The Comparison of 32mm and 28mm Head Components in Alumina-alumina Total Hip Arthroplasty

Study Overview
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Brief Summary
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It has been postulated that use of a larger femoral head could reduce the risk of dislocation after total hip arthroplasty, but only limited clinical data have been presented in third generation alumina bearings. The purpose of this study is to evaluate the effect of femoral head size for total hip arthroplasty using third generation alumina bearings on the joint stability and clinical results. The investigators hypothesized that larger ceramic head group has a similar rate of dislocation and clinical results in smaller ceramic head group.

Official Title
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The Comparison of 32mm and 28mm Head Components in Alumina-alumina Total Hip Arthroplasty: A Randomized Clinical Trial

Conditions
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Arthroplasty, Replacement, Hip

Intervention / Treatment
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* Device: 32mm ceramic head group
* Device: 28mm ceramic head group


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: osteonecrosis of femoral head primary or secondary osteoarthritis of the hips femoral neck fracture Exclusion Criteria: previous hemi- or total hip arthroplasty highly dislocated or severe ankylosed hip patients who are considered potentially unreliable or who may not reliably attend study visits

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 85 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 |
| --- | --- |
| Active Comparator: 32mm ceramic head group<br>patients performed with THA using 32mm ceramic head | Device: 32mm ceramic head group<br>* we performed THA using 32mm ceramic head in this group.<br>|
| Active Comparator: 28mm ceramic head group<br>patients performed with THA using 28mm ceramic head | Device: 28mm ceramic head group<br>* we performed THA using 28mm ceramic head in this group.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| rate of dislocation in each head size | to evaluate the null hypothesis that the dislocation rate of larger ceramic head group is similar to smaller ceramic head group. | 6 weeks | 
| rate of dislocation in each head size | to evaluate the null hypothesis that the dislocation rate of larger ceramic head group is similar to smaller ceramic head group. | 3 months | 
| rate of dislocation in each head size | to evaluate the null hypothesis that the dislocation rate of larger ceramic head group is similar to smaller ceramic head group. | 6 months | 
| rate of dislocation in each head size | to evaluate the null hypothesis that the dislocation rate of larger ceramic head group is similar to smaller ceramic head group. | 9 months | 
| rate of dislocation in each head size | to evaluate the null hypothesis that the dislocation rate of larger ceramic head group is similar to smaller ceramic head group. | 12 months | 
| rate of dislocation in each head size | to evaluate the null hypothesis that the dislocation rate of larger ceramic head group is similar to smaller ceramic head group. | 24 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| clinical results using Harris Hip Score | to compare the clinical results such as pain, function, range of motion between both groups. | 6 weeks | 
| clinical results using Harris Hip Score | to compare the clinical results such as pain, function, range of motion between both groups. | 3 months | 
| clinical results using Harris Hip Score | to compare the clinical results such as pain, function, range of motion between both groups. | 6 months | 
| clinical results using Harris Hip Score | to compare the clinical results such as pain, function, range of motion between both groups. | 9 months | 
| clinical results using Harris Hip Score | to compare the clinical results such as pain, function, range of motion between both groups. | 12 months | 
| clinical results using Harris Hip Score | to compare the clinical results such as pain, function, range of motion between both groups. | 24 months |