The goal of this blog is to help summarise the physiological understanding of how various tissues within the body heals. Please note that this is a rough guideline and can be drastically different depending on age, lifestyle factors and management. The three main tissues that we are concerned with as physiotherapists are bones, nerves and soft tissues.
SOFT TISSUE HEALING
Soft tissue is a broad term that is used to encompass muscles, tendons, ligaments and fascia or connective tissue. Since these tissues are intertwined and heal at similar rates we group them together for simplicity as rarely will they be injured in isolation. There are two main phases of healing: inflammatory and remodeling phase.
Inflammatory Phase:
After a soft tissue injury there is a release of inflammatory chemicals around the site of injury. These chemicals act to increase blood supply to the area, increase the sensitivity of the nerves surrounding the injury and start the domino effect of chemical process to begin healing (known as a biochemical cascade). This is the reason why some injuries will be painful, hot and swollen in the days to weeks following ab injury. This phase typically occurs 4-6 week post injury. Its hallmark is pain, stiffness and swelling. During this phase relative rest (NOT COMPLETE REST) is vital for ideal healing conditions.
Remodeling phase:
This phase occurs about 4-6 weeks post injury and can last ~6 more weeks (12 weeks post injury). Pain and swelling settle and your muscles and joints will gradually become less stiff. During this phase the body begins re-organising the soft tissues so they return to pre-injury state. This is where rehabilitation and strengthening is encouraged. The body will organize tissue in response to mechanical strain so it is very important to begin your rehab to provide physical stimulation for this to occur.
BONE HEALING
“Laughter might be the best medicine but maybe not for broken ribs”
Not the moste "humerus" of injuries as fractures can be very painfull, however they tend to repair very well. Bone healing has three main phases: inflammatory, bone production and bone remodeling.
The inflammatory phase is similar to that of soft tissues with an increase in blood flow and chemicals that start the healing process. This usually occurs during the first few days following a fracture.
Bone production follows. Blood and inflammation is replaced with fibrous tissue and cartilage (known as soft callus). Eventually the the soft callus is replaced with hard bone (known as hard callus). Hard callus can be seen on X-ray after ~4 weeks following fracture.
Bone remodeling is the last phase and typically occurs from week 6 to week 12. This is where the body compacts the hard callus to return the bone to a pre-fractured state. This compaction requires mechanics strain which is why rehab exercises are extremely important during this phase.
Exercises should be prescribed by a trained and experienced physiotherapist as too much strain will result in failed healing while too little strain will result in significantly deformed bones.
Management of fractures will vary based on site of fracture, how much strain the bone typically endures and severity of fractures. Whatever you do, please make sure you attend all your follow up X-rays and speak to your doctor and/or physio before removing and casts or braces.
Not to worry “it’s going tibia ok!”
Nerve healing
Nerve trauma can range from minor compression and bruising to severed nerves. These types of injuries can be incredibly complex and should never be managed without the help of multiple health professionals. The process under which nerves heal is very complex and poorly understood but the current literature can, at the very least, give us a rough idea on what to expect.
A minor bruising or nerve compression can typically take 6-12 weeks up to 6 months to resolve. Despite being classified as minor, any nerve trauma can be extremely painful as nerves are the structures that send pain signals to the brain. This type of nerve injury can result from direct trauma, indirect trauma such as whiplash, nerve compression in the periphery (peripheral nueropathy) or nerve compression at the spinal nerve root (radiculopathy).
A severed nerve can take a long time to recover. After the initial 4 weeks, severed nerves will typically grow at 1 mm per day so healing time frames are quite literally “how long is a piece of string?”. Sensory nerves that feel touch and temperature will typically recover with adequate management. Motor nerves (that control muscles) are more serious injuries because in the absence of nerve signals, the part of the nerve that connects to a muscle may wither away after 18-24 months. Advances in surgical techniques have made it possible to connect a severed nerve back to a muscle but should be carried out within 18 months of injury (or sooner).
If you have any further questions on how Bajan Physio can help you with your tissue healing journey, feel free to call or what’s app us on +12462532821 or email us on BajanPhysiotherapy@gmail.com