image-based resection, image-based resection and reconstruction, and imageless resection and reconstruction.
  
  
  RESULTS
  Application to intralesional treatment showed 1 inadequate curettage and 1 (other) recurrence in 63 cases. Image-based resections in 42 cases showed 40 R0 margins; 16 in 17 pelvic resections. Image-based reconstruction facilitated graft creation with a mean reconstruction accuracy of 0.9 mm in one case. Imageless CAS was helpful in resection planning and length- and joint line reconstruction for tumor prostheses.
  
  
  CONCLUSIONS
  CAS is a promising new development. Preliminary results show a high number of R0 resections and low short-term recurrence rates for curettage.
authors.affiliation: Department of Orthopedic Surgery , University of Groningen, University Medical Center Groningen, Groningen , the Netherlands.
authors.forename: Jasper G
authors.initials: JG
authors.lastname: Gerbers
authors.forename: Martin
authors.initials: M
authors.lastname: Stevens
authors.forename: Joris Jw
authors.initials: JJ
authors.lastname: Ploegmakers
authors.forename: Sjoerd K
authors.initials: SK
authors.lastname: Bulstra
authors.forename: Paul C
authors.initials: PC
authors.lastname: Jutte
mesh_terms: D050398:Adamantinoma / Q000000981:diagnostic imaging / Q000601:surgery; D000328:Adult; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery*; D005357:Fibrous Dysplasia of Bone / Q000000981:diagnostic imaging / Q000601:surgery; D005471:Fluoroscopy; D005500:Follow-Up Studies; D005870:Giant Cell Tumors / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D007432:Intraoperative Period; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging / Q000601:surgery; D019637:Orthopedic Procedures / Q000379:methods*; D015831:Osteochondroma / Q000000981:diagnostic imaging / Q000601:surgery*; D012516:Osteosarcoma / Q000000981:diagnostic imaging / Q000601:surgery*; D019651:Plastic Surgery Procedures / Q000379:methods*; D012189:Retrospective Studies; D012512:Sarcoma, Ewing / Q000000981:diagnostic imaging / Q000601:surgery; D025321:Surgery, Computer-Assisted / Q000379:methods*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome