Chien-Chou Pan1,2, Peter Simon1,3, Alejandro A Espinoza Orías1, Ryota Takatori1,4, Howard S An1, Gunnar B J Andersson1, Nozomu Inoue5. 1. Department of Orthopedic Surgery, Rush University Medical Center, 1611 W Harrison Street, Suite 201 Orthopedic Building, Chicago, IL, 60612, USA. 2. Department of Orthopedic Surgery, Taichung Veterans General Hospital, Taichung, Taiwan. 3. Phillip Spiegel Orthopaedic Research Laboratory, Foundation for Orthopaedic Research and Education, Tampa, FL, USA. 4. Department of Orthopedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan. 5. Department of Orthopedic Surgery, Rush University Medical Center, 1611 W Harrison Street, Suite 201 Orthopedic Building, Chicago, IL, 60612, USA. nozomu_inoue@rush.edu.
Abstract
OBJECTIVE: To report in vivo measurements of lumbar facet joint subchondral bone mineral density used in the description of facet joint loading patterns and to interrogate if low back pain is associated with changes in subchondral bone mineral density. MATERIALS AND METHODS: In vivo measurements of lumbar facet joint subchondral bone mineral density (L1/2 to L5/S1) in Hounsfield units were performed on 89 volunteers (56 controls and 33 with low back pain) by computed tomography osteoabsorptiometry at subchondral regions between 1.5 mm and 2.5 mm below the joint surface. The facet surface was divided into five topographic zones: cranial, lateral, caudal, medial, and central. RESULTS: We analyzed 1780 facet joint surfaces. Facets were denser (p < 0.0001) both in superior facets and in low back pain subjects (p < 0.0001). For the entire cohort, the facet center zone subchondral bone mineral density was higher (p < 0.0001) than that of the peripheral zones. The analyses indicate that subchondral bone mineral density is highest in patients with low back pain, the superior facets, and the center zone of the facets. CONCLUSIONS: Subchondral bone mineral density is thought to reflect cumulative, long-term distribution of stress acting on a joint. This work shows that higher subchondral bone mineral density values in the center zone indicate predominant stress transmission through the center of the facet joints. Finally, the greater subchondral bone mineral density in patients with low back pain may reflect both increased load bearing by the facets secondary to disc degeneration and misdistribution of loading within the joint.
OBJECTIVE: To report in vivo measurements of lumbar facet joint subchondral bone mineral density used in the description of facet joint loading patterns and to interrogate if low back pain is associated with changes in subchondral bone mineral density. MATERIALS AND METHODS: In vivo measurements of lumbar facet joint subchondral bone mineral density (L1/2 to L5/S1) in Hounsfield units were performed on 89 volunteers (56 controls and 33 with low back pain) by computed tomography osteoabsorptiometry at subchondral regions between 1.5 mm and 2.5 mm below the joint surface. The facet surface was divided into five topographic zones: cranial, lateral, caudal, medial, and central. RESULTS: We analyzed 1780 facet joint surfaces. Facets were denser (p < 0.0001) both in superior facets and in low back pain subjects (p < 0.0001). For the entire cohort, the facet center zone subchondral bone mineral density was higher (p < 0.0001) than that of the peripheral zones. The analyses indicate that subchondral bone mineral density is highest in patients with low back pain, the superior facets, and the center zone of the facets. CONCLUSIONS: Subchondral bone mineral density is thought to reflect cumulative, long-term distribution of stress acting on a joint. This work shows that higher subchondral bone mineral density values in the center zone indicate predominant stress transmission through the center of the facet joints. Finally, the greater subchondral bone mineral density in patients with low back pain may reflect both increased load bearing by the facets secondary to disc degeneration and misdistribution of loading within the joint.
Entities:
Keywords:
Low back pain; Lumbar facet joint; Subchondral bone density
Authors: C Y Duan; A A Espinoza Orías; S Shott; H S An; G B J Andersson; J Z Hu; H B Lu; N Inoue Journal: Osteoarthritis Cartilage Date: 2010-10-27 Impact factor: 6.576
Authors: Yoshihisa Otsuka; Howard S An; Ruth S Ochia; Gunnar B J Andersson; Alejandro A Espinoza Orías; Nozomu Inoue Journal: Spine (Phila Pa 1976) Date: 2010-04-15 Impact factor: 3.468
Authors: Peter Simon; Alejandro A Espinoza Orías; Gunnar B J Andersson; Howard S An; Nozomu Inoue Journal: Spine (Phila Pa 1976) Date: 2012-05-20 Impact factor: 3.468