title: Postoperative deep infection in tumor endoprosthesis reconstruction around the knee.
abstract: BACKGROUND
  Although deep infection remains one of the most difficult complications to manage in the treatment of musculoskeletal tumor reconstructed with an endoprosthesis, limited information with respect to its incidence and risk factors has been reported.
  
  
  METHODS
  This multicenter, retrospective, uncontrolled study reviewed the medical records of 82 patients who underwent reconstruction with an endoprosthesis or temporary spacer for bone-immature patients after resection of malignant bone tumor around the knee. Risk factors for deep infection and the impact of deep infection on prosthesis survival and oncological outcomes were analyzed. Deep infection was defined according to the Centers for Disease Control and Prevention (CDC) guidelines with minor modification.
  
  
  RESULTS
  Deep infection occurred in 14 cases (17%), identified at a mean of 10.9 months (range <1 to 48 months) after initial surgery. Univariate analysis identified surface infection (P < 0.001) and skin necrosis (P < 0.001) as risk factors associated with deep infection. Conversely, tumor origin, chemotherapy, number of postoperative antibiotics, and length of bone resection were not associated with infection. Subclass analysis in femur cases identified a correlation between infection and the extent of partial resection of the quadriceps muscle (P = 0.04). In the multivariate analysis, surface infection represented an independent risk factor for deep infection (P = 0.03). Deep infection was a risk for endoprosthesis survival (P = 0.003) but did not affect the oncological outcome.
  
  
  CONCLUSIONS
  A strong correlation between the condition of soft tissue and establishment of deep infection is suggested in this study. Although practical options for preventing deep infection seem limited, the present data allow a form of perioperative evaluation for patients with a higher risk of deep infection.
authors.affiliation: Department of Orthopaedic Surgery, Kyorin University, Tokyo, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Morii
authors.forename: Hiroo
authors.initials: H
authors.lastname: Yabe
authors.forename: Hideo
authors.initials: H
authors.lastname: Morioka
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Beppu
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Chuman
authors.forename: Akira
authors.initials: A
authors.lastname: Kawai
authors.forename: Ken
authors.initials: K
authors.lastname: Takeda
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Kikuta
authors.forename: Seiichi
authors.initials: S
authors.lastname: Hosaka
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Yazawa
authors.forename: Katsuhito
authors.initials: K
authors.lastname: Takeuchi
authors.forename: Ukei
authors.initials: U
authors.lastname: Anazawa
authors.forename: Kazuo
authors.initials: K
authors.lastname: Mochizuki
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Satomi
mesh_terms: D000369:Aged, 80 and over; D001859:Bone Neoplasms / Q000601:surgery*; D002675:Child, Preschool; D005260:Female; D005269:Femur / Q000601:surgery; D006801:Humans; D053208:Kaplan-Meier Estimate; D007717:Knee / Q000601:surgery*; D023821:Limb Salvage; D008297:Male; D019919:Prosthesis Implantation / Q000009:adverse effects*; D012189:Retrospective Studies; D013530:Surgical Wound Infection / Q000209:etiology*; D013977:Tibia / Q000601:surgery