Luc Vanden Bossche

Heterotopic ossification: a review.

Heterotopic ossification is defined as the presence of lamellar bone at locations where bone normally does not exist. The condition must be distinguished from metastatic calcifications, which mainly occur in hypercalcaemia, and dystrophic calcifications in tumours. It is a frequent complication following central nervous system disorders (brain injuries, tumours, encephalitis, spinal cord lesions), multiple injuries, hip surgery and burns. In addition to this acquired form, hereditary causes also exist, such as fibrodysplasia ossificans progressiva, progressive osseous heteroplasia and Albrights hereditary osteodystrophy. Although these conditions are extremely rare, they can provide useful information on the physiopathology of heterotopic ossification, and thus lead to novel and causal treatment modalities. Heterotopic ossification is no trivial complication. A limitation of the range of joint motion may have serious consequences for the daily functioning of people who are already severely incapacitated because of their original lesion. Increased contractures and spasticity, pressure ulcers and increasing pain further compromise the patients capabilities. Consequently, we feel that attention should be paid to the pathogenesis and particularly the prevention and treatment of this disorder.

Physical fitness of elite Belgian soccer players by player position.

Abstract Boone, J, Vaeyens, R, Steyaert, A, Vanden Bossche, L, and Bourgois, J. Physical fitness of elite Belgian soccer players by player position. J Strength Cond Res 26(8): 2051–2057, 2012—The purpose of this study was to gain an insight into the physical and physiological profile of elite Belgian soccer players with specific regard to the players position on the field. The sample consisted of 289 adult players from 6 different first division teams. The players were divided into 5 subgroups (goalkeepers, center backs, full backs, midfielders, and strikers) according to their self-reported best position on the field. The subjects performed anaerobic (10-m sprint, 5 × 10-m shuttle run [SR], squat jump [SJ], and countermovement jump [CMJ]) and aerobic (incremental running protocol) laboratory tests. The strikers had significantly shorter sprinting times (5-, 5- to 10-m time, and SR) compared with the midfielders, center backs, and goalkeepers, whereas the full backs were also significantly faster compared with the goalkeepers and the center backs. The goalkeepers and the center backs displayed higher jumping heights (total mean SJ = 40.7 ± 4.6 cm and CMJ = 43.1 ± 4.9 cm) compared with the other 3 positions, whereas the strikers also jumped higher than the full backs and the midfielders did. Regarding the aerobic performance, both full backs and the midfielders (61.2 ± 2.7 and 60.4 ± 2.8 ml·min−1·kg−1, respectively) had a higher V[Combining Dot Above]O2max compared with the strikers, center backs, and goalkeepers (56.8 ± 3.1, 55.6 ± 3.5, and 52.1 ± 5.0 ml·min−1·kg−1, respectively). From this study, it could be concluded that players in different positions have different physiological characteristics. The results of this study might provide useful insights for individualized conditional training programs for soccer players. Aside from the predominant technical and tactical skills, a physical profile that is well adjusted to the position on the field might enhance game performance.

Vastus Medialis Obliquus Atrophy: Does It Exist in Patellofemoral Pain Syndrome?

Background: Quadriceps atrophy and in particular atrophy of the vastus medialis obliquus (VMO) muscle have been frequently related with patellofemoral pain syndrome (PFPS), despite very little objective evidence. Hypothesis: Patients with PFPS exhibit atrophy of the VMO in comparison with healthy controls. Study Design: Case-control study; Level of evidence, 3. Methods: Forty-six patients with PFPS and 30 healthy control persons with similar age, gender, body mass index, and activity index distributions underwent magnetic resonance imaging (MRI) of the quadriceps. The muscle size was determined by calculating the cross-sectional area of the total quadriceps and its components. Results: The cross-sectional area (CSA) of the VMO was significantly smaller in the PFPS group than in the control group (16.67 ± 4.97 cm2 vs 18.36 ± 5.25 cm2) (P = .040). A tendency was noted for a smaller total quadriceps CSA for the PFPS patients at midthigh level (66.99 ± 15.06 cm2 vs 70.83 ± 15.30 cm2) (P = .074). Conclusion: This is the first study to examine VMO size in PFPS patients by MRI. Patients with patellofemoral problems exhibited atrophy of the VMO. Although it is not clear whether this atrophy is a result or a cause of PFPS, the results of this study do show that atrophy of the VMO is a contributing factor in PFPS. Longitudinal, prospective studies are needed to establish the cause-effect relation of VMO atrophy and PFPS.

Effect of prior exercise on VO2 slow component is not related to muscle temperature.

