MECHANICAL LINKS

Mechanical osteopathic link is a trend in osteopathy that was elaborated by French osteopath Paul Shauffour. It embraces more than 400 motional tests estimating the mobility of joints, viscera, cranium, skin and nerves. It involves detecting of the main or dominant dysfunction and effecting on the given lesion by means of gentle manual technique Recoil.

Recoil is characterized by a brief enchantment of dysfunction and a sharp removal of pressure. Follow-on testing shows that the pattern of movement constraints changes and, as a rule, points to the direction of the second additional influence. The effect of the first and the second influence on vegetative nervous system was investigated by means of estimating variability of heart rate.

Variability of heart rate
Variability of heart rate reflects with high precision the state of regulatory processes. Variability of heart rate is a set of characteristics from variability of instantaneous heart rate period to its causes determined and defined by nonlinearity of sympathetic, parasympathetic and humoral regulation,  by their branched interrelations and relations with infracortical, subcortical and cortical formations, as well as by responses to mental, physical stresses and other types of stresses.

Spectrum analysis implies using R-R intervals of electrocardiogram as a periodic function in Fourier transform algorithm and obtaining frequency spectra with different density. In spectral decomposition of daily ECG we can distinguish 4 characteristic zones of amplitude rise (Malliani A., 1998; Yavelov I.S. et al., 1999). Investigation of the three zones is of clinical value.

Very Low Frequency (VLF) – the zone of very low frequency (0,0033 – 0,05 Hz)

Low Frequency (LF) – the zone of low frequency (0,05 – 0,15 Hz)

High Frequency (HF) – the zone of high frequency (0,15 – 0,5 Hz)

Standard VLF amounts 15 – 30 % of oscillation spectrum total power (TP). Decrease of VLF mirrors energy deficient state, while increase of VLF indicates hyper adaptation (Bayevsky R.M. et al., 2001).

Standard LF permits to estimate sympathetic activity in heart rate regulation (Bayevsky R.M. et al., 2001). It’s supposed that LF power is connected with humoral circuit of regulation (Bayevsky R.M., Motylyanskaya R.E., 1986).

Standard HF characterizes activity of parasympathetic part of vegetative nervous system (Bayevsky R.M. et al., 2001). Respiratory center substantially influences HF power. Direct subordination of respiratory center to cortical functions mediates direct central influences on heart rate (Malik M., 1996; Cooley R.L. et al., 1998).

TP (total power) characterizes total power of oscillation spectrum and, being a sum of VLF, LF and HF, reflects the activity of vegetative nervous system (Bayevsky R.M. et al., 2001).

It’s been shown that 1 minute-long recording is sufficient for analyzing of high frequency part of spectrum and 2 minute-long recording is sufficient for analyzing of low frequency part of spectrum (Makarov L.M., 2000; Tarsky N.A. et al., 2000; Mortara A et al., 1996).

LF/HF ratio indicates the balance of sympathetic and parasympathetic parts of vegetative nervous system and reflects the type of vegetative regulation (Malik M., CammJ., 1993). Index LF/HF equal to 0,5 – 2 indicates amphotony (figure 4), index LF/HF > 2,0 indicates sympathicotony (figure 5), index LF/HF < 0,5 indicates vagotony.

Heart rhythm variability allows evaluating activity of autonomic nervous system (Pomeranz B. et al., 1985; Pichot V. et al., 1999).

Spectral analysis allows estimating calculated indexes as well. Those are index centralization (IC = (VLF + LF)/HF) and subcortical nervous center activity index (SNCA = LF/VLF). IC reflects central and autonomic circuit of heart rhythm regulation ratio and increases in case of autonomic regulation impairment (Aksyonova A.M. et al., 1997). SNCA reflects the state of cardiovascular center of brain and allows estimating baroreflex efficiency (Rogoza A.N. et al., 2000). IC and SNCA decrease may indicate the normalization of regulatory processes performed by vegetative nervous system (Aksyonova A.M. et al., 1997)

The purpose of this investigation was to find out the character of osteopathic effect on HRV indexes.

Patient population
The study involved 35 people (8 males and 27 females), of average age of 26,5. In accordance with LF/HF ratio value (index Malik) the patient population was divided into groups according to the type of vegetative regulation (figure 1). The first group was formed by patients with amphotony (LF/HF = 0,97) – 20 people (4 males and 16 females), the second one – by patients with sympathicotony (LF/HF = 3,44) – 6 people (all females), the third group – by patients with vagotony (LF/HF = 0,3) – 9 people (4 males and 5 females).

Figure 1 – distribution of patient population according to the types of vegetative regulation

Methods of study
HRV had been registered at the apparatus Poly-Spectr (“NeuroSoft”, Ivanovo) during 5 minutes before and after osteopathic manipulations.

