Background: The role of polyethylene (PE) wear in relation to synovitis and elevated hydrostatic pressure in the loosening process after THA has gained increased attention. The aim of our study was to investigate the correlation between prosthetic head size, PE wear and sonographic capsular distention, reflecting the degree of intracapsular synovitis/synovia/hydrostatic pressure.

Patients and methods: In 2005 we analyzed 60 randomly selected and unrevised OA patients 10 years after surgery with 32 or 28mm femoral heads. We evaluated radiographic signs of loosening, linear and volumetric PE wear. Sonographic examination was performed to measure the “capsular distance”, i.e. the capsular distension, defined as the distance between the metallic echo from the anterior surface of the prosthetic femoral neck, and the echo from the anterior surface of the anterior capsule.

Results: The linear wear was 0.2 mm per year and 0.1 mm per year in the 32 mm and 28 mm head size group respectively (p< 0.001), the volumetric wear was 139 mm3/year and 48 mm3/year (p< 0.001), and the capsular distention was 17 mm and 13 mm respectively (p< 0.001). There was also a significant positive correlation between PE volumetric wear and capsular distension (r=0.63, p< 0.001).

Interpretation: We conclude that 32 mm femoral heads were associated with almost three times higher volumetric wear as compared to 28 mm heads, and increased “capsular distension”, reflecting increased synovitis/synovia/hydrostatic pressure in prosthetic hip.

Aims: To compare mosaicplasty with microfractures in the knee joint osteochondral defects treatment. Methods: Between 1998 and 2001 twenty-three patients underwent mosaicplasty and 23 patients (controls) microfracture procedures for the knee joint osteochondral or chondral pathology treatment. Patients were selected and evaluated randomly through ICRS and modiþed HSS scales, arthroscopicaly, histologically, rent-genologicaly and with MRI. Average follow-up was 12,4(range 10–14 months) and 23,6 months (range 22 –25 months). Results: The defect-size in these patients ranged between 12 mm² and 23 mm² in diameter and had an average-size of 15 mm². 22(95,6%)mosaicplasty results were excellent and good at the time of last follow-up. 16(69,5%) in the control group results were excellent and good and 7(30,4%) Ð fair 23,6 months post operations. Modiþed ICRS and HSS evaluations showed statistically signiþcantly better results in the mosaic-plasty group at the 12,4 and 23,6 months (p< 0.005; p< 0.0001) post operations. Last follow-up showed deterioration in microfracture group (p< 0,02). Conclusions: Mosaicplasty can be recommended for the treatment of osteochondral defects in the weight-bearing area of the knee as a safe procedure for transplantation of hyaline cartilage.

Aims: Retrospective study comparing long term results after excision of osteochondral defects of the knee joint in different age groups. Methods: Fiftytwo patients with osteochondritis dissecans lesions were evaluated between 7 and 25 years after excision of a partially detached or loose fragment from the medial femoral condyles. Average follow-up was 17,2(range 7–25 years). Two groups with the same defect size and activity level during procedures were made, with 31 patients in þrst and 21 Ð in the second group. The only difference between the groups was the age; the age average in the þrst group was Ð 25,6 years (range 15 to 35 years), and Ð 45,2 years (range 35 to 55 years) in the second group. Patients were evaluated through ICRS, modiþed HSS and KOOS scales, and with x-rays. Results: Evaluation with the ICRS, modiþed HSS and KOOS rating scales for osteochondritis dissecans revealed Ð 9(17%) good results, 32(62%) Ð fair, and 11(21%) Ð failure results. Final ICRS and modiþed HSS evaluation showed statistically signiþcantly better results in the younger patients group at the 21 years (p< 0.04). At an average 17,2 year follow-up x-rays and KOOS evaluation form showed initial and second-degree (according to AhlbŠck) osteoarthritis signs in the knees. Conclusions: The long-term results of the excision of osteochondral defects of the knee joint are poor. We recommend autologous osteochondral grafting for the replacement of the osteochondritis dissecans defects in the knee joint.