Comparison of head posture and neck proprioceptive sense of individuals with chronic neck pain and healthy controls: A cross-sectional study

Abstract

BACKGROUND:

Chronic pain can affect body perception at the central level by causing the somatosensory cortex to rearrange. Additionally, cervical afferent abnormalities in individuals with neck pain can impair proprioceptive sensitivity, potentially leading to alterations in body alignment and biomechanics. Nevertheless, there are insufficient studies exploring these notions.

OBJECTIVE:

The main objective of this study was to compare the head posture and neck proprioceptive sense of individuals with chronic neck pain and healthy controls.

METHODS:

Utilizing a cross-sectional study, a total of 76 volunteers comprising 38 individuals with neck pain and 38 matched healthy controls participated in the study. Head posture and cervical joint position sense were measured using a Cervical Range of Motion Deluxe (CROM) device. Firstly, the deviation angles of the head in three planes were evaluated, then the Head Repositioning Accuracy (HRA) test was performed to determine the joint position error. Visual Analogue Scale (VAS) was used to determine the severity of pain in individuals with neck pain.

RESULTS:

The deviation angles of the head in all three planes were significantly lower in the healthy control group ( $p<$ 0.05). Joint position error values were significantly higher in all directions (flexion-extension, right-left lateral flexion, and rotation) in the neck pain group ( $p<$ 0.001).

CONCLUSION:

The findings show that the proprioceptive sensation of the cervical region in individuals with neck pain was adversely affected, with changes were observed in the head posture.

NOTE:

The abstract of this study was presented as a verbal declaration at the International Congress of Health Sciences-ICHES-IDU 2020 that was held in İzmir on 20–21 June 2020.

Keywords

Neck pain position sense posture proprioception proprioceptive disorders

1. Introduction

The term proprioception is defined as the ability of an individual to perceive the position and movements of his body [1]. It also refers to the conscious or unconscious awareness of force, weight, and effort, as well as sense and kinesthesia of joint position [2]. Muscle spindles, which are located parallel to the extrafusal muscle fibers in all skeletal muscles [3], are widely regarded as the primary source of proprioceptive information [4]. Amonoo-Kuofi observed a high-density muscle spindle in the deep cervical muscles, especially in the transition areas of the cervicothoracic and thoraco-lumbar joints, and in the middle layers of the muscles of the cervical region. He also noted a prominent elevation in muscle spindle density within the deep layer of the upper cervical spine compared to the lower cervical spine [5]. Lately, variations in the density, shape, and arrangement of muscle spindles have been detected in the longus colli and multifidus muscles of the cervical spine [6]. Furthermore, elevated muscle spindle density was observed in the small muscles of the suboccipital triangle [7, 8]. The findings indicate that these muscles may contribute to the precise control of head and neck position sense. Cervical proprioceptive sensation provides sensory feedback to the brain about the position and movement of the head and neck [9]. This feedback contributes to postural control and balance, including the maintenance of proper head posture [10]. Dysfunction in cervical proprioception can affect neck muscle coordination and lead to changes in head posture.

Proprioception plays multiple roles in sensory-motor control. The central nervous system (CNS) requires an updated framework illustrating the biomechanical and spatial characteristics of body parts necessary for generating precise motor commands informed by proprioceptive input [11]. Proprioception is also important after movement in order to compare the action performed with the objective of the movement [2, 12]. Reduced proprioception impacts posture by altering movement control, as well as the precision and timing of motor commands [13, 14]. Numerous studies have documented compromised proprioception in both acute and chronic musculoskeletal pain conditions affecting the cervical and lumbar spine, as well as the upper and lower extremities [2, 15, 16]. Activation of reflex activity and chemo sensitive type III and IV afferents during painful episodes can lead to alterations in the sensitivity of the gamma-muscle spindle system, potentially resulting in a decline in proprioceptive function [2]. Additionally, experimental pain models have shown impairment of proprioception [17]. In addition, pain can affect body perception in the brain thus causing neuroplasticity in the somatosensory cortex [18, 19]. Studies have shown that there is deterioration of proprioception in patients with pain in the cervical region. Sjolander et al. reported that people with neck pain and whiplash-related disorders have problems with joint position sense [15]. Similarly, Treleaven et al. also reported that people with whiplash-related disorder experience difficulty in sensation of their joint position [16]. Consequently, altered sensory input and impaired proprioceptive sensation, often in combination with pain, can result in significant changes in head posture.

