Pelvic and hip fractures

• A pelvic ring fracture is a high-energy, sometimes life-threatening injury in which the bony ring of the pelvis is disrupted; the real danger in the first hours is bleeding, not the bone itself. ^[5]
• The first priorities follow the Advanced Trauma Life Support (ATLS) approach: stop exsanguination, then find and fix the source of bleeding with a pelvic binder, pelvic packing or angioembolisation.
• Apply a pelvic binder at the level of the greater trochanters early, give intravenous tranexamic acid ideally within one hour, and do not spring the pelvis on examination.
• Hip (proximal femoral) fracture is the commonest serious fall injury in older adults, mainly women over 70, and kills about 30% of patients within one year.
• Operate on a hip fracture on the day of, or the day after, admission, with a cemented arthroplasty for a displaced intracapsular fracture, and run the whole pathway through an orthogeriatric programme. ^[1]

By the end of this page you should be able to:

1. Recognise a pelvic ring injury, explain why it bleeds, and carry out the initial haemorrhage-control steps in order.
2. Use the ABCDE approach and a pelvic binder safely, and choose between interventional radiology and pelvic packing.
3. Classify common hip fractures and match each to its operation and implant.
4. Plan perioperative care: timing of surgery, analgesia, anticoagulation, fluids and delirium prevention.
5. Describe an orthogeriatric Hip Fracture Programme and the long-term complications of both injuries.

A pelvic fracture is any break of the pelvic bones or the joints that connect them. The injuries that matter for shock are the pelvic ring injuries, in which the ring formed by the two innominate bones and the sacrum is disrupted in two or more places. A single break of one pubic ramus without ring disruption is usually stable and does not carry the same bleeding risk.

Pelvic fractures are present in 7% of trauma patients.^[2] In young adults with a median age around 39 years, high-energy road traffic accidents predominate and account for 62.9% of pelvic fractures.^[2] In patients over 65, a low-energy fall from standing height becomes the major cause and accounts for 83% of cases.^[2]

The Young-Burgess classification is the most popular system and is built into ATLS. It groups injuries by mechanism: antero-posterior compression, lateral compression and vertical shear. Vertical shear fractures are the most dangerous pattern: 78% of patients present in haemorrhagic shock and 58% die.^[2] Combined mechanisms account for about 5% and vertical shear for about 3% of injuries in reported series.^[2]

Pelvic fractures are also described by stability. An unstable pelvic ring moves under load and keeps bleeding. The BOA's standards programme recognises trauma standards for pelvic fracture management and standards for the care of older or frail orthopaedic trauma patients, and the 2018 pelvic fracture BOASt is the document that local pathways are usually built against.^[3]

Pelvic fracture patients in the United Kingdom have more intensive care admissions and significantly longer hospital stays than any other major trauma patients (15 days versus 8 days).^[2] Mortality during hospital admission is 7.3%, and 14.2% at three months after injury.^[2] Polytrauma patients with bleeding pelvic fractures and severe associated injuries in Japan had a mortality of 46%.^[2]

Independent predictors of death are age, physiological derangement, and associated head, chest and abdominal injuries.^[2] Serious to unsurvivable chest injury (21.2%) and head injury (16.9%) are the leading concomitant injuries, followed by liver or spleen injury (8.0%), two or more long-bone fractures (7.8%) and urogenital injury (3.7%).^[2]

There has been a 398% increase in the yearly incidence of osteoporotic pelvic fractures in older patients from 1970 to 2013.^[2]

In road traffic accidents, risk factors for pelvic fracture include failure of airbag deployment, smaller vehicle size and a lateral deformation point of impact.^[2] In older adults, increasing age, smoking, low bone mass and a tendency to fall are the risk factors.^[2]

Pelvic fractures are frequently part of polytrauma. The constant is energy transferred to the ring: rapid deceleration in the young, a low fall in the frail. Where the mechanism is unclear in an older patient with pain and immobility, think of an insufficiency fracture of the sacrum or pubis rather than only a hip fracture.

