title: Outcomes and cost-effectiveness of carpal tunnel injections using sonographic needle guidance.
abstract: This randomized controlled study addressed whether sonographic needle guidance affected the outcomes of corticosteroid injection for symptomatic carpal tunnel syndrome. Seventy-seven symptomatic carpal tunnels were randomized to injection by either (1) conventional anatomic landmark palpation-guided injection or (2) sonographic image-guided injection, each using a two-step technique where 3 ml of 1% lidocaine was first injected to hydrodissect and hydrodisplace critical intra-carpal tunnel structures followed by injection with 80 mg of triamcinolone acetonide (2 ml). Baseline pain, procedural pain, pain at outcome (2 weeks and 6 months), responders, therapeutic duration, total cost, and cost per responder were determined. There were no complications in either treatment group. Relative to conventional anatomic landmark palpation-guided methods, sonographic guidance for injection of the carpal tunnel resulted in 77.1% reduction in injection pain (p<0.01), a 63.3% reduction in pain scores at outcome (p<0.014), 93.5% increase in the responder rate (p<0.001), 84.6% reduction in the non-responder rate (p<0.001), a 71.0% increase in therapeutic duration (p<0.001), and a 59.3% ($150) reduction in cost/responder/year for a hospital outpatient (p<0.001). However, despite improved outcomes, cost per patient per year was significantly increased for an outpatient in a physician's office and was neutral for a hospital outpatient. Sonographic needle guidance significantly improves the performance and clinical outcomes of injection of the carpal tunnel and is cost-effective for a hospital-based practice, but based on current reimbursements, it significantly increases overall costs for medical care delivered in a non-hospital-based physician practice.
authors.affiliation: Rheumatology and Clinical Immunology Division, University of New Mexico, 2211 Lomas Blvd., Albuquerque, NM, 87106, USA.
authors.forename: Tony
authors.initials: T
authors.lastname: Makhlouf
authors.forename: N Suzanne
authors.initials: NS
authors.lastname: Emil
authors.forename: Wilmer L
authors.initials: WL
authors.lastname: Sibbitt
authors.forename: Roderick A
authors.initials: RA
authors.lastname: Fields
authors.forename: Arthur D
authors.initials: AD
authors.lastname: Bankhurst
mesh_terms: D000305:Adrenal Cortex Hormones / Q000008:administration & dosage*; D000328:Adult; D002349:Carpal Tunnel Syndrome / Q000000981:diagnostic imaging / Q000191:economics* / Q000628:therapy*; D003362:Cost-Benefit Analysis; D005260:Female; D006801:Humans; D007270:Injections, Intra-Articular / Q000191:economics* / Q000379:methods; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000188:drug therapy / Q000209:etiology; D016896:Treatment Outcome; D014222:Triamcinolone Acetonide / Q000008:administration & dosage*; D014463:Ultrasonography
chemical_list: D000305:Adrenal Cortex Hormones; D014222:Triamcinolone Acetonide