A minimally invasive facet joint hemi-arthroplasty method using a unique metallic overlay, instrumentation and surgical protocol to resurface the superior facet of the inferior vertebrae limited to the facet joints located on the lumbar spine, Occiput-C1 through L5-S1. Using related new instrumentation and a surgical protocol invented to prepare the joint, a metallic overlay is mechanically crimped in place without the use of cement or pedicle screws. Permanent fixation occurs when bone in-grows onto a rough, porous surface on the inside of the implant. This hemi-arthroplasty method resurfaces half of the facet joint to provide for smooth, pain free joint articulation in deteriorated or diseased spinal facet joints without the need for major surgery or rehabilitation at considerably less risk to the patient. This procedure may also be used to prophylactically resurface the joint to minimize or eliminate future deterioration caused by the additional stress to facet joints from disc replacements or instrumented vertebral fusion. Instrumentation includes a newly invented planer, director probe with slap-hammer, vertebral separator, osteotome, broach, crimper and facet joint prosthetic implant for use in surgically resurfacing facet joints located from Occiput-C1 through L5-S1 using a minimally invasive outpatient facet joint hemi-arthroplasty method developed specifically for that purpose.