Introduction

The incidence of hip fractures in the United States is over 250,000 hospitalizations per year with approximately half the cases in the pertrochanteric/subtrochanteric group, and femoral neck and head fractures accounting for the remainder.

Ninety-five percent of hip fractures occur in people older than 65 years. Lifetime incidence of hip fracture is 20% for women and 10% for men. Males have three times higher risk of death compared to females.

I. Preoperative

1. 
   

   History and physical examination

   
   
   
   
   1. 
      

      The presenting complaint is pain about the groin or hip with possible radiation to the knee and inability to ambulate or bear weight on the affected leg.

      
      
   2. 
      

      Mechanism of injury—ground level fall (elderly patients) or high-energy trauma (typically younger patients).

      
      
   3. 
      

      Past history may include an osteoporosis diagnosis, previous contralateral hip or other fragility fracture, and prior bisphosphonate therapy.

      
      
   4. 
      

      Physical findings may consist of lower extremity deformity with external rotation and shortening, bruising of the lateral proximal thigh or buttocks, and the inability to lift the affected leg off the stretcher with pain.

      
      
   5. 
      

      Auscultation test is a helpful screening tool. Percuss both patellae with the stethoscope bell overlying the symphysis pubis. A difference in sound or pitch between extremities implies a fracture defect between femur and pelvis resulting in impedance of percussive conduction.

      
      
   6. 
      

      Do not manipulate the extremity until after evaluation of radiographic examination if the extremity is deformed or auscultation test is positive.

   
   
2. 
   

   Anatomy

   
   
   
   
   1. 
      

      The pertrochanteric–subtrochanteric hip originates from the extracapsular femoral neck extending to the proximal one-third of the femoral diaphysis (~5 cm below the lesser trochanter).

      
      
   2. 
      

      Components of the hip fracture include the following:

      
      
      
      
      1. 
         

         Pertrochanteric metaphyseal primary fracture line.

         
         
      2. 
         

         Femoral head and intracapsular neck fragment.

         
         
      3. 
         

         Greater trochanter and lateral wall.

         
         
      4. 
         

         Lesser trochanter.

         
         
      5. 
         

         Subtrochanteric diaphysis (origin of the intramedullary canal).

      
      
   3. 
      

      The proximal femur is NOT SOLID. It is composed of a cortical shell adjacent to and covering an internal trabecular cancellous bone network extending from the head through the femoral neck and terminating in the thickened cortical tubular diaphysis below the lesser trochanter (▶ Fig. 34.1a, b ). The two primary trabecular arcade patterns are dense cancellous bone columns that are formed in response to load transfer from standing and sitting. Loss of these arcades predisposes to weakening of the hip structure and propensity to fracture (▶ Fig. 34.2 ).

      

      

      
      
      
      
      1. 
         

         Posteromedial corticocancellous trabecular column (calcar).

         
         
      2. 
         

         Anterolateral corticocancellous trabecular column.

      
      
   4. 
      

      The femoral neck shaft angle averages 128 to 132 degrees on the anteroposterior (AP) view and the femoral head and neck are oriented in 0 to 30 degrees of anteversion (average 15 degrees) in relation to the coronal plane of the femur in most adults. Appreciation of these orientations is important in reduction and fixation tactics.

      
      
   5. 
      

      Neurologic and vascular structures are rarely at risk from these fractures.

      
      
   6. 
      

      Local preexisting disease, from osseous deformity, soft-tissue contractures, arthropathy, and microarchitecture pathology (osteomalacia and osteoporosis), may affect the surgical tactics and prognosis.

   
   
3. 
   

   Diagnostic imaging

   
   
   
   
   1. 
      

      Plain film radiographs are the mainstay of diagnosis.

      
      
      
      
      1. 
         

         AP pelvis including hips (compare to normal side).

         
         
      2. 
         

         AP hip and cross-table lateral hip views.

         
         
      3. 
         

         Traction internal rotation AP view may be helpful in understanding fracture pattern, especially if shortened or excessively rotated on presentation.

      
      
   2. 
      

      CT scans may be useful for multiplanar fractures from high-energy trauma.

      
      
   3. 
      

      MRI scan most useful for diagnosis of occult fractures of the hip.

   
   
4. 
   

   Classification of hip fractures

   
   
   
   
   1. 
      

