Eighteen years ago, when she was in her early 30s, Cindy Steinberg severely injured her back at work when an unsecured filing cabinet and the cubicle walls stacked behind it fell on her. Although the diagnosis for the product development manager at a learning-technology company just outside Harvard Square was torn ligaments and damaged nerves — between thoracic disc levels 7 and 10 — it took five years for doctors to find an effective combination of treatments for her chronic pain, including an opioid pain reliever called Lortab, which is similar to Vicodin. “I was in total disbelief that I could be in this much pain and there wasn’t anyone or anything that could really help me,” says Steinberg. Doctors treated her in a “demeaning, disbelieving, dismissive, and distrustful” manner, she adds.