Bit confused by the timeline was it:

Friday injured, Monday compression bandage, Saturday pain, Sunday X-Ray

or

Friday injured, Staurday pain, Sunday X-Ray, Monday compression bandage

Either way report the facts, not the suspicions

RTrueman - this is the sort of injury the severity of which doesn't always present immediately. Something similar has happened to someone in my family in the last month.

For anyone who watches free to air news, they should know that the NHS is struggling and so perhaps more than usual, people are reluctant to seek attention either as they don't want to be waiting in queue for hours and hours and/or they don't want to put more pressure on the NHS.

So, unless you have some real reason to believe your employee is lying about the circumstances of their injury why would you want to question what they are saying?

As has been said numerous times on these forums, reporting a "RIDDOR" is NOT an admission of liability - RIDDOR is just an administrative mechanism that helps inform the authorities about certain types of incident. 

OK, if your site has one of those boards which records the number of days since the last RIDDOR or whatever, you may have to reset it and consider whether it really adds value, or rather whether it discourages reporting.

...and what you have been told (true or not) gives you an opportunity to revisit your risk assessment and consider whether the job could be done more safely, so far as reasonably practicable. May be not - so you put it down to an accident that could not have reasonably been prevented. But that depends on issues such as the dimensions of the workpieces being handled, how often and other variables.

As to your rule about "every accident must be reported", it's unlikely that it's taken as universal. Otherwise, everytime someone e.g. trips and twists their ankle, you are going to have loads and loads of reports of near misses that are unlikely to be particularly helpful in informing your management of health, safety and welfare issues at your workplace, but may divert lots of resources that could be better applied.

One of those rules that is often unearthed with the benefit of hindsight!

If the IP had not turned up for work or asked for specific change of duties I would have questioned it...the person sounds genuine and is still working so I am not seeing a problem here...RIDDOR as stated and investigate...factually and try and keep objective or you could actually find that you change the attitude of the worker to either not report or not turn up with even the most minor of injury..everyone gets 2 changes but the third..