0579 Non Intrusive and Unattended Sleep Analyzer Effectively Screens Patients Suspected of Sleep Apnea: A Comparison With Polysomnography

Introduction

Sleep Apnea Syndrome (SAS) is largely underdiagnosed due to the cost and availability of Polysomnography (PSG). We aimed at evaluating the diagnosis of SAS with the WITHINGS Sleep Apnea Detector (SAD), a non-intrusive pressure and sound sensor placed under the mattress.

Methods

118 patients (67 F, 49 years, BMI 33kg/m²) suspected of SAS had an in-laboratory PSG together with Sleep Apnea Detector. From the pressure signal, Sleep Apnea Detector derives respiratory and cardiac signals and movements. From the microphone, snoring and snorting are detected. These features are used to detect sleep periods with a Random Forest classifier and apnea and hypopnea events with a Convolutional Neural Network. The Total Sleep Time (TST) and Apnea Hypopnea Index (AHI) deduced (TSTsad, AHIsad) are compared with the PSG results scored according to AASM rules (TSTpsg, AHIpsg). AHI and TST were compared using bias and Mean Absolute Error (MAE). Sensitivity, specificity, likelihood ratios (LR) and AUROC were calculated for AHI thresholds of 15 and 30/hr.

Results

The average (SD) TSTpsg was 367 (61) minutes. Sleep Apnea Detector overestimated TST by 25 minutes, 7.0% of the average duration in the sample. The precision is acceptable, with a MAE=53 minutes. Average AHIpsg was 32.5 (30.1) and AHIsad 32.8 (29.9). The bias was 0.3 (95% CI [-2.7, 3.3]), MAE=10.3. The sensitivity (Se15) and specificity (Sp15) and their 95% confidence intervals were Se15=88.0% [79.0, 94.1] and Sp15=88.6% [73.3, 96.8]. Positive and negative LR were respectively LR+15=7.70 and LR-15=0.136. AUROC15=0.926. At the 30 threshold, Se30=86.0% [73.3, 94.2] and Sp30=91.2% [81.8, 96.7]. Positive and negative LR were LR+30=9.75 and LR-30=0.153. AUROC30=0.954.

Conclusion

Sleep Apnea Detector has excellent sensitivity and specificity, low bias and good precision. Thus it can be used as an unattended SAS screening device in patients likely to suffer from SAS.

Support

WITHINGS

Reduced fibre size, capillary supply and mitochondrial activity in constitutional thinness' skeletal muscle

AIM

Constitutional thinness (CT) is a rare condition of natural low body weight, with no psychological issues, no marker of undernutrition and a resistance to weight gain. This study evaluated the skeletal muscle phenotype of CT women by comparison with a normal BMI control group.

METHODS

Ten CT women (BMI < 17.5 kg/m² ) and 10 female controls (BMI: 18.5-25 kg/m² ) underwent metabolic and hormonal assessment along with muscle biopsies to analyse the skeletal muscular fibres pattern, capillarity, enzymes activities and transcriptomics.

RESULTS

Constitutional thinness displayed similar energy balance metabolic and hormonal profile to controls. Constitutional thinness presented with lower mean area of all the skeletal muscular fibres (-24%, P = .01) and percentage of slow-twitch type I fibres (-25%, P = .02, respectively). Significant downregulation of the mRNA expression of several mitochondrial-related genes and triglycerides metabolism was found along with low cytochrome c oxidase (COX) activity and capillary network in type I fibres. Pre- and post-mitochondrial respiratory chain enzymes levels were found similar to controls. Transcriptomics also revealed downregulation of cytoskeletal-related genes.

CONCLUSION

Diminished type I fibres, decreased mitochondrial and metabolic activity suggested by these results are discordant with normal resting metabolic rate of CT subjects. Downregulated genes related to cytoskeletal proteins and myocyte differentiation could account for CT's resistance to weight gain.

Translation and validation of the French version of the Western Ontario Shoulder Instability Index (WOSI): WOSI-Fr

INTRODUCTION

The Western Ontario Shoulder Instability Index (WOSI) is a specific self-administered questionnaire measuring the functional impact on patients with chronic glenohumeral instability. In its English version, it is valid, reliable, and sensitive to change. The objective of the present study was to provide a linguistic and cross-cultural adaptation of the original version of the WOSI to French and to assess the metrologic properties of this version in patients with chronic shoulder instability.

