Ronald Diercks
University Medical Center Groningen
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British Journal of Sports Medicine | 2010
Ida Buist; Steef W. Bredeweg; Bram Bessem; W. van Mechelen; Koen Lemmink; Ronald Diercks
Objective In this study, the incidence and the sex-specific predictors of running-related injury (RRI) among a group of recreational runners training for a 4-mile running event were determined and identified, respectively. Design Prospective cohort study. Methods Several potential risk factors were prospectively measured in 629 novice and recreational runners. They were observed during an 8-week training period for any running-related musculoskeletal injuries of the lower limbs and back. A running-related injury was defined as any musculoskeletal pain of the lower limb or back causing a restriction of running for at least 1 day. Results At least one RRI was reported by 25.9% of the runners during the 8-week observation period. The incidence of RRI was 30.1 (95% CI 25.4 to 34.7) per 1000 h of running exposure. Multivariate Cox regression showed that male participants were more prone to sustain a RRI than female participants (HR 1.4; 95% CI 1.0 to 2.0). No previous running experience was the most important risk factor in male (HR 2.6; 95% CI 1.2 to 5.5) and female (HR 2.1; 95% CI 1.2 to 3.7) participants. Conclusions The incidence of running-related injuries in recreational runners preparing for a 4-mile running event is substantially high. Male and female participants have different risk profiles. Furthermore, the findings suggest that novice runners may benefit the most out of preventive interventions for RRI.
American Journal of Sports Medicine | 2011
Johannes Zwerver; F. Hartgens; Evert Verhagen; Henk van der Worp; Inge van den Akker-Scheek; Ronald Diercks
Background: Patellar tendinopathy is a common overuse injury among jumping athletes. No evidence-based treatment guidelines exist. Extracorporeal shockwave therapy (ESWT) appears to be a promising treatment but its effectiveness has not been studied in athletes with patellar tendinopathy who have symptoms for 3 to 12 months and are still playing. Purpose: The TOPGAME study was created to determine the effectiveness of ESWT on pain, symptoms, and function in athletes with early symptomatic patellar tendinopathy who are still in training and competition. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: Athletes playing volleyball, basketball, or handball with patellar tendinopathy for 3 to 12 months were randomized into the ESWT or placebo group during the first half of the season. The ESWT group received 3 ESWT treatments while the placebo group received sham ESWT. In-season follow-up measurements were 1, 12, and 22 weeks after treatment. The primary outcome was severity of patellar tendinopathy determined with the Victorian Institute of Sport Assessment–Patella (VISA-P) questionnaire. Secondary outcome measures were pain during activities of daily living and sports and after functional knee-loading tests rated on a visual analog scale and subjective improvement. Multilevel analyses were performed to determine differences between groups over time. Results: Of the 127 symptomatic athletes invited to participate, 62 were eligible, gave consent, and were randomized into the ESWT (n = 31) or placebo group (n = 31). Mean VISA-P scores before and 1, 12, and 22 weeks after treatment were 59.4 (±11.7), 66.8 (±16.2), 66.7 (±17.5), and 70.5 (±18.9) for the ESWT group and 62.4 (±13.4), 66.3 (±19.0), 68.9 (±20.3), and 72.7 (±18.0) for the placebo group. For the VISA-P, there was a significant effect for time (P < .01) but no treatment × time interaction effect (P = .82). The same pattern was seen in visual analog scale pain scores. One week after final treatment, significantly more athletes in the ESWT group reported subjective improvement (65% vs 32%; χ2 = 6.46, P = .01). This was the only difference noted between the 2 groups. Conclusion: Extracorporeal shockwave therapy as a solitary treatment during the competitive season has no benefit over placebo treatment in the management of actively competing jumping athletes with patellar tendinopathy who have symptoms for less than 12 months.
British Journal of Sports Medicine | 2007
Denise Eygendaal; F. T. G. Rahussen; Ronald Diercks
Elbow injuries constitute a sizeable percentage of tennis injuries. A basic understanding of biomechanics of tennis and analysis of the forces, loads and motions of the elbow during tennis will improve the understanding of the pathophysiology of these injuries. All different strokes in tennis have a different repetitive biomechanical nature that can result in tennis-related injuries. In this article, a biomechanically-based evaluation of tennis strokes is presented. This overview includes all tennis-related pathologies of the elbow joint, whereby the possible relation of biomechanics to pathology is analysed, followed by treatment recommendations.
