Bone preserving hip arthroplasty devices are appealingfor use in young patients because their high-demand activities and extended lifetimes makes the prospect of multiple revisions a reality. Therefore prostheses which ensure a straightforward revision with a low complication rate and good clinical outcome are favourable for young and active patients.

Modern hip resurfacing serves these conditions and shows very good mid-term and now longer term (10 and 13 years) results especially in osteoarthritis. With other diagnoses like avascular necrosis, deformities of the femoral head in m. Perthes or slipped femoral epiphysis (SUFE), or in large bone cysts and erosive arthritis the bone stock of the femoral head gives insufficient support to the femoral component. In these conditions the alternative to a resurfacing procedure had been a stemmed total hip arthroplasty (THA).

The Birmingham Mid Head Resection device (BMHR; Smith&Nephew Orthopaedics) is an alternative to resurfacing and to a stemmed THA. The BMHR device consists of an uncemented short stem made of titanium alloy and a large diameter cobalt-chrome head. The stem does not enter the femoral canal thus facilitating future revisions. The metal-on-metal bearing is the same as in resurfacing. The instrumentation allows switching from a planned BHR to the BMHR. The BMHR uses the unique anatomy of the head neck junction to prepare internally a cone that matches the frustoconical section of the BMHR stem. Thus a cement free press fit can be achieved. This maintains anatomical load transmission and avoids osteopenia of the proximal fenur.

Since 2006 we have performed 662 BMHR implantations. The indications were osteoarthritis in about 70%, dysplasia in 20%, AVN 5,5%, posttraumatic OA in 3%, SUFE and m. Perthes in 1%. Complications occured in 3,2%. Fractures of the femoral neck occured in 8 patients, 4 of them caused by technical errors in the beginning, 3 because of higher risk indication. All revisions were performed successfully and the cup was retained. Low grade infections in 2 cases with one stage revision and 3 unstable cups needed to be reinserted. All revisions were successful. One early dislocation was treated by closed reduction, another remained unstable and was treated by THA. In conclusion we continue to use the BMHR to bridge the gap between resurfacing and stemmed THA because the complications we experienced are not inevitable and had become very rare with our growing experience.

Ouery: Matrix-coupled autologous chondrocyte transplantation (MACT) has become increasingly widespread in the therapy of cartilage defects. The objective of this controlled prospective study was to examine the mid-term results of MACT compared to those of Microfracturing (MF) for the treatment of cartilage defects in the knee joint and to determine possible advantages or disadvantages of the two methods.

Method: In order to compare the two treatment methods, 40 patients with discrete cartilage defects were treated with MACT and 40 with MF between 4/01 – 4/03. As inclusion criterion, the patients had a chondral defect of at least 1.5 cm and as exclusion criterion, there could be no additional cartilage damage in the other areas of the knee. MRI examinations were performed preoperative (T2 gew. TSE-Sequence, fetts. FLASH-3D) and could be repeated after 6 and 12 months. Knee joint function, the activity level and the patient’s quality of life were evaluated in both groups pre- and postoperative using the modified Cincinnati Score and the Tegner Activity Index.

Results: There was significant improvement in the scores used for the study in both the MF group and the MACT group. Comparison of the two groups revealed significantly greater clinical improvement in the MACT patients than in the MF patients (3.8 point increase MACT versus 2.6 point increase MF in the Cincinnati Score). Taking the size extent of the treated cartilage damage into account, there was, however, no relevant difference in defects less than 2,5 qcm.

Conclusion: The study could demonstrate that both methods are successful in treating localized cartilage damage in the knee joint. Comparison of the two forms of therapy showed a greater extent of improvement in the MACT group. However, classification by the size of the defect revealed that this effect was relevant only in larger defects, so that the size of the defect should be a decisive criterion for the selection of therapy.

Query: In the past few years, chevron osteotomy has become more widespread in the treatment of mild Hallux valgus deformities thanks to its low rate of complications and excellent results. The results in moderate to severe deformities are not as convincing, depending on the surgical procedure used. The objective of this study was to examine the influence which the choice of surgical procedure and thus the osteotomy has on the clinical, radiological and pedobarographic results in the forefoot.