MATERIAL AND METHODS

The WOSI was translated and adapted both linguistically and culturally to French (WOSI-Fr) according to current guidelines. The metrologic properties of the WOSI-Fr were analyzed in the following groups - unoperated patients with chronic shoulder instability (UOG), operated patients with chronic shoulder instability (OG), patients with instability (TotG=UOG+OG), and control patients (ContG) - through analysis of the construct validity by comparing the WOSI-Fr with the Rowe, Walch-Duplay, QuickDASH, and VAS pain scores, and through analysis of reliability through the reproducibility of internal consistency.

RESULTS

The WOSI-Fr version was established and then accepted by an expert group (n=7). There was a statistically significant correlation between the WOSI and the different pain and function scores for TotG, OG, and UOG (except with the VAS pain score and the QuickDASH for UOG). Reproducibility (n=27) was good: the ICC value for the total score was 0.88 (95% CI, 0.47-0.98), varying from 0.80 to 0.94 according to the four domains of the WOSI-Fr, and from 0.70 to 0.94 for the different items separately. For TotG, Cronbach's alpha was 0.953, the SEM and the MDC were 120.2 (5.7%) and 333 (15.9%), respectively.

CONCLUSION

The French version of the WOSI (WOSI-Fr) is available, adapted linguistically and culturally, valid, and reliable. We recommend using it in following up patients with shoulder instability.

LEVEL OF EVIDENCE

Prospective, level 2.

Ground-reactive forces after hallux valgus surgery

Aims

The purpose of this study was to analyse the biomechanics of walking, through the ground reaction forces (GRF) measured, after first metatarsal osteotomy or metatarsophalangeal joint (MTP) arthrodesis.

Patients and Methods

A total of 19 patients underwent a Scarf osteotomy (50.3 years, standard deviation (sd) 12.3) and 18 underwent an arthrodesis (56.2 years, sd 6.5). Clinical and radiographical data as well as the American Orthopaedic Foot and Ankle Society (AOFAS) scores were determined. GRF were measured using an instrumented treadmill. A two-way model of analysis of variance (ANOVA) was used to determine the effects of surgery on biomechanical parameters of walking, particularly propulsion.

Results

Epidemiological, radiographical and clinical data were comparable in the two groups and better restoration of propulsive function was found after osteotomy as shown by ANOVA (two way: surgery × foot) with a surgery effect on vertical forces (p < 0.01) and a foot effect on anteroposterior impulse (p = 0.01).

Conclusion

Patients who underwent Scarf osteotomy had a gait pattern similar to that of their non-operated foot, whereas those who underwent arthrodesis of the first (metatarsophalangeal) MTP joint did not totally recover the propulsive forces of the forefoot. Take home message: The main findings of this study were that after surgical correction for hallux valgus, patients who underwent scarf osteotomy had a gait pattern similar to that of their non-operated foot in terms of forefoot propulsive forces (Fz3, Iy2), whereas those who underwent arthrodesis of the first MTP joint had not. Cite this article: Bone Joint J 2016;98-B:641–6.

Recovery of gait pattern after medial patellofemoral ligament reconstruction for objective patellar instability

Gait pattern alterations were previously reported in association with objective patellar instability (OPI). Gait pattern comparison between a series of patients having undergone medial patellofemoral ligament (MPFL) reconstruction and a sample of control subjects. Thirty patients at 6 months postoperatively after MPFL reconstruction and thirty control subjects were enrolled in the study for a clinical and biomechanical assessment including gait analysis at three selected walking rates using the GAITRite(®) system. The mean raw IKDC score was 73 (± 19), and the mean Kujala knee function was 84 (± 17.5). The study of gait did not demonstrate any significant difference between the two groups at a normal and fast walking rate. At a 10 km/h running speed, the single-support phase was significantly shortened by a mean 2.33% (p < 0.05), the swing phase by a mean 2.64% (p < 0.05) and the double-support phase by a mean 3.49% (p < 0.05) on the operated side. MPFL reconstruction reported good midterm functional and clinical results in the management of OPI. At 6 months postoperatively, the patient gait pattern was similar to that observed in healthy subjects at a normal and fast walking speed. However, our study revealed persistent gait abnormalities at a 10 km/h running speed. These gait alterations seemed to be related to the ligament reconstruction in itself due to the higher strain applied on the reconstructed MPFL during running cycle (10 km/h). Level of evidence IV.

