Journal Club

March 2010

Two stage revision arthroplasty of the hip for infection using an interim articulated Prostalc hip spacer. A 10-15 year follow up study.

Biring et al

University of British Columbia, Vancouver, Canada

JBJS Br November 2009

No external funding or benefit recieved

Reviewed by

Dr Owen Mattern
MBBS | Unaccredited Orthopaedic Registrar

Introduction

  • Deep infections after THR difficult to treat
  • Number of options
    • 1 stage
    • 2 stage
      • Articulated spacer - was used in this study
      • Non-articulated spacer
      • Time to second revision

Aims

  • Primary
    • Determine whether two-stage revision with Prostalac articulated hip spacer and other management principles were associated with eradication of infection
  • Secondary
    • Assess quality of life and satisfaction of patients
    • Survivorship of the revised THR

Methodology

  • Retrospective cohort study
    • Level 4 evidence
    • Approved by institutional review board
  • Patients identified off database who had been treated with Prostalac spacer
    • Nov 1989 - June 1996
    • 103 patients
    • 92 were followed up (44 deceased, 48 alive)
    • Patients/NOK/medical records/GP’s contacted
  • Information collected
    • Recurrence of infection
    • Undergone or awaiting further revision surgery
    • Tests for suspected infection
  • Quality of life measures were obtained
    • WOMAC OA index
    • Oxford-12
    • SF-12
    • UCLA activity scale
    • Satisfaction questionnaire
    • Charnley class of coomorbidity

Operative Technique

  • Prostalac system (Depuy, Warsaw Id)
    • Acetabular component
      • Triflanged poly cup contrained to femoral head
      • Antibiotic laden cement
    • Femoral component
      • Standard and long stem within a sleeve of antibiotic laden cement
      • Pressfit to achieve vertical and torsional stability
  • Combination of Abx used in cement
  • No drains

Post OT

  • PWB
  • IVABx for 6/52
  • Hip aspiration at 10/52
  • Second stage revision mean 5 months (1-36)
  • Prostalac removed “usually with ease”
  • IVAbx until final intraoperative cultures available

Approach

  • Lateral - 51 patients
  • Trochanteric osteotomy - 30 patients
  • Posterior - 17 patients
  • MacFarland-Osborne approach - 1 pt
    • 19 required extended trochanteric osteotomies

Prosthesis

  • Femoral
    • 14 proximal femoral replacements
    • 4 allograft prosthesis composites
    • 62 cemented
    • 19 uncemented
  • Acetabulum
    • 91 uncemented
    • 5 bipolar
    • 3 cemented

Statistics

  • No discussion regarding statistical analysis used

Results

  • 103 patients
    • 4 had only 1 stage performed - excluded
  • Indication
    • 92 prosthetic infection
    • 5 sepsis native hip
    • 2 infected ORIF proximal femur
  • 92 were followed up
    • 7 lost to follow-up
      • 2 infections (included in results)
    • 92 patients
      • 44 died, 48 were alive
    • Mean f/u 12 years (10-15years)
Organism Number
Staph Epi (9 MRSE) 22
Staph Aur (1 MRSA) 22
Multiple Organims (Staph/strep) 20
Strep Species 12
Other Gram negative 10
Other Staph species 4
E-Coli 3
Mycobacterium tuberculosis 1
No Organism 5

 

Abx in cement

  • Vancomycin/tobramycin - 86 patients
  • Tobramycin/Pen G - 6 patients
  • Tobramycin - 3 patients
  • Vancomycin/Pen G - 2 patients
  • Streptomycin - 1 pt
  • Ceftizoxime - 1 pt

11 reinfections (included 2 lost to follow-up)

  • 89% eradication rate
  • 7 responded to subsequent surgery
  • 2 resection arthroplasties
  • 1 hip disarticulation
  • 1 sinus and suppressive Abx

Further operation in 9 - not related to infection

  • 4 aseptic loosening - 3 both, 1 acetabulum
  • 2 dislocators
  • 1 dislocator and periprosthetic #
  • 1 periprosthetic fracture
  • 1 removal of cable and claw

Quality of Life Outcomes

  • 38/48 patients completed data
  • Not well documented
  • Similar Charnley class
  • Only comment that outcomes are similar to other revision patients
    • Good WOMAC score
    • Below average physical scores - Oxford, SF12
    • Average mental score
    • High satisfaction score - 90.5%
    • Mild activity level - limited housework, shopping and walking

Discussion

  • Successful long-term eradication
  • Out to 10 years
  • Comparable to other 2 stage revision publications

Pros of Study

  • Long-term follow-up of large group of patients
  • Well operative and post-operative regime
  • Included details regarding re-operation for all causes

Cons of Study

  • Poor detail regarding quality of life measures and results
  • Oxford 12 score is out of either 48 or 60
  • They gave score as being 74
  • Do not explain satisfaction score
  • High mortality rate

Take home message

Two stage revision using a Prostalac spacer and antibiotic cement can achieve high eradication rate over the long-term

 

Webpage Last Modified: 24 May, 2010
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