Method: In a prospective study, we examined the surgical results of 140 feet treated between August 2004 and March 2005 in our clinic for moderate Hallux-Valgus deformity. In 70 patients, Ludloff osteotomy and in 70 the Scarf osteotomy was selected as the method. The patients underwent pre- and postoperative clinical, radiological and pedobarographic examination. In addition, patient satisfaction was determined using the Kitaoko Forefoot Score. Indication for performance of the osteotomy was a Hallux-Valgus deformity up to an intermetatarsal angle (IMA) of 17°.

Results: The mean preoperative IMA was 14.5 °, the Hallux-Valgus angle (HVA) 31.3°. The IMA could be improved by Scarf osteomy on average by 7.6°, by Ludloff osteotomy by 8.1°. With suitable plantarisation of the 1st metatarsal head, better and more even pressure distribution in the forefoot could be achieved with both surgical procedures and the load peaks reduced overall. The complication rate was somewhat lower overall in the Scarf osteomy.

Conclusion: Both the Scarf osteotomy, and the Ludloff ostetomy enable achieving of good results in moderate deformity. The extent to which one procedure should be preferred over the other could not be determined. Both procedures have advantages as well as disadvantages. Further attention to this area of Hallux-valgus surgery is definitely needed to meet the higher demands of the patients.

Query: The means for treating Osteochondrosis dissecans (OD) of the knee joint in adolescents remains today a matter of controversial discussion. Not only the different treatments, whether purely conservative or one of the various surgical procedures, are rated differently with respect to their benefit, but also the question of the right time to operate is not easy to answer. The objective of this prospective study was to examine the long-term results of a bioabsorbable fixation system in the treatment of OD and to determine possible relationships between the baseline conditions, such as stage of disease, patient’s age, severity or localization and the results in each case.

Method: Between 1995 and 2005, 312 patients aged 7 to 19 years with Osteochondrosis dissecans were treated by means of arthroscopic operation on the knee joint. In 257, fixation using ethipins could be performed, the dissecate had to be removed in 31 patients. An MRT was performed preoperative in all patients, the knee joint function, activity level and patient’s quality of life were evaluated postoperative using the modified Cincinnati Score, the Tegner Activity Index and the Lysholm Score.

Results: 255 of the 312 patients were available to follow-up over a longer period (Ø 7.9 years). The Lysholm Score for all patients 5 years after surgery was 87.6 points, after 10 years 76.5. Classified by baseline stage, it was found that the postoperative course was clearly better in those patients in whom fixation was required. Moreover, an early stage of OD and younger patient age were prognostically favorable factors. The MRT follow-up examination showed re-integrated vital cartilage areas without signs of fixation residuals in patients in whom fixation was performed.

Conclusion: Surgical treatment of Osteochondrosis dissecans brings different results depending on the stage of the disease. Moreover the results depend on patients age, location of the defect, duration of symptoms. If fixation of the dissecate using bioabsorbable pins is successful, the long-term results achieved are good to excellent. Overall, the data obtained justify an early decision for a surgical procedure in the treatment of Osteochondrosis dissecans of the knee joint in children and adolescents.

Query: Persistent complaints following implantation of a knee prosthesis are often a problem which is hard to overcome. On the one hand, general diagnostics do not reveal the cause of the complaints, on the other, pain symptoms in connection with deficient patella control cannot always be attributed to insufficient equilibrium of the soft tissues. In this prospective study, the rotation of the components was examined in connection with the pain described by 49 patients.

Method: The rotation of the prosthesis components was examined by means of axial CT scans in 49 patients with the complaint symptoms described above and without signs of loosening or malpositioning at the frontal or sagittal level. The results were set in relation to clinical symptoms, the Knee Society Score and a VAS.

Results: A direct relationship was found between the extent of the added inner rotation malpositioning of the components and a deteriorated Knee Score. No difference in the pain score in dependence on the extent of improper implantation could be observed. Incorrect tibial rotation was responsible in particular for patellar lateralization, subluxation or tipping.

