Yes they can do that provided that is in accordance with the terms of your contact. However if you can reclaim this money you have lost by way of a personal injury claim.
In terms of personal injury law, you have 3 years from the date of the injury, or you "reasonably became aware" of the injury to raise a claim. In this type of claim you are provided some compensation for the injury itself. On top of this, you can claim for loss of earnings you have incurred and also any costs/expenses incurred as a direct relation to the injury this would include cost such as the cost of attending hospital appointments and lost wages as a result. This is usually an insurance claim, but the claim is made directly to your employer. There are usually a few high street law firms who will take this type of claim on with a no win no fee basis.
I shall provide you with a helpful link that will assist you in finding a solicitor/representative near your local area. This will provide you with someone nearby your area who can assist you if required.
I hope this information proved helpful. You will find a local solicitor who deals with these matters on the law society webpage which is as follows;
https://www.lawsoc-ni.org/solicitors (N. Ireland)
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