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

Not Applicable

Completed

Conditions: Revision, Joint

Interventions: Device: Trabecular Metal Revision Cup
Device: Trabecular Metal Modular Cup

Registration Number: NCT01183260

Lead Sponsor: The Cleveland Clinic

Brief Summary: 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.

Detailed Description: none provided.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 25

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 & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Trabecular Metal Revision Cup	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.
Trabecular Metal Modular Cup	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.

Primary Outcome Measures

Name	Time	Method
Periprosthetic Bone Mineral Density (BMD) of Hip	2 years postoperative; measured at 3 months (baseline), 6 months, 1 year, 2 year postoperative	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.

Secondary Outcome Measures

Name	Time	Method
Functional and General Health Outcome Assessments	2 years postoperative; measured preoperatively and 3 months, 6 months, 1 year, 2 year postoperative	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