Research finds a lack of strong association between pelvic tilts and pain. (Photo by Nick Ng)
A 2020 study of non-surgical treatments for the anterior pelvic tilt reported “no evidence supports excessive anterior pelvic tilt as an isolated clinical disorder or pathology.” and having a cutoff point in determining what an excessive pelvic tilt means can be misleading because “sagittal balance can be individually regulated to maintain a proper posture.”
In other words, each person has their own way to move and adapt, and no single range of anterior pelvic tilt or posture can fit into everyone’s movement patterns.
“Looking for pelvic tilts is subjective, not to mention that postural adjustments are made moment to moment. The accuracy of assessing a tilt is not reliable nor is it functional,” Dr. Susie Gronski said in an email interview, who is a pelvic pain physical therapist practicing in Asheville, North Carolina. “There is an overwhelming amount of evidence to sway my bias in the direction that tissue-based issues are not the sole factor in someone’s pain experience. Of course, peripheral nociception can be one factor for tissue sensitivity, but [it is] not the only factor at play.”
Gronski also said that pain “is a conscious experience that motivates us to take action, grabs our attention.”
“Nociception involves peripheral sensory neurons picking up on changes in the tissue environment and sending these messages to the spinal cord and brain,” Gronski said. “The brain filters the information and whether someone will experience pain or not is highly dependent on context, their beliefs and thoughts about pain, and even subconscious factors that we have yet to discover.”
Evidence on posture assessments
Research has found some factors that can cause clinicians to make false positive findings in pelvic tilt assessments. A 2005 study of 160 pain-free subjects from a medical center in Lyon, France, found a wide range of pelvic and spinal postural variations.
For example, the S1 joint had a variation between 20 to 65 degrees at the vertebral endplate at the horizontal axis, and lumbar lordosis varied between 41 to 82 degrees.
An earlier study in 1982 also found similar variations among 100 asymptomatic samples. The researchers wrote that it is “unreasonable to speak of normal kyphosis and lordotic curves” because their data found a wide range of curvatures. “The average values are only indicative and not normative. The extreme values show the morphologic latitude of the human species.”
Even the landmarks that clinicians were taught to palpate in a pelvic tilt assessment—anterior superior iliac spine (ASIS) and posterior superior iliac spine (PSIS)— vary in position and angle.
A 2008 study compared the angles of the ASIS and PSIS of 30 pelvises and found a wide variation (0 to 23 degrees). The researchers also found variations in the angles from the ischial tuberosity to the iliac crest on both sides of the pelvis.
They warned, “The ASIS-PSIS angle should not be used in isolation to assess pelvic orientation. Additional factors should also be taken into consideration, such as the depth of the lumbar lordosis and the hip joint angle in standing with neutral knee joint alignment.” Any type of pelvic tilt assessment should be “viewed with caution.”
However, a previous larger study of 323 radiographs of the pelvis found a similar pattern of asymmetry between the left and right sides of the pelvis where the researchers measured the difference of heights from the iliac crests to the acetabuli. They reported “a much lower prevalence and a smaller range of pelvic asymmetries” compared to similar studies.
The primary difference is that this study included scans of the pelvis and abdominal region, not just from scans of patients with back pain, and it did not included ASIS-PSIS angles.
“To say that any one body needs to be in any one posture or position is unrealistic, fear-mongering, and steals a person’s self-efficacy by sending messages of fragility instead of capability.” ~ Dr. Susie Gronski
Is pelvic tilt assessment a waste of time?
Whether pelvic tilt assessments are worth your time is debatable because there is no definitive agreement among healthcare professionals. However, given that pain is a multi-factorial subjective experience and the current scientific literature find a weak correlation of posture and pain, clinicians should not narrow the cause down to one factor.
Gronski asked three questions to clinicians who do use pelvic tilt assessment:
- Why are you assessing?
- What valuable information does it provide?
- How does it translate into function or helping that person move better?
For example, she said physical therapists use certain hands-on tests to see if there is pain or dysfunction in a patient’s sacroiliac joint. Although such tests are able to differentiate pain between the lower back and sacroiliac joint, they do not tell clinicians or patients why there is pain.
“These tests also tell us nothing about the amount of movement in the sacroiliac joint,” Gronski said. “In fact, the reliability of feeling a few degrees of motion in a structure that is very stable and support is questionable. We’re talking about millimeters of movement.”
Gronski added that pelvic tilt assessments “rarely translate to any real changes in someone’s ability to function in life, do what they love, or eliminate their pain.”
“To say that any one body needs to be in any one posture or position is unrealistic, fear-mongering, and steals a person’s self-efficacy by sending messages of fragility instead of capability,” she said.
Gronski said perhaps a better solution would be to encourage patients to tell their story about their pain. This allows both the clinician and the patient to explore other possibilities of why the pain exists and let the clinician to have a better insight of the patient’s problem beyond their biology.
“It’s important to approach pain care that is person-centered rather than symptom centered,” Gronski said.
Nick Ng is the editor of Massage & Fitness Magazine and the managing editor for My Neighborhood News Network.
An alumni from San Diego State University with a bachelor’s degree in graphic communications, Nick had completed his massage therapy training at International Professional School of Bodywork in San Diego in 2014. In 2021, he earned an associate’s degree in journalism at Palomar College.
When he gets a chance, he enjoys weightlifting at the gym, salsa dancing, and exploring new areas in the Puget Sound area in Washington state.
