[Revision surgery in acute periprosthetic knee joint infections]

Reduction of pathogens in the knee joint by removal of infected periprosthetic soft tissue, irrigation and modular implant exchange of the total knee arthroplasty (TKA) to eliminate the infection and long-term preservation of the TKA.

Early infection of TKA (<4 weeks postoperatively); acute hematogenous TKA infection (symptom duration <3 weeks).

Delayed (>4 weeks postoperatively) or chronic TKA infection; TKA loosening; difficult-to-treat pathogens; critical soft tissue with draining sinus tract.

Excision of the wound or old surgical scar (= primary approach to the knee joint). Preparation of subcutaneous tissue. Opening the joint capsule. Removal of the old suture in tissue layers. Five tissue samples taken for microbiological and 1 tissue sample for histopathological examination using an unused instrument from the knee joint. Debridement of the upper recesses with complete synovectomy. Partial resection of Hoffa's fat body. Eversion of the patella. Resection of peripatellar soft tissue and infection membranes from the medial and lateral part of the capsule. Removal of the polyethylene inlay. Débridement of the posterior joint capsule with protection of vessels and nerve. Systematic removal of avital and infected periprosthetic tissue. Checking for correct fit of the femoral and tibial part of TKA. Antiseptic rinsing of the joint cavity with mechanical cleaning of the TKA. Extensive irrigation of the joint cavity by jet lavage (3-5 l saline solution). Glove change of the surgical team and new operation coverage. Inserting new polyethylene. Layerwise wound closure.

Removal of redon drain on postoperative day 2. Physiotherapy and CPM. Removal of cutaneous suture about 2 weeks postoperatively. Antibiotic treatment for 12 weeks postoperatively (2 weeks intravenous, 10 weeks per oral). Checking of inflammatory markers.

Using correct indications and therapy, up to 90% of patients with acute periprosthetic TKA infection can be successfully treated with infection elimination and TKA preservation.