ABSTRACT

Aim:

Non-specific chronic low back pain (LBP) is defined as pain lasting more than 3 months, which is the first among musculoskeletal system diseases. This study aimed to examine and compare the effects of exercises applied with a stretching platform in addition to conservative treatment (CT) and CT only on pain, proprioception, balance, and mobility in patients with chronic LBP.

Material and Methods:

Fifty five people with chronic LBP were included in the study and randomly divided into 2 groups. Group 1 was included in the CT, and group 2 was included in the exercise program applied with a stretching platform in addition to the CT. Pain intensity with visual analog scale (VAS), proprioception sense with the active re-creation of passive positioning method without extremity support, mobility with modified schober test (MST), hand finger-ground distance measurement (HFGDM) and trunk lateral bending measurement (TLBM), balance level with functional reach test (FRT), functionality with oswestry disability index (ODI), and quality of life (QoL) was assessed with the EuroQol Group 5D-3L.

Results:

Statistically significant differences were observed between the results of pain, proprioception, MST, HFGDM and TLBM, FRT, ODI, and EuroQol Group 5D-3L in intragroup evaluations (p<0.05). In intergroup analysis, the VAS score during activity and 15° right ankle plantar flexion in proprioception evaluation were superior in group 2 compared with group 1 (p<0.05).

Conclusion:

It was observed that CT and exercises applied with a stretching platform in the treatment of LBP had positive effects on pain, proprioception, mobility, balance, functionality, and QoL.

Keywords: Low back pain, exercise, balance, proprioception, mobility

INTRODUCTION

Non-specific chronic low back pain (LBP) is defined as pain lasting more than 3 months, which is the first among musculoskeletal system diseases, is located between the lower ribs and the gluteal line, can spread to the lower extremities (1). LBP, with a prevalence of 4-33%, is more common in females over 40 years of age (2, 3). LBP that does not go away with rest, pain in the legs, numbness, and weakness, increased temperature in the pain areas, loss of sensation and tenderness, decreased proprioception sense in the lower extremity joints, lumbosacral joint and facet joints are common symptoms in chronic LBP (4).

Medical, conservative treatment (CT), and surgical approaches are applied for treating LBP. CT approaches include thermotherapy, electrotherapy, exercise training, back schooling, and patient education (5). Thermotherapy is a treatment approach that generally includes hot applications in the chronic period to reduce pain and spasm (6). Electrotherapy is an application in which electrical currents are used to relieve pain and improve muscle function (7). Exercise training significantly reduces the level of pain and the possibility of recurrence of pain, and increasing flexibility by preventing pain-induced kinesiophobia (8). Patient education informs people about correct posture and ergonomics and offers suggestions that will enable people to cope with pain (9).

The reasons for preferring exercises with a stretching platform in our study are to increase the mobility of the lumbar region, reduce the fear of pain-induced movement, and improve the sense of proprioception and dynamic balance in the joints with the stretching effect that will occur in all joints from the lumbar region to the ankle.

Our primarily aim was to examine and compare the effects of exercises applied with a stretching platform in addition to CT in patients with chronic LBP and only CT on pain and secondarily on proprioception, balance, mobility, functionality and quality of life (QoL).

MATERIAL AND METHODS

Participants

Our study, which was designed as a randomized controlled prospective clinical trial (NCT05726955), was conducted in accordance with the Declaration of Helsinki. Ethics committee approval for this study was obtained from the İstanbul Okan University Ethics Committee with decision number (protocol no: 20.10.2021-14, date: 20.10.2021). The study included 55 participants aged 25-65 years, who had LBP for more than 12 weeks and whose pain intensity was greater than 3 on the 10 cm visual analog scale (VAS). Those who have structural deformity, circulatory disorder, and a disease that will prevent mobility in the columna vertebralis, those who have undergone surgery for the columna vertebralis and lower extremity in the last year, and those diagnosed with vertigo and osteoporosis were not included in the study. All volunteers participating in the study were given an informed consent form, and their signed consent was obtained.

Evaluations of pain, proprioception, mobility, balance, functionality and QoL were performed by a physiotherapist, while treatment programs were performed by another physiotherapist in this study. Physiotherapists were blind to each other. The face-to-face the interview method was used for data collection. A consultation was provided by the researchers when the patients had questions. It took about 30 min to complete all assessments.

