Intertrochanteric Fractures

DR.MANNAN AHMED

• The incidence of intertrochanteric fractures is gender- and race-dependent and varies from country to Country.

• Some of the factors found to be associated with a patient sustaining an intertrochanteric rather than a femoral neck fracture include advancing age, increased number of comorbidities, increased dependency in activities of daily living, and a history of other osteoporosis related fractures.

Mechanism of Injury

• Intertrochanteric fractures in younger individuals are usually the result of a high-energy injury, such as a motor vehicle accident (MVA) or fall from a height.

• Ninety percent of intertochanteric fractures in the elderly result from a simple fall. The tendency to fall increases with patient age and is exacerbated by several factors, including poor vision, decreased muscle power, labile blood pressure, decreased reflexes, vascular disease, and coexisting musculoskeletal pathology.

According to Cummings (4),four factors contribute to determining whether a particular fall results in a fracture of the hip

• (a) Fall must be oriented so the person lands on or near the hip

• (b) protective reflexes must be inadequate to reduce the energy of the fall below a certain critical threshold,

• (c) local shock absorbers (muscle and fat around the hip) must be inadequate.

• (d) bone strength at the hip must be insufficient.

Signs and Symptoms

• The clinical presentation of patients who have sustained an intertochanteric fracture can vary widely depending on type, severity, and etiology.

• Displaced fractures are clearly symptomatic, such patients usually cannot stand, much less ambulate.

• nondisplaced fractures may be ambulatory and experience minimal pain, and there are yet others who complain of thigh or groin pain but have no history of antecedent trauma.

Physical Examination

• The amount of clinical deformity in patients with an intertrochanteric fracture reflects the degree of fracture displacement.

• Patients with a nondisplaced fracture may present with a virtual absence of clinical deformity, those with a displaced fracture exhibit the classic presentation of a shortened and externally rotated extremity. There may be tenderness to palpation in the area of the greater trochanter, Range-of-motion testing of the hip is usually painful and should be avoided.

Associated Injuries

Older individuals who sustain an intertrochanteric fracture as a result of a low-energy fall occasionally have an associated osteoporosis related fracture, such as a distal radius or proximal humerus fracture.

• Intertrochanteric fractures in younger individuals are usually the result of a high-energy injury, such as a motor vehicle accident or fall from a height. In these instances, assessment must be made of possible associated head, neck, chest, and abdominal injuries.

• X-Rays and Other Imaging Studies

1.(AP) view of the pelvis .2.AP and a cross-table lateral view of the involved proximal femur

When a hip fracture is suspected but not apparent on standard x-rays, a technetium bone scan or a magnetic resonance imaging (MRI) scan should be obtained. MRI has been shown to be at least as accurate as bone scanning in identification of occult fractures of the hip, and it will reveal a fracture within 24 hours of injury.

Evans classification

• Type1—two part undisplaced.• Type2-- two part displaced.• Type3—three fragment fracture without

posterolateral support (displaced GT Fragment).• Type 4-- three fragment fracture without medial

support( displaced LT Fragment).• Type 5—four fragment fracture without

posterolateral and posteromedial support.• Type 6—reverse oblique fracture.

Orthopaedic Trauma Association (OTA) Alphanumeric Fracture Classification

• Group 1 fractures are simple (two-part) fractures, with the typical oblique fracture line extending from the greater trochanter to the medial cortex; the lateral cortex of the greater trochanter remains intact.

• Group 2 fractures are comminuted with a postero-medial fragment; the lateral cortex of the greater trochanter, however, remains intact. Fractures in this group are generally unstable, depending on the size of the medial fragment.

• Group 3 fractures are those in which the fracture line extends across both the medial and lateral cortices; this group also includes the reverse obliquity pattern.

CURRENT TREATMENT OPTIONS

• Nonoperative Treatment• Before the introduction of suitable fixation

devices in the 1960s, treatment for intertrochanteric fractures was of necessity nonoperative, consisting of prolonged bedrest in traction until fracture healing occurred (usually 10 to 12 weeks), followed by a lengthy program of ambulation training.

• In elderly patients, this approach was associated with high complication rates; typical problems included decubiti, urinary tract infection, joint contractures, pneumonia, and thromboembolic complications, resulting in a high mortality rate. In addition, fracture healing was generally accompanied by varus deformity and shortening because of the inability of traction to effectively counteract the deforming muscular forces.

• Indications for Nonoperative Treatment• 1.An elderly person whose medical condition

carries an excessively high risk of mortality from anesthesia and surgery.

• 2.Nonambulatory patient who has minimal discomfort following fracture

Operative Treatment

fixed-angle nail-plate devices• The first successful implants were fixed-angle

nail-plate devices (e.g., Jewett nail, Holt nail) consisting of a triflanged nail fixed to a plate at an angle of 130 to 150 degrees, While these devices provided stabilization of the femoral head and neck fragment to the femoral shaft, they did not allow fracture impaction.

