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.

Effect of a Home-based Balance Training Protocol on Dynamic Postural Control in Subjects with Chronic Ankle Instability.

The aim of this study was to establish the presence of postural deficits in subjects with chronic ankle instability (CAI) and to assess the effect of an 8-week balance training program on dynamic postural control. A total of 43 subjects with CAI and 31 controls participated in this case-control study. Participants with CAI performed an 8-week home-based balance training, including 3 sessions a week. As main outcome measure, postural control was quantified after a vertical drop by means of the dynamic postural stability index (DPSI). Perceptual outcomes were documented using the FADI, FADI-Sport and VAS scales. At baseline, subjects with CAI displayed higher anterior/posterior and vertical postural instability, a poorer DPSI, and lower subjective stability scores compared to the control group. After balance training, all subjective stability scores improved significantly, although no changes were noted for the stability indices. In conclusion, subjects with CAI have an impaired postural control. As a treatment modality, balance training exhibits the capability of improving the subjective feeling of instability in subjects with CAI. However, there was no effect on dynamic postural control. Further research on the explanatory mechanisms of balance training is warranted, and other training modalities should be considered.

Review of clinical approaches and diagnostic quantities used in pedobarographic measurements.

The non-invasive nature of pedobarographic measurements is particularly attractive to researchers for analyzing and characterizing the impact of specific pathological foot conditions. However, adequate clinical use of pedobarographic technology requires a profound technical and methodological knowledge. Several papers summarized the technical capacities of pedobarographic technology. Moreover, methodological expertise has grown considerably during the last two decades. Therefore, two crucial decisions have to be made before pathomechanical modelling or functional interpretation of foot and lower limb disorders can be pursued. The first is the selection of the specific method to analyse the dynamic plantar footprint, and the second is the choice of parameters to quantify the results. In the first part of this paper, we review the different methods used to analyse the dynamic plantar footprint and discuss their conceptual backgrounds. We also aim to illustrate the clinical relevance of each method and elaborate on the future perspectives. In the second part, we review quantification methods of pedobarographic measurements. The latter is of primary relevance to clinicians and investigators with a special interest in foot and lower limb biomechanics.

Effect of tape on dynamic postural stability in subjects with chronic ankle instability.

The objective of our study was to evaluate the effect of taping on the dynamic postural stability during a jump landing protocol in subjects with chronic ankle instability (CAI). For this purpose, 28 subjects with CAI performed a sagittal and frontal plane landing task in a non-taped and taped condition. As main outcome measure, the dynamic postural stability index (DPSI) was calculated. In addition, subjective feelings of instability and perceived difficulty level were assessed. Furthermore, mechanical effectiveness of the tape on the ankle joint was determined by registering 3D kinematics. 3 subjects were excluded based on discomfort during the landing protocol. Study results indicated that the tape reduced plantar flexion and inversion at the ankle at touchdown and range of motion in the landing phase. There was, however, no effect on the DPSI or on its directional subcomponents. Subjective feelings of stability with tape improved significantly, whereas perceived difficulty did not change. In conclusion, our taping procedure did not improve postural control during a sagittal and frontal plane landing task in subjects with CAI. Perceived instability did improve and is considered an important treatment outcome, which suggests that taping could be considered as a treatment modality by clinicians.

Comparison of foot segmental mobility and coupling during gait between patients with diabetes mellitus with and without neuropathy and adults without diabetes.

BACKGROUND: Reduction in foot mobility has been identified as a key factor of altered foot biomechanics in individuals with diabetes mellitus. This study aimed at comparing in vivo segmental foot kinematics and coupling in patients with diabetes with and without neuropathy to control adults. METHODS: Foot mobility of 13 diabetic patients with neuropathy, 13 diabetic patients without neuropathy and 13 non-diabetic persons was measured using an integrated measurement set-up including a plantar pressure platform and 3D motion analysis system. In this age-, sex- and walking speed matched comparative study; differences in range of motion quantified with the Rizzoli multisegment foot model throughout different phases of the gait cycle were analysed using one-way repeated measures analysis of variance (ANOVA). Coupling was assessed with cross-correlation techniques. FINDINGS: Both cohorts with diabetes showed significantly lower motion values as compared to the control group. Transverse and sagittal plane motion was predominantly affected with often lower range of motion values found in the group with neuropathy compared to the diabetes group without neuropathy. Most significant changes were observed during propulsion (both diabetic groups) and swing phase (predominantly diabetic neuropathic group). A trend of lower cross-correlations between segments was observed in the cohorts with diabetes. INTERPRETATION: Our findings suggest an alteration in segmental kinematics and coupling during walking in diabetic patients with and without neuropathy. Future studies should integrate other biomechanical measurements as it is believed to provide additional insight into neural and mechanical deficits associated to the foot in diabetes.

