Background Few evidence-based treatment guidelines for tendinopathy exist. We undertook a systematic review of
randomised trials to establish clinical effi cacy and risk of adverse events for treatment by injection.
Methods We searched eight databases without language, publication, or date restrictions. We included randomised
trials assessing effi cacy of one or more peritendinous injections with placebo or non-surgical interventions for
tendinopathy, scoring more than 50% on the modifi ed physiotherapy evidence database scale. We undertook metaanalyses
with a random-eff ects model, and estimated relative risk and standardised mean diff erences (SMDs). The
primary outcome of clinical effi cacy was protocol-defi ned pain score in the short term (4 weeks, range 0–12),
intermediate term (26 weeks, 13–26), or long term (52 weeks, ≥52). Adverse events were also reported.
Findings 3824 trials were identifi ed and 41 met inclusion criteria, providing data for 2672 participants. We showed
consistent fi ndings between many high-quality randomised controlled trials that corticosteroid injections reduced
pain in the short term compared with other interventions, but this eff ect was reversed at intermediate and long
terms. For example, in pooled analysis of treatment for lateral epicondylalgia, corticosteroid injection had a large
eff ect (defi ned as SMD>0·8) on reduction of pain compared with no intervention in the short term (SMD 1·44,
95% CI 1·17–1·71, p<0·0001), but no intervention was favoured at intermediate term (–0·40, –0·67 to –0·14,
p<0·003) and long term (–0·31, –0·61 to –0·01, p=0·05). Short-term effi cacy of corticosteroid injections for rotatorcuff
tendinopathy is not clear. Of 991 participants who received corticosteroid injections in studies that reported
adverse events, only one (0·1%) had a serious adverse event (tendon rupture). By comparison with placebo,
reductions in pain were reported after injections of sodium hyaluronate (short [3·91, 3·54–4·28, p<0·0001],
intermediate [2·89, 2·58–3·20, p<0·0001], and long [3·91, 3·55–4·28, p<0·0001] terms), botulinum toxin (short
term [1·23, 0·67–1·78, p<0·0001]), and prolotherapy (intermediate term [2·62, 1·36–3·88, p<0·0001]) for treatment
of lateral epicondylalgia. Lauromacrogol (polidocanol), aprotinin, and platelet-rich plasma were not more effi cacious
than was placebo for Achilles tendinopathy, while prolotherapy was not more eff ective than was eccentric exercise.
Interpretation Despite the eff ectiveness of corticosteroid injections in the short term, non-corticosteroid injections
might be of benefi t for long-term treatment of lateral epicondylalgia. However, response to injection should not be
generalised because of variation in eff ect between sites of tendinopathy.
Funding None. © 2010 Elsevier Ltd.