Importance of Hollow or Solid Centralizer for Polished, Collarless and Tapered Stems in Total Hip Arthroplasty

Comparing Hollow and Solid Centralizer Designs When Using a Polished, Collarless, Tapered Hip Prosthesis Stem (MS30). A Prospective, Randomized, Multicenter Study Evaluated by RadioStereometric Analysis (RSA).

The study aims at comparing the effect of hollow or solid centralizer designs on the long time fixation behaviour of hip prosthesis stems that are polished, tapered and collarless. In a prospective, controlled and randomized study comprising two groups of 30 patients/hips each, the patients will be followed up by RadioStereometric Analysis (RSA) for ten years. In completion general health questionnaires as well as hip specific scoring instruments will be used to evaluate patient satisfaction and outcome.The hypothesis of the study is that the different centralizers will result in different migration patterns of the stems, which might affect the risk for late aseptic loosening.

Study Overview

• Status: Completed
• Conditions: Total Hip Arthroplasty
• Intervention / Treatment: Procedure: Hollow Centralizer; Device: MS-30 femoral stem; Procedure: Solid Centralizer

• Study Type: Interventional
• Enrollment (Actual): 60
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Sweden
  • Skåne
    • Lund, Skåne, Sweden, 221 85
      • Department of Orthopedics, Skåne University Hospital, Lund University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 60 years to 85 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Primary osteoarthritis of the hip necessitating primary hip replacement
• Charnley classification group A and B
• Age 60 - 85 years old at the inclusion time of the study.

Exclusion Criteria:

• Secondary osteoarthritis
• Rheumatoid arthritis
• Malignant disease
• Severe osteoporosis
• Earlier fracture or operation in the hip to be operated on
• Peroperative fracture
• Ongoing corticosteroid (oral) or immunosuppressive medication
• Personal disorders (dementia, alcohol or drug abuse etc) suspected of making completion of the trial uncertain.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Hollow Centralizer; The stem used (MS30)was originally designed with a solid centralizer but has been redesigned to be used with a hollow centralizer.	Procedure: Hollow Centralizer; The stem used (MS30)was originally designed with a solid centralizer but has been redesigned to be used with a hollow centralizer. The patients are randomized to either solid or hollow centralizer; Device: MS-30 femoral stem; This is the stem used in the study.
Active Comparator: Solid Centralizer; The stem used (MS30)was originally designed with a solid centralizer but has been redesigned to be used with a hollow centralizer.	Device: MS-30 femoral stem; This is the stem used in the study.; Procedure: Solid Centralizer; The stem used (MS30)was originally designed with a solid centralizer but has been redesigned to be used with a hollow centralizer. The patients are randomized to either solid or hollow centralizer

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Radiostereometric Analysis (RSA)	This will measure the change in stem migration over time and be indicative of long term result.	The first postoperative day, 6 months, 1, 2, 5 and 10 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
x-ray	On standard x-rays the progress of radiolucent lines or other signs of loosening will be measured	The first postoperative day, 6 months, 1, 2, 5 and 10 years
Hip specific questionnaire	Hip disability and Osteoarthritis Score (HOOS) - this is a hip specific questionnaire that will measure how the operation has affected the patients hip function and pain situation	Preoperatively, 1, 2, 5 and 10 years
General health questionnaire	EuroQol (EQ-5D) - a standardized instrument for use as measure of general health outcome	Preoperatively, 1, 2, 5 and 10 years

Collaborators and Investigators

• Sponsor: Region Skane

Study record dates

Study Major Dates

• Study Start: February 1, 2003
• Primary Completion (Actual): February 1, 2004
• Study Completion (Actual): November 1, 2014

Study Registration Dates

• First Submitted: July 4, 2013
• First Submitted That Met QC Criteria: August 5, 2013
• First Posted (Estimate): August 7, 2013

Study Record Updates

• Last Update Posted (Estimate): November 26, 2014
• Last Update Submitted That Met QC Criteria: November 25, 2014
• Last Verified: November 1, 2014

More Information

Terms related to this study

• Keywords: Total Hip Arthroplasty; Radiostereometry; Stem design
• Other Study ID Numbers: Centralizer study