Background
Methods
Healthy control group (HC)
Neck pain group (NP)
Questionnaire data
Instrumentation and sensors
Construct | Test | Assessment | Unit of measure | Sensors | Reps per test | Analyzed | Comments |
---|---|---|---|---|---|---|---|
Neck flexibility | Active neck movements in flexion/extension, rotation and lateral flexion | Cervical ROM in flexion/extension, rotation, and, lateral flexion | deg | S1 vs S2 | 3 | Avg | Full cycle cervical ROM |
Conjunct motion in the two associated movement planes | deg | Avg | According to Woodhouse et al. (2008) | ||||
Peak velocity in flexion/extension, rotation and lateral flexion | deg/s | Avg | 3 D angular velocity | ||||
Proprioception | Joint position error in left and right head rotation | 3D repositioning error in left and right rotation | deg | S1 vs S2 | 6 | Avg | 3 repetitions in each direction |
Trajectory movement control | FOE slow speed | Average point deviation (PD) | cm | S1 vs TX | 1 | Single | 30 sec duration |
FOE fast speed | 1 | 20 sec duration | |||||
FOE in standing, slow speed | 1 | 30 sec duration. | |||||
The Fly test, 1A | Average point deviation (PD) | cm | S1 vs TX | 1 | Single | 30 sec duration for all of the Fly tests. Adopted from Kristjansson et al. (2010) | |
The Fly test, 2B | 1 | ||||||
The Fly test, 1B | 1 | ||||||
The Fly test, 2A | 1 | ||||||
Head steadiness | Isometric neck flexion, low load | Average 3 D angular velocity | deg/s | S1 vs S2 | 1 | Single | 60 sec duration 60° recumbent position |
Isometric neck flexion, high load | Average 3 D angular velocity | deg/s | 1 | 30 sec duration Supine position | |||
Holding time | sec | ||||||
Postural sway | Standing balance EO | Sway area (95 % confidence area) | cm2 | S3 vs TX | 1 | Single | 60 sec duration for the tests of standing balance. |
Standing balance EC | 1 | ||||||
Standing balance EOB | 1 | ||||||
FOE in standing | 1 | 30 sec duration |
Outcome variables and testing procedures
Neck pain patients n = 75 | Healthy controls n = 91 | p | |
---|---|---|---|
Age | 43.1 (12.9) | 40.8 /13.8) | 0.28 |
Gender (male/female | 20/55 | 43/48 | 0.01 |
Body mass index | 24.9 (4.7) | 25.0 (3.5) | 0.9 |
Current neck pain (NRS: 0-10) | 4.6 (1.4) | N/A | |
Worst neck pain last month (NRS: 0-10) | 7.4 (1.5) | N/A | |
Duration of neck pain, n (%) | N/A | ||
< 3 months | 7 (9%) | ||
3-6 months | 13 (17%) | ||
> 6 months | 55 (74%) | ||
Neck Disability Index (0-100) | 31.2 (11.6) | N/A | |
TSK (13-52) | 24.4 (4.3) | N/A | |
PCS (0-52) | 12.9 (8.5) | N/A | |
PSEQ (0-60) | 44.3 (10.0) | N/A | |
