Improving maternal health by reducing pregnancy-related low back pain

Low back pain is a leading cause of disability worldwide. It occurs in similar proportions in all cultures, and affects women more than men. This imbalance is accumulated by the high prevalence of pregnancy-related low back pain (PLBP). A woman’s body undergoes substantial changes during pregnancy, which are brought about by both hormonal and biomechanical effects. These changes lead to a variety of symptoms – including low back pain – that in some women cause severe discomfort. «Up to 86% of pregnant women develop PLBP, with 10% experiencing serious consequences that persist for several years postpartum», reports Dr. Nina Goossens, an AXA grantee at the Faculty of Rehabilitation Sciences of the Hasselt University in Belgium. «However, as for low back pain in general, the exact causes of PLBP remain largely unclear». To cast new light on the underlying mechanisms at play, Dr. Goossens and her team are investigating the interaction between biological, psychological and social contributors. In particular, they aim to study the role of proprioception, which refers to our ability to gauge the position, movement and equilibrium of our body in space. More specifically, the project works on the assumption that changes in proprioception related to postural control (the maintenance of our body equilibrium), body perception, and fear of movement contribute to the development of persistent PLBP during pregnancy and postpartum. The overall objective is to identify predictive factors of PLBP, which can be used to create or improve preventative and curative strategies.

To explain the rationale behind her innovative focus, the lead investigator explains that «alterations in standing postural control have been observed frequently in low back pain independent of pregnancy. Interestingly, women with persistent PLBP postpartum more often report disturbances in body perception and fear of movement, factors previously linked to persistent low back pain. However, alterations in proprioception, a primary sense for postural control and body perception, and the association with PLBP have not been investigated yet during pregnancy and postpartum ». Going into more details about what proprioception is, and what it does, she continues: «To maintain optimal postural control, proprioceptive inputs from different body parts are necessary. These proprioceptors signal changes in body position and movement and are processed centrally, together with visual and vestibular signals, to create corrective motor actions. Depending on the postural conditions, the brain will identify and increase its reliance on the most relevant proprioceptive inputs, while reducing the use of less reliable inputs. However, multiple studies from our research group have demonstrated that individuals with low back pain, independent of pregnancy, show an impaired use of proprioception during postural control. More specifically, they predominantly rely on ankle proprioception, probably to compensate for the proprioceptive impairments observed at the lower back in this population. Interestingly, this dominant reliance on ankle proprioception is a potential risk factor for the development and recurrence of low back pain. However, again, no studies have investigated whether women show an impaired use of proprioception during postural control throughout and after pregnancy, nor determined whether this is related to the development and persistence of PLBP ».

Examining the dynamic interactions between biological, psychological and social factors

To fill this gap, Dr. Nina Goossens and her team will conduct a longitudinal study, meaning that they will follow a cohort of women over a prolonged period of time, in this case, from the first trimester of pregnancy until six months postpartum. During that period, and at five different time points, the participants will fill out questionnaires and go through physiotherapeutic assessments. The objective will be to collect data on biological variables such as postural sway or proprioceptive use during standing, but also on psychological and social factors. Indeed, «contemporary evidence indicates that low back pain, both related to and independent of pregnancy, is the result of a dynamic interaction between biological, psychological and social factors. Previous research has demonstrated that psychological traits, such as kinesiophobia (fear of movement), pain catastrophizing and fear-avoidance beliefs, have a negative impact on PLBP». The results will then be statistically analyzed to identify predictive factors. In simpler terms, «each time they collect data on the participating women, they will be divided into the ones with pain, and the ones without pain. Then, we’ll look for relevant correlations with the collected biological and psychological variables, to shed light on which factors predict the development of low back pain ». «My hope is that, by identifying predictive factors for PLBP, we will be able to make a real impact on maternal health. My PhD research was rather fundamental, investigating neural correlates of non-specific low back pain. With the present project, I want to get back to something more clinical, something that matches better with my degree in physical therapy. »

Because of the pain and disability it causes to women, PLBP has considerable socio-economic consequences. It leads to high healthcare costs, work absenteeism, and reduced long-term employability. Considering that its global prevalence has drastically increased over the past decades, investigative research into the underlying factors is urgently needed. In that sense, Dr. Nina Goossens’ innovative approach, combining the study of biological, psychological and social factors, promises to provide new comprehensive insight into the variables that potentially play a decisive role. By focusing on PLBP, and not on low back pain in general, the researcher also addresses one of today’s biggest medical challenges: the specific health needs of women. «Many women are resigned to endure low back pain, because they think it is a natural part of pregnancy. It’s not, and there are strategies that can be put into place to avoid recurrence and to ease the pain», the researcher insists.