Investigating head posture and neck proprioceptive sensation in patients with chronic neck pain may have various benefits in clinical, diagnostic, and therapeutic contexts. By assessing differences in head posture and neck proprioception, clinicians can better understand the extent of proprioceptive dysfunction and postural deviations in individuals with chronic neck pain, thus enabling the development of individualized treatment plans. These assessments can also be utilized to monitor the progression of the condition and the effectiveness of interventions over time. Interventions can be customized to address specific impairments in proprioception and posture, thereby improving therapeutic outcomes by enhancing sensory feedback mechanisms. Additionally, investigating proprioceptive and postural differences may provide insights into the pathophysiologic mechanisms underlying chronic neck pain, which can inform the development of new therapeutic targets and intervention strategies. Given these potential benefits, the objective of this study was to assess and compare head posture and proprioceptive sense of the cervical region between patients experiencing chronic neck pain and healthy individuals. The hypothesis suggested that neck pain might lead to both impaired head posture and compromised proprioceptive sensation.

2. Methods

2.1 Study design

A cross-sectional study was conducted from February to April 2020. Two groups were composed: one including individuals with neck pain (neck pain group) another including healthy individuals with similar characteristics (healthy control group). Data on the deviation of the head from the three planes and the proprioceptive sense of the cervical region were collected jointly by three physiotherapists.

2.2 Participants

Written informed consent was obtained from the participating individuals. The procedures were performed according to the Declaration of Helsinki and ethical approval was obtained from the KTO Karatay University Faculty of Medicine Pharmaceuticals and Non-Medical Devices Research Ethics Committee (Permission number $=$ 2020/015, Date: February 24, 2020). The neck pain group consisted of individuals who were examined and referred for the study by physicians. These physicians were interviewed and informed about the study before its commencement. The healthy control group consisted of healthy individuals with similar characteristics in terms of age, body mass index, and gender, primarily working at universities and without neck pain. The neck pain group included patients aged of 18 to 65 years who had experienced neck pain for more than three months and had no neurological deficits (severe strength losses, deep tendon reflex changes, balance and coordination problems and autonomic symptoms). Exclusion criteria included a history of spinal tumor or surgery, diagnosis of cervical dystonia, whiplash-related disorders, vertigo, fibromyalgia, rheumatoid arthritis or other inflammatory disease and/or current infection. The healthy control group included individuals aged 18 to 65 years who had not suffered from neck pain in the past year and had no neurological or rheumatological conditions.

2.3 Sample size

Sample size was calculated using GPower (version 3.0.10; Franz Faul, Universität Kiel, Germany) and determined based on the mean and standard deviation of joint position error measurements in the flexion position [20]. To attain a power of 0.90 with an effect size of 1.76 at a significance level of 0.05, each group required a minimum of 8 participants. However, to increase the power of the study, reduce the risk of Type II error, and obtain more reliable results, all participants who met the criteria were evaluated, resulting in 38 individuals being included in both the neck pain group and the control group.

2.4 Outcome measures

2.4.1 Primary outcomes: Head posture and joint position sense

Head posture and cervical joint position sense were measured using the Cervical Range of Motion Deluxe (CROM) (Deluxe Performance Attainment Associates, Lindstrom, MN, USA) device. CROM device is a well-known device used to safely evaluate neck movements [21, 22]. The CROM device consists of a plastic frame mounted on the individual’s nasal bridge and ears and fixed on the head with the help of a velcro. The three dial-operated angle meters, which was attached to the frame and arranged orthogonally to each other, was employed to measure the degree of individual’s cervical movements. Neck flexion, extension and lateral flexion movements were measured with gravity goniometers. Cervical rotation movements were measured with a compass goniometer that works with a magnetic apparatus placed on the shoulder in the North direction [22]. The seat on which the patients sit was positioned accordingly in order to reset the rotation dial of the magnetic field. Patients were asked to sit in an upright position in the chair so as to create some distance behind the chair with their thoracic spine, and also flatten their feet on the floor [21].

Figure 1.

Using CROM device to evaluate joint position sense.

2.4.2 Head posture: The deviation angles of the head in three planes

For a start, the eyes of the participants were closed with an eye patch. The participants were asked to keep their heads in the usual position, and the deviation angles of the head from the 0 position in all three planes were recorded (Fig. 1).

2.4.3 Joint position error/head repositioning accuracy test

The Head Repositioning Accuracy (HRA) values, assessing the capacity to actively position the head in a designated reference position within a specific plane of motion to determine joint position error, were measured [23]. It has been demonstrated in numerous studies that the use of CROM device is a reliable method to evaluate HRA [24, 25, 26, 27]. Before evaluating the joint position error, the maximum active range of motion (ROM) values in all three planes of the participants were measured. Further, half of these values (midpoint) was determined and referenced as the target position [28]. The heads of the participants were slowly adjusted to the target position by the investigators. The heads were kept in this position for 3 seconds, and at this point, the participants were asked to perceive the position. Thereafter, the participants were asked to move their heads in the opposite direction to return to the target position again and confirm it. Before each trial, the heads of the participants were placed to the target position again, and the same procedure was repeated 3 times. The average of the absolute difference between the target positions was then calculated. The order of direction of movement was determined by simple draw method. Thus, the trials for flexion, extension, right-left rotation, and lateral flexion were applied separately. After evaluation of each movement direction, a break was provided for one minute. To prevent errors and ensure objectivity, each assessment was performed by two physiotherapists, with a third physiotherapist conducting the final check and recording the data.

