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 e-mail: zanasis.orth@virgilio.it

STEFANO ZANASI

REVISION HIP ARTHROPLASTY NEEDS TO RECOGNIZE BONE LOSS

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

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

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. (1993 - Paprosky et Coll. (1993) ° Chandler et Coll. (1989) - D’Antonio et Coll. (1995)

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

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

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

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

(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

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.)

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

(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

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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

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

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

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

(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 )

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

(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.)

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

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

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

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

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

Grazie