Effects of hamstring-emphasized neuromuscular training on strength and sprinting mechanics in football players

The objective of this study was to examine the effects of a neuromuscular training program combining eccentric hamstring muscle strength, plyometrics, and free/resisted sprinting exercises on knee extensor/flexor muscle strength, sprinting performance, and horizontal mechanical properties of sprint running in football (soccer) players. Sixty footballers were randomly assigned to an experimental group (EG) or a control group (CG). Twenty-seven players completed the EG and 24 players the CG. Both groups performed regular football training while the EG performed also a neuromuscular training during a 7-week period. The EG showed a small increases in concentric quadriceps strength (ES = 0.38/0.58), a moderate to large increase in concentric (ES = 0.70/0.74) and eccentric (ES = 0.66/0.87) hamstring strength, and a small improvement in 5-m sprint performance (ES = 0.32). By contrast, the CG presented lower magnitude changes in quadriceps (ES = 0.04/0.29) and hamstring (ES = 0.27/0.34) concentric muscle strength and no changes in hamstring eccentric muscle strength (ES = -0.02/0.11). Thus, in contrast to the CG (ES = -0.27/0.14), the EG showed an almost certain increase in the hamstring/quadriceps strength functional ratio (ES = 0.32/0.75). Moreover, the CG showed small magnitude impairments in sprinting performance (ES = -0.35/-0.11). Horizontal mechanical properties of sprint running remained typically unchanged in both groups. These results indicate that a neuromuscular training program can induce positive hamstring strength and maintain sprinting performance, which might help in preventing hamstring strains in football players.

Assessment of joint position sense deficit, muscular impairment and postural disorder following hemi-Castaing ankle ligamentoplasty

INTRODUCTION

Hemi-Castaing ligamentoplasty is a treatment for chronic ankle instability, accused of weakening a powerful stabilizing muscle: the peroneus brevis.

OBJECTIVES

To assess proprioceptive and muscular impairment following hemi-Castaing and impact on postural control.

METHODOLOGY

A retrospective series of 21 patients underwent clinical (Karlsson, AOFAS) and proprioceptive assessment with isokinetic assessment (evertors and invertors) on a Con-Trex dynamometer and postural assessment on a Win-Posturo force platform, at a minimum 6 months postsurgery.

RESULTS

At a mean 18 months' follow-up, mean Karlsson score was 84 and AOFAS score 88. Ankle joint position sense error was less on the operated than on the healthy side. Evertor strength deficit with respect to the healthy side was 4.7% (ns) at 30°/s and 5.7% (ns) at 120°/s in concentric mode and 6.6% (ns) in excentric mode. After surgery, the evertor/invertor ratio was >1 (in favor of the evertors). Postural values were significantly higher for the operated ankle.

DISCUSSION-CONCLUSION

Hemi-Castaing ligamentoplasty provided excellent clinical and functional results. It did not disturb the agonist/antagonist balance of the ankle muscles, and harvesting a half peroneus brevis did not impair evertor isokinetic force. Joint position sense was not impaired; indeed, deficits with respect to the contralateral side showed improvement.

LEVEL OF EVIDENCE

Retrospective study.

Force-velocity profile: imbalance determination and effect on lower limb ballistic performance

This study sought to lend experimental support to the theoretical influence of force-velocity (F-v) mechanical profile on jumping performance independently from the effect of maximal power output (P max ). 48 high-level athletes (soccer players, sprinters, rugby players) performed maximal squat jumps with additional loads from 0 to 100% of body mass. During each jump, mean force, velocity and power output were obtained using a simple computation method based on flight time, and then used to determine individual linear F-v relationships and P max values. Actual and optimal F-v profiles were computed for each subject to quantify mechanical F-v imbalance. A multiple regression analysis showed, with a high-adjustment quality (r²=0.931, P<0.001, SEE=0.015 m), significant contributions of P max , F-v imbalance and lower limb extension range (h PO ) to explain interindividual differences in jumping performance (P<0.001) with positive regression coefficients for P max and h PO and a negative one for F-v imbalance. This experimentally supports that ballistic performance depends, in addition to P max , on the F-v profile of lower limbs. This adds support to the actual existence of an individual optimal F-v profile that maximizes jumping performance, a F-v imbalance being associated to a lower performance. These results have potential strong applications in the field of strength and conditioning.