INTRODUCTION It has been widely reported that the VO(2) slow component is reduced in the second of two bouts of heavy exercise. It has also been shown that an increase in muscle temperature (Tm) produced by wearing hot-water-perfused pants causes a reduction in the VO(2) slow component. Therefore, the aim of this study was to investigate whether the effect of prior heavy exercise on the VO(2) slow component of subsequent heavy exercise is related to the warming-up of the exercising limbs. METHODS Six male subjects completed an exercise protocol consisting of two constant-load exercise bouts (EX-1 and EX-2) at 90% VO(2peak), separated by 6 min of rest. The Tm of the m. vastus lateralis was measured with an indwelling thermistor. Seven days later, the subjects completed a second exercise protocol consisting of a passive warming-up of the upper legs until the same Tm was reached as after EX-1, followed by a constant-load work bout (EX-3) identical to EX-1 and EX-2. RESULTS Tm reached comparable levels at the start of EX-2 and EX-3 (37.3 +/- 0.6 degrees C and 37.2 +/- 0.3 degrees C, respectively). The VO(2) slow component (measured as deltaVO(2)(6-2 min)) was reduced by 57% after prior heavy exercise ( < 0.05), whereas no significant reduction was observed after prior passive warming-up. CONCLUSIONS The results of this study indicate that the reduction in VO(2) slow component observed after prior heavy exercise cannot be explained by an increase in muscle temperature of the upper legs.

Free radical scavengers versus methylprednisolone in the prevention of experimentally induced heterotopic ossification

The etiology of heterotopic ossification (HO) is still obscure, it is difficult to devise an effective preventive or therapeutic approach. The options for the prevention of HO are still limited. The prophylactic effect of nonsteroidal anti‐inflammatory drugs (NSAIDs) is insufficient. Moreover, NSAIDs increase the risk of nonunion and loosening in patients with multiple joint injuries. The present experimental study was designed to compare methylprednisolone with free radical scavengers for the prevention of HO. The model of Michelsson et al. was used to induce HO in the hind legs of 30 female New Zealand albino rabbits, weighing approx. 4 kg. The animals were randomized into three groups of 10 animals each, and received daily either placebo, a free radical scavenger cocktail [allopurinol and N‐acetylcysteine (A/A)], or methylprednisolone in a randomized, double‐blind fashion. Every four days, X‐rays were obtained to measure the thickness and the length of new bone formation at the thigh. A statistically significant difference in thickness and length of newly formed bone was found between the three groups. In the placebo group HO increased from day 16 toward a medium length of 6 mm and a median thickness of 1.5 mm. In the A/A group, no signs of HO were found. In the methylprednisolone group, only one animal presented minor HO from day 32. Both free radical scavengers and methylprednisolone were found to inhibit HO, and may be considered effective measures for the prevention of heterotopic bone formation. However, it could not be demonstrated which of the two had the strongest inhibitory effect.

Vibration perception threshold in relation to postural control and fall risk assessment in elderly

Abstract Purpose: This study investigates (i) the potential discriminative role of a clinical measure of peripheral neuropathy (PN) in assessing postural performance and fall risk and (ii) whether the integration of a simple screening vibration perception threshold (VPT) for PN in any physical (fall risk) assessment among elderly should be recommended, even if they do not suffer from DM. Method: One hundred and ninety-five elderly were entered in a four-group model: DM with PN (D+; n = 75), DM without PN (D−; n = 28), non-diabetic elderly with idiopathic PN (C+; n = 31) and non-diabetic elderly without PN (C−; n = 61). Posturographic sway parameters were captured during different static balance conditions (AMTI AccuGait, Watertown, MA). VPT, fall data, Mini-Mental State Examination and Clock Drawing Test were registered. Two-factor repeated-measures ANOVA was used to compare between groups and across balance conditions. Results: The groups with PN demonstrated a strikingly comparable, though bigger sway, and a higher prospective fall incidence than their peers without PN. Conclusions: The indication of PN, irrespective of its cause, interferes with postural control and fall incidence. The integration of a simple screening for PN (like bio-thesiometry) in any fall risk assessment among elderly is highly recommended. Implications for Rehabilitation The indication of peripheral neuropathy (PN), irrespective of its cause, interferes with postural control and fall incidence. Therefore, the integration of a simple screening for PN (like bio-thesiometry) in any fall risk assessment among elderly is highly recommended. It might be useful to integrate somatosensory stimulation in rehabilitation programs designed for fall prevention.

