Introduction: Veldhuizen (2002) developed a new flexible Scoliosis-Brace for effective curve correction in Idiopathic Scoliosis. This new Brace is characterised by a improved cosmetic appearance and wearing comfort compared to conventional ortheses (Cheneau, Boston).

We investigated the effectiveness of the TriaC™-Brace regarding the primary curve correction in Idiopathic Scoliosis (IS).

Materials and Method: Following the guidelines given by Veldhuizen (2002) we have treated 20 patients (15 girls, 5 boys, average age: 12,43) with diagnosis of IS (King I:6, King II:4, King III:8, King IV:1, lumbar:1) with the TriaC™-Brace from 2002–2004.

At the beginning of the therapy with the new orthesis the Risser sign was 2,68 at an average.

The daily wearing time was instructed with 22–23 hours.

Lumbar curves showed an average cobb angle of 26,1 degrees (standard deviation=8,6) and thoracic curves of 24,4 degrees (standard deviation=6,5).

The radiological assessment of primary curve correction (cobb-angle) was performed 6,2 weeks after the beginning of the therapy (anterior posterior radiograph of the spine in standing position with orthesis).

Further radiological controls were performed every six months. We evaluated the wearing time, comfort and leisure activity with a valid scoring system (Quality of Life Profile for Spine Deformities).

The overall mean wearing time of the Triac™-Brace was 14,7 months.

Results: For lumbar curves (n=12) we measured a primary correction of 9,9 degrees (40%; statistically significant, t-test, p=0,01) and for thoracic curves (n=20) of 2,2 degrees (8,4%; not statistically significant, t-test, p=0,42).

A insufficient primary curve correction (defined as < 30% of the initial cobb-angle) was observed in 16 thoracic curves (89%) and in 4 lumbar curves (30%).

An increasing correction during the therapy as reported by Veldhuizen (2002) could not be observed.

There was a curve progression of at least 5 degrees of the cobb-angle in 4 cases.

The evaluation by the scoring system (response in 85%) resulted in a high score for cosmetics (4,2/5) and mobility of the back (4,6/5). The wearing time was reported by 90% of the patients with 22–23h.

Conclusion: We do not recommend the conservative therapy of thoracic or double curves (King III, King I and II) with the TriaC™-Brace.

Larger studies are necessary to investigate the effectiveness of the orthesis in lumbar curves. The improved wearing comfort and cosmetics are a potential advantages of this new orthesis.

Introduction: The aim of the study is to evaluate different operation techniques after total knee arthroplasty (TKA). Functional outcome as well as objective results in activity (activity monitor) after minimal invasive TKA was compared with functional outcomes after a standard midvastus approach.

Purpose: The primary purpose of the present study was to determine the difference between two approaches in surgery of total knee arthroplasty. Is there a difference in outcome between a standard and a minimal invasive surgery because of less muscle damage and soft tissue stress?

Material and methods: The study includes two groups with 20 patients each (MIS group versus standard group) The patients are investigated at six different times: 1 day preoperatively as well as on 1., 3., 7. day postoperatively as well as 6 and 12 weeks after surgery. We used the AMP 331 (Dynastream Innovations, Inc., Cochrane, AB) a new ankle-mounted activity monitor. Step count, distance travelled, walking speed, step length, cadence and energy expenditure were measured. 1, 6 and 12 weeks postoperatively patients got the device for 5 days.

Results: The average age in the standard group was 66.4 years and for the MIS group, 66,8. The MIS group has been shown a sig. higher KSS Score versus standard group in all follow up visits. Standard group has shown a slight higher blood loss and higher values of muscle specific lab parameter (Creatininkinase and Myoglobin). The Activity Score was better in the MIS group in comparison to the standard group. These results also mirrored the data from the activity monitor (AMP 331, Dynastream Innovations, Inc., Cochrane, AB). The average walking speed at 1, 6 and 12 weeks was sig. (p< 0.05) better than in the standard group. Same trend we have seen in cadence, step length and steps per day.

Conclusion: This study shows that patient who underwent minimal invasive surgery in knee arthroplasty have an better early outcome after surgery in activity and function because of saving muscle structure and minimise soft tissue stress.

Study design: Cross-sectional study of 10 patients to measure the serum levels of cobalt and chromium after TDA.

Summary of Background Data: In total hip endoprosthetics and consequently for TDA (total disc arthroplasty), metal-on-metal combinations are used with the aim of reducing wear debris. In metal-on-metal TDA the release of metal ions has until now been secondary to the main discussion.

Objectives: To investigate the release of cobalt and chromium ions into the serum following implantation of the metal-on-metal MaverickTM type artificial lumbar disc.

