Recent Advances in the Assessment and Treatment of the Sacroiliac Joint – Stability &The Role of Motor Control

A primary function of the pelvis is to transfer the loads generated by body weight and gravity during standing, walking, sitting and other functional tasks. How well this load is managed dictates how efficient function will be. The word ‘stability’ is often used to describe effective load transfer and requires optimal function of three systems: the passive (form closure), active (force closure) and control (motor control) (Panjabi 1992). Collectively these systems produce approximation of the joint surfaces (Snijders & Vleeming 1993a,b). The amount of approximation required is variable and difficult to quantify since it depends on an individual’s structure (form closure) and the forces they need to control (force closure). The following definition of joint stability comes from the European guidelines on the diagnosis and treatment of pelvic girdle pain (Vleeming et al 2004).