Introduction and objective: Infection is one of the greatest threats in hip surgery. It is agreed that the implant should be removed. The debate remains open if one or two stage surgery is perferable. This study evaluates the two stage septic hip revison arthroplasty and compares our results with the literature.

Materials and Methods: A retrospective clinical and radiological study was performed on patients that had a two stage septic revision hip surgery. The Harris Hip Score (HHS) and the Mayo Hip Score (MHS) were applied. The ASA-Score for evaluation of preoperative morbidity was introduced. Statistical evaluation included the t–test.

Results: 40 patients with 41 primary total hip replacements underwent septic revision. 17 patients with 18 hip prostheses (8 male, 9 female) could be evaluated. 14 patients were deceased, the rest was unable to participate due to severe health problems.12 patientswith 13 hips had a primary reimplantation, 5 patients had to be left with a Girdlestone situation. The mean follow up was 52 months (4.3 years, standard error +/−28). The average age was 68 years. The mean preoperative ASA-Score was 3.24 (+/−0,75). Staph. aureus was the most common infectious agent (35%) followed by Staph epidermidis (24%) and E. coli (12%). The mean time between removal and re-implantation was 158 days. The most frequent primary preoperative indication for hip arthroplasty was osteoarthritis (62%) followed by trauma (24%) and avascular necorsis of the femoral head (14%). In 42%, the onset of ionfection was early (under 12 months after implantation), 58%% of the patients had a late onset infection. The MHS in the group who had a reimplantation was an average of 66/standard error +/−21). The patients with a Girdlestone situation had a HHS that was not significantly lower than the rest (58 in Girdlestone patients, 61 in patients with re-implantation).

Discussion: The study demonstrated that our results compare well to those of other studies. It supports the conclusion that two stage septic hip arthroplasty is still an excellent option in septic revision arthroplasty. The preoperative ASA-Score which is not routinely mentioned in other studies showed that many of our patients were critically ill. This may explain the long interval between removal and reimplantation, and it may also be of value to determine wether to re-implant at all costs. This study remarkably demonstrated that patients with resection arthroplasty did not have a significantly lower HHS than those with performed re-implantation. The resection arthroplasty may be considered a valuable solution in clinically very ill patients according to our results. If a second operation considering the ASA -score would be too risky it should be discussed if reimplantation must be achieved.

We examined 52 patients with acute Achilles tendon rupture (ATR), 43 men and 9 women, with a median age of 43 (28–68) years after percutaneous Achilles tendon repair with early functional therapy. 11 patients were treated in a cast (C) and 41 had a specially designed shoed (S). The mean follow-up was 56 (36–95) months. Patients suffering from health problems, which could affect their gait and balance (e.g. OA, spinal stenosis,…), as well as patients suffering from complications postoperatively, were excluded from the study. The mean Hannover Achilles Tendon Score was 81 (50 – 95) points (C = 81, S = 81).

Their calf muscle function studied three to eight years after treatment were found to have a significantly impaired dynamic muscle function of the calf muscles when tested in a specially constructed heel-raise test device. The Wilcoxon matched-pairs signed-ranks test showed a two-tailed P value of < 0,0001.

The average calf size was 38 (31–46,5) cm on the uninjured side and 36 (32–44,5) cm on the injured side. Only two patients had an equal calf size. Comparing the uninjured and injured side the two-tailed P value was found to be extremely significant < 0,0001.

The correlation between the maximum force and functional heel raise testing to the calf size on the injured side was weak with a Spearman correlation coefficient (r) = 0,33–38. There was no difference found between the patients treated in a cast and the patients treated in a shoe with percutaneous Achilles tendon repair and early functional therapy.

The principle finding in the present study was that the impact of an ATR is of great importance for the functional outcome than the treatment that is given. The difference in flexion strength and endurance between the injured and the uninjured side remained even after a 56 months follow-up. Therefore, calf size and functional muscle testing is a good tool to test functional outcome after Achilles tendon rupture. However, there was only a weak correlation between the size of atrophy and the amount of force reduction.

