Sang Jun Song

Closed-wedge high tibial osteotomy using computer-assisted surgery compared to the conventional technique

We assessed the reliability, accuracy and variability of closed-wedge high tibial osteotomy (HTO) using computer-assisted surgery compared to the conventional technique. A total of 50 closed-wedge HTO procedures were performed using the navigation system, and compared with 50 HTOs that had been performed with the conventional technique. In the navigation group, the mean mechanical axis prior to osteotomy was varus 8.2 degrees, and the mean mechanical axis following fixation was valgus 3.6 degrees. On the radiographs the mean pre-operative mechanical axis was varus 7.3 degrees, and the mean post-operative mechanical axis was valgus 2.1 degrees . There was a positive correlation between the measured data taken under navigation and by radiographs (r > 0.3, p < 0.05). The mean correction angle was significantly more accurate in the navigation group (p < 0.002). The variability of the correction was significantly lower in the navigation group (2.3 degrees vs 3.7 degrees , p = 0,012). We conclude that navigation provides reliable real-time intra-operative information, may increase accuracy, and improves the precision of a closed-wedge HTO.

Total knee arthroplasty in stiff knees after previous infection

Between July 1986 and August 1996, we performed 32 total knee arthroplasties (TKA) on 32 patients with partially or completely ankylosed knees secondary to infection. Their mean age at surgery was 40 years (20 to 63) and the mean follow-up was ten years (5 to 13). The mean post-operative range of movement was 75.3 degrees (30 to 115) in those with complete and 98.7 degrees (60 to 130) in those with partial ankylosis. The mean Hospital for Special Surgery knee score increased from 57 to 86 points post-operatively. There were complications in four knees (12.5%), which included superficial infection (one), deep infection (one), supracondylar femoral fracture (one) and transient palsy of the common peroneal nerve (one). Although TKA in the ankylosed knee is technically demanding and has a considerable rate of complications, reasonable restoration of function can be obtained by careful selection of patients, meticulous surgical technique, and aggressive rehabilitation.

Arthroscopic synovectomy in haemophilic arthropathy of the knee

From January 1996 to January 2001, arthroscopic synovectomies were performed in 28 knees with haemophilic arthropathy. The mean follow-up period was 5 years and 11 months. Six portals (two anterior, two suprapatellar, two posterior) and a posterior trans-septal portal were used in all cases. The average Hospital for Special Surgery (HSS) knee score increased from 56.4 to 71.5 points at the last follow-up. The average frequency of haemarthrosis reduced from five times per month before operation to once per month. The amount of factor replacement decreased from a mean of 4,633xa0U to 1,505xa0U. Progression of arthritis was observed radiographically in three cases at the last follow-up. An arthroscopic synovectomy of the knee using appropriate arthroscopic portals is a useful method in treating haemophilic patients as it decreases bleeding episodes, amount of factor replacement and knee pain.RésuméDe janvier 1996 à janvier 2001, des synovectomies arthroscopiques ont été exécutées dans 28 genoux avec une arthropathie hémophilique. Le suivi moyen était 5 années et 11 mois. Six abords (deux antérieurs, deux supra-rotuliens, deux postérieurs) et un abord trans-septal postérieur ont été utilisé dans tous les cas. Le score moyen du genou de l’Hôpital pour Chirurgie Spéciale (HSS) a augmenté de 56,4 à 71,5 points au dernier examen. La fréquence moyenne d’hémarthrose s’est réduite de cinq fois par mois avant l’opération à une fois par mois aprés. La quantité moyenne de remplacement de facteur a diminué de 4,633 à 1,505 unités. Dans l’évaluation radiographique, la progression de l’arthrite a été observée dans trois cas au dernier suivi. Une synovectomie arthroscopique du genou qui utilise des abords arthroscopiques appropriés est une méthode utile pour traiter les malades hémophiliques, diminuant les épisodes de saignement, la quantité de facteur et les douleurs du genou.