Extension and flexion in the upper cervical spine in neck pain patients.

Neck pain is a common problem in the general population with high risk of ongoing complaints or relapses. Range of motion (ROM) assessment is scientifically established in the clinical process of diagnosis, prognosis and outcome evaluation in neck pain. Anatomically, the cervical spine (CS) has been considered in two regions, the upper and lower CS. Disorders like cervicogenic headache have been clinically associated with dysfunctions of the upper CS (UCS), yet ROM tests and measurements are typically conducted on the whole CS. A cross-sectional study assessing 19 subjects with non-specific neck pain was undertaken to examine UCS extension-flexion ROM in relation to self-reported disability and pain (via the Neck Disability Index (NDI)). Two measurement devices (goniometer and electromagnetic tracking) were employed and compared. Correlations between ROM and the NDI were stronger for the UCS compared to the CS, with the strongest correlation between UCS flexion and the NDI-headache (r = -0.62). Correlations between UCS and CS ROM were fair to moderate, with the strongest correlation between UCS flexion and CS extension ROM (r = -0.49). UCS flexion restriction is related to headache frequency and intensity. Consistency and agreement between both measurement systems and for all tests was high. The results demonstrate that separate UCS ROM assessments for extension and flexion are useful in patients with neck pain.

Low back pain and postural control, effects of task difficulty on centre of pressure and spinal kinematics.

Association of low back pain and standing postural control (PC) deficits are reported inconsistently. Demands on PC adaptation strategies are increased by restraining the input of visual or somatosensory senses. The objectives of the current study are, to investigate whether PC adaptations of the spine, hip and the centre of pressure (COP) differ between patients reporting non-specific low back pain (NSLBP) and asymptomatic controls. The PC adaption strategies of the thoracic and lumbar spine, the hip and the COP were measured in fifty-seven NSLBP patients and 22 asymptomatic controls. We tested three "feet together" conditions with increasing demands on PC strategies, using inertial measurement units (IMUs) on the spine and a Wii balance board for centre of pressure (COP) parameters. The differences between NSLBP patients and controls were most apparent when the participants were blindfolded, but remaining on a firm surface. While NSLBP patients had larger thoracic and lumbar spine mean absolute deviations of position (MADpos) in the frontal plane, the same parameters decreased in control subjects (relative change (RC): 0.23, 95% confidence interval: 0.03 to 0.45 and 0.03 to 0.48). The Mean absolute deviation of velocity (MADvel) of the thoracic spine in the frontal plane showed a similar and significant effect (RC: 0.12 95% CI: 0.01 to 0.25). Gender, age and pain during the measurements affected some parameters significantly. PC adaptions differ between NSLBP patients and asymptomatic controls. The differences are most apparent for the thoracic and lumbar parameters of MADpos, in the frontal plane and while the visual condition was removed.

Effects of simulated crouch gait on foot kinematics and kinetics in healthy children.

Identification of secondary and tertiary impairments in neurologically induced gait deviations, such as crouch gait, is not always straightforward, but essential in order to decide upon the most efficient medical treatment in patients with cerebral palsy (CP). Until now, exact intersegmental dependency of the development of foot deformities has not been investigated. Therefore, the aim of this study was to explore if an artificially induced bilateral knee flexion contracture causes compensatory mechanisms in foot motion during gait in healthy children. Three-dimensional kinematic and kinetic data from 30 healthy children (mean age 10.6 years) were derived from the Oxford Foot model (OFM). Participants walked first in an artificially induced crouch gait (limitation of knee extension to 40°) and then normally. Walking speed was kept the same in both conditions. Analysis revealed small but significant (p<0.05) differences between the two conditions in hindfoot and forefoot kinematics in all three planes during the stance phase as well as for all peak internal moments within the foot. In general the foot tended to compensate for an artificial knee flexion contracture with an increase in maximal dorsiflexion, eversion and external rotation of the hindfoot, which also allowed increased foot motion in other foot segments. The results of this study showed that an isolated proximal joint contracture had an influence on foot position during stance in healthy children. Further interpretation of the data in relation to CP children will be possible as soon as comparable OFM data of pathological crouch gait is available.