The pelvis is a richly vascular ring. When it breaks and opens, the torn vessels and the cancellous bone ooze into a large potential space, the retroperitoneum. The ring also holds a large volume of blood by itself. Three mechanisms feed the bleed:

1. Arterial injury, most often branches of the internal iliac artery (the superior and inferior gluteal, internal pudendal and obturator arteries). Arterial bleeding is under high pressure and is the cause of haemorrhagic shock in the sickest patients.
2. Venous plexus tearing, particularly around the sacroiliac joints. Venous bleeding is commoner but lower pressure.
3. Fracture surfaces of cancellous bone oozing.

The pelvis is part of a wider cavity: bleeding from a pelvic fracture accumulates in the retroperitoneum and can be missed early. The patient then dies of exsanguination within the first 6 hours; head injury dominates from 6 to 24 hours and multiple organ dysfunction thereafter.^[2]

An intact pelvic binder reduces the ring volume, stabilises the fracture and prevents disruption of formed clots. That is why it is applied before transfer and before imaging, at the level of the greater trochanters.^[2]

Suspicion comes from mechanism and from signs:

• inability to bear weight or walk;
• pelvic, groin or low back pain;
• deformity, shortening or rotation of a leg;
• perineal or scrotal bruising (Destot sign), suprapubic bruising (Grey Turner sign), or a high-riding prostate;
• blood at the urethral meatus, haematuria, or vaginal bleeding;
• neurological deficit in the lower limbs or perineum.

In an alert patient, pain on attempted hip movement, especially passive internal rotation or axial loading of the leg, raises suspicion. Hypotension, tachycardia, cold peripheries and a rising lactate after trauma are signs of haemorrhage until proved otherwise.

The pelvic squeeze test (springing the pelvis) is not recommended. It does not reliably predict pelvic fracture and may cause further bleeding by disrupting a freshly formed clot.^[2] Inspect instead: look at the pelvis and perineum, palpate gently over bony landmarks, and check the urethra and vagina. Rectal examination is part of the assessment when urethral or pelvic-floor injury is suspected. ^[1]

Blood tests: full blood count, coagulation studies, liver and renal function, blood group and cross-match, plus venous lactate. Urogenital injuries occur in 3.7% of pelvic fracture patients, urethral injuries in 1.6 to 25%. One gentle attempt at urethral catheterisation is acceptable; if blood-stained urine is found, perform a retrograde cystogram.^[2]

Imaging follows mechanism and haemodynamics. A pelvic X-ray in the resuscitation room is a rapid screen. Computed tomography with intravenous contrast is the definitive study for the ring, the sacrum and the source of bleeding, and CT angiography maps the injured vessel. Polytrauma patients should have an X-ray after binder removal, even with a negative CT, because binders can mask significant pelvic ring ligamentous injuries.^[2]

The initial management follows ATLS ABCDE principles: Airway, Breathing, Circulation, Disability, Exposure.^[2] Circulation is where pelvic fracture care lives. The sequence is:

The key rescue point is the source of bleeding. If the patient does not need an emergency laparotomy for an abdominal injury, first-line treatment is interventional radiology with selective embolisation of the bleeding arterial vessels. If a laparotomy is required, it is done with the pelvic binder in place and haemostasis is achieved by intraoperative pelvic packing.^[2]

The binder itself is removed once the fracture is confirmed mechanically stable, if it fails to control stability, or after haemostasis. Every binder should be removed within 24 hours to prevent pressure sores.^[2] Prophylactic intravenous antibiotics should be given within one hour of injury for open pelvic fractures.^[2]

Massive bleeding also needs a massive transfusion protocol, tranexamic acid and calcium, plus correction of coagulopathy, which the major trauma centre will run in parallel. The review that summarises this field notes that open pelvic and femoral fractures need prophylactic antibiotics within one hour, and that neutropenic fever-style thinking does not apply; the correct reference is the major trauma guideline your centre uses. Route through ATLS.

External fixation is a rapid, damage-control method used in the unstable or shocked patient: it reduces pelvic volume and limits further movement while resuscitation continues. Skeletal traction may be used for vertical shear patterns to restore length.

