Biomechanische determinanten en patronen geassocieerd aan de pathophysiologische enkelarthropathie cascade van kinderen met haemophilie.

Haemophilia is a X chromosome-linked coagulation disorder resulting from a congenital deficiency or absence of circulating factor VIII or factor IX. Patients with haemophilia are unable to generate adequate thrombin resulting in abnormal bleeding. Approximately 80-90% of bleeding episodes occur in the musculoskeletal system, especially in the large synovial joints and muscles. Repeated haemarthrosis induces joint cartilage damage and irreversible degenerative joint disease. Primary prophylaxis is the evidence-based, first-choice treatment in children with severe haemophilia. This has radically decreased the incidence of arthropathy in patients with haemophilia; however, the ankle joint seems to be an exception to the rule, as patients treated with primary prophylaxis still experience ankle arthropathy. As such, the ankle is the main affected joint in patients with haemophilia under the age of 20.

In this research project, we aimed at determining aetiologic/contributing factors associated to the ankle arthropathy pathophysiological cascade in children with haemophilia (CwH).

In the first stage of the project, we developed a  3D MultiSegment Foot Kinetic Model (3DMFKM) which allows the estimation of foot joints kinetics in-vivo. Challenges which had to be overcome in this perspective was the definition of joint centres, calculation of segment inertial properties and the precise measurement of the total ground reaction force (tGRF) in different foot regions. Once the development of the 3DMFKM was successfull, implementation in an advanced clinical examination platform (ACEP) was performed. The latter platform allows an integrated measurement and processing of biomechanical signals including EMG, ground reaction forces and 3D motion.

In a second stage, the ACEP was used to gain insight into the aetiologic/contributing factors associated to the ankle arthropathy pathophysiological cascade in children with haemophilia (CwH). A number of outcome measures have already been published in the scientific peer-reviewed literature.

• Deficits of ankle muscle strength not found in children, adolescents and young adults with haemophilic ankle arthropathy. Lobet S, Croisier JL, Lantin AC, Hermans C, Peerlinck K, Vandesande J, Pialat JB, Deschamps K. Haemophilia. 2017 Jul 9. doi: 10.1111/hae.13274.

• Biomechanical markers and theoretical concepts related to haemophilic ankle and subtalar joint arthropathy: introducing the term 'haemophilic tarsal pan-arthropathy'. Lobet S, McCarthy A, Hermans C, Peerlinck K, Matricali GA, Staes F, Deschamps K. Haemophilia. 2017 Mar 17. doi: 10.1111/hae.13202. [Epub ahead of print] Review.
• 3D Multi-segment foot kinematics in children: A developmental study in typically developing boys. Deschamps K, Staes F, Peerlinck K, Van Geet C, Hermans C, Matricali GA, Lobet S. Gait Posture. 2017 Feb;52:40-44. doi: 10.1016/j.gaitpost.2016.11.022. Epub 2016 Nov 11.

• Postural control of typical developing boys during the transition from double-leg stance to single-leg stance. Deschamps K, Staes F, Peerlinck K, Van Geet K, Hermans C, Lobet S. Eur J Pediatr. 2017 Mar;176(3):429. doi: 10.1007/s00431-017-2863-6. No abstract available.