I. Associated with hip dislocations ¹ – ⁴ :

1. 
   

   True orthopaedic emergency.

   
   
2. 
   

   Shear type fractures.

   
   
3. 
   

   Indentation or crush type. ⁵

II. Anatomy and blood supply to the femoral head ⁶ :

1. 
   

   Medial femoral circumflex artery (MFCA).

   
   
2. 
   

   The MFCA branches from the deep femoral artery:

   
   
   
   
   1. 
      

      Five constant branches: superficial, ascending, acetabular, descending, deep.

   
   
3. 
   

   The deep branch supplies the blood to the femoral head:

   
   
   
   
   1. 
      

      Perforates the posterior capsule.

      
      
   2. 
      

      Proximal to the superior gemellus.

      
      
   3. 
      

      Distal to the tendon of the piriformis.

   
   
4. 
   

   Terminates in the posterolateral retinacular branches:

   
   
   
   
   1. 
      

      Covered by synovium.

      
      
   2. 
      

      Enters the femoral head: 2 to 4 mm lateral to the bone–cartilage junction.

   
   
5. 
   

   Anastomosis of the inferior gluteal artery and the MFCA:

   
   
   
   
   1. 
      

      Inferior border of the piriformis.

      
      
   2. 
      

      Constant anastomosis.

      
      
   3. 
      

      Must be preserved with surgical approaches.

I. High-energy motor vehicle collision (84%) ⁷ :

1. 
   

   Posterior hip dislocation:

   
   
   
   
   1. 
      

      Twelve percent are associated with femoral head fractures.

      
      
   2. 
      

      Axial load with hip flexed and adducted.

      
      
   3. 
      

      Knee to dashboard. ⁸

   
   
2. 
   

   Associated injuries in hip dislocation and femoral head fractures:

   
   
   
   
   1. 
      

      Acetabular fracture. ⁸

      
      
   2. 
      

      Femoral neck fracture.

      
      
   3. 
      

      Femoral shaft fracture.

      
      
   4. 
      

      Ipsilateral knee injuries (25%) ⁸ :

      
      
      
      
      1. 
         

         Meniscus tear (22%).

         
         
      2. 
         

         Bone marrow edema (33%).

         
         
      3. 
         

         Knee effusion (37%).

         
         
      4. 
         

         Cruciate ligament injury (25%).

         
         
      5. 
         

         Collateral ligament injury (21%).

         
         
      6. 
         

         Periarticular knee fracture (15%).

      
      
   5. 
      

      Sciatic nerve injury (10–23%) ⁹ – ¹² :

      
      
      
      
      1. 
         

         Peroneal division.

         
         
      2. 
         

         Sixty to 70% recover. ¹³

      
      
   6. 
      

      Pelvis, abdomen, chest, head, and spine injuries.

I. History:

1. 
   

   Limited.

   
   
2. 
   

   High-energy trauma.

II. Physical examination:

1. 
   

   ATLS (Advanced Trauma Life Support):

   
   
   
   
   1. 
      

      Prioritize (life, limb, function).

      
      
   2. 
      

      Primary survey:

      
      
      
      
      1. 
         

         Airway and cervical spine control.

         
         
      2. 
         

         Breathing and ventilation.

         
         
      3. 
         

         Circulation and hemorrhage.

         
         
      4. 
         

         Disability.

         
         
      5. 
         

         Exposure.

      
      
   3. 
      

      Secondary survey:

      
      
      
      
      1. 
         

         History.

         
         
      2. 
         

         Head to toe examination.

         
         
      3. 
         

         Extremity:

         
         
         
         
         • 
           

           i. Posterior dislocation: Hip position ¹⁴ : Flexed, adducted, and internally rotated.

           
           
         • 
           

           ii. Anterior dislocation: Hip position ¹⁵ : abducted, externally rotatated, flexed (inferior or obturator, and extended – superior or pubic), vascular examination. neurologic examination: motor and sensory to lower extremity and always before and after reduction attempts.

III. Imaging:

1. 
   

   Plain radiographs:

   
   
   
   
   1. 
      

      Supine anteroposterior (AP) pelvis:

      
      
      
      
      1. 
         

         Routine imaging in polytrauma.

         
         
      2. 
         

         Symmetric femoral heads.

         
         
      3. 
         

         Femoral head fragment in acetabular fossa.

         
         
      4. 
         

         Femoral neck.

         
         
      5. 
         

         Limb position.

         
         
      6. 
         

         Pelvic ring injury:

         
         
         
         
         • 
           

           i. Inlet and outlet views.

           
           
         • 
           

           ii. CT scan.

         
         
      7. 
         

