Torbjörn Ledin

Postural Control after Anterior Cruciate Ligament Reconstruction and Functional Rehabilitation

Total sagittal knee laxity and postural control in the sagittal and frontal planes were measured in 25 patients at a mean of 36 months (range, 27 to 44) after anterior cruciate ligament reconstruction and in a control group consisting of 20 uninjured age- and activity-matched subjects. Body sway was measured in the sagittal plane on a stable and on a sway-referenced force plate in single-legged stance, double-legged stance, or both, with the eyes open and closed. Postural reactions to perturbations in the sagittal and frontal planes were recorded in the single-legged stance with the eyes open. Total sagittal plane laxity was significantly greater in the anterior cruciate ligament-reconstructed knee (11.2 mm; range, 6 to 15) than in the uninjured knee (8.9 mm; range, 6 to 12) or in the control group (6.0 mm; range, 5 to 8). In spite of this, the patients, in comparison with the controls, exhibited normal postural control except in two variables—the reaction time and the latency between the start of force movement to maximal sway in the sagittal plane perturbations. This supports the hypothesis that rehabilitation, with proprioceptive and agility training, is an important component in restoring the functional stability in the anterior cruciate ligament-reconstructed knee.

Effects of postural disturbances with fatigued triceps surae muscles or with 20% additional body weight

One of the main issues for balance control is the ability to generate enough forces to execute motions and uphold stability. This study aimed to investigate whether induced fatigue of the triceps surae muscles and decreased muscle force due to temporary additional body weight affected the ability to withstand balance perturbations. Another aim was to examine whether postural control adaptation over time was able to compensate for the changes induced by fatigue and additional body weight. Eleven normal subjects were exposed to vibratory proprioceptive stimulation during three test conditions; a baseline test during normal condition; when the body weight was increased by 20%, by adding additional weight load; and when the triceps surae muscles were fatigued. The tests were performed both with eyes open and closed. The body movements were evaluated by analyzing the anteroposterior and lateral torques induced towards the supporting surface measured with a force platform. Postural control was substantially affected both by the additional body weight, and by muscle fatigue in the triceps surae muscles. The anteroposterior and lateral body sway were larger both with added weight and fatigued muscles compared with the baseline test during quiet stance. However, the body sway induced by the vibratory stimulation was significantly larger with additional body weight compared with when the triceps surae muscles were fatigued. The differences between the test conditions were mostly pronounced during tests with eyes closed and in the high frequency body sway (>0.1 Hz). Postural control adaptation was able to reduce but not fully compensate for the changes induced by fatigue and additional body weight. Several hypotheses could account for these observations. (1) Fatigued muscles are less sensitive to muscle vibration, (2) muscle fatigue alters the muscle contractile efficiency and thus alters the ability to produce high-frequency, short-latency responses to balance perturbations.

Postural stability using different neck positions in normal subjects and patients with neck trauma

