Volkan Öztuna, Mehmet Çolak, Aziz Vurucu, Cengiz Yılmaz

Mersin University School of Medicine, Department of Orthopaedics, Mersin, Turkey

Keywords: Hip arthroplasty, prothesis, femoral head, diameter, vacuum test

Abstract

Objective: Size of prosthetic head for hip hemiarthroplasty operations has been estimated by measuring the femoral head by a caliper intraoperatively. In addition, surgeons test the trial heads in the acetabulum by a maneuver of reduction and dislocation. Than, they take a decision on the head size according to the sense of vacuum between the socket and the trial head (the so called “vacuum test”). In this study, we examined the reliability of this subjective test.
Patients and methods: In a series of fifteen hemiarthroplasty operations of the hip for femoral neck fractures, two orthopaedic surgeons conducted the vacuum test independently to estimate the correct size of the femoral head diameter.
Results: Interclass correlation was significant between the measurements made by two surgeons (95% CI: 0.83-0.98; p=0,015).
Discussion: The vacuum test can be used safely to take the final decision on the size of the prosthetic femoral head in hemiarthroplasty operations.