Early intra-articular complement activation in ankle fractures

Biomed Res Int. 2014;2014:426893. doi: 10.1155/2014/426893. Epub 2014 May 21.


Cytokine regulation possibly influences long term outcome following ankle fractures, but little is known about synovial fracture biochemistry. Eight patients with an ankle dislocation fracture were included in a prospective case series and matched with patients suffering from grade 2 osteochondritis dissecans (OCD) of the ankle. All fractures needed external fixation during which joint effusions were collected. Fluid analysis was done by ELISA measuring aggrecan, bFGF, IL-1 β, IGF-1, and the complement components C3a, C5a, and C5b-9. The time periods between occurrence of fracture and collection of effusion were only significantly associated with synovial aggrecan and C5b-9 levels (P < 0.001). Furthermore, synovial expressions of both proteins correlated with each other (P < 0.001). Although IL-1 β expression was relatively low, intra-articular levels correlated with C5a (P < 0.01) and serological C-reactive protein concentrations 2 days after surgery (P < 0.05). Joint effusions were initially dominated by neutrophils, but the portion of monocytes constantly increased reaching 50% at day 6 after fracture (P < 0.02). Whereas aggrecan and IL-1β concentrations were not different in fracture and OCD patients, bFGF, IGF-1, and all complement components were significantly higher concentrated in ankle joints with fractures (P < 0.01). Complement activation and inflammatory cell infiltration characterize the joint biology following acute ankle fractures.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Ankle Fractures / metabolism*
  • Ankle Fractures / pathology
  • Ankle Fractures / therapy
  • Ankle Joint / metabolism*
  • Ankle Joint / pathology
  • Complement Activation*
  • Complement System Proteins / metabolism
  • Fibroblast Growth Factor 2 / metabolism
  • Gene Expression Regulation
  • Humans
  • Insulin-Like Growth Factor I / metabolism
  • Interleukin-1beta / metabolism
  • Male
  • Middle Aged
  • Osteochondritis Dissecans / metabolism
  • Osteochondritis Dissecans / pathology
  • Osteochondritis Dissecans / therapy
  • Time Factors


  • IGF1 protein, human
  • IL1B protein, human
  • Interleukin-1beta
  • Fibroblast Growth Factor 2
  • Insulin-Like Growth Factor I
  • Complement System Proteins