This 1994 landmark paper by Paprosky et al. introduces a three-type classification for acetabular bone defects encountered at revision hip arthroplasty. It reports 6-year outcomes for 147 consecutive cemented acetabular revisions reconstructed with cementless hemispherical press-fit components, with or without allograft. The central question: can defects be systematically classified, and do reconstruction strategies matched to defect type produce reliable results?
Every revision hip case starts the same way: look at the AP pelvis and ask how much acetabular bone is left. The Paprosky classification gives you a systematic answer tied directly to a reconstruction plan.
When you see cup migration >2 cm with teardrop obliteration and ischial lysis, that is a Type 3B defect. It needs a proximal femoral arc allograft fixed with a pelvic reconstruction plate, and you should counsel the patient that even with successful graft incorporation, failure is possible if residual host-bone contact falls below 50%.
For Types 1 and 2, the rim and columns are still working for you. Particulate graft or a bulk femoral head allograft is usually sufficient, and you can expect >96% implant survival at 6 years.
The paper also taught us that early migration under 3 mm in the first year is normal and represents graft revascularization, not failure. Migration that stops by 12 months and does not progress is reassuring. Migration that continues past 1 year is not.
This classification remains the standard language for acetabular bone loss in revision hip surgery and is the scaffolding on which all subsequent work — trabecular metal augments, cup-cage constructs, pelvic discontinuity management. Is built.
This 1994 landmark paper by Paprosky et al. introduces a three-type classification for acetabular bone defects encountered at revision hip arthroplasty. It reports 6-year outcomes for 147 consecutive cemented acetabular revisions reconstructed with cementless hemispherical press-fit components, with or without allograft. The central question: can defects be systematically classified, and do reconstruction strategies matched to defect type produce reliable results?
Every revision hip case starts the same way: look at the AP pelvis and ask how much acetabular bone is left. The Paprosky classification gives you a systematic answer tied directly to a reconstruction plan.
When you see cup migration >2 cm with teardrop obliteration and ischial lysis, that is a Type 3B defect. It needs a proximal femoral arc allograft fixed with a pelvic reconstruction plate, and you should counsel the patient that even with successful graft incorporation, failure is possible if residual host-bone contact falls below 50%.
For Types 1 and 2, the rim and columns are still working for you. Particulate graft or a bulk femoral head allograft is usually sufficient, and you can expect >96% implant survival at 6 years.
The paper also taught us that early migration under 3 mm in the first year is normal and represents graft revascularization, not failure. Migration that stops by 12 months and does not progress is reassuring. Migration that continues past 1 year is not.
This classification remains the standard language for acetabular bone loss in revision hip surgery and is the scaffolding on which all subsequent work — trabecular metal augments, cup-cage constructs, pelvic discontinuity management. Is built.