This document discusses bone quality assessment and femoral defects in revision total hip arthroplasty (THA). It outlines common causes of THA failure, including wear, loosening, osteolysis, and infection. Modalities for assessing bone stock are described, such as X-ray, CT, DXA, MRI, and bone scans. The Paprosky classification system for femoral bone deficiencies is explained. Considerations for revision THA include supporting the metaphysis and isthmus, stem type selection, and achieving stable fixation while avoiding fractures.

1. BONE QUALITY AND FEMUR DEFECT
ASSESSMENT IN REVISION THA
Dr KANTHI KIRAN G
RAKSHA HEALTH CARE

2. CAUSES OF FAILURE
• Wear of articular bearing surface
• Aseptic/mechanical loosening
• Osteolysis
• Infection
• Instability
• Peri-prosthetic fracture
• Implant Failure
• Subsidence

3. Complications after THR
• Early (<10%)
• Dislocation
• Infection
• Late (> 3-5 yrs post op)
• Wear of articular bearing surface
• Osteolysis
• Mechanical loosening
• Peri-prosthetic fracture
• Implant failure

4. FEMUR ANATOMY
• Bowing
• Anteversion
• Retroversion
• Coxa valga
• Coxa vara

5. ASSESSMENT MODALITIES
• X RAY
• CT
• DXA
• MRI
• BONE SCANS

6. X RAY
• 4 VIEWS
• PELVIS AP
• AP OF THE AFFECTED HIP
• LATERAL VIEW
• SHOOT THROUGH LATERAL

8. CT, SPECT and MRI
• CT scans have also been useful in planning for revision surgery and is an
excellent tool for evaluating component positioning
• MRI is useful in the evaluation of failed metal on metal total hip
arthroplasty, where with special metal artifact subtraction sequences it can
be used to demonstrate adverse local tissue reactions
• Other uses of MRI are to evaluate the soft tissue status in osteolysis with
cortical breaches
• SPECT in addition to CT will give better understanding of loosening and
heterotrophic ossification

9. Bone scans
• Suspicion Of Infection Is An Indication For Bone
Scans
• The Combination Of Technetium- Or Indium
Labeled White Cells And Technetium-labeled
Sulfur Colloid Has Excellent Results, With
Accuracy Of Over 90% In Assessing The Focus
• Fluorodeoxyglucose–positron Emission
Tomography (FDG-PET) Scanning Has Variable
Performance
• Aseptic Loosening Related To Particle Disease
Can Cause Increased FDG Uptake
FDG-
PET

11. REVISION THA CONSIDERATIONS

12. REVISION THA CONSIDERATIONS

13. CLASSIFICATION: Paprosky Classification of Femoral Bone Deficiencies
• Type I: Minimal loss of metaphyseal cancellous bone with intact diaphysis
• Type II: Extensive loss of metaphyseal cancellous bone with intact diaphysis
• Type IIIA: Severely damaged, nonsupportive metaphysis, with >4 cm of intact diaphyseal bone
available for distal fixation
• Type IIIB: Severely damaged, nonsupportive metaphysis, with <4 cm of intact diaphyseal bone
available for distal fixation
• Type IV: Extensive damage to metaphysis and diaphysis, with widened femoral canal,
nonsupportive isthmus

14. Type I
Minimal loss of
metaphyseal
cancellous bone with
intact diaphysis

15. Type II
Extensive loss of
metaphyseal cancellous
bone with intact
diaphysis

16. Type IIIA
Severely damaged,
nonsupportive metaphysis,
with >4 cm of intact
diaphyseal bone available
for distal fixation

17. Type III B
Severely damaged,
nonsupportive metaphysis, with
<4 cm of intact diaphyseal bone
available for distal fixation

18. Type IV
Extensive damage to
metaphysis and diaphysis,
with widened femoral canal,
non-supportive isthmus

19. Other classifications –
American Academy of Orthopaedic Surgeons Femoral Bone Loss
Classification Type Description
• I Segmental defect
• II Cavitary defect
• III Combined segmental and
• cavitary defect
• IV Femoral malalignment
• (rotational or angular)
• V Femoral stenosis
• VI Femoral discontinuity

20. HOW? METAPHYSIS SUPPORT
ISTHMUS SUPPORT
PRIMARY STEM
TAPERED STEM
13 CM BONE FROM
INTERCONDYLAR NOTCH
CEMENTED
PROSTHESIS LONG
STEM/ DISTAL LOADING
STEM UNCEMENTED
AT LEAST 2.5 MM
THICKNESS OF CORTICAL
BONE OVER A DISTANCE OF
AT LEAST 6 CM? IN DISTAL
DIAPHYSIS
MEGAPROSTHESIS/
OSSEOINTEGRATION
DEVICES
TOTAL FEMUR
NO
YES
YES
NO
NO
NO

23. LITERATURE
• John Callaghan, THE ADULT HIP, HIP ARTHROPLASTY SURGERY, 3rd edition, wolters kluwer
• Neil P. Sheth, MD, et al, Femoral Bone Loss in Revision Total Hip Arthroplasty: Evaluation and Management; J
Am Acad Orthop Surg 2013;21: 601-612
• Cavalli L and Brandi ML. Periprosthetic bone loss: diagnostic and therapeutic approaches F1000Research 2014,
2:266
• Lombard, C et al; Imaging in Hip Arthroplasty Management Part 2: Postoperative Diagnostic Imaging strategy. J.
Clin. Med. 2022, 11, 4416. https://doi.org/ 10.3390/jcm11154416
• Dobrindt et al. Hybrid SPECT/CT for the assessment of a painful hip after uncemented total hip arthroplasty;
BMC Medical Imaging (2015) 15:18
• James V Bono; REVISION HIP ARTHROPLASTY, 1999 Springer-Verlag

24. • Stable fixation is to be achieved on table with available bone
• Care should be taken to avoid intraoperative fractures
• Extensive pre operative planning

25. THANK YOU