Evidence-based evaluation

Objectively examining the short and longer-term clinical effects of the GenuTrain OA knee brace – that is the main objective of the current study conducted by the Institute of Sports and Sports Science at KIT in Karlsruhe, Germany. It is based on detailed biomechanical and functional analyses that demonstrate strain conditions acting on the knee joint – supplemented by information provided by the participants about pain perception and activity.

In the middle of 2021, a study assessing Bauerfeind’s ­GenuTrain OA knee brace started at the Institute of Sports and Sports Science at Karlsruhe Institute of Technology (KIT). The prospective, controlled, randomized study in which the patient groups wearing the medical aid were observed on different occasions, followed clearly defined specifications: “The objective of our study is to get evidence-based research findings regarding the effects of the GenuTrain OA that can be included in the guidelines for treating osteoarthritis of the knee in the long term,” explain the study directors, Prof. Dr. Stefan Sell and Dr. Bernd Stetter. “In addition, we want to use the GenuTrain OA to generate objective evidence for options for treating osteoarthritis of the knee in the mid-range, i.e. between a lightweight support and a rigid brace, for an active, sporty target group, in particular. They can use the BoaFit® system to individually adjust the degree of relief themselves, which has a huge impact on compliance.”

Comprehensive analyses

A study design with different measurement methods was chosen to precisely record the effects of the GenuTrain OA in the active everyday life of the subjects. “The study includes two tests at baseline and a six-week intervention phase at the end, which provides us with short and longer-term analyses of the effects. We will take into account biomechanical and functional aspects as well as effects relating to activity and pain perception,” Dr. Bernd Stetter explains. For the biomechanical assessment, three-dimensional gait analyses are carried out, for example, when walking in a straight line on even ground, during moderate jogging and climbing the stairs. A motion capture procedure is used that works with infrared rays and reflecting markers that are stuck on the subjects. In connection with force plates in the floor, joint kinematics and joint dynamics can be determined. Using biomechanical modeling, central strain indicators, such as medial and lateral contact forces in the knee joint, as well as the knee adduction torque can be identified.

A functional analysis records possible effects of the GenuTrain OA on knee functioning in a 6-minute walk test. In addition, a mobile sensor worn on the belt measures the activity level of the participants during everyday life. Pain perception is also analyzed during the walk test. The subjects additionally use a diary to document pain at rest, at night and during activity. A knee stability questionnaire, the Knee Osteoarthritis Outcome Score (KOOS), supplements the data collection. “The study is very comprehensive and strictly controlled, in terms of time as well as examination methods,” highlights Dr. Bernd Stetter.

Definitive feedback

The study includes 24 subjects of both genders. The inclusion criteria specified that participants should be between the ages of 45 and 75, have a sporty, active BMI of below 35 and moderate unilateral¹ medial osteoarthritis of the knee confirmed by radiographic imaging. “People with moderate osteoarthritis of the knee are particularly interesting to us because we can treat them the longest without surgery,” explains Prof. Dr. Stefan Sell. As of April 2022, half of the 24 subjects have already completed the entire six-week intervention phase, including all measurement visits and movement tasks. And what is the participants’ feedback?

“For them, the biggest plus is the brace’s high level of wearing comfort. They can wear the brace for extended periods and don’t perceive it as restrictive. Of course, this doesn’t apply to every single subject, but for the majority, the effect and benefits of the GenuTrain OA perfectly meet their demands and needs,” Dr. Bernd Stetter reports. “None of the subjects had to cut back on their sporting activities during the six-week test phase, which is very important when treating osteoarthritis of the knee,” Prof. Dr. Stefan Sell adds. “This makes the GenuTrain OA perfect for maintaining the activity level of sporty patients with osteoarthritis of the knee.”

Promising insights

From a scientific perspective, the emerging measurement results are also very promising: “In particular the biomechanical analysis using complex measurement technology allows us look into the body, if you will, and the subsequent computer-based modeling enable us to calculate specific joint strain levels,” says Dr. Bernd Stetter. “This data is very meaningful and exactly shows the forces acting on the joint. It also demonstrates to what extent it’s objectively possible to reduce strain in the medial compartment using a brace. We are very confident that we will be able generate the evidence to confirm the effects of the GenuTrain OA with our measurements,” the two study directors conclude. “The findings can contribute to realizing the vision in treating osteoarthritis of the knee – using appropriate relief in cases of moderate osteoarthritis of the knee to positively impact its progression and reduce the need for surgery – and all that practically without any side effects, thanks to the brace.”

1 People with bilateral osteoarthritis of the knee were accepted if their Kellgren Lawrence Score was ≤ 1 on one side and there has not been any knee pain in the previous 3 months.

Images: Udo Schönewald