Bernd Füchtmeier

Development of new reconstructive techniques: use of Integra in combination with fibrin glue and negative-pressure therapy for reconstruction of acute and chronic wounds.

Large wounds resulting from severe injuries are generally treated with extended reconstructive operations (e.g., free flaps), which are accompanied by long hospitalizations and risks of infection, thrombosis, and flap loss. Integra is a collagen template that can be used for reconstruction of defects. The take rate and the rate of infection are essential for the successful use of Integra (Johnson and Johnson, Hamburg, Germany). Whether the take rate and integration of Integra could be improved with the use of fibrin glue and negative-pressure therapy was assessed. Between January of 2002 and December of 2002, patients with large defects who underwent Integra grafting for reconstruction were randomly divided into groups receiving either a new treatment with fibrin glue-anchored Integra and postoperative negative-pressure therapy or conventional treatment. Demographic features, cause of the wound, location of the wound, take rate, complications of Integra coverage, time from Integra coverage to skin transplantation, and functional and aesthetic results were assessed. Twelve patients (with similar group distributions with respect to sex, age, and location and cause of the injury) were included in the study. The take rate was 78 ± 8 percent in the conventional treatment group and 98 ± 2 percent in the fibrin/negative-pressure therapy group (p < 0.003). The mean period from Integra coverage to skin transplantation was 24 ± 3 days in the conventional treatment group but only 10 ± 1 days in the fibrin/negative-pressure therapy group (p < 0.002). The decrease in the interval between coverage with Integra and skin transplantation resulted in shorter hospital stays. The use of fibrin glue and negative-pressure therapy in combination with Integra could shorten the period from coverage to integration, which would be beneficial in terms of decreased risks of infection, thrombosis, and catabolism. Therefore, it is suggested that Integra be used in combination with fibrin glue and negative-pressure therapy to improve clinical outcomes and shorten hospital stays, with decreased risks of accompanying complications.

Clinical and morphological conditions in capsular contracture formed around silicone breast implants.

Background: A study was performed to investigate histological changes in capsules formed around silicone breast implants and their correlation with the clinical classification of capsular contracture defined by the Baker score. For histological classification, the authors used the classification introduced by Wilflingseder, which identifies four grades of contracture. Methods: The study included 24 female patients (average age, 40 ± 12 years) with capsular contracture after bilateral cosmetic breast augmentation with smooth silicone gel implants (Mentor, Santa Barbara, Calif.). The Baker score was determined preoperatively for each patient. Samples of capsular tissue were obtained from all patients for histologic and immunohistochemical analyses. Capsular thickness, age of the collagen fibers, presence of synovia-like metaplasia on the inner surface of the capsule, number of histiocytes, giant cells, and other inflammatory cells, amount of silicone, foreign body granulomas, and capsule calcification were evaluated. Results: There was a positive correlation between capsular thickness (p < 0.05) and Baker score. Silicone-containing deposits were found in all four histological capsule types. A trend toward greater capsular thickness was documented in patients with severe inflammatory reaction. These patients also had more clinical symptoms. Greater capsular thickness was associated with a higher number of silicone particles and silicone-loaded macrophages in the peri-implant capsule. Conclusions: The authors demonstrated a positive correlation (p < 0.05) between the clinical classification (Baker score I to IV) and the histological classification introduced by Wilflingseder (Wilflingseder score I to IV). An exact histological classification is needed to describe precisely the morphological changes in capsular contracture.

Clinical comparison of the second and third generation of intramedullary devices for trochanteric fractures of the hip—Blade vs screw

