A fractured neck of femur (FNOF) involves a fracture occurring in the location of the femoral neck (the weakest area of the femur). FNOF is primarily an injury of older people but may also occur in younger people with a history of violent trauma.
They are very common, with an incidence of 75,000 in the UK, set to rise to 100,000 by 2020. There is huge morbidity and mortality associated with this injury, with a 10% one-month mortality rising to 33% at one year. This is mostly due to patients being elderly and having multiple co-morbidities. Understandably this has large cost implications, currently costing the NHS up to 2 million pounds a year.
The fractured neck of femur best practice tariff was introduced due to variable care provision across the country. Sub-optimal care leads to longer hospital stays and poorer outcomes for patients. The best practice tariff aims to standardise treatment, to ensure best possible patient outcomes.
Osteoporosis / osteopenia
Trauma – often falls in the elderly
Pathological fractures – primary bone tumours or metastatic deposits leading to fracture
Common findings in the history
Fall (however may be atraumatic, particularly in pathological fractures)
May be felt in the hip, groin and knee
May be an exacerbation of pre-existing pain from another cause (e.g osteoarthritis)
Reduced mobility/sudden inability to weight bare
Classically the affected leg is shortened, ABducted and externally rotated
Exacerbation of pain on palpation of the greater trochanter
Pain is exacerbated by rotation of the hip
If you have a suspicion that the hip is fractured you should avoid vigorous examination as there is a risk of displacing the fracture.
Usually sufficient to make the diagnosis
If you have a high clinical suspicion and no X-ray diagnosis:
Gold standard is an MRI of the hip joint
This is often not quickly available, so CT is more commonly used in practice
Don’t forget that these patients often die from their co-morbidities.
Investigate and treat these co-morbidities (e.g. anaemia, AF, infections etc).
Regardless of the specific type of fracture, the initial management steps are the same.
Adequate analgesia (if available make use of regional anaesthesia techniques such as nerve blocks)
Bloods – group and save, FBC, U&E, LFTs, bone profile, coagulation
Correct any blood abnormalities – anaemia, dehydration, coagulopathy
Diagnose and treat co-morbidities – e.g. heart failure, pneumonia etc
Document pre-morbid state – e.g. could they mobilise independently prior to injury?
Screen for cognitive impairment – part of the best practice tariff – prognostically significant
Patients should be under joint care with a geriatrician.
Surgery needs to take place within 36 hours of admission.
Fractures are classified as extracapsular or intracapsular.
This is an important distinction because the management and risk of complications differ.
The main blood supply of the femoral head traverses under the capsule and along the femoral neck. As a result, the possibility of developing avascular necrosis of the femoral head is much more likely in intracapsular fractures (even more so in those involving displacement).
Grouped into four different types according to Garden classification
Group I & II refer to undisplaced intracapsular fractures
Group III & IV refer to displaced intracapsular fractures
Undisplaced intracapsular fractures (I & II)
Often impacted and likely to unite with bed rest
However, prolonged bed rest is associated with significant complications (thromboembolic disease/pneumonia etc)
As a result, the aim is to stabilise these fractures, to prevent displacement, usually with screws through the neck into the head of the femur
Displaced intracapsular fractures (III & IV)
High risk of avascular necrosis
Unlikely to unite
Hemi-arthroplasty is often recommended in the elderly, due to the risk of subsequent necrosis of the femoral head
Patients with pre-existing joint disease who are still fairly active and have a reasonable life expectancy should have a total hip replacement
In younger patients reduction and screws may be used, in an effort to preserve the patients own femoral head for as long as possible
As the name suggests, these fractures do not involve the capsule
As a result, the risk of avascular necrosis is much less
They can be further divided into displaced and nondisplaced, however, management is largely the same
In reality, undisplaced extracapsular fractures could quite easily be managed conservatively
However given the previously mentioned urgency to mobilise early, these fractures receive operative intervention
The most common surgical method of management involves a dynamic hip screw:
In this procedure, a screw is placed through the femur and into the femoral head
A plate is then attached along the femoral shaft which attaches to the screw
These fractures tend to collapse, so the plate allows the screw to slide along it
Collapse, despite sounding less than ideal, actually leads to a much more stable structure
If no contraindications present, day one mobilisation will be attempted.
Thromboprophylaxis – e.g. low molecular weight heparin
Ongoing MDT approach with orthogeriatric input.
Review bone protection – Vitamin D / Calcium supplements and Bisphosphonates
If the fracture was due to a fall, review medications for iatrogenic causes
Increased risk of thromboembolic events – deep vein thrombosis / pulmonary embolism
Avascular necrosis of the femoral head
Hip Fractures: The management of hip fractures in adults. Nice clinical guidance June 2011.
Surgical Talk. Revision in Surgery. 2005. Andrew Goldberg, Gerald Stansby