Journal of Shoulder and Elbow Surgery | 2015
Frederik O. Lambers Heerspink; Jos J.A.M. van Raay; Rinco C.T. Koorevaar; Pepijn J.M. van der Eerden; Robin E. Westerbeek; Esther van 't Riet; Inge van den Akker-Scheek; Ronald Diercks
BACKGROUNDnGood clinical results have been reported for both surgical and conservative treatment of rotator cuff tears. The primary aim of this randomized controlled trial was to compare functional and radiologic improvement after surgical and conservative treatment of degenerative rotator cuff tears.nnnMETHODSnWe conducted a randomized controlled trial that included 56 patients with a degenerative full-thickness rotator cuff tear between January 2009 and December 2012; 31 patients were treated conservatively, and rotator cuff repair was performed in 25 patients. Outcome measures, including the Constant-Murley score (CMS), visual analog scale (VAS) pain and VAS disability scores, were assessed preoperatively and after 6 weeks and 3, 6, and 12 months. Magnetic resonance imaging was performed preoperatively and at 12 months postoperatively.nnnRESULTSnAt 12 months postoperatively, the mean CMS was 81.9 (standard deviation [SD], 15.6) in the surgery group vs 73.7 (SD, 18.4) in the conservative group (P = .08). VAS pain (P = .04) and VAS disability (P = .02) were significantly lower in the surgery group at the 12-month follow-up. A subgroup analysis showed postoperative CMS results were significantly better in surgically treated patients without a retear compared with conservatively treated patients (88.5 [SD, 6.2] vs 73.7 [SD, 18.4]).nnnCONCLUSIONnIn our population of patients with degenerative rotator cuff tears who were randomly treated by surgery or conservative protocol, we did not observe differences in functional outcome as measured with the CMS 1 year after treatment. However, significant differences in pain and disabilities were observed in favor of surgical treatment. The best outcomes in function and pain were seen in patients with an intact rotator cuff postoperatively.
International Journal of Sports Medicine | 2014
Henk van der Worp; H. J. de Poel; Ronald Diercks; I. van den Akker-Scheek; Johannes Zwerver
Patellar tendinopathy (jumpers knee) is a common injury in sports that comprise jump actions. This article systematically reviews the literature examining the relation between patellar tendinopathy and take-off and landing kinematics in order to uncover risk factors and potential prevention strategies. A systematic search of the Pubmed, Embase and Amed databases was performed to identify studies that reported kinematics of sport specific jumps in relation to patellar tendinopathy. A quantitative analysis was performed on 4 indentified studies. Differences were found only between controls and asymptomatic subjects with patellar tendon abnormalities. Most differences were found during horizontal landing after forward acceleration. A synthesis of the literature suggests that horizontal landing poses the greatest threat for developing patellar tendinopathy. A stiff movement pattern with a small post-touchdown range of motion and short landing time is associated with the onset of patellar tendinopathy. Accordingly, employing a flexible landing pattern seems to be an expedient strategy for reducing the risk for (re-) developing patellar tendinopathy. Together, these findings indicate that improving kinetic chain functioning, performing eccentric exercises and changing landing patterns are potential tools for preventive and/or therapeutic purposes.
Scandinavian Journal of Medicine & Science in Sports | 2015
A P.J. de Vries; H. van der Worp; Ronald Diercks; I. van den Akker-Scheek; Johannes Zwerver
Patellar tendinopathy (PT) is a common overuse injury of the patellar tendon in jumping athletes. In a recent large cross‐sectional study from 2008 several factors were identified that may be associated with the etiology of PT. However, because of the study design no conclusions could be drawn about causal relations. The primary aim of the current study is to investigate whether the factors identified in the previous 2008 study can also be prospectively recognized as predictors of symptomatic PT in 2011. Nine hundred twenty‐six Dutch elite and non‐elite basketball and volleyball players from the previous study were invited again to complete an online survey about knee complaints and risk factors for PT in 2011. The logistic regression included 385 athletes of which 51 (13%) developed PT since 2008. Male gender [odds ratio (OR) 2.0, 95% confidence interval (CI) 1.1–3.5] was found to be a risk factor for developing PT. No sports‐related variables could be identified to increase the risk of developing PT, but some evidence was found for performing heavy physically demanding work, like being a nurse or a physical education teacher (OR 2.3, 95% CI 0.9–6.3). These findings indicate that, when considering preventive measures, it is important to take into account the total tendon load.
Journal of Science and Medicine in Sport | 2016
Janne A. Peters; Johannes Zwerver; Ronald Diercks; Marije T. Elferink-Gemser; Inge van den Akker-Scheek
OBJECTIVESnTendinopathy, the most prevalent tendon disorder which is considered as the clinical diagnosis of pain and dysfunction, is common in sports and its prevalence is ever-increasing. Despite the lack of clarity about risk factors, various preventive interventions for tendinopathy have been investigated. The main objective of this study is to review current preventive interventions for tendinopathy in the major regions: ankle, knee, hip, groin, shoulder and elbow.nnnDESIGNnA systematic literature search was conducted.nnnMETHODSnThe PubMed and Embase databases were explored to identify articles that met the inclusion criteria. The included studies were assessed on methodological quality and data was summarized.nnnRESULTSnTen articles were included that describe a wide variety of preventive interventions. These were divided into three categories: stretch and exercise interventions, shoe adaptations and other interventions. The methodological quality of the studies was moderate to high. Three out of ten studies showed a significant beneficial result.nnnCONCLUSIONSnThere is limited evidence that a long-term intervention including balance training is effective in the prevention of patellar and Achilles tendinopathy. Shoe adaptations in the form of shock absorbing insoles could have a preventive effect on Achilles tendinopathy. Hormone replacement therapy seems to reduce the risk for structural Achilles tendon changes in active post-menopausal women. No evidence was found for a positive effect of stretching exercises. Prophylactic eccentric training and stretching can increase the risk of injury in asymptomatic players with patellar tendon abnormalities. A limited amount of studies was available and more research is needed on (multifactorial) etiology, risk factors and preventive interventions.