Concurrent low back pain, n (%) | 20 (27%) | N/A | |
Self-rated general health, n (%) | N/A | ||
Poor | 0 (0) | ||
Fair | 36 (48%) | ||
Good | 37 (49%) | ||
Very good | 2 (3%) | ||
Frequency physical activity, n(%) | N/A | ||
< once per week | 10 (12%) | ||
1-3 days per week | 51 (68%) | ||
4-7 days per week | 14 (19) | ||
Use of analgesica, n (%) | 38 (51) | N/A |
Neck flexibility
Proprioception
Trajectory movement control
Head steadiness
Postural sway
Statistical analysis
Neck pain (n = 75) | Healthy controls (n = 91) | p | |
---|---|---|---|
Neck flexibility
| |||
Flexion/extension (°)
1
| 110.1 (105.7-114.5) | 126.2 (122.3-130.2) | <0.01 |
CM (°)1 | 12.3 (11.3-13.3) | 16.5 (15.6-17.4) | <0.01 |
CM (°)2 | 12.9 (11.9-14.0) | 16.0 (15.1-16.9) | <0.01 |
CM (°)3 | 13.7 (12.4-15.0) | 15.4 (14.4-16.3) | 0.03 |
Peak velocity (°/s)1 | 70.6 (62.5-78.7) | 115.6 (108.4-122.8) | <0.01 |
Peak velocity (°/s)2 | 75.0 (66.8- 83.1) | 112.1 (104.9-119.4) | <0.01 |
Rotation (°)
1
| 128.2 (124.3-132.2) | 140.7 (137.2-144.2) | <0.01 |
CM (°)1 | 19.8 (18.0-21.6) | 25.1 (23.5-26.7) | <0.01 |
CM (°)2 | 20.6 (18.7-22.4) | 24.5 (22.8-26.1) | <0.01 |
CM (°)3 | 21.1 (19.2-23.1)) | 24.0 (22.3-25.7) | 0.04 |
Peak velocity (°/s)1 | 109.3 (98.9-119.7) | 158.9 (149.6-168.3) | <0.01 |
Peak velocity (°/s)2 | 114.3 (103.9-124.7) | 154.9 (145.7-164.2) | <0.01 |
Lateral flexion (°)
1
| 68.1 (64.7-71.6) | 72.6 (69.5-75.7) | 0.06 |
CM (°)1 | 45.7 (40.1-51.3) | 62.5 (57.5-67.5) | <0.01 |
CM (°)2 | 44.9 (39.4- 50.5) | 63.1 (58.1-68.0) | <0.01 |
CM (°)3 | 52.7 (47.6-57.7) | 56.9 (52.4-61.4) | 0.25 |
Peak velocity (°/s)1 | 57.9 (52.2-63.5) | 85.7 (80.6-90.7) | <0.01 |
Peak velocity (°/s)2 | 58.6 (53.0- 64.2) | 85.1 (80.1-90.1) | <0.01 |
Total cervical ROM (°)
1
| 306.5 (296.5-316.5) | 339.5 (330.6-348.5) | <0.01 |
Proprioception
| |||
JPE (°)2 | 5.6 (5.2-6.1) | 5.1 (4.6-5.5) | 0.11 |
Neck pain | Healthy controls | n=NP/HC | p1 | |
---|---|---|---|---|
Head steadiness
| ||||
INF Low load
| ||||
Angular velocity (°/s) | 1.3 (1.2-1.4) | 1.7 (1.6-1.8) | 75/90 | <0.01 |
INF High Load
| ||||
Angular velocity (°/s) | 2.8 (2.6-2.9) | 4.5 (4.3-4.7) | 73/91 | <0.01 |
Trajectory movement control
| ||||
FOE Low speed
| ||||
Point deviation (cm) | 3.4 (3.1-3.7) | 3.8 (3.4-4.1) | 75/89 | 0.17 |
FOE High speed
| ||||
Point deviation (cm) | 4.4 (4.1-4.8) | 5.2 (4.8-5.6) | 75/91 | <0.01 |
FOE Standing, low speed
| ||||
Point deviation (cm) | 2.9 (2.6-3.1) | 3.3 (3.0-3.6) | 74/91 | 0.02 |
The Fly test
| ||||
PD test 1A (cm) | 2.2 (2.0-2.4) | 2.5 (2.3-2.7) | 75/89 | 0.03 |
