[Sports-related concussions in youths]. / Commotions cérébrales chez le jeune sportif.

Mild head trauma can be associated with concussion, defined as transient brain function impairment without radiological findings. Sports-related concussion is also reported in pediatrics (rugby, ice hockey, football, boxing, etc.). Misdiagnosis can lead to persistent neurocognitive signs with athletic and academic problems. Consensual tools are available, but they are not well-known by first-line doctors, coaches, and patients or parents. Concussed players should not be allowed to return to the field on the same day. Return to play should be gradual over 3weeks or more. School activities may need to be modified to favor cognitive rest. Prevention is based on risk information and knowledge transfer, rule changes, and protective helmets, whose effectiveness is not always proven.

[Postexercise duplex ultrasound to diagnose external iliac endofibrosis]. / Endofibrose de l'artère iliaque externe diagnostiquée par écho-doppler post-effort.

Arterial endofibrosis is a disease of recent discovery which concerns high-performance athletes, predominantly competitive cyclists. The preferential location is the external iliac artery. The symptoms are diverse (pain, edema, paresthesia), always linked to an effort. The diagnosis may be delayed due to atypical symptoms in athletes. Complementary tests are measure of the systolic pressure index after exercise, duplex ultrasound, CT angiography, MR angiography and arteriography. We report a case of endofibrosis where late diagnosis was established with postexercise duplex ultrasound, while CT angiography and arteriography failed to reveal characteristic abnormalities.

Peroneus quartus and functional ankle instability.

INTRODUCTION: Physical and rehabilitation medicine physicians commonly see patients with chronic functional ankle instability. The main anatomical structures involved in ankle stability are the peroneus (fibularis) brevis and peroneus longus muscles. Several anatomical muscle-tendon variations have been described in the literature as being sometimes responsible for this instability, the peroneus quartus muscle being the most frequent. The objective of this clinical study is to discuss the implication of the bilateral peroneus quartus muscle in functional ankle instability. CLINICAL CASE: This 26-year-old patient was seen in PM&R consultation for recurrent episodes of lateral ankle sprains. The clinical examination found a moderate hyperlaxity on the right side in bilateral ankle varus. We also noted a bilateral weakness of the peroneus muscles. Additional imaging examinations showed a supernumerary bilateral peroneus quartus. The electroneuromyogram of the peroneus muscles was normal. DISCUSSION: In the literature the incidence of a supernumerary peroneus quartus muscle varies from 0 to 21.7%. Most times this muscle is asymptomatic and is only fortuitously discovered. However some cases of chronic ankle pain or instability have been reported in the literature. It seems relevant to discuss, around the clinical case of this patient, the impact of this muscle on ankle instability especially when faced with lingering weakness of the peroneus brevis and longus muscles in spite of eccentric strength training and in the absence of any neurological impairment. One of the hypotheses, previously described in the literature, would be the overcrowding effect resulting in a true conflict by reducing the available space for the peroneal muscles in the peroneal sheath.

Effect of a plaster containing DHEP and heparin in acute ankle sprains with oedema: a randomized, double-blind, placebo-controlled, clinical study.

OBJECTIVE: Ankle sprains are the most frequent injuries in sport and daily life, and are usually treated with anti-inflammatory drugs or compounds that have an effect on microcirculation. The efficacy and tolerability of a novel plaster containing both diclofenac epolamine (DHEP) and heparin in the treatment of acute painful ankle sprains with oedema was investigated in a randomized, double-blind, placebo-controlled study. RESEARCH DESIGN AND METHODS: This study, carried out in 32 French medical centres, enrolled 233 patients (148 male and 86 female, aged 18-65 years) with an ankle sprain that had occurred within the previous 48 hours. Patients were treated once daily with DHEP heparin or placebo plaster for 7 days. MAIN OUTCOME MEASURES: Reduction in ankle joint swelling measured by submalleolar circumference was the primary efficacy endpoint; secondary endpoints were pain (at rest, in active mobilization, by passive stretch and by pressure), functional disability and global judgement of efficacy and tolerability. RESULTS: DHEP heparin-treated patients experienced a significantly greater reduction in joint swelling compared with placebo (p = 0.005). The reduction in pain was also in favour of DHEP heparin patients, with significantly lower pain in DHEP heparin-treated than placebo-treated patients within 3 hours of the first application (p < 0.05). Only two patients in the DHEP heparin plaster group and six in the placebo group experienced minor adverse events, all of which resolved spontaneously. By design, the study was limited to a placebo-controlled comparison, and there was no test for possible selection bias (subsequently ruled out by choice of efficacy parameters and measures) that may have resulted in a baseline imbalance between patient groups. CONCLUSIONS: Results confirm the efficacy of DHEP heparin plaster compared with placebo for the treatment of painful ankle sprain with oedema. Prompt control of pain and oedema may shorten the time to initiation of a rehabilitation programme, thus reducing the risk of ankle disability recurrence and the development of chronic injury.

