September 2009 Newsletter

However, a common problem occurs as the belly grows and the recti muscles begin to wander off laterally from the midline. This is usually due to excessive abdominal wall pressure overstretching (or tearing) the linea alba—a tendinous median line designed to separate the two rectus muscles. When working properly, the tendon effectively binds the recti muscles close to mid-line providing optimal abdominal support (Figure 1). Diastasis recti abdominis is the term used to describe the separation of abdominal wall musculature during some pregnancies.

If mother and therapist allow this slow lateral recti migration as the abdomen expands, vital trunk stabilizers including transversus abdominis, internal/external obliques and multifidi become stretch-weakened.

Gravity begins pulling the belly forward placing great strain on the low back extensor muscles. In the absence of proper front/back muscle balance, the posterior lumbar erectors tighten in an effort to restrain gravitational pull from the heavy unsupported belly. Regrettably, this only increases lumbar “bowing,” compressively loads the intervertebral discs and posterior facet joints, and creates greater low back pain.

Any alteration in the mother’s abdominal support system not only adversely affects fetal positioning but also causes our pregnant mothers to cry out for help as muscles, ligaments, joint capsules, and discs loose the battle with the unrelenting force of gravity. Fortunately, mothers receiving manual therapy from trained practitioners usually experience little low back pain through their pregnancies. Specially designed side lying techniques performed weekly or bimonthly can really help take pressure off the low back (Figure 2).