Hip Arthrosis
Conditions
Keywords
RSA, DXA, Bisphosphonates, Migration of stem, Aseptic loosening of prosthesis
Brief summary
Periprosthetic bone-loss after total hip arthroplasty (THA), detected as an early migration of the prosthesis, may predict later loosening. The investigators hypothesized that by reducing bone resorption after THA with bisphosphonates, it might be possible to achieve better early fixation of the implant. Nineteen patients suffering arthrosis were recruited to a prospective, double-blinded, randomized, placebo-controlled clinical pilot trial. Patients were operated with an uncemented Bimetric stem with tantalum markers, the acetabular cup and liner were chosen by the surgeon. The femoral proximal intramedullary canal was rinsed with 1mM (millimole) clodronate, that was done by adding the clodronate to the 1000 ml 0.9% NaCl (sodium chloride) in nine patients and rinsing solution was the pure 0.9% NaCl for 10 patients. These rinsing packages were labeled only with the code from the pharmacy of the hospital. These patients were followed for two years using radiostereometric analysis (RSA), dual energy x-ray absorptiometry (DXA) and the Harris hip score (HHS). The purpose of the investigator's study was to examine whether the local intraoperative administration of clodronate could reduce periprosthetic bone loss and further stem migration after primary THA.
Interventions
DRUGClodronate
DRUGSaline
Sponsors
University of Oulu
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Investigator)
Masking description
Patients were randomized into two treatment groups; either the clodronate or a placebo group. All patients, surgeons and other personnel in the operating theatre were blinded as to the patients' study group.
Intervention model description
In this prospective, double-blinded, randomized, placebo-controlled clinical trial with two years follow-up period the investigators rinsed the proximal intramedullary cavity of the femur with either clodronate (60 mg clodronate in 1000 ml saline) or saline (1000 ml saline) prior to the application of the femoral stem.
Eligibility
Sex/Gender
ALL
Age
No minimum to 73 Years
Healthy volunteers
No
Inclusion criteria
* hip arthrosis and * a primary THA was planned
Exclusion criteria
* renal insufficiency * hypercalcemia * malignant tumors * contemporaneously treatment with another bisphosphonate or aminoglycoside
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Maximal total point motion (MTPM) - migration of the femoral stem | 0 to 24 months | It represents the length of the translation vector of the point in a rigid body that has the greatest motion. It can only have positive values, and is not normally distributed. The reason for using MTPM is that in many cases, motion implies a biological effect of some kind and this effect is liable to be greatest at the point of maximum motion. The parameter has been measured by RSA-methods, which is an accurate method of determining the migration and wear of orthopaedic implants: it determine the precise location of two distinct objects relative to each other in three dimension such as the relative position of the femoral component and the proximal femur. In radiostereometric analysis the position in space of the original object is reconstructed from a two dimensional x-ray film using tantalum beads. Movement between segments is then calculated by localizing each segment in a coordinate system. Lower values represent a better outcome. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Bone mineral density (BMD) in 7 Gruen zones | 0 to 24 months | BMD was measured by dual-energy X-ray absorptiometry, DXA. In clinical use, precision errors are \< 5 %. To evaluate the horizontal linear distribution of the BMD, seven Gruen zones, peri-prosthetic sub-regions of interest, ROI (region of interest) were calculated by the software on the anteroposterior view of the proximal femur. The value of BMD is g/cm2 and it estimates the strength of the bone. Higher values/lesser decrease in values represent a better outcome. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Migration of femoral stem | 0 to 24 months | Subsidence and vertical movement of the femoral stem (scale micrometers), x-, y- and z-translations. Parameters were measured using RSA-methods and the scaling is linear. Lower values represent a better outcome. |
| The maximal (MTPM) maximal total point motion | 3 to 24 months | The maximal MTPM value after 3 months when the expected integration of stem should have happened. Lower values represent a better outcome. |
| Correlation between baseline BMD and the maximal MTPM | BMD (0 month) - the maximal MTPM 3 to 24 months | This parameters summarize the BMD and RSA values together. The investigators have planned it to evaluate the correlation between the quality of periprosthetic bone in baseline and the migration of femoral stem during 2 years follow-up period between the study groups. |
| Harris Hip Score (HHS) | 0 to 24 months | Harris Hip Score (HHS) is a clinician-based outcome measure, health status scale, that is frequently used to measure the outcome of total hip arthroplasty. It is measured by questionnaire that give points from 0 to 100. Higher values represent a better outcome. |
Outcome results
None listed