Conclusion: The correlation between inner rotation malpositioning and deficient patellar control or signs of instability underlines the importance of intraoperative rotation adjustment in the prevention of knee pain. In unclear knee pain following knee endoprosthesis implantation, performance of a CT to determine the component rotation is indicated. If there is a rotation malpositioning, correction in a revision procedure should be considered.

Query: The treatment of discrete but advanced cartilage damage to the knee joint, such as in osteonecrosis in patients older than 45 years, has not been satisfactorily resolved to date. The objective of this prospective study was to investigate the utility of a minimally-invasive unicondylar surface replacement system and to record the first clinically-obtained results.

Method: We are reporting on the results of the first 19 operations of discrete knee joint defects performed in our clinic since October 2004 using the Arthrosurface System. The Arthrosurface System consists of specially-preformed convex implantate dowels and an adapted integrative fraise system for handling the femurcondylus. The knee joint function, the activity level and the patient’s quality of life were evaluated pre–and postoperative using the Knee Society Score, the Tegner Activity Index and the Lysholm Score.

Results: In the operating room, the system was impressive in its utility. No implantate-related complications have occurred in the short follow-up time thus far. In the early postoperative phase, the patients achieved rapid increase in their activity level which paralleled the reduction in pain relief attained.

Conclusion: The Arthrosurface^® System shows beneficial properties for treating localized but advanced cartilage damage to the knee joint of patients older than 45 years of age. In particular, it enables arthroscopically-supported minimally-invasive implantation. Intact structures are thus not damaged and the patient rehabilitation is rapid.

Purpose of Study: Once the decision is made to treat an acute Achilles tendon rupture by surgical procedure, the surgeon is confronted with numerous operative techniques. After Ma et al. have described the percutaneous suture, it exists a alternative to the open method. The ad- and disadvantages of both methods or of the conservative treatment are often discussed. It should be inverstigated how the results of operative treatment by percutaneous repair are and if there is a possibiltiy to improve them by the use of a modified technique.

Method: The study includes 76 patients with Achillles tendon rupture, who underwent a percutaneous repair from 1999 to 2003 in our department. The patients were examined on average 26 months. In changing the original technique we used a straight needle for guiding the suture transversly through the wound. In addition the way how the neeedle is pushed into the tendon to adapt the stumps is modified.

Results: All patients could be examined after the operation. The patients, who have done sports before the accident were able to return after the healing time. We saw no superficial or deep wound infection. We had 4 patients with sural nerve injuries, three resolved in six to nine months. There was one patient with a rerupture, who underwent open surgical repair.

Conclusion: The percutaneous suture offers an interesting alternative method to the standard open repair in the treatment of Achilles tendon rupture.

Purpose of the study: Autologous chondrocyte transplantation has become in the last years more and more popular for the treatment of chondral knee lesion. The standard procedure has good result, however important disadvantages represent the difficulty to manage liquid chondrocyte culture solution and the necessity to create the hermatic periosteum suture.The aim of the our study was to investigate the short time results of a matrix-induced chondrocyte transplantation (MACT) for treatment cartilage defects in the knee und to analyse ad- or disadvantages.

Method: Since June 2001 we use for the autologous chondrocyte transplantation (ACT) instead of a periosteum flap the 3-dimensional matrix or resorbarble fleece. 35 patients with defects in cartilage of the knee have been treated so far. Average defect size was 4,8 qcm, all patients had a follow up with clinical investigations and MRI studies. The results were evaluated by different scores.

Results: 33 of 35 patients were after six months satisfied with the operation result or justed it more better. All of the subjective or objektive parameters of the different scores were improved after one year. The clinical outcome was good in the follow-up.

Conclusion: In the follow up the results can be compared with the one found in literature of the standard periost method. The matrix-induced chondrocyte transplantation has the advantage, that no periost flap is needed and that the chondrocyte culture is not liqiud. The first results are promising.