1. IL BONE-LOSS NELLA CHIRURGIA PROTESICA DI REVISIONE
PATOLOGIA DELL’ARTROSI COXOFEMORALE:
IL BONE-LOSS
NELLA CHIRURGIA PROTESICA DI REVISIONE
Stefano Zanasi
Policlinico di Monza
IV Unità Operativa di Ortopedia
Responsabile: Dr. Stefano Zanasi

2. STEFANO ZANASI

3. REVISION HIP ARTHROPLASTY
NEEDS
TO RECOGNIZE BONE LOSS

4. REVISION HIP ARTHROPLASTY OF BONE-LOSS CLASSIFICATION
NEEDS
OF BONE-LOSS CLASSIFICATION

5. BONE-LOSS CLASSIFICATION
PRE-OPERATIVE PLANNING
COMMON LANGUAGE for REPORTING SURGICAL RESULTS
( A.A.O.S. COMMITEE ON THE HIP, 1993 )

6. BONE LOSS CLASSIFICATIONS
Engelbrecht ( 1987 ) Oakeshott et Coll. (1987)
Gustilo-Pasternak (1988) Mallory et Coll. (1988)
Engh et Coll. ( 1988 ) Schmitt et Coll. (1992)
Tanzer et Coll. ( 1992 ) Pipino - Molfetta (1992)
Gross et Coll. ( Paprosky et Coll. (1993)
° Chandler et Coll. (1989) D’Antonio et Coll. (1995)

7. LIMITS of CLASSIFICATIONS
COMPLEXITY
RELATED to IMAGING
MANY CASES BORDERLINE
INTRAOPERATIVE DEVELOPMENT OF BONE
DEFECTS
difficulty in application

8. in hip revision surgery
The BONE-LOSS
CLASSIFICATION
in hip revision surgery
Italian Society of Revision Surgery-GIR

9. ACETABULAR BONE-LOSS GRADE I GRADE II GRADE III GRADE IV MASSIVE
° Loosening
° Enlargement and
deformation of
acetabulum
GRADE IV
° Loosening
° Enlargement and
deformation of
acetabulum
NO wall defect
° Loosening
° Enlargement and
deformation of
acetabulum
MASSIVE
and OVERALL
Periacetab.
Defect
Defect in TWO-
MORE walls
Defect in ONE wall

10. FEMORAL BONE-LOSS GRADE I GRADE II GRADE III GRADE IV Defect
Proximal canal
enlargement
with cortical
thinning
NO cortical zone defect
Proximal canal
enlargement
with cortical
thinning
Proximal canal
enlargement
with cortical
thinning
PROXIMAL
CIRCUMFE-
RENTIAL &
MASSIVE
Defect
Defect in TWO
or MORE
zones
Defect in ONE
cortical zone

11. (Grade I – cavitary defect)
ACETABULAR BONE-LOSS
(Grade I – cavitary defect)
Host bone CAN CONTAIN
the cup and ensure its
stability.
C.O.R. is not (or slightly)
translated
Loosening
Enlargement and
deformation of
acetabulum
NO WALL DEFECT

12. ACETABULAR BONE-LOSS FILLING of the cavity SURGICAL STRATEGY
(Grade I)
FILLING of the cavity
SURGICAL
STRATEGY
(Larger or elliptical cups, Cement, Bone chips, etc.)

15. ACETABULAR BONE-LOSS (Grade II )
Loosening
Enlargement and
deformation of
acetabulum
Defect in
ONE WALL
Host bone
MAY NOT CONTAIN
the Cup
C.O.R. always translated

16. (Rings, Cages, Conventional or Jambo cup, Bone grafts, etc.)
ACETABULAR BONE-LOSS
(Grade II)
RECONSTRUCTION
of the
DISRUPTED WALL
(Rings, Cages, Conventional or
Jambo cup, Bone grafts, etc.)
SURGICAL
STRATEGY

23. b a c

25. ACETABULAR BONE-LOSS (Grade III) - Host bone CAN'T CONTAIN the CUP
- DEFECT of
SUPPORTING WALL
- ARTICULAR BIOMECHANICS ALTERED
Loosening
Enlargement and
deformation of
acetabulum
Defect in TWO or
MORE WALLS

26. CUP ANCHORAGE in intact bone
ACETABULAR BONE-LOSS
(Grade III)
CUP ANCHORAGE
in intact bone
( Rings, Cages, Conventional
or Jumbo cup, Stemmed cup,
Oblong or asymetric cups,
Morsellized bone grafts, etc. )
SURGICAL
STRATEGY

31. ACETABULAR BONE-LOSS Host bone CAN’T CONTAIN the cup Biomechanics is
(Grade IV)
Host bone
CAN’T CONTAIN
the cup
MASSIVE
and
OVERALL
PERIACETABULAR
Defects
(hemipelvis fracture)
Biomechanics is
deeply altered

32. ANCHORAGE in the superior wall ACETABULAR BONE-LOSS (Grade IV)
SURGICAL
STRATEGY
(Rings, Cages, Stemmed
cups, Allografts, etc. )

39. (Grade I – cavitay defect)
FEMORAL BONE-LOSS
(Grade I – cavitay defect)
Proximal canal
enlargement
with cortical
thinning
NO CORTICAL
ZONE Defect
PROXIMAL FEMUR
CAN’T CONTAIN
the stem
Biomechanics is not altered
( leg length, muscle balance,
head/neck offset )

40. FILLING of the femoral canal SURGICAL STRATEGY
FEMORAL BONE-LOSS
(Grade I)
FILLING of the femoral canal
(larger and longer stem, cement,
morsellized grafts, etc.
Restoring the appropriate
head-neck offset
SURGICAL
STRATEGY

49. (Grade II – segmental defect)
FEMORAL BONE-LOSS
(Grade II – segmental defect)
Proximal femur MAY
CONTAIN the stem
and ensure its stability.
Biomechanics is
partially compromised
Defect in ONE
CORTICAL
ZONE
(Lesser trochanter,
reabsorption,
osteolysis, perforation,
window, etc.)

50. FEMORAL BONE-LOSS SURGICAL STRATEGY
(Grade II)
RECONSTRUCTION
of cortical defect
(bone grafts, proximal anchorage
with long stem, ev. cerclages )
Restoring the appropriate
head/neck offset
SURGICAL
STRATEGY

60. Proximal femur FEMORAL BONE-LOSS (Grade III) CAN'T CONTAIN and
STABILIZE the stem
Biomechanical ability
is significantly compromised
Defect of TWO or
MORE ZONES
total PROXIMAL
CIRCUNFERENTIAL
defect

61. FEMORAL BONE-LOSS SURGICAL STRATEGY
(Grade III)
ANCHORAGE in INTACT BONE
(Below the defect)
Modular or Custom-made stems
Distal anchorage stems
Massive allografts,
SURGICAL
STRATEGY

68. FEMORAL BONE-LOSS (Grade IV)
Proximal bone
CAN’ T CONTAIN
the stem
Biomechanical ability
is significantly compromized
PROXIMAL
CIRCUNFERENTIAL
MASSIVE
defect

69. FEMORAL BONE-LOSS (Grade IV) SURGICAL STRATEGY
ANCHORAGE the stem
in distal bone
SURGICAL
STRATEGY
Massive allografts,
Distal anchorage stems,
Modular stems (tumor prosth.)

74. Grazie