Is core stability a risk factor for lower extremity injuries in an athletic population? A systematic review

OBJECTIVES To research and summarize the literature regarding the role of core stability as a risk factor in the development of lower extremity injuries in an athletic population. METHODS Pubmed, Web of Science and Embase were searched in August 2016 to systematically review studies, which related core muscle functioning and core stability to lower extremity injuries. RESULTS Nine articles were included in the systematic review. Various components of core stability were found to be related to lower extremity musculoskeletal injuries in healthy athletic populations. Core strength, core proprioception and neuromuscular control of the core were found to be a risk factor in the development of lower extremity injuries. However, conflicting evidence was found for core endurance as a risk factor for lower extremity injuries. CONCLUSION This systematic review provides preliminary evidence for the association between impaired core stability and the development of lower extremity injuries in healthy athletes. Deficits in various aspects of core stability were identified as potential risk factors for lower extremity injuries. As such, core stability needs to be considered when screening athletes.

Chronic fatigue syndrome - an update.

Background: Chronic fatigue syndrome is a widespread condition with a huge impact not only on a patient’s life, but also on society as evidenced by substantial losses of productivity, informal costs, and medical expenses. The high prevalence rates (0.2–6.4%) and the low employment rates (27–41%) are responsible for the enormous burden imposed on society, with loss of productivity representing the highest cost. The objective of this review is to systematically review the recent literature on chronic fatigue syndrome/myalgic encephalomyelitis. Methods: The published literature between 1 January 1990 and 1 April 2015 was searched using the MEDLINE, Cochrane Library, and Web of Sciences databases. The reference lists of the selected articles were screened for other relevant articles. Results and conclusions: Despite extensive research, none of the proposed etiological factors have shown strong, reproducible scientific evidence. Over the years, the biopsychosocial model integrating many of the proposed hypotheses has been gaining popularity over the biomedical model, where the focus is on one physical cause. Since the etiological mechanism underlying chronic fatigue syndrome is currently unknown, disease-specific treatments do not exist. Various treatments have been investigated but only cognitive behavior therapy (CBT) and graded exercise therapy (GET) have shown moderate effectiveness.

Effect of whole body vibration on intracompartmental pressure in the lower leg

BackgroundWhole body vibration has important effects on neuromuscular functions. It seems to be a promising tool in the conservative treatment and rehabilitation of compartment syndrome. In the present study we investigated the effect of whole body vibration on intracompartmental pressure in the lower leg during a strenuous static exercise program.MethodsWe conducted a cross-over pilot study in which fifteen healthy male subjects participated. They twice performed a 20.5-min static exercise program on the Fitvibe Medical whole body vibration device, once with 27 Hz vibrations and once without. The intracompartmental pressure was measured by two examiners at the superficial posterior compartment of the left and right lower leg, at rest and during the exercise programs.ResultsA general linear model for repeated measures showed a significant difference between the exercise program with vibrations and that without (P = 0.001) and a significant difference in intracompartmental pressure for the factor time of measurement (P < 0.001). Mean intracompartmental pressure was at any point in time lower in the vibrating than in the non-vibrating exercise conditions, though not always significant. In the program with vibrations the exercise pressures showed a non-significant trend to decrease (from 23.5 mmHg to 21.3 mmHg) as the program advanced, while in the non-vibration program, there was a trend to increase (from 24.1 to 27.9 mmHg).ConclusionsThe mean intracompartmental pressure was lower when whole body vibration at 27 Hz was superimposed. Therefore, whole body vibration seems to be a possible tool to lower intracompartmental pressure. Further research is needed to confirm whether these findings are also applicable in patients, athletes, and in dynamic exercises.

Evaluating abdominal core muscle fatigue: Assessment of the validity and reliability of the prone bridging test

The aims of this study were to research the amplitude and median frequency characteristics of selected abdominal, back, and hip muscles of healthy subjects during a prone bridging endurance test, based on surface electromyography (sEMG), (a) to determine if the prone bridging test is a valid field test to measure abdominal muscle fatigue, and (b) to evaluate if the current method of administrating the prone bridging test is reliable. Thirty healthy subjects participated in this experiment. The sEMG activity of seven abdominal, back, and hip muscles was bilaterally measured. Normalized median frequencies were computed from the EMG power spectra. The prone bridging tests were repeated on separate days to evaluate inter and intratester reliability. Significant differences in normalized median frequency slope (NMFslope) values between several abdominal, back, and hip muscles could be demonstrated. Moderate‐to‐high correlation coefficients were shown between NMFslope values and endurance time. Multiple backward linear regression revealed that the test endurance time could only be significantly predicted by the NMFslope of the rectus abdominis. Statistical analysis showed excellent reliability (ICC=0.87‐0.89). The findings of this study support the validity and reliability of the prone bridging test for evaluating abdominal muscle fatigue.