Masahiko Nozawa

Rotational acetabular osteotomy for acetabular dysplasia A FOLLOW-UP FOR MORE THAN TEN YEARS

Between 1986 and 1990, we carried out 55 rotational acetabular osteotomies in 54 patients with acetabular dysplasia. Five hips were lost to follow-up. Of the 50 remaining, the degenerative changes were classified according to the criteria of Tönnis as grade 0 in 23, grade 1 in 16 and grade 2 in 11. The mean age of the three men and 46 women at the time of operation was 31.8 years (13 to 53). The mean follow-up was 137 months (120 to 174). At the most recent follow-up, 48 patients had satisfactory relief from pain. There was a slight decrease in the range of movement, particularly of flexion, in 18 hips. Radiologically, all osteotomies had united satisfactorily. There was radiological evidence of improvement in degenerative changes in 13 hips (5 grade 1 and 8 grade 2). Ten deteriorated (5 grade 0, 3 grade 1, and 2 grade 2) and one required total hip arthroplasty ten years after osteotomy. The osteoarthritis in the two hips with an associated valgus osteotomy progressed. The changes in radiological indices such as the centre-edge angle, acetabular femoral head index, acetabular root obliquity and horizontal or vertical displacement of the femoral head showed no statistical difference (unpaired Students t-test) between the patients with radiological progression and those with and without improvement.

The fracture sites of atypical femoral fractures are associated with the weight-bearing lower limb alignment

PURPOSE Atypical femoral fractures (AFFs) are stress-related fractures that are speculated to associate with long-term treatment with bisphosphonates for osteoporosis. A history of AFF is a high risk factor for the development of a subsequent AFF in the same location of the contralateral femur, suggesting that a patients individual anatomical factor(s) are related to the fracture site of AFFs. In this study, we investigated the radiographs of fourteen AFFs (four bilateral fractures among ten patients) treated at six hospitals associated with our university between 2005 and 2010. The fracture site and standing femorotibial angle (FTA), which reflects the mechanical axis of the lower limb, were measured on weight-bearing lower limb radiographs. The fracture site and FTA of patients with typical femoral fractures (TFF) were compared to those of patients with AFFs. The correlations were examined using Spearmans rank correlation coefficients. The fracture locations in the femora were almost the same in the patients with bilateral AFFs. There was a positive correlation between the fracture site and the standing FTA in the patients with AFFs (r=0.82, 95% confidence interval; 0.49 to 0.94), indicating that the larger the standing FTA (varus alignment), the more distal the site of the fracture in the femur. The FTA of the patients with atypical diaphyseal femoral fracture were significantly larger compared to that of those with not only atypical subtrochanteric fractures but also TFFs. In conclusion, the fracture sites of AFFs are associated with the standing lower limb alignment, while those of TFFs are not.

Chronological changes of serum chromium levels after modern metal-on-metal total hip arthroplasty

We determined changes in serum chromium concentration every 6 months up to 3 years after implantation in 44 patients (mean age 63 (49–79) years, 35 women) who underwent modern metal-on-metal total hip arthroplasty (Metasul). The serum chromium levels increased between the first and second year after implantation (1 year: 1.05 (SD 0.76) µg/L, 2 years: 1.46 (SD 0.91) µg/L). A small increase was observed during the third year (1.61 (SD 1.31) µg/L). The clinical relevance of this finding is uncertain and should be determined in long-term studies on a large scale.

Headless Compression Screw Fixation of Jones Fractures An Outcomes Study in Japanese Athletes

Background: Internal fixation is advocated as the primary treatment for fifth metatarsal Jones fractures in athletes; however, screw insertion site discomfort and refracture can occur especially in competitive athletes. The ideal implant has not been determined. Hypothesis: Headless compression screw fixation of proximal fifth metatarsal Jones fractures is an effective treatment approach especially in competitive athletes. Study Design: Case series; Evidence level, 4. Methods: We studied 60 athletes treated surgically with a headless compression screw for fifth metatarsal Jones fractures (mean age, 19 years). The mean follow-up time was 178 weeks. We evaluated the clinical and radiographic outcomes of headless compression screw fixation of Jones fractures. Results: All athletes returned to full activity. The mean time to start running after surgery was 6.3 weeks (range, 3-12.7 weeks), and the mean time to full activity after surgery was 11.2 weeks (range, 6-25 weeks). One athlete suffered a delayed union, which healed uneventfully. One athlete suffered a nonunion and underwent reoperation for a screw exchange to an autogenous bone graft harvested from the iliac crest. No screw breakage was reported. No athlete suffered a refracture or discomfort in the screw insertion site. Conclusion: Headless compression screw fixation of fifth metatarsal Jones fractures provided excellent results, allowing athletes to return to full activity without both screw insertion site irritation and clinical refracture.

Seven Years of Chronological Changes of Serum Chromium Levels After Metasul Metal-On-Metal Total Hip Arthroplasty

Although many authors have reported the serum concentrations of metal ions in patients who had metal-on-metal coupling prostheses, most of the studies were not longitudinal, and the follow-up periods were short. We evaluated the longitudinal changes of serum chromium levels in 44 patients who had undergone unilateral metal-on-metal total hip arthroplasty for a minimum of 7 years postoperatively. Although there was a consistent increase in the mean serum chromium level until 3 years after implantation, there was little difference in the levels from years 3 to 7 postoperatively. Although the serum chromium concentration was low throughout postoperative follow-up for 7 years in about 25% of patients, the serum chromium level stayed high or showed gradual elevation in 16.3% of our patients.

