title: Painful prosthesis: approaching the patient with persistent pain following total hip and knee arthroplasty.
abstract: BACKGROUND
  Symptomatic severe osteoarthritis and hip osteoporotic fractures are the main conditions requiring total hip arthroplasty (THA), whereas total knee arthroplasty (TKA) is mainly performed for pain, disability or deformity due to osteoarthritis. After surgery, some patients suffer from "painful prosthesis", which currently represents a clinical problem.
  
  
  METHODS
  A systematic review of scientific literature has been performed. A panel of experts has examined the issue of persistent pain following total hip or knee arthroplasty, in order to characterize etiopathological mechanisms and define how to cope with this condition.
  
  
  RESULTS
  Four major categories (non infective, septic, other and idiopathic causes) have been identified as possible origin of persistent pain after total joint arthroplasty (TJA). Time to surgery, pain level and function impairment before surgical intervention, mechanical stress following prosthesis implant, osseointegration deficiency, and post-traumatic or allergic inflammatory response are all factors playing an important role in causing persistent pain after joint arthroplasty. Diagnosis of persistent pain should be made in case of post-operative pain (self-reported as VAS ≥3) persisting for at least 4 months after surgery, or new onset of pain (VAS ≥3) after the first 4 months, lasting ≥2 months. Acute pain reported as VAS score ≥7 in patients who underwent TJA should be always immediately investigated.
  
  
  CONCLUSIONS
  The cause of pain needs always to be indentified and removed whenever possible. Implant revision is indicated only when septic or aseptic loosening is diagnosed. Current evidence has shown that peri-and/or post-operative administration of bisphosphonates may have a role in pain management and periprosthetic bone loss prevention.
authors.affiliation: University of Florence, Florence, Italy ; Euro Mediterranean Biomedical Scientific Institute, ISBEM, Brindisi, Italy.
authors.forename: Prisco
authors.initials: P
authors.lastname: Piscitelli
authors.forename: Giovanni
authors.initials: G
authors.lastname: Iolascon
authors.forename: Massimo
authors.initials: M
authors.lastname: Innocenti
authors.forename: Roberto
authors.initials: R
authors.lastname: Civinini
authors.forename: Alessandro
authors.initials: A
authors.lastname: Rubinacci
authors.forename: Maurizio
authors.initials: M
authors.lastname: Muratore
authors.forename: Michele
authors.initials: M
authors.lastname: D'Arienzo
authors.forename: Paolo Tranquilli
authors.initials: PT
authors.lastname: Leali
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Carossino
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: Brandi
keywords: hip arthroplasty; knee arthroplasty; painful prosthesis; persistent pain