Studie som bekrefter alt om diafragma og dens bevegelse. Bl.a. at den har mye mev holdning og bevegelse å gjøre, og at baksiden beveger seg mest. Nevner også hva som er optimal bevegelse av diafragma for best fungere som stabilisator av ryggraden i bevegelse.

http://www.plosone.org/article/info:doi/10.1371/journal.pone.0056724

When a load was applied to the lower limbs, the pathological subjects were mostly not able to maintain the respiratory diaphragm function, which was lowered significantly. Subjects from the control group showed more stable parameters of both respiratory and postural function. Our findings consistently affirmed worse muscle cooperation in the low back pain population subgroup

The diaphragm and deep stabilization muscles of the body have been described as an important functional unit for dynamic spinal stabilization [1], [2]. The diaphragm precedes any movement of the body by lowering and subsequently establishing abdominal pressure which helps to stabilize the lumbar part of the spine. Proper activation of the diaphragm within the stabilization mechanism requires the lower ribs to be in an expiratory (low) position. During the breathing cycle, the lower ribs have to stay in the expiratory position and only expand to the sides. This is an important assumption for the straight and stabilized spine. Under these conditions, the motion of the diaphragm during respiration is smooth, and properly helps to maintain abdominal pressure.

Dysfunction of the cooperation among diaphragm, abdominal muscles, pelvic floor muscles and the deep back muscles is the main cause of vertebrogenic diseases and structural spine findings such as hernia, spondylosis and spondylarthrosis [3], [4].

Noen studier å se nærmere på her:
Studies focused on diaphragm activation with the aim of posture stabilization include Hodges[11]–[14], who concluded phase modulation corresponding to the movement of the upper limbs in diaphragm electromyography records. Some works deal with various modes of diaphragm functions in various respiration types [15], [16] or in situations not directly related to respiration, e.g. activation during breath holding [17]. These studies have always concentrated on healthy subjects who did not exhibit symptoms of respiratory disease or vertebrogenic problems.

Og enda fler å se nærmere på her, spesielt relatert til scoliose:
Gierada [20] also used MRI for observing the anteroposterior size of the thorax, the height of the diaphragm during inspiration and expiration, and also the ventral and dorsal costophrenic angle during maximal breathe in and out. Kotani[21] and Chu [22] assessed chest and diaphragm movements for scoliosis patients. Suga [23]compared healthy subjects and subjects with chronic obstructive pulmonary disease (COPD), measuring the height, excursions and antero-posterior (AP) size of the diaphragm with the zone of apposition. Paradox diaphragm movements for subjects with COPD were investigated by Iwasawa [10]. Iwasawa used deep breath sequences while comparing diaphragm height and costophrenic angles. The study consisted of healthy subjects and subjects with scoliosis. Kotani [21] concluded that there was ordinary diaphragm motion with limited rib cage motion in the scoliosis group. The position of the diaphragm was measured relative to the apex of the lungs to the highest point of the diaphragm. Chu [22] compared healthy subjects against subjects with scoliosis, finding the same amount of diaphragm movement for both groups. The scoliosis group had the diaphragm significantly lower in the trunk and relatively smaller lung volumes. The distance between the apex of the lungs and the diaphragm ligaments was measured by Kondo [24], comparing young and old subjects. The effect of intraabdominal pressure on the lumbar part of the spine was observed by MRI and pressure measurement by Daggfeldt and Thorstensson [25]. Differences in diaphragm movement while performing thoracic or pulmonary breathing with the same spirometric parameters were tested by Plathow[26]. Plathow also examined the vital capacity of the lungs compared with 2D and 3D views in[27]. He concluded that there was a better correlation between the lung capacity and the 3D scans. In another study, Plathow focused on dynamic MRI. He proved significant correlations among diaphragm length and spirometric values vital capacity (VC), forced expiratory volume (FEV1) and other lung parameters [28].

Nevner også hvordan MRI-funn i ryggraden ikke har noe med smerte å gjøre:
Jensen found no direct connection between certain types of structural changes and LBP. The only structural change related to pain was disk protrusion. Carragee [31] studied MRI findings of 200 subjects after a period of low LBP, and found no direct significant MRI finding related to low back pain.

