[The uncemented cup of the CLS Spotorno joint endoprosthesis--5-years' results].

PURPOSE OF THE STUDY

Authors report on five-year results in patients after THR operated on between 1994 and 1995 in which a cementless CLS Spotorno cup was used.

MATERIAL

In the given period 59 patients were operated on (35 women and 24 men). The average age at the time of implantation was 54.6 years. The most frequent causes of the indication for THR was primary osteoarthritis of the hip in 27 patients and postdysplastic osteoarthritis in 16 patients. Applied were 46-62 mm cups for 28 mm and 32 mm diameters of the head. The femoral component used was a cementless Poldi--42 times, cemented MS-30--16 times and cementles CLS--once. The surgical approach was first anterolateral, later Bauer transgluteal approach which allows a better visualization of the location during the reaming of acetabulum and cup positioning. The reaming of acetabulum and implantation of the cup were performed in a standard way. Prior to incision Kefzol (cefazolin) was administered intravenously in the dosage of 2 g. In patients with a preceding operation on the hip joint the administration of Kefzol was extended to 24 to 72 hours (3 x 1 g each 8 hours intravenously). Standard antithrombotic prevention by miniheparinization was applied in all patients until they were able to walk with the help of crutches (7 to 10 days). In case of an increased risk of thromboembolic complications heparin with a low molecule weight (Fraxiparine) was applied over the same period.

METHODS

In the period between autumn 1999 and spring 2000 clinical examination of the patients operated on was performed together with a radiograph of the hip joint involved. Clinical findings were evaluated after Harris hip score. Radiograph findings were compared to the postoperative and the control ones made one year after the operation. Evaluated were the position of components and signs of their loosening, if any.

RESULTS

After the average follow-up of 59 months 57 patients were checked. Excellent results according to Harris were achieved in 40 patients, good results in 13 patients and satisfactory results in 4 patients. No poor result was recorded. Radiographs proved a full integration of CLS Spotorno cups without any signs of loosening in all checked patients.

DISCUSSION

Not very numerous works in both foreign and domestic literature list according to the experience of individual authors the following advantages of CLS Spotorno cup: a small bone loss during reaming of acetabulum, excellent primary stability, excellent secondary stability and its easy reimplantation as compared to all types of cementless cups. Only in one female patient after a peroperative fissure of proximal femur the control examination showed a lower value of Harris score than was the average value of the whole group. Similarly, the Harris score was lower in female patients who postoperatively experienced complications of neurological and internal nature (1 temporary paresis of n. ischiadicus, 1 phlebothrombosis of veins of the limb operated on). Control radiograph examination proved a full bone integration without signs of loosening in both components of the implant in all 57 checked patients.

CONCLUSION

After five years the authors have a good experience with CLS Spotorno cup and recently they have started to indicate it more often in postdysplastic coxarthrosis in younger patients and in revision surgery for aseptic loosening of a cup. In young patients they recommend its matching with CLS Spotorno cementless femoral component and in middle-aged patients its matching with MS-30 (Morscher-Spotorno) cemented femoral component the centralizer of which allows an ideal anchoring of the stem in the cement mantle.