S.M. Bierma-Zeinstra

Incidence and determinants of lower extremity running injuries in long distance runners: a systematic review

The purpose of this study was to present a systematic overview of published reports on the incidence and associated potential risk factors of lower extremity running injuries in long distance runners. An electronic database search was conducted using the PubMed–Medline database. Two observers independently assessed the quality of the studies and a best evidence synthesis was used to summarise the results. The incidence of lower extremity running injuries ranged from 19.4% to 79.3%. The predominant site of these injuries was the knee. There was strong evidence that a long training distance per week in male runners and a history of previous injuries were risk factors for injuries, and that an increase in training distance per week was a protective factor for knee injuries.

Body mass index associated with onset and progression of osteoarthritis of the knee but not of the hip: The Rotterdam Study

Objective: To investigate the relationship between body mass index (BMI) and the incidence and progression of radiological knee as well as of radiological hip osteoarthritis. Design: Cohort study. Setting: Population based. Participants: 3585 people aged ⩾55 years were selected from the Rotterdam Study, on the basis of the availability of radiographs of baseline and follow-up. Main outcome measures: Incidence of knee or hip osteoarthritis was defined as minimally grade 2 at follow-up and grade 0 or 1 at baseline. The progression of osteoarthritis was defined as a decrease in joint space width. Methods:x Rays of the knee and hip at baseline and follow-up (mean follow-up of 6.6 years) were evaluated. BMI was measured at baseline. Results: A high BMI (>27 kg/m2) at baseline was associated with incident knee osteoarthritis (odds ratio (OR) 3.3), but not with incident hip osteoarthritis. A high BMI was also associated with progression of knee osteoarthritis (OR 3.2). For the hip, a significant association between progression of osteoarthritis and BMI was not found. Conclusion: On the basis of these results, we conclude that BMI is associated with the incidence and progression of knee osteoarthritis. Furthermore, it seems that BMI is not associated with the incidence and progression of hip osteoarthritis.

Effectiveness of exercise therapy: A best-evidence summary of systematic reviews

The purpose of this project was to summarise the available evidence on the effectiveness of exercise therapy for patients with disorders of the musculoskeletal, nervous, respiratory, and cardiovascular systems. Systematic reviews were identified by means of a comprehensive search strategy in 11 bibliographic databases (08/2002), in combination with reference tracking. Reviews that included (i) at least one randomised controlled trial investigating the effectiveness of exercise therapy, (ii) clinically relevant outcome measures, and (iii) full text written in English, German or Dutch, were selected by two reviewers. Thirteen independent and blinded reviewers participated in the selection, quality assessment and data-extraction of the systematic reviews. Conclusions about the effectiveness of exercise therapy were based on the results presented in reasonable or good quality systematic reviews (quality score > or = 60 out of 100 points). A total of 104 systematic reviews were selected, 45 of which were of reasonable or good quality. Exercise therapy is effective for patients with knee osteoarthritis, sub-acute (6 to 12 weeks) and chronic (> or = 12 weeks) low back pain, cystic fibrosis, chronic obstructive pulmonary disease, and intermittent claudication. Furthermore, there are indications that exercise therapy is effective for patients with ankylosing spondylitis, hip osteoarthritis, Parkinsons disease, and for patients who have suffered a stroke. There is insufficient evidence to support or refute the effectiveness of exercise therapy for patients with neck pain, shoulder pain, repetitive strain injury, rheumatoid arthritis, asthma, and bronchiectasis. Exercise therapy is not effective for patients with acute low back pain. It is concluded that exercise therapy is effective for a wide range of chronic disorders.

Osteotomy for medial compartment arthritis of the knee using a closing wedge or an opening wedge controlled by a Puddu plate: A ONE-YEAR RANDOMISED, CONTROLLED STUDY

A prospective, randomised, controlled trial compared two different techniques of high tibial osteotomy with a lateral closing wedge or a medial opening wedge, stabilised by a Puddu plate. The clinical outcome and radiological results were examined at one year. The primary outcome measure was the achievement of an overcorrection of valgus of 4 degrees . Secondary outcome measures were the severity of pain (visual analogue scale), knee function (Hospital for Special Surgery score), and walking distance. Between January 2001 and April 2004, 92 patients were randomised to one or other of the techniques. At follow-up at one year the post-operative hip-knee-ankle angle was 3.4 degrees (+/- 3.6 degrees SD) valgus after a closing wedge and 1.3 degrees (+/- 4.7 degrees SD) of valgus after an opening wedge. The adjusted mean difference of 2.1 degrees was significant (p = 0.02). The deviation from 4 degrees of valgus alignment was 2.7 degrees (+/- 2.4 degrees SD) in the closing wedge and 4.0 degrees (+/- 3.6 degrees sd) in the opening-wedge groups. The adjusted mean difference of 1.67 degrees was also significant (p = 0.01). The severity of pain, knee score and walking ability improved in both groups, but the difference was not significant. Because of pain, the staples required removal in 11 (23%) patients in the closing-wedge group and a Puddu plate was removed in 27 (60%) patients in the opening-wedge group. This difference was significant (p < 0.001). We conclude that closing-wedge osteotomy achieves a more accurate correction with less morbidity, although both techniques had improved the function of the knee at one year after the procedure.