Scandinavian Journal of Medicine & Science in Sports | 2015
Bas Kluitenberg; M. van Middelkoop; Dirk-Wouter Smits; Evert Verhagen; F. Hartgens; Ronald Diercks; H. van der Worp
Running is a popular form of physical activity, despite of the high incidence of running‐related injuries (RRIs). Because of methodological issues, the etiology of RRIs remains unclear. Therefore, the purposes of the study were to assess the incidence of RRIs and to identify risk factors for RRIs in a large group of novice runners. In total, 1696 runners of a 6‐week supervised “Start to Run” program were included in the NLstart2run study. All participants were aged between 18 and 65, completed a baseline questionnaire that covered potential risk factors, and completed at least one running diary. RRIs were registered during the program with a weekly running log. An RRI was defined as a musculo‐skeletal complaint of the lower extremity or back attributed to running and hampering running ability for three consecutive training sessions. During the running program, 10.9% of the runners sustained an RRI. The multivariable Cox regression analysis showed that a higher age, higher BMI, previous musculo‐skeletal complaints not attributed to sports and no previous running experience were related to RRI. These findings indicate that many novice runners participating in a short‐term running program suffer from RRIs. Therefore, the identified risk factors should be considered for screening and prevention purposes.
Clinical Orthopaedics and Related Research | 2008
Gunnar Flivik; Ronald Diercks; Nicolaas Jacobus Joseph Verdonschot
Wear curves from individual patients often show unexplained irregular wear curves or impossible values (negative wear). We postulated errors of two-dimensional wear measurements are mainly the result of radiographic projection differences. We tested a new method that makes two-dimensional wear measurements less sensitive for radiograph projection differences of cemented THAs. The measurement errors that occur when radiographically projecting a three-dimensional THA were modeled. Based on the model, we developed a method to reduce the errors, thus approximating three-dimensional linear wear values, which are less sensitive for projection differences. An error analysis was performed by virtually simulating 144 wear measurements under varying conditions with and without application of the correction: the mean absolute error was reduced from 1.8xa0mm (range, 0–4.51xa0mm) to 0.11xa0mm (range, 0–0.27xa0mm). For clinical validation, radiostereometric analysis was performed on 47 patients to determine the true wear at 1, 2, and 5xa0years. Subsequently, wear was measured on conventional radiographs with and without the correction: the overall occurrence of errors greater than 0.2xa0mm was reduced from 35% to 15%. Wear measurements are less sensitive to differences in two-dimensional projection of the THA when using the correction method.
Scandinavian Journal of Medicine & Science in Sports | 2016
A. de Vries; Johannes Zwerver; Ronald Diercks; Igor Tak; S. van Berkel; R. van Cingel; H. van der Worp; I. van den Akker-Scheek
Numerous athletes with patellar tendinopathy (PT) use a patellar strap or sports tape during sports. This studys aim was to investigate the short‐term effect of these orthoses on patellar tendon pain. Participants performed the single‐leg decline squat, vertical jump test, and triple‐hop test under four different conditions (patellar strap, sports tape, placebo, and control). Subsequently, participants practiced sports as usual for 2 weeks; during 1 week, they were assigned to one of the four conditions. Pain was measured with the visual analog scale (VAS). In total, 97 athletes with PT [61% male, age 27.0 (SD8.1), VISA‐P 58.5 (SD12.7)] were analyzed. On the single‐leg decline squat, the VAS pain score reduced significantly in the patellar strap (14u2009mm, Pu2009=u20090.04) and the sports tape condition (13u2009mm, Pu2009=u20090.04), compared with control, but not placebo. A significant decrease in VAS pain during sports was found in the sports tape (7u2009mm, Pu2009=u20090.04) and placebo group (6u2009mm, Pu2009=u20090.04). The VAS pain score two hours after sports decreased significantly in the patellar strap, sports tape and placebo group (8‐mm, Pu2009<u20090.001, 10u2009mm, Pu2009=u20090.001 and 7u2009mm, Pu2009=u20090.03, respectively). This studys findings indicate that an orthosis (including placebo tape) during sports can reduce pain in PT patients in the short term.