[Revision of total hip replacement operations at the Orthopedic Clinic IPVZ in Prague, 1999].

Purpose Of The Study: The aim of the work is to evaluate the results of revision surgeries of total hip replacements at the Orthopaedic Department IPVZ in 1999.

Material: Revision surgery of 61 THR was performed at the Orthopaedic Department IPVZ in 1999. Most of them (54) were reoperated for aseptic loosening of the cup or both components, 4 patients for aseptic loosening of the stem, 1 patient was reoperated for recurring dislocation of THR and 2 patients for septic loosening. Eleven loosened 44/32 Poldi cups were reoperated on average after 160 months, twelv 49/32 Poldi cups on average after 143 months and seven 54/32 Poldi cups on average after 111 months. Sixteen loosened Walter Motorlet cups were reoperated on average after 111 months, 16 loosened Walter-Motorlet cups were revised on average after 83 months, 3 Martin cups on average after 112 months. Another 4 cementless cups of different provenance were reoperated in the interval of 9-54 months after the primary operation.

Methods: For the revision surgery we used 28 times Zweymüller Bicon cementless cup and in 26 hip joints Poldi cemented cup, in 6 patients we applied structural bone allografts, in 31 patients morselized allografts prepared on a bone mill. For the revision surgery of loosened stems we used in 18 patients Zweymüller SL Plus stem and in 7 patients Zweymüller SLR stem.

Discussion: From the viewpoint of long-term results THR implanted in patients with a secondary postdysplastic osteoarthritis is more risky than in the patients with a primary degenerative affection of the joint. It has been proved that also a cemented total hip replacement may bring good long-term results comparable with the results of some cementless implants.

Conclusion: In most of the patients the primary diagnosis was postdysplastic osteoarthritis of the hip joint. Recently the need has started to grow for revision surgery in patients with loosened modern cementless implants. In revision surgeries the system of cementless THR of Zweymüller type proved suitable. The need for the application of bone allografts was quite frequent.