Hip fracture: Difference between revisions

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Hip fracture is a fracture in the femur (thighbone) just below the hip joint. Most at risk are white, post-menopausal women; Osteoporosis dramatically increases risk. Most hip fractures outside of this group are the result of high-trauma injuries, such as car accidents.

Definition

Any fracture of the thigh bone close to the upper end or involving the hip joint is a hip fracture. In the vast majority of cases a hip fracture is a fragility fracture due to a fall or minor trauma in someone with osteoporotic (weakened) bone. So the subject of "Hip Fracture" sometimes includes the complex consequences of Osteoporosis.

Synonyms

Most of the synonyms actually describe different types of hip fracture. All of these variations are important because each are treated differently.

Fractured Neck of Femur (sometimes Neck of Femur Fracture or NOF) denotes a fracture adjacent to the femoral head. This acronym (NOF) is sometimes loosely used for Hip Fracture.
Intertrochanteric or pertrochanteric fracture denotes a fracture which is a few centimeters lower and involves the Greater trochanter
Fractured Head of Femur or Head Splitting Fracture denotes a fracture involving the head itself. This is rarer and usually the result of high energy trauma and a dislocation of the hip joint.
Subtrochanteric fracture involves the shaft of the femur immediately below the Greater Trochanter and may extend down the shaft of the femur.

Incidence

Approximately 320,000 hospitalizations occur each year due to hip fractures in the USA, with similar proportions in other Western countries.

Pathogenesis/risk factors

Most hip fractures occur as a result of falls in elderly patients. For the thigh bone to break in these circumstances means it must be weaker than normal as similar or worse falls in young people do not usually cause the "hip fracture" pattern of injury. The commonest causes of weakness in bones are

Osteoporosis Hip fractures are one of the most serious consequences of osteoporosis; in fact a measure of success or failure of treatment of osteoporosis is the proportion of patients who sustain a hip fracture.
Other metabolic bone diseases such as Paget's disease, osteomalacia, osteopetrosis and osteogenesis imperfecta. Stress fractures may occur in the hip region with metabolic bone disease.
Benign or malignant primary bone tumours are rare causes of hip fracture
Metastatic cancer deposits in the proximal femur may weaken the bone and cause a pathological hip fracture
Infection in the bone is a rare cause of hip fracture.

The other major element in the risk of sustaining a hip fracture is the risk of falling. Falls Prevention is an important subject with concerns in the area of providing a safe environment for people at risk, custodial care, walking aids, medication issues etc. Hip Protectors are padded plastic shields that can be placed over the trochanters of people at risk of falling or of sustaining a fragility fracture. They are effective in reducing the likelihood of a hip fracture but it is a challenge to get people to wear them.

Classification (types of fracture)

There are two main types of fracture pattern - intertrochanteric fracture, and fractured neck of femur. The difference is important because the treatment and prognosis are different.

Fractured neck of femur

Fractured neck of femur involves the narrow neck between the round head of the femur and the straighter shaft. This fracture often disrupts the blood supply of the head of the femur - the part that makes up the hip joint.

Garden classified this fracture into four types:

Type 1 is a crack in the femoral neck with no displacement.
Type 2 is a break across the neck with impaction of the fracture but no displacement.
Type 3 involves displacement of the fracture (often rotation and angulation) but still some contact between the two fragments.
In type 4 there is complete displacement and no contact between the fracture fragments. The blood supply of the femoral head is much more likely to be disrupted in Garden types 3 or 4 fractures.

File:Nof garden3.jpg

Garden Type 3 Fractured Neck of Femur

File:Nof pauwels3.jpg

Pauwels type 3 (high angle) Fractured Neck of Femur

Surgeons may treat these types of fracture by replacing the bone with a metal prosthetic component cemented into the bone to replace the femoral head. Alternatively the treatment is to reduce the fracture (manipulate the fragments back into a good position) and fix them in place with metal screws or a screw-and-plate device. It has not yet been scientifically established whether one treatment is superior to the other.

Displacement and failure to heal can be problems when the fracture is fixed. Pauwels showed that if the angle of the fracture is too steep the injury is at risk of nonunion or malunion. Another serious complication of a fractured neck of femur is avascular necrosis. The fracture interrupts the blood supply to the head and the bone tissue of the head dies. Unless new living cells migrate into the dead area the femoral head will collapse causing pain and loss of function.

Intertrochanteric fracture

File:ITfx 31A2.jpg

Intertrochanteric Fracture

Intertrochanteric fractures occur slightly further down the bone and the fracture line crosses the Inter-trochanteric line between the two trochanters at the upper end of the femur. Because the fracture is lower the blood supply of both fragments is usually intact. This improves the chance of healing and reduces the likelihood of avascular necrosis.

The main concern in the classification of Intertrochanteric Fractures is the stability of the fracture pattern. When the fracture has many fragments (multifragmentary) there is a risk that it will shorten, rotate or angulate before it heals. When the Lesser Trochanter is broken off as a separate fragment the fracture is unstable and likely to collapse.