2.4.4 Pain severity

Patients with neck pain assessed the severity of pain during activity using the Visual Analogue Scale (VAS), marking their pain levels on a scale ranging from 0 to 10 centimeters. A score of “0” denotes the absence of pain, whereas a score of “10” represents the highest imaginable level of pain. The indicated points were measured and recorded in centimeters [29].

2.5 Data analysis

Statistical Package Program, SPSS Version 25 (IBM Corp., Armonk, NY, USA), was used to analyze the data. Variables were checked for normality and homogeneity (Shapiro Wilk and Levene Test). The student’s independent t-test was employed to assess variations between two normally distributed groups, whereas the Mann-Whitney U test was utilized to evaluate differences between two groups that were not normally distributed. Age, Body Mass Index (BMI), and pain severity were expressed as mean $\pm$ standard error while the other variables were expressed as median (1st Quarter-3rd Quarter). The relationship between two continuous variables was evaluated using Spearman’s correlation coefficient since the necessary conditions for parametric testing were not met. The correlation coefficient (r) was interpreted as follows: very weak (0.00–0.25), weak (0.26–0.49), moderate (0.50–0.69), strong (0.70–0.89), and very strong (0.90–1.0) [30]. A $p<$ 0.05 is considered statistically significant.

Table 1
Demographic data of the participants

	Neck pain group ( $n=$ 38)		Healthy control group ( $n=$ 38)
	Mean	SE	Mean	SE	$p$
Age (years)	38.8	1.5	40.1	1.1	0.484^a
BMI (kg/m²)	25.9	0.7	24.3	0.6	0.081^a
Pain severity (cm)	6.5	0.3	–	–

^{*p <} 0.05 Statistical significance, SE: Standard error, $n$ : Number of participants, BMI: Body mass index, ^a: Independent $t$ Test.

3. Results

3.1 Participants

Thirty-eight patients (30 female, 78.9%) with a mean age of 39 years (range 20 to 54) in the neck pain group and 38 (30 female, 78.9%) healthy volunteers with a mean age of 40 years (range 27 to 57) in the control group participated in the study in accordance with the inclusion criteria. In the neck pain group, 11 patients (29%) had disc problems, 27 patients (71%) had mechanical neck pain. The mean duration of symptoms for individuals in the neck pain group was 75.92 $\pm$ 59.53 months. Age, BMI and pain severity of the participants, and comparison of each variable between groups are shown in Table 1.

3.2 Primary outcomes

3.2.1 Head Posture: The deviation angles of the head in three planes

Table 2
Comparison of the deviation angles of the head from all three planes

	Neck pain group ( $n=$ 38)	Healthy control group ( $n=$ 38)
	Mean $\pm$ SD median (Q1–Q3)	Mean $\pm$ SD median (Q1–Q3)	$Z$	$p$ /effect size
Deviation angles of the head from the	3.89 $\pm$ 3.14	1.32 $\pm$ 2.24	$-$ 4.5	$<$ 0.001^*,b
frontal plane (^∘)	4 (2–5.3)	0 (0–2)		0.731
Deviation angles of the head from the	10.45 $\pm$ 5.23	6.24 $\pm$ 4.30	$-$ 3.6	$<$ 0.001^*,b
sagittal plane (^∘)	10 (7.5–14)	6 (2–10)		0.733
Deviation angles of the head from the	5.00 $\pm$ 3.95	3.34 $\pm$ 3.48	$-$ 2.1	0.036^*,b
horizontal plane (^∘)	4 (2–8)	2 (0–6)		0.736

^{*p <} 0.05 Statistical significance, $n$ : Number of participants, SD: Standard deviation, Q1: Quartile 1, Q3: Quartile 3, ^b: Mann whitney U test.

The angles of deviation of the head from all three planes was found significantly (frontal plane: $Z$ (74) $=-$ 4.50, $p<$ 0.001, effect size (ES) $=$ 0.731; sagittal plane: $Z$ (74) $=-$ 3.60, $p<$ 0.001, ES $=$ 0.733; horizontal plane: $Z$ (74) $=$ $-$ 2.10, $p=$ 0.036, ES $=$ 0.736) lower in the healthy control group (Table 2). There was no significant difference in the angles of deviation of the head across all three planes between patients with disc problems and those with mechanical neck pain (frontal plane: $Z$ (36) $=-$ 0.538, $p=$ 0.612, ES $=$ 0.087; sagittal plane: $Z$ (36) $=-$ 0.953, $p=$ 0.356, ES $=$ 0.154; horizontal plane: $Z$ (36) $=-$ 0.049, $p=$ 0.975, ES $=$ 0.008). In both patients with disc problems (frontal plane: $Z$ (47) $=-$ 2.818, $p=$ 0.005, ES $=$ 0.401; sagittal plane: $Z$ (47) $=-$ 2.924, $p=$ 0.003, ES $=$ 0.417; horizontal plane: $Z$ (47) $=-$ 1.685, $p=$ 0.092, ES $=$ 0.241) and patients with mechanical neck pain (frontal plane: $Z$ (63) $=-$ 4.312, $p<$ 0.001, ES $=$ 0.534; sagittal plane: $Z$ (63) $=-$ 2.968, $p=$ 0.003, ES $=$ 0.368; horizontal plane: $Z$ (63) $=-$ 1.762, $p=$ 0.078, ES $=$ 0.218), the deviation angles of the head in planes other than the horizontal plane were significantly higher than in the healthy control group.

