D. Van Tiggelen

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.

Effect of bracing on the prevention of anterior knee pain—a prospective randomized study

There have been numerous reports about the use of knee braces to prevent traumatic knee injuries. Despite the frequent use of braces, very few prospective studies have been performed to study the effect of knee braces for preventing anterior knee pain syndrome (AKPS). The purpose of this study was to assess the effectiveness of a dynamic patellofemoral brace (On-Track System, dj Orthopedics) in the prevention of AKPS. 167 military recruits without history of knee pain were randomized into two groups prior to the start of their 6-week basic military training (BMT) program. The first group (brace group) consisted of 54 recruits who wore the braces for all physical activities during these 6 weeks. 113 recruits served as a control group, and followed the same 6-week strenuous training program. Chi square statistics (Fisher exact test) were used to compare the number of AKPS patients in the brace group and in the non-brace group. Our results indicated that recruits in the brace group appeared to develop significantly less anterior knee pain compared to the recruits in the control group (p =0.020). Out of the 54 recruits in the brace group, ten (18.5%) developed anterior knee pain during this study. In the control group (n =113), 42 recruits (37%) developed anterior knee pain. We conclude that the result of the present study suggests that the use of a dynamic patellofemoral brace is an effective way to prevent the development of anterior knee pain in persons undergoing a strenuous training program.

The use of a neoprene knee sleeve to compensate the deficit in knee joint position sense caused by muscle fatigue.

The importance of good proprioceptive abilities is stressed in many rehabilitation protocols. In contrast, it has been shown that muscle fatigue has a negative influence on proprioception. The objective of this study was to evaluate the effects of a neoprene knee sleeve (NKS) on the joint position sense in a fatigued knee joint. Sixty‐four healthy subjects underwent four successive assessments of the same active joint repositioning test (AJRT) in an open kinetic chain setting under different conditions. First, each subject performed the AJRT without brace. One knee was braced during the second assessment. Subjects wore the brace for 6 h and were submitted to a fatigue protocol, followed by the third assessment under the same conditions as the previous one. The fourth and last AJRT was performed immediately after the third one but both knees were non‐braced. When the subjects wore an NKS, significant differences in repositioning error were demonstrated between both sides. On the braced side, no significant differences were observed between the baseline assessment and the third assessment. NKS compensate the deficit in joint position sense due to fatigue. The use of NKS could be justified as a preventive measure or treatment in subjects to enhance proprioception.

What does normal tendon structure look like? New insights into tissue characterization in the Achilles tendon

Recently, ultrasound tissue characterization (UTC) was introduced as a reliable method for quantification of tendon structure. Despite increasing publications on the use of UTC, it is striking that there is a lack of normative data in active adolescents. Therefore, the aim of this study was to provide normative values of the Achilles tendon as quantified by UTC. Seventy physiotherapy students (26 male and 44 female students) with no history of Achilles tendon injuries were recruited. The Achilles tendons were scanned with UTC to characterize tendon structure. This study demonstrated that Achilles tendons of active, healthy adolescents contained 54.6% echo type I, 42.8% echo type II, 2.2% echo type III, and 0.3% echo type IV at midportion. The comparison between insertion and midportion of the tendon showed more echo type II at insertion (P < 0.001). Furthermore, female tendons contained significantly more echo type II, in both insertion and midportion compared with male tendons (P = 0.004 and P = 0.003, respectively). The results of this study, with respect to the MDC (minimum detectable change), highlight differences in the UTC echopattern in the normal population (sex and regional location), which are important considerations for future studies.

Blood Flow of the Achilles Tendon During Military Training

The purpose of this study was to evaluate the vascular response of the Achilles tendon as indicated by power Doppler activity during a military training program of 6 weeks. 49 male military recruits (98 tendons) volunteered for this study. Before and during the military training program, the Achilles tendons were screened with gray-scale ultrasonography and power Doppler US. Reactive tendinopathies of the Achilles tendons were registered by means of a clinical examination, VAS-scores and VISA-A scores. The US examination, the clinical examination, VAS-scores and VISA-A scores showed that 13/98 tendons developed a reactive tendinopathy. 3 of these 13 symptomatic tendons showed intratendinous Doppler activity. In these tendons, pain was always present before the vascular response of the Achilles tendon. Both pain and hypervascularisation remained visible till the end of the basic military training. In 5 asymptomatic tendons with no structural changes of the tendon, a vascular response was seen during one single measurement. It can be hypothesized that there is no relationship between the vascular response of the Achilles tendon and the pain in a reactive tendinopathy. In a reactive tendinopathy, other pain mechanisms must be investigated in future research.

Intrinsic risk factors and the effects of prophylactic bracing on the development of patellofemoral pain in male subjects

Background The aetiology of patellofemoral pain (PFP) is multifactorial. Patellofemoral bracing can be used as a preventative method in subjects undergoing strenuous training. Objective Individuals with intrinsic risk factors for PFP could be identified to provide them with patellofemoral braces as preventative method. Setting Military cadets undergo a strenuous basic military training (BMT) of 6 weeks. Design A prospective cohort study. Participants 169 male officer cadets volunteered for the study. Intervention 43 subjects were randomly assigned to the intervention group wearing patellofemoral braces during the BMT. Main outcome measurements Peak torque of the knee extensor and flexors, the onset of the VMO and VL, the joint position sense (JPS) of the knee, the range of motion and anthropometrical characteristics were measured. A military physical fitness test (MPFT) was assessed prior to the start of their BMT. Results After BMT less recruits in the brace group developed PFP compared to the control subjects (16.3% vs 33.7%; p=0.042). A delayed onset of the VMO-VL, poor JPS, lower peak torque of the knee extensors and a low score on the MPFT were predictive variables in the development of PFP. Conclusion The incidence of PFP in predisposed individuals could be downsised using patellofemoral bracing if intrinsic risk factors are identified. Physical intrinsic risk factors predict the development of PFP during strenuous training sessions. The use of the logistic regression model could identify individuals who could derive benefit from patellofemoral bracing during exacting training sessions.

Kinematic chain related risk factors in the development of lower extremity injuries in women: A prospective study

The link between dynamic range of motion (dROM) parameters within the kinematic chain and the development of lower extremity (LE) injury has gained attention; however, very few longitudinal studies have been conducted. Therefore, we wanted to prospectively determine dROM‐related risk factors for the development of LE injury. Within this study, 90 female physical education students aged 19.33±0.87 years were tested. Full‐body kinematic and vertical ground reaction force (VGRF) parameters were measured during a triple hop jump (THJ). Cox regression analysis was used to identify potential risk factors for the development of LE injury. The injury follow‐up was assessed using a weekly online questionnaire and a tri‐monthly retrospective control questionnaire. Lower extremity injury was diagnosed by an experienced medical doctor. During the follow‐up, 39 percent of the participants were diagnosed with a LE injury. Decreased dROM of the pelvic segment (P=.043) and increased dROM of the knee and ankle joint (P=.041 and P=.028, respectively) in the sagittal plane during landing phase were identified as predictive parameters for the development of LE injury in women. No VGRF parameters were identified as predictive variables. It can be concluded that an altered dROM within the LE kinematic chain was observed within the group at risk for LE injury. More specifically, this group showed reduced proximal dROM that was coupled with increased dROM in the distal segments during a THJ. The THJ can be seen as a practical screening tool for LE injury.