Evaluation of the Trabecular Metal™ Revision Hip Cup Using Bone Mineral Density (DEXA)

Evaluation of the Trabecular Metal™ Acetabular Revision Cup Using Dual-Energy X-ray Absorptiometry (DEXA)

In 1997, the FDA approved the use of Trabecular Metal™ (Zimmer, Trabecular Metal Technology, Inc., Parsippany, NJ) for acetabular cups, a porous tantalum structural biomaterial that was developed to address the limitations of other implant materials, with the potential to improve implant fixation.

Porous tantalum (80% porosity) offers potentially greater ingrowth and bone graft incorporation, believed to be restricted by the low porosity of other commonly used implants (30%). Additionally, the low modulus of elasticity property (3 MPa) of porous tantalum provides more normal physiological loading conditions which theoretically reduce stress shielding and resultant bone loss surrounding the implant. These properties are much desired advantages for implants used in cementless THA.

Various porous tantalum implants have shown favorable clinical results. Unger et al. reported excellent bone graft incorporation of the acetabular component based on serial radiograph data at a minimum 1-year follow-up.

Dual-energy X-ray absorptiometry (DEXA) is a well-established method for detecting periprosthetic bone mass changes around the femoral and acetabular THA components.

The primary objective of this study is to quantify and compare periprosthetic bone mineral density (BMD) changes in THA revision patients receiving Trabecular Metal™ and metal-backed acetabular components, measured using DEXA scanning techniques. Additionally, this study will analyze and compare clinical outcomes of these patients, based on SF-12v2 and HOOS.

Study Overview

• Status: Completed
• Conditions: Revision, Joint
• Intervention / Treatment: Device: Trabecular Metal Revision Cup; Device: Trabecular Metal Modular Cup

Detailed Description

none provided.

• Study Type: Interventional
• Enrollment (Actual): 25
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Ohio
    • Cleveland, Ohio, United States, 44195
      • The Cleveland Clinic

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 85 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age: 18 - 85 years
• Sex: Both male and female will be included. The male-to-female ratio will depend upon the patient population.
• Stable Health: At the time of surgery based on physical examination and medical history.
• Patient is a revision total hip recipient, which requires a metal-backed hemispherical cup.
• Patient or patient's legal representative has signed the Informed Consent form. The patient is capable of making informed decisions regarding his/her healthcare.

Exclusion Criteria:

• Patients undergoing bilateral surgery or had prior hip arthroplasty on contralateral side less than 6 months from date of surgery.
• Patients who do not plan to return to a Cleveland Clinic surgeon for follow-up visits (i.e. out of state/country patients who may choose to follow-up with a different surgeon).
• Patients with history of radiation therapy.
• Patients with known diagnosis of Brooker grade 3 or 4 HO (heterotopic ossification) in the hip joint region.
• Patients with known diagnosis of renal disease.
• Patients with known diagnosis of osteoporosis.
• Patients with history of steroid use in the hip joint region.
• Patients that have had a previous lumbar fusion.
• Patients whose surgical reconstruction required a pelvic cage or plate.
• Patient was a poor compliance risk - treated for ethanol or drug abuse, physical or mental handicap, etc.
• Any female of childbearing potential who is pregnant or is planning on becoming pregnant during the study period (~2 years postoperative).

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Trabecular Metal Revision Cup; Patients randomized to this arm will receive a trabecular metal revision component which does not have a titanium inner surface and requires a cemented highly crosslinked polyethylene liner.	Device: Trabecular Metal Revision Cup; Revision of the acetabular cup
Active Comparator: Trabecular Metal Modular Cup; Patients randomized to this arm will receive a trabecular metal modular component which has a titanium inner surface and requires a non-cemented highly crosslinked polyethylene liner.	Device: Trabecular Metal Modular Cup; Revision of the acetabular cup

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Periprosthetic Bone Mineral Density (BMD) of Hip	Quantify and compare periprosthetic bone mineral density (BMD) changes in THA revision patients receiving Trabecular Metal™ and metal-backed acetabular components, measured using DEXA scanning techniques. Region 1 forms the superior-lateral region, Region 2 forms the superior-medial region, and Region 3 forms the inferior-medial region around the acetabular component. For each region, the mean change in BMD was calculated using the following equation described by Wilkinson et al (J Bone Joint Surg Br., 2001): mean percent change in BMD = (BMD1-BMD2) x 2 x 100 / (BMD1 + BMD2). These regions were patient specific and remained the same each time the patient was scanned.	2 years postoperative; measured at 3 months (baseline), 6 months, 1 year, 2 year postoperative

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Functional and General Health Outcome Assessments	Analyze and compare functional and general health outcomes of these patients, based on Hip disability and Osteoarthritis Outcomes Score (HOOS) and 12-item Short Form Health Survey (SF-12v2). All subscale scores are calculated independently and range from 0 to 100, where 100 indicates no problems: SF-12 Physical Component Summary Subscale (SF12 PCS) assesses physical function, bodily pain, and general health.; SF-12 Mental Component Summary Subscale (SF12 MCS) assesses emotional and mental health.; HOOS Pain assesses pain in the hip; HOOS Symptoms assesses symptoms such as stiffness in the hip; HOOS activities of daily living (HOOS ADL) assesses physical function while performing common daily activities (walking, sitting, standing, etc.); HOOS sport and recreation (HOOS Sports/Rec) assesses physical function while performing higher-level activities (running, squatting, etc.); HOOS hip-related quality of life (HOOS QOL) assesses how much the hip impacts life	2 years postoperative; measured preoperatively and 3 months, 6 months, 1 year, 2 year postoperative

Collaborators and Investigators

• Sponsor: The Cleveland Clinic
• Collaborators: Zimmer Biomet

Study record dates

Study Major Dates

• Study Start: August 1, 2010
• Primary Completion (Actual): August 1, 2016
• Study Completion (Actual): January 1, 2017

Study Registration Dates

• First Submitted: August 13, 2010
• First Submitted That Met QC Criteria: August 13, 2010
• First Posted (Estimate): August 17, 2010

Study Record Updates

• Last Update Posted (Actual): November 7, 2017
• Last Update Submitted That Met QC Criteria: October 9, 2017
• Last Verified: October 1, 2017

More Information

Terms related to this study

• Keywords: bone mineral density; DEXA; trabecular metal; revision total hip arthroplasty
• Other Study ID Numbers: ZIMM1007WB; 09-859 (Other Identifier: CCF IRB)