Body mechanics are a way of moving that protects our joints, muscles, other structural elements from pain and damage. You may have heard the phrase, "Form follows function". What this means is that the shape of one or more interacting parts dictates how motion can occur without causing damage. When we move in a way that our bodies are not accustomed to, or we move too frequently in one motion and not others, it can increase the chance of an injury occurring.
Let’s use back pain as an example:
Low back pain can often be reported by people who have to use their low back to perform repetitive manual tasks. One of the reasons for this is because some of the tasks they are using their low back for might be better suited for their thoracic spine or hip joints instead. The low back has very little rotation. You will see in the picture below how the joints meet in the sagittal (side view)plane allowing for very little motion with rotation.
In the thoracic spine (your mid-back), the joints meet in a coronal plane (front view) allowing for a generous amount of rotation. The thoracic spine can only move so far. That’s where the hips come in. As a ball-and-socket joint, the hip is a great rotator. The knees are not meant to rotate. What this means is a person who is twisting their low back with their foot planted can create unnecessary stress on both joint segments at the same time.
Here’s a shoulder girdle example:
The Shoulder blade moves up and out to the side (upwardly rotates) every time we reach overhead. The shoulder girdle is made up of 4 joints but let’s focus on just one, the STJ (scapulothoracic joint). 3 muscle groups are responsible for this movement here: Upper Trapezius, Lower Trapezius, and Serratus Anterior. The most common weakness found within this grouping is the Serratus Anterior. When it is weak the Upper Trap works extra hard and the blade moves up well enough but does not swing out to the side enough. The results can range from multi-site pain to shoulder impingement and everything in between.
No one teaches us body mechanics growing up or about its best friend, ergonomics, leaving us surprised and frustrated when an injury occurs. Physical Therapists are experts in the musculoskeletal system and how it should move. Getting strong includes assuring the right balance of muscular movement. Hence our slogan……… Make Movement Matter!