The Pelvis and Stability

The movement shown here is one way to assess how well you can control your pelvis in the frontal plane (see below.) I don't like to say "drop" as that gives an impression of letting your hip fall, rather than controlling the downwards motion like you should do.

Image from The Human Pelvis: Variation in Structure and Function During Gait (anatomypubs.onlinelibrary.wiley.com)

It's become almost a reflex within the fitness industry to prescribe isolated core exercises in response to any lower back/hip related problems. Not excluding myself - I'm sure I've written something along those lines before too.

It often helps. Sometimes it doesn't.

In a city like Hong Kong, back pain is a common problem, especially among those of us who have to sit for long stretches of the day.

Often overlooked is how well our pelvis can move. After all, the pelvis is the connection between our spines and our lower body.

Our bodies are complex and three-dimensional, not just front-and-back or up-and-down. So while it's tempting to give the easy prescription (the back hurts, so let's work on the front; the hips hurt, let's work above that), we should always assess a person's movement, personal history and lifestyle habits individually, instead of giving a one-size-fits-all solution.

Here are some studies to consider when thinking about the role the pelvis plays in stabilizing our spines, as well as in daily movement like walking:

- Pelvic motion the key to understanding spine–hip interaction (ncbi.nlm.nih.gov)

"The pelvis stands as the cornerstone between the spine and the hips. Pelvic motion is essential to maintain proper balance and sagittal alignment during bipedalism, and retroversion is recruited as a compensation mechanism when spinal malalignment occurs.

Patients with flexible lumbar spines (spine users) protect the hip joint. Patients with stiff (degenerated or fused) lumbar spines (hip users) demand higher hip mobility."

- The Human Pelvis: Variation in Structure and Function During Gait (anatomypubs.onlinelibrary.wiley.com)

"During human gait, the pelvis has motions about all three axes. The magnitude of these motions is partially dependent on walking speed, with larger motions occurring at faster walking speeds"

"[...] normal pelvic motion plays a role in reducing exaggerated movements of the center of mass. Furthermore, the importance of the normal movement of the pelvis during gait has been highlighted in recent work. Restrictions of pelvic motion, as can occur in robotic assistive devices, lead to compensation in upper and lower extremity kinematics"

"The pelvic motions during gait serve to optimize the movement of the center of mass, producing smooth and energetically efficient locomotion."

Lastly, some useful visuals on the relationship between the femur and pelvis:

- Pelvic-on-Femoral Osteokinematics (clinicalgate.com)