Results of study
The heart rate of patients with vagotony was lower (60,8 per min) than of those with amphotony (73,1 per min) and of those with sympathicotony (74 per min) (figure 2). It was observed that after osteopathic influence heart rate of patients in all three groups tended to slow down (p>0,05).

Figure 2 Influence of osteopathic manipulations on heart rate in patients with different types of vegetative regulation

Table 1
Influence of osteopathic manipulations on sympathovagal balance parameters in people with different types of vegetative regulation

Analysis of the effects osteopathic manipulations have on the main index (LF/HF) of vegetative nervous system balance showed that three groups under investigation differ in dynamics of this index (table 1). Manipulations applied didn’t change virtually the value of LF/HF ratio in patients with amphotony (reference value – 0,97, afterwards – 0,84 and 0,87 - after the first and the second manipulations accordingly), for there’s no significant difference between these two values (p<0,05) (figure 3).  The first manipulation caused a sharp decrease of LF/HF value in patients with sympathicotony (reference value – 3,44, afterwards – 1,28, p=0,002), at the same time the value of low-frequency power of RR-interval duration spectrum component, as well as the value its high-frequency component increased (from 195,3 to 417,8 ms2 and from 61,9 to 878,7 ms2 accordingly) (table 2). But since the increase of HF was of the higher-order, LF/HF index decreased. The second manipulation hadn’t caused any significant change in Malik index (from 1,28 afterwards 1 to 1,62 afterwards 2, p=0,01) but there was no return to the reference level (reference value - 3,44 and 1,62 afterwards 2, p>0,005). Two osteopathic manipulations caused the increase of value LF/HF in patients with vagotony (from reference value of 0,3 to 0,67 and then to 0,96, p=0,05) (figure 3). It should be noted that in this group low-frequency power spectrum component moderately increased (from 973,3 to 190 and than to 1232,9 ms2) but increase of Malik index occurred because of evident decrease in high-frequency spectrum component (from 3323,6 to 2001,2 and than to 2230,4 ms2) (table 2).

Figure 3. Effect of osteopathic manipulations on the vegetative nervous system parts balance index (LF/HF) in patients with different types of vegetative regulation

Total power of RR-interval duration spectrum (TP) was a maximum in patients with vagatony (5235,7 ms2) and a minimum in patients with symathicotony (633,3 ms2) (table 2). Osteopathic correction had a different effect on TP in three groups under investigation. In people with amphotony TP increased after the first manipulation (from 3346,2 to 3757,8 ms2) and came back to the value indistinguishable from the reference one after the second manipulation. In patients with sympathicotony the increase in TP was more substantial after the first manipulation (from 633,3 to 1631,2 ms2), and after the second manipulation decreased to 961 ms2 without having reached the background level. In contrast to the dynamics of this index in first two groups under investigation, in case of vagotony after the first manipulation decrease in TP was observed (from 5235,7 to 4017,3 ms2) and after the second manipulation increase took place in TP exceeding the reference level (5471,3 ms2).

Table 2
Influence of osteopathic manipulations on centralization index and subcortical nervous regulation centers activity index in patients with different types of vegetative regulation

Centralization index was optimal in people with amphotony (1,71) (figure 4). In the course of osteopathic correction it oscillated temperately: first it decreased to 1,08, later on it increased to 1,41, though it haven’t reached the reference level (1,41). In case of sympathicotony distinctly decreased IC substantially went down after the first manipulation (0,86), and after the second one it increased 1,7 times more, without having reached the reference level (1,42). In patients with vagotony IC increased steadily in the process of osteopathic manipulations (from 0,60 to 1,0 and than to 1,45)

Figure 4. Influence of osteopathic manipulation on centralization index in patients with different types of vegetative regulation

The activity of subcortical centers on the reference level was different in the three groups under investigation: the lowest SNCA was in case of sympathicotony (0,52) as compared with amphotony (1,04) and vagotony (0,96). Under osteopathic manipulation SNCA dynamics differed substantially depending on the types of vegetative regulation. In patients with amphotony a temperate increase of SNCA was marked (from 1,04 to 1,18 and than to 1,49). In case of sympathicotony SNCA had been increasing at first from 0,52 to 1,25 and than decreasing to 0,85. In patients with vagotony the first influence increased SNCA after from 0,96 to 1,78, and after the second one decreased to 0,61 that was 36,5 % lower than the reference value.

Figure 5 Influence of osteopathic manipulations on subcortical nervous regulation centers activity index in patients with different vegetative status.

Thus, the use of osteopathic manipulations has indubitable influence on the mechanisms of vegetative regulation of the cardiovascular system main indexes, optimizing them.