Evaluation of Stability of Two Uncemented Hip Implants Used for Total Hip Arthroplasty
|The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.|
|ClinicalTrials.gov Identifier: NCT02656771|
Recruitment Status : Active, not recruiting
First Posted : January 15, 2016
Last Update Posted : January 8, 2018
|First Submitted Date ICMJE||January 13, 2016|
|First Posted Date ICMJE||January 15, 2016|
|Last Update Posted Date||January 8, 2018|
|Study Start Date ICMJE||January 2016|
|Estimated Primary Completion Date||October 2019 (Final data collection date for primary outcome measure)|
|Current Primary Outcome Measures ICMJE
||Migration of the stem [ Time Frame: 2 years ]
The differences between the two stem designs are evaluated by measurements of migration of the stem assesed by Radiosteriometric analysis (RSA)
|Original Primary Outcome Measures ICMJE||Same as current|
|Change History||Complete list of historical versions of study NCT02656771 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures ICMJE
|Original Secondary Outcome Measures ICMJE||Same as current|
|Current Other Pre-specified Outcome Measures||Not Provided|
|Original Other Pre-specified Outcome Measures||Not Provided|
|Brief Title ICMJE||Evaluation of Stability of Two Uncemented Hip Implants Used for Total Hip Arthroplasty|
|Official Title ICMJE||Evaluation of Uncemented Echo Bi-Metric Full Proximal Profile THA Stem Versus Uncemented Bi-Metric Porous Primary THA Stem in a Randomized Controlled Trial Using RSA and DXA|
|Brief Summary||The purpose of this study is to measure quantitatively the implant stability and implant related remodeling of the periprosthetic femoral bone of the new uncemented Echo® Bi-Metric® Full proximal Profile total hip arthroplasty (THA) stem, and compare it to the classical uncemented Bi-Metric® Porous Primary THA stem by measuring migration of the stem assessed by model-based radiosteriometric analysis (MB-RSA) and measuring the periprosthetic adaptive bone remodeling assessed by dual-energy x-ray absorptiometry (DXA).|
Material and Methods Hypothesis The uncemented Echo® Bi-Metric® Full proximal Profile THA stem shows less migration and less bone loss of the periprosthetic bone compared to the uncemented Bi-Metric® Porous Primary THA stem.
Operation All operations will be performed by 4 experienced hip surgeons from the Hip unit at the Department of Orthopedic Surgery, Gentofte Hospital, Gentofte, Denmark. Each of the surgeons performs approximately 120 THA-operations a year.
Surgery is performed according to a standard procedure with a postero-lateral approach and following the manufacturers` recommendations. During surgery a minimum of 4 Tantalum markers (0.8mm) are inserted in the bone of the proximal femur for defining the bone segment in the RSA analysis. All patients receive the same uncemented hemispheric acetabular cup (Exceed) with a highly cross-linked polyethylene liner. No local analgesic is injected. Physiotherapy begins on the day of surgery and the patients will be mobilized with full weight-bearing using crutches. All patients will get oral anticoagulants according to praxis of the department (Xarelto until discharge), and prophylactic antibiotics (Dicloxacillin, 2 g preoperatively and 1g x 2 postoperatively) during the first 24 hours.
Calculations of sample size Migration (RSA). Several published RSA studies are available but none evaluating an uncemented Bi-Metric stem including data for the most clinically relevant migration between 1 and 2 years. Quite a lot of RSA studies evaluating migration of both cemented and uncemented femoral stems have been published, but most investigators give the variability of their RSA results as total range or standard error of mean. We have decided for our sample size calculation to use the average standard deviation (SD) -for the migration after 2 years of follow-up from two previously published studies (including data from one uncemented (n=22) and two cemented stems (n=82), where clear information regarding SD was available in the publication.
Investigators performed the calculation using the parameter MTPM two years postoperatively using:
Type I error = 5% Type II error = 15 % MIREDIF = 0.6 mm SD = 0.69 mm Calculation resulted in a sample size of n = 23 in each group.
Bone remodeling (DXA). The expected prospective decrease in BMD of the proximal femur after insertion of an uncemented THA is most pronounced in Gruen zones 1 and 7 with decreases of respectively 13-21% and 10-31%. In this study investigator intend to measure a significant difference (MIREDIF) in percentage changes in BMD between the two groups of 7.5%. Even though several studies evaluating prospective changes in BMD around a femoral stem have been published, investigator did not find a study with precise information of the SD of the percentages in BMD. Thus, investigator estimated a SD of the changes in BMD of 8% that could be used for calculating sample size in our study.
Type I error = 5% Type II error = 15% and MIREDIF = 7.5% SD = 8% Calculation resulted in a sample size of n = 20 in each group. Based upon the above sample size calculations for both RSA and DXA investigator have planned to include and randomize a total of: 60 patients.
This will secure a high statistical power of the study (even if some of the participants should drop out during the study) that can be kept even if the study is continued beyond 2 years of follow-up.
Randomization Allocation to the Echo® Bi-Metric® group or control group (Bi-Metric® group) is performed on a random basis (block randomization with 10 in each block). Randomization is done on the day of surgery with a closed non-transparent envelope opened in the operation theatre when the patient is ready for surgery.