With industrial societies getting older the incidence of femoral fractures is increasing. Complication rates up to 20% have led to a continuous improvement of intramedullar nailing systems and the third generation of implants is in clinical application. They seem superior to the second generation. But as clinical data is still fragmentary, we wanted to compare a second generation implant, the Proximal Femur Nail with three devices of the third generation: the Gleitnagel, Trochanter Fixation Nail and the Proximal Femur Nail Antirotation with a clinical study. We analysed whether fracture reduction and implant position could possibly be indicators for implant complications. Patients with a trochanteric fracture type A1-A3 (AO/ASIF classification) admitted at the department of traumatology Augsburg were enrolled. Postoperative X-rays were analysed in the matter of fracture reduction for the fracture gap, the Garden Alignment Index and for the matter of implant position in the femur head with the cleaveland zones and the Tip Apex Distance. 322 patients were enrolled. Most frequent was the A2 (n=240) and the A3 type of fracture (n=80) followed by A1 (n=29). Time to hospital discharge was 17 days (9/25), 12 patients died (3.2%). The complication rate (cutting out) in the third generation was lower (2.5-7%) than in the second generation (14%). The postoperative range of mobilisation compared to the old social status was in the groups with 34% similar after 3 months. The third generation nails are safe and reliable implants. Compared with second generation devices, fewer complications are observed. A correlation might be seen in the postoperative X-rays between the fracture reduction or implant position and implant related mechanical complications (cutting out).

Is the rotation of the femural head a potential initiation for cutting out? A theoretical and experimental approach

BackgroundSince cut-out still remains one of the major clinical challenges in the field of osteoporotic proximal femur fractures, remarkable developments have been made in improving treatment concepts. However, the mechanics of these complications have not been fully understood.We hypothesize using the experimental data and a theoretical model that a previous rotation of the femoral head due to de-central implant positioning can initiate a cut-out.MethodsIn this investigation we analysed our experimental data using two common screws (DHS/Gamma 3) and helical blades (PFN A/TFN) for the fixation of femur fractures in a simple theoretical model applying typical gait pattern on de-central positioned implants. In previous tests during a forced implant rotation by a biomechanical testing machine in a human femoral head the two screws showed failure symptoms (2-6Nm) at the same magnitude as torques acting in the hip during daily activities with de-central implant positioning, while the helical blades showed a better stability (10-20Nm).To calculate the torque of the head around the implant only the force and the leverarm is needed (N [Nm] = F [N] * × [m]). The force F is a product of the mass M [kg] multiplied by the acceleration g [m/s2]. The leverarm is the distance between the center of the head of femur and the implant center on a horizontal line.ResultsUsing 50% of 75 kg body weight a torque of 0.37Nm for the 1 mm decentralized position and 1.1Nm for the 3 mm decentralized position of the implant was calculated. At 250% BW, appropriate to a normal step, torques of 1.8Nm (1 mm) and 5.5Nm (3 mm) have been calculated.Comparing of the experimental and theoretical results shows that both screws fail in the same magnitude as torques occur in a more than 3 mm de-central positioned implant.ConclusionWe conclude the center-center position in the head of femur of any kind of lag screw or blade is to be achieved to minimize rotation of the femoral head and to prevent further mechanical complications.

Treatment of long bone defects and non-unions: from research to clinical practice

The treatment of long bone defects and non-unions is still a major clinical and socio-economical problem. In addition to the non-operative therapeutic options, such as the application of various forms of electricity, extracorporeal shock wave therapy and ultrasound therapy, which are still in clinical use, several operative treatment methods are available. No consensus guidelines are available and the treatments of such defects differ greatly. Therefore, clinicians and researchers are presently investigating ways to treat large bone defects based on tissue engineering approaches. Tissue engineering strategies for bone regeneration seem to be a promising option in regenerative medicine. Several in vitro and in vivo studies in small and large animal models have been conducted to establish the efficiency of various tissue engineering approaches. Neverthelsss, the literature still lacks controlled studies that compare the different clinical treatment strategies currently in use. However, based on the results obtained so far in diverse animal studies, bone tissue engineering approaches need further validation in more clinically relevant animal models and in clinical pilot studies for the translation of bone tissue engineering approaches into clinical practice.

Mid-Term Results of 121 Periprosthetic Femoral Fractures: Increased Failure and Mortality Within but not After One Postoperative Year

Periprosthetic femoral fractures are associated with high failure rates and mortality, particularly within one postoperative year. However, mid-term results related to this issue are lacking. Thus, we performed a retrospective follow-up evaluation. Between 2007 and 2012, we treated a total of 121 consecutive patients for periprosthetic femoral fractures. After a mean of 57.2 postoperative months, we documented a total surgical revision rate of 16.5% within the first year, and the one-year mortality rate was 13.2%. Between one year and up to 7.3 postoperative years, only one surgical revision was necessary, and the mortality rate also decreased. No significant factors related to surgical revisions were detected. However, the initial hip fracture, older age, higher ASA score and dementia were associated with a higher mortality rate.