Eccentric reinforcement of the ankle evertor muscles after lateral ankle sprain.

To compare two methods of ankle evertor muscle reinforcement after ankle sprain: concentric vs eccentric reinforcement. Eighteen subjects practising sport with first episode of ankle sprain. The first randomized group underwent conventional physical therapy including concentric reinforcement of the evertor ankle muscles [concentric group (CG)]. The second randomized group underwent eccentric reinforcement [eccentric group (EG)]. At the end of the physical therapy, the strength of the evertor muscles was tested using an isokinetic dynamometer. The measurements were peak torques in the concentric and eccentric modes; ankle strength deficits, expressed as percentages of the healthy ankle values recorded in the concentric and eccentric modes; ratios between concentric/eccentric values. After the concentric reinforcement, in the CG group, there is both significant concentric strength deficit and an eccentric strength deficit on the injured side in comparison with the healthy side. After the eccentric reinforcement in the EG group, the muscle strength was significantly greater during concentric movements. Eccentric rehabilitation therefore restored the strength of the injured evertor muscles. These results show the value of this method, especially as the weakness of these muscles after sprains is one of the main risk factors contributing to instability and the recurrence of sprains.

Comparative study of clinical and ultrasonographic evaluation of lateral collateral ligament sprains of the ankle.

AIM: Clinical examination is sometimes insufficient to assess the severity of lateral collateral ligament (LCL) sprain of the ankle, making it difficult to choose the most appropriate treatment. The aim of this study was to compare the assessment of clinical signs and the ultrasonographic findings in recent LCL sprain of the ankle. METHODS: This was a retrospective cross-sectional study. Spearman's rank correlation test and multiple regression analysis were used to assess correlations between clinical signs and type of ligament injury. Fisher's linear discriminant analysis was used to determine most contributive signs in ligament tear diagnosis. RESULTS: No single clinical sign was correlated with the severity of ligament injury as revealed by ultrasonography in the 34 patients analyzed. Careful assessment of all the usual clinical signs of severity seems to better guide the diagnosis of the presence or absence of ligament tearing. CONCLUSIONS: These results confirm the lack of correlation between clinical examination and the anatomic injury in distension or partial tearing of the anterior talofibular ligament. They raise questions about the usefulness of clinical classifications and suggest a broadening of the indications for ultrasonographic exam in ambiguous situations, particularly for athletes showing few signs of severe injury, in order to ensure optimal treatment and a faster recovery.

[Isokinetic dynamometer measurement of shoulder rotational strength in healthy elite athletes (swimming, volley-ball, tennis): comparison between dominant and nondominant shoulder]. / Mesure de la force des muscles rotateurs de l'épaule chez des sportifs sains de haut niveau (natation, volley-ball, tennis) par dynamomètre isocinétique: comparaison entre épaule dominante et non dominante.

