Post-isometric muscle relaxation

Post-Isometric Muscle Relaxation (PIRM) — a technique that leads to muscle relaxation after voluntary (conscious) muscle tension, without changing the distance between the muscle’s attachment points. It is typically an essential part of almost all leading directions and schools in manual medicine.

PIRM belongs to the most gentle, effective, and safe methods for treating spinal diseases and myofascial structures.

Properly performed mobilization using PIRM can completely replace manipulation, which carries a higher risk of complications. The analgesic and myorelaxant effects of both approaches are practically equal, but the results achieved through PIRM tend to be significantly more stable and long-lasting.

The PIRM method is based on physiological muscle tension and relaxation and is most often used before joint mobilization.

PIRM:

Promotes the release of fascial-muscular rigidity;
Eliminates peripheral pain foci — trigger points;
Activates high-threshold mechanoreceptors of type III located at the insertion sites of ligaments and tendons into the joint capsule;
Activates afferent innervation and normalizes neuromuscular connections.

This technique is aimed at eliminating reflexive muscle spasms that may intensify during mobilization. When there is a functional block in a spinal segment in one direction, the muscles responsible for movement in the opposite direction often become spastic. To relieve this spasm, a small isometric load must be applied against resistance in the opposite direction. Repeating these loads several times with 10–15 second intervals (the duration of each isometric contraction also being 10–15 seconds), it is possible to relax the affected muscle and remove the blockage.

Relief of functional-muscular rigidity and normalization of muscle tone are usually achieved by the end of the first PIRM session. However, due to the presence of dominant pathological information in the suprasegmental areas of the central nervous system and the physiological laws of muscle contraction, 3–7 sessions per course are necessary to achieve lasting improvement.

Indications for performing PIRM include:

Poly- and mono-segmental, moderately or severely painful functional blocks of any localization;
Myodystonic and myodystrophic tissue changes in painful muscular syndromes of any localization;
Muscle shortening due to regional postural imbalance;
Presence of active and latent trigger points in soft tissues;
Localized muscle hypertonus;
Musculoskeletal pain not only of vertebrogenic and visceral origin but also of other causes (such as cold exposure, trauma, scars);
Use of PIRM as a preparatory stage (mobilization) before performing manipulations.