Aaron Fields, PhD

Associate Professor
Orthopaedic Surgery
+1 415 476-0960

Aaron Fields, Ph.D., is an Associate Professor of Orthopaedic Surgery at UCSF. He received his Bachelor of Science degree in Mechanical Engineering from the University of Denver in 2005, and his Masters and Doctoral degrees, also in Mechanical Engineering, from the University of California, Berkeley in 2008 and 2010. His undergraduate research was on the use of probabilistic techniques to evaluate knee implant performance, and both of his graduate thesis projects focused on discovering the mechanisms of vertebral fragility using high-resolution computational models. Aaron was appointed to a faculty position at UCSF after completing his post-doctoral fellowship in Orthopaedic Surgery in 2015. His background includes extensive research in experimental and computational biomechanics. Aaron is an active member of the Orthopaedic Research Society and the International Society for the Study of the Lumbar Spine.

Aaron currently directs the Orthopaedic Biomechanics and Biotransport Laboratory at UCSF. The lab's broad research interests are related to structure-function relationships in musculoskeletal tissues, with a particular focus on the mechanisms of nutrient transport in bone and cartilage and harnessing nutrient transport for tissue repair and regeneration. The lab combines engineering and biology approaches for (1) understanding the effects of aging and disease on structure-transport relationships and (2) developing translatable diagnostic and therapeutic strategies. An overall theme of this research is the use of advanced experimental and computational tools to measure how tissue constituents at the nano- and microscales impact whole-organ behavior.

Interests: orthopaedic biomechanics, spine, intervertebral disc degeneration, bone fragility, finite element analysis, osteoporosis, micro-CT, image analysis, materials testing, big data

Publications: 

[Evidence-based interventions to treat chronic low back pain: treatment selection for a personalized medicine approach : German version].

Schmerz (Berlin, Germany)

Mauck MC, Aylward AF, Barton CE, Birckhead B, Carey T, Dalton DM, Fields AJ, Fritz J, Hassett AL, Hoffmeyer A, Jones SB, McLean SA, Mehling WE, O'Neill CW, Schneider MJ, Williams DA, Zheng P, Wasan AD

Low back pain patients with Modic type 1 changes exhibit distinct bacterial and non-bacterial subtypes.

Osteoarthritis and cartilage open

Heggli I, Mengis T, Laux CJ, Opitz L, Herger N, Menghini D, Schuepbach R, Farshad-Amacker NA, Brunner F, Fields AJ, Farshad M, Distler O, Dudli S

Type 2 diabetes impairs annulus fibrosus fiber deformation and rotation under disc compression in the University of California Davis type 2 diabetes mellitus (UCD-T2DM) rat model.

PNAS nexus

Rosenberg JL, Schaible E, Bostrom A, Lazar AA, Graham JL, Stanhope KL, Ritchie RO, Alliston TN, Lotz JC, Havel PJ, Acevedo C, Fields AJ

Magnetic resonance imaging of the lumbar spine-recommendations for acquisition and image evaluation from the BACPAC Spine Imaging Working Group.

Pain medicine (Malden, Mass.)

Sollmann N, Fields AJ, O'Neill C, Nardo L, Majumdar S, Chin CT, Tosun D, Han M, Vu AT, Ozhinsky E, Shah LM, Harris RE, Lobo R, Anderst W, Herzog R, Psioda MA, Standaert CJ, Price RT, Lotz JC, Link TM, Krug R

Protocol for Biospecimen Collection and Analysis within the BACPAC Research Program.

Pain medicine (Malden, Mass.)

Fields AJ, Dudli S, Schrepf A, Kim A, Pham B, Gallego E, Mendoza S, Meropol SB, Darwin J, Sowa G, Vo NV

The BACPAC Research Program Data Harmonization: Rationale for Data Elements and Standards.

Pain medicine (Malden, Mass.)

Batorsky A, Bowden AE, Darwin J, Fields AJ, Greco CM, Harris RE, Hue TF, Kakyomya J, Mehling W, O'Neill C, Patterson CG, Piva SR, Sollmann N, Toups V, Wasan AD, Wasserman R, Williams DA, Vo NV, Psioda MA, McCumber M

The Back Pain Consortium (BACPAC) Research Program: Structure, Research Priorities, and Methods.

Pain medicine (Malden, Mass.)

