The Different Curves of the Spine, and What They Mean

Today we are going to focus on the back, in general terms, and then narrow down to what this means for women.

All backs and spines, whether they’re in a male or female or other body, will ideally make an “S” shape.

• Cervical (neck) curve – curves slightly forward (lordosis)
• Thoracic (mid-back) curve – curves slightly backward (kyphosis)
• Lumbar (low back) curve – curves forward again (lordosis)

The “S” shape acts like a spring, absorbs the impact of movement, and allows your spine to carry the weight of your body in a balanced way(1). When these curves are in balanced, your muscles (especially the pelvic floor) aren’t overworked, your joints wear evenly, and your nervous system can function at full capacity.

There are 3 main issues that we see in women:

1. Upper Cross Syndrome – this is where the lordosis and kyphosis of the neck and upper back curve past the body’s centreline, putting extra pressure on the neck muscles. As a syndrome, there are a variety of things working in concert to allow this posture; mainly, a tight chest complex and a long posterior neck and shoulder complex(2).

   

2. Lower Cross Syndrome (Type A)- This occurs when the lumbar lordosis increases to a point where there’s little to no support along the torso. Again, a variety of issues contribute to this imbalance; mainly a tight/short lower back, and a long abdominal wall(3).

   

3. Flat Lower Back (also known as Type B Lower Cross Syndrome) – This is basically the opposite of Type A, where the lower back is long and flat, and the lower chest is short and tight(4).

   

Women are more likely to develop Upper Cross Syndrome than men(5). Things that increase risk are use of a handheld device for reading, working, and travelling, sleeping in the fetal position, and sitting in an unsupported chair(6). However, these things are not unique to women, and do not fully explain why they’re more likely to develop upper cross syndrome.

Using my experience, i can theorize that women already have a greater thoracic curve than men because of their rounder rib cages. This primes us for upper cross syndrome, but our environment pulls the trigger. Looking after a baby, breastfeeding, and working at  a desk all ask the upper body to curl forwards. When we are already “primed” that way, gravity does the rest.

Women are also more at risk of developing lower cross syndrome (7). Some studies have shown that a sedentary lifestyle, lack of exercise, previous injuries or surgeries, and genetic factors play into why this is (8). Again, these factors are not unique to women and do not fully explain why they are more affected.

My thinking and experience goes as follows:

Women generally have a longer lumbar area; the space between her bottom rib and the top of her pelvis is larger than a man the same size. This anatomical difference allows the female body to accommodate a pregnancy, but is also means her lumbar spine has less bony support.

Oestrogen also impacts our ligaments and tendons, making them more pliable than men. On the one hand, this means our pelvis’s have the capacity to flex and pass a baby through the birth canal, and it means we have greater mobility generally. On the other hand it also means we have less stability; we have to exert more effort maintaining our posture and balance under these conditions.

In Type A Lower Cross Syndrome, pregnancy further lengthens the abdominal wall, which means the back muscles will often tighten. Once the baby is birthed, it takes time for the abdominal wall to return to full integrity, and in that time a woman is often performing the lions share of caring for the baby. Without any rehabilitation or guidance, her abdominal wall may just stay long, and her lower back may just stay tight forever.

Type B Lower Cross Syndrome is characterised by the flat lower back. Sitting for long periods would contribute to this (say during breastfeeding or at a desk job), but does does a C-Section.

41% of women gave birth to their babies in 2025 via C-Section(9). The C-Section procedure cuts through 6-9 layers of tissue, including skin, fat, facia, and muscle(10). When those tissues are sewn back together, they tighten the abdominal wall and pelvic floor, and could also put posterior pressure on the pelvis (leading to that flat back posture). Scar tissue is inelastic to begin with, but when a woman is healing, she will go out of her way to avoid pulling on the scar, because it hurts!!! Add to this the fact that she’s also looking after the baby, with this posture. It’s possible again, that without rehabilitation or guidance that she maintains this posture forever afterwards.