         Acetabular fractures:

         
         
         
         
         • 
           

           i. Judet’s views (iliac and obturator oblique).

           
           
         • 
           

           ii. CT scan.

      
      
   2. 
      

      Cross-table lateral:

      
      
      
      
      • 
        

        Orthogonal imaging.

   
   
2. 
   

   CT:

   
   
   
   
   1. 
      

      Frequently performed in polytrauma patients:

      
      
      
      
      1. 
         

         Chest, abdomen, pelvis.

         
         
      2. 
         

         Cervical, thoracic, and lumbar spine.

      
      
   2. 
      

      Prereduction CT:

      
      
      
      
      1. 
         

         Should not delay hip reduction.

         
         
      2. 
         

         Indicated in irreducible dislocation.

      
      
   3. 
      

      Postreduction evaluation:

      
      
      
      
      1. 
         

         Always CT scan following closed reduction.

         
         
      2. 
         

         Multicut detector, high-collimation, 1- to 2-mm cuts.

         
         
      3. 
         

         Evaluation:

         
         
         
         
         • 
           

           i. Concentric reduction.

           
           
         • 
           

           ii. Intra-articular loose bodies.

           
           
         • 
           

           iii. Femoral head fracture: size and location.

           
           
         • 
           

           iv. Acetabular fractures:

           
           
           
           
           1. 
              

              Posterior wall fracture.

           
           
         • 
           

           v. Femoral neck.

I. Pipkin ¹⁷ ( Fig. 10.1 ):

1. 
   

   Femoral head fracture with posterior hip dislocations:

   
   
   
   
   1. 
      

      Type I:

      
      
      
      
      1. 
         

         Fracture below the fovea.

         
         
      2. 
         

         Fracture outside the weight-bearing joint area.

      
      
   2. 
      

      Type II:

      
      
      
      
      1. 
         

         Fracture cranial to the fovea.

         
         
      2. 
         

         Fracture within the weight-bearing joint area.

         

      
      
   3. 
      

      Type III:

      
      
      
      
      1. 
         

         Associated ipsilateral femoral neck fracture.

      
      
   4. 
      

      Type IV:

      
      
      
      
      1. 
         

         Associated ipsilateral acetabular fracture.

II. Orthopaedic Trauma Association (OTA):

1. 
   

   31-C, articular fracture head ¹⁸ :

   
   
   
   
   1. 
      

      31-C1, split fracture (Pipkin types I–II):

      
      
   2. 
      

      31-C2, with depression.

      
      
   3. 
      

      31-C3, with femoral neck fracture.

I. Nonoperative ¹⁵ , ¹⁹ :

1. 
   

   Emergent closed reduction.

   
   
2. 
   

   Touchdown weight bearing for 4 weeks.

   
   
3. 
   

   Knee immobilizer or hip abduction brace.

   
   
4. 
   

   Indications:

   
   
   
   
   1. 
      

      Pipkin type I with articular incongruity of 1 mm or less.

      
      
   2. 
      

      Pipkin type II without articular incongruity.

      
      
   3. 
      

      No interposed fragment.

      
      
   4. 
      

      Concentrically reduced joint.

      
      
   5. 
      

      Patients that are unable to tolerate surgery.

II. Surgical treatment:

1. 
   

   Open reduction and internal fixation (ORIF) ¹⁹ :

   
   
   
   
   1. 
      

      Indications:

      
      
      
      
      1. 
         

         Pipkin type I with greater than 1 mm articular incongruity.

         
         
      2. 
         

         Pipkin type II with any displacement.

         
         
      3. 
         

         Pipkin types III and IV.

         
         
      4. 
         

         Interposed fragment.

         
         
      5. 
         

         Nonconcentrically reduced joint.

      
      
   2. 
      

      Surgical approaches:

      
      
      
      
      1. 
         

         Smith–Peterson approach.

         
         
      2. 
         

         Trochanteric flip osteotomy.

         
         
      3. 
         

         Surgical hip dislocation.

         
         
      4. 
         

         Transgluteal approaches.

         
         
      5. 
         

         Arthroscopic-assisted percutaneous fixation.

      
      
   3. 
      

      Method of fixation:

      
      
      
      
      1. 
         

         Mini or small fragment screws ²⁰ :

         
         
         
         
         • 
           

           i. Cancellous biosabsorble.

           
           
         • 
           

           ii. Herbert screw fixation.

           
           
         • 
           

           iii. Countersunk screws.

         
         
      2. 
         

         Pelvis reconstruction plate.

      
      
   4. 
      

      Pipkin type III fractures:

      
      
      
      
      1. 
         

         Femoral head and neck ORIF.

         
         
      2. 
         

