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Dive into the research topics where Gillian M. Johnson is active.

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Featured researches published by Gillian M. Johnson.


Spine | 1998

The correlation between surface measurement of head and neck posture and the anatomic position of the upper cervical vertebrae.

Gillian M. Johnson

Study Design. Repeated measurements were made of surface postural angles registering the relative positions of the head and neck in photographs and of angles of the upper cervical vertebrae recorded in lateral cephalometric radiographs in the same subjects. For all registrations, subjects assumed the natural head rest position. Objectives. To examine the correlation between external measurement of head and neck posture and the anatomic positions of the upper four cervical vertebrae. Summary of Background Data. Interpretation of surface cervical posture measurement is confounded by lack of knowledge about the extent of the underlying compensatory adjustments among the upper cervical vertebrae that may accompany variation in head and neck posture. The correlation between surface measurement and postural characteristics of the upper cervical spine has not been reported to date. Methods. The association between a set of angles describing the anatomic position of the four upper cervical vertebrae on lateral cephalometric radiographs and a surface measurement of head and neck posture, the craniovertebral angle, was studied in 34 young adult women aged between 17.2 and 30.5 years, mean age, 24.5 years. Anatomic positions of the upper four cervical vertebrae were expressed by angles relative to the true vertical or horizontal. Surface angles registering head and neck position for each subject were obtained from photographs recorded on two occasions. Results. No strong correlation could be established between the angles taken from the lateral cephalometric radiographs measuring the extent of upper cervical lordosis, orientation of the atlas, vertebral inclination, or odontoid process tilt and surface angles recording head and neck position. This finding was attributed principally to the much greater positional variability demonstrated within the upper cervical spine when compared with the surface measurements of head and neck position. Conclusion. Anatomic alignment of the upper cervical vertebrae cannot be inferred from variation in surface measurement of head and neck posture. This is the case even in those people identified with more extreme head and neck postural tendencies.


Spine | 2000

The fine connective tissue architecture of the human ligamentum nuchae.

Gillian M. Johnson; Ming Zhang; David Gareth Jones

Study Design. An anatomic study of the posterior midline structures of the cervical spine was performed using a new sheet-plastination (E12) technique in conjunction with gross anatomic dissection. Objectives. To clarify the structural status of the human ligamentum nuchae. Summary of Background Data. Little is known about the arrangement of connective tissue attachments of the neighboring neck muscles to the ligamentum nuchae. In addition, it is not clear whether the cervical supraspinous ligaments form part of the ligamentum nuchae. Methods. This study used a combined approach of a detailed gross anatomic study on eight cadavers and a macroscopic and microscopic study of the connective tissue organization of the posterior midline structures on serial horizontal thin (2.5 mm) plastinated slices of the cervical spine (occiput–T1) from an adult female cadaver. Results. The dorsal and ventral portions of the ligamentum nuchae are a single entity formed by the aponeurotic fibers of the trapezius, splenius capitis, rhomboideus minor, and serratus posterior superior muscles. Conclusions. The regional differences in the connective tissue organization of the ligamentum nuchae and its well-defined attachments to the C6 and C7 vertebrae suggest that it is designed to function in the lower cervical spine.


Spine | 2005

Configuration of the connective tissue in the posterior atlanto-occipital interspace: a sheet plastination and confocal microscopy study.

Lance Nash; Helen D. Nicholson; Antonio S. J. Lee; Gillian M. Johnson; Ming Zhang

Study Design. The connective tissue structures in the posterior atlanto-occipital region were investigated using E12 sheet plastinations and confocal microscopy. Objectives. To define the relationship between rectus capitis posterior minor (RCPm), posterior atlanto-occipital (PAO) membrane, nuchal ligament, and the spinal dura in the PAO interspace. Summary of Background Data. It has been speculated that connections between the dura and muscles and/or ligaments in the PAO interspace may transmit forces from the cervical spine joint complexes to the pain-sensitive dura, generating cervicogenic headaches. Anatomic structures involved in these connections include the RCPm, PAO membrane, and nuchal ligament. However, there is little information about the nature of these connections and the relationships between these anatomic structures. Methods. The study used a combined approach, consisting of the gross anatomic dissection of nine cadavers and the E12 sheet plastination method for thirteen adult human cadavers, five of which were further examined using confocal microscopy. Results. The study demonstrates that (1) the tendinous fibers from the medial and deep part of the RCPm muscle are continuous antero-inferiorly with the spinal dura; (2) the PAO membrane is part of the RCPm fascia and tendon and the perivascular sheathes; (3) antero-inferiorly the PAO membrane fuses with the spinal dura rather than the atlas; and (4) the nuchal ligament does not exist in the PAO interspace. Conclusions. The connective tissue structures that connect the spinal dura to the RCPm muscle in the PAO interspace are the RCPm fascia and tendinous fibers and perivascular sheathes.


Spine | 2010

Changes in head and neck posture using an office chair with and without lumbar roll support.

