What is the step by step procedure for a total hip replacement?

Total Hip Replacement: Step-by-Step Surgical Procedure

Total hip replacement is a highly successful surgical procedure involving the replacement of a damaged hip joint with an artificial prosthesis to relieve pain and improve function in patients with advanced arthritis of the hip joint.

Preoperative Preparation

• Comprehensive patient evaluation to confirm indication (typically symptomatic osteoarthritis)
• Appropriate imaging studies (radiographs, possibly CT or MRI)
• Preoperative planning for implant selection and sizing
• Anesthesia preparation (general anesthesia with peripheral nerve block or spinal anesthesia with local anesthetic and opioid) 1
• Patient positioned (typically lateral decubitus or supine)
• Surgical site preparation and draping

Surgical Approach Selection

Several approaches can be used, each with specific advantages:

• Posterior approach: Most common, provides excellent exposure of acetabulum and femur
• Direct lateral approach: Good exposure with lower dislocation risk
• Anterolateral approach: Preserves posterior structures
• Direct anterior approach: Muscle-sparing, potentially faster recovery

Step-by-Step Surgical Procedure

1. Skin Incision and Superficial Dissection

   • Make skin incision (length varies by approach)
   • Divide subcutaneous tissue
   • Identify and protect neurovascular structures
   • Develop interval between muscles based on chosen approach

2. Deep Dissection and Joint Exposure

   • Identify and protect key neurovascular structures
   • Release appropriate tendons/muscles to expose hip joint
   • Dislocate the femoral head from acetabulum
   • Perform femoral neck osteotomy and remove femoral head

3. Acetabular Preparation

   • Remove labrum and any osteophytes
   • Expose native acetabulum
   • Sequential reaming of acetabulum to appropriate size
   • Test appropriate acetabular component size

4. Acetabular Component Implantation

   • Position acetabular component at proper inclination (approximately 40°) and anteversion (approximately 20°)
   • Impact the final acetabular component
   • Secure with screws if needed (for uncemented components)
   • Insert appropriate polyethylene liner

5. Femoral Preparation

   • Position leg for femoral canal access
   • Identify femoral canal entry point
   • Sequential broaching/reaming of femoral canal
   • Trial reduction with provisional components to assess stability, leg length, and offset

6. Femoral Component Implantation

   • Insert final femoral component (cemented or uncemented)
   • Allow cement to cure if using cemented technique
   • Place final femoral head component
   • Reduce the hip joint by placing femoral head into acetabular component

7. Final Assessment and Closure

   • Test range of motion and stability
   • Assess leg length and offset
   • Irrigate wound thoroughly
   • Place drain if needed
   • Repair capsule and soft tissues according to approach
   • Close fascia, subcutaneous tissue, and skin

Implant Selection Considerations

• Fixation Method:

  • Cemented components: Typically used in older patients with poor bone quality
  • Uncemented components: Rely on osseointegration, often used in younger patients

• Bearing Surface Options:

  • Polyethylene-on-metal articulation: Traditional, cost-effective 2
  • Ceramic-on-ceramic: Lower wear rates
  • Ceramic-on-polyethylene: Good wear characteristics
  • Highly cross-linked polyethylene: Improved wear resistance

Postoperative Management

• Pain Management: Multimodal approach including paracetamol, NSAIDs/COX-2 inhibitors, and opioids as needed 1
• Early Mobilization: Begin physical therapy on postoperative day 0-1
• Weight-Bearing Status: Depends on fixation method and surgeon preference
• Hip Precautions: Based on surgical approach to prevent dislocation
• Rehabilitation: Focus on hip abductor strengthening and functional recovery 1

Potential Complications

• Infection (most common cause for revision at 19.3%) 3
• Instability/dislocation (17.4% of revisions) 3
• Aseptic loosening (15.8% of revisions) 3
• Periprosthetic fracture
• Leg length discrepancy
• Venous thromboembolism
• Heterotopic ossification

Technical Pitfalls to Avoid

• Improper component positioning leading to impingement or dislocation
• Inadequate cement technique (if using cemented components)
• Femoral fracture during broaching or implant insertion
• Nerve injury (particularly sciatic nerve in posterior approach)
• Inadequate soft tissue tension leading to instability

Total hip replacement is a complex procedure requiring meticulous attention to detail at each step to ensure optimal outcomes. The specific technical aspects may vary based on surgeon preference, patient anatomy, and implant selection.