Do metabolic factors add to the effect of overweight on hand osteoarthritis? The Rotterdam Study

Background: As hand joints are non-weight bearing, the association between overweight and hand osteoarthritis (HOA) is critical to understanding how overweight may associate with osteoarthritis (OA) apart from axial load. Overweight might be associated with the occurrence of OA through other metabolic factors. Aim: To evaluate the role of overweight in HOA, cross-sectional data of a population-based study were used (⩾55 years, n = 3585). The role of diabetes, hypertension and total cholesterol:high-density lipoprotein (HDL)-cholesterol ratio on HOA, and whether they play an intermediate role in the association of overweight/HOA was investigated. Furthermore, the prevalence of HOA in the concurrent presence of overweight and other metabolic factors was evaluated. Results: Independently of other metabolic factors, overweight (body mass index (BMI) >27.4 kg/m2) showed a significant association with HOA (OR 1.4, 95% CI 1.2 to 1.7). The association between diabetes and HOA was only present in people aged 55–62 years (OR 1.9, 95% CI 1.0 to 3.8), but was absent in the total population or in other age groups. The association of hypertension with HOA was weak, and disappeared after adjustment for BMI. The total/HDL cholesterol ratio showed no significant association with HOA. The concurrent presence of overweight, diabetes and hypertension resulted in an even higher prevalence of HOA (OR 2.3, 95% CI 1.3 to 3.9) compared with subjects with none of these characteristics; this prevalence increased further in the younger age group (OR 3.2, 95% CI 1.1 to 8.8). Conclusion: No intermediate effect of metabolic factors on the association of overweight with HOA was found. An increase in the prevalence of HOA, however, seems to be present when overweight occurs together with hypertension and diabetes especially at a relatively young age.

Animal models for osteoarthritis: the effect of ovariectomy and estrogen treatment – a systematic approach

OBJECTIVE The prevalence of osteoarthritis (OA) increases dramatically in women after the age of 50. Animal models are used to study the effects of hormone depletion [by ovariectomy (OVX)] and estrogen treatment on OA. This review summarizes these animal studies, in order to get a better insight in the role of hormones on OA. METHOD The literature was systematically reviewed until May 2007. The results were divided into two parts: the effect of OVX on cartilage, and the effect of estrogen treatment on cartilage. Only studies with an appropriate control group (e.g., sham-operated) were included. RESULTS AND DISCUSSION Eleven out of 16 animal studies showed that OVX resulted in cartilage damage. When only studies using sexually mature animals were included, we saw that 11 out of 14 studies showed a detrimental effect, indicating considerable evidence for a relation between cartilage degeneration and OVX in mature animals. The effect of estrogen treatment was inconclusive with only 11 out of 22 animal studies reporting a beneficial effect on cartilage, whereas all six studies administering selective estrogen receptor modulators (SERMs) after OVX described protective effects. The discrepancy between the studies may be caused by the large variation in experimental set-up. We suggested a list of quality criteria for animal models since standardisation of design and outcome parameters of animal experiments may help to compare different studies and to gain better insight in the role of hormones in the osteoarthritic process.

Supervised exercise therapy versus usual care for patellofemoral pain syndrome: an open label randomised controlled trial.

Objective To assess the effectiveness of supervised exercise therapy compared with usual care with respect to recovery, pain, and function in patients with patellofemoral pain syndrome. Design Open label randomised controlled trial. Setting General practice and sport physician practice. Participants Patients with a new episode of patellofemoral pain syndrome recruited by their general practitioner or sport physician. Interventions The intervention group received a standardised exercise programme for 6 weeks tailored to individual performance and supervised by a physical therapist, and were instructed to practise the tailored exercises at home for 3 months. The control group were assigned usual care, which comprised a “wait and see” approach of rest during periods of pain and refraining from pain provoking activities. Both the intervention group and the control group received written information about patellofemoral pain syndrome and general instructions for home exercises. Main outcome measures The primary outcomes were self reported recovery (7 point Likert scale), pain at rest and pain on activity (0-10 point numerical rating scale), and function (0-100 point Kujala patellofemoral score) at 3 months and 12 months follow-up. Results A total of 131 participants were included in the study: 65 in the intervention group and 66 in the control group. After 3 months, the intervention group showed better outcomes than the control group with regard to pain at rest (adjusted difference −1.07, 95% confidence interval −1.92 to −0.22; effect size 0.47), pain on activity (−1.00, −1.91 to −0.08; 0.45), and function (4.92, 0.14 to 9.72; 0.34). At 12 months, the intervention group continued to show better outcomes than the control group with regard to pain (adjusted difference in pain at rest −1.29, −2.16 to −0.42; effect size 0.56; pain on activity −1.19, −2.22 to −0.16; effect size 0.54), but not function (4.52, −0.73 to 9.76). A higher proportion of patients in the exercise group than in the control group reported recovery (41.9% v 35.0% at 3 months and 62.1% v 50.8% at 12 months), although the differences in self reported recovery between the two groups were not statistically significant. Predefined subgroup analyses revealed that patients recruited by sport physicians (n=30) did not benefit from the intervention, whereas those recruited by general practitioners (n=101) showed significant and clinically relevant differences in pain and function in favour of the intervention group. Conclusion Supervised exercise therapy resulted in less pain and better function at short term and long term follow-up compared with usual care in patients with patellofemoral pain syndrome in general practice. Exercise therapy did not produce a significant difference in the rate of self reported recovery. Trial registration ISRCTN83938749.