Jewett nail, Holt nail consisting of a tri-flanged nail fixed to a plate at an angle of 130 to 150◦

sliding nail-plate devices• The experience with fixed-angle nail-plate

devices indicated the need for a device that would allow controlled fracture impaction. This gave rise to sliding nail-plate devices (e.g., Massie nail, Ken-Pugh nail),

Massie nail ,Ken-Pugh nail consisting of a nail that provided proximal fragment fixation and a side plate that allowed the nail to “telescope” within a barrel allowing bone on bone contact

The sliding nail-plate devices gave rise to sliding hip screw devices.

• The sliding hip screw is the most widely used implant for stabilization of both stable and unstable intertrochanteric fractures. Sliding hip screw side plate angles are available in 5 degree increments from130 to 150 degrees. The 135 degree plate is most commonly utilized; this angle is easier to insert in the desired central position of the femoral head and neck than higher angle devices and creates less of astress riser in the subtrochanteric region.

• Variations on the sliding hip screw's basic design include the variable angle hip screw (VHS) , Talon compression hip screw, greater trochanteric stabilizing plates, the Medoff plate, and the percutaneous compression plate (PCCP).

Talon compression hip screw utilizes a lag screw designed toresist pull out though the femoral head.

• The Talon compression hip screw system incorporates a series of four prongs that protrude from the base of the threads of the lag screw The prongs are designed to engage the cortical bone at the inferior aspect of the femoral neck; this construct theoretically:

• (a)increases the pull out strength of the lag screw from the femoral head and neck fragment,

• (b) provides better rotational stability of the femoral head around the lag screw.

Talon compression hip screw

• A laboratory study comparing use of the Talon hip screw system reported that use of the prongs increased the peak compressive forces generated by Talon device only when the lag screw was inserted in the inferior aspect of the femoral neck and head

Trochanteric stabilizing plates

• The trochanteric stabilizing plate and the lateral buttress plate are modular components that buttress the greater trochanter.These plates are placed over a four-hole sideplate and are used to prevent excessive slide (and resulting deformity) in unstable fracture patterns. These devices prevent telescoping of the lag screw within the plate barrel when the proximal head and neck fragment abuts the lateral buttress plate.

Can be used for screw fixation of the greate trochanter or for insertion of an anti-rotation screw

• Clinical studies suggest that these lateral support plates are most useful with unstable peritrochanteric fractures with a deficient lateral cortical buttress

The Medoff plate- biaxial sliding hip screw

• It has a standard lag screw component for compression along the femoral neck. In place of the standard femoral sideplate, however, it utilizes a coupled pair of sliding components that enable the fracture to impact parallel to the longitudinal axis of the femur.

• A locking set screw may be used to prevent independent sliding of the lag screw within the plate barrel; if the locking set screw is applied, the plate can only slide axially on the femoral shaft (uniaxial dynamization). If, however, the surgeon applies the implant without placement of the locking set screw, sliding may occur along both the femoral neck and the femoral shaft (biaxial dynamization). For most intertrochanteric fractures, biaxial dynamization is suggested.

Two lag screws these two lagscrew components provide greater rotational stability of the proximalfracture fragment.

Barrel component

Use of the PCCP was associated with shorter operative times, less blood loss, and need for fewer number of blood transfusions. No differences were found with respect to fracture union or functional outcomes, a learning curve exists with large variations in operative time compared with a standard sliding hip screw.

Percutanious compression plate

Intramedullary Devices

• When sliding hip screw for stabilsation of I/T #, there has been dissatisfaction with the resultant deformity associated with use of this type of device to stabilize unstable fracture(subtrochentric and reverse oblique) patterns. Excessive sliding of the lag screw within the plate barrel results in limb shortening and medialization (7 time more failure rate) of the distal fragment.

Dissatisfaction with use of a sliding hip screw in unstable fracture patterns

led to the development of intramedullary hip screw devices.

Advantages:• (a) an intramedullary fixation device, because of its location,

theoretically provides more efficient load transfer than does a sliding hip screw.

• (b) the shorter lever arm of the intramedullary device can be expected to decrease tensile strain on the implant, thereby decreasing the risk of implant failure.

• (c) because the intramedullary fixation device incorporates a sliding hip screw, the advantage of controlled fracture impaction is maintained,

• shorter operative time and less soft-tissue dissection than a sliding hip screw.

proximal femoral nail (PFN)

GAMMA NAIL

• The PFN nail has been shown to prevent the fractures of the femoral shaft by having a smaller distal shaft diameter which reduces stress concentration at the tip.

• Due to its position close to the weight-bearing axis the stress generated on the intramedullary implants is negligible.

• PFN implant also acts as a buttress in preventing the medialisation of the shaft. The entry portal of the PFN through the trochanter limits the surgical insult to the tendinous hip abductor musculature only , unlike those nails which require entry through the pyriformis fossa

The main principle of this type of fixation is based on a sliding screw in the femoral neck-head fragment, attached to an intramedullary naiL