Natural history

Hip fractures are very dangerous episodes especially for elderly and frail patients. The risk of dying from the stress of the surgery and the injury in the first few days is about 10%. If the condition is untreated the pain and immobility imposed on the patient increase that risk. Problems such as pressure sores and chest infections are all increased by immobility. Eventually the untreated intertrochanteric fracture will heal but with a high likelihood of deformity, shortening of the bone and rotational mal-alignment. Healing of untreated fractured neck of femur is much less certain and displacement even more likely. The untreated prognosis of most hip fractures is very poor.

Clinical features

Symptoms

History of a provoking episode such as a fall or an accident.
Pain in the hip region
- Made worse by moving the thigh
- Usually so severe the patient is unable to walk
- May radiate to the knee
- If pain in the hip existed before the fall the patient should be investigated for a Stress fracture or a pathological deposit in the proximal femur.
The patient's general medical condition must be carefully assessed. It is often necessary to obtain a consultation from an Internist and/or Anaesthetist.
Risk factors for falling should be evaluated. The patient's social situation needs to be considered.

Signs

Signs involving provoking pain should only be elicited when there is doubt about the diagnosis. Usually the diagnosis is obvious and care should be taken to avoid hurting the patient.

Tenderness and swelling in the proximal thigh
Pain when the leg is moved or rotated
Pain on telescoping the limb
The affected leg is often shortened and externally rotated
Pulses and sensation are not usually changed by a hip fracture but should be checked.

Investigations

X-ray of the affected hip usually makes the diagnosis; AP and shoot-through lateral views should be obtained. In the rare situation where a hip fracture is suspected but does not show on plain Xray a CT scan with 3D reconstruction may be helpful. In cases more than 7 days post injury a bone scan may reveal a cryptic fracture.

As the patients most often require an operation, full pre-operative general investigation is required. This would normally include blood tests, ECG and Chest Xray.

External links

Orthopedics.com article on hip fractures
American Academy of Orthopedic Surgeons article on hip fractures
Fractures of the Femoral Neck Wheeless Textbook of Orthopaedics
Intertrochanteric Fractures Wheeless' Textbook of Orthopaedics