OBJECTIVE: To compare lateral rotator (LR) and medial rotator (MR) muscle strength of both shoulders in a sport involving asymmetrical movements (tennis), symmetrical movements (swimming), and symmetrical and asymmetrical movements (volley-ball). MATERIALS AND METHODS: Retrospective study of 42 healthy elite athletes (18 women: 14 tennis players, 19 swimmers and 9 volleyball players. We evaluated the strength of LR and MR of both shoulders by Cybex Norm isokinetic dynamometer, in the concentric mode, in the modified Davies position, at 2 different speeds (60 degrees and 180 degrees s(-1)) and analysed peak torque of LR and MR and LR/MR ratios. RESULTS: TENNIS: The MR peak torque of the dominant shoulder was significantly higher than that of the non-dominant shoulder. The LR/MR ratio of the dominant shoulder was significantly lower than the non dominant shoulder in women. SWIMMING: The LR strength and LR/MR ratio of the dominant shoulder was higher than the non dominant side in men at 60 degrees/second. Both shoulders showed comparable strength in women. VOLLEYBALL: Shoulder muscular strength was symmetrical. CONCLUSION: The higher strength of MR muscles in the dominant shoulder of tennis players (asymmetrical movements) has been reported in the literature. Athletes show asymmetrical shoulder strength in swimming, a symmetrical sport and similar LR and MR strength in both shoulders in volleyball, a sport with asymmetrical movements. To our knowledge, these results have never been reported before.

[Posture and movement analysis and sports medicine]. / Analyse de la posture et du mouvement et médecine du sport.

The use of posture and movement analysis methods has developed during the past 15 years. These methods are of special interest in the field of sport sciences and have allowed to improve the understanding of physiology of posture and movement in athletes. More recently these methods have been used in the field of sport medicine. In some cases, they have helped to identify abnormalities which cannot be seen on standard clinical examination and to understand the mechanism of lesions occurring during sport activities. For the future these methods should provide useful information for understanding the physiopathology of lesions, for developing prevention of pathologies related to sport and for elaborating and assessing new treatment protocols in the field of sport medicine.

[Delayed post effort muscle soreness]. / Douleurs musculaires posteffort.

Muscle intolerance to exercise may result from different processes. Diagnosis involves confirming first the source of pain, then potential pathological myalgia. Delayed-onset muscle soreness (DOMS), commonly referred as tiredness, occurs frequently in sport. DOMS usually develops 12-48 h after intensive and/or unusual eccentric muscle action. Symptoms usually involve the quadriceps muscle group but may also affect the hamstring and triceps surae groups. The muscles are sensitive to palpation, contraction and passive stretch. Acidosis, muscle spasm and microlesions in both connective and muscle tissues may explain the symptoms. However, inflammation appears to be the most common explanation. Interestingly, there is strong evidence that the progression of the exercise-induced muscle injury proceeds no further in the absence of inflammation. Even though unpleasant, DOMS should not be considered as an indicator of muscle damage but, rather, a sign of the regenerative process, which is well known to contribute to the increased muscle mass. DOMS can be associated with decreased proprioception and range of motion, as well as maximal force and activation. DOMS disappears 2-10 days before complete functional recovery. This painless period is ripe for additional joint injuries. Similarly, if some treatments are well known to attenuate DOMS, none has been demonstrated to accelerate either structural or functional recovery. In terms of the role of the inflammatory process, these treatments might even delay overall recovery.

Combined effect of heat stress, dehydration and exercise on neuromuscular function in humans.

This study examined the combined effect of exercise induced hyperthermia and dehydration on neuromuscular function in human subjects. Six trained male runners ran for 40 min on a treadmill at 65% of their maximal aerobic velocity while wearing a tracksuit covered with an impermeable jacket and pants to impair the evaporation of sweat. These stressful experimental running conditions led the runners to a physiological status close to exhaustion. On average, the 40 min run ended at a heart rate of 196 (SD 8) beats.min-1, a tympanic temperature of 40 (SD 0.3) degrees C and with a loss of body mass of 2 (SD 0.5)%. Pre- and post-running strength tests included measurements of maximal knee extension and flexion torques in both isometric and isokinetic (at 60 and 240 degrees.s-1) conditions. A 20 s endurance test at 240 degrees.s-1 was also performed. Surface electromyographic (EMG) activity was recorded from six knee extensor and flexor muscles during the entire protocol. The treadmill run led to clear decrements in maximal extension torque and EMG activity both in isometric and at the slowest isokinetic velocity (60 degrees.s-1). However, no differences in these parameters were observed at 240 degrees.s-1. Furthermore, the EMG patterns of the major knee extensor and flexor muscles remained remarkably stable during the treadmill run. These results demonstrate that the exercise-induced hyperthermia and dehydration in the present experiments had only minor effects on the neuromuscular performance. However, it is also suggested that high internal body temperature per se could limit the production of high force levels.