Effects of in vivo exercise on ankle cartilage deformation and recovery in healthy volunteers: an experimental study.

OBJECTIVE: To monitor ankle cartilage 3D volume changes after in vivo exercise and during recovery. METHOD: Based on 3D MRI, 3D volumes of talar and tibial cartilage were calculated before and after 30 bilateral knee bends in 12 healthy volunteers. 3D volumes were calculated at five time points (one pre- and four post-scans) determining deformation and recovery for both cartilage plates of interest. Post-scans ran immediately after the exercise and were repeated according to a 15 min interval. 3D volumes were subjected to repeated measures GLM. Additionally, relative surface area use during deformation was compared between plates using a Wilcoxon Signed Ranks test and its correlation with deformation was investigated using Spearman's rho. RESULTS: Mean 3D volume change percentages for talar cartilage after the exercise were: -10.41%, -8.18%, -5.61% and -3.90%. For tibial cartilage mean changes were: -5.97%, -5.75%, +0.89% and +1.51%. For talar cartilage changes were significant, except following 30 min post-exercise. For tibial cartilage no changes were significant. At all time points, no significant differences in relative volume changes between both cartilage plates existed. Although no significant differences in relative surface area use between plates were revealed, a moderate to strong correlation with deformation existed. CONCLUSION: Ankle cartilage endures substantial deformation after in vivo loading that was restored within 30 min for the talus. Overall cartilage contact area involvement might be associated with cartilage quality maintenance in the upper ankle. Talar cartilage is suggested to play a critical role in intra-articular shock attenuation when compared to tibial cartilage.

Functional adaptation of knee cartilage in asymptomatic female novice runners compared to sedentary controls. A longitudinal analysis using delayed Gadolinium Enhanced Magnetic Resonance Imaging of Cartilage (dGEMRIC).

OBJECTIVE: To longitudinally estimate the change in glycosaminoglycan content of knee cartilage in asymptomatic untrained female novice runners participating in a Start To Run program (STR) compared to sedentary controls. METHOD: Nine females enrolling in a 10-week STR and 10 sedentary controls participated voluntarily. Prior to and after the 10-week period, both groups were subjected to dGEMRIC imaging. dGEMRIC indices of knee cartilage were determined at baseline and for the change after the 10-week period in both groups. Based on a self-reported weekly log, physical activity change during the study was depicted as decreased, unchanged or increased. The Mann-Whitney U and Kruskal-Wallis tests were applied to test the hypotheses that dGEMRIC changes occurred between groups and according to physical activity changes respectively. RESULTS: No significant differences were established between groups for dGEMRIC indices at baseline (P=0.541). A significant positive change of the median dGEMRIC index in the runners group was demonstrated when compared to the controls [+11.66ms (95% CI: -25.29, 44.43) vs -9.56ms (95% CI: -29.55, 5.83), P=0.006]. The change in dGEMRIC index differed significantly according to physical activity change (P=0.014), showing an increase in dGEMRIC index with increasing physical activity. CONCLUSION: Since cartilage appears to positively respond to moderate running when compared to a sedentary lifestyle, this running scheme might be considered a valuable tool in osteoarthritis prevention strategies. Caution is warranted when applying these results to a wider population and to longer training periods.

A prospective study on gait-related intrinsic risk factors for lower leg overuse injuries.

