3D Motion Analysis: Postural patterns in patients with hemophilia

Joint and muscle bleeds are common problems in people with hemophilia. A study used 3D motion analysis to research joint changes and their impact on patterns of walking and posture.

In this MEDICA-tradefair.com interview, Dr. Fabian Tomschi and Prof. Thomas Hilberg explain how the technology calculates a representation of the posture and reveal how this facilitates a detailed analysis.

What does the research project on posture analysis in people with hemophilia involve?

Dr. F. Tomschi, Prof. T. Hilberg: As part of our study, which was a project collaboration between the Chair of Sports Medicine at the University of Wuppertal and the Department of Orthopedics and Trauma Surgery at the University Hospital in Bonn, 40 patients with hemophilia and 40 healthy controls took a treadmill stress test at a constant speed. We used state-of-the-art technologies such as video raster stereography and pedobarography to study the postural and gait patterns, and pronation (movement of the foot that occurs during foot landing) of the feet. The research delivered profound insights into the impact of hemophilic arthropathy on physical movement and the correlated postural and gait problems. Hemophilic arthropathy is a complication of joint bleeds in people with bleeding disorders such as hemophilia. This progressive change leads to marked degeneration of the joints. Video raster stereography and pedobarography help detect early changes, analyze patterns of compensation, and assist the development of targeted therapies.

How does the posture analysis process work?

Tomschi, Hilberg: The process focuses on the accurate measuring of the mechanics of the spine and feet. To get an objective and unbiased representation of the surface topography of the back and the foot pressure, the study participants are asked to walk barefoot on the treadmill in their underwear. This approach enables us to get a precise foot movement analysis, to measure specific pressure distributions for individual areas of the foot, and to identify deviations from normal foot mechanics. Reflective markers are placed on precisely defined anatomical landmarks on the back to assess the biomechanics of the spine. The system uses cameras to accurately detect changes in the movement of the spine during dynamic motion, in this case while the person is walking. The technology uses triangulation to calculate a representation of the posture, thus enabling a detailed postural analysis of the participant.

What intermediate results were you able to gain by using the 3D motion analysis method?

Tomschi, Hilberg: Pertaining to statics, patients with hemophilia merely exhibited significantly higher pelvic torsion. No differences were measurable in the foot mechanics from a static perspective.

The dynamic analysis was a different story: Here, we detected a greater forward trunk tilt and pelvic torsion as well as a loss of lumbar lordosis in the patients with hemophilia. These findings highlight the unique challenges that people with hemophilia face in maintaining postural stability and control of balance during walking.

We also detected changes in the pressure distribution of foot pronation in people with hemophilia. Compared to healthy controls, we measured significant differences in the metatarsal and heel. These findings help us gain a better understanding of the foot biomechanics in people with hemophilia and can support the development of new therapeutic approaches.

How does the joint situation affect the gait pattern in people with hemophilia?

Tomschi, Hilberg: People with severely affected ankle joints - meaning people suffering from advanced hemophilic arthropathy - exhibited decreased step length and stride time and increased stride frequency. These findings are very significant since they demonstrate that people with hemophilia not only have difficulties with posture and foot pronation but are also restricted in general movement ability.

What’s interesting is that the findings showed no significant correlations between spinal parameters and current pain intensity (assessed based on the visual analog scale, VAS) despite measurement of subjective pain in the subjects with hemophilia. This suggests that other factors, such as poor joint conditions, have a greater impact on posture than pain.

These results are very important because they show that not only pain but also other factors, such as structural joint damage, may be key drivers affecting postural changes in people with hemophilia. This means a posture analysis of people with hemophilia also requires a detailed and careful analysis of the joint situation.

Which research findings can be transferred into practice?

Tomschi, Hilberg: Understanding pressure-related changes in the feet is a promising way of avoiding or at least reducing peak pressure. One way to do this is using custom feet insoles to prevent overstressing of structures. That being said, the transfer of pedobarographic data into an optimized therapy needs further research to facilitate a better assessment of other effects on the feet, the kinetic chain, and the spine structure.

The adaptive posture observed in people with hemophilia caused by the adverse joint situation seems necessary to maintain balance and a healthy normal walking pattern. Patients might also benefit from regular targeted strength and coordination exercises that help improve posture. It is important to point out that a posture change not only affects the physical but also the psychological well-being and can impact the quality of life of patients with hemophilia. That is why any treatment should also include therapeutic exercises to help improve posture.

The findings of the study emphasize the importance of a holistic perspective of posture as it pertains to people with hemophilia. Video raster stereography and pedobarography can provide valuable data and information. Research in this area should be strongly encouraged to guarantee the best possible care for those affected and help improve or maintain their health and quality of life.