Evaluation of Triathlon - A New Total Knee Prosthesis System - Roentgen Stereophotogrammetric Analysis (RSA) Triathlon CR vs. PS

Not Applicable

Completed

Conditions: Arthroplasty, Replacement, Knee

Interventions: Device: Triathlon PS
Device: Triathlon CR

Registration Number: NCT02522728

Lead Sponsor: Stryker Orthopaedics

Brief Summary: The objective is to investigate the Clinical, Radiographic, Roentgen Stereophotogrammetric behaviour and patient outcome when using the Triathlon total knee prosthesis in a prospective randomized clinical trial.

Detailed Description: The objective is to investigate the Clinical, Radiographic, Roentgen Stereophotogrammetric behaviour and patient outcome when using the Triathlon total knee prosthesis in a prospective randomized clinical trial.

The evaluation is carried out by a prospective randomised RSA-study with Triathlon CR vs. Triathlon PS.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 58

Inclusion Criteria

Patients suffering exclusively from osteo arthritis, Stage II-V [Ahlbäck, 1968 391] will be operated.
Patients requiring knee prosthesis, suitable for the use of Duracon and Triathlon knee system
Patients who understand the conditions of the study and are willing and able to comply with the post-operative scheduled clinical and radiographical evaluations and the prescribed rehabilitation.
Patients who signed the Ethics Committee approved Informed Consent Form prior to surgery.

Exclusion Criteria

Previous major knee surgery
Other significant disabling problems from the muscular-skeletal system than in the knees
Obese patients where obesity is severe enough to affect subject's ability to perform activities of daily living (body mass index, kg/m2: BMI above 35).
Patients with active or suspected infection.
Patients with malignancy - active malignancy.
Patients with severe osteoporosis, Paget's disease, renal osteodystrophy.
Patients immunologically suppressed, or receiving steroids in excess of physiologic dose requirements.
The patient has a neuromuscular or neurosensory deficit which would limit the ability to assess the performance of the device or the patient has a neurological deficit which interferes with the patient's ability to limit weight bearing or places an extreme load on the implant during the healing period.
Female patients planning a pregnancy during the course of the study.
Patients with systemic or metabolic disorders leading to progressive bone deterioration.
Patients, who as judged by the surgeon, are mentally incompetent or are unlikely to be compliant with the prescribed post-operative routine and follow-up evaluation schedule.
Patients with other severe concurrent joint involvements, which can affect their outcome.
Patients with other concurrent illnesses, which are likely to affect their outcome such as sickle cell anaemia, systemic lupus erythematosus or renal disease requiring dialysis.
Patients under the protection of law (e.g. guardianship).

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Triathlon PS	Triathlon PS	Triathlon Cruciate Retaining (CR) versus Triathlon Posterior Stabilized (PS): During knee prosthesis surgery the surgeon many times need to make a judgement on if to keep a defect anatomical structure or if to replace it with knee prosthesis with a design that allows for adjustment of this defect. This study is aimed to evaluate which prosthetic choice to be made in respect of stability, long-term results and patient outcome.
Triathlon CR	Triathlon CR	Triathlon Cruciate Retaining (CR) versus Triathlon Posterior Stabilized (PS): During knee prosthesis surgery the surgeon many times need to make a judgement on if to keep a defect anatomical structure or if to replace it with knee prosthesis with a design that allows for adjustment of this defect. This study is aimed to evaluate which prosthetic choice to be made in respect of stability, long-term results and patient outcome.

Primary Outcome Measures

Name	Time	Method
Assessment of Fixation and Stability of the Triathlon Total Knee Prosthesis by Roentgen Stereophotogrammetric Analysis (RSA)	2 years follow-up	Roentgen Stereophotogrammetric Analysis (RSA) is a technique to measure migration of prosthesis components relative to the bone which allows conclusions regarding the fixation of an implant. This study assesses the fixation and stability of the Triathlon total knee prosthesis at 2 years by RSA as a predictor of late mechanical loosening.

Secondary Outcome Measures

Name	Time	Method
Investigation of Clinical Performance and Patient Outcome With the Knee Society Score (KSS)	pre-operative, 3 months, 1, 2, 5, 7 and 10 years	The Knee Society Clinical Rating System is comprised of two distinct sub-scores: 1. assessment score for pain, range of motion (ROM) and joint stability, 2. score for functional parameters. Sub-scores range from a potential minimum score of 0 to a maximum score of 100 points. Although the specific scores are not distinguished as "excellent," "good," "fair," or "poor," a higher value represents a better outcome.
Investigation of Clinical Performance and Patient Outcome With EuroQuol-5 Dimension (EQ-5D) Patient Questionnaire	1, 2, 5, 7 and 10 years	The EQ-5D is a subject-completed questionnaire designed to assess subject health state values. The EQ-5D consists of 2 areas; EQ-5D descriptive system and the EQ visual analogue scale (EQ VAS). The EQ-5D descriptive system comprises the following five dimensions: mobility self care, usual activities, pain/comfort and anxiety/depression. Each dimension has 3 levels indicating no problems, some problems or extreme problems. The index values on a scale between -1 (low) and 1 (high) are showing the average health status according to the 5 dimensions: A low score shows worse health and a high score shows better health. With the EQ VAS the respondents can report their perceived health status with a grade ranging from 0 (the worst possible health status) to 100 (the best possible health status).
Investigation of Patient Outcome With Radiographic Analysis	3 months, 1, 2, 5, 7 and 10 years	Plain radiographs will be obtained for assessment of fixation of the device.
Investigation of Clinical Performance and Patient Outcome With the Knee Injury and Osteoarthritis Outcome Score (KOOS) Patient Questionnaire	pre-operative, 3 months, 1, 2, 5, 7 and 10 years	KOOS consists of 5 subscales: Pain, other symptoms, function in daily living , function in sport and recreation and knee related quality of life (QOL). The previous week is the time period considered when answering the questions. Standardized answer options are given (5 Likert boxes) and each question is assigned a score from 0 to 4. A normalized score (100 indicating no problems or a better outcome and 0 indicating extreme problems or a worse outcome).