The Metaphyseal Hip Prosthesis - Total Hip

Not Applicable

Completed

Conditions: Osteoarthritis of the Hip

Interventions: Device: Stanmore
Device: Metaphyseal Hip Prosthesis

Registration Number: NCT01501955

Lead Sponsor: Zimmer Biomet

Brief Summary: The purpose of this study is to analyze stability, safety and efficacy of the Metaphyseal Hip Prosthesis (MHP) compared to the Stanmore hip replacement.

Detailed Description: The purpose of this study is to analyze stability, safety and efficacy of the Metaphyseal Hip Prosthesis (MHP) compared to the Stanmore hip replacement at short term (1 year) and long term (10 years).

Bone remodeling will be analyzed at 10 years using DEXA (Dual Energy X-Ray Absorptiometry (bone scan test)) measurements.

This is a single-center prospective study with 25 patients in the study and 25 in the control group in open Randomized Clinical Trial.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 20

Inclusion Criteria

Candidates for a total hip replacement because of arthritis of the hip
Patients with a good general condition
Patients willing and able to participate in the clinical trial with a 10 years follow up and who have signed an inform consent
Males and females
Age between 55 and 75
Absence or little presence of osteoporotic bone (t>-2)
ASA score 1 and 2

Exclusion Criteria

Patient with co morbidities that limit the physical abilities which may negatively influence the scores. Such co morbidities can for example be cardiac insufficiency or chronic respiratory diseases.
Severe systematic diseases such as rheumatic arthritis and SLE.
General osteoporosis (t<-2).
Hormonal conditions such as Paget disease, which reduces the bone density.
Diseases that can negatively influence the 10 years life expectancy.
Chronic use of corticosteroids.
Extreme overweight defined as BMI above 35.
Active bacterial infection.
Mental weakness which could negatively influence the postoperative recovery and influence the ability to complete pain scores and other questionnaires.
ASA score >2.

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Stanmore	Stanmore	25 patients will have the Stanmore prosthesis
Metaphyseal Hip Prosthesis	Metaphyseal Hip Prosthesis	25 patients will have the Metaphyseal Hip Prosthesis (MHP) prosthesis

Primary Outcome Measures

Name	Time	Method
RSA Translation Z	3 months, 6 months, 1 year and 2 years postoperatively	Stem movement along z-axis in mm (measured with RSA)
RSA MTMP	3 months, 6 months, 1 year and 2 years postoperatively	Maximum Total Point Motion (MTPM) measured with RSA. This is a mean for the total migration of the stem.
RSA Translation X	3 months, 6 months, 1 year and 2 years postoperatively	Stem movement measured with RSA (radiostereometric analysis) along the x-axis in mm. RSA is a technique to accurately measure 3D movement of the prosthesis in the bone. The movement is measured with respect to the situation directly postoperative.
RSA Translation Y	3 months, 6 months, 1 year and 2 years postoperatively	Stem movement along the y-axis in mm. (measured with RSA)
RSA Rotation X	3 months, 6 months, 1 year and 2 years postoperatively	Stem Rotation around X-axis in degrees (measured with RSA)
RSA Rotation Y	3 months, 6 months, 1 year and 2 years postoperatively	Stem rotation around the y-axis in degrees ( measured with RSA)
RSA Rotation Z	3 months, 6 months, 1 year and 2 years postoperatively	Stem rotation around the z-axis in degrees (measured with RSA)