The new technique of precise insertion of lag screw in an operative treatment of trochanteric femoral fractures with a short intramedullary nail

In order to reduce the incidence of cut-out, which is one of the serious postoperative complications of trochanteric femoral fractures, we paid special attention to the placement of lag screw in the femoral head. As a result, we devised a new technique that allows insertion of the lag screw at the first attempt into the optimal position on both planes, inferior half on the antero-posterior view and exactly central on the lateral view, without the need for any special devices other than the basic original set, using a trochanteric nail. For this technique, we have evaluated the proximal femoral profile under image intensifier, on the true lateral view projected parallel to the axis of the femoral neck and not on the conventional lateral view (Lauenstein view) with the projection parallel to the axis of the femoral shaft in a coronal plane. With the X-ray beam lying in the same plane with the targeting device including the nail and the guide sleeve, the guide pin is intended to pass through the guide sleeve and the middle of shadow of the proximal end of the targeting device, so that it can be inserted in the optimal position without fail, aligned with the middle axis of the femoral head. The deviation angle between the axes of the lag screw and the femoral head was measured on every postoperative lateral radiograph. The mean deviation angle of 1.6 degrees in the 39 fractures after the introduction of the new insertion technique was compared with 4.8 degrees in the 44 fractures before the introduction, which showed a significant difference between these groups (p<0.0001, Welchs t-test). When the lag screw can be placed exactly in the centre of the femoral head on the true lateral view, it can be set forward as closest to articular surfaces as possible on the postero-anterior view without a risk of penetration, so that the tip-apex distance could be easily achieved under 20mm, which leads to a reduction of postoperative cut-outs. This technique can be applied in other similar trochanteric nails, which gives them an advantage over the sliding hip screws.

Rotational acetabular osteotomy for severely dysplastic acetabulum.

Abstract The operative procedures chosen for arthrosis with severe acetabular dysplasia vary among orthopaedic surgeons. We operated on 250 hips using the rotational acetabular osteotomy (RAO) method of Ninomiya and Tagawa [8]. In this report, we describe the technique of RAO and the results of this procedure in patients with severely dysplastic hips. Among the 250 hips, there were 6 which were classified as Severin group V. In those hips, the CE angle was less than 0°, and the femoral head showed superolateral subluxation. After acetabular osteotomy with straight and curved osteotomes, smooth inferolateral rotation could be done in all cases. At the latest follow-up symptoms were improved remarkably, especially pain. Radiographically, adequate coverage of the femoral head was achieved and joint congruence improved in all 6 hips.

Reinfusion of unwashed salvaged blood after total knee arthroplasty in patients with rheumatoid arthritis

Autotransfusion with unwashed salvaged blood (USB) is effective for avoiding allogeneic blood transfusion (ABT) in patients undergoing total knee arthroplasty (TKA). We performed a retrospective study to determine the percentage of patients receiving ABT and the volume of postoperative blood drainage after introduction of autotransfusion with USB for patients with rheumatoid arthritis (RA) undergoing TKA. In 100 patients without autotransfusion (group 1) and 100 patients receiving autotransfusion of USB (group 2), we compared the number of patients who required ABT, as well as the postoperative drainage volume, ABT volume, and autotransfusion volume. In group 1, 83% of the patients received ABT, while only 47% received ABT in group 2, and there was a significant decrease (p < 0.001). However, the postoperative drainage volume was significantly increased in group 2 (p < 0.001).RésuméL’utilisation du sang récupéré en post-opératoire (USB) est une technique qui permet d’éviter la transfusion de sang autologue, chez les patients ayant bénéficié d’une prothèse totale du genou. Nous avons réalisé une étude rétrospective afin de déterminer le pourcentage de patients recevant le sang récupéré et le volume nécessaire. Nous avons réalisé cette étude pour déterminer le pourcentage de patients recevant une transfusion en rapportant ceci au volume de sang récupéré dans les drains après réalisation d’une auto-transfusion, ces patients étant porteurs d’une arthrite rhumatoïde. Chez 100 patients sans auto-transfusion (groupe 1) et 100 patients ayant bénéficié d’une auto-transfusion (groupe 2), nous avons comparé le nombre de patients ayant bénéficié d’une nouvelle transfusion ainsi que le volume du sang récupéré dans les redons, volume de sang réinjecté et l’importance de l’auto-transfusion. Dans le groupe 1, 83% des patients ont reçu une transfusion alors que seulement 47% en ont eu besoin dans le groupe 2. Il existe une différence significative entre ces deux groupes (p < 0.001). Cependant la perte sanguine dans les redons était significativement plus important dans le groupe 2 (p < 0.001).

Activation of fibrinolysis by reinfusion of unwashed salvaged blood after total knee arthroplasty

In 19 patients with RA and 20 with OA who underwent autotransfusion with unwashed salvaged blood (USB) after total knee arthroplasty, we performed serial measurement of D-dimer, FgDP, t-PA, and PIC in the plasma and salvaged blood. The PIC level at the completion of salvaged blood transfusion was closely correlated with the volume of USB reinfused in the RA group (p<0.001). The t-PA level of salvaged blood showed a significant positive correlation with the total volume of postoperative drainage in both the RA and OA groups (p<0.05). The increase of total postoperative drainage associated with reinfusion of USB is largely caused by an increase of t-PA in the salvaged blood.

Stress fractures of the femoral neck in child with open capital femoral epiphysis.

Stress fracture of the femoral neck has been considered a typical injury of two age groups: active youths and elderly people with osteoporosis. Its occurrence in children with an open capital femoral epiphysis is rare, and only 11 cases have been reported. Here we report two cases, in a 12-year-old boy and a 5-year-old girl (among the youngest patients on record). This fracture can be classified as a compression fracture or a tension fracture. Although tension fractures are not uncommon in military recruits and young athletes, all 13 cases (including our two cases) of femoral neck stress fracture associated with an open capital epiphysis were compression fractures that were treated conservatively.