Microtrauma is any of many possible small

injuries An injury is any physiological damage to living tissue caused by immediate physical stress. An injury can occur intentionally or unintentionally and may be caused by blunt trauma, penetrating trauma, burning, toxic exposure, asphyxiation, or ...

to the body. Microtrauma can include the microtearing of muscle fibres, the sheath around the

muscle Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscl ...

and the

connective tissue Connective tissue is one of the four primary types of animal tissue, along with epithelial tissue, muscle tissue, and nervous tissue. It develops from the mesenchyme derived from the mesoderm the middle embryonic germ layer. Connective tiss ...

. It can also include stress to the

tendon A tendon or sinew is a tough, high-tensile-strength band of dense fibrous connective tissue that connects muscle to bone. It is able to transmit the mechanical forces of muscle contraction to the skeletal system without sacrificing its ability ...

s, and to the

bone A bone is a Stiffness, rigid Organ (biology), organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red blood cell, red and white blood cells, store minerals, provid ...

s (see

Wolff's law Wolff's law, developed by the German anatomist and surgeon Julius Wolff (surgeon), Julius Wolff (1836–1902) in the 19th century, states that bone in a healthy animal will adapt to the loads under which it is placed. If loading on a particular ...

). It is unknown whether or not the

ligament A ligament is the fibrous connective tissue that connects bones to other bones. It is also known as ''articular ligament'', ''articular larua'', ''fibrous ligament'', or ''true ligament''. Other ligaments in the body include the: * Peritoneal li ...

s adapt like this. Microtrauma to the skin (compression, impact, abrasion) can also cause increases in a skin's thickness, as seen from the

callus A callus is an area of thickened and sometimes hardened skin that forms as a response to repeated friction, pressure, or other irritation. Since repeated contact is required, calluses are most often found on the feet and hands, but they may o ...

es formed from running barefoot or the hand calluses that result from rock climbing. This might be due to increased skin cell replication at sites under stress where cells rapidly slough off or undergo compression or abrasion. Most microtrauma cause a low level of

inflammation Inflammation (from la, wikt:en:inflammatio#Latin, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or Irritation, irritants, and is a protective response involving im ...

that cannot be seen or felt. These injuries can arise in muscle, ligament, vertebrae, and discs, either singly or in combination. Repetitive microtrauma which are not allowed time to heal can result in the development of more serious conditions.

Negative effects

Back pain Back pain is pain felt in the back. It may be classified as neck pain (cervical), middle back pain (thoracic), lower back pain (lumbar) or coccydynia (tailbone or sacral pain) based on the segment affected. The lumbar area is the most common area ...

can develop gradually as a result of microtrauma brought about by repetitive activity over time. Because of the slow and progressive onset of this internal injury, the condition is often ignored until the

symptoms Signs and symptoms are the observed or detectable signs, and experienced symptoms of an disease, illness, injury, or condition. A sign for example may be a higher or lower temperature than normal, raised or lowered blood pressure or an abnormali ...

become

acute Acute may refer to: Science and technology * Acute angle ** Acute triangle ** Acute, a leaf shape in the glossary of leaf morphology * Acute (medicine), a disease that it is of short duration and of recent onset. ** Acute toxicity, the adverse eff ...

, often resulting in disabling

injury An injury is any physiological damage to living tissue caused by immediate physical stress. An injury can occur intentionally or unintentionally and may be caused by blunt trauma, penetrating trauma, burning, toxic exposure, asphyxiation, o ...

. Acute back injuries can arise from stressful lifting techniques done without adequate recovery, especially when experimenting with more ballistic work, or work where the extensor spinae are stressed during spinal flexion when much of the load is commonly taken up by the slower to heal ligaments which may not adapt progressively to the stress. While the acute injury may seem to be caused by a single well-defined incident, it may have been preventable or lessened if not for the years of injury to the musculoskeletal support mechanism by repetitive microtrauma.

Positive effects

After microtrauma from stress (such as lifting weights) to muscles, they can be rebuilt and overcompensate to reduce the likeliness of re-injury.

References

{{reflist Injuries Musculoskeletal disorders