Secondary Outcome Measures

Name	Time	Method
Number of Reported Device Related Complications	6 weeks, 3 months, 6 months, 1, 2, 3, 4, 5, 6, 7, 10 years postoperatively	Safety: - Frequency of serious device related complications.
Harris Hip Score	pre-operatively, 6 weeks, 3 months, 6 months, 1, 2, 3, 4, 5, 6, 7, and 10 years postoperatively	Harris Hip Score (HHS), a score to measure health and satisfaction after a hip prosthesis. The score has a maximum of 100 points (best possible outcome) covering pain (1 item, 0-44 points), function (7 items, 0-47 points), absence of deformity (1 item, 4 points), and range of motion (2 items, 5 points)
DEXA	1 and 2 years postoperative	Efficacy: Bone density measured using the average DEXA score in each zone. For the long Stanmore the 7 Gruen zones were defined. For the short MHP stem an adjusted model with only 5 zones was used. The scan at 6 weeks is used as the baseline measurement to analyze if the bone density changes in the following years. At 1 year and 2 year follow up, percentual change is presented for both groups with respect to the 6 weeks DEXA score
HOOS-Pain Subscale	pre-operatively, 6 weeks, 3 months, 6 months, 1, 2, 3, 4, 5, 6, 7, and 10 years postoperatively	HOOS (Hip disability and Osteoarthritis Outcome Score) consists of 5 subscales; Pain, other Symptoms, Function in daily living (ADL), Function in sport and recreation (Sport/Rec) and hip related Quality of life (QOL). The last week is taken into consideration when answering the questions. Standardized answer options are given (5 Likert boxes) and each question gets a score from 0 to 4. A normalized score (100 indicating no symptoms and 0 indicating extreme symptoms) is calculated for each subscale.
HOOS-Symptom Subscale	pre-operatively, 6 weeks, 3 months, 6 months, 1, 2, 3, 4, 5, 6, 7, and 10 years postoperatively	HOOS consists of 5 subscales; Pain, other Symptoms, Function in daily living (ADL), Function in sport and recreation (Sport/Rec) and hip related Quality of life (QOL). The last week is taken into consideration when answering the questions. Standardized answer options are given (5 Likert boxes) and each question gets a score from 0 to 4. A normalized score (100 indicating no symptoms and 0 indicating extreme symptoms) is calculated for each subscale.
HOOS-ADL Subscale	pre-operatively, 6 weeks, 3 months, 6 months, 1, 2, 3, 4, 5, 6, 7, and 10 years postoperatively	HOOS consists of 5 subscales; Pain, other Symptoms, Function in daily living (ADL), Function in sport and recreation (Sport/Rec) and hip related Quality of life (QOL). The last week is taken into consideration when answering the questions. Standardized answer options are given (5 Likert boxes) and each question gets a score from 0 to 4. A normalized score (100 indicating no symptoms and 0 indicating extreme symptoms) is calculated for each subscale.
HOOS-Sport Subscale	pre-operatively, 6 weeks, 3 months, 6 months, 1, 2, 3, 4, 5, 6, 7, and 10 years postoperatively	HOOS consists of 5 subscales; Pain, other Symptoms, Function in daily living (ADL), Function in sport and recreation (Sport/Rec) and hip related Quality of life (QOL). The last week is taken into consideration when answering the questions. Standardized answer options are given (5 Likert boxes) and each question gets a score from 0 to 4. A normalized score (100 indicating no symptoms and 0 indicating extreme symptoms) is calculated for each subscale.
HOOS-QoL Subscale	pre-operatively, 6 weeks, 3 months, 6 months, 1,2, 3, 4, 5, 6, 7, and 10 years postoperatively	HOOS consists of 5 subscales; Pain, other Symptoms, Function in daily living (ADL), Function in sport and recreation (Sport/Rec) and hip related Quality of life (QOL). The last week is taken into consideration when answering the questions. Standardized answer options are given (5 Likert boxes) and each question gets a score from 0 to 4. A normalized score (100 indicating no symptoms and 0 indicating extreme symptoms) is calculated for each subscale.
SF-12 Physical Summary Score	pre-operatively, 6 weeks, 3 months, 6 months, 1, 2, 3, 4, 5, 6, 7, and 10 years postoperatively	12-Item Short-Form Health Survey (SF-12) presented in Physical (PS) and Mental summary (MS) scores (range 0-100). A zero score indicates the lowest level of health and 100 indicates the highest level of health.
SF-12 Mental Summary Score	pre-operatively, 6 weeks, 3 months, 6 months, 1, 2, 3, 4, 5, 6, 7, and 10 years postoperatively	SF-12 Score presented in Physical and Mental summary scores (range 0-100). A zero score indicates the lowest level of health and 100 indicates the highest level of health.