A major challenge to be faced in order to introduce cell-based therapies for bone repair into wide-spread surgical practice is to translate a research-scale production model into a manufacturing design that is reproducible, clinically effective, and economically viable. One possible means by which to achieve this goal is via a bioreactor system capable of controlling, automating, and streamlining all of the individual phases of the bone-tissue engineering process. In a first step to meeting this challenge, in this work we aimed at developing and validating a closed bioreactor system for

the efficient seeding of cells into 3-dimensional scaffolds and

Our patented bioreactor technology essentially consists of scaffolds arranged in a circular plate, which is moved in alternating directions by a linear drive unit through a cell suspension/culture medium, thus resulting in the perfusion of the cell suspension/culture medium directly through the pores of the scaffolds in alternate directions. The cultivation chamber is fully isolated from the external environment, with liquid/gas exchange achieved through aseptic interfaces.

Human bone marrow nucleated cells from 3 donors were perfused through porous ceramic discs (8 mm diameter, 4 mm thick), resulting in adhesion of the osteoprogenitor cell fraction in the ceramic scaffolds. Efficiency of cell seeding was consistently greater than 80%. Cell seeded constructs were further cultivated under perfusion for a total of 20 days, resulting in the expansion of the osteoprogenitor cells directly within the scaffold pores and maintenance of greater than 90% cell viability. Ectopic implantation of the cultivated constructs yielded abundant and reproducible formation of bone tissue, distributed throughout the scaffold pores.

The developed bioreactor provides a simple and efficient approach

to establish and maintain 3D cultures of cells into scaffolds under perfusion, and

Incorporating the bioreactor unit into a system for automated medium change and monitoring/control of culture parameters is likely to lead to the development of a closed system for the standardized production of autologous cell-based bone substitutes.

Introduction: A consecutive series of 280 total hip replacements in 261 patients using the Morscher Press-Fit Cup with a minimum follow up of 5 years was presented 1997 in the clinical orthopaedics. Now the clinical and radiological results of the same cohort after an observation time of 15 years are reported.

Material and Methods: 136 women and 125 men with 280 hip replacements have been followed up again after 15 years. The mean age at the 15 year follow up was 76 (57–90) years in women and 73 (48–90) years in men. 63 women (66 hips) and 60 men (62 hips) died during the observation period. 17 patients with 18 hips could only interviewed by phone. 121 patients with 134 hips (48%) have been clinically und radiologically followed up. The mean observation period is 14.7 (12.8–15.8) years.

Results: The clinical outcomes are excellent and good in 117 patients (97%). Nineteen femoral stems (6.8%) and 12 cups (4.3%) had to be revised: 7 due to aseptic loosening – two after 4 and 10 years in patients with rheumatoid arthritis, 4 after a SULMESH-damage after 10, 13 (2 pat.) and 14 years and 1 after big osteolyses in the zones I-III acc. to Charnley/DeLee after 13 years -, 1 due to a late infection after 9 years, 3 because of deterioration of the inlay after 11 und 12 years (2 pat.) and one owing to recurrent dislocations followed from a fracture of the greater trochanter after 9 year follow up. The 15 year survivalrate is therefore 95.5%, for aseptic loosening 97.5%. Seven hips dislocated; two patients had a closed and 5 an open reduction.

Radiological assessment revealed a complete osseoin-tegration in all 3 zones according to DeLee and Charnley in 98%. 1 cup with a continuous radiolucent line implanted after a acetabulum fracture had to be revised after a 13 year follow-up. 10 cups migrated either in the vertical or horizontal plane 2–5 mm without any progression after 2 years postoperatively. One cup had expansile osteolyses and had therefore to be revised after 13 years. With this exception there was no evidence of osteolyses in the periacetabular pelvic bone. Brooker III and IV ectopic ossifications was seen in decentration of the head of the stem as a sign of increased polyethylene-wear. Discussion: The excellent clinical and radiological results are supported by histologic investigations of 27 autopsy-specimens which show throughout a perfect osseoin-tegration with reinforcement of the osseous anchoring in the peripheral zones of the press-fit cup. We explain the wide absence of osteolyses with the disclaiming of a metal backing (preservation of elasticity and avoiding of stress shielding) and the disclaiming of using screws.

