Single leg squat performance in physically and non-physically active individuals: a cross-sectional study.

BACKGROUND: Single-leg squat (SLS) is a functional test visually rated by clinicians for assessing lower limb function as a preventive injury strategy. SLS clinical rating is a qualitative evaluation and it does not count objective outcomes as kinematics data and surface electromyography (sEMG) assessment. Based on the SLS rating, the aims of this study were (i) to determine the clinical rating agreement among six raters and (ii) to assess kinematic and sEMG predictors of good SLS performance in physically and non-physically active individuals. METHODS: Seventy-two healthy adults, divided in physically active and non-physically active groups, performed three SLSs on their dominant leg. Clinical ratings, kinematic data and sEMG were acquired. By using a validated clinical scale, six expert clinicians rated each SLS watching a video at three different time points. Intra and inter-rater agreement of clinical ratings were undertaken and a binary logistic regression analysis was used to determine kinematic and sEMG as predictors of SLS performance. RESULTS: The weighted kappa coefficient for intra-rater reliability within each rater ranged between moderate and almost perfect agreement (0.55-0.85) whereas the weighted kappa coefficient for inter-rater reliability among raters was fair (0.34, time point 0; 0.31, time point 1; 0.30, time point 2). SLS analyses of physically active compared to non-physically active group showed a statistically significant difference in knee flexion and hip flexion (p = 0.041 and p = 0.023 respectively) and no difference in clinical ratings (p = 0.081). Greater knee flexion can predict the good SLS performance taking into account the belonging group (p = 0.019). CONCLUSIONS: Physically active individuals seemed to be at less risk to perform a non-good SLS and they had greater knee and hip flexions kinematics than non-physically active individuals. Knee flexion can predict the SLS performance quality therefore a greater knee flexion might also be considered a protective element from injuries. TRIAL REGISTRATION: ClinicalTrials.gov identifier (trial has been registred retrospectively: NCT03203083. Date registration: June 21, 2017.

Does knee revision after an articulated spacer implant provide normal gait restoration?

PURPOSE: The aim of this study was to quantitatively evaluate gait parameters in patients who underwent a revision procedure after an interval articulated spacer for septic knee prosthesis. METHODS: Ten adult subjects underwent three-dimensional computerized gait analysis 12 months after second-stage knee revision procedure. Kinematic and kinetic parameters were acquired and compared with a normal reference population. Data were also compared with those collected in a previous study, in which the same cohort of patients underwent gait analysis 8-14 weeks after spacer implantation. RESULTS: Kinematic and kinetic parameters did not show any significant difference between the affected and unaffected limb. Compared to normal reference population, patients treated with revision knee prosthesis showed a reduced mean gait velocity, step frequency, stride and step length, average knee range of motion, knee power and ground reaction forces. When comparing average data with those observed after spacer implant, no difference was observed in kinematic variables, while kinetic analysis demonstrated a significant improvement in knee power. CONCLUSIONS: This study shows that 1 year after second-stage knee revision surgery, kinematic and kinetic values remain lower than those observed in a normal reference population. Only slight improvements in walking ability are shown, when analysing data in comparison with those collected after a preformed articulated knee spacer. This finding points out the long time to full functional recovery after knee revision surgery and the limited improvement of gait when compared to the one achieved at the time of spacer implant.

Stress fracture of the ulna in an elite ice dancer.

Stress fracture of the ulna is a rare overuse injury often arising from repetitive excessive forearm rotation. Here we report the first case of ulnar stress fracture in a female ice dancer. Diagnosis was made by history and physical examination, with the aid of imaging studies (plain x-ray, computed tomography, and magnetic resonance imaging), and biomechanical analysis of forearm pronation and supination. Following identification and modification of the causal technical element, the ice dancer was able to continue training and competing without cessation of activity. Treatment was with a 30-day course of capacitively coupled bone stimulation to promote fracture healing, confirmed on radiography and magnetic resonance imaging. Such injuries to ice dancers may be prevented at the planning stage of technical elements in the dance program if coaches place more attention on the potentially deleterious effects of difficult positions the lifted dancer must sustain to reward points on the technical elements score. Key pointsThe technical elements in ice dancing can overload joints and bones due to the positions held by the skaters.To project a competition program as much as possible safe regarding overuse injury prevention an accurate knowledge of physiological parameters of the ice dancer and of ISU rules is necessary.

Quantitative gait analysis in patients with Parkinson treated with deep brain stimulation: the effects of a robotic gait training.

BACKGROUND: Despite Deep Brain Stimulation (DBS) improves cardinal symptoms of Parkinson's Disease (PD), its effect on walking impairment is less evident. Robotic-assisted rehabilitation systems could serve as "add-on" physical therapy for PD patients. This systems are able to anticipate and correct the trajectory of patients' motion to improve their motor function recovery. OBJECTIVE: Aim of the present study was the quantitative assessment of the effects of a Robotic-Assisted Rehabilitation Protocol (RARP) on gait patterns by means of three-dimensional gait analysis on PD patients treated with DBS. METHODS: 9 patients with PD treated with DBS were submitted to 5 weeks robotic-assisted rehabilitation sessions. Three-dimensional gait analysis was performed before the starting session, and one day after the last session using an optoelectronic system with passive markers. RESULTS: The RARP showed significant improvements on spatio-temporal gait parameters and on the Unified Parkinson's Disease Rating Scale motor score. CONCLUSIONS: The RARP with Lokomat may have positive effects on spatio-temporal gait parameters of PD patients and it could be an adjunct therapy for patients treated with DBS. On the other hand kinematic and kinetic gait parameters did not show significant improvements, remaining almost comparable before and after the RARP.