Preheating of Femur Component in Hybrid Total Hip Arthroplasty

Condition(s) targeted: Osteoarthritis, Hip

Intervention: Total hip replacement (Preheating of femur stem) (Procedure)

Phase: N/A

Status: Active, not recruiting

Sponsored by: Northern Orthopaedic Division, Denmark

Official(s) and/or principal investigator(s):
Mogens B Jørgensen, dr., Principal Investigator, Affiliation: Northern Orthopaedic Division
Mogens B Laursen, Ph.D, Principal Investigator, Affiliation: Northern Orthopaedic Division
Lotte Borgwardt, dr., Principal Investigator, Affiliation: Frederikberg Hospital, Copenhagen
Kjeld Søballe, Ph.D., MD., Study Chair, Affiliation: University Hospital of Aarhus
Poul T Nielsen, dr., Study Director, Affiliation: Northern Orthopaedic Division

Background

- Recently published studies confirm that preheating of femoral component enhances shear

strength of implant-cement interface. Both Iesaka et al 2003 and Jafri et al 2004 showed reduction in cement porosity on cement-implant interface with preheated femur components. We will use the radiostereometry analysis (RSA) to investigate how the preheating of femur component influence on prosthesis survivorship. There are no clinical controlled studies performed to the date.

The aim of the study

- Comparison of the migration rates between preheated and non-preheated femur components,

analyzed with RSA.

Methods

- We will randomize 80 patients into 2 groups with 40 in each. All the patients will

undergo standard hybrid total hip replacement. In group one the femur component (Bi-Metric, Interlock Biomet) will be preheated to 40 degrees of Celsius before cementation. In group two- also control group- the femur component will be of room temperature. We will measure the temperature at cement bone interface during the operation with use of thermocouple electrodes inserted through separate drill hole in the femur. The measurements will be recorded every 10 seconds. The patients will follow the standard postoperative rehabilitation program.

- The RSA analysis will be performed the first day after the operation and at 3, 12, 24

months postoperatively.

- The Dual-energy X-ray absorptiometry scanning (DEXA) of the femur will be performed at

the first week after the operation and at 12 and 24 months postoperatively.

- The patients will be followed both clinically and radiological at 1 and 2 years after

the operation (Harris Hip Score).

- The results will be expressed as mean + SD (in mm). ANOVA statistical analysis will be

used to confirm the differences between the groups.

Official title: Comparison Between Preheated and Non-Preheated Femur Component in Hybrid Total Hip Arthroplasty (THA) A Prospective Randomized Study of the 80 THA Using Radiostereometry.

Study design: Treatment, Randomized, Double-Blind, Active Control, Single Group Assignment, Efficacy Study

Primary outcome: Stem migration in mm

Secondary outcome:

Bone mineral density g/cm2

Temperature at bone-cement interface, degrees in Celsius

Serum- Titanium measurements in blood samples

Minimum age: 70 Years. Maximum age: 85 Years. Gender(s): Both.

Criteria:

Inclusion Criteria:

- The patients suffering of hip osteoarthritis

Exclusion Criteria:

- The patients with ASA score >II

- The patients with cancer

- The secondary coxarthrosis after the trauma

- Any vascular or neuromuscular diseases affecting the hip.

Farsoe Hospital, Northern Orthopaedic Division, Farsoe 9640, Denmark

Starting date: May 2006
Ending date: December 2010
Last updated: December 3, 2007