Fractures the Basics:
A fracture is defined as a break in the continuity of a bone and can be categorised as either being traumatic or pathological. A traumatic fracture occurs due to trauma, high impact activity or stress, whereas a pathological fracture is caused by a disease that has led to weakening of the bone. Medical conditions such as osteoporosis, osteogenesis imperfecta and cancers of the bone are a few examples.
Classification of fractures:
Broadly speaking fractures can be classified as open/closed, incomplete and complete.
An open fracture is where the bone is exposed or the wounds communicate with the fracture, as opposed to a closed fracture where the skin is intact. A complete fracture will mean that the bone has separated completely whereas an incomplete fracture would still have some bone fragments that are partially joined.
More specific classifications can be viewed below
Signs and symptoms of a traumatic fracture:
Apart from open fractures where the bone has exposed itself, it can be very difficult to diagnose a fracture without the use of an X-ray. This is particularly true with incomplete fractures. There are however various signs and symptoms that indicate that a fracture is likely to have occurred and those are:
Ø Swelling or bruising over a bone.
Ø General deformity over the injured site
Ø Pain in the injured area that gets worse when the area is moved or pressure is applied.
Ø Loss of function in the injured area.
Ø Crepitus (bony grating) may be heard or felt.
Ø Unable to weight bear with lower limb fractures
Ø Hip fractures will caused the lower limb to be shortened and externally rotated
Ø Fractures of the rib/sternum can cause difficulty breathing
Stages of fracture healing and healing rates
(Exact healing times are dependent on the severity and location of a fracture)
Stage 1.The inflammatory stage (3-5 days)
- The bone has a very good blood supply so the moment the bone is fractured there is a large amount of bleeding from the fracture fragments.
- This causes immediate swelling and bruising into the area of the broken bone
- Dead cells of the bone release chemicals known as cytokines that initiate the healing process
- Bone cells known as osteoclasts then remove the ‘dead’ cells
- When the blood begins to clot a mesh is formed which is the first link between the two fragments of bone
Stage 2. The Soft callus formation (4 days to 3 weeks)
-This mesh contains specialist cells called fibroblasts which begin to lay down granulation tissue between 4-10 days
-Chemical and metabolic reactions then take place and enable fibroblasts to lay down cartilage and fibro-cartilage
-This forms a spongy material between the two bone fragments but remains weak to externall stresses for around 6 weeks.
-After a couple of weeks despite being fragile the soft callus provides sufficient stability for new blood vessels to form.
Stage 3. Hard callus formation: from 2-3 weeks to 6 weeks (regarding upper limb fractures) 12 weeks (Lower Limb fractures)
-Bone cells known as osteoblasts then begin laying down what is known as ‘woven bone’
-Woven bone is soft and disorganised but it’s the first bone contact between the two fragments
-Depending on the location and severity of fracture the soft callus will then be completely transformed into woven bone
-Hard Callus formation is a complex process that is guided by the release of mineral compounds such as Calcium and Phosphate into the Cartilage tissue, which subsequently transforms into a bridge of Hard Callus over the fracture site.
-Once the Hard Callus has formed at the former fracture site, then fracture Union is said to have occurred. Fracture Union can be seen on x-ray at around six weeks in upper limb fractures and twelve weeks in lower limb fractures.
Stage 4. Bone remodelling (up to several years)
-During normal bone healing the body will lay down more hard callus than is needed to unite the fracture fragments. As a result the fracture site looks enlarged when viewed on x-ray.
-Over time the normal shape of the bone is restored. Bone is laid down where it is needed by Osteoblasts and removed by Osteoclasts
-The loosely organised Woven bone is gradually replaced by lamellar bone, which is highly organised along lines of stress and therefore much stronger than Woven bone.
Spinal fractures: A spinal fracture is a serious injury but fortunately far less common than a fracture of the periphery. The most common fractures of the spine occur in the thoracic (mid-back) and lumbar spine (lower back).
Classification of spinal fractures:
Stable and unstable fractures are a basic from of classification for spinal fractures.
Stable fractures will not cause spinal deformity or any neurologic (nerve) problems. In other words although a fracture is present is doesn’t pose any serious harm and will not cause symptoms such as numbness, lack of sensation or paralysis. With a stable fracture, the spine can still carry and distribute your weight.
Unstable fractures make it difficult for the spine to carry and distribute weight. Unstable fractures have a chance of progressing and causing further damage. They may also cause spinal deformity and have adverse effects on the spinal cord.
More specific classifications are as follows:
Compression fractures: The most common spinal fracture as it typically seen as a pathological fracture from osteoporosis. This type of fracture is usually stable and rarely associated with neurological problems. This occurs when the vertebrae can no longer handle the stress that is placed upon it.
Burst Fracture: Burst fractures are caused by severe trauma. They happen when the vertebra is essentially crushed by extreme forces. Unlike compression fractures, it's not just one part of the vertebra that's fractured. In a burst fracture, the vertebra is fractured in multiple places. Because the vertebra is crushed completely, bony fragments can spread out and cause spinal cord injury. Burst fractures are more severe than compression fractures.
Flexion-distraction Fractures: This type of fracture occurs when there is a sudden forward movement that places incredible stress on the spine, it may break a vertebra or vertebrae.
Fracture-dislocation: If you have any of the above fractures and the vertebra(e) moves significantly (dislocation), you have a fracture-dislocation, this is a very unstable fracture
Signs and symptoms of spinal fractures:
Spinal fracture symptoms and the severity of those symptoms vary based on what type of spinal fracture you have, the symptoms also vary depending on whether the spinal fracture is causing nerve problems.
More severe spinal fractures could have the following symptoms:
-Muscular weakness in your arms or legs
-Numbness in your arms or legs
-Bowl/bladder problems/ incontinence
-Shooting pain and constant pins and needles that travels down your arms and legs
-Paralysis (in rare circumstances)
-Compression fractures, a type of spinal fracture normally associated with osteoporosis or other conditions that weaken your bones, can involve other symptoms not listed above. If, for example, you have multiple compression fractures, you can lose height and/or notice a hump in your spine (kyphosis)
Stress fractures: a common injury and most cases are associated with athletes.
Pathology: An incomplete fracture of the bone most commonly seen in the mid shaft of the tibia or metatarsals caused by unusual or repetitive stress. It is a fracture that occurs over time as the repetitive stress exhausts the capacity of the bone to remodel itself. In other words the ‘breakdown’ of bone surpasses the rate in which the bone is able to heal itself.
Presentation: Few symptoms are seen with stress fractures and it is very difficult to diagnose as X-rays will unlikely show evidence due to the ‘hairline’ nature of the fracture. A bone scan or MRI would be more effective. Over the site there will be a generalised area of pain and tenderness. If the stress fracture occurs on a weight bearing bone it will be made worse with weight bearing/ running and the most pain will be felt at the beginning and end of a run, there may be occasional bruising on the site.
Treatment/Rehab: The only treatment for a stress fracture is rest. PRICE can be applied with flare-ups and acute episodes, so a stress fracture can be treated like an inflammatory pathology to some extent. Healing times vary depending on numerous factors but typically stress fractures last between 4-8 weeks, though it is not uncommon for the more severe stress fractures to last around 16 weeks. After these periods activities can be gradually resumed, but training intensity and progression should follow the rule of ‘10’ where the volume of training is only increased by no more than 10% each week on a given variable. Quad strengthening and VMO exercises should also be given to prevent atrophy and secondary complications.
Secondary pathway: in the most severe fractures surgery may be required which could involve pinning the fracture in order for it to heal properly this will require 6 months rehab