Table 3

Comparison of joint position error values with HRA test

Joint position error/HRA test	Neck pain group ( $n=$ 38)	Healthy control group ( $n=$ 38)
	Mean $\pm$ SD median (Q1–Q3)	Mean $\pm$ SD median (Q1–Q3)	$Z$	$p$ /effect size
Flexion (^∘)	4.23 $\pm$ 2.25	1.12 $\pm$ 0.95	$-$ 6.6	$<$ 0.001^*,b
	3.8 (2.3–5.5)	1.3 (0–2)		0.727
Extension (^∘)	3.35 $\pm$ 2.06	0.96 $\pm$ 0.83	$-$ 5.8	$<$ 0.001^*,b
	3.3 (1.7–4.1)	0.66 (0.50–1.3)		0.728
Right lateral flexion (^∘)	3.72 $\pm$ 2.11	0.80 $\pm$ 0.85	$-$ 6.9	$<$ 0.001^*,b
	3.3 (2.6–4.5)	0.66 (0–1.3)		0.726
Left lateral flexion (^∘)	3.63 $\pm$ 2.36	0.64 $\pm$ 0.65	$-$ 6.6	$<$ 0.001^*,b
	3.2 (1.9–4.7)	0.66 (0–0.66)		0.727
Right rotation (^∘)	4.65 $\pm$ 2.79	1.08 $\pm$ 0.92	$-$ 6.6	$<$ 0.001^*,b
	4.3 (2.7–5.7)	1 (0.58–1.3)		0.727
Left rotation (^∘)	4.40 $\pm$ 1.92	0.70 $\pm$ 0.87	$-$ 7.2	$<$ 0.001^*,b
	4 (3–6)	0.66 (0–0.66)		0.726

^{*p <} 0.05 Statistical significance, $n$ : Number of participants, HRA: Head repositioning accuracy, SD: Standard deviation, Q1: Quartile 1, Q3: Quartile 3, ^b: Mann whitney U test.

3.2.2 Joint position error/head repositioning accuracy test

It was observed that joint position error values were significantly higher in all directions (flexion: $Z$ (74) $=-$ 6.60, $p<$ 0.001, ES $=$ 0.727; extension: $Z$ (74) $=-$ 5.80, $p<$ 0.001, ES $=$ 0.728; right lateral flexion: $Z$ (74) $=-$ 6.90, $p<$ 0.001, ES $=$ 0.726; left lateral flexion: $Z$ (74) $=-$ 6.60, $p<$ 0.001, ES $=$ 0.727; right rotation: $Z$ (74) $=-$ 6.60, $p<$ 0.001, ES $=$ 0.727; left rotation: $Z$ (74) $=$ $-$ 7.20, $p<$ 0.001, ES $=$ 0.726) in the neck pain group (Table 3). There was no significant difference in joint position error values in all directions between patients with disc problems and those with mechanical neck pain (flexion: $Z$ (36) $=-$ 1.631, $p=$ 0.108, ES $=$ 0.264; extension: $Z$ (36) $=$ $-$ 0.791, $p=$ 0.446, ES $=$ 0.128; right lateral flexion: $Z$ (36) $=-$ 0.793, $p=$ 0.446, ES $=$ 0.128; left lateral flexion: $Z$ (36) $=-$ 0.824, $p=$ 0.427, ES $=$ 0.133; right rotation: $Z$ (36) $=-$ 0.420, $p=$ 0.680, ES $=$ 0.068; left rotation: $Z$ (36) $=-$ 1.212, $p=$ 0.238, ES $=$ 0.196). It was found that joint position error values were significantly higher in all directions in both patients with disc problems (flexion: $Z$ (47) $=-$ 4.331, $p<$ 0.001, ES $=$ 0.618; extension: $Z$ (47) $=-$ 4.541, $p<$ 0.001, ES $=$ 0.648; right lateral flexion: $Z$ (47) $=-$ 4.615, $p<$ 0.001, ES $=$ 0.660; left lateral flexion: $Z$ (47) $=-$ 4.778, $p<$ 0.001, ES $=$ 0.682; right rotation: $Z$ (47) $=-$ 4.551, $p<$ 0.001, ES $=$ 0.650; left rotation: $Z$ (47) $=-$ 4.998, $p<$ 0.001, ES $=$ 0.714) and those with mechanical neck pain compared to healthy controls (flexion: $Z$ (63) $=-$ 6.094, $p<$ 0.001, ES $=$ 0.756; extension: $Z$ (63) $=-$ 4.939, $p<$ 0.001, ES $=$ 0.612; right lateral flexion: $Z$ (63) $=-$ 6.276, $p<$ 0.001, ES $=$ 0.778; left lateral flexion: $Z$ (63) $=-$ 5.934, $p<$ 0.001, ES $=$ 0.735; right rotation: $Z$ (63) $=-$ 6.019, $p<$ 0.001, ES $=$ 0.746; left rotation: $Z$ (63) $=-$ 6.512, $p<$ 0.001, ES $=$ 0.807).