Care pathways in physical and rehabilitation medicine (PRM): the patient after shoulder stabilization surgery

This document is part of the "Care pathways in physical and rehabilitation medicine" series developed by the French Physical and Rehabilitation Medicine Society (SOFMER) and the French Physical and Rehabilitation Medicine Federation (FEDMER). For a given patient profile, each concise document describes the patient's needs, the care objectives in physical and rehabilitation medicine, the required human and material resources, the time course and the expected outcomes. The document is intended to enable physicians, decision-makers, administrators and legal and financial specialists to rapidly understand patient needs and the available care facilities, with a view to organizing and pricing these activities appropriately. Here, patients with shoulder instability requiring surgical stabilization are classified into five care sequences and two clinical categories, each of which are treated according to the same six parameters and by taking account of personal and environmental factors (according to the WHO's International Classification of Functioning, Disability and Health) that may influence patient needs.

Care pathways in physical and rehabilitation medicine (PRM): the patient after proximal humeral fracture and shoulder hemi-arthroplasty

This document is part of the "Care Pathways in Physical and Rehabilitation Medicine" series developed by the French Physical and Rehabilitation Medicine Society (Sofmer) and the French Physical and Rehabilitation Medicine Federation (Fedmer). For a given patient profile, each concise document describes the patient's needs, the care objectives in physical and rehabilitation medicine, the required human and material resources, the time course and the expected outcomes. The document is intended to enable physicians, decision-makers, administrators and legal and financial specialists to rapidly understand patient needs and the available care facilities, with a view to organizing and pricing these activities appropriately. Here, patients with acute proximal humeral fracture requiring shoulder hemi-arthroplasty are classified into four care sequences and two clinical categories, both of which are treated according to the same six parameters and by taking account of personal and environmental factors (according to the WHO's International Classification of Functioning, Disability and Health) that may influence patient needs.

Recovery of rotators strength after Latarjet surgery

The purposes of this study were to prospectively determine changes in rotator cuff strength before and after surgical shoulder stabilization by Bristow-Latarjet procedure and to better estimate time needed for rotator cuff strength recovery. 20 patients with recurrent anterior posttraumatic shoulder dislocation underwent internal (IR) and external (ER) rotator isokinetic evaluation before and 3, 6 and 21 months after Bristow-Latarjet surgery. In a seated position with 45° of shoulder abduction in the scapular plane, both shoulders were evaluated concentrically with a Con-Trex® isokinetic dynamometer at 180°∙s (- 1), 120°∙s (- 1) and 60°∙s (- 1). 3 months post-surgery, IR and ER strength of the operated shoulder were significantly lower than before surgery (- 28 ± 20% for IR, - 17 ± 17% for ER) (P<0.05). At 6 and 21 months post-surgery, IR and ER strength were comparable to strength before surgery; strength recovery is seen at 6 months post-surgery with long-term maintenance at 21 months. Given the weakness 3 months post-surgery, return to sports (including overhead and contact sports) should be discussed, and 6 months post-surgery may be a better point for an athlete to resume practicing sports. Isokinetic rotator cuff strength evaluation appears to be relevant in helping to determine the need of continuing strength rehabilitation. Pre-surgical evaluation contributes to the relevance of later comparisons.

Injuries in Youth and National Combined Events Championships

In major track and field competitions, the most risky discipline is the combined event. Therefore, we aimed to record and analyze the incidence and characteristics of sports injuries incurred during the Youth and National Combined Events Championships. During the French Athletics Combined Events Championships in 2010, all newly occurred injuries were prospectively recorded by the local organising committee of physicians and physiotherapists working in the medical centres at the stadium, in order to determine incidence and characteristics of newly occurred injuries. In total, 51 injuries and 9 time-loss injuries were reported among 107 registered athletes, resulting in an incidence of 477 injuries and 84 time-loss injuries per 1,000 registered athletes. Approximately 72% of injuries affected lower limbs and 60% were caused by overuse. Thigh strain (17.6%) was the most common diagnosis. 14 dropouts were recorded, 8 were caused by an injury (57.1%). During the National and Youth Combined Events Championships, over one third of the registered athletes incurred an injury, with an injury incidence higher than in international elite track and field competitions. Interestingly, this higher injury risk concerned the younger population affecting immature musculoskeletal structures. In combined events, preventive interventions should mainly focus on overuse and thigh injuries.

