Femoral Neck Fractures - Trauma (2024)

• common

  • increasingly common due to aging population

• women > men

• Caucasians > African Americans

• United states has highest incidence of hip fx rates worldwide

• healing potential

  • femoral neck is intracapsular, bathed in synovial fluid

  • lacks periosteal layer

  • callus formation limited, which affects healing

• high energy in young patients

• low energy falls in older patients

• femoral shaft fractures

  • 6-9% associated with femoral neck fractures

  • treat femoral neck first followed by shaft

• normal neck shaft-angle 130 +/- 7 degrees

• normal anteversion 10 +/- 7 degrees

Blood supply to femoral head

• major contributor is medial femoral circumflex (lateral epiphyseal artery)

• some contribution to anterior and inferior head from lateral femoral circumflex

• some contribution from inferior gluteal artery

• small and insignificant supply from artery of ligamentum teres

• displacement of femoral neck fracture will disrupt the blood supply and cause an intracapsular hematoma (effect is controversial)

• impacted and stress fractures

  • slight pain in the groin or pain referred along the medial side of the thigh and knee

• displaced fractures

  • pain in the entire hip region

• impacted and stress fractures

  • no obvious clinical deformity

  • minor discomfort with active or passive hip range of motion, muscle spasms at extremes of motion

  • pain with percussion over greater trochanter

• displaced fractures

  • leg in external rotation and abduction, with shortening

• recommended views

  • AP

    • traction-internal rotation AP hip is best for defining fracture type

  • cross-table lateral

  • full-length femur

• optional views

  • consider obtaining dedicated imaging of uninjured hip to use as template intraop

• indications

  • helpful in determining displacement and degree of comminution in some patients

• indications

  • helpful to rule out occult fracture

  • not helpful in reliably assessing viability of femoral head after fracture

    See Also

    Conservative versus surgical treatment for Garden I hip... : MedicineJunkhead Dumpster Service Demolition and Junk Removal - labor / hauling / moving - craigslist

• indications

  • helpful to rule out occult fracture

  • not helpful in reliably assessing viability of femoral head after fracture

• indications

  • rule out DVT if delayed presentation to hospital after hip fracture

• observation alone

  • indications

    • may be considered in some patients who are non-ambulators, have minimal pain, and who are at high risk for surgical intervention

• closed reduction with cannulated screw fixation

  • indications

    • nondisplaced transcervical fx

    • Garden I or II in the physiologically elderly

    • displaced transcervical fx in young patient

      • achieve reduction to limit vascular insult

      • reduction must be anatomic, so open if necessary

• open reduction internal fixation (ORIF)

  • indications

    • displaced fractures in young or physiologically young patients

      • ORIF indicated for most pts <50 years of age

        • female sex associated with increased reoperation rate

  • techniques

    • sliding hip screw

      • indications

        • basicervical fracture

        • vertical fracture pattern in a young patient

          • sliding hip screw biomechanically superior to cannulated screws (may not be clinically superior)

      • consider placement of additional cannulated screw above sliding hip screw to prevent rotation

• hemiarthroplasty

  • indications

    • controversial

    • debilitated elderly patients

    • metabolic bone disease

  • techniques

    • cemented hemiarthroplasty

      • decreased intraoperative and postoperative fracture rates in elderly insufficiency fractures

      • improved short and medium term mobility

• total hip arthoplasty

  • indications

    • controversial

    • older active patients

    • patients with preexisting hip osteoarthritis

      • more predictable pain relief and better functional outcome than hemiarthroplasty

    • Garden III or IV in patient < 85 years

• time to surgery

  • controversial

    • reduction method and quality has more pronounced effect on healing than surgical timing

  • elderly patients with hip fractures should be brought to surgery as soon as medically optimal (preferably <24-48 hours)

    • the benefits of early mobilization cannot be overemphasized

      • improved outcomes in medically fit patients if surgically treated less than 4 days from injury

    • preoperative echocardiograms have been shown to delay the time to surgery without any effect on treatment decisions

• anesthesia type

  • spinal versus general

    • no difference in postoperative delirium, mortality or ambulatory function at 60 days

• treatment approach based on

  • degree of displacement

  • physiologic age of the patient (young is < than 50 years old)

  • ipsilateral femoral neck and shaft fractures

• technique

  • three screws if noncomminuted (3 screw inverted triangle shown to be superior to two screws)

  • order of screw placement (this varies)

    • 1-inferior screw along calcar

    • 2-posterior/superior screw

    • 3-anterior/superior screw

  • obtain as much screw spread as possible in femoral neck

  • inverted triangle along the calcar (not central in the neck) has stronger fixation and higher load to failure

  • four screws considered for posterior comminution

    • clear advantage of additional screws not proven in literature

  • starting point at or above level of lesser trochanter to avoid fracture

  • avoid multiple cortical perforations during guide pin or screw placement to avoid development of lateral stress riser

• approach

  • limited anterior Smith-Peterson

    • 10cm skin incision made beginning just distal to AIIS

    • incise deep fascia

    • develop interval between sartorious and TFL

    • external rotation of thigh accentuates dissection plane

    • LFCN is identified and retracted medially with sartorius

    • identify tendinous portion of rectus femoris, elevate off hip capsule

    • open capsule to identify femoral neck

  • Watson-Jones

    • used to gain improved exposure of lower femoral neck fractures

    • skin incision approx 2cm posterior and distal to ASIS, down toward tip of greater trochanter