Stuart J. Horton; Gillian M. Johnson; Margot Skinner

Study Design. A repeated measures observational study. Objective. To investigate change in sagittal alignment of head and neck posture in response to adjustments of an office chair with and without a lumbar roll in situ. Summary of Background Data. Forward head posture has been identified as a risk factor for neck pain, and there is evidence to show that ergonomic correction in sitting may reduce the incidence of pain. The effect placement of a lumbar roll has on cervical spine posture has not been previously investigated experimentally but rather, is assumed to have a positive influence on head and neck posture. Methods. Thirty healthy male participants (18–30 years) were photographed while registered in the natural head resting position in each of 4 sitting positions with and without a lumbar roll in situ. Two positions incorporated adjustments to the back rest and 1 to the seat pan of the office chair. The craniovertebral (CV) angle, as a determinant of head and neck posture was measured from the set of digitized photographs obtained for each participant. Comparisons between the CV angle in all postural registrations were made using a mixed model analysis adjusted for multiple comparisons. Results. Of the positions examined, significant differences in the mean CV angles were found with the backrest of the chair at 100° and at 110° (P < 0.001). With the lumbar roll in situ and the backrest position at 110°, there was a significant increase in the mean CV compared with the angle without the lumbar roll in situ (2.32°, 95% confidence interval: 1.31–3.33; P < 0.001). Conclusion. The degree of angulation of the backrest support of an office chair plus the addition of lumbar roll support are the 2 most important factors to be taken into account when considering seating factors likely to favorably change head and neck postural alignment, at least in asymptomatic subjects.


Manual Therapy | 2004

The sensory and sympathetic nerve supply within the cervical spine: review of recent observations

Gillian M. Johnson

The purpose of this review is to identify recently observed features of the sympathetic and sensory systems and their pathways which characterize cervical spine innervation and their potential relevance to the clinical pain syndromes. The results of studies examining the innervation patterns of the zygoapophysial joints serve to demonstrate that structures in the cervical spine, as in other spinal regions, are partly innervated by sensory nerves traveling along sympathetic pathways. These studies also demonstrate that the neuropeptide levels in the cell bodies located within the dorsal root ganglion of these sensory nerves fluctuate according to the physiological state of the zygoapophysial joint. Additional to the sympathetic nerves accompanying the vertebral artery, the innervation patterns of dura and posterior longitudinal ligament in the upper cervical spine are distinctive features of cervical spine innervation. The possible clinical implications of cervical innervation patterns are considered with reference to referred pain, the pain patterns associated with a dissecting vertebral artery and cervicogenic headaches.


European Spine Journal | 2002

Regional differences within the human supraspinous and interspinous ligaments: a sheet plastination study

Gillian M. Johnson; Ming Zhang

Abstract. The extent to which neighboring muscles and the fascia contribute to the formation of the supraspinous and interspinous ligaments is not clear from the literature. The purpose of this investigation is to examine the midline attachments of tendons and the posterior layer of thoracolumbar fascia in order to determine their respective contributions to the formation of these ligaments throughout the thoracolumbar spine. Study of the dense connective tissue organization in the posterior ligamentous system was carried out on two cadavers serially sectioned into thin (2.5-mm) epoxy resin plastinated slices. Additional observations were taken from a gross anatomical study of the midline anatomy in two adult cadavers. The results show that the spinal attachments of trapezius, rhomboideus major and splenius cervicis combine with the deep fascia to form the supraspinous ligament in the upper thoracic spine. The posterior layer of the thoracolumbar fascia makes a major contribution to the supraspinous and interspinous ligaments in the lower thoracic spine. In addition to the posterior layer of thoracolumbar fascia, longissimus thoracis and multifidus combine to form the lumbar supraspinous and interspinous ligaments. Their spinal attachments produce a system of dense connective tissue with marked regional variation in fiber orientation and arrangement. The findings support the description of the supraspinous and interspinous ligaments as structures formed by both muscle tendons and aponeuroses along the length of the thoracic and lumbar spine, with regional differences in their connective tissue architecture.


International Journal of Rehabilitation Research | 2012

Instrumented Measurement of Balance and Postural Control in Individuals with Lower Limb Amputation: A Critical Review.

Prasath Jayakaran; Gillian M. Johnson; S. John Sullivan; Jennifer C. Nitz

Measurement of balance and postural performance that underpins activities of daily living is important in the rehabilitation of individuals with a lower limb amputation (LLA), and there are a number of methods and strategies available for this purpose. To provide an evidence-based choice of approach, this review aims to critically review the tasks and outcome measures utilized in studies investigating static and dynamic balance using instrumented measurement devices in individuals with a LLA. A systematic search was conducted on multiple databases using keyword or subject headings appropriate to the respective database. Articles investigating static or dynamic balance in adults with LLA by means of instrumented measures were considered for the review. A total of 21 articles were included in the review. The static balance ability of individuals with an LLA has been investigated thoroughly, but their dynamic balance attributes remain relatively unexplored. Although the individual studies do provide valuable information on balance ability in the LLA, the heterogeneity in study designs and measures did not allow an overall analysis of the tasks and the outcome measures used. On the basis of these findings, this review provides an insight into the measurement of balance in amputees to inform novice researchers and clinicians working with individuals with an LLA.