The treatment of dislocated humeral head fractures with a new proximal intramedullary nail system

A new proximal humerus nail (Sirus) for the treatment of proximal humerus fractures has become available. This paper presents the clinical and radiological outcome of the first collective study of 36 patients. Evaluation was performed prospectively. An antero-acromial approach was used for all patients. Three fixed-angle screws were inserted in a locking technique. Thirty-six fractures were fixed with the Sirus nail. These were dislocated 2- and 3-part fractures as described by Neer (J Bone Joint Surg 52:1077–1089). Outcomes were evaluated using the Constant score. Of the 36 patients evaluated 23 had sustained a 2-part fracture and 13 a 3-part fracture. The average age at surgery was 71.2 years (range, 30–93). In 75% of the cases, good to very good outcomes were achieved. Outcomes were satisfactory in 13.8% of the cases. Twenty-five fractures were treated in a closed technique. Average operating time was 41 minutes (range, 19–106) with a fluoroscopy time of 0.6 minutes (range, 0.4–2.6). Secondary fragment dislocation occurred in two cases. After 12.1 months the average Constant score was 79.2 (range, 46–100). Initial clinical experience with the Sirus nail indicates that the procedure is straightforward and has a low complication rate. Functional outcomes are predominantly good to very good. Large fragments of the greater tuberosity and 4-part fractures are beyond the scope of this application.RésuméUn nouveau clou (Sirus) a été utilisé pour les fractures proximales de l’humérus. Ce travail fait le point sur les 36 premiers patients traités de cette façon. Le clou est verrouillé par trois vis dans trois directions différentes. 36 fractures ont été traitées de la sorte qu’il s’agisse de fracture de type 2 ou de fracture à 2 ou 3 fragments selon la description de Neer (J Bone Joint Surg 52:1077–1089). Le devenir de ces patients a été évalué selon le score de Constant. Sur les 36 patients évalués, 23 présentaient une fracture à 2 fragments et 13 à 3 fragments. L’âge moyen à l’intervention était de 71.2 ans (30 à 93). Ce traitement a permis d’obtenir également 75% de bons et très bons résultats. Le devenir a été satisfaisant dans 13.8% des cas. 25 fractures ont été traitées à foyers fermés. Le temps opératoire moyen a été de 41 minutes (de 19 à 106) et le temps d’utilisation de l’amplificateur de brillance de 0.6 minute (de 0.4 à 2.6). Un débricolage de la fracture est survenu dans deux cas. Après 12.1 mois d’évolution le score de Constant était en moyenne de 79.2 (de 46 à 100). Cette première expérience clinique montre que le taux de complications était relativement faible avec le traitement de ces fractures par le clou Sirus. Le devenir fonctionnel de ces patients reste bon ou très bon. Les fractures plus importantes de la grosse tubérosité ou les fractures à 4 fragments restent actuellement un sujet à l’étude.

Routine skeleton radiography using a flat-panel detector: image quality and clinical acceptance at 50% dose reduction.

Völk M, Paetzel C, Angele P, et al. Routine skeleton radiography using a flat-panel detector: image quality and clinical acceptance at 50% dose reduction. Invest Radiol 2003;38:230–235. Rationale and Objectives.The purpose of this study was to evaluate image quality and clinical acceptance of a large-area, flat-panel X-ray detector for routine skeleton examinations at 50% dose reduction. Methods.A total of 153 examinations (307 images) of 100 consecutive patients were evaluated. The cesium iodide-amorphous silicon active-matrix imager had a panel size of 43 × 43 cm, a matrix of 3000 × 3000, and a pixel pitch of 143 &mgr;m. All images were obtained with a kilovoltage setting identical to conventional radiographies of speed class 400. The amperage values were reduced by 50% compared with standard dose. Images were presented to 3 radiologists, who subjectively rated image quality on a 4-point scale according to 5 criteria (bone cortex, bone trabecula, soft tissue, overall contrast, and overall impression). Three trauma surgeons rated the clinical acceptance on a 4-point scale. Clinical acceptance was defined as directly derived consequences or therapy based on the presented image quality. For both evaluations, 1 represented excellent, 2 represented good, 3 represented moderate, and 4 represented nondiagnostic image quality/clinical acceptance. Intermediate scores at 0.5 intervals were allowed. Results.The mean values for all 5 image quality criteria were rated good or excellent (≤2). A total of 4.2% (13 of 307) of the images were rated 2.5 to 3.5 concerning the overall impression. None of the imaging features was ranked more than 3.5 by any radiologist. The mean value of the clinical acceptance was between good and excellent (1.47). A total of 98.7% (151 of 153) of the examinations were rated ≤2.5; 1.3% (2 of 153) of examinations were of moderate clinical acceptance (≤3.5). None of the examinations was of nondiagnostic image quality or clinical acceptance (>3.5); therefore, no study had to be repeated. Conclusion.Routine skeleton images with 50% dose reduction yield good image quality and good clinical acceptance. In cases with abundant soft tissue, less dose reduction or standard dose is required.