Active extension ( $Z$ (74) $=-$ 2.683, $p=$ 0.007, ES $=$ 0.307) and right lateral flexion ( $Z$ (74) $=-$ 2.601, $p=$ 0.009, ES $=$ 0.298) ROM grades were higher in the healthy control group and similar in other directions (flexion: $Z$ (74) $=$ $-$ 1.799, $p=$ 0.072, ES $=$ 0.206; left lateral flexion: $Z$ (74) $=-$ 1.560, $p=$ 0.119, ES $=$ 0.178; right rotation: $Z$ (74) $=-$ 1.378, $p=$ 0.168, ES $=$ 0.158; left rotation: $Z$ (74) $=-$ 1.249, $p=$ 0.212, ES $=$ 0.143).

Table 4
The relationship between pain severity, head posture, and neck proprioceptive sense in individuals with neck pain

		Pain severity
		$r$	$p$
Angles of deviation of the head from cardinal planes	Frontal plane	0.163	0.327
	Sagittal plane	0.162	0.330
	Horizontal plane	0.129	0.438
Joint position error	Flexion	0.208	0.209
	Extension	$-$ 0.115	0.491
	Right lateral flexion	0.403	0.012^*
	Left lateral flexion	0.152	0.364
	Right rotation	0.163	0.328
	Left rotation	$-$ 0.169	0.309

^{*p <} 0.05 Statistical significance, $r$ : Correlation coefficient, ^a: Weak correlation (0.26–0.49), Spearman’s correlation coefficient.

In patients with neck pain, a weak positive correlation was found between pain severity and right lateral flexion joint position error ( $r=$ 0.403, $p=$ 0.012; Table 4).

4. Discussion

In this study, participants experiencing chronic neck pain exhibited elevated angles of deviation of the head from the cardinal planes, along with a notable decline in their joint position sense.

The relationship between neck pain and poor posture is complex and bidirectional. Individuals with neck pain often tilt their head forward or sideways to reduce discomfort, which can lead to poor posture. Pain can also cause certain muscles to become overactive and tense while others weaken, resulting in muscle imbalances and altered posture. Conversely, incorrect posture can increase the mechanical load on the cervical spine and muscles, causing muscle fatigue, tension, and pain. Many studies on joint position error in neck pain patients overlook the permanent postural changes resulting from proprioceptive disorders. Neck pain is known to cause sagittal plane changes, such as increased thoracic flexion and forward head posture [31]. However, there is a lack of studies reporting changes in the frontal and horizontal planes. The data obtained from our study indicate that the head positions of individuals with chronic neck pain significantly deviated in all three planes investigated. This deviation was largest in the sagittal plane, consistent with existing literature. The least deviation was found in the frontal plane, where cervical area mobility is the least. Interestingly, no significant difference was observed between individuals with disc problems and those with mechanical neck pain, suggesting similar biomechanical disturbances regardless of the specific pathology. Conversely, individuals with different diagnoses exhibited significantly higher deflection angles in the frontal and sagittal planes compared to healthy controls, while deflections in the horizontal plane were higher but not statistically significant. However, it is important to acknowledge that the numerical differences in the neck pain subgroups were a limiting factor in interpreting the results. Stimulation of chemically sensitive pain receptors in the cervical facet joints and muscles can alter the sensitivity of the muscular spindle, with reflex activation of fusimotor neurons. Consequently, this scenario could result in reduced proprioceptive accuracy, alterations in cortical representation, and modulation of cervical afferent input [32, 33]. Pain can affect the perception of the body at the central level subject to rearrangement of the somatosensory cortex [18, 19]. It is observed that the deterioration in the right proprioceptive information flow causes a wrong body development image in the brain, and permanent deviations in the postural alignment over time. Unfortunately, many patients are not aware of their inaccurate body posture as a result of the change in their perceived body image. Therefore, the structures in the cervical region are exposed to various stress which can negatively affect the recovery of patients. This case suggests that improvement of the correct body image, and paying attention to body alignment, may increase the chance of a successful treatment of the neck pain.

