Our patient, a 52-year-old male (165 cm, 90 kg), was a known case of chronic lymphocytic leukemia (CLL, Rai Stage II). He had received two cycles of bendamustine and rituximab-based chemotherapy in two consecutive months. He developed herpes zoster infection in the following month and was started on oral acyclovir after consultation with a dermatologist. One week later, he visited our pain clinic and complained of severe pain on the right side of his lower back []. The pain was burning in nature and was associated with allodynia and restricted mobility. A diagnosis of PNH was made, and he was started on gabapentin in view of neuropathic nature of pain. The dermatomal distribution of the pain was from T11 to S1. The pain was affecting the quality of life of the patient and the pharmacological therapy was inadequate.\nWe decided to perform a right-sided ESPB in prone position for acute pain relief of the patient. A high-frequency linear ultrasound probe was placed in longitudinal orientation, about 3 cm lateral to the spinous process of the third lumbar vertebra. The interfacial plane below the erector spinae muscle was identified, and 0.25% bupivacaine and triamcinolone 40 mg (total volume 30 ml) were injected []. Patient's NRS score was decreased from 8/10 to 3/10 30 min after the block procedure. Later on, the ESPB was performed two times for 2 weeks and provided effective analgesia for the PHN. The patient reported a decline in pain score and analgesics consumption in follow-up clinics.
Case 3: A 26 years old female (weight 47 kg, ASA status II) was scheduled for left total hip arthroplasty. She was diagnosed with ankylosing spondylitis 14 years ago, with pain on almost all major joints of her body. She could not stand or walk because of bilateral femoral head necrosis. She had a family history of ankylosing spondylitis, with her father also suffered from this disease. Physical examination revealed rigidity of neck and left hip joint. X-ray of the thoracic and lumbar vertebrae reported rigidity of the spine, calcification of interspinous ligament. X-ray of bilateral sacra-iliac joints, hip joints, knees and ankles reported narrow joint space, osteoproliferation, bone defect and joint deformity. The chest X-ray reported texture enhancement of bilateral lungs and infection of right lower lobe.