Sample Size

The sample size of our study was made using PS Power analysis program. In the analysis, the number of samples was determined as 25 individuals in each group using the values of α=0.05, power: 0.80, minimal clinically important difference: 20 mm (VAS), standard deviation: 24.51. Considering the probability of 10% decrease in the participants, it was determined that 55 people should participate in the study (10).

Randomization

The participants were randomized via the “Research Randomiser” website (11). The numbers obtained because of randomization by entering the number of participants (n=55) and the number of groups (group 1 and group 2) were put into envelopes. Participants were assigned to groups according to the numbers on the envelopes they drew. Randomization was done in secret, blinding the groups and preventing the participants from meeting the other group.

Groups

Group 1 (n=27) were included in a CT program and group 2 (n=28) were included in an exercise training program applied with CT and a stretching platform 3 days a week for 6 weeks. Severity of pain, proprioception, mobility, balance, functionality, and QoL assessments of all participants were performed before and after the treatment. The participation status, assessments, and treatment methods applied to the participants were as shown in the flow diagram below (Figure 1).

Figure 1

Assessments

Demographic data including age, height, body weight, body mass index (BMI), previous diseases, and smoking habits of the participants who participated in the study were evaluated. To evaluate the severity of pain at night, at rest, and during activity, VAS was used, which digitizes the parameter values that cannot be measured numerically by numbering them from 0 to 10, where “0” is no pain and “10” is very severe pain (12).

In the method of actively recreating passive positioning without supporting the extremity, in which a goniometer is used to evaluate the proprioception sense, the extremity was passively moved to the target angle while the participant’s eyes were closed, and the participant returned to the starting point after focusing on the position for 10 seconds. The participant tried to find the target angle by actively moving the same extremity, and the difference was recorded as the deviation angle (13).

Modified schober test (MST), hand finger-ground distance measurement (HFGDM), and trunk lateral bending measurement (TLBM) were used to evaluate the level of mobility. In the MST, 5 cm below and 10 cm above the line connecting the spinal iliaca posterior superior were marked with the help of a tape measure while the participant was in an upright position. While the participant was performing maximum trunk flexion, the distance between the two points was measured and 15 cm was subtracted from this measurement. If the difference is less than 5 cm, it is MST (+). This result indicates that lumbar region mobility decreases (14, 15). In HFGDM, the participant is asked to bend forward and perform maximum flexion while in an upright position. In TLBM, the participant was asked to lean to the side with his arms on both sides of the body, with his shoulder and gluteal region resting against the wall. In both measurements, the distance between the third finger and the ground was measured with the help of a tape measure. Lumbar mobility increases as the distance between the finger and the floor decreases in TLBM and HFGDM (16).

Functional reach test (FRT) was used for balance assessment. The participant was positioned to stand sideways against the wall. The shoulder on the wall was brought to 90° flexion and the elbow to full extension, and the participant was asked to make a fist with the same arm. The alignment of the 3^rdmetacarpal head was marked on the wall. The participant reached forward with the knees fully extended and the level of the third metacarpal head was marked again. The difference between the two marks was measured using a tape measure. The average value was obtained after 3 trials. The same application was repeated with eyes closed. The greater the difference between the marked points in FRT, the better the balance (17, 18).

The oswestry disability index (ODI) was used for functionality assessment. ODI is a scale that evaluates the degree of the loss of function in LBP between “0” and “100” points. As the score in ODI increases, the level of disability increases (19).

The EuroQol Group 5-dimension 3-level (EQ-5D-3L) QoL scale was used for QoL assessment. The 1^st item of the parameters evaluated in the 1^stpart of the scale includes the expressions “no problem”, the 2^nd item “moderately severe problem” and the 3^rd item “very severe problem”. In scoring, '11111' represents complete well-being, and '33333' represents coma or death. Section 2 contains VAS, with 100 representing “excellent health” and 0 representing “very poor health” (20).

Treatment Program

All participants included in the study received CT 3 days a week for 6 weeks. CT included a 20-minute hot pack and conventional transcutaneous electrical nerve stimulation and William’s flexion exercises applied to the lumbar region. The exercises performed on the stretching platform designed to stretch the lumbar, gluteal, and posterior parts of the lower extremity were applied only to the participants in group 2 for 3 days a week for 6 weeks after Williams flexion exercises (Table 1).