We found a significant impairment in joint position sense in patients with chronic neck pain, which was supported by a separate comparison of the neck pain group with healthy controls, encompassing both those with disc problems and those with mechanical neck pain. Moreover, no significant difference emerged between patients with disc problems and those with mechanical neck pain, indicating similar proprioceptive impairments across these conditions. This finding aligns with previous studies in the literature, affirming the consistency of high impairment in joint position sense among individuals with chronic neck pain [1, 20, 34]. It has been reported that the ability of people with chronic idiopathic neck pain to re-position their head in the neutral position was worse than that of the asymptomatic controls [34]. Alahmari et al. reported that cervical joint position sense was impaired in patients with chronic neck pain when compared to healthy individuals [1]. Reddy et al. reported that proprioception was impaired in patients with cervical spondylosis and that this impairment was positively associated with severity of the pain [20]. The degree of joint position error observed in our study were lower than those obtained by Alahmari et al. [1] and Reddy et al. [20]. This may be arisen from our showing the target position to the participants again after each measurement, as it was applied in some other studies [35]. Placing the head in the target position passively and repeating it several times with active movement may cause a shift in concentration of the individuals from the target position to the sense of motion. Therefore, we asked the participants to perceive this position by taking their heads to the target position after each trial. Herein, we sought to ascertain the difference between the two groups in terms of joint position sense. Contrary to our findings, studies have shown that neck pain does not affect proprioception. According to Arimi et al., there was no correlation found between cervical proprioception and the structure/function of deep flexor muscles, nor with the clinical characteristics of chronic neck pain [35]. Furthermore, using different evaluation methods and equipment can affect the results obtained.

Neck ROM may influence head posture and cervical proprioception. Our results demonstrate that healthy controls exhibited significantly higher ROM in active extension and right lateral flexion compared to individuals with neck pain, indicating greater restriction in these movements among neck pain patients. However, no significant differences were observed in other directions, suggesting that certain aspects of ROM may be less affected. Furthermore, we identified a weak positive correlation between pain intensity and right lateral flexion joint position error in neck pain patients, indicating that higher pain levels correlate with increased proprioceptive inaccuracy during right lateral flexion. These findings underscore the multifaceted impact of neck pain on both ROM and proprioceptive function.

Neck pain is a common health problem in the community [36] and many patients apply to clinics several times a year for this problem. However, most of the time, the complaints of the patients do not go away and sometimes they become permanent. One of the important reasons for neck pain to become chronic is likely to be bad postural habits. On the other hand, it is known that bad posture causes pain [37]. We think that the fact that patients are not aware of their faulty postures due to their impaired proprioceptive sense is an important problem that complicates the treatment and causes the condition to become chronic. In our study, we observed that the proprioceptive sense of the cervical region and head posture were impaired in patients with neck pain. Perhaps impaired proprioception and body mechanics may be making recovery difficult in these patients. Therefore, we think that cervical proprioception and head posture should be considered in the pre-treatment evaluation of individuals with chronic neck pain. According to the results to be obtained, improvement of cervical proprioception and posture should also be considered in the treatment. Increasing proprioceptive awareness can help reduce stress on cervical structures along with a more normal body alignment [38].

Subgroup analyses were performed to determine whether diagnostic differences in patients with neck pain affected the results. However, we believe that the numerical differences between the subgroup populations should not be ignored. Additionally, the lack of detailed records regarding the discopathy levels of patients with disc problems, as well as the fact that the physical activity levels of all participants were not evaluated, are considered limitations of our study. For future studies, we recommend applying a uniform diagnostic approach, balancing subgroup populations, considering the physical activity levels of participants, and collecting more detailed diagnostic information.

5. Conclusion

In this study, we observed an increase in the angles of deviation of the head from the cardinal planes, and a significant deterioration in the joint position sense in individuals with chronic neck pain. Interventions to improve proprioception and correct posture should also be considered in the treatment of patients with neck pain.

Author contributions

All authors contributed equally to the development of the manuscript. Conception and design: KY, BSU, HG; Methodology: KY, OAS, BSU, HG; Investigation: KY, BSU, HG; Resources: OAS, BSU, HG; Data collecting: KY, BSU, HG; Analysis and interpretation of the data: KY, BSU, HG; Supervision: KY, OAS; Writing – original draft: KY, OAS, BSU, HG; Writing – review & editing: KY, OAS, BSU, HG. All authors read and approved the final version of the manuscript and agreed to the author ranking.

Data availability

The data associated with the paper are not publicly available but are available from the corresponding author upon reasonable request.

