Fractures 1

Orthopedics: Fractures
General Info
-          fractures can involve part of, or all of the bone cortex
-          Open fracture – the skin or overlying mucous membrane is breached
-          Closed – there is no damage to the overlying skin or mucous membrane
Types of Fracture
 
Presentation
-          Fractures are always Painful!
-          Often involve trauma (except for pathological fractures)
-          Tender
-          Often swollen
-          Mobile at fracture site
-          Loss of limb function
Investigations
See also the article on Bone Radiology
-          X-ray – the investigation of choice.
o   All suspected fractures should be x-rayed from 2 planes! – AP, and lateral. This allows you to judge the level of displacement, comminution, angulation and rotation.
-          Bone scans – if you can’t see a fracture on X-ray, but you still highly suspect one, then you might do a bone scan. There is increased Tc uptake at sites of fracture, so fractures will appear dark on bone scan.
o   This effect is less apparent in older patients due to reduced osteoblastic responses to the scan. In such patients, you might have to wait one week between giving the radioactive isotope and performing the scan.
o   Particularly useful for femoral neck and sacral injuries in the elderly, and carpal tunnel injuries in the young.
-          CT – useful if you can’t see anything on x-ray. Make sure the scan is perpendicular to the fracture line!
o   CT is also very good at detecting new bone formation, and so can detect subtle stress fractures.
-          MRI – once again, useful if x-ray looks normal. MRI’s can be especially good, as a T1 scan can show the fracture immediately, (bone scans and CT can take a while), whilst T2 are good for showing up older fractures.
General Complications of Fracture
Early Complications
-          DVT and PE – possibly the most common post fracture complication. Take preventative measures:
o   Stockings
o   Leg pumps
o   LMW heparin (in selected patients!)
·         Compartment Syndrome – full article
-          Vascular injury
o   May lead to avascular necrosis - this usually occurrs in the hip, but can occur at the end of any long bones, sometimes without associated fracture! Tends to occur within 48 hours of fracture. Needs to be treated with a total hip replacement (THR). X-ray will be normal in the early stages, but in the late stages, affected bone areas will be darker than normal bone, due to collapse of subchondral bone.
o   Generally rare, but well recognised
o   Usually associated with open, high energy fractures.
o   Signs include; cold pulseless limb, ischaemia, paralysis and parasthesia of the limb
§ If there is ischaemia, you should presume there is arterial disruption until proven otherwise.
§ Angiography confirms the diagnosis
§ Treated with surgery to revascularise the limb. Also, often just closing an open fracture can help perfusion.
·         You may use a temporary vascular shunt to prevent damage whilst more permanent surgery is performed
·         The limb should be fixated before you operate on the vessels
·         Nerve Injury – particularly if the fracture affects the knee (common peroneal nerve). Look for foot drop and loss of sensation on the dorsum of the foot. The majority of nerve injuries are traction neuropraxia – i.e. the nerve remains intact, but is temporarily unable to transmit nerve impulses. These will subsequently recover. Prognosis for nerve injury is generally good, but many patients might not make a complete recovery
§ It is important to make detailed notes and examination of nerve injury before surgery – as if the nerve injury is only noted after surgery, the surgeon may be liable.
-          Vascular injury
Late Complications
·         Mal-union – the separate areas of bone heal, but with incorrect alignment. Proper placement and reduction of the fracture at the time of injury can prevent it.
·         Nonunion – the separated areas of bone do not fuse. More common in smokers. Often occurs when a fracture is ‘missed’ on x-ray and thus the correct treatment is not administered (e.g. immobilisation in a cast). There is usually some tissue development between the two fractured pieces. This can be scar tissue, or more rarely, a pseudo joint forms with cartilaginous articulating surfaces. If union has not occurred by 6 months, then it is unlikely to do so without intervention. Typically a diagnosis of non-union requires an x-ray at >6 months demonstrating non-union of the fractured ends of the bone.
·         Delayed union – difficult to distinguish between delayed and non-union. X-ray at 6 months is definitive. In both instances the joint is likely to be painful throughout.
Other complications
-          Infection
o   Can be early or late
o   Gas Gangrene
§ Infection, usually by chlostridium, that produces gas within tissues. Rare.
·         Algodystrophy – (Sudeck’s Atrophy) – aka Reflex sympathetic dystrophy syndrome and Complex regional pain syndrome
·         This typically occurs in the hand or foot after injury, sometimes after only mild injury. It occurs after about 5% of all trauma injury, and can also occur after frostbite and long periods of immobilisation.
·          It results from injury to the sympathetic nervous system which inturn, affects the blood supply to the affected region.
·         Typical features include:
o   Burning pain in the affected area