         Hip arthroplasty:

         
         
         
         
         • 
           

           i. Elderly.

           
           
         • 
           

           ii. Comminution.

      
      
   5. 
      

      Pipkin type IV:

      
      
      
      
      1. 
         

         Femoral head and acetabulum ORIF.

         
         
      2. 
         

         Restore acetabular stability.

      
      
   6. 
      

      Rehabilitation:

      
      
      
      
      1. 
         

         Immediate mobilization.

         
         
      2. 
         

         Touchdown weight bearing with two crutches:

         
         
         
         
         • 
           

           i. Six to 8 weeks: isolated femoral head fixation.

           
           
         • 
           

           ii. Eight to 12 weeks: femoral neck or acetabulum.

   
   
2. 
   

   Prosthetic replacement ¹⁹ :

   
   
   
   
   1. 
      

      Total hip arthroplasty:

      
      
      
      
      1. 
         

         Active.

         
         
      2. 
         

         Longer life expectancy.

      
      
   2. 
      

      Hemiarthroplasty:

      
      
      
      
      1. 
         

         Older patient.

         
         
      2. 
         

         Limited mobility.

      
      
   3. 
      

      Indications:

      
      
      
      
      1. 
         

         Pipkin type III in the elderly.

         
         
      2. 
         

         Evidence of advanced hip arthritis.

I. Posttraumatic arthritis (20%) ²¹ :

1. 
   

   Osteochondral lesion:

   
   
   
   
   1. 
      

      Larger size.

      
      
   2. 
      

      Weight-bearing location.

      
      
   3. 
      

      Comminution.

   
   
2. 
   

   Acetabulum or femoral head bone loss.

   
   
3. 
   

   Incongruent reduction:

   
   
   
   
   1. 
      

      Soft-tissue interposition.

      
      
   2. 
      

      Incarcerated bone fragment.

II. Avascular necrosis (AVN; 12%) ²² :

1. 
   

   Hip dislocations with associated femoral head fractures:

   
   
   
   
   1. 
      

      High-energy trauma disrupts vascular supply.

      
      
   2. 
      

      Delay in treatment.

      
      
   3. 
      

      Iatrogenic injury:

      
      
      
      
      1. 
         

         Closed reduction.

         
         
      2. 
         

         Surgical approaches:

         
         
         
         
         • 
           

           i. Preferable anterior or trochanteric flip.

III. Heterotopic ossification (6–64%) ⁹ , ¹¹ , ¹² , ²³ – ²⁵ :

1. 
   

   Muscle and soft-tissue injury:

   
   
   
   
   1. 
      

      Mechanism of trauma.

      
      
   2. 
      

      Surgical exposure.

   
   
2. 
   

   Acetabular fracture (Pipkin type IV):

   
   
3. 
   

   Associated head injury.

IV. Malunion. ²⁶

V. Hip instability.

I. Epidemiology:

1. 
   

   Higher in patients older than 70 years. ²⁷

   
   
2. 
   

   Common in the elderly patients.

   
   
3. 
   

   Uncommon in young patients.

   
   
4. 
   

   Osteoporosis major risk factor:

   
   
   
   
   1. 
      

      Risks increases with decreasing bone mass.

      
      
   2. 
      

      More common in women.

      
      
   3. 
      

      Bone density in the proximal femur declines with age.

      
      
   4. 
      

      Low bone mineral density:

      
      
      
      
      1. 
         

         Chronic diseases:

         
         
         
         
         • 
           

           i. Hypothyroidism.

           
           
         • 
           

           ii. Rheumatoid arthritis.

         
         
      2. 
         

         Menopause.

         
         
      3. 
         

         Tobacco use.

         
         
      4. 
         

         Alcohol use.

         
         
      5. 
         

         Medications:

         
         
         
         
         • 
           

           i. Corticosteroids.

           
           
         • 
           

           ii. Seizure medications.

II. Anatomy:

1. 
   

   Osseous ²⁸ , ²⁹ :

   
   
   
   
   1. 
      

      Femoral neck shaft angle is approximately 130 ± 7 degrees.

      
      
   2. 
      

      Femoral neck anteversion is approximately 10 ± 7 degrees.

      
      
   3. 
      

      Femoral head diameter varies between 40 and 60 mm.

   
   
2. 
   

   Vascular ⁶ :

   
   
   
   
   1. 
      

      MFCA:

      
      
      
      
      1. 
         

         Lateral epiphyseal branch.

         
         
      2. 
         

         Main blood supply to the femoral head.

      
      
   2. 
      

      Lateral femoral circumflex:

      
      
      
      
      1. 
         

         Inferior metaphyseal branch.