Ankylosing spondylitis (AS) is a condition which literally means “stiffening inflammation of the spine”. It’s a progressive arthritis that affects joints and organs in the body, from the eyes to the ankles or hips to the heart.[i]
For clinicians, AS is notable for its association with temporomandibular joint disorder (TMD). TMD affects mastication, speech and ultimately quality of life, if left untreated. By boosting understanding of AS, clinicians can better identify and support at-risk patients.
Inflammation of the spine is commonly reported as back pain and stiffness, with pain and swelling also found in other parts of the body. Extreme tiredness is another leading symptom.
The development of these symptoms is gradual; some over several months and others over several years. As they can come and go, patients may think that the problem has been solved.[ii] However, it can also get progressively worse. Among chronic cases, patients can become severely disabled as their spinal bones fuse into a fixed position. This increases the risk of osteoporosis and spinal fractures.ii
The cause of AS is a mystery. One source of scientific interest is the gene variant HLA-B27, found in over 80% of patients with AS. Among the general population, the gene is found in an estimated 8% of people. As such, inherited factors can increase the risk of developing AS, making it harder to prevent, but potentially easier to identify at-risk patients whose parents experience it.[iii]
Furthermore, AS disproportionately affects males. Young men aged 17-35, in particular, are nine times more likely to develop it than their female counterparts. For women, AS symptoms often first appear during pregnancy.i
Studies have found a high prevalence of the disease in patients with TMD. Research suggests an AS prevalence of 59% in TMD patients.[iv] Supporting patients with AS can therefore better reduce TMD symptoms for optimal care outcomes.
Because of an intra-articular disc in the temporomandibular joint (TMJ), ankylosis is rare in the TMJ.iv However, the wider impact of AS increases the risk of TMD. This includes breakdown of articular surfaces and changes in posture. Research has already found a strong correlation between poor posture and TMD, with shifts in a patient’s centre of gravity caused by the head moving forwards.[v] This is worsened by AS, a well-established cause of chronic back pain.[vi] Resulting postural changes place extra strain on the joints.
Treating AS can be difficult. Solutions to relieve symptoms include:
To improve posture, cervical pillows and sleeping on the back can help at night. Everyday tasks should also be completed in an upright, rather than hunched, position.[vii]
To support patients with TMD, recommend the OraStretchâ Press Rehab System from Total TMJ. A user-operated device ideal for home rehabilitation, it stretches the orofacial tissues to restore strength and function to the TMJ. Reduce TMD-induced pain and swelling with the OraStretchâ Press today.
Whilst the prevalence of AS is low, patients affected by it may experience intense pain, physical disability and an overall negative quality of life. By raising awareness of the condition, clinicians are better equipped to help those at risk.
For more details about Total TMJ and the products available, please email info@totaltmj.co.uk
[i] Umms.org. (2026). Ankylosing Spondylitis. [online] Available at: https://www.umms.org/ummc/health-services/orthopedics/services/spine/patient-guides/ankylosing-spondylitis# [Accessed 6 Jan. 2026].
[ii] NHS (2019). Overview – Ankylosing spondylitis. [online] NHS. Available at: https://www.nhs.uk/conditions/Ankylosing-spondylitis/.
[iii] NHS (2018). Ankylosing spondylitis – Causes. [online] nhs.uk. Available at: https://www.nhs.uk/conditions/ankylosing-spondylitis/causes/.
[iv] Rebeca Monteiro Souza, Tavares, E., David Cordeiro Sousa, Marcelo Magalhães Sales, Oliveira, S., Mariano, M., Eliezer Rushansky, Ana and Emanuel Araújo Silva (2021). Prevalence of Temporomandibular Joint Disorders in Patients with Ankylosing Spondylitis: A Cross-Sectional Study. Clinical, Cosmetic and Investigational Dentistry, Volume 13, pp.469–478. doi:https://doi.org/10.2147/ccide.s320537.
[v] Minervini, G., Franco, R., Maria Maddalena Marrapodi, Crimi, S., Almir Badnjević, Cervino, G., Bianchi, A. and Cicciù, M. (2023). Correlation between Temporomandibular Disorders (TMD) and Posture Evaluated trough the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD): A Systematic Review with Meta-Analysis. Journal of Clinical Medicine, 12(7), pp.2652–2652. doi:https://doi.org/10.3390/jcm12072652.
[vi] de Holanda, G.A., de Holanda, T.A., Boscato, N. and Casarin, M. (2022). Temporomandibular joint involvement in individuals with ankylosing spondylitis: A scoping review. Archives of Oral Biology, [online] 146, p.105609. doi:https://doi.org/10.1016/j.archoralbio.2022.105609.
[vii] Iavarone, K. (2023). What’s the Difference Between Spondylitis and Spondylosis? [online] Healthline. Available at: https://www.healthline.com/health/ankylosing-spondylitis/spondylitis-vs-spondylosis#outlook [Accessed 6 Jan. 2026].