Statin use is associated with reduced incidence and progression of knee osteoarthritis in the Rotterdam study

Background Osteoarthritis is the most frequent chronic joint disease causing pain and disability. Besides biomechanical mechanisms, the pathogenesis of osteoarthritis may involve inflammation, vascular alterations and dysregulation of lipid metabolism. As statins are able to modulate many of these processes, this study examines whether statin use is associated with a decreased incidence and/or progression of osteoarthritis. Methods Participants in a prospective population-based cohort study aged 55 years and older (n=2921) were included. x-Rays of the knee/hip were obtained at baseline and after on average 6.5 years, and scored using the Kellgren and Lawrence score for osteoarthritis. Any increase in score was defined as overall progression (incidence and progression). Data on covariables were collected at baseline. Information on statin use during follow-up was obtained from computerised pharmacy databases. The overall progression of osteoarthritis was compared between users and non-users of statins. Using a multivariate logistic regression model with generalised estimating equation, OR and 95% CI were calculated after adjusting for confounding variables. Results Overall progression of knee and hip osteoarthritis occurred in 6.9% and 4.7% of cases, respectively. The adjusted OR for overall progression of knee osteoarthritis in statin users was 0.43 (95% CI 0.25 to 0.77, p=0.01). The use of statins was not associated with overall progression of hip osteoarthritis. Conclusions Statin use is associated with more than a 50% reduction in overall progression of osteoarthritis of the knee, but not of the hip.

Prevalence and determinants of one month hand pain and hand related disability in the elderly (Rotterdam study)

Objective: To study the prevalence of hand pain and hand disability in an open population, and the contribution of their potential determinants. Methods: Baseline data were used from 7983 participants in the Rotterdam study (a population based study in people aged ⩾55 years). A home interview was used to determine the presence of hand pain during the previous month, rheumatoid arthritis, osteoarthritis in any joint, diabetes, stroke, thyroid disease, neck/shoulder pain, gout, history of fracture in the past five years, and Parkinson’s disease, as well as age, sex, and occupation. Hand disability was defined as the mean score of eight questions related to hand function. Body mass index was measured and hand x rays were taken. Results: The one month period prevalence of hand pain was 16.9%. The prevalence of hand disability was 13.6%. In univariate analysis for hand pain, rheumatoid arthritis had the highest explained variance (R2) and odds ratio. For hand disability, aging showed the highest explained variance and Parkinson’s disease had the highest odds ratio. All determinants together showed an explained variance of 19.8% for hand pain and 25.2% for hand disability. In multivariate analysis, positive radiographic hand osteoarthritis was a poor explanation for hand pain (R2 = 0.5%) or hand disability (R2 = 0). Conclusions: The contribution of available potential determinants in this study was about 20% for hand pain and 25% for hand disability in an unselected population of elderly people. Thus a greater part of hand pain/hand disability remains unexplained.

Prediction model for knee osteoarthritis incidence, including clinical, genetic and biochemical risk factors

Objective To develop and validate a prognostic model for incident knee osteoarthritis (KOA) in a general population and determine the value of different risk factor groups to prediction. Methods The prognostic model was developed in 2628 individuals from the Rotterdam Study-I (RS-I). Univariate and multivariate analyses were performed for questionnaire/easily obtainable variables, imaging variables, genetic and biochemical markers. The extended multivariate model was tested on discrimination (receiver operating characteristic curve and area under the curve (AUC)) in two other population-based cohorts: Rotterdam Study-II and Chingford Study. Results In RS-I, there was moderate predictive value for incident KOA based on the genetic score alone in subjects aged <65 years (AUC 0.65), while it was only 0.55 for subjects aged ≥65 years. The AUC for gender, age and body mass index (BMI) in prediction for KOA was 0.66. Addition of the questionnaire variables, genetic score or biochemical marker urinary C-terminal cross-linked telopeptide of type II collagen to the model did not change the AUC. However, when adding the knee baseline KL score to the model the AUC increased to 0.79. Applying external validation, similar results were observed in the Rotterdam Study-II and the Chingford Study. Conclusions Easy obtainable ‘Questionnaire’ variables, genetic markers, OA at other joint sites and biochemical markers add only modestly to the prediction of KOA incidence using age, gender and BMI in an elderly population. Doubtful minor radiographic degenerative features in the knee, however, are a very strong predictor of future KOA. This is an important finding, as many radiologists do not report minor degenerative changes in the knee.