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I also had a quick and somehow painless recovery, which Im sure much of that can be owed to his excellent surgical technique

Nerve damage and neuropathy
(Others have suggested that the lipid nanoparticle is responsible for these severe, but transient, side effects reported in some trial participants.)

doi: 10.1016/j.tcb.2020.04.004

Froese DS, Fowler B, Baumgartner MR
The most important thing to remember is to find a site thats comfortable for you, and develop methods where you will be certain to avoid contact with bone