Intraoperative acetabular fracture and pelvic discontinuity in thr

1. Intraoperative acetabular fracture
and pelvic discontinuity in THR –
Leave it or Treat it

2. • Periprosthetic acetabular fracture rare
complication.
• Increasing incidence with uncemented cups

3. Periprosthetic Acetabular fracture
• Intraop. fracture with comp. Insertion
• Intraop. fracture with comp. Removal
• Traumatic Fracture
• Spontaneous Fracture
• Pelvic discontinuity

4. Intraop Periprosth. Acetabular fracture
with Component insertion
• Exact prevalance unknown
• Depends on –
a) Surgical tech. used for comp. stability
b) Quality of host bone

5. Surgical technique used for
component stability
• Line to line reaming -
- size of comp. same as last reamer diameter
- adjunctive screw used for fixation
Disdavantage of screw fixation
Neurovascular inj
fretting & corrosion
wear & osteolysis

6. Surgical technique used for
component stability
• Under Reaming of Acetabulum
Reamer 1-2 size smaller than component
Stability without adjunctive screws
Incidence of intraop. fracture

7. Intraop Periprosth. Acetabular fracture
Cadaver studies
• Kim et al
• Increased incidence with comp oversized by
2-4 mm
• Smaller sized acetabulum – higher chance of
intraop fracture
• Large size acetabulum – rim fracture
• Small size acetabulum - coloumn fracture

8. Intraop Periprosth. Acetabular fracture
Experimental studies
• Ries et al
Small sized acetabulum underream by 1
Large sized acetabulum undreream by 3

9. • Series of 13 periprosthetic acetabular fracture
• 11 occurred in women above 60 with Rh. Arth.
• Quality of host bone important factor
• 4 fracture diagnosed pot op – 2 reqd revision
and I case component migrated substantially

10. Tips to avoid
Intraop Periprosth. Acetabular fracture
• Careful reaming avoiding violation of ant.,
post. Or medial wall.
• Failure of component to advance with
progressive blows – additional reaming.
• Avoid underreaming > 2mm
• Osteopenic bone – minimal underreaming
/line to line contact
• Avoid overreaming around dome of prosthesis
– leads to fracture

11. Pelvic Discontinuity
• Separation of sup. portion of acetabulum from
inf. portion
• Usually seen in cases of revision THR

12. Pelvic Discontinuity
• Radiological indicator
- Transverse fracture line
- Medial translation of inf. portion of
hemipelvis
- break in ilioischial line
- Rotation of inf hemipelvis
- asymmetric obturator rings

13. Classification system

14. Intraop Periprosth. Acetabular fracture
• Recognize fracture occurred
• Assess – displaced / undisplaced
• Stability of implant
• X_ ray – Obturator and Iliac views

15. Intraop. Management
• Type IA
• Fracture involves the wall in Type IA
• Fracture undisplaced and component stable
- Leave the component in place
- Use adjunctive screws

16. Intraop. Management
• Type IB
- Fracture involving Column
- Implant Unstable
• Remove component & Reduce fracture – internal
fixation with plate and screws
• Line to line reaming
• Implant Multihole acetabular cup
• Post op IA & IB – Toe touch weight bearing 6 – 12
weeks

17. Intraop. Management
• Type IC
• Fracture not recognised intraoperatively
• Component migration postoperatively
• Failure

18. Intraop. Management
• Type IC
• Trial of extended toe touch weight bearing
• Early acetabular revision after discussion with pt.
• Failure rate
Component fixed without screws
Involvement of column
Fracture displaced

19. Intraop. Management
• Pelvic Discontinuity
• < 50% bone loss
- Hemispherical porous coated acetabular cup
- Posterior plate and screws
- Morcellized bone graft at site of discontinuity
• > 50% bone loss – Acetabular reconstruction cage

20. Periprosth. Acetabular fracture
Treatment Algorithm

21. Periprosth. Acetabular fracture
Treatment Algorithm

22. Summarize
• Intraop periprosthetic acetbular frature complex
injuries
• Implant should be stable
• Rigid fixation of fracture & bone grafting
• Assess remaining host bone
• Loss > 50% bone – Acetabular cage from ilium to
ischium