Definitive pelvic ring reconstruction should be carried out within 72 hours of the patient being physiologically stable, if associated injuries allow.^[2] Screws can be misplaced in up to 11% of patients, and deep postoperative wound infection occurs in 2.9% of those requiring operative fixation, with higher risk after pre-operative angio-embolisation or with a body mass index over 30.^[2]

• Urogenital injury: occurs in 3.7% overall; urethral injuries in 1.6 to 25%.^[2]
• Deep venous thrombosis and pulmonary embolism: reported as 10% and 5% in surgically managed pelvic and acetabular fractures.^[2]
• Chronic pain: 64% of pelvic ring fracture patients report chronic post-traumatic pelvic pain, even 52 months after injury.^[2]
• Sexual dysfunction: up to 43.8% of females and 52.1% of males.^[2]
• Reproductive sequelae: women who have had operative pelvic fracture repair are three times more likely to need further surgery for stress urinary incontinence than the general population.^[2]
• Neurological deficit from lumbosacral plexus injury can be missed in the shocked patient.

Thromboprophylaxis should be initiated according to local guidelines; one cited recommendation is anticoagulation within 24 hours of injury or once haemodynamic stability is achieved.^[2]

Mortality is front-loaded: 7.3% during admission, 14.2% by 3 months.^[2] Death in the first 6 hours is from haemorrhage, from 6 to 24 hours from head injury, and later from multiple organ dysfunction.^[2] Young high-energy injuries and elderly low-energy fractures are two different patient groups with different mortality profiles, but the risk factors for death (age, physiological derangement and associated injuries) apply across the spectrum.

A hip fracture is a fracture of the proximal femur. It is classified by its relation to the joint capsule:

• Intracapsular: femoral neck (subcapital, midcervical, basicervical), which can interrupt the tenuous blood supply to the femoral head. Displaced intracapsular fractures are about half of all hip fractures.^[4]
• Extracapsular: trochanteric (intertrochanteric) and subtrochanteric. Basicervical fractures are uncommon, at 1.8% of cases, and may be treated with either a cephalomedullary nail or a dynamic hip screw.^[4]

Three classification systems dominate the femoral neck: Garden (I incomplete or impacted; II complete without displacement; III complete with partial displacement; IV complete with full displacement), Pauwels (type I fracture line up to 30 degrees to the horizontal, type II 30 to 50 degrees, type III over 50 degrees) and the AO classification.^[4]

Clinical anatomy explains the treatment: displaced intracapsular fractures occur where the femoral blood supply is tenuous, so the femoral head is at risk of avascular necrosis.

Hip fractures are a leading cause of hospitalisation in older adults. There were 1.31 million hip fractures worldwide in 1990, predicted to rise to 6.26 million by 2050.^[4] In the United Kingdom National Hip Fracture Database, 91.6% of hip fractures occur in patients over 70 and 72% are women.^[4] About 30% of patients die within the first year after injury, and only 40 to 60% return to their pre-injury level of mobility and ability within a year.^[4]

Patients over 80, or over 70 with common elderly multimorbidity, are defined as geriatric, and 25 to 50% of patients over 85 are frail.^[4] One in three people over 65 fall each year.^[4]

The dominant mechanism is a low-energy fall in an older person with osteoporosis. Modifiable factors: syncope-related disease, Parkinson disease, polypharmacy, poor vision and footwear, and environmental hazards. Syncope, Parkinson disease and polypharmacy are specifically associated with an increased risk of falling in older adults.^[4]

Fragility is the other half: osteoporosis of the proximal femur plus neuromuscular risk. This is why falls prevention, bone health and vision screening are part of the package and not an afterthought.

The femoral head receives most of its blood from the retinacular branches of the medial circumflex femoral artery, which run along the neck. A displaced femoral neck fracture (Garden III or IV) tears these vessels, and the head becomes avascular. That is why, following the Pauwels classification, internal fixation is indicated in type I or II, while in Garden type III or IV osteosynthesis is generally not recommended; arthroplasty replaces the dead or threatened head instead.^[4]

Displaced intracapsular fractures are roughly half of all hip fractures and occur in a region where the blood supply is tenuous.^[4]

The patient reports hip pain and inability to bear weight, with the affected leg shortened and externally rotated.^[4] In an extracapsular fracture the leg is often more markedly shortened and externally rotated; an impacted or undisplaced intracapsular fracture can be deceptively comfortable and weight-bearing at first.

