"Unlike drugs, implants don’t need to go through clinical trials in most cases."

The artical says "surgical innovations" which probably means instruments and procedures. Also "some implants" are exempt from showing efficacy in clinical trials under HDE for cases in which the patient would have died anyway (e.g. pacemakers).

All medical devices of Class 2 and 3 must go through clinical trials to prove safety and efficacy as part of the FDA IDE. Spinal implants would certainly be Class 3.

Edit: clarification