Efficiency of flexible derotator in walking cerebral palsy children

INTRODUCTION

The flexible derotator is one of the therapeutic resources used to combat primary and secondary abnormalities in walking cerebral palsy children. It was developed to reduce abnormal femoral and tibial torsions and lessen the latter's negative functional impact.

OBJECTIVE

To determine the effect of wearing a flexible derotator on anatomic and functional parameters in walking cerebral palsy children.

METHODS

We performed a retrospective study of walking cerebral palsy children by gathering data on bone-related parameters (femoral and tibial torsion) and functional parameters (distance and speed gait, and the energy expenditure index (EEI)). Fifteen walking cerebral palsy children were treated with the flexible derotator for one year and 15 untreated walking cerebral palsy children were included as controls. The two groups were compared in terms of the various parameters' change over time between the initial examination (the last examination prior to the start of the study or prior to use of the flexible derotator) and the final examination (after one year of follow-up).

RESULTS

Right femoral anteversion and right and left external tibial torsion improved. There was a significant increase in distance and speed gait and a decrease in the EEI in walking cerebral palsy children.

CONCLUSION

Our retrospective study revealed a significant improvement in functional parameters in children with cerebral palsy, as a result of wearing the flexible derotator for at least 6 hours a day for a year. Bone parameters only improved slightly. Use of the flexible derotator could improve these children's quality of life.

Proximal row carpectomy: Is early postoperative mobilisation the right rehabilitation protocol?

PURPOSE OF THE STUDY

To determine the feasibility and interest of an early rehabilitation protocol with no initial immobilisation after proximal row carpectomy.

MATERIAL AND METHODS

Thirteen patients were included in this retrospective study. Range of motion (ROM) and wrist strength (grip strength and grasp strength) were evaluated 3 and 6 weeks after surgery on the both wrists (operated and non-operated). Postoperatively, patients had no immobilisation of the wrist, and began a rehabilitation program immediately after surgery in the department of Physical Therapy and Rehabilitation under multidisciplinary team supervision. The same surgical technique was used for all patients by the same surgeon.

RESULTS

Six weeks after PRC, there was a 25-51% deficit in passive ROM and 54-64% deficit in active ROM compared to the corresponding non-operated wrist. Six weeks after PRC, mean overall grip strength was nearly 55% and Jamar dynamometer grip strength was 51% of the contralateral side.

DISCUSSION

This study shows that immediate immobilisation following PRC is unnecessary, and that early rehabilitation is of the essence. Early rehabilitation could reduce the delay necessary to recover range of motion and strength, and probably the time to return to work.

LEVEL OF EVIDENCE

Level 4, prospective cohort study.

The relationship between muscle strength and physiological age: a cross-sectional study in boys aged from 11 to 15

OBJECTIVE

To investigate the relationships between isokinetic knee flexor and extensor muscle strength and physiological and chronological age in young soccer players.

MATERIAL AND METHODS

Seventy-nine young, healthy, male soccer players (mean+/-standard deviation age: 12.78+/-2.88, range: 11 to 15) underwent a clinical examination (age, weight, height, body mass index and Tanner puberty stage) and an evaluation of bilateral knee flexor and extensor muscle strength on an isokinetic dynamometer. Participation in the study was voluntary.

RESULTS

The peak torque increased progressively (by 50%) between the ages of 11 and 15 and most significantly between 12 to 14. The knee flexor/extensor ratios only decreased significantly between 14 and 15 years of age. Puberty stage was the most important determinant of the peak torque level (ahead of chronological age, weight and height) for all angular velocities (p<0.0001). Muscle strength increased significantly between Tanner stages 1 and 5, with the greatest increase between stages 2 and 4.

CONCLUSION

The present study showed that isokinetic muscle strength increases most between 12 and 13 years of age and between Tanner stages 2 and 3. There was strong correlation between muscle strength and physiological age.