Australian researchers have queried the long-term safety of painkilling injections administered in professional sport to enable injured players to immediately return to the field.

In a systematic review, they found an association between injections to knee joints, thumbs, wrists and ankles and later complications.

However, injections to the acromioclavicular or sternoclavicular joints appeared to be safe over the medium-term.

The authors, from the University of Sydney, said: “The most remarkable finding, given the wide use of the practice, was the dearth of relevant studies to review — only 10.”