Mauck MC, Lotz J, Psioda MA, Carey TS, Clauw DJ, Majumdar S, Marras WS, Vo N, Aylward A, Hoffmeyer A, Zheng P, Ivanova A, McCumber M, Carson C, Anstrom KJ, Bowden AE, Dalton D, Derr L, Dufour J, Fields AJ, Fritz J, Hassett AL, Harte SE, Hue TF, Krug R, Loggia ML, Mageswaran P, McLean SA, Mitchell UH, O'Neill C, Pedoia V, Quirk DA, Rhon DI, Rieke V, Shah L, Sowa G, Spiegel B, Wasan AD, Wey HM, LaVange L

Bullying, harassment, and discrimination of musculoskeletal researchers and the impact of the COVID-19 pandemic: an international study.

European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society

Martin JT, Asimakopoulos D, Hornung AL, Toro SJ, Le Maitre CL, Chahine NO, Fields AJ, Gawri R, Giers MB, Smith LJ, Tang SY, Zehra U, Haglund L, Samartzis D

Deep-learning-based biomarker of spinal cartilage endplate health using ultra-short echo time magnetic resonance imaging.

Quantitative imaging in medicine and surgery

Bonnheim NB, Wang L, Lazar AA, Chachad R, Zhou J, Guo X, O'Neill C, Castellanos J, Du J, Jang H, Krug R, Fields AJ

Intradiscal treatment of the cartilage endplate for improving solute transport and disc nutrition.

Frontiers in bioengineering and biotechnology

Habib M, Hussien S, Jeon O, Lotz JC, Wu PI, Alsberg E, Fields AJ

ISSLS Prize in Bioengineering Science 2023: Age- and sex-related differences in lumbar intervertebral disc degeneration between patients with chronic low back pain and asymptomatic controls.

European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society

Bonnheim NB, Lazar AA, Kumar A, Akkaya Z, Zhou J, Guo X, O'Neill C, Link TM, Lotz JC, Krug R, Fields AJ

UTE-MRI for Spinal Applications.

MRI of Short and Ultrashort-T_2 Tissues

Noah B. Bonnheim, Misung Han, Aaron J. Fields, Cynthia Chin, Roland Krug

Evidence-based interventions to treat chronic low back pain: treatment selection for a personalized medicine approach.

Pain reports

Mauck MC, Aylward AF, Barton CE, Birckhead B, Carey T, Dalton DM, Fields AJ, Fritz J, Hassett AL, Hoffmeyer A, Jones SB, McLean SA, Mehling WE, O'Neill CW, Schneider MJ, Williams DA, Zheng P, Wasan AD

Influence of patient-specific factors when comparing multifidus fat infiltration between chronic low back pain patients and asymptomatic controls.

JOR spine

Ballatori AM, Shahrestani S, Nyayapati P, Agarwal V, Krug R, Han M, Fields AJ, O'Neill C, Demir-Deviren S, Lotz JC, Bailey JF

Spatial distribution of fat infiltration within the paraspinal muscles: implications for chronic low back pain.

European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society

Khattab K, Dziesinski LK, Crawford R, Ballatori A, Nyayapati P, Krug R, Fields A, O'Neill CW, Lotz JC, Bailey JF

The contributions of cartilage endplate composition and vertebral bone marrow fat to intervertebral disc degeneration in patients with chronic low back pain.

European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society

Bonnheim NB, Wang L, Lazar AA, Zhou J, Chachad R, Sollmann N, Guo X, Iriondo C, O'Neill C, Lotz JC, Link TM, Krug R, Fields AJ

Using hierarchical unsupervised learning to integrate and reduce multi-level and multi-paraspinal muscle MRI data in relation to low back pain.

European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society

Torres-Espin A, Keller A, Johnson GTA, Fields AJ, Krug R, Ferguson AR, Hargens AR, O'Neill CW, Lotz JC, Bailey JF

Paraspinal Muscle in Chronic Low Back Pain: Comparison Between Standard Parameters and Chemical Shift Encoding-Based Water-Fat MRI.

Journal of magnetic resonance imaging : JMRI

Sollmann N, Bonnheim NB, Joseph GB, Chachad R, Zhou J, Akkaya Z, Pirmoazen AM, Bailey JF, Guo X, Lazar AA, Link TM, Fields AJ, Krug R

Non-enzymatic glycation of annulus fibrosus alters tissue-level failure mechanics in tension.

Journal of the mechanical behavior of biomedical materials

Werbner B, Lee M, Lee A, Yang L, Habib M, Fields AJ, O'Connell GD

Development of a standardized histopathology scoring system for human intervertebral disc degeneration: an Orthopaedic Research Society Spine Section Initiative.

JOR spine

Le Maitre CL, Dahia CL, Giers M, Illien-Junger S, Cicione C, Samartzis D, Vadala G, Fields A, Lotz J

Measurement of vertebral endplate bone marrow lesion (Modic change) composition with water-fat MRI and relationship to patient-reported outcome measures.