OBJECTIVE: To determine prospectively gait-related risk factors for lower leg overuse injury (LLOI). DESIGN: A prospective cohort study. SETTING: Male and female recruits from a start-to-run (STR) programme during a 10-week training period. PARTICIPANTS: 131 healthy subjects (20 men and 111 women), without a history of any lower leg complaint, participated in the study. INTERVENTIONS: Before the start of the 10-week STR programme, plantar force measurements during running were performed. During STR, lower leg injuries were diagnosed and registered by a sports physician. MAIN OUTCOME MEASURES: Plantar force measurements during running were performed using a footscan pressure plate. RESULTS: During the STR, 27 subjects (five men and 22 women) developed a LLOI. Logistic regression analysis revealed that subjects who developed a LLOI had a significantly more laterally directed force distribution at first metatarsal contact and forefoot flat, a more laterally directed force displacement in the forefoot contact phase, foot flat phase and at heel-off. These subjects also had a delayed change of the centre of force (COF) at forefoot flat, a higher force and loading underneath the lateral border of the foot, and a significantly higher directed force displacement of the COF at forefoot flat. CONCLUSIONS: These findings suggest that a less pronated heel strike and a more laterally directed roll-off can be considered as risk factors for LLOI. Clinically, the results of this study can be considered important in identifying individuals at risk of LLOI.

Effective prevention of sports injuries: a model integrating efficacy, efficiency, compliance and risk-taking behaviour.

In 1992 van Mechelen et al published a "sequence of prevention model" based on a four-step process. This model has been widely used to implement preventive measures in response to sports injuries. However, the execution of this model has been shown to lack validity in determining the success of a preventive measure. A modified model has therefore been proposed which incorporates additional steps that enable the inclusion of external factors with a significant effect on the outcome of a prevention intervention. This expansion of van Mechelen's model leads to a more global model in which the compliance level and risk-taking behaviour of the individual and the assessment of efficiency of the stakeholders have a key influence on the preventive measure. This model gives a better insight into the different processes in injury prevention that can be used by clinicians, coaches and managers to decide whether to implement a preventive measure programme.

Gait-related intrinsic risk factors for patellofemoral pain in novice recreational runners.

OBJECTIVE: To determine prospectively gait-related intrinsic risk factors for patellofemoral pain (PFP) in a population of novice recreational runners. DESIGN: Prospective cohort study. PARTICIPANTS: 102 novice recreational runners (89 women) with no history of knee or lower leg complaints. INTERVENTIONS: The standing foot posture of the subjects was examined and plantar pressure measurements during running were collected. The subjects then participated in a 10-week "start to run" programme. During this period all sports injuries were registered by a sports medicine physician. MAIN OUTCOME MEASUREMENTS: The relationship between the standing foot posture and PFP was investigated and gait-related intrinsic risk factors for PFP were determined. RESULTS: The 17 runners who developed PFP exerted a significantly higher vertical peak force underneath the lateral heel and metatarsals 2 and 3. Logistic regression analysis showed that a significantly higher vertical peak force underneath the second metatarsal and shorter time to the vertical peak force underneath the lateral heel were predictors for PFP. No significant evidence was found for an association between an excessively pronated or supinated foot posture and the development of PFP. CONCLUSIONS: The findings suggest that an excessive impact shock during heel strike and at the propulsion phase of running may contribute to an increased risk of developing PFP. The hypothesis that persons at risk for PFP show an altered static foot posture in comparison with non-afflicted persons is not supported by the results of this study.

The role of stretching in tendon injuries.

The function of tendons can be classified into two categories: tensile force transmission, and storage and release of elastic energy during locomotion. The action of tendons in storing and releasing energy is mainly seen in sports activities with stretch-shortening cycles (SSCs). The more intense the SSC movements are (jumping-like activities), the more frequently tendon problems are observed. High SSC movements impose high loads on tendons. Consequently, tendons that frequently deal with high SSC motion require a high energy-absorbing capacity to store and release this large amount of elastic energy. As the elasticity of tendon structures is a leading factor in the amount of stored energy, prevention and rehabilitation programmes for tendon injuries should focus on increasing this tendon elasticity in athletes performing high SSC movements. Recently, it has been shown that ballistic stretching can significantly increase tendon elasticity. These findings have important clinical implications for treatment and prevention of tendon injuries.

Electrodynographic evaluation of the foot during treadmill versus overground locomotion.