Ethical approval

This study was approved by the KTO Karatay University Faculty of Medicine Pharmaceutical and Non-Medical Devices Research Ethics Committee (Permission number $=$ 2020/015, Date: February 24, 2020).

Funding

The authors report no funding.

Informed consent

Written informed consent was obtained from all patients included in the study.

Footnotes

Acknowledgments

The authors would like to thank all study participants and Serkan Kuccukturk for his contribution to the statistical analysis.

Conflict of interest

The authors declare that they have no conflict of interest.

References

Alahmari

Reddy

Silvian

Ahmad

Nagaraj

Mahtab

. Influence of chronic neck pain on cervical joint position error (JPE): Comparison between young and elderly subjects. J Back Musculoskelet. 2017; 30(6): 1265-71.

Roijezon

Clark

Treleaven

. Proprioception in musculoskeletal rehabilitation. Part 1: Basic science and principles of assessment and clinical interventions. Man Ther. 2015; 20(3): 368-77.

Banks

. An allometric analysis of the number of muscle spindles in mammalian skeletal muscles. J Anat. 2006; 208(6): 753-68.

Proske

Gandevia

. The proprioceptive senses: their roles in signaling body shape, body position and movement, and muscle force. Physiol Rev. 2012; 92(4): 1651-97.

Amonoo-Kuofi

. The density of muscle spindles in the medial, intermediate and lateral columns of human intrinsic postvertebral muscles. J Anat. 1983; 136(Pt 3): 509-19.

Boyd-Clark

Briggs

Galea

. Muscle spindle distribution, morphology, and density in longus colli and multifidus muscles of the cervical spine. Spine (Phila Pa 1976). 2002; 27(7): 694-701.

Kulkarni

Chandy

Babu

. Quantitative study of muscle spindles in suboccipital muscles of human foetuses. Neurol India. 2001; 49(4): 355-9.

Peck

Buxton

Nitz

. A comparison of spindle concentrations in large and small muscles acting in parallel combinations. J Morphol. 1984; 180(3): 243-52.

Armstrong

McNair

Taylor

. Head and neck position sense. Sports Med. 2008; 38(2): 101-7.

10.

Paulus

Brumagne

. Altered interpretation of neck proprioceptive signals in persons with subclinical recurrent neck pain. J Rehabil Med. 2008; 40(6): 426-32.

11.

Maravita

Spence

Driver

. Multisensory integration and the body schema: Close to hand and within reach. Curr Biol. 2003; 13(13): R531-R9.

12.

Wolpert

Diedrichsen

Flanagan

. Principles of sensorimotor learning. Nat Rev Neurosci. 2011; 12(12): 739-51.

13.

Hillier

Immink

Thewlis

. Assessing Proprioception: A Systematic Review of Possibilities. Neurorehabil Neural Repair. 2015; 29(10): 933-49.

14.

Riemann

Lephart

. The sensorimotor system, part I: the physiologic basis of functional joint stability. J Athl Train. 2002; 37(1): 71-9.

15.

Sjolander

Michaelson

Jaric

Djupsjobacka

. Sensorimotor disturbances in chronic neck pain – range of motion, peak velocity, smoothness of movement, and repositioning acuity. Man Ther. 2008; 13(2): 122-31.

16.

Treleaven

Jull

Sterling

. Dizziness and unsteadiness following whiplash injury: characteristic features and relationship with cervical joint position error. J Rehabil Med. 2003; 35(1): 36-43.

17.

Malmstrom

Westergren

Fransson

Karlberg

Magnusson

. Experimentally induced deep cervical muscle pain distorts head on trunk orientation. Eur J Appl Physiol. 2013; 113(10): 2487-99.

18.

Haggard

Iannetti

Longo

. Spatial sensory organization and body representation in pain perception. Curr Biol. 2013; 23(4): R164-76.

19.

Moseley

Flor

. Targeting cortical representations in the treatment of chronic pain: a review. Neurorehabil Neural Repair. 2012; 26(6): 646-52.

20.

Reddy

Tedla

Dixit

Abohashrh

. Cervical proprioception and its relationship with neck pain intensity in subjects with cervical spondylosis. BMC Musculoskelet Disord. 2019; 20(1): 447.

21.

Rheault

Albright

Beyers

Franta

Johnson

Skowronek

, et al. Intertester reliability of the cervical range of motion device. J Orthop Sports Phys Ther. 1992; 15(3): 147-50.

22.

Youdas

Carey

Garrett

. Reliability of measurements of cervical spine range of motion – comparison of three methods. Phys Ther. 1991; 71(2): 98-104; discussion 5-6.

23.

Humphreys

. Cervical outcome measures: testing for postural stability and balance. J Manipulative Physiol Ther. 2008; 31(7): 540-6.

24.

Dumas

Arsenault

Boudreau

Magnoux

Lepage

Bellavance

, et al. Physical impairments in cervicogenic headache: traumatic vs. nontraumatic onset. Cephalalgia. 2001; 21(9): 884-93.

