Same instrument setup safe to use for both sides in bilateral THA

No statistically significant differences in infections found between patients treated with different or the same instrument set.

Using the same instrument set for both sides during single-stage bilateral total hip arthroplasty appears as safe as surgery performed using two different instrument sets, according to a study by New York surgeons.

Alejandro González Della Valle, MD, and colleagues at the Hospital for Special Surgery conducted the study, which evaluated the bilateral total hip arthroplasty (THA) techniques performed by three surgeons between March 1986 and March 2003. They published their results in The Journal of Arthroplasty.

“Our findings fail to demonstrate a statistically significant difference in the rate of deep or superficial infections among patients operated on with different or the same set of sterile instruments,” the authors said in the study. “Thus, the use of the same set of instruments for the second side appears safe.”

However, the authors noted that their results should be interpreted cautiously. “With the prevalence of deep infection of the first and second side observed in this series, it would be necessary to analyze more than 2300 patients in each group to achieve statistical significance,” they said.

Surgical techniques

In the study, the researchers divided patients into two groups. One surgeon operated on the 279 Group I patients using a completely new sterile setup for each side, including new drapes, instrument tables and new sterile instruments. Eight patients were lost to follow-up, leaving 271 patients at an average six-year postop — 142 men and 129 women with an average age of 60 years at the time of surgery.

Group II included 229 patients treated by the remaining two surgeons, who began using the same sterile setup and instrument sets in January 1994, according to the study.

Researchers excluded five Group II patients who had less than one year of follow-up. The remaining 289 patients had an average follow-up of 42 months and included 175 men and 114 women with an average age of 56 years at surgery.

All surgeons used the posterolateral approach in the lateral decubitus and epidural anesthesia, according to the study.

One infection found in Group I

Researchers analyzed both groups’ infection rates over one year postop: the time during which patients are most likely to develop deep infections secondary to intraoperative contamination, they said.

In Group I, six months after surgery, the researchers found one deep infection (0.2%) on the first operated side of a 42-year-old man who was immunosuppressed for non-Hodgkin’s lymphoma treatment. Surgeons treated this patients with arthroscopic irrigation and debridement, and the infection remaind suppressed with antibiotics after eight years follow-up, according to the study.

The researchers also found a superficial wound infection on the first operated side of another patient, but this infection healed uneventfully with local care without readmission.

Patients in Group II did not show any signs of deep infection during the first year postop. However, one patient suffered a severe superficial infection on the first operated side, which required readmission and intravenous antibiotics, according to the study.

Another four patients developed mild superficial wound infections during the first six weeks after surgery — two on the first operated side and two on the second operated side. All resolved uneventfully with local care and oral antibiotics, the authors noted.

For more information:
González Della Valle A, Walter W, Peterson M, et al. Prevalence of infection in bilateral total hip arthroplasty. J Arthroplasty. 2006;21:157-160.