o   Skin changes – skin often becomes thinned and shiny
o   Swelling
o   excessive sweating – at the affected site
o   Pain stiffness and muscle wasting may become worse with progression, as the patient is reluctant to use the affected body part.
·         It can often be successfully treated with physiotherapy, although this can be a lengthy process
Hip Fractures - Neck of Femur (NoF)
-          The most common type of fracture
-          Typically occur in elderly female patients
o   Also common in high impact trauma – e.g. car accident
o   Female:Male ratio is 4:1
o   Mean age is 75
o   Dementia or cognitive impairment present in 30% of cases
-          The majority will require corrective surgery
-          Mortality – 20-35% in the first year
o   80% of mortality is in women
Types
-          Extracapsular – fractures that occur outside the joint capsule
o   Do not affect the blood supply to the femoral head
o   Typically occur in well vascularised bone, and thus complications of bone union are rare
o   Often described as stable, ort unstable. Unstable fractures are generally those where there is detatched fragment of lesser trochanter.
-          Intracapsular – fractures that occur inside the joint capsule
o   Can affect the blood supply to the femoral head, especially if the fracture is displaced.
o   Complications of fracture union are common
Presentation
-          History of fall / trauma
-          Leg may be shortened and externally rotated in displaced fractures.
-          10% will have a fracture at another site, usually proximal humerus, or distal radius.
-          Neurovascular injury is rare…
o   But avascular necrosis is more common here than at other sites. Often treated with total hip replacement.
o   The sciatic nerve is at risk in dislocation fractures, and dislocations (15% of patients).
Treatment
Nearly all will be given surgery, unless there are significant CI’s.
-          Intracapsular fractures:
o   Undisplaced – up to 15% will displace without treatment, and thus the usual treatment is internal fixation using a dynamic hip screw.
§ 5% will have avascular necrosis – these cases will need arthroplasty (hip replacement)
o   Displaced – can be treated by reduction and fixation, but there is a high risk of non-union, and fixation failure. 15% will have avascular necrosis .40% of patients treated in this way will require arthroplasty at some point in the future. Thus, many surgeons opt for hemiarthroplasty as the first line. In hemiarthroplast, the femoral head but not the actebular cup is replaced. (In a total hip replacmenet both the head and the cup are replaced, but this is typically reserved for osteoarthritis).
§ Reduction and fixation more likely to be carried out in younger patients – as long as there is no underlying pathology (e.g. steroids causing osteoporosis) that caused the initial fracture.
-          Extracapsular fractures
o   Internal fixation is the treatment of choice for inter-trachanteric fractures. as the blood supply to the femoral head is not in danger. Unlike intracapsular fixation, a sliding screw and plate fixation  (aka Dynamic Hip Screw) is used. AN intra-medually hip screw is used for sub-trochanteric fractures. Other methods may be used for fractures that extend a long way down the femoral shaft. Complications include:
§ Failure of fixation (5%)
§ Non-Union – (1-2%)
§ Infection (5%)
Dynamic Hip Screw Intra-Medually Screw
Dynamic Hip Screw - almostadoctor.com - free medical revision notes
Intramedually Hip Screw - almostadoctor.com - free medical student revision notes
Prognosis
This is generally poor, irrespective of the fracture location. This tends to be a reflection of the general health of the patient’s involved (elderly women), and not an indication of the surgery itself.
-          1 year mortality – 30%
-          1 year mortality in those with dementia – 50%
-          Only 70% of patients will return home. The rest will require residential care for the rest of their lives
Upper Limb Fractures and Dislocations
Dislocated Shoulder
-          Patient will support affected arm with other arm
-          Dislocation usually occur anteriorly – thus traumatic injury is often from behind
-          Should may appear ‘flattened’
-          Palpation of the joint will reveal displaced greater tuberosity, and unusual bulge below the clavicle.
-          May be anaesthesia over the attachment of deltoid (axillary nerve)
-          Treatment
o   Can try to relocate the joint manually
o   Will often spontaneously resolve in a few weeks
Fracture of shaft of humerus
-          Common traumatic injury in the elderly
-          Extensive bruising of the upper arm
-          Wrist drop common – due to involvement of the radial nerve which runes in the spiral groove of the humerus. In closed injuries, the nerve damage is usually reversible (traction neuropraxia)
-          Treatment – as long as the injury is closed, then splitting of the wrist and a cast over the break is usually sufficient to allow for healing
Suprecondylar fracture of the humerus
-          Only really seen in childhood, but it is a common fracture for children
-          The humerus fractures just above the condyles, and the distal fragment can be pushed and twisted. This poses a risk to the brachial artery, which if damaged, can result in severe limb ischaemia.
o   You should always check the radial pulse, which checks the integrity of the brachial artery!