The impact of hypoxia on mesenchymal progenitor cells of human skeletal tissue in the pathogenesis of heterotopic ossification

PurposeMesenchymal progenitor cells (MPCs) are capable of differentiating into osteo/chondrogenic cells to contribute substantially to heterotopic ossification (HO). This study aimed to examine the impact of hypoxia on MPCs in the aetiology of HO.MethodsMPCs from human normal and HO skeletal tissue were cultivated under normoxia and hypoxia. Gene expression of factors which have a key role in HO aetiology (BMPs, COX-1 and COX-2, etc.) were examined by real-time PCR. Tissue of both groups was analysed by immunohistochemistry.ResultsUnder hypoxia, COX-1, -2 and SOX-9 gene expression was elevated in HO MPCs, whereas in normal muscle tissue only COX-2 was upregulated. MPCs from HO had a significantly elevated gene expression of BMP-4 and decreased expression of BMP-1 and HIF-1 under hypoxia compared to normal MPCs. Immunohistochemistry detected no significant differences between normal and HO tissue.ConclusionsHypoxia causes an enhanced gene expression of factors, which have a key role in HO pathophysiology. A better understanding of this entity will possibly allow reducing HO rates in orthopaedic and trauma surgery.

Peri-implant femoral fractures: The risk is more than three times higher within PFN compared with DHS

INTRODUCTION Information is lacking regarding incidence rates, treatment regimens, and outcomes concerning peri-implant femoral fractures (PIF). Therefore, we performed a retrospective study to provide scientific data concerning incidence and outcome of PIF following osteosynthesis of proximal femoral fractures (PFF). MATERIAL AND METHODS We retrospectively included all patients who received osteosynthesis for PFF between 2006 and 2015 and in whom PIF was confirmed postoperatively. All available patients with PIF were contacted minimum one year post-surgery. RESULTS A total of 1314 osteosynthesis procedures were performed, of which 705 were proximal femoral nails (PFNs), 597 were dynamic hip screws (DHSs), and 12 were screws appliances only. During the same period, 18 PIFs (1.4%) were reported. However, PIF was 3.7 times higher within PFN when compared to DHS (15/705:2.1% versus 3/597:0.5%; odds ratio: 3.7). The following analysis also included 8 patients with PIF who were referred from other hospitals, resulting in a total of 26 patients. Mean patient age was 84.8 years (range, 57-95), with a predominance in female (23×) and in the left femur (19×). PIF occurred after an average of 23.6 months (range, 1-81) post-surgery. The fractures, most of which were spiral-shaped, were most commonly treated with locking plate osteosynthesis. The surgical revision rate was 7.7%, and the one-year mortality was 23.1%. At an average of 43.0 months (range, 12-100) post-surgery, it was possible to contact 18/26 patients (69.2%), and their mean Parker Mobility Score was 5.2 points (range 2-9). CONCLUSIONS Peri-implant femoral fracture is a rare incident within the old age traumatology of PFF. However, based on our small number of cases, it occurred within PFN much more frequently compared with DHS. Locking plate osteosynthesis has been shown to be effective and reliable. Surgical revision and mortality rates do not appear to be increased when compared to those with the initial treatment of proximal femoral fractures.