Due to visual difference of the two prostheses, the surgeon and personnel present will know which of the prostheses the patient shall receive.
Ethical considerations This investigation will be performed in accordance with the principles of the Helsinki Declaration, and all patients will receive both oral and written information before informed consent to participate is obtained. It will be the investigators job to inform all patients until they completely understand all aspects of participation. At any time being the patient will be able to cancel participation (also without any explanation) in this investigation. The patient will receive the best possible treatment in any circumstance.
The study will not be started until approval from the Scientific Ethical Committee of the Capital Region of Denmark and the Danish Data Protection Agency has been obtained, and it will be registered at clinicaltrials.gov.
We do not expect the patients participating in the study to experience any specific side effects or complications related directly to the use of the two orthopedic implants. A potential difference between the two prostheses is expected only to be measurable using very precise techniques such as DXA and RSA.
Radiation dose to the patients from both RSA and DXA is low compared with conventional x-ray examinations. The total accumulated radiation dose to a patient participating in all examinations during the study is estimated to be approximately 0.1 mSv.
Tantalum has been used for more than 50 years and is a very biocompatible material. Tantalum beads for RSA have been used especially in Sweden in several clinical studies for more than 20 years. More than 20.000 beads have been implanted in more than 2.000 patients and no side effects from Tantalum beads have been observed.
Risks and inconveniences There will always be risks associated with operation. This investigation will not add to the general risks of getting THA. Patients participating must accept some inconvenience in terms of additional examinations and hence transportation to and from the hospitals.
Adverse events Adverse events are defined as any harmful and unwanted event, sign or symptom to occur in relation to this trial. All adverse events will be recorded in the CRF and will include details concerning the nature, onset, duration, severity, relationship to the device and relationship to the operative procedure and outcome. The affected patient(s) will be questioned about any adverse event(s) at each subsequent follow-up visit.
Patients experiencing adverse events will be relevantly monitored by clinical assessment and lab examinations decided by the treating physician. All adverse events will be monitored until recovery or stabilization.
Information and consent Patients who are planned to receive a THA (and fits within the inclusion and exclusion criteria of the study) at Gentofte Hospital will be informed about the trial in the preoperative interview. In addition to the oral information provided, the patients will be given written information. This conversation will take place in an enclosed space without distractions or interruptions. The patient will receive adequate verbal and written information about the purposes, processes, potential benefits and risks including possible side effects. Investigator will ensure all patients have read and understood the information and consent form. Patients will be informed that they are entitled to consideration before consent is given. The subjects will also be informed that it is voluntary and that they at any time may withdraw from the trial. It is the investigator's responsibility to ensure the above.
There will be obtained written informed consent from all subjects before enrollment, and a copy of the information and consent form will be given to the subjects.
Existing legislations made by the Scientific Ethical Committee regarding informed consent will be followed.
Data protection All information will be kept confidential, and all data handled according the guidelines of the Danish Data Protection agency. The persons involved in this trial are obliged to professional secrecy. The investigator will maintain a list of identification of all enrolled patients. This list will contain the patients' full names and dates of birth (including social security numbers (CPR-numbers)).
Collected data will be recorded in a case report form (CRF). CRFs and the medical records will be made available to third parties according to Danish law. Patients will be informed in writing that the results will be stored and analyzed in a computer which preserve patients' anonymity and that the local laws regarding personal data will be complied.
Patients will also receive written information concerning the possibility of audit from the public authorities, and patients will be informed that the GCP unit of Copenhagen University Hospital likewise is granted access.
Investigator ensures that the project will follow the rules of Good Clinical Practice.
|Study Type ICMJE||Interventional|
|Study Phase ICMJE||Not Applicable|
|Study Design ICMJE||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Participant)
Primary Purpose: Treatment
|Condition ICMJE||Osteoarthritis, Hip|
|Intervention ICMJE||Device: Echo Bi-Metric
The insertion of the Echo® Bi-Metric® THA stem
|Study Arms ICMJE||
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Recruitment Status ICMJE||Active, not recruiting|
|Actual Enrollment ICMJE
|Original Estimated Enrollment ICMJE
|Estimated Study Completion Date ICMJE||December 2022|
|Estimated Primary Completion Date||October 2019 (Final data collection date for primary outcome measure)|
|Eligibility Criteria ICMJE||
|Ages ICMJE||30 Years to 75 Years (Adult, Older Adult)|
|Accepts Healthy Volunteers ICMJE||No|
|Contacts ICMJE||Contact information is only displayed when the study is recruiting subjects|
|Listed Location Countries ICMJE||Denmark|
|Removed Location Countries|
|NCT Number ICMJE||NCT02656771|
|Other Study ID Numbers ICMJE||THA1-KD-14|
|Has Data Monitoring Committee||Not Provided|
|U.S. FDA-regulated Product||Not Provided|
|IPD Sharing Statement ICMJE||Not Provided|
|Responsible Party||Karen Dyreborg, Rigshospitalet, Denmark|
|Study Sponsor ICMJE||Rigshospitalet, Denmark|
|PRS Account||Rigshospitalet, Denmark|
|Verification Date||January 2018|
ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP