Maybe records of all previous surgery visits health issues in order to hep establish the starting point for a 'before accident' and 'post accident' comparison. May also be a collection of photos and x rays
I guess on your condition pre / post accident and any underlying medical conditions you may have had. solicitors charge by 0.1 of the hour, so hope you aren't not paying her fees to read your medical life history. In reality it won't be your solicitor reading all of your notes, more likely a junior member staff, who will point out anything of consequence to your solicitor. Why not ask your solicitor why she needs all of your notes?
The whole medical notes are absolutely essential if your case goes to court. The medical expert will go through your note with a tooth and comb to find a reason, in the past, that pre-dates your accident which could dissociate your symptoms from your accident, thus invalidating or at least diminishing the veracity of your claim.