Nevner at problemer med pustefunksjon kan være en større indikator på ryggsmerter enn forandringer i ryggsøylen:
The way in which the diaphragm is used for non-breathing purposes is affected by it’s recruitment for respiration [32]. There is evidence that the presence of respiratory disease is a stronger predictor for low back pain than other established factors [33]. However, the relationship between the respiratory function and the postural function is widely disregarded[34]. Body muscles coordination for posture stabilization is a complex issue, and the role of the diaphragm in this cooperation has not been intensively studied [35].

Målet med studien:
he main goal is to separate respiratory diaphragm movements from non-respiratory diaphragm movements, and then to evaluate their role in body stabilization.
We investigated diaphragm reactability and movement during tidal breathing and breathing while a load was applied to the lower limbs.

Eksempel på diafragmas bevegelse:

Viser normal(C2) reaksjon på aktivitet(S2) og forskjellen i unormal(C1) reaksjon ved rygglager:

Figure 4. Dif-curves (solid line) and extracted res-curves (red dashed line) and pos-curves (green dotted line).

Example of harmonic breathing (A), breath with a strong postural part after the load occurred (B), harmonic breath which became partly non-harmonic after the load occurred (C, D), and breath which almost lost its ability of respiration movement ability after the load occurred (E, F).

Om hvor mye diafragma beveger seg:

As in the case of respiratory frequency, there was no change in respiratory curve amplitude in the control group when a load was applied to the lower limbs (1823 , 1928 ). By contrast, the pathological group showed lowered excursions when load was applied (870 , 540 ). The inter-situational difference was significantly different amongst the groups with . In comparison with the pathological group, the control group had 3 times bigger excursions in situation , and 6.5 times bigger excursions in the situation .

In addition, the measurements showed great motion of the posterior diaphragm part than of the anterior part. In, the antero-posterior ratio was within the control group and within the pathological group. In , the control group raised the range of the posterior part to mm, resulting in an antero-posterior ratio of . The pathological group, by contrast, raised the range in the anterior area and reduced the range in posterior area, resulting in an antero-posterior ratio of .

Om hvordan pusten reagererer annerledes ved ryggsmerter:

We concluded that there was slower and deeper respiratory motion (parameters ) for both observed situations. In addition, after the postural demands rose in situation , the breathing speed increased significantly () in the pathological group. In the same manner the breath depth () lessened significantly () in the pathological group. There were bigger postural moves in the control group, and they remained bigger in both situations, rising equally for each group.

Ved ryggsmerter er diafragma høyere opp i kroppen og lungene blir mindre:

The inclination of the diaphragm was greater (i.e. it was more verticalized) in the control group. The pathological group had the diaphragm placed significantly higher in the trunk, as indicated by the parameter.

Om forholdet mellom diafragma og smerte, hd er høyden på diafragma, jo høyere jo mer smerte:

Diaphragm height were the only diaphragm parameter which was statistically significantly correlated (p = 0.0035) with the subjects’ low back pain indicated during the month before imaging. Pearson correlation coefficient was 0.67.

Om hvor mye diafragma beveger seg:
In the results section, we concluded that there is a statistically significant difference in the range of motion (ROM) of the diaphragm. A two and three times greater ROM was noted in the control group, than in the pathological group in situations and . In addition, the average diaphragm excursions (central part) in situation were mm in the control group and mm in the pathological group. In situation , was mm in the control group and mm in the pathological group.

We observed that the diaphragm was significantly higher for the pathological group. This may be a mechanism by which the pathological group was able to keep the diaphragm excursions more evenly spread after the postural demands increased.

Diafragma beveger seg normalt mer på baksiden:
We also observed that the diaphragm was more contracted in the posterior part for the control group. Diaphragm inclination measurements showed significant lowering of the posterior part of the diaphragm relative to the anterior part of the diaphragm for the control group. The pathological group kept the diaphragm in a more horizontal position.

Suwatanapongched [43]concluded that there was flattening of the diaphragm in the older population in his study. Our results did not show any significant age-related correlation of diaphragm flatness. Instead, the only significant correlation that we observed was between diaphragm height and the LBP intensity of the pathological group during the month before the measurements were made.