European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society

Fields AJ, Ballatori A, Han M, Bailey JF, McCormick ZL, O'Neill CW, Demir-Deviren S, Krug R, Lotz JC

Automatic Vertebral Body Segmentation Based on Deep Learning of Dixon Images for Bone Marrow Fat Fraction Quantification.

Frontiers in endocrinology

Zhou J, Damasceno PF, Chachad R, Cheung JR, Ballatori A, Lotz JC, Lazar AA, Link TM, Fields AJ, Krug R

Evaluation of human cartilage endplate composition using MRI: Spatial variation, association with adjacent disc degeneration, and in vivo repeatability.

Journal of orthopaedic research : official publication of the Orthopaedic Research Society

Wang L, Han M, Wong J, Zheng P, Lazar AA, Krug R, Fields AJ

Serum Biomarkers for Connective Tissue and Basement Membrane Remodeling are Associated with Vertebral Endplate Bone Marrow Lesions as Seen on MRI (Modic Changes).

International journal of molecular sciences

Dudli S, Ballatori A, Bay-Jensen AC, McCormick ZL, O'Neill CW, Demir-Deviren S, Krug R, Heggli I, Juengel A, Karppinen J, Brunner F, Farshad M, Distler O, Lotz JC, Fields AJ

Osteocyte dysfunction promotes osteoarthritis through MMP13-dependent suppression of subchondral bone homeostasis.

Bone research

Mazur CM, Woo JJ, Yee CS, Fields AJ, Acevedo C, Bailey KN, Kaya S, Fowler TW, Lotz JC, Dang A, Kuo AC, Vail TP, Alliston T

Measuring and reporting of vertebral endplate bone marrow lesions as seen on MRI (Modic changes): recommendations from the ISSLS Degenerative Spinal Phenotypes Group.

European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society

Fields AJ, Battié MC, Herzog RJ, Jarvik JG, Krug R, Link TM, Lotz JC, O'Neill CW, Sharma A, ISSLS Degenerative Spinal Phenotypes Group

The Relationship Between Endplate Pathology and Patient-reported Symptoms for Chronic Low Back Pain Depends on Lumbar Paraspinal Muscle Quality.

Spine

Bailey JF, Fields AJ, Ballatori A, Cohen D, Jain D, Coughlin D, O'Neill C, McCormick Z, Han M, Krug R, Demir-Deviren S, Lotz JC

Associations between vertebral body fat fraction and intervertebral disc biochemical composition as assessed by quantitative MRI.

Journal of magnetic resonance imaging : JMRI

Krug R, Joseph GB, Han M, Fields A, Cheung J, Mundada M, Bailey J, Rochette A, Ballatori A, McCulloch CE, McCormick Z, O'Neill C, Link TM, Lotz J

Estrogen signaling in arcuate Kiss1 neurons suppresses a sex-dependent female circuit promoting dense strong bones.

Nature communications

Herber CB, Krause WC, Wang L, Bayrer JR, Li A, Schmitz M, Fields A, Ford B, Zhang Z, Reid MS, Nomura DK, Nissenson RA, Correa SM, Ingraham HA

Effects of dynamic loading on solute transport through the human cartilage endplate.

Journal of biomechanics

Sampson SL, Sylvia M, Fields AJ

Contribution of the endplates to disc degeneration.

Current molecular biology reports

Fields AJ, Ballatori A, Liebenberg EC, Lotz JC

Tidemark Avulsions are a Predominant Form of Endplate Irregularity.

Spine

Berg-Johansen B, Jain D, Liebenberg EC, Fields AJ, Link TM, O'Neill CW, Lotz JC

FGF and TGFß signaling link form and function during jaw development and evolution.

Developmental biology

Woronowicz KC, Gline SE, Herfat ST, Fields AJ, Schneider RA

Cartilage Endplate Thickness Variation Measured by Ultrashort Echo-Time MRI Is Associated With Adjacent Disc Degeneration.

Spine

Berg-Johansen B, Han M, Fields AJ, Liebenberg EC, Lim BJ, Larson PE, Gunduz-Demir C, Kazakia GJ, Krug R, Lotz JC

Publication trends in spine research from 2007 to 2016: Comparison of the Orthopaedic Research Society Spine Section and the International Society for the Study of the Lumbar Spine.

JOR spine

Martin JT, Gullbrand SE, Fields AJ, Purmessur D, Diwan AD, Oxland TR, Chiba K, Guilak F, Hoyland JA, Iatridis JC

Larger vertebral endplate concavities cause higher failure load and work at failure under high-rate impact loading of rabbit spinal explants.

