Previous cervical traction studies have investigated the impact of traction force intensity and duration of traction force on outcomes of cervical traction therapy.

Objective: The present study aims to demonstrate the impact of the intensity of the traction force and the time of the rise of this force on the measurement of separation during cervical spine traction.

the human cervical spine was modeled as a system with eight degrees of freedom, an undamped system subjected, first of all, to a force of rectangular impulse then to a force of progressive intensity (sloping). The equations of motion describing this model were written and then solved using modal analysis. The intensity of the traction force and the time rise of the force were gradually modified in order to verify their impact on the evolution of the increase in intervertebral spaces.

the numerical results showed that the intervertebral spaces calculated using different increments of the rise time (1'', 5'', 10'', 15'' and more) do not differ much and this remains proportional to the gradual increase in the tensile force applied (100N , 150N , 200N). A gradual increase in the intervertebral spaces has also been observed, these spaces being all the higher as the tensile force is greater.

The influence of the intensity of the pulling force on the intervertebral space is studied for 𝐹 0 = 100 𝑁 ,150 𝑁 and 200 𝑁 and the influence of the time of the rise is studied first for a rectangular impulse, then for a pulse with linear transition (T 0 = 1  , 5 𝑠 , 10 And > 10 𝑠) . Tables 3, 4 and 5 show the simulation results. As we can see :
1 Each intervertebral space increases proportionally with 𝐹 0, this offers the possibility of a gradual readjustment of the traction force for a progressive tolerance in case of intolerance. This result was observed during in vitro experimentation in goats [10].

With regard to the result observed during the variation of the time of the ascent whatever the intensity of the traction load, we can argue that the duration of a cervical traction session can be revised downwards, because this it does not influence the variation of the intervertebral spaces in a significant way. The in vitro experiment in goats confirmed this study when it specified that beyond 5 minutes no increase in gain on the intervertebral spaces was observed (10).

This study confirms the need to monitor the speed of deployment of the traction force (rise time) as well as the progressive evolution of the widening of the intervertebral spaces, proportional to the traction force applied. However, it emphasizes that the time variation of the climb has almost no influence on the gain in intervertebral space. Hence the need on the one hand to monitor the speed of execution of the cervical traction to avoid damage to the anatomo- physiological structures.

[1]BI Woods, AS Hilibrand "Cervical radioculopathy ", journal of Spinal Disorders Techniques , vol. 28, no. 5 , pages E251-E259, 2015.
[3]S. Carette and MG Fehlings , "Cervical radiculopathy ", New England Journal of Medicine , vol. 353, no. 4 , p. 392, 2005.
[10]George Meya Kiala , Nsitwayizatadi B, Nzinga Luzolo AM, Miangindula B, Nkakudulu BH, Mbuyi Muamba JM, " Threshold of deformation of the structures of the cervical spine of goats . In vitro experimentation." ISCOS Congress Journal Vancouver, Canada 2022.