Pm&r | 2011

Test-Retest Reliability of the Sensory Organization Test in Older Persons With a Transtibial Amputation

Prasath Jayakaran; Gillian M. Johnson; S. John Sullivan

To determine the test‐retest reliability of the Sensory Organization Test (SOT) in older persons with a unilateral transtibial amputation.


BMC Musculoskeletal Disorders | 2012

Radiographic knee osteoarthritis in ex-elite table tennis players

Reza Rajabi; Gillian M. Johnson; Mohammad Hossein Alizadeh; Nazanin Meghdadi

BackgroundTable tennis involves adoption of the semi-flexed knee and asymmetrical torsional trunk movements creating rotational torques on the knee joint which may predispose players to osteoarthritis (OA) of the knee. This study aims to compare radiographic signs of knee OA and associated functional levels in ex-elite male table tennis players and control subjects.MethodsStudy participants were 22 ex-elite male table tennis players (mean age 56.64 ± 5.17 years) with 10 years of involvement at the professional level and 22 non-athletic males (mean age 55.63 ± 4.08 years) recruited from the general population. A set of three radiographs taken from each knee were evaluated by an experienced radiologist using the Kellgren and Lawrence (KL) scale (0-4) to determine radiographic levels of OA severity. The intercondylar distance was taken as a measure of lower limb angulation. Participants also completed the pain, stiffness, and physical function categories of the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) 3.1 questionnaire.ResultsThe results showed 78.3% of the ex-elite table tennis players and 36.3% of controls had varying signs of radiographic knee OA with a significant difference in the prevalence levels of definite radiographic OA (KL scale > 2) found between the two groups (P ≤ 0.001). Based on the WOMAC scores, 68.2% of the ex-elite table tennis players reported symptoms of knee pain compared with 27.3% of the controls (p = 0.02) though no significant differences were identified in the mean physical function or stiffness scores between the two groups. In terms of knee alignment, 73.7% of the ex-elite athletes and 32% of the control group had signs of altered lower limb alignment (genu varum) (p = 0.01). Statistical differences were found in subjects categorized as having radiographic signs of OA and altered lower limb alignment (p = 0.03).ConclusionsEx-elite table tennis players were found to have increased levels of radiological signs of OA in the knee joint though this did not transpire through to altered levels of physical disability or knee stiffness in these players when compared with subjects from the general population suggesting that function in these players is not severely impacted upon.


Archives of Physical Medicine and Rehabilitation | 2015

Postural Control in Response to Altered Sensory Conditions in Persons With Dysvascular and Traumatic Transtibial Amputation

Prasath Jayakaran; Gillian M. Johnson; S. John Sullivan

OBJECTIVE To compare the postural control of persons with a dysvascular transtibial amputation and traumatic transtibial amputation with able-bodied adults with and without a dysvascular condition in altered sensory testing conditions. DESIGN Cross-sectional study. SETTING University balance clinic. PARTICIPANTS The study participants (N=35) included: participants with a dysvascular transtibial amputation (n=9), participants with a traumatic transtibial amputation (n=9), age-matched able-bodied adults without a dysvascular condition (n=9), and able-bodied adults with a dysvascular condition (n=8). INTERVENTIONS Six Sensory Organization Test (SOT) conditions, which included standing with eyes open (condition 1) and closed (condition 2) on a static force platform with visual surround; standing with eyes open on a static force platform with movable visual surround (condition 3); standing with eyes open (condition 4) and closed (condition 5) on a movable force platform with static visual surround; and standing with eyes open on a movable force platform with movable visual surround (condition 6). MAIN OUTCOME MEASURES Bilateral anteroposterior (AP) and mediolateral (ML) center of pressure variables, namely root mean square distance (RMSD) and mean velocity (mVel), for each of the 6 SOT conditions. RESULTS The dysvascular transtibial amputation group demonstrated a higher AP RMSD (P≤.04) on the sound side than did the able-bodied adults without a dysvascular condition and the able-bodied adults with a dysvascular condition in SOT conditions 1 and 2, respectively. Both the dysvascular transtibial amputation group and the traumatic transtibial amputation group demonstrated a higher AP RMSD (P≤.002) than the able-bodied adults without a dysvascular condition in SOT conditions 3 and 4. The dysvascular transtibial amputation group showed higher AP mVel (P≤.002) on the sound side for SOT conditions 2 and 3, whereas both amputation groups showed higher AP mVel for SOT conditions 1 and 4 than the able-bodied adults with and without a dysvascular condition. CONCLUSIONS Postural control of the dysvascular transtibial amputation group was not different than the traumatic transtibial amputation group in challenging sensory conditions. However, when compared with the groups of able-bodied adults with and without a dysvascular condition, postural strategies distinct with amputation etiology were observed.

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