Pain Management — Acute and Chronic

A 58-year-old woman with chronic cancer pain is being managed with a multimodal analgesic regimen. Regarding adjuvant analgesics and non-opioid medications used in chronic pain management, all of the following are appropriate uses EXCEPT:

A 52-year-old woman with metastatic breast cancer presents to the pain clinic with severe, uncontrolled cancer pain despite adequate doses of oral morphine. Which is the most common reason for inadequate analgesia in this patient?

A 52-year-old man with a 10-year history of chronic lower back pain due to degenerative disc disease presents to the pain clinic. He has been on oral morphine 60 mg daily for the past 3 years with good pain control, but now reports breakthrough pain 3–4 times weekly despite compliance. Physical examination reveals no new neurological deficits. What is the most appropriate next step in management?

A 38-year-old woman with rheumatoid arthritis presents to the acute pain clinic with severe left knee pain (8/10) following intra-articular corticosteroid injection 48 hours ago. She reports acute swelling, warmth, and erythema over the injection site. Temperature is 37.8°C, and synovial fluid aspirate shows 45,000 WBC/μL with 80% neutrophils. Gram stain and culture are pending. What is the most appropriate immediate management?

A 52-year-old man with a 10-year history of type 2 diabetes presents to the pain clinic with chronic neuropathic pain in both feet. He describes a burning sensation with numbness and tingling. Visual analog scale (VAS) score is 8/10. He has already tried gabapentin 1800 mg/day without adequate relief. On examination, he has diminished vibration sense and absent ankle reflexes bilaterally. What is the most appropriate next step in pharmacological management?