    • incision curved distally and extended 10cm along anterior portion of femur

    • incise deep fascia

    • develop interval between TFL and gluteus medius

    • anterior aspect of gluteus medius and minimus is retracted posteriorly to visualize anterior hip capsule

    • capsule sharply incised with Z-shape incision

    • capsulotomy must remain anterior to lesser trochanter at all times to avoid injury to medial femoral circumflex artery

• reduction

  • open versus closed reduction

    • worse outcomes with displacement > 5 mm (higher rate of osteonecrosis and nonunions)

    • no consensus on which reduction approach is superior

    • multiple closed reduction attempts are associated with higher risk of osteonecrosis of the femoral head

  • technique

    • evacuate hematoma

    • place A to P k-wires into femoral neck/head proximal to fracture to use as joysticks for reduction

    • insert starting k-wire (for either cannulated screw or sliding hip screw) into appropriate position laterally, up to but not across the fracture

    • once reduction obtained, drive starting k-wire across fracture

    • insert second threaded tipped k-wire if adding additional fixation

• fixation

  • fixation with implants that allow sliding

    • permit dynamic compression at fx site during axial loading

    • can cause shortening of femoral neck

      • prominent implants

      • affects biomechanics of hip joint

      • lower physical function on SF-36

      • decreased quality of life

    • anatomic reduction with intraop compression and placement of length stable devices decrease shortening

• approach

  • posterior approach has increased risk of dislocations

  • anterolateral approach has increased abductor weakness

• technique

  • cemented superior to uncemented in elderly population (decreased revision rates)

  • unipolar vs. bipolar

• technique

  • should consider using the anterolateral approach and selective use of larger heads in the setting of a femoral neck fracture

• advantages

  • improved functional hip scores and lower re-operation rates compared to hemiarthroplasty and internal fixation

• complications

  • higher rate of dislocation with THA (~ 10%)

    • about five times higher than hemiarthroplasty

• incidence of 10-45%

• recent studies fail to demonstrate an association between time to fracture reduction and subsequent AVN

• increased risk with

  • increase initial displacement

    • AVN can still develop in nondisplaced injuries

  • nonanatomical reduction

  • sliding hip screw

    • reported by the FAITH study

• treatment

  • major symptoms not always present when AVN develops

  • young patient

    • > 50% involvement then treat with FVFG vs THA

  • older patient

    • prosthetic replacement (hemiarthroplasty vs THA)

• incidence of 5 to 30%

  • increased incidence in displaced fractures

  • no correlation between age, gender, and rate of nonunion

• varus malreduction most closely correlates with failure of fixation after reduction and cannulated screw fixation.

• treatment

  • valgus intertrochanteric osteotomy

    • indicated in patients after femoral neck nonunion

      • can be done even in presence of AVN, as long as not severely collapsed

      • turns vertical fx line into horizontal fx line and decreases shear forces across fx line

  • free vascularized fibula graft (FVFG)

    • indicated in young patients with a viable femoral head

  • arthroplasty

    • indicated in older patients or when the femoral head is not viable

    • also an option in younger patient with a nonviable femoral head as opposed to FVFG

  • revision ORIF

• higher rate of dislocation with THA (~ 10%)

  • about seven times higher than hemiarthroplasty

• high early failure rates in fixation group, which stabilizes after 2 years

  • 2-year follow-up (elderly population >70 years) with displaced femoral neck fractures

    • 46% failure with fixation techniques

    • 8% failure with arthroplasty techniques

  • 2-to-10 year follow-up

    • failure rate approx. 2-4%, respectively

• overall failure rates still higher in fixation vs. arthoplasty at 10-year follow-up

• sliding hip screw with lower reoperation rates compared to cannulated screws

  • displaced femoral neck fractures

  • basicervical femoral neck fractures

  • current smokers

Reducing complications with co-management service

• orthopaedic geriatric co-management of trauma patients has been demonstrated to yield

  • decreased mortality, post-operative complications, time to surgery, length of stay (though conflicting results on length of stay)

  • improved post-operative mobility at 4 months

• important to mitigate risks of hospital delirium which may lead to increased length of stay

Loss of independence

• requiring walking aids and assisted living following fracture surgery

  • the timed up and go (TUG) test has been identified as a reliable predictor of a patient's need for post-operative assistive devices

    • Normal TUG is <12 seconds in all age groups

    • Persistent use of ambulatory aids is predicted if TUG > 26 seconds

• associated factors

  • age >80 years

  • ASA class >1

  • prior walking aid use

  • current tobacco use

  • implant placement quality

  • nondisplaced fracture

  • not requiring revision surgery

• ~25-30% at one year (higher than vertebral compression fractures)

• pre-injury mobility is the most significant determinant for post-operative survival

• in patients with chronic renal failure, rates of mortality at 2 years postoperatively, are close to 45%

• mortality risk is decreased at 30 days and at 1 year post-op when surgical intervention is performed within 24 hours of admission