We have investigated whether control of balance is improved during stance and gait and sit-to-stand tasks after unilateral total hip replacement undertaken for osteoarthritis of the hip.

We examined 25 patients with a mean age of 67 years (sd 6.2) before and at four and 12 months after surgery and compared the findings with those of 50 healthy age-matched control subjects. For all tasks, balance was quantified using angular measurements of movement of the trunk.

Before surgery, control of balance during gait and sit-to-stand tasks was abnormal in patients with severe osteoarthritis of the hip, while balance during stance was similar to that of the healthy control group. After total hip replacement, there was a progressive improvement at four and 12 months for most gait and sit-to-stand tasks and in the time needed to complete them. By 12 months, the values approached those of the control group. However, trunk pitch (forwards-backwards) and roll (side-to-side) velocities were less stable (greater than the control) when walking over barriers as was roll for the sit-to-stand task, indicative of a residual deficit of balance.

Our data suggest that patients with symptomatic osteoarthritis of the hip have marked deficits of balance in gait tasks, which may explain the increased risk of falling which has been reported in some epidemiological studies. However, total hip replacement may help these patients to regain almost normal control of balance for some gait tasks, as we found in this study. Despite the improvement in most components of balance, however, the deficit in the control of trunk velocity during gait suggests that a cautious follow-up is required after total hip replacement regarding the risk of a fall, especially in the elderly.

We validated the North American Spine Society (NASS) outcome-assessment instrument for the lumbar spine in a computerised touch-screen format and assessed patients’ acceptance, taking into account previous computer experience, age and gender.

Fifty consecutive patients with symptomatic and radiologically-proven degenerative disease of the lumbar spine completed both the hard copy (paper) and the computerised versions of the NASS questionnaire. Statistical analysis showed high agreement between the paper and the touch-screen computer format for both subscales (intraclass correlation coefficient 0.94, 95% confidence interval (0.90 to 0.97)) independent of computer experience, age and gender. In total, 55% of patients stated that the computer format was easier to use and 66% preferred it to the paper version (p < 0.0001 among subjects expressing a preference). Our data indicate that the touch-screen format is comparable to the paper form. It may improve follow-up in clinical practice and research by meeting patients’ preferences and minimising administrative work.

Aims: We report 10-year results of the THR hybrid system. Femoral Component: Morscher-Spotorno MS-30¨, stainless steel, tapered, with- out collar with matte surface, þxed with Palakos¨+ Gentamycine bone cement. Cup: non-cemented Morscher Press-Fit Cup¨. Material and methods: A consecutive series of 123 THRs in 120 patients (75 female, 45 male) operated on between January 1990 and December 1992 were subjected to follow-up at 10 years. Mean age at surgery was 69 in women, 71 in men. No patients were lost to follow-up. 23 patients (19%) died without needing a revision, and 12 (10%) could only be inter- viewed by phone. Of the remaining 85 patients (71%) with 88 hips (70%) were available for complete evaluation. Mean follow-up was 9.8 (8.0 Ð 12.2 years).Results: Harris Hip scores were excellent and good in 84% (71 pts), moderate in 14% (12 pts) and poor in 2% (2 pts with rheumatoid arthritis). No stems or cups had to be revised. Radiographically 15 hips (13%) had femoral stem-related osteolyses Ð mostly in Gruen zones 2, 6 and 7. 8 stems subsided 2 Ð 5 mm. No infection and no acetabular osteolysis was observed. Conclusion: In 1990, the MS-30 stem was only available with a matte surface, which can impede settling and consequent maintenance of proximal load transfer to bone. Thus, although no revisions were necessary, the 13% osteolyses may relate to the matte surface. From 1994 on, the MS-30 stem has been available with a polished surface. The excellent outcome for the Morscher Press-Fit Cup corresponds to results in other series.