Apparently you have already spoken to some lawyers and they have told you the case looks very tough, maybe impossible to prove. Medical malpractice cases require proof of substandard care causing an injury. There is an injury, but the other pieces of the puzzle seem to be missing. In certain very limited circumstances, failure to maintain records can work against a defendnat, but there has to be some proof of fault independent of the records before that rule applies. The best advice I can give your husband is to try to find good medical help for the broken hardware. I am not giving medical advice, but If the old broken hardware is removed, that could provide some clues as to what went wrong. Make sure the removed hardware is not discarded or the problems of proof will just get worse.
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