How to get rid of flat discolored scars that have shiny texture?

Medical microneedling, also called fractional microneedle therapy and sometimes Dermarolling can be quite helpful for improving the color and surface texture of a whole variety of scars, regardless of the underlying cause. These include traumatic scars, surgical scars, and those of infectious origins.The procedure, performed under local anesthesia involves the use of a device that contains multiple sterile stainless steel surgical needles that penetrate to scar to form microscopic wounds. The newly created wounds set up a cascade of healing that results in new, fresh collagen formation with resultant improvement in both scar texture and surface color. Best improvement is generally achieved after a series of two to four treatment sessions spaced at six week intervals. 

A combination of pulsed dye laser + Melarase creams can help soothe out the color differential. Our office specializes in scar treatment in Los Angeles.Raffy Karamanoukian MD FACS

When assessing a scar there are a variety of features your doctor will assess in order to come up with the best plan for your scar. For example, I first start by examining the scar, noting the area of the body it involves, and determining the patient's skin type. Next, I see if the scar has any increased thickness (hypertrophy), thinness (atrophy), is flat, or a has a combination of these features. I then look at the texture of the scar, it can be smooth, finely wrinkled, coarse, or a combination of these features.  Finally, I look at the color of the scar. Is it skin colored, white, brown, red, pink, tan, purple, or a combination of these colors. There are a variety of treatment options available to improve the appearance of a scar; however, it is not possible to completely remove a scar. To help improve the appearance of a red or purple colored scar, a vascular laser such as a Pulsed Dye Laser (PDL) or Intense Pulsed Light (IPL) may be used to decrease the red to purple hue. If there are prominent textural changes, a fractionated resurfacing laser may be used. For excessive thickness (hypertrophy) of a scar your doctor may add injections such as steroids, recommend silicone sheeting, pulsed dye laser, and/or a fractionated resurfacing laser. For scars which are thin and atrophic options include: fractionated lasers to stimulate collagen production or injectable fillers. Finally scars which have increased pigment can be improved with a skin brightening skin care regimen, a series of chemical peels, fractionated resurfacing laser, and/or IPL treatments. As many patients often have multiple features to their scars, I often develop a treatment plan using a combination of the above therapies for optimal improvement of my patient's scar.  Warm regards, Dr. Peterson

It sounds like scar hypertrophy.  You can never get rid of a scar from a full thickness injury.  There are methods which may help.  Have you tried silicone gel or sheeting?  Next step would be steroid injections into the scar.  After that, the discussion comes down to the laser v. excision and reclosure. Photographs would be beneficial.