Total Hip Arthroplasty in a hip with a previous history of infection.

Septic arthritis of the hip joint can result in infective chondrolysis with the development of secondary osteoarthritis, or may occur in a joint with existing osteoarthritis. Patients with an inflammatory arthropathy are also at an increased risk of the development of acute septic arthritis.

The initial management of septic arthritis of the hip includes urgent aspiration for confirmation of the diagnosis and isolation of the causative organism. This is followed by urgent joint washout. At present we recommend an open technique using several litres of saline, rather than arthroscopic washout. This is repeated as necessary if the clinical picture suggests persistence of infection..Intravenous high dose antibiotic therapy is initiated in close liaison with the Department of Microbiology, with continued shared care. Once the clinical picture suggests the infection is resolving, oral rather than intravenous antibiotics are continued, if appropriate. If prolonged intravenous therapy is deemed necessary, an intravenous long line or tunnelled line is inserted to facilitate administration of intravenous antibiotics, in the community if appropriate. The duration of antibiotic therapy depends on the clinical picture, but is usually for 6 weeks.

Patients with resolved septic arthritis or a past history of osteomyelitis adjacent to the joint may develop intrusive symptoms from joint degeneration raising the issue of the role of subsequent joint replacement.

Our current management of such cases involves:

1. Counselling of the patient and their family as to the risks and realistic benefits of THA following previous infection. This includes the increased risk of sepsis following the THA.
2. Confirmation of the causative organism as far as possible, including further joint aspiration or biopsy if any concern exists about persistence of infection.
3. Thorough debridement of the joint and insertion of an articulating antibiotic loaded cement spacer system is performed if there is any concern about the persistence of latent infection ( KIWI spacer – see section on 2 stage revision of an infected THA.).  Post operative antibiotics are stopped after 6 weeks. If the CRP remains within normal ranges after 2 further weeks without antibiotics, the definitive THA is inserted. If a 2 stage procedure is not deemed necessary, appropriately antibiotic loaded cement is employed, and post operative antibiotics are continued until the results of enrichment cultures are available. If these are negative, antibiotic therapy is ceased.