Subjects with neck problems, such as whiplash injuries, often complain of disturbed equilibrium and, in some instances, provocation of the neck position can elicit such problems. The importance of neck proprioceptors for maintaining balance is gaining increased interest, moreover the function or malfunction of the otoliths may disturb equilibrium in certain head positions. The aim of the study was to create a reference material for postural control and its dependence on head position in healthy subjects and to compare this with a set of patients with known neck problems and associated vertiginous problems. A total of 32 healthy subjects (16 men, 16 women; age range 21-58 years) as well as 10 patients age range 27-62 years (mean 44 years) with neck problems and associated balance problems since a whiplash injury were tested for postural control using the EquiTest dynamic posturographic model. The normal subjects were initially split into four age groups in order to estimate the effects of age on performance. The postural stability was evaluated for dependence of support surface conditions (stable or sway-referenced), visual input (eyes open or closed) and head position (neutral, left rotated, right rotated, extended backwards or flexed forward) using analysis of variance (ANOVA) with Tukeys post hoc test in case of a significant factor effect. As expected, visual cues as well as stable support surface improve postural stability (p<0.001). Postural stability is statistically different in the head extended backwards condition compared with the other four head positions (p<0.001 in all cases) in both patients and controls. Eliminating this test condition from the analysis, only a slight (p<0.05) difference between head forwards and head turned left remained. This pattern of results remained if the normal subjects were only split into two age groups instead of four. Finally, the patient group exhibited significantly lower postural performance than all the groups of normal subjects (p<0.01), but none of the normal groups differed significantly from each other. It is concluded that the postural control system is significantly challenged in the head extended backwards condition in both normal subjects and patients with previous whiplash injury and persistent neck problems. The patient group differed statistically from all groups of normal subjects. This suggests that neck problems impair postural control, and that the head extended position is a more challenging task for the postural system to adapt to. Whether this is due to utricular malpositioning, central integrative functions or cervical proprioceptive afferents is not within the scope of this study to answer.Subjects with neck problems, such as whiplash injuries, often complain of disturbed equilibrium and, in some instances, provocation of the neck position can elicit such problems. The importance of neck proprioceptors for maintaining balance is gaining increased interest, moreover the function or malfunction of the otoliths may disturb equilibrium in certain head positions. The aim of the study was to create a reference material for postural control and its dependence on head position in healthy subjects and to compare this with a set of patients with known neck problems and associated vertiginous problems. A total of 32 healthy subjects (16 men, 16 women, age range 21-58 years) as well as 10 patients age range 27-62 years (mean 44 years) with neck problems and associated balance problems since a whiplash injury were tested for postural control using the EquiTest dynamic posturographic model. The normal subjects were initially split into four age groups in order to estimate the effects of age on performance. The postural stability was evaluated for dependence of support surface conditions (stable or sway-referenced), visual input (eyes open or closed) and head position (neutral, left rotated, right rotated, extended backwards or flexed forward) using analysis of variance (ANOVA) with Tukeys post hoc test in case of a significant factor effect. As expected, visual cues as well as stable support surface improve postural stability (p < 0.001). Postural stability is statistically different in the head extended backwards condition compared with the other four head positions (p < 0.001 in all cases) in both patients and controls. Eliminating this test condition from the analysis, only a slight (p < 0.05) difference between head forwards and head turned left remained. This pattern of results remained if the normal subjects were only split into two age groups instead of four. Finally, the patient group exhibited significantly lower postural performance than all the groups of normal subjects (p <0.01), but none of the normal groups differed significantly from each other. It is concluded that the postural control system is significantly challenged in the head extended backwards condition in both normal subjects and patients with previous whiplash injury and persistent neck problems. The patient group differed statistically from all groups of normal subjects. This suggests that neck problems impair postural control, and that the head extended position is a more challenging task for the postural system to adapt to. Whether this is due to utricular malpositioning, central integrative functions or cervical proprioceptive afferents is not within the scope of this study to answer.

Adenoid cystic carcinoma : Use of cell proliferation, BCL-2 expression, histologic grade, and clinical stage as predictors of clinical outcome

Although the three basic histologic growth patterns of adenoid cystic carcinomas (tubular, cribriform, and solid) provide some indication of clinical outcome, additional, perhaps superior, predictors of biologic activity are needed for patient management.

Reliability of clinical balance tests and subjective ratings in dizziness and disequilibrium

The aim was to assess (i) the test–retest and inter-rater reliability of, and (ii) the relationships between, commonly used clinical balance tests and subjective ratings in subjects with dizziness and disequilibrium. Fifty subjects (26 men and 24 women, mean age 63 years) with dizziness and disequilibrium following acute unilateral vestibular loss or central neurological dysfunction were tested with static and dynamic clinical balance tests, visual analogue scales (VAS), University of California Los Angeles Dizziness Questionnaire (UCLA-DQ), Dizziness Beliefs Scale (DBS), European Quality of Life questionnaire (EQ-5D), Dizziness Handicap Inventory (DHI), and Hospital Anxiety and Depression Scale (HADS). Most tests showed good test–retest and inter-rater reliability. Few correlations were seen between objective and subjective tests, but several correlations were found between the different subjective instruments. Sharpened Rombergs test eyes closed, standing on foam eyes closed, standing on one leg eyes open and walking in a figure-of-eight are recommended as reliable and appropriate clinical balance tests in subjects with dizziness and disequilibrium. Subjects with central lesions may have difficulties when rating their symptoms on VAS. Total scores rather than scores for separate items are recommended for UCLA-DQ and DHI.