History must include the mechanism, any blackout or palpitations suggesting syncope, anticoagulants or antiplatelet agents (40% of elderly patients take them), and pre-fracture mobility and cognition, which drive the choice of operation and destination after discharge.^[4]

Plain radiographs are adequate for diagnosis. Anteroposterior and lateral hip films usually show the fracture; an internal rotation view may help. When radiographs are apparently normal but the clinical picture suggests a hip fracture, the fracture is occult and further imaging is needed.^[4]

NICE recommends offering MRI if hip fracture is suspected despite negative X-rays of an adequate standard, and if MRI is not available within 24 hours or is contraindicated, considering CT.^[1]

Other tests:

• blood tests including haemoglobin, urea and electrolytes, glucose, coagulation and group and save;
• ECG, because arrhythmia and ischaemia are both comorbidities and precipitants in a fall;
• cognitive screening: delirium can be present at admission and often remains undiagnosed. The 4AT is validated for hip fracture patients and can be used to assess mental status changes.^[4]

Surgical delay to correct comorbidities is allowed only for conditions that can be corrected: anaemia, anticoagulation, volume depletion, electrolyte imbalance, uncontrolled diabetes, uncontrolled heart failure, correctable cardiac arrhythmia or ischaemia, acute chest infection and exacerbation of chronic chest conditions.^[1]

NICE recommends performing surgery on the day of, or the day after, admission.^[1] The proximal femoral fracture review agrees: surgical management should take place within the first 24 hours beyond which peri-operative complications such as pulmonary embolism, pneumonia, deep vein thrombosis and urinary tract infection increase. If surgery is delayed more than 48 hours, mortality may rise significantly; if performed within 48 hours, a 20% lower risk of dying during the following year has been reported.^[4]

Non-operative management in a patient with multiple comorbidities over 70 gives an 83% risk of secondary displacement if managed non-surgically.^[4]

The aim of operation is full weight-bearing without restriction immediately postoperatively.^[1]

Hemiarthroplasty, replacing only the femoral head, is the treatment of choice for displaced intracapsular fractures in most series, and current evidence supports cement. Pressurising cement increases the risk of bone cement implantation syndrome, which is rare, while evidence highlights reduction in pain and better mobility compared with uncemented implants. Periprosthetic femoral fracture risk is two times higher in patients over 60 with uncemented stems.^[4] Hemiarthroplasty can be associated with a higher dislocation rate than fixation; total hip replacement trades a longer operation and higher dislocation for a better functional score in fit patients.^[4] A multicentre randomised trial found no difference in secondary interventions between total hip replacement and hemiarthroplasty, but a better WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) score favoured total hip replacement.^[4]

Use cemented implants in arthroplasty.^[1][4]

Analgesia. Assess pain immediately on presentation, within 30 minutes of initial analgesia, and hourly until settled on the ward, then regularly thereafter.^[1] Offer paracetamol every 6 hours preoperatively and postoperatively unless contraindicated. Non-steroidal anti-inflammatory drugs are not recommended.^[1][4] Add opioids if necessary. Patients are often elderly and dehydrated, and a flow rate of 100 to 200 mL per hour of isotonic crystalloids is estimated to be safe.^[4]

Anticoagulation. Forty percent of elderly patients with hip fractures take anticoagulants or antiplatelets. If double antiplatelet therapy is in use, spinal anaesthesia is contraindicated. With warfarin, a PT-INR below 1.5 is acceptable; if it is higher, vitamin K is used to reverse. With anti-Xa agents, a plasma drug level under 50 pg/mL is deemed safe for surgery, and if the level cannot be measured a 24-hour gap between the last dose and surgery should be considered. The recommendation for patients on antiplatelet therapy is to proceed without delay.^[4]

Anaesthesia and thromboprophylaxis. Early mobilisation, mechanical thromboprophylaxis and pharmacological prophylaxis with low-molecular-weight heparin for 28 to 35 days, plus physiotherapy, are the standard postoperative bundle. Optimal coordination with anaesthetists is mandatory.^[4]

Tranexamic acid. Systemic tranexamic acid reduces blood loss and transfusion rates, but a recent meta-analysis could not settle the optimal regimen, timing or dose, so follow local protocol.^[4]

Nutrition. Moderate evidence supports dietary supplementation, improving postoperative nutritional status and decreasing mortality.^[4]

NICE specifies a Hip Fracture Programme that integrates surgery with medicine for older people. Its elements are:^[1]

• orthogeriatric assessment;
• rapid optimisation of fitness for surgery;
• early identification of individual goals for multidisciplinary rehabilitation, to recover mobility and independence and to facilitate return to the pre-fracture residence and long-term wellbeing;
• continued coordinated orthogeriatric and multidisciplinary review;
• liaison with related services, particularly mental health, falls prevention, bone health, primary care and social services;
• clinical and service governance responsibility for every stage of the pathway, including care delivered in the community.

