Bisphosphonates and Impaction Grafting in Hip Revision

Study Overview
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Brief Summary
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The primary focus of this study is to investigate whether increased bone density of the graft in revision arthroplasty of the hip can cause a decreased micromotion of the implant relative to the femur.

Detailed Description
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Morsellized compacted bone allograft can be used for revision arthroplasty of the hip. Treating the graft locally with an antiresorptive substance such as a bisphosphonate has decreased the graft resorption in animal studies and led to a remained bone density in a human series of 16 patients. In the present study we investigate if this increased bone density of the graft also causes a decreased micromotion of the implant relative the femur. 36 patients are planned to participate in a 1:1 randomized and prospective study comparing the bisphosphonate Clodronate to saline. Primary outcome will be micromotion over the first year but also secondary parameters such as late micromotion (between 12 and 24 months), re-loosening subjective outcome and safety. We hypothesize that rinsing the graft in a bisphosphonate solution prevents its resorption and therefore may reduce the risk of mechanical failure. Patients are followed with radiograms, RSA (radiostereography) preop, postop, at 6 weeks, at 12 and 24 months and subjective months and subjective parameters including Womac and SF 12. The treatment is simple, cheap and appears virtually risk-free.

Official Title
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Bisphosphonates and Impaction Grafting in Hip Revision Evaluated With Radiostereophotogrametri. A Randomized, Double-blind Study in Patients Operated for Aseptic Loosening and Osteolysis.

Conditions
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Aseptic Loosening of the Hip Prosthesis

Intervention / Treatment
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* Drug: Clodronate
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with aseptic loosening and osteolysis scheduled for hip revision using allograft and impaction technique Obtained informed consent Pregnancy excluded in women of childbearing age Exclusion Criteria: Patients with known renal disease or S-creatinine >175 mcmol/L Patients with S-calcium 2.75 mmol/L Patients with diagnosed Rheumatoid arthritis Patients with active primary hyperparathyroidism

Ages Eligible for Study
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Minimum Age: 45 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 1<br> | Drug: Clodronate<br>* 60 mg/ml, 10 ml, single dose mixed in bone graft at operation<br>|
| Placebo Comparator: 2<br> | Drug: Placebo<br>* 10 ml, single dose mixed in bone graft at operation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Decrease of prosthetic micromotion from 2.7 mm to 1.7 mm as measured by RSA (0-24 months) |  | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Decrease of prosthetic micromotion from 2.7 mm to 1.7 mm as measured by RSA (late micromotion) |  | 12-24 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Surgical procedures operative, Prosthesis implantation, Arthroplasty replacement