Purpose: To assess the safety and efficacy of using mini-incisions (? 10 cm) in the implantation of total hip prostheses.

Materials and methods: A prospective study was carried out to compare a cohort of 25 total hip prostheses implanted using a posterior approach through mini-incisions (mean length 9.4 cm, range: 8–10) with another 25-patient cohort where the incisions were of standard length. Patients in both groups had a similar gender distribution, similar ages (± 3 years), weight (± 3 kg) and height (± 3 cm). The type of implant used was also similar. Statistical analysis used: Chi-square, Mann-Whitney U test and Student’s t test.

Results: After 6 months, no significant differences were observed in the body mass index, femoral cortical index, intraoperative or postoperative complications, cup diameter, stem size, cup inclination, stem alignment, quality of femoral cementation, metaphyseal and isthmic filling of the stem, leg length discrepancy, number of blood units transfused, hemoglobin and hematocrite levels 6 hours post-op, in the decline of these levels from those of the preop period or in the Harris Hip Score values. The mini-incision group showed higher haemoglobin and hematocrite levels after 48 hours and a lower reduction of these values from preop to 48 hours after surgery and a lower suction drain. Fewer patients of these patients needed a transfusion, they were the first to sit and start walking and they had significantly shorter hospital stays. Mean follow-up was 20 months.

Conclusions: Total hip prostheses can be implanted through mini-incisions in a safe and reproducible way and lead to a better, faster recovery without additional complications, with the same degree of precision and similar clinical results.

Aims: Clinical and radiographic evaluation of retinacular lateral releases using an arthroscopic approach, for anterior knee pain in cases with slight patelar axial malposition Methods: Prospective study in 34 patients. Evaluation according to the Insall clinical score, patient opinion, and change in radiographic angles and index from pre-operative to post-operative. Results: Postoperative clinical score (Insall 1983): 82% excellent; 6% good; 6% poor; 6% bad. Angular values: patelar index (Cross 1976) of 7,1 and sulcus angle (Brattstrom 1964) of 139,6∞. Radiographic correction: from 15,7 to 17,9 in patello-femoral angle (Laurin 1978); from −5,6 to −5,3∞ in congruency angle (Merchant 1974); and from 1,37 to 1,12 in patello-femoral index (Laurin 1978). Conclusions: Clinical results, patient satisfaction, and radiographic correction of congruency angle, patello-femoral angle and patello-femoral index make justifiable the use of arthroscopic lateral releases in the treatment of selected cases of patello-femoral pain.