Journal of the mechanical behavior of biomedical materials

Dudli S, Enns-Bray W, Pauchard Y, Römmeler A, Fields AJ, Ferguson SJ, Helgason B

Contributions of Material Properties and Structure to Increased Bone Fragility for a Given Bone Mass in the UCD-T2DM Rat Model of Type 2 Diabetes.

Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research

Acevedo C, Sylvia M, Schaible E, Graham JL, Stanhope KL, Metz LN, Gludovatz B, Schwartz AV, Ritchie RO, Alliston TN, Havel PJ, Fields AJ

Structure-function relationships at the human spinal disc-vertebra interface.

Journal of orthopaedic research : official publication of the Orthopaedic Research Society

Berg-Johansen B, Fields AJ, Liebenberg EC, Li A, Lotz JC

Role of Osteoblast Gi Signaling in Age-Related Bone Loss in Female Mice.

Endocrinology

Millard SM, Wang L, Wattanachanya L, O'Carroll D, Fields AJ, Pang J, Kazakia G, Lotz JC, Nissenson RA

Glucocorticoid suppression of osteocyte perilacunar remodeling is associated with subchondral bone degeneration in osteonecrosis.

Scientific reports

Fowler TW, Acevedo C, Mazur CM, Hall-Glenn F, Fields AJ, Bale HA, Ritchie RO, Lotz JC, Vail TP, Alliston T

Pathobiology of Modic changes.

European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society

Dudli S, Fields AJ, Samartzis D, Karppinen J, Lotz JC

Alterations in intervertebral disc composition, matrix homeostasis and biomechanical behavior in the UCD-T2DM rat model of type 2 diabetes.

Journal of orthopaedic research : official publication of the Orthopaedic Research Society

Fields AJ, Berg-Johansen B, Metz LN, Miller S, La B, Liebenberg EC, Coughlin DG, Graham JL, Stanhope KL, Havel PJ, Lotz JC

Trabecular plates and rods determine elastic modulus and yield strength of human trabecular bone.

Bone

Wang J, Zhou B, Liu XS, Fields AJ, Sanyal A, Shi X, Adams M, Keaveny TM, Guo XE

Comparison of vertebral and intervertebral disc lesions in aging humans and rhesus monkeys.

Osteoarthritis and Cartilage

Bailey JF, Fields AJ, Liebenberg E, Mattison JA, Lotz JC, Kramer PA

Structural parameters determining the strength of the porcine vertebral body affected by tumours.

Computer methods in biomechanics and biomedical engineering

Sahli F, Cuellar J, Pérez A, Fields AJ, Campos M, Ramos-Grez J

Influence of biochemical composition on endplate cartilage tensile properties in the human lumbar spine.

Journal of orthopaedic research : official publication of the Orthopaedic Research Society

Fields AJ, Rodriguez D, Gary KN, Liebenberg EC, Lotz JC

Innervation of pathologies in the lumbar vertebral end plate and intervertebral disc.

The spine journal : official journal of the North American Spine Society

Fields AJ, Liebenberg EC, Lotz JC

The role of the vertebral end plate in low back pain.

Global spine journal

Lotz JC, Fields AJ, Liebenberg EC

Vertebral fragility and structural redundancy.

Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research

Fields AJ, Nawathe S, Eswaran SK, Jekir MG, Adams MF, Papadopoulos P, Keaveny TM

Micromechanics of the human vertebral body for forward flexion.

Journal of biomechanics

Yang H, Nawathe S, Fields AJ, Keaveny TM

Trabecular architecture and vertebral fragility in osteoporosis.

Current osteoporosis reports

Fields AJ, Keaveny TM

Influence of vertical trabeculae on the compressive strength of the human vertebra.

Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research

Fields AJ, Lee GL, Liu XS, Jekir MG, Guo XE, Keaveny TM

Mechanisms of initial endplate failure in the human vertebral body.

Journal of biomechanics

Fields AJ, Lee GL, Keaveny TM

Role of trabecular microarchitecture in whole-vertebral body biomechanical behavior.

Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research

Fields AJ, Eswaran SK, Jekir MG, Keaveny TM

Multi-scale modeling of the human vertebral body: comparison of micro-CT based high-resolution and continuum-level models.

Pacific Symposium on Biocomputing. Pacific Symposium on Biocomputing

Eswaran SK, Fields AJ, Nagarathnam P, Keaveny TM

Effects of knee simulator loading and alignment variability on predicted implant mechanics: a probabilistic study.

Journal of orthopaedic research : official publication of the Orthopaedic Research Society

Laz PJ, Pal S, Fields A, Petrella AJ, Rullkoetter PJ