PD test 1B (cm) | 2.1 (2.0-2.2) | 2.1 (2.0-2.3) | 75/89 | 0.63 |
PD test 2A (cm) | 3.1 (2.9-3.3) | 3.3 (3.1-3.5) | 74/88 | 0.33 |
PD test 2B (cm) | 2.8 (2.7-3.0) | 2.8 (2.6-2.9) | 75/83 | 0.64 |
Postural sway
| ||||
Sway area EO (cm2) | 3.0 (2.4-3.5) | 2.7 (2.2-3.3) | 72/90 | 0.53 |
Sway area EC (cm2) | 2.5 (2.0-3.1) | 2.0 (1.7-2.3) | 72/87 | 0.12 |
Sway area EOB (cm2) | 11.0 (9.7-12.3) | 8.1 (7.4-8.7) | 73/91 | <0.01 |
Sway area FOE (cm2) | 4.3 (3.3-5.2) | 5.9 (4.2-7.5) | 73/48 | 0.09 |
Results
Neck flexibility
Proprioception
Head steadiness
Indicate less motion | Normal | Indicate larger motion | Effect size Mean (95 % CI) | |
---|---|---|---|---|
Neck flexibility
| ||||
Flexion/extension
1
| X | 0.84 (0.52 to 1.16)* | ||
CM3 | X | 0.37 (0.06 to 0.68)* | ||
Peak velocity2 | X | 1.05 (0.72 to 1.37)* | ||
Rotation
1
| X | 0.72 (0.41 to 1.04)* | ||
CM3 | X | 0.36 (0.05 to 0.67)* | ||
Peak velocity2 | X | 0.90 (0.57 to 1.22)* | ||
Lateral flexion
1
| X | 0.30 (-0.01 to 0.61) | ||
CM3 | X | 0.19 (-0.11 to 0.50) | ||
Peak velocity2 | X | 1.08 (0.75 to 1.41)* | ||
Total cervical ROM
1
| X | 0.76 (0.44 to 1.08)* | ||
Proprioception
| ||||
JPE2 | X | -0.26 (-0.56 to 0.05) | ||
Head steadiness
| ||||
Low load1 | X | 1.29 (0.95 to 1.63)* | ||
High Load1 | X | 1.95 (1.58 to 2.32)* | ||
Trajectory movement control
| ||||
FOE low speed1 | X | 0.22 (-0.09 to 0.53) | ||
FOE high sped1 | X | 0.45 (0.13 to 0.76)* | ||
FOE standing1 | X | 0.40 (0.09 to 0.71)* | ||
Fly test 1A1 | X | 0.36 (0.05 to 0.68)* | ||
Fly test 1B1 | X | 0.07 (-0.23 to 0.38 | ||
Fly test 2A1 | X | 0.16 (-0.15 to 0.47) | ||
Fly test 2B1 | X | -0.07 (-0.39 to 0.24) | ||
Postural sway
| ||||
Open eyes1 | X | -0.09 (-0.40 to 0.21) | ||
Closed eyes1 | X | -0.26 (-0.57 to 0.06) | ||
Balance pad1 | X | -0.64 (-0.95 to -0.32)* | ||
FOE standing1 | X | 0.30 (-0.07 to 0.66) |
Trajectory movement control
Postural sway
Associations between clinical features and constructs of motor control
Variables | NPRS r | NDI r | Duration1rho | TSK r |
---|---|---|---|---|
Neck flexibility
| ||||
Flexion/extension |
-0.36**
| -0.10 | -0.09 | -0.11 |
Conjunct motion |
-0.26*
| 0.05 | -0.09 | 0.12 |
Peak velocity |
-0.34**
| -0.21 | -0.14 |
0.231*
|
Proprioception
| ||||
Joint position error | 0.01 | 0.147 | 0.03 | 0.12 |
Head steadiness
| ||||
INF low load | -0.1 | -0.13 | -0.11 | -0.11 |
INF high load | 0.05 | -0.12 | -0.05 | -0.06 |
Trajectory movement control
| ||||
PD FOE fast | 0.18 | 0.09 | -0.14 | -0.02 |
PD Fly test2 | 0.19 |
0.27*
| -0.21 | -0.10 |
Postural sway
| ||||
Area EOB | 0.03 | -0.04 | 0.14 | -0.07 |