Type II somatic dysfunction

Fryette's laws are mechanical principles describing how the direction of spinal sidebending is coupled with the direction of rotation. In a neutral position, with the spine neither flexed nor extended, sidebending and rotation occur in opposite directions (the first law). In flexion or extension, they occur in the same direction (the second law). In integrative manual therapy, movement following this second law is called Type II motion. Type II motion is understood to occur individually at each spinal segment.

Sometimes, however, a segment becomes fixed in a flexed or extended position and cannot return to its original position. This is Type II somatic dysfunction. This approach explains it as one of the small joints between the vertebrae—a facet joint—becoming stuck in an open or closed position.

• Flexion lesion: The facet joint is fixed in an open position. The segment remains flexed, restricting backward bending.
• Extension lesion: The facet joint is fixed in a closed position. The segment remains extended, restricting forward bending.

How are they distinguished?

The bony projections on either side of the spine (the transverse processes) are examined by hand to see whether they protrude posteriorly. With a flexion lesion, the transverse process of just one segment feels prominent at the back when the lower back is extended; with an extension lesion, this happens when bending forward. The prominent side is the side toward which the vertebra is rotated, and it is also the side toward which it is sidebent. For example, if only one right-sided process becomes prominent when the lower back is extended, this is interpreted as a segment held in flexion, rotation to the right, and sidebending to the right (FRSR). This method is explained further in Positional diagnosis. If the prominence continues across two or more segments, it is Type I somatic dysfunction, rather than Type II. The key distinction is that only one segment is restricted.

Which segments are commonly affected in the lower back?

Integrative manual therapy textbooks describe Type II somatic dysfunction as common in the lumbar spine, with flexion lesions more frequent than extension lesions. In particular, they regard flexion lesions as almost always present at the fifth lumbar vertebra, and describe the fourth lumbar vertebra as sometimes showing a paired flexion lesion, rotated and sidebent in the opposite direction to the fifth. They also describe opposing patterns between the upper and lower segments as common at the junction of the thoracic and lumbar spine. Another feature of this approach is the view that problems in the middle lumbar segments (L2–L4) may be secondary changes linked to the abdominal organs.

What about limb joints?

In her clinical research, Sharon Weiselfish-Giammatteo concluded that limb joints have only Type II motion and no Type I motion. Type II somatic dysfunction is therefore also assessed in the hips, knees, ankles, shoulders, and wrists. In this approach, Type II dysfunction in limb joints is understood as a fixed combination of flexion or extension with abduction or adduction and internal or external rotation. These combinations are divided into four patterns in the hip and knee, and the most common knee pattern is described as a fixed combination of flexion, lateral glide, and external rotation.

Rather than a temporary symptom that suddenly appears and disappears, Type II somatic dysfunction tends to present as persistent discomfort with movement in a particular direction. For example, bending forward may feel fine while bending backward consistently makes the lower back ache, or a particular area of the knee may repeatedly feel as though it catches only when the knee is fully bent.

Integrative manual therapy holds that when this state persists, the surrounding muscles become tense protectively, and other joints compensate for the restricted movement, shifting the load elsewhere. When discomfort recurs in the same area, this approach therefore aims to identify and correct the responsible segment.

• Note which direction feels restricted. Recording specific directions, such as “Bending forward is fine, but it catches when I bend backward” or “The outside of my knee pulls when I bend it all the way,” can provide useful information during an assessment.
• Do not force movement in the restricted direction. Rather than forcibly bending or twisting a joint to make it crack, try moving slowly within a comfortable range of motion.
• Use a balanced variety of movements. Combining forward bending, backward bending, sidebending, and rotation can help reduce the tendency for a joint to become fixed in just one direction.
• Avoid staying in the same position for too long. If you spend long periods sitting, get up about once an hour and gently straighten your lower back.
• Relax during your treatment session. The main technique in this approach is Muscle energy technique. Usually, while you lie on your side, the practitioner positions your legs and trunk, then has you gently exert force for about 6–10 seconds and relax completely, repeating this three or four times. Except when the practitioner asks you to exert force, you can let your body rest comfortably in their hands.

If restricted movement is accompanied by any of the following signs, the problem may be something other than simple joint stiffness. Be sure to tell the practitioner before receiving manual therapy.

• Numbness or tingling spreading into an arm or leg, or weakness
• Pain severe enough to wake you at night
• Sudden restriction of joint movement after a fall or a hard impact
• Discomfort that keeps worsening over several weeks despite adequate rest