Some believe the hip flexor muscles are a core contributor to Lower Cross Syndrome. However, since the hip flexor group of muscles attach to all the lower back vertebrae, they can be both long and short in both Type A and Type B Lower Cross Syndromes. In women, I generally get better pelvic balance by lengthening the erector spinae. and stabilising the hip complex (more on this in a previous blog: Stretch with Caution)

All of these postures and syndromes either put extra pressure on pelvic floor and/or abdominal wall, or place them in a “less than optimal” position for function.

For this reason, when we are coaching “proper form” in my Women’s Strength and Conditioning program, I am only looking for “better” form, not perfect. Between all our different life experiences, we carry different scars, and have developed different ways of functioning. Working towards a more aligned posture is more achievable than insisting on perfect alignment from the start.

Like this? You might also like this mini course: Women’s Posture and Mobility

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If you’re in Narrabeen, You can order a trial of our Women’s S&C program here, or look up your closest Women’s Health Trainer here.

REFERENCES

(1) Limitless Chiropractic (2025) Why Spinal Curvature is Important limitlesschiropractic.co.nz, retrieved 18th May 2026 from https://limitlesschiropractic.co.nz/spinal-curvature-importance/

(2) Physio-Pedia (2024) Upper Cross Syndrome physio-pedia.com, retrieved 18th May 2026 from https://www.physio-pedia.com/Upper-Crossed_Syndrome

(3) Physio-Pedia (2024) Upper Cross Syndrome physio-pedia.com, retrieved 18th May 2026 from https://www.physio-pedia.com/Lower_Crossed_Syndrome

(4) Physio-Pedia (2024) Upper Cross Syndrome physio-pedia.com, retrieved 18th May 2026 from https://www.physio-pedia.com/Lower_Crossed_Syndrome

(5) Xu, Jingyu (2024) Prevalence of upper crossed syndrome: a systematic review and
meta-analysis Journal of Clinical Technology and Theory Vol 1, DOI: 10.54254/3049-5458/1/2024006

(6) Khaliq, A., Yaqub, S., Islam, F., Raza, A., Batool, A., & Jamil, S. (2021). RISK FACTORS ASSOCIATED WITH UPPER CROSSED SYNDROME IN FEMALES OF AGE 25-50 YEARS: A POPULATION-BASED CASE CONTROL STUDY. KHYBER MEDICAL UNIVERSITY JOURNAL, 13(4), 201–5. https://doi.org/10.35845/kmuj.2021.19840

(7) Shriya Das, Bibhuti Sarkar, Rachana Sharma, Malika Mondal, Pravin Kumar and Pallavi Sahay. (2017); PREVALENCE OF LOWER CROSSED SYNDROME IN YOUNG ADULTS: A CROSS SECTIONAL STUDY., Int. J. of Adv. Res., 5 (06), 2217-2228, ISSN 2320-5407. DOI URL: https://dx.doi.org/10.21474/IJAR01/4662

(8) Pailin Puagprakong (¹Department of Rehabilitation and Movement Science, Faculty of Sports Science, Kasetsart University, Nakhon Pathom 73140, Thailand), Aris Kanjanasilanont (¹Department of Rehabilitation and Movement Science, Faculty of Sports Science, Kasetsart University, Nakhon Pathom 73140, Thailand), Wannaporn S. Brady (²Department of Health and Sport Science, Faculty of Education, Mahasarakham University, Mahasarakham 44150, Thailand), and Kanphajee Sornkaew (³Department of Physical Therapy, Faculty of Allied Health Sciences, Naresuan University, Phitsanulok 65000, Thailand) Upper body posture changes during sitting in female office workers with lower crossed syndrome Hong Kong Physiotherapy Journal 2025 45:01, 35-43 10.1142/S1013702525500039

(9) AIHW (2025) National Core Maternity Indicators aihw.gov.au, retrieved 14th May 2026 from https://www.aihw.gov.au/reports/mothers-babies/national-core-maternity-indicators/contents/labour-and-birth-indicators/caesarean-section

(10) Gynaecology Hub (2025) C-Section Surgery gynecologyhub.com, retrieved 14th May 2026 from https://www.gynecologyhub.com/archives/1880