Jan A.N. Verhaar

OBJECTIVE: To investigate the incidence and prevalence of shoulder complaints in the general population. METHOD: A systematic review of the literature was conducted. Medline, Embase, and Cinahl were searched for relevant studies. RESULTS: Eighteen studies on prevalence and one study on incidence met the inclusion criteria. Incidence figures of 0.9-2.5% were found for different age groups. Prevalence figures differed from 6.9 to 26% for point prevalence, 18.6-31%, for 1-month prevalence, 4.7-46.7% for 1-year prevalence and 6.7-66.7% for lifetime prevalence. Prevalence rates decreased when the case definition was restricted, in terms of duration of pain or the presence of limited movements, and increased when the location for pain was enlarged. CONCLUSION: The reported prevalence figures on shoulder complaints diverged strongly. Health professionals and policymakers who estimate the amount of medical care needed and related costs should be aware of the variations in prevalence rate and the underlying reasons for these differences.

CONTEXT: Tendon disorders comprise 30% to 50% of all activity-related injuries; chronic degenerative tendon disorders (tendinopathy) occur frequently and are difficult to treat. Tendon regeneration might be improved by injecting platelet-rich plasma (PRP), an increasingly used treatment for releasing growth factors into the degenerative tendon. OBJECTIVE: To examine whether a PRP injection would improve outcome in chronic midportion Achilles tendinopathy. DESIGN, SETTING, AND PATIENTS: A stratified, block-randomized, double-blind, placebo-controlled trial at a single center (The Hague Medical Center, Leidschendam, The Netherlands) of 54 randomized patients aged 18 to 70 years with chronic tendinopathy 2 to 7 cm above the Achilles tendon insertion. The trial was conducted between August 28, 2008, and January 29, 2009, with follow-up until July 16, 2009. INTERVENTION: Eccentric exercises (usual care) with either a PRP injection (PRP group) or saline injection (placebo group). Randomization was stratified by activity level. MAIN OUTCOME MEASURES: The validated Victorian Institute of Sports Assessment-Achilles (VISA-A) questionnaire, which evaluated pain score and activity level, was completed at baseline and 6, 12, and 24 weeks. The VISA-A score ranged from 0 to 100, with higher scores corresponding with less pain and increased activity. Treatment group effects were evaluated using general linear models on the basis of intention-to-treat. RESULTS: After randomization into the PRP group (n = 27) or placebo group (n = 27), there was complete follow-up of all patients. The mean VISA-A score improved significantly after 24 weeks in the PRP group by 21.7 points (95% confidence interval [CI], 13.0-30.5) and in the placebo group by 20.5 points (95% CI, 11.6-29.4). The increase was not significantly different between both groups (adjusted between-group difference from baseline to 24 weeks, -0.9; 95% CI, -12.4 to 10.6). This CI did not include the predefined relevant difference of 12 points in favor of PRP treatment. CONCLUSION: Among patients with chronic Achilles tendinopathy who were treated with eccentric exercises, a PRP injection compared with a saline injection did not result in greater improvement in pain and activity. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00761423.

BACKGROUND: Achilles tendon disorders, like Achilles tendinopathy, are very common among athletes. In the general population, however, knowledge about the incidence of Achilles tendinopathy is lacking. Design Cross-sectional study. METHODS: In a cohort of 57.725 persons registered in primary care, the number of patients visiting the general practitioner (GP) with diagnosis of mid-portion Achilles tendon problems was counted using computerised registration networks of GPs in 2009. Subsequently, the authors assessed associations of these rates with demographic characteristics. RESULTS: The incidence rate of Achilles tendinopathy is 1.85 per 1,000 Dutch GP registered patients. In the adult population (21-60 years), the incidence rate is 2.35 per 1,000. In 35% of the cases, a relationship with sports activity was recorded. CONCLUSION: This is the first report on incidence rates of mid-portion Achilles tendinopathy in general practice. With an incidence of 1.85 per 1,000 registered persons, Achilles tendinopathy is frequently seen by GPs. The actual incidence might even be higher due to study limitations. More research on the frequency of this injury is required.