Biomechanical foot function as expressed by the duration of successive ground contact phases and by dynamic variables, such as the peak pressure on different parts of the foot, their respective loading rate, and duration, is compared for two walking and running conditions: overground on a 20-m walkway and on a treadmill. Statistical analysis revealed foot pressure characteristics as measured with a Electrodynogram during walking and running to alter significantly when using a treadmill. The differences were more pronounced for walking than for running. During walking, loading of the forefoot tends to last longer (longer propulsion phase) on a treadmill. Loading rate is decreased for the whole foot during either walking or running. Maximum heel pressure is diminished for walking but increased during running on a treadmill. Moderate variations of treadmill velocity were shown to have no significant influence on the measurements.

Monostotic localization of Paget disease in the hand.

Paget disease rarely affects the hand and when it does, there is usually a polyosteotic involvement. Only a few cases have been described in the literature on monostotic localization in the hand. This paper adds two cases with solitary involvement of a metacarpal.

The Sauvé-Kapandji procedure for nonrheumatic disorders of the distal radioulnar joint.

The Sauvé-Kapandji procedure has received little attention until recently. Follow-up survey was performed of 31 wrists with nonrheumatic disorders. The wrists were evaluated with the Cooney score. A satisfactory result with good pain relief was obtained in 87% of the patients. The most frequent complication, reossification of the gap that is created, can be avoided with correct operative technique.

[Correction of severe deformities of the foot, using Ilizarov's equipment]. / Correction des déformations sévères du pied par l'appareil d'Ilizarov.

MATERIAL AND METHODS: 38 feet in 36 patients who underwent a progressive foot correction without osteotomies, with an Ilizarov frame have been reviewed. There were 23 equinovarus, 2 equinovalgus, 13 equinus deformities. In 20 patients, the deformity had relapsed after one to four previous operations. The mean follow-up was 22 (12-35) months. The mean age was 17 years (6-68). There were 15 females and 21 males. RESULTS: All but 4 patients were satisfied with the result, although 15 still had pain during daily activities. The shape of the feet was distinctly improved in all patients, although residual equinus was found in 6 patients, residual varus in 2 and forefoot problems in 6. Pintract infections were encountered in half of the patients, all settled with local treatment, adjustement of the tension of the wires and antibiotics. Three specific complications were encountered: talus subluxations (7), toe contractures (6), relapse of equinus (4). DISCUSSION: Few alternatives are available to correct severe foot deformities. Soft tissue releases and/or wedge osteotomies are technically demanding, cause shortening of the foot, correct only one predominant component, are contraindicated in patients with infections or a poor vascular or skin condition. Progressive correction by the Ilizarov method is a valuable alternative, although we would like to stress the importance of some details in order to avoid the specific complications. Progressive correction of foot deformities by the Ilizarov frame is demanding for patient and surgeon. It should be reserved for the indications mentioned earlier and also for foot deformities combined with shortening or axial deviations.

Carpo-tarsal osteolysis. Case report and review of the literature.

A hereditary form of multicentric osteolysis is described in an 11-year-old girl whose father is also affected. The results after corrective surgery on the foot with the Ilizarov fixator and the findings during arthroscopy of the knee are discussed. The literature is reviewed.

The dynamic axial fixator in fractures of the tibia and femur. A retrospective study in 98 patients.

In a retrospective study involving 98 patients the results achieved with the dynamic axial fixator (Orthofix) in closed or open fractures of the tibia or femur treated in two district hospitals in the southwest of England during the period 1986-1988 were evaluated. Fifteen patients were vacationers and, as a result, were lost to followup. The operation and subsequent management was performed by more than 15 different members of the staff, of different levels of seniority and experience. The present survey in this group of surgeons has demonstrated that the dynamic axial fixator is a reliable means of treating open fractures of the tibia following an initial good reduction. It does, however, highlight the importance of the strict adherence to simple guidelines for application, pin care and dynamization if best results are to be obtained.

Double-blind- evaluation of bromperidol versus haloperidol treatment in chronic psychotic patients.

Twenty four chronic psychotic patients were assigned at random to bromperidol or haloperidol. The mean dose for bromperidol was 4 to 8 mg in one intake in the morning and for haloperidol 4 mg given twice a day. Regular evaluation was performed by BPRS, global clinical impression, side-effects scale, hematological and biochemical screening. It appears that bromperidol is a potent antipsychotic drug with a duration of 24 h. Compared to haloperidol, it favours social integration by a mild but definite activating property. No major side-effects were observed.