25.

Loudon

Ruhl

Field

. Ability to reproduce head position after whiplash injury. Spine (Phila Pa 1976). 1997; 22(8): 865-8.

26.

Uremovic

Cvijetic

Pasic

Seric

Vidrih

Demarin

. Impairment of proprioception after whiplash injury. Coll Antropol. 2007; 31(3): 823-7.

27.

Wibault

Vaillant

Vuillerme

Dedering

Peolsson

. Using the cervical range of motion (CROM) device to assess head repositioning accuracy in individuals with cervical radiculopathy in comparison to neck- healthy individuals. Manual Ther. 2013; 18(5): 403-9.

28.

Reid

Callister

Katekar

Rivett

. Effects of cervical spine manual therapy on range of motion, head repositioning, and balance in participants with cervicogenic dizziness: a randomized controlled trial. Arch Phys Med Rehabil. 2014; 95(9): 1603-12.

29.

Hawker

Mian

Kendzerska

French

. Measures of adult pain: Visual Analog Scale for Pain (VAS Pain), Numeric Rating Scale for Pain (NRS Pain), McGill Pain Questionnaire (MPQ), Short-Form McGill Pain Questionnaire (SF-MPQ), Chronic Pain Grade Scale (CPGS), Short Form-36 Bodily Pain Scale (SF-36 BPS), and Measure of Intermittent and Constant Osteoarthritis Pain (ICOAP). Arthritis Care & Research. 2011; 63(S11): S240-S52.

30.

Plichta

Kelvin

. Munro’s statistical methods for health care research. 6th ed. China: Lippincott Williams & Wilkins; 2013. pp. 1-563.

31.

Kennedy

. Therapeutic exercise for mechanical neck pain. In: Fernández de las Peñas

Cleland

Huijbregts

, editors. Neck and Arm Pain Syndromes. Edinburgh: Churchill Livingstone; 2011; pp. 185-200.

32.

Flor

. Cortical reorganisation and chronic pain: implications for rehabilitation. J Rehabil Med. 2003; (41 Suppl): 66-72.

33.

Thunberg

Hellstrom

Sjolander

Bergenheim

Wenngren

Johansson

. Influences on the fusimotor-muscle spindle system from chemosensitive nerve endings in cervical facet joints in the cat: possible implications for whiplash induced disorders. Pain. 2001; 91(1-2): 15-22.

34.

Stanton

Leake

Chalmers

Moseley

. Evidence of Impaired Proprioception in Chronic, Idiopathic Neck Pain: Systematic Review and Meta-Analysis. Phys Ther. 2016; 96(6): 876-87.

35.

Arimi

Ghamkhar

Kahlaee

. The Relevance of Proprioception to Chronic Neck Pain: A Correlational Analysis of Flexor Muscle Size and Endurance, Clinical Neck Pain Characteristics, and Proprioception. Pain Med. 2018; 19(10): 2077-88.

36.

Hogg-Johnson

van der Velde

Carroll

Holm

Cassidy

Guzman

, et al. The burden and determinants of neck pain in the general population – Results of the bone and joint decade 2000–2010 task force on neck pain and its associated disorders. Eur Spine J. 2008; 17: S39-S51.

37.

Yip

CHT

Chiu

TTW

Poon

ATK

. The relationship between head posture and severity and disability of patients with neck pain. Manual Ther. 2008; 13(2): 148-54.

38.

Jull

Falla

Treleaven

Hodges

Vicenzino

. Retraining cervical joint position sense: the effect of two exercise regimes. J Orthop Res. 2007; 25(3): 404-12.

Comparison of head posture and neck proprioceptive sense of individuals with chronic neck pain and healthy controls: A cross-sectional study

Abstract

BACKGROUND:

OBJECTIVE:

METHODS:

RESULTS:

CONCLUSION:

NOTE:

Keywords

1. Introduction

2. Methods

2.1 Study design

2.2 Participants

2.3 Sample size

2.4 Outcome measures

2.4.1 Primary outcomes: Head posture and joint position sense

2.4.3 Joint position error/head repositioning accuracy test

2.4.4 Pain severity

2.5 Data analysis

Table 1 Demographic data of the participants

3.1 Participants

3.2 Primary outcomes

3.2.1 Head Posture: The deviation angles of the head in three planes

Table 2 Comparison of the deviation angles of the head from all three planes

Table 4 The relationship between pain severity, head posture, and neck proprioceptive sense in individuals with neck pain

5. Conclusion

Author contributions

Data availability

Ethical approval

Funding

Informed consent

Footnotes

Acknowledgments

Conflict of interest

References

Table 1
Demographic data of the participants

Table 2
Comparison of the deviation angles of the head from all three planes

Table 4
The relationship between pain severity, head posture, and neck proprioceptive sense in individuals with neck pain