      AP and lateral view radiographic images are used to classify the fracture to give insight into fixation tactics and implant selection. They also relate to complexity of the reduction and the loads imparted to the implant.

      
      
   2. 
      

      Common classifications for pertrochanteric and subtrochanteric hip fractures (▶ Table 34.1 ).

      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      

      Table 34.1 Common classifications for pertrochanteric and subtrochanteric hip fractures

      Name	Year	Class	Note
      Boyd and Griffin	1934	1. Stable two-part 2. Unstable posteromedial comminution 3. Subtrochanteric extension laterally and reverse obliquity 4. Subtrochanteric/intertrochanteric multiplanar	Correlated implant failure rate increases from classes 1 to 4 with plate fixation
      OTA/AO 31A	2018	A1: Simple pertrochanteric fracture with intact lateral wall A2: Incompetent lateral wall A3: Reverse obliquity or transverse pattern	AP radiograph only
      Russell and Taylor	1988	1A: GT intact: LT intact 1B: GT intact: LT unstable 2A: GT unstable: LT intact 2B: GT unstable: LT unstable	Subtrochanteric classification relates optimal stability from interlocking nail vs. CMN vs. plate/screw
      Abbreviations: AP, anteroposterior; CMN, cephalomedullary nail; GT, greater trochanteric region including lateral wall; LT, lesser trochanter and adjacent wall.

      
      
   3. 
      

      AO/OTA Fracture and Dislocation Classification Compendium-2018 is an alphanumeric classification most commonly used for pertrochanteric fractures. Proximal metaphyseal fractures of the hip are grouped into the 31A category (▶ Fig. 34.3a–c ).

      

      
      
      
      
      1. 
         

         31A1 fractures are intertrochanteric fractures with an intact lateral wall (wall thickness > 20.5 mm). A stable reduction should be obtainable. Sliding hip screw (SHS) plates and cephalomedullary nails (CMNs) are equally effective.

         
         
      2. 
         

         31A2 fractures are multifragmentary intertrochanteric fractures with an incompetent lateral wall (wall thickness of ≤ 20.5 mm). These fractures are unstable and typically treated with a CMN. Alternative implants include SHS with a trochanteric buttress plate, blade plate, and locking plate.

         
         
      3. 
         

         31A3 intertrochanteric fractures are unstable with standard SHS plating due to reverse obliquity patterns and subtrochanteric extension in this group. CMNs are commonly recommended.

      
      
   4. 
      

      The Russell–Taylor Classification for subtrochanteric fractures (1988) relates the consideration of implant selection based on involvement of the greater and lesser trochanteric components in proximal femur fractures (▶ Fig. 34.4 ).

      

      
      
      
      
      1. 
         

         Fractures below the lesser trochanter and not involving the greater trochanter and lateral wall (type IA) can be treated with conventional static interlocking nails ( Fig. 34.4a ).

         
         
      2. 
         

         For fractures of the lesser trochanter and the medial column, but intact greater trochanteric region (type IB), the implant requires increased structural design strength such as a CMN (▶ Fig. 34.4b ).

         
         
      3. 
         

         Type II fractures relate to greater trochanteric region and piriformis fossa involvement.

         
         
      4. 
         

         If the greater trochanteric fragment is stable and there is no lesser trochanteric fracture comminution (type IIA), a trochanteric portal CMN is commonly used (▶ Fig. 34.4c ).

         
         
      5. 
         

         In type IIB fractures, the greater trochanteric lateral wall complex is unstable and there is medial comminution of the lesser trochanteric region (▶ Fig. 34.4d ).

         
         
         
         
         • 
           

           i. This is the most unstable type of fracture and open reduction with the use of trochanteric buttress type lateral plates with ancillary fixation may be required.

           
           
         • 
           

           ii. Alternatively, CMNs are commonly used for this fracture pattern; however, several challenges exist: nails can be difficult to use in this class of fracture, as the split in the proximal fracture does not permit stable containment of the nail in the proximal femur.

      
      
   5. 
      

      Intraoperative change in classification may occur resulting in a tactical change:

      
      
      
      
      1. 
         

         Lateral wall failure during plate application occurs up to 74% intraoperatively and may necessitate change to trochanteric buttress addition or CMN.

         
         
      2. 
         

         Subtrochanteric extension below the lesser trochanter during surgery necessitates change to trochanteric extension and longer plates or conversion to longer nail if short nail was the original plan.