Materials and methods: We investigated the serum cobalt and chromium concentration following implantation of 15 Maverick™ TDAs (monosegmental L5/S1 n=5; bisegmental L4/5 and L5/S1 n=5; average age = 36.5 years). 5 healthy subjects (no metal implants) acted as a control group. The measurements of the metals were carried out using the HITACHI Z-8200 AAS polarized Zeeman atomic absorption spectrometer after an average of 14,8months.

Results: The concentrations of cobalt and chromium ions in the serum amounted on average to 4.75μg/l (standard deviation 2,71) for cobalt and 1.10μg/l (standard deviation 1,24) for chromium. Compared to the control group, both the chromium and cobalt levels in the serum showed significant increases (Mann-Whitney Rank Sum Test, p=0.0120). At follow-up the Oswestry Disability Score was on average significantly decreased by 24.4 points (L5/S1) (t-test, p < 0.05) and by 26.8 points (L4-S1)(t-test, p < 0.05). The improved clinical situation is also represented by a significant decrease of the Visual Analog Pain Scale of 42,2points after the follow-up (t-test, p< 0,05).

Conclusion: Significant systemic release of Cr/Co was proven in the serum compared to the control group. The concentrations of Cr/Co measured in the serum are similar in terms of their level to the values measured in THA metal-on-metal combinations or exceed these values given in the literature. Long-term implication of this metal exposuere in unknown and should be studied further.

MIS techniques in hip arthroplasty above all have the objective to shorten the rehabilitation period by suitable preparation. A modified Watson-Jones approach through the muscle interval between the middle gluteus and the tensor muscle of fascia latae via a 6 – 8 cm anterolateral skin incision provides a good overview to the preparation. The risk of damaging the lateral femoral cutaneous muscle is relatively low when a suitable incision technique is employed. The use of special instruments decisively decreases the risk of preparation errors, extension damage of the skin nerve and misimplantation of prosthesis components. Back-positioning of the patient on the operating table has clear advantages compared to lateral positioning. When the stem is prepared the proximal femur can be brought into the surgery area by re-positioning the leg under the contralateral leg without overstretching the leg which in turn might lead to extension damage of the femoral nerve. When the implant is chosen, short stems provide minimum bone loss and the advantage of a varic access to the bone, which makes the preparation substantially easier and additionally spares the soft parts. Straight stem prostheses may also be implanted using this method, however, here the danger of an extension damage of the femoral nerve is given by the hyperextension of the leg during preparation. A further common minimal invasive approach is ventral access between the tensor muscle of fascia latae and the sartorious muscle. Here in particular with muscular patients the danger of damaging the rectus femoris by post-operative bleeding is given. The skin is incised in alignment with the lateral femoral cutaneous muscle, which is to be displayed imperatively to be spared. For stem preparation an even more disadvantageous hyperextension of the leg is required. The two-incision-technique where the straight stem is implanted by a gluteussnip – comparable with femur nailing – only provides a very bad view at the proximal femur. Here there is a greater risk of an unnoticed bone fissure when cement-free pressfit stems are used. The advantage of this technique lies in minor hyperextension of the leg for preparation.

Minimal invasive hip arthroplasty provides advantages for the patients above all in the early rehabilitation stage. However, the total concept is to be “minimal invasive” and skin incision, sparing of soft parts, choice of prosthesis and duration of surgery are to be considered.

Aim: The LPS Mobile Flex was designed to adress a physiological range of motion after TKA. Methods: We compared 40 LPS and 40 LPS Flex knees in a prospective randomized study. The average age was 64.9 (60–70) years in the LPS group (26 female/14 male) and 63.6 (54–70) years in the LPS Mobile Flex group (27 female/14 male. The surgeries were performed by two surgeons. Same approaches and techniques were used to adress the ßexion capacities. No patient was lost to the follow up. The outcome was clinical and radiological investigated and comprised after 3 month. For the clinical comparison the American knee society score was used. Results: The average range of motion in the LPS group was 110û (90–150û) after 3 month (preop. ßexion was 111û (85–140û). At the same time the average range of motion in the LPS Flex group was 125û (95–150) (preop. ßexion was 108û (80–130). After 3 month the ßexion ability was signiþcantly improved by 15û using the LPS ßex. According the knee score there were no significant differences between the groups besides the range of motion. Also radiologically there were no differences between the groups. 92,5% of the patients in each group showed central tracking in the patellofemoral groove in the sunrise view. Conclusions: The LPS Mobile Flex is an alternative to improve knee function and make the knee more physiological after TKA. To take advantage of the design features it requires a proper surgical technique and a proper patient selection.