The investigators hypothesise that cementless one-stage exchange revision surgery can be performed in patients with chronically infected hip replacement with substantial benefits for the patients, in terms of fast rehabilitation, low re-revision rates and good long term results.

Inclusion Criteria:

• Patient with clinical signs of infection for more than 4 weeks, arising from total hip arthroplasty (primary and revision), resurfacing hip arthroplasty or hemi-hip arthroplasty
• Informed oral and written consent given

Exclusion Criteria:

• Life expectancy under 2 years
• Cognitive dysfunction
• Pre-operative unwillingness to receive blood
• Intravenous drug abuse
• Alcoholism
• Immunocompromised patients
• Patients receiving immunosuppressive medication
• Ongoing systemic inflammatory disease
• Poorly regulated diabetes mellitus
• Renal failure (requiring dialysis)
• Acute systemic inflammatory response syndrome with proven infection (sepsis)
• Signs of coexisting active long-term local infection (i.e. endocarditis)
• Previous two-stage revision of hip arthroplasty due to ipsilateral chronic infection (regardless of symptom free interval) or contralateral chronic infection (within the last 2 years).
• < 6 weeks since last surgery of the affected hip
• If definition of infection is not fulfilled: infection defined as Culture positive: ≥ 3 positive intraoperative cultures (tissue biopsies a.m. Kamme-Lindberg) Culture negative: < 3 positive intraoperative cultures (tissue biopsies a.m. Kamme-Lindberg) + Chronic fistula with history of previous or existing secretion or Positive cultures in pre-operatively joint fluid aspiration with other clinical signs of infection or Visual pus or purulent fluid during exchange procedure with clinical signs of infection