Muscle Repair

Original Editor - Lucinda hampton

Top Contributors - Lucinda hampton  

Introduction

Skeletal muscle repair requires the activation of satellite cells, which are the residential muscle stem cells. The repair/regeneration is a highly coordinated process, involving cell-cell, cell matrix and extracellular matrix interactions. Immune, fibrotic, vascular and myogenic cells all play a role in the three phases of muscle repair/ regeneration. These phases

1. Destruction phase : distinguished by rupture and necrosis of the myofibers, formation of a hematoma and an critical inflammatory reaction.
2. Regeneration phase: phagocytosis of damaged tissue preceding myofibers regeneration, leading to satellite cell activation.
3. Remodelling phase: maturation of regenerated myofibers with recovery of muscle functional capacity and fibrosis and scar tissue formation.

Wound healing phases

Skeletal muscle injuries can be caused by a multitude of events that may be direct trauma eg muscle lacerations and contusions or indirect eg strains and degenerative diseases. With minor muscle injuries regeneration is naturally repairs eg post quadriceps strain. On the other hand post severe trauma or degeneration, muscle healing is incomplete, often resulting in the fibrotic tissue with reduced functional capacity.

Following muscle injury a few days of rest is useful, when the aim is to control inflammation, oedema and pain. This immobilisation time gives the newly formed scar tissue a necessary tensile strength to withstand the forces caused by muscle contractions. Longer immobilisation has adverse effects namely atrophy of healthy muscle, excessive deposition of connective tissue in the muscle tissue and a delay in the return of the injured muscle strength.

Physiopedia has many great muscle repair related pages. Take a look at the following links to get a deeper understanding.

• Satellite Cells
• Soft Tissue Healing
• Muscle Injuries: Regeneration Strategies
• Muscle Injuries