Table 1

Statistical Analysis

The SPSS statistical package program was used to evaluate the data. For homogeneity of variances, which are prerequisites of parametric tests, “Levene test”, the normality assumption "Shapiro-Wilk test", the differences between two independent groups “Student’s t-test” and “Mann-Whitney U test”, and the differences between the two dependent groups “Paired t-test” and the “Wilcoxon sign test” were used. Relationships between categorical variables were analyzed with Fisher’s exact test and chi-square test. In the analysis of frequencies less than 20%, evaluation was made with the “Monte Carlo simulation method”. A p<0.05 level was considered statistically significant.

RESULTS

The demographic and clinical characteristics of the participants are shown in Table 2. It was determined that the two groups were similar in terms of demographic and clinical characteristics (p>0.05), (Table 2).

Table 2

In intragroup analysis, a statistically significant decrease was found in VAS scores at rest, night, and activity (Table 3), measurement of right and left TLBM, and a statistically significant increase was found in proprioception (Table 4), measurement of MST, HFGDM, FRT, and eyes-closed FRT (Table 5), ODI (Table 6), EQ-5D-3L, and EQ-5D-3L-GAS (p<0.05), (Table 6).

Table 3

Table 4

Table 5

Table 6

In intergroup analysis, the improvement in VAS activity and in 15° right ankle plantar flexion proprioception was found to be superior in group 2 compared to the group 1 (p<0.05),
(Tables 3, 4). The improvement of 60° right hip flexion and 15° left ankle plantar flexion proprioception and TLBM were found to be superior in group 1 compared with group 2 (p<0.05), (Tables 4, 5).

DISCUSSION

In this study, we examined and compared the effects of exercises applied with a stretching platform in addition to CT and only CT in patients with LBP on pain, proprioception, balance, mobility, functionality and QoL.

In previous studies, when the demographic characteristics of people with chronic LBP are examined, it is seen that the probability of chronic LBP is higher in people aged 40 and over, females, and people with a BMI of 25 kg/m² and above (21, 22). In our study, the mean age of chronic LBP was 45.26±10.68 years in group 1 and 44.18±9.53 years in group 2. The mean BMI value was found to be 25.58±4.24 kg/m² in group 1 and 28.25±5.19 kg/m² in group 2. In addition, it was found that chronic LBP was more common in females compared to males with a rate of 70% in group 1 and 64% in group 2.

VAS is generally used for pain assessment in chronic LBP because of its easy application. In addition, in pain assessment, evaluating the pain according to its course during the day and its severity at rest and activity enables faster solutions to be developed by determining the causes of chronic LBP. In the studies conducted and in our study, it was determined that pain was felt most during activity in chronic LBP, while night pain was felt the least (23-25). We think that the reason why night pains are less is the decrease in the load on the bones, joints, ligaments and intervertebral disk in the column vertebralis compared to standing and sitting positions while lying down. When studies conducted to reduce pain and improve function in chronic LBP were examined, it was found that only stretching exercises were not effective on pain compared to other exercise training (26-29). In our study, the exercise program applied with a stretching platform was not found to be superior to the CT program in reducing the level of pain, and it was found that CT and exercises applied with a stretching platform were effective in reducing the pain score in chronic LBP. We think that the exercises performed with the stretching platform cause extra stretching in the calf group muscles, providing relaxation of the lower kinetic chain and relaxation of the lumbar region muscles, that the person feels less pain during the activity, and that our study may contribute to the literature thanks to this effect provided by the stretching platform.

There is a positive correlation between decreased proprioception sense and the loss of balance and function in people with chronic LBP (30). For this reason, the ability of exercise approaches to accelerate the proprioceptive response by improving the sensitivity of the spinocerebellar and dorsal lateral-medial lemniscal pathways is used (31). There is no study in the literature on the effect of stretching exercises on proprioception in people with chronic LBP. In our study, it was found that CT and exercises applied with a stretching platform improved the sense of proprioception in people with chronic LBP. We think that in addition to the stretching effect of the exercises and flexion exercises performed with the stretching platform on the lumbar region and lower extremity muscles, the forward bending exercises with the eyes closed and the knees semi-flexed on the stretching platform increase the sense of joint position and the sense of joint movement in the joints of the lower extremity and lumbar region. It improves the sense of proprioception.