The programme delivers care that minimises delirium and maximises independence by active screening for cognitive impairment at presentation, reassessment during admission, and individualised care in line with the NICE delirium guideline.^[1] Early supported discharge is offered when the patient is medically stable, mentally able to participate in continued rehabilitation, and able to transfer and mobilise short distances but has not yet reached full rehabilitation potential.^[1]

Essential peri-operative aspects are pain management, early mobilisation, fluid management, and delirium prevention.^[4] Physiotherapy assessment and, unless medically or surgically contraindicated, mobilisation on the day after surgery are recommended, with mobilisation at least once a day and regular physiotherapy review.^[1] Interdisciplinary orthogeriatric treatment reduces length of stay, complications and mortality.^[4]

Older or frail orthopaedic trauma patients are a named group in the BOA standards programme, and the standard for their care (May 2019) complements the NICE pathway.^[3]

• Death: about 30% within one year.^[4]
• Failure to regain function: only 40 to 60% return to pre-injury mobility within a year.^[4]
• Delirium: common, often missed at admission.^[4]
• Thromboembolism: DVT and PE despite prophylaxis.
• Infection: wound and prosthetic joint infection.
• Periprosthetic fracture: higher risk with uncemented stems in patients over 60.^[4]
• Avascular necrosis: after head-preserving fixation of intracapsular fractures.
• Dislocation: higher after total hip replacement and in patients with cognitive impairment.
• Pressure sores from immobility before or after surgery.
• New fragility fractures if bone health is not addressed.

The figures are sobering and are why surgery, early mobilisation and orthogeriatric care matter: about 30% die within a year, and only 40 to 60% of survivors regain their pre-injury mobility and independence. Operate early, aim for full weight-bearing, and treat the patient, not only the fracture.

The operation does not reverse osteoporosis. Assessment of falls and bone health, and treatment of osteoporosis, reduce the risk of the next fracture, which is the one that kills.

NICE recommends that patients and carers receive verbal and printed information covering diagnosis, choice of anaesthesia, choice of analgesia and other medications, the surgical procedure, possible complications, postoperative care, the rehabilitation programme, long-term outcomes and the professionals involved.^[1]

For pelvic fracture, the x-ray and CT findings should be explained, including the need for a binder and the possibility of further surgery or interventional radiology, and the risk of chronic pain and sexual dysfunction discussed once the patient is stable.

• Pelvic ring injury. A binder is cheap and its application at the greater trochanters is the single most useful pre-hospital step. Plain pelvic X-ray, experienced clinical assessment and transfer to a centre that can pack or embolise are the realistic options. Where interventional radiology is unavailable, pelvic packing in theatre is the fallback. Springing the pelvis is never justified.^[2]
• Hip fracture. Plain X-ray is usually enough; where MRI for occult fracture is unavailable, CT or clinical follow-up is used though occult fractures may be missed. Hemiarthroplasty with a cemented stem is feasible in smaller hospitals; where surgery is delayed because of a lack of theatre or implants, the mortality penalty is real. 4AT screening and basic falls prevention do not require specialist kit. Tranexamic acid, parenteral fluids, paracetamol and low-molecular-weight heparin are inexpensive.
• Across both. Early mobilisation, pressure-area care, thromboprophylaxis and nutrition cost little and change outcomes. Where an orthogeriatrician is not available, one clinician should own the pathway.

• Initial trauma assessment and primary survey
• Damage control surgery and abdominal compartment
• Haemorrhage control in trauma and massive transfusion
• Long bone fractures, fat embolism and dislocations
• Perioperative care
• Osteoporosis and fragility fractures (when available)
• Delirium in hospital