MRI evaluation of spontaneous intervertebral disc degeneration in the alpaca cervical spine

Abstract

Animal models have historically provided an appropriate benchmark for understanding human pathology, treatment, and healing, but few animals are known to naturally develop intervertebral disc degeneration. The study of degenerative disc disease and its treatment would greatly benefit from a more comprehensive, and comparable animal model. Alpacas have recently been presented as a potential large animal model of intervertebral disc degeneration due to similarities in spinal posture, disc size, biomechanical flexibility, and natural disc pathology. This research further investigated alpacas by determining the prevalence of intervertebral disc degeneration among an aging alpaca population. Twenty healthy female alpacas comprised two age subgroups (5 young: 2-6 years; and 15 older: 10þ years) and were rated according to the Pfirrmann-grade for degeneration of the cervical intervertebral discs. Incidence rates of degeneration showed strong correlations with age and spinal level: younger alpacas were nearly immune to developing disc degeneration, and in older animals, disc degeneration had an increased incidence rate and severity at lower cervical levels. Advanced disc degeneration was present in at least one of the cervical intervertebral discs of 47% of the older alpacas, and it was most common at the two lowest cervical intervertebral discs. The prevalence of intervertebral disc degeneration encourages further investigation and application of the lower cervical spine of alpacas and similar camelids as a large animal model of intervertebral disc degeneration.

Molecular mechanisms of biological aging in intervertebral discs

“…Vicugna pacos Young (2-6 years) and older (>10 years) alpaca underwent MRI evaluation to detect cervical spine degeneration No cervical disc degeneration in young alpacas. Increased disc degeneration incidence and severity at lower cervical levels in older alpacas 235 Rhesus Macaques Macaca mulatta (Macaques monkeys) Longitudinal study of macques 11-32 years of age to assess disc space narrowing (DSN) by radiography Age-associated disc space narrowing, osteophytosis, increased disc tissue stiffness 236 Genetic models: M, mutation; TG, transgenic; ARM, autosomal recessive mutation; TM, truncation mutation; N/A, not applicable.…”

Age‐related spontaneous lumbar intervertebral disc degeneration in a mouse model

“…The pathogenesis of intervertebral disc (IVD) degeneration is unclear, but it is a major cause of several spinal diseases and has a great impact on quality of life . A large percentage of the aging human population is afflicted with seemingly irreversible IVD degeneration: Approximately 40% of people less than 30 years old and upwards of 90% of people 55 years old or older are afflicted with moderate‐to‐severe levels of IVD degeneration in their lumbar spine . Fundamental treatment is required; however, treatment is largely limited to symptomatic relief with non‐steroidal anti‐inflammatories and surgical treatment, because the mechanisms of the degeneration are still not completely understood …”

“…A general understanding of the causes of IVD degeneration is limited because of the difficult nature of obtaining and testing appropriate, live human material . A likely step in accelerating research and forging breakthroughs in IVD degeneration and lower back pain may rely on the ability to identify more accurate animal models . Animal models have historically provided an appropriate benchmark for understanding human IVD biology .…”

“…A likely step in accelerating research and forging breakthroughs in IVD degeneration and lower back pain may rely on the ability to identify more accurate animal models . Animal models have historically provided an appropriate benchmark for understanding human IVD biology . Among several animal models, the mouse IVD needle puncture model has been developed .…”

Identification of key genes associated with the effect of osmotic stimuli on intervertebral discs using microarray analysis

“…The etiology of lower back pain is unclear, but in 40% of cases it is associated with IVD degeneration (4). It is reported that ~40% of individuals <30 years of age, and >90% of individuals >55 years, exhibit moderate-to-severe levels of IVD degeneration (5,6). It is estimated that the costs associated with lumbar disc and lower back disorders exceed $100 billion/year in the USA (7).…”