It is stated in previous studies that pain causes avoidance of movement in people with chronic LBP and therefore negatively affects mobility; therefore, adding different exercise approaches to exercise training programs for people with chronic LBP reduces pain levels as well as contributes to mobility and balance (10, 26, 32-35). In our study, MST, HFGDM, and TLBM methods were used to evaluate the mobility levels of people with chronic LBP. According to the data we have obtained, results that will contribute to the improvement of the level of mobility have emerged in both groups in MST, HFGDM, and TLBM methods. We think that the reason for this situation is that the exercises applied with the stretching platform and flexion exercises create a stretching effect on the lumbar and lower extremity muscles, and the hot pack application in the lumbar region causes an increase in the mobility of the lumbar region by relaxing the non-contractile tissues.

In people with chronic LBP, pain negatively affects balance and mobility. In general, exercise approaches positively affect balance by increasing the sense of joint position (31). When the studies in the literature are examined, it is seen that stretching exercises contribute the most to the development of balance among exercise approaches. However, we understand that only periods of 30 s or less improve balance, and therefore, the most important factor in the effect of stretching exercises on balance is the duration of stretching (32, 35-37). According to the data we obtained in our study, FRT with eyes open and FRT with eyes closed increased in both groups, showing that the balance level of the participants improved. This result shows that forward bending exercises with one foot and eyes closed and the modified straightening exercise, which is one of the flexion exercises, applied with a stretching platform are directly effective in increasing the FRT scores. In addition, it is thought that the stretching effect of the exercises applied with the stretching platform and the stretching exercise applied to the hamstring muscle, which is one of the flexion exercises, on the lumbar region and lower extremity muscles triggers the development of balance by increasing the sense of joint position and joint movement.

In a study examining the functionality level of 225 people with LBP, it was reported that ODI is a reliable scale that evaluates chronic LBP in a multidimensional way (38). In our study, an increase in functionality was achieved in both groups according to ODI scores. This result suggests that exercises applied with a stretching platform are as effective as CT in improving the level of functionality in chronic LBP. We think that the stretching effect of the exercises applied with the stretching platform on the muscles of the lower extremities and lumbar region, as well as the stretching exercise for the hamstring muscle in the flexion exercises and the modified straightening exercise, and the diversification of these exercises by bending forward and sideways, standing on one leg, eyes closed, increased the functionality of the participants. Our study can contribute to the literature in this respect.

In the literature, it is seen that the use of the two scales together in chronic LBP yields more objective findings since the EQ-5D-3L scale is valid and reliable for QoL assessment and has a strong correlation with ODI (39-42). This result suggests that exercises applied on the stretching platform are as effective as CT in improving the QoL of people with chronic LBP. However, in the literature, there is no QoL assessment with the EQ-5D-3L scale for treating chronic LBP. In our study, an increase was observed in the QoL VAS score in both groups. This result suggests that exercises applied on the stretching platform are as effective as CT in improving the QoL of people with chronic LBP.

Study Limitations

The limiting factors of the study were the inability to examine the long-term effects of exercises due to the Coronavirus disease-2019 pandemic and the inability to use objective measurement methods because of existing clinical opportunities.

CONCLUSION

It was concluded that CT and exercises applied with a stretching platform in addition to CT in patients with chronic LBP reduce pain and increase proprioception, mobility, balance, functionality, and QoL. Since there is no consensus on the content of the exercises performed on the stretching platform, the duration of application, and the nature of passive or dynamic stretching, there is a need for studies that objectively evaluate the effectiveness of different types of exercise training using this exercise support and examine the long-term results.

Ethics

Ethics Committee Approval: Ethics committee approval for this study was obtained from the İstanbul Okan University Ethics Committee with decision number (protocol no: 20.10.2021-14, date: 20.10.2021).

Informed Consent: All volunteers participating in the study were given an informed consent form, and their signed consent was obtained.

Peer-review: Externally peer-reviewed.

Authorship Contributions

Surgical and Medical Practices: G.A., E.A., Concept: C.A.K., G.A., E.A., Design: C.A.K., G.A., Data Collection or Processing: C.A.K., G.A., Analysis or Interpretation: G.A., E.A., Literature Search: C.A.K., G.A., E.A., Writing: C.A.K., G.A., E.A.

Conflict of Interest: The authors have no conflicts of interest to declare.

Financial Disclosure: The authors declared that this study received no financial support.

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EFFECTS OF EXERCISE USING A STRETCHING PLATFORM ON PAIN, PROPRIOCEPTION, BALANCE, AND MOBILITY IN PATIENTS WITH NON-SPECIFIC CHRONIC LOW BACK PAIN