SIAMOC position paper on gait analysis in clinical practice: General requirements, methods and appropriateness. Results of an Italian consensus conference

Gait analysis is recognized as a useful assessment tool in the field of human movement research. However, doubts remain on its real effectiveness as a clinical tool, i.e. on its capability to change the diagnostic-therapeutic practice. In particular, the conditions in which evidence of a favorable cost-benefit ratio is found and the methodology for properly conducting and interpreting the exam are not identified clearly. To provide guidelines for the use of Gait Analysis in the context of rehabilitation medicine, SIAMOC (the Italian Society of Clinical Movement Analysis) promoted a National Consensus Conference which was held in Bologna on September 14th, 2013. The resulting recommendations were the result of a three-stage process entailing i) the preparation of working documents on specific open issues, ii) the holding of the consensus meeting, and iii) the drafting of consensus statements by an external Jury. The statements were formulated based on scientific evidence or experts' opinion, when the quality/quantity of the relevant literature was deemed insufficient. The aim of this work is to disseminate the consensus statements. These are divided into 13 questions grouped in three areas of interest: 1) General requirements and management, 2) Methodological and instrumental issues, and 3) Scientific evidence and clinical appropriateness. SIAMOC hopes that this document will contribute to improve clinical practice and help promoting further research in the field.

Adaptation of feedforward movement control is abnormal in patients with cervical dystonia and tremor

OBJECTIVE

It is under debate whether the cerebellum plays a role in dystonia pathophysiology and in the expression of clinical phenotypes. We investigated a typical cerebellar function (anticipatory movement control) in patients with cervical dystonia (CD) with and without tremor.

METHODS

Twenty patients with CD, with and without tremor, and 17 healthy controls were required to catch balls of different load: 15 trials with a light ball, 25 trials with a heavy ball (adaptation) and 15 trials with a light ball (post-adaptation). Arm movements were recorded using a motion capture system. We evaluated: (i) the anticipatory adjustment (just before the impact); (ii) the extent and rate of the adaptation (at the impact) and (iii) the aftereffect in the post-adaptation phase.

RESULTS

The anticipatory adjustment was reduced during adaptation in CD patients with tremor respect to CD patients without tremor and controls. The extent and rate of adaptation and the aftereffect in the post-adaptation phase were smaller in CD with tremor than in controls and CD without tremor.

CONCLUSION

Patients with cervical dystonia and tremor display an abnormal predictive movement control.

SIGNIFICANCE

Our findings point to a possible role of cerebellum in the expression of a clinical phenotype in dystonia.

Comparative assessment of different methods for the estimation of gait temporal parameters using a single inertial sensor: application to elderly, post-stroke, Parkinson's disease and Huntington's disease subjects

The estimation of gait temporal parameters with inertial measurement units (IMU) is a research topic of interest in clinical gait analysis. Several methods, based on the use of a single IMU mounted at waist level, have been proposed for the estimate of these parameters showing satisfactory performance when applied to the gait of healthy subjects. However, the above mentioned methods were developed and validated on healthy subjects and their applicability in pathological gait conditions was not systematically explored. We tested the three best performing methods found in a previous comparative study on data acquired from 10 older adults, 10 hemiparetic, 10 Parkinson's disease and 10 Huntington's disease subjects. An instrumented gait mat was used as gold standard. When pathological populations were analyzed, missed or extra events were found for all methods and a global decrease of their performance was observed to different extents depending on the specific group analyzed. The results revealed that none of the tested methods outperformed the others in terms of accuracy of the gait parameters determination for all the populations except the Parkinson's disease subjects group for which one of the methods performed better than others. The hemiparetic subjects group was the most critical group to analyze (stride duration errors between 4-5 % and step duration errors between 8-13 % of the actual values across methods). Only one method provides estimates of the stance and swing durations which however should be interpreted with caution in pathological populations (stance duration errors between 6-14 %, swing duration errors between 10-32 % of the actual values across populations).

Assessment of gait direction changes during straight-ahead walking in healthy elderly and Huntington disease patients using a shank worn MIMU

The aim of this study was to propose and comparatively evaluate four methods for assessing stride-by-stride changes of direction of progression, during straight walking using measurements of a magnetic and inertial unit placed above the malleolus. The four methods were evaluated by comparing their estimate of the gait changes of direction of progression with that obtained from an instrumented gait mat used as a gold standard. The methods were applied to the data obtained from the gait of both healthy subjects and patients with Huntington Disease, the latter characterized by a jerky swing phase. The results showed that the errors associated to the best estimates of the gait direction changes were about 10% of its range of variability for the healthy subjects and increased to about 30% for the patients, both walking at comfortable speed when the range of variability is the largest. Additional testing on gait at various radius of curvature should be carried out to fully validate the MIMU-based estimates.

Muscle shortening manoeuvre reduces pain and functional impairment in shoulder impingement syndrome: clinical and ultrasonographic evidence

OBJECTIVES

To evaluate the short-term efficacy of muscle shortening manoeuvre (MSM), by inducing an increase in strength of the shoulder muscles, for the treatment of shoulder impingement syndrome (SIS).

METHODS

Sixty subjects (mean age: 58.6 years) with SIS were assigned to one of 3 different treatment interventions: 1) MSM: a series of fast accelerations in the upward direction was applied to the upper limb that was also submitted to forces acting in the opposite direction (added mass); 2) traditional physiotherapeutic technique: scapulothoracic gliding; 3) simple traction: the added mass was applied to the limb without the series of fast accelerations. Pain intensity, Neer's impingement sign, range of motion and muscle strength were assessed. Ultrasound (US) examination was performed before, immediately after and 30 days after each treatment to study the width of the subacromial-subdeltoid bursa, long biceps tendon sheath and acromioclavicular joint. Impingement was evaluated by dynamic examination.

RESULTS

After treatment with MSM, pain was significantly reduced (p<0.001), Neer's impingement sign was negative, range of motion and muscle strength were increased. US examination showed that the widths of the subacromial-subdeltoid bursa (p<0.001), long biceps tendon sheath (p<0.001) and acromioclavicular joint (p<0.001) were significantly reduced; impingement was no more detected. After 30 days, improvement in clinical and US findings was maintained. In the two control groups, no significant changes were observed after treatment.

CONCLUSIONS

Clinical and US findings demonstrate that MSM, by inducing an increase in muscle strength, is effective in the short-term treatment of SIS.

Break dance significantly increases static balance in 9 years-old soccer players

Static balance in young athletes is an important ability that has a relevant influence on their present and future sport performances, as well as on the reduction in risk of injury. The present study reports data collected on three homogeneous groups of 9 years-old athletes (n=10 for each group), whose static balance was monitored every two months during an overall period of six months. At the beginning of the study, all of the children in each of the three groups were performing soccer activity with a frequency (three times a week) that was kept constant during the observation period. During the six months, group 1 maintained only the soccer activity, group 2 also performed swimming activity (twice a week) in parallel with the soccer activity, while group 3 started, at month 2, to perform soccer activity with a break dance course (twice a week). Double leg stance (with eyes open and closed) and single leg stance (on dominant and non-dominant leg) tests were performed using a force platform, and the COP area calculated for each trial. Results show a clear decrease in the "soccer+break dance" players COP area values during the six months, suggesting an improvement in their static balance. The difference was significantly greater with respect to that of soccer players and "soccer+swimming" players. This was evident in all the tests performed starting from two months after the break dance activity began.