@@ Line 1: / Line 1: @@
-{{splitsections|Hip fracture treatment}}
 {{DiseaseDisorder infobox |
   Name        = Hip fracture |
@@ Line 63: / Line 61: @@
 ==Clinical features==
+{{main|Hip fracture treatment}}
 ===Symptoms===
 *History of a provoking episode such as a fall or an accident.
@@ Line 81: / Line 81: @@
 *Pulses and sensation are not usually changed by a hip fracture but should be checked.
-==Investigations==
+===Investigations===
 X-ray of the affected hip usually makes the diagnosis; AP and shoot-through lateral views should be obtained. In the rare situation where a hip fracture is suspected but does not show on plain Xray a CT scan with 3D reconstruction may be helpful. In cases more than 7 days post injury a bone scan may reveal a cryptic fracture.
 As the patients most often require an operation, full pre-operative general investigation is required. This would normally include blood tests, ECG and Chest Xray.
-==Treatment==
-===Non-operative treatment===
-If operative treatment is refused or the risks of surgery are considered to be too high the main emphasis of treatment is on pain relief. Skeletal traction may be considered for long term treatment. Aggressive chest [[physiotherapy]] is needed to reduce the risk of [[pneumonia]] and skilled nursing to try to avoid [[Bedsores|pressure sores]] and [[Deep vein thrombosis|DVT]]/[[pulmonary embolism]] Most patients will be bedbound for several months.
-===Operative treatment===
-Most hip fractures are treated by [[orthopedic surgery]], which involves [[medical implant|implanting]] an [[orthosis]]. The surgery is a major stress on the patient, particularly in older people. The injury is so painful that the patients suffer significantly and have to remain immobilized. Since prolonged immobilization can be more of a health risk than the surgery itself, post-op patients are encouraged to become mobile as soon as possible.  [[Physical therapy]] may be used to assist in this process.
-====Surgery for fractured neck of femur====
-[[Image:Shf ohne dislokation medial ap.jpg|thumb|120px|left|Medial fracture in a 92-year old woman]]
-[[Image:Shf medial verschraubt crop.jpg|thumb|100px|right|Fracture treated with [[cannulated screws]]]]
-For low-grade fractures (Garden types 1 and 2), standard treatment is fixation of the fracture in situ with screws or a sliding screw/plate device. This treatment can also be offered for displaced fractures after the fracture has been reduced.
-In elderly patients with displaced fractures many surgeons prefer to undertake a [[Hemiarthroplasty]], replacing the broken part of the bone with a metal implant. The advantage is that the patient can mobilize without having to wait for healing.<br clear="all" />
-====Surgery for intertrochanteric fracture====
-[[Image:Cdm hip fracture 343.jpg|thumb|left|120px|Intertrochanteric hip fracture in a 17-year-old male]]
-[[Image:Cdm hip implant 348.jpg|thumb|right|100px|Fracture supported by orthopedic implant]]
-An intertrochanteric fracture, below the neck of the femur, has a good chance of healing.  Treatment involves stabilizing the fracture with a lag screw and plate device to hold the two fragments in position.  A large screw is inserted into the [[femoral head]], crossing through the fracture; the plate runs down the shaft of the femur, with smaller screws securing it in place.
-Because the procedure to remove the [[orthosis]] is as serious an operation as the insertion, the hardware is typically left in the bone indefinitely.  Younger patients may consider having it removed; the plate functions as a [[stress riser]], increasing the risk of a break if another accident occurs.  Also, presence of the hardware can be problematic if an operation such as a hip replacement is required later in life.  Despite these risks, however, in recent years surgeons are more increasingly recommending not having the removal operation, due to the increased risk of fracture during the recovery period.<br clear="all" />
-====Prognosis post operation====
-Among those affected over the age of 65, 40% are transferred directly to long-term care facilities, long-term rehabilition facilities, or [[nursing home]]s; most of those affected require some sort of living assistance from family or home-care providers.  50% permanently require [[walker]]s, canes, or some other such device for mobility; all require some sort of mobility assistance throughout the healing process.
-Among those affected over the age of 50, approximately 25% die within the next year due to complications such as [[thrombus|blood clots]] ([[deep venous thrombosis]], [[pulmonary embolism]]), [[infection]]s, and [[pneumonia]].
-==Complications==
-===Of the injury===
-* Nonunion - [[Nonunion|failure of the fracture to heal]] This is common (20%) in Fractured Neck of Femur fractures but much more rare with other types of hip fracture. The rate of nonunion is increased if the fracture is not treated surgically to immobilize the bone fragments
-* Malunion - the fracture heals in a distorted position. This is very common. Shortening, varus deformity, valgus deformity and rotational malunion all occur quite often because the fracture may be unstable and collapse before it heals. With patients of limited independence and mobility this may not need to be treated but the intention of treatment is to prevent such problems.
-* [[Avascular necrosis|Avascular Necrosis]] of the Femoral Head - this occurs frequently (20%) in Neck of Femur fractures because the blood supply is interrupted. It is rare after Intertrochanteric Fractures.
-* Neurological and vascular injury as a result of the injury are rare
-===Of surgery===
-* Infection - deep or superficial wound infection has an approximate incidence of 2%. It is a serious problem as superficial infection may lead to deep infection. This may cause infection of the healing bone and contamination of the implants. It is difficult to eliminate infection in the presence of metal foreign bodies such as implants. Bacteria inside the implants are inaccessible to the bodies defence system and to antibiotics. The management is to attempt to suppress the infection with drainage and antibiotics until the bone is healed. Then the implant should be removed, following which the infection may clear up.
-* Implant failure - The metal screws and plate can break, back out or cutout superiorly and enter the joint. This occurs either through inaccurate placing of the implant or because the bone is so weak and brittle that the fixation does not hold. In some cases it may be necessary to revise to a [[Total hip replacement|Total Hip]]; in others the surgery may need to be re-done.
-* Mal-positioning - the fracture can be fixed and subsequently heal in an incorrect position; especially rotation. This may not be a severe problem or may require subsequent [[Osteotomy]] surgery for correction.
-===General medical complications===
-Many of these patients are unwell before they fall and break theirs hips. For some, the fall is part of the illness. Nevertheless the stress of the injury and the surgery does increase the risk of medical illness
-* [[Myocardial infarction|Heart attack]]
-* [[Cerebrovascular accident|Stroke]]
-* [[Pneumonia|Chest infection]]
-* [[Thrombus|Blood clots]]
-** [[Deep venous thrombosis]] (DVT) is when the blood in the leg veins clots and causes pain and swelling. This is very common after hip fracture as the circulation is stagnant and the blood is hypercoagulable as a response to injury. DVT can occur without causing symptoms.
-** [[Pulmonary embolism]] (PE) occurs when clotted blood from a DVT comes loose from the leg veins and passes up to the lungs. Circulation to parts of the lungs are cut off which can be very dangerous. Fatal PE may have an incidence of 2% after hip fracture and may contribute to illness and mortality in other cases.
-* [[Dementia|Mental confusion]] - this is extremely common following a hip fracture. It usually clears completely but the disorienting experience of pain, immobility, loss of independence, moving to a strange place, surgery and drugs combine to cause or accentuate dementia.
-*[[Urinary tract infection|Urinary Tract Infection]] (UTI) - Patients are immobilized and in bed for many days. They are frequently catheterised and UTIs are common.
-* [[Bedsores|Pressure sores]] - Prolonged immobilization and difficulty moving make it difficult to avoid pressure sores on the sacrum and heels of patients with hip fractures. Early mobilization is advocated to avoid this. Alternating pressure mattresses should be used for those unable to mobilize.
 ==External links==