Fracture of the Radial Head
-          Often caused by falling onto an outstretched hand
-          Can be difficult to see on x-ray, particularly if it is not displaced
-          Typical signs include:
o   Displacement of the fat pad
o   Effusion of the elbow
o   Decreased range of elbow movement – particularly extension – which can last for several months
Colle’s Fracture – distal radial fracture
-          Results from falling onto dorsiflexed (outstretch) hands, with resultant posterior displacement of the wrist. The term colle's fracture however is however sometimes applied to almost any fracture of the distal radius.
-         Management - if undisplaced, cast alone is usually successful. slight displacement and angulation can be treated with closed reduction (manipulation of the fracture without surgery, with plenty of pain releif!). Large displacements require surgery to correct, and often there is some form of internal fixation. rarely, external fixation is also used.
-         Complications - 
Colle's Fracture
 Colle's fracture - almostadoctor.com - free medical student revision notes
Smith’s Fracture – distal radial fracture
-          The reverse of Colle’s – results from falling onto a palmar flexed wrist

Chauffer’s fracture – distal radial fracture
-          Fracture of the styloid of the radius, usually due to compression of this against the scaphoid
-          Caused by falling onto a dorsiflexed hand
-          Gets its name from the fractures seen when Chauffer’s, when cranking a car’s engine would break their wrist when the engine backfired.
Scaphoid Fracture
-          The scaphoid bone articulates with the distal end of the radius.
-          Nearly always the result of falling onto a dorsiflexed (outstretched) hand
-          Often the diagnosis is missed as it can be very difficult to see on x-ray
o   May be misdiagnosed as a ‘sprained wrist’
-          Patients will have a feeling of ‘fullness’ or pain in the anatomical snuffbox – the depression between the tendons of the thumb when the thumb is fully extended and abducted
-          Treatment
o   Immobilisation of the joint is necessary. Without this, the scaphoid may not unite properly, and there can be necrosis of the scaphoid, resulting in prolonged pain and weakness in the wrist.

Fracture of the Elbow
-          Often result from falling on an outstretched arm
-          Can be very difficult to see on x-ray. Look for the posterior fat pad sign which is visible as a slight dark patch behind the elbow, on the lateral view.
o    Fracture may be more visible after 10 days, so consider re-x-ray
-          Pain relief is important for the first couple of weeks, but it is really important to mobilise the joint early to prevent permanent loss of extension. Patients should be encouraged to use the affected arm as much as pain allows and as soon as possible.


Notes by Tom Leach

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March 16, 2013 at 5:16 AM delete

Useful information, thank you very much.

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