Long-Term Improvement of Quality of Life as a Result of Tonsillotomy (With Radiofrequency Technique) and Tonsillectomy in Youths

Objective: This is a 1 year follow‐up to compare the effects of partial tonsil resection using the radiofrequency technique (RF) tonsillotomy (TT) with total tonsillectomy (TE) (blunt dissection). Obstructive symptoms, tendency for infections, and health‐related quality of life (HRQL) were studied and compared with the HRQL data from a normal population.

Effects of home training and additional physical therapy on recovery after acute unilateral vestibular loss- a randomized study

Objective: To evaluate the effects of additional physical therapy on recovery after acute unilateral vestibular loss given to patients receiving home training. Design: Randomized controlled trial. Setting: Ear, nose and throat departments in three hospitals. Subjects: Fifty-four patients (mean age 52 years) with acute unilateral vestibular loss within the last week confirmed with electronystagmography testing were included. Patients with central neurologic or auditory symptoms or other vertigo disease were excluded. Interventions: Home training with or without additional physical therapy 12 times during 10 weeks. Main measures: Electronystagmography testing was performed before and after the training period. Clinical static (Romberg?s test, sharpened Romberg?s test, standing on foam and standing on one leg) and dynamic (walking forward and backward on a line) balance tests and subjective ratings of vertigo and balance problems on a visual analogue scale were done one week, 10 weeks and six months after the start of training. Results: Similar changes were seen in the two training groups. Conclusions: No significant differences in outcome regarding balance function or perceived symptoms were found between home training with or without additional physical therapy.

Long-term follow-up after acute unilateral vestibular loss and comparison between subjects with and without remaining symptoms

Conclusions. About half of the subjects in this study reported remaining symptoms 3–6 years after acute unilateral vestibular loss. Differences could be seen between subjects with and without remaining symptoms regarding health-related quality of life, anxiety and depression. Objective. To evaluate the presence of self-rated remaining symptoms 3–6 years after acute unilateral vestibular loss, and to compare subjects with and without such symptoms. Material and methods. Firstly, 51 subjects answered a questionnaire which included the EuroQol EQ-5D, the Hospital Anxiety and Depression Scale, the University of California Los Angeles Dizziness Questionnaire, visual analogue scales and the Dizziness Handicap Inventory. Secondly, nine subjects with and nine without remaining symptoms participated in an extended testing procedure, including electronystagmography (ENG), determination of vestibular-evoked myogenic potentials (VEMPs) and clinical balance tests. Results. In the first part of the study, 27 subjects reported remaining symptoms, 3 reported 1 additional period of symptoms and 21 had not experienced any symptoms at all in the 3–6 years since acute unilateral vestibular loss. In the second part, the group with remaining symptoms rated a lower health-related quality of life and a higher level of anxiety and depression. There were no differences between the two groups in terms of ENG tests, VEMPs or clinical balance tests.

High incidence of pruritus after large doses of hydroxyethyl starch (HES) infusions.

Background: There are several studies indicating a correlation between treatment with hydroxyethyl starch (HES) and pruritus. In order to see whether there is a possible dose–response relationship between HES and pruritus, we retrospectively studied 50 patients who had received HES in varying doses (cumulative dose 500–19500 ml) as hemodilution therapy after subarachnoid hemorrhage.

Visual influence on postural control, with and without visual motion feedback

Body sway was investigated in 20 healthy subjects to determine whether visual input must contain motion feedback information from the surroundings in order to influence postural control. Posturography was used to record body sway under the following visual conditions: eyes open with or without a restricted visual field; eyes open in ganzfield white light; eyes open in darkness with a head-fixed visual target; eyes open in darkness; and eyes closed in darkness. Stance was perturbed by means of a pseudorandomly applied vibratory stimulation to the calf muscles. Least sway was found with eyes open in an unrestricted visual field but increased in a restricted visual field. Greatest sway was found without visual motion feedback, i.e. under the following conditions: eyes closed; eyes open in darkness; eyes open in ganzfield white light; and with a head-mounted fixation point. Sway was significantly ( p < 0.05) greater with eyes open in darkness compared with eyes closed during the initial 50 s with perturbations. After 150 s, sway was almost identical under the four test conditions without visual motion feedback. Standing with eyes open in darkness was initially a disadvantage compared with having the eyes closed. The postural control system may be programmed to expect visual feedback information when the eyes are open, which may delay changes in postural strategy.