Aims

To analyse the effectiveness of debridement and implant retention (DAIR) in patients with hip periprosthetic joint infection (PJI) and the relationship to patient characteristics. The outcome was evaluated in hips with confirmed PJI and a follow-up of not less than two years.

Debridement, antibiotics and implant retention (DAIR) is an established treatment option for periprosthetic joint infection (PJI). Success rates of more than 90% cure have been reported with proper patient selection. While a meticulous debridement of the joint and an appropriate postoperative antibiotic therapy is important for treatment success, the relevance of changing mobile parts is still a matter of debate. The latter procedure is only possible with an extensive soft tissue release, potentially destabilizing the joint. Though, it is impossible with polyethylene-inlays being no longer available. The aim of this study was to evaluate whether cure of PJI with DAIR is influenced by retaining the mobile parts.

Between 01/2004 and 12/2012, 36 patients with 39 episodes of THA-associated infections were treated with DAIR according to our algorithm (NEJM 2004). All patients met the IDSA criteria for DAIR with a stable implant and either a PJI diagnosed during the first postoperative month or a haematogenous PJI with infectious symptoms of less than three weeks. Patients were treated either with a complete debridement, including an exchange of all mobile parts (n=24), or with a complete debridement and retaining mobile parts (n=15). Postoperatively all patients received standardized antibiotic treatment (NEJM 2004).

The patients’ mean age at the time of infection was 74 (SD 9) years. Average time between onset of symptoms and DAIR were 3.6 (0–28) days; Five patients died before the 2-year-follow-up unrelated to PJI. Mean follow-up of the remaining patients was 45.6 (24–119) months. 20 PJI were early postoperative, 15 haematogenously acquired, and four unclear. The most frequent causative microorganisms were coagulase-negative staphylococci (n=16), S. aureus (n=8), streptococci (n=5) and E. coli (n=2). Ten episodes were polymicrobial, and nine cases culture-negative. The overall success rate of all 39 episodes treated with DAIR was 95% (37/39). Two treatment failures were observed, both after haematogenous S. aureus infection and exchange of mobile parts. One of them refused further surgery and was treated with a suppressive antibiotic therapy. The other one had a one-stage exchange four months after DAIR showing a loose cup intraoperatively.

Patients treated with DAIR strictly according to our treatment algorithm show a favourable result regarding overall success rate. From our data it seems debatable, whether the exchange of all mobile parts is mandatory, or should be individually evaluated in each case.

The treatment of peri-prosthetic joint infection (PJI) of the ankle is not standardised. It is not clear whether an algorithm developed for hip and knee PJI can be used in the management of PJI of the ankle. We evaluated the outcome, at two or more years post-operatively, in 34 patients with PJI of the ankle, identified from a cohort of 511 patients who had undergone total ankle replacement. Their median age was 62.1 years (53.3 to 68.2), and 20 patients were women. Infection was exogenous in 28 (82.4%) and haematogenous in six (17.6%); 19 (55.9%) were acute infections and 15 (44.1%) chronic. Staphylococci were the cause of 24 infections (70.6%). Surgery with retention of one or both components was undertaken in 21 patients (61.8%), both components were replaced in ten (29.4%), and arthrodesis was undertaken in three (8.8%). An infection-free outcome with satisfactory function of the ankle was obtained in 23 patients (67.6%). The best rate of cure followed the exchange of both components (9/10, 90%). In the 21 patients in whom one or both components were retained, four had a relapse of the same infecting organism and three had an infection with another organism. Hence the rate of cure was 66.7% (14 of 21). In these 21 patients, we compared the treatment given to an algorithm developed for the treatment of PJI of the knee and hip. In 17 (80.9%) patients, treatment was not according to the algorithm. Most (11 of 17) had only one criterion against retention of one or both components. In all, ten of 11 patients with severe soft-tissue compromise as a single criterion had a relapse-free survival. We propose that the treatment concept for PJI of the ankle requires adaptation of the grading of quality of the soft tissues.

Cite this article: Bone Joint J 2014;96-B:772–7.