What are the common postoperative complications after total hip arthroplasty (THA) and how should each be managed?

Common Hip Injuries After Total Hip Arthroplasty and Their Management

The most common complications after total hip arthroplasty are periprosthetic joint infection (19.3%), dislocation (17.4%), and aseptic loosening (15.8%), with each requiring distinct management strategies prioritizing implant salvage when possible and revision surgery when necessary. 1

Major Complications and Their Management

Periprosthetic Joint Infection (PJI)

For suspected infection, immediately obtain deep tissue specimens (minimum three intraoperative samples) rather than superficial swabs, which are misleading and promote unnecessarily broad antimicrobial treatment. 2

Diagnostic Warning Signs

• Pain persisting beyond 6 months after surgery 2
• Draining sinus tract from the surgical site 2
• Wound discharge lasting 5 or more days postoperatively 2

Surgical Management Algorithm

• Early infections (<30 days) or acute hematogenous infections with short symptom duration: Debridement with implant retention 2
• Late infections (>30 days), prosthesis loosening, sinus tract present, significant tissue damage, or failed debridement: Two-stage exchange arthroplasty 2
• Select cases with known organism, favorable susceptibility, adequate bone stock, good soft tissue, and no immunocompromise: Consider one-stage exchange 2

Antimicrobial Therapy

• Standard duration: 4-6 weeks IV pathogen-specific therapy, followed by oral antimicrobials for total 3 months 2
• For Staphylococcus aureus: IV cefazolin or vancomycin; oral cephalexin 2
• For streptococcal infections: IV penicillin G, ceftriaxone, or vancomycin; oral penicillin V, amoxicillin, or cephalexin 2
• If surgery refused or exhausted: Chronic oral suppression with organism-specific antibiotics 2

Risk Factors

• Diabetes and immunocompromise significantly increase infection risk 2
• Inflammatory arthritis (RA, SpA, SLE) patients have 50% increased PJI risk compared to osteoarthritis patients 1
• Immunosuppressant therapy and wound complications 2

Dislocation

Dislocation occurs in 0.35-17.4% of cases and requires immediate closed reduction followed by investigation of underlying causes. 1, 3, 4

Risk Factors

• Neuromuscular and cognitive disorders 3
• Patient non-compliance 3
• Previous hip surgery 3
• Surgical approach (though contemporary posterior approach with soft-tissue repair shows rates as low as 0.35%) 4
• Component malposition 3
• Inadequate soft-tissue tension 3
• Small femoral head size 3

Management Strategy

• First dislocation: Closed reduction, typically successful; nonsurgical management with activity modification and bracing frequently prevents recurrence 3
• Recurrent dislocation with identifiable cause: Target underlying etiology with soft-tissue tensioning (capsulorrhaphy or trochanteric advancement), correction of malpositioned components, or improving head-to-neck ratio 3
• Persistent instability without clear cause: Constrained cup or bipolar femoral prosthesis as salvage 3

Aseptic Loosening

Aseptic loosening remains the leading cause of revision THA (66.6% of revisions), typically occurring in the late postoperative period. 5

Clinical Presentation

• Progressive pain with weight-bearing 5
• Occurs more commonly >2 years after primary surgery 5
• Mean time to revision for loosening: 8.8-10.2 years 5

Management

• Revision arthroplasty with uncemented components shows excellent 10-year survivorship (98%) in contemporary series 6
• Address bone loss with appropriate grafting or augments 6

Periprosthetic Fracture

Periprosthetic fractures occur in 5.5% of revision cases and are the most common cause for readmission (0.52%) in the early postoperative period. 1, 4, 5

Management Approach

• Stable implant: Open reduction internal fixation around the prosthesis 4
• Loose implant: Revision arthroplasty with fracture fixation 4
• Vancouver classification guides treatment decisions 4

Osteolysis and Wear

Osteolysis accounts for 6-7.5% of revisions and is increasing in incidence with longer implant survival. 1, 5

Management

• Revision with removal of wear debris and granulation tissue 5
• Exchange of polyethylene liner if acetabular shell stable 5
• Complete component revision if extensive bone loss 5

Heterotopic Ossification (HO)

HO occurs in 46.7% of patients after revision surgery for PJI, with high-grade HO (Brooker 3-4) significantly limiting function. 7

Risk Factors

• Male gender (OR 2.14) 7
• Smoking (OR 5.75) 7
• Chronic infection (OR 3.54 for high-grade HO) 7
• Multiple surgical procedures 7

Prevention and Management

• Prophylaxis with NSAIDs or radiation therapy in high-risk patients 7
• Surgical excision for symptomatic high-grade HO after maturation 7

Special Considerations for Patients with Rheumatic Diseases

Perioperative Medication Management

For patients on immunosuppressive therapy, withhold biologic medications for one dosing cycle prior to surgery and restart after wound healing (typically 14 days), while continuing nonbiologic DMARDs throughout the perioperative period. 1

• Nonbiologic DMARDs: Continue throughout perioperative period 1
• Biologic agents: Withhold as close to 1 dosing cycle as scheduling permits; restart after evidence of wound healing 1
• Glucocorticoids: Optimize perioperative dosing per guideline recommendations 1

Critical Pitfalls to Avoid

• Never assume postoperative joint pain and effusion represent normal inflammation without ruling out infection, especially with warning signs 2
• Never rely on superficial wound swabs for microbiologic diagnosis 2
• Never ignore pain persisting beyond 6 months as this indicates potential complication requiring investigation 2
• Never delay intervention for suspected infection as early treatment improves outcomes and implant salvage rates 2

Imaging Recommendations

For suspected complications, radiographs remain first-line, with metal artifact reduction MRI (MARS-MRI) or CT (MAR-CT) for soft tissue evaluation around prostheses. 1

• Standard radiographs: Initial evaluation for loosening, fracture, dislocation 1
• MARS-MRI: Soft tissue assessment including pseudocapsule, tendons, pseudotumors 1
• MAR-CT: Evaluation of bone stock and component position 1
• Ultrasound: Soft tissue assessment without metallic artifact, though limited for deep structures 1