The Hip: Preservation, Replacement and Revision

Infected / Septic THR

 - See: Total Hip Replacement Menu:  and see total knee replacement infections

- Diagnosis:
    - diagnosis of septic loosening is initially based on history, x-ray findings, and elevated sed rate;
    - clincially patients may note increasing pain at both rest and with activity;
    - despite the variety of tests available, it may be difficult to distinguish aseptic loosening (acetabular and femoral) from
         an infected THR; 
    - risk factors:
         - Methods to Prevent Infection
                - references: Perioperative factors associated with septic arthritis after arthroplasty. Prospective multicenter study of 362 knee
                          and 2,651 hip operations. 
    - classification:
         - type I: early postoperative
         - type II: late chronic (two-stage revision arthroplasty)
         - type III: acute hematogenous (such as from dental procedures)
         - type IV: positive intraoperative cultures with clinically unapparent infection
                 - Prosthetic joint infection diagnosed postoperatively by intraoperative culture. 

  - Radiographs:
         - classic findings include, irregular or scalloped border on the endosteal surface of the cortex, marked periosteal reaction,
                  or late dislocation
         - dx of THR infection that is difficult to appreciate grossly is often delayed, especially in a patient w/o fever or severe pain;
                  - x-ray signs of loosening of prosthesis are seen in 2/3 of late infections, but in less than 50 % of early infections;
         - arthrography: (see: hip aspiration
                  - may be helpful for determining loosening of cemented acetabular components by showing penetration of dye between
                            cement and bone;
                  - note that a fibrous membrane between cement and bone will impede penetration of cement (false negative);
         - bone scans in THR:
                  - references:
                          - Evaluation of musculoskeletal sepsis with indium-111 white blood cell imaging.
                          - Asymptomatic total hip prosthesis:  Natural history determined using Tc-99MDP bone scans
- Laboratory Evaluation and Aspiration:
      - bacteriology:
              - currently staph epidermidis has emerged as the most common infectious organism followed closely by staph aureus;
              - above two bacterial species along with pseudomonas are slime producers (glycocalyx) which makes them particularly
                        resistant to treatment w/ antibiotics; 
              - gram negative organisms which do not produce a glycocalyx may not be as virulent as previously thought; 
              - consider need for Ziehl Nielsen stains, mycobacterial cultures, and fungal cultures; 
              - references:
                      - Methicillin-resistant Staphylococcus epidermidis in infection of hip arthroplasties.
                      - Deep infection of cemented total hip arthroplasties caused by coagulase negative staphylococci
                      - Total Hip Arthroplasty Infection With Chlamydia Pneumoniae and Mycobacterium Chelonae

  - Management: (see revision THR);
     - debridement and retension of components: (Tsukayama (1996)) 
          - Infection after total hip arthroplasty. A study of the treatment of one hundred and six infections.
     - one stage replantation:  
     - two stage replantation: 
     - antibiotic suppression:
           - success rate of 20-30%;
           - antibiotic treatment will not eliminate chronic deep infection about prosthesis;
           - antibiotic management can be used as suppressive treatment for established infection.
           - antibiotic suppression can be used if the following are met:
                    - prosthesis removal is not feasible (pt not candidate for anesthesia) 
                    - microorganism is of low virulence & susceptible to antibiotics;
                    - patient can tolerate antibiotic w/o serious toxicity;
                    - prosthesis is not loose; 
                    - ref: Conservative treatment of staphylococcal prosthetic joint infections in elderly patients
     - girdlestone arthroplasty

____________________________________________________  
- References: 

Treatment of Infection at the Site of Total Hip Replacement.   

Treatment of the septic hip with total hip arthroplasty.

Total Arthroplasty and the Veterans Administration--Symposium: Total Hip Arthroplasty: Infections at the Site of a Hip Implant Successful and Unsuccessful Management.

Pathobiology of infection in prosthetic devices.

The Use of Porous Prostheses in Delayed Reconstruction of Total Hip Replacements That Have Failed Because of Infection

Infection after total hip arthroplasty. A study of the treatment of one hundred and six infections

Acute and subacute deep infection after uncemented total hip replacement using antibacterial prophylaxis.

Antibiotic Susceptibility of Bacteria Infecting Total Joint Arthroplasty Sites.




Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Thursday, May 19, 2016 6:41 am