Anterior pelvic tilt

Scientific basis

In the sagittal plane, the pelvis tilts forward (anterior pelvic tilt) or backward (posterior pelvic tilt). Pelvic incidence, a fixed morphological parameter, equals the sum of pelvic tilt (PT) and sacral slope: when the pelvis tilts forward, sacral slope increases and pelvic tilt (PT) decreases.

The available range is influenced by pelvic morphology, including pelvic incidence. When sitting, the pelvis tends rather to tilt backward.

Blue Portance / SBNFA™ reading

In the SBNFA™ framework, anterior and posterior pelvic tilt describe the sagittal orientations that sitting engages or limits. Neither is “good” or “bad” in itself: each person has their own profile, shaped by their pelvic incidence.

Contribution to the analysis of sitting

Seating analysis observes pelvic orientation and its variations; it does not seek to bring an anterior or posterior pelvic tilt back to a reference value.

Not to be confused with

Posterior pelvic tilt, a backward tilt; pelvic incidence, a fixed parameter that anterior pelvic tilt does not change; hyperlordosis, an excessive deepening of the lumbar curve, which is not synonymous with anterior pelvic tilt; nutation, a movement of the sacrum relative to the iliac bones.

Related terms

Pelvic incidence · Pelvic mobility · Sacral nutation and counternutation · Sacral slope · Spinal profile · Posterior pelvic tilt · Pelvic tilt (PT)

Sources and scope

• Le Huec et al. (2011): pelvic parameters, origin and significance (European Spine Journal)
• Kouyoumdjian (2023): role of the hip-spine relationship in hip arthroplasty surgery (Revue de chirurgie orthopédique et traumatologique) (in French)