Jo høyere opp diafragma er, jo vanskeligerere blir den å bevege:
We assume that this diaphragm bulging is due to worse ability to contract the diaphragm properly. To the best of our knowledge, there are no results in the literature for measurements of diaphragm flatness in subjects suffering from LBP. Worse ability to contract the diaphragm in the pathological group is also supported by the significantly higher position in the trunk.

No correlation was concluded between measured parameters and pain intensity except for bulging (i.e. long term pain) of the diaphragm, as was discussed above. The results indicate that, as the pain is long term, the patients do not change their respiratory patterns according to fluctuations in the chronic LBP.

The significant differences in the harmonicity of the diaphragm motion observed in this study indicate changes in the central nervous system related to diaphragm function in subjects with pathological spinal findings suffering from various intensities of chronic low back pain. Low back pain is a wide-spread and widely studied phenomenon. Alternating respiratory patterns and anatomical changes in the diaphragm have been assessed in LBP subjects. Studies concluding increased susceptibility to pain and injury [1], [13], [49] identified differences in muscle recruitment in people suffering from LBP. Janssens [50] used fatigue of inspiratory muscles, and observed altered postural stabilizing strategy in healthy subjects. Jenssens also observed non-worsening stabilization with an already altered stabilizing strategy in subjects suffering from LBP. Grimstone [51] measured respiration-related body imbalance in subjects suffering from LBP, observing worse stability in subjects with LBP. Kolar [44] investigated differences in diaphragm contractions between healthy subjects and LBP subjects. He observed lesser contractions in the posterior part of the diaphragm while the postural demands on the lower limbs increased, and he suspected that intra-abdominal pressure lowering might be the underlying mechanism of LBP. Roussel [34] assessed the altered breathing patterns of LBP subjects during lumbopelvic motor control tests, concluding that some subjects used an altered breathing pattern to provide stronger support for spinal stability.
In our measurements, we did not observe the same diaphragm excursions in the posterior part of the diaphragm for healthy subjects and for subjects suffering from LBP as were observed by[44]. The excursions were reduced in the pathological group. In contrast with Kolar’s findings[44], we concluded that there was also lowering of the diaphragm inspiratory position in the pathological group in situation . Our measurements support the hypothesis of less diaphragm contraction in the pathological group, with a significant correlation between diaphragm bulging and the intensity of the patient’s low back pain.

Om hvordan magemuskler er nødvendig for diafragma stabilitet:
In the pathological group, the abdominal muscles lack the ability to hold the ribs in lower position. For this reason, the insertion parts of the diaphragm are not fixed and the diaphragm muscle changes its activation. The diaphragm is disharmonic in its motion, which causes problems with providing respiration and at the same time retaining abdominal pressure. The muscle principle for spine stabilization is therefore violated, and is replaced by a substitute model, which tends more easily toward the emergence of low back pain, spine degeneration or disc hernia.

Reversed causation is always a possibility, i.e. it is possible that the diaphragm behavior is changed in order to stabilize the spine after the deep intrinsic spinal muscles fail. During these changes, breathing patterns may occur, e.g. breath holding and decreased diaphragm excursions.

Our study shows a way to compare the diaphragm motion within the group of controls without spinal findings and those who have a structural spinal finding, e.g. a hernia, etc., not caused by an injury. In this way, we confirm our experience of the influence of the diaphragm on spinal stability and respiration. The control group show a bigger range of diaphragm motion with lower breathing frequency. The diaphragm also performs better harmonicity (coordination) within its movement. The postural and breathing components are better balanced. This fact is very important for maintaining the intraabdominal pressure, which helps to support the spine from the front. For this reason, it plays a key role in treating back pain, hernias, etc. In the group of controls we also found a lower position of the diaphragm while it was in inspiration position in tidal breathing and also while being loaded. These facts also support the ability of the diaphragm to play a key role in maintaining the good stability of the trunk. It is also important that we are able to separate the phases of diaphragm movement. This supports both the postural function and the breathing function of this muscle due to MR imaging.