Joint Loading & Musculoskeletal Analysis

The loads acting in joint prostheses and other orthopaedic implants is still partially unknown. The acting loads are required for different purposes.

You are here:

Dr. rer. medic. Adam Trepczynski

Postdoctoral Reearcher - Musculoskeletal Analysis

Musculoskeletal Modelling

We use musculoskeletal modeling to explain and analyze the forces and interaction within the musculoskeletal system.

Musculoskeletal computer models apply mechanical principles to a system composed of bones, muscles and ligaments in order to estimate internal loading conditions. The models use limited information available from direct measurements of movement and external forces to estimate quantities that cannot be easily measured in vivo, like joint contact and muscle forces. This significantly extends the possibilities to analyze the influence of external and internal factors on the dynamic internal loading of the anatomic structures. The obtained internal loading information can be utilized to perform further detailed analyses of the loading distribution within individual anatomical structures like bones. The models require validation against joint contact forces measured in vivo in a limited set of patients with instrumented joint implants. EMG measurements of muscle activity can be used as an additional mean of validation or as input for the models.

From a history of expertise in understanding the internal loading conditions present in the musculoskeletal structures of the human body, the Musculoskeletal Biomechanics group is able to determine how muscles and the specific anatomy of the lower limb interact to define the internal loads. Our group was the first to demonstrate that the musculoskeletal loading conditions could be predicted using computer modelling techniques and has directly validated these results against forces measured in vivo [1]. Our research has also developed an improved understanding of musculoskeletal motion at both the organ and limb levels. Specifically, we are able to measure whole body motion using motion capture systems, together with new approaches to deal with soft tissue artefacts [2], which are crucial for accurate musculoskeletal models.

Our computational models also allow for quantification of dynamic loading conditions at the patello-femoral joint, which show that the patella-femoral contact force can reach levels of more than three times bodyweight during daily activities of daily living [3]. Further, we have investigated the relationship between internal loading at the knee and external knee moments, which are widely used as a proxy measure for the internal loads. Here we were able to show that this often assumed relationship is present, but also highly subject-specific [4, 5].

As part of the OVERLOAD-PrevOp network, we are currently investigating the impact of training methods on osteoarthritis progression in patients with an anterior cruciate ligament rupture. In order to determine detailed cartilage loading in those patients, we are combining our musculoskeletal computer modeling expertise with efficient finite element methods developed by our cooperation partners at the Zuse Institute Berlin (ZIB).

Muskeloberflächen extrahiert aus dem Visible Human Datensatz (Philippe Moewis et al.)
Muskel-Zentroidlinen auf spezifisches Subjekt übertragen (Philippe Moewis, Adam Trepczynski et al.)
Skelettale Kinematik bestimmt durch fitten der spezifischen Anatomie an funktionelle Gelenk-Zentren/Achsen aus Bewegung reflektierender Hautmarker (Adam Trepczynski et al.)

Feaured Publications

  • Trepczynski A, Kutzner I, Schutz P, Dymke J, List R, von Roth P, Moewis P, Bergmann G, Taylor WR, Duda GN

    Tibio-Femoral Contact Force Distribution is Not the Only Factor Governing Pivot Location after Total Knee Arthroplasty


    Total knee arthroplasty aims to mimic the natural knee kinematics by optimizing implant geometry, but it is not clear how loading relates to tibio-femoral anterior-posterior translation or internal-external pivoting. Tibio-femoral loading was measured using an instrumented tibial component in six total knee arthroplasty patients (aged 65-80y, 5-7y post-op) during 5-6 squat repetitions, while knee kinematics were captured using a mobile video-fluoroscope. In the range of congruent tibio-femoral contact the medial femoral condyle remained approximately static while the lateral condyle translated posteriorly by 4.1 mm (median). Beyond the congruent range, the medial and lateral condyle motions both abruptly changed to anterior sliding by 4.6 mm, and 2.6 mm respectively. On average, both the axial loading and pivot position were more medial near extension, and transferred to the lateral side in flexion. However, no consistent relationship between pivoting and load distribution was found across all patients throughout flexion, with R(2) values ranging from 0.00 to 0.65. Tibio-femoral kinematics is not related to the load distribution alone: medial loading of the knee does not necessarily imply a medial pivot location.

    Sci Rep 2019; 9(1):182.

  • Trepczynski A, Kutzner I, Schwachmeyer V, Heller MO, Pfitzner T, Duda GN

    Impact of antagonistic muscle co-contraction on in vivo knee contact forces


    BACKGROUND: The onset and progression of osteoarthritis, but also the wear and loosening of the components of an artificial joint, are commonly associated with mechanical overloading. Mechanical forces acting at the joints and understanding of the key factors that can alter them are critical to develop effective treatments for restoring joint function. While static anatomy is usually the clinical focus, less is known about the impact of dynamic factors, such as individual muscle recruitment, on joint contact forces. CONCLUSIONS: Treatment of diseased and failed joints should not only be restricted to anatomical reconstruction of static limb axes alignment. The dynamic activation of muscles, as a key modifier of lower limb biomechanics, should also be taken into account and thus also represents a promising target for restoring function, patient mobility, and preventing future joint failure. German Clinical Trials Register: ID: DRKS00000606

    J Neuroeng Rehabil 2018; 15(1):101.


Publications

Results 1 to 10 of total 20


Results 1 to 10 of total 20