Weight Loss Intervention Before Total Knee Replacement

NCT ID: NCT01469403

Last Updated: 2015-03-17

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 76 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2011-08-31
• Study Completion Date: 2014-06-30

Brief Summary

The purpose of this study is to compare the efficacy in a group of patients who must follow the current procedure for treatment of artificial knee, compared with a group of patients who must undergo an 8-week weight loss program before surgery. 1 year after surgery the investigators will examine whether there are differences between the two groups' quality of life and functional capacity.

Detailed Description

Background In Denmark the numbers of primary total knee arthroplasty (TKA) operations annually increase. In the year 2000 was performed approximately 2,500 operations and in 2008 was performed more than 7,500 total knee arthroplasty operations, and there appears in all countries to be similar tendency. Meanwhile, the prevalence of overweight and obesity has increased markedly over the last 50 years. Approximately 13% of the Danish population is obese. For several years the association between obesity and knee osteoarthritis (OA) has been recognized, and osteoarthritis is the most frequent indication for total knee arthroplasty(80%).

The purpose of this study is to investigate whether weight loss interventions before primary total knee arthroplasty will improve quality of life and functional level, reduce pain and risk of early and late postoperative complications.

Sample size Significance level is set to 5% by using a 2-sided analysis and the power is set at 80%. Based on an expectation of a difference in patient-reported outcome scores in between the groups at 8%, as measured by SF-36 12 months postoperatively, standard deviation (SD) 13 must be include 41 participants in each group. To allow a drop-out rate of 20% the group size increases to 51 participants in each group. In total 102 participants.

Statistical analysis, The two groups scores at 12 months postoperatively, and the two groups' change in the primary outcome measurer, from 1 week before surgery to 12 months postoperatively, compared with t-test or Mann-Whitney test rang sum depending on data distribution.

Conditions

Osteoarthritis, Knee; Obesity

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: SUPPORTIVE_CARE
• Blinding Strategy: SINGLE

Study Groups

control group

Standard procedure for knee arthroplasty

Group Type: NO_INTERVENTION

No interventions assigned to this group

Weight loss program

The intervention program consists of 8 weeks of low-diet, using formula foods, and dietary counseling before surgery. When using formula foods the patients can achieve a quicker weight reduction and a greater reduction in fat mass than using conventional dietetic hypo caloric diet.

Group Type: ACTIVE_COMPARATOR

8 weeks weight loss program, Cambridge.

Intervention Type: BEHAVIORAL

Fast weight losses improve the prognosis for the sustained weight loss. During the first week a dietitian will tutor the participants in formula food diet (The Cambridge Health and Weight plan UK.), followed by seven weeks with control guidance and instruction in healthy eating habits once a week. The guidance by the dietitian will be carried out both on an individual basis and in groups. The goal of the intervention is to achieve a preoperative weight loss of at least 5 to 10% of the patient's body weight, thus improving patient's health before surgery.

Interventions

8 weeks weight loss program, Cambridge.

Fast weight losses improve the prognosis for the sustained weight loss. During the first week a dietitian will tutor the participants in formula food diet (The Cambridge Health and Weight plan UK.), followed by seven weeks with control guidance and instruction in healthy eating habits once a week. The guidance by the dietitian will be carried out both on an individual basis and in groups. The goal of the intervention is to achieve a preoperative weight loss of at least 5 to 10% of the patient's body weight, thus improving patient's health before surgery.

Intervention Type: BEHAVIORAL

Eligibility Criteria

Inclusion Criteria

• All patients recommended for primary total knee replacement.
• Body mass index > 30.
• Must be motivated for weight loss.
• Must be able to read and understand Danish.

Exclusion Criteria

• Rheumatoid arthritis.
• Patients who are operated on both knees during the project period can only participate once.
• Planned obesity surgery.

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

The Danish Rheumatism Association

OTHER

Sponsor Role: collaborator

Cambridge Weight Plan Limited

INDUSTRY

Sponsor Role: collaborator

University of Aarhus

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Kjeld Søballe, Prof. D.Msc

Role: PRINCIPAL_INVESTIGATOR

Department of Orthopedics Research Aarhus University Hospital

Locations

Department of Orthopedics Research Aarhus University Hospital

Aarhus, , Denmark

Countries

Denmark

Other Identifiers

TKABMI

Identifier Type: -

Identifier Source: org_study_id