[Special reduction instruments]. / Spezielle Repositionsinstrumente.

Special and specialized instruments help perform reduction more effectively and in a tissue-preserving manner. In addition to other articles, the application and advantages of the following instruments are presented: colinear reduction forceps, cerclage, cerclage passer, distal radius reduction clamp, modular external fixator, extension table, distraction frame, joystick, manipulators, distractor and assistance of reduction with elastic nails.

[Surgical Treatment of Acetabulum Fractures with a New Acetabulum Butterfly Plate]. / Operative Versorgung von Azetabulumfrakturen mit der neuen Azetabulumflügelplatte.

Introduction: There have been significant increases in the number of acetabular fractures in elderly patients with primarily ventral pathology and medial protrusion of the femoral head. We have developed the "acetabulum wing plate", which is designed to facilitate repositioning, with its anatomically precontoured structure, and which offers full support of the quadrilateral surface, thus counteracting the force of the femoral head pushing inwards. Conventional plate osteosynthesis only provides insufficient support to the medial surface. After a successful series of biomechanical tests, we now report a clinical case series. Material and Methods: Between April 2012 and August 2013, a total of twelve patients underwent plate osteosynthesis using the precontoured plate described above. The patients (ten male, two female) were aged between 45 and 87 years, the average age being 62.5 years. We were able to perform all osteosynthesis with the modified Stoppa approach, in combination with the first window of the ilioinguinal approach (according to Letournel). In most patients, the plate was applied without complications, In some patients, it even supported repositioning. In six patients, the fractures were of the anterior collum and six fractures were fractures of both colla. The mean time span of follow-up was 13.1 months, the minimum being 4.5 and the maximum 23 months. Results: In most patients, the intra- and postoperative computed tomographic scans showed anatomically correct placement of the plate, thus confirming the correct repositioning of the bone. Routine follow-ups are part of the hospital's postsurgical care system for acetabular fractures; these revealed no secondary dislocation or loosening of the plate. The radiological examination showed consolidation of the fractures after a mean period of twelve weeks. A full year after the initial procedure, no implant-specific complications were observed. Revision surgery was necessary in one patient due to bleeding five days after surgery. In another patient, necrosis of the femoral head necessitated total hip replacement ten weeks after the first surgical intervention. In summary, the concept of the plate proved to be successful in its first case series. Summary: In spite of increasing surgical expertise and the refinements of standard approaches, there is a recognisable shift in acetabular fractures from mainly posterior fracture patterns to fractures of the anterior column. The new acetabulum wing plate takes these factors into account and is an implant designed to address the anterior aspects of the acetabulum. The outcome of the first application is promising and the acetabulum wing plate produces satisfactory results in our patients.

[Augmentation with PMMA cement]. / Augmentation mit PMMA-Zement.

Cements based on polymethyl methacrylate (PMMA) can be used without any problem in a variety of clinical augmentations. Cement-related complications in surgical procedures involving PMMA cements, such as embolism, thermal necrosis, toxicity and hypersensitivity, are often due to other causes. Knowledge about the properties of the cement helps the user to safely employ PMMA cements in augmentations. High radio-opacity is required in vertebral body augmentations and this is provided in particular by zirconium dioxide. In vertebral body augmentations, a low benzoyl peroxide (BPO) content can considerably prolong the liquid dough phase. In augmentations with cement fillings in the region of a tumor, a high BPO content can specifically increase the peak temperature of the PMMA cement. In osteosynthetic augmentations with PMMA, necrosis is rare because heat development in the presence of metallic implants is low due to heat conduction via the implant. Larger cement fillings where there is no heat conduction via metal implants can exhibit substantially higher peak temperatures. The flow properties of PMMA cements are of particular importance for the user to allow optimum handling of PMMA cements. In patients with hypersensitivity to antibiotics, there is no need to avoid the use of PMMA as there are sufficient PMMA-based alternatives. The PMMA cements are local drug delivery systems and antibiotics, antiseptics, antimycotics and also cytostatics can be mixed with the cement. Attention must be paid to antagonistic and synergistic effects.

[Femoral nailing using a helical nail shape (LFN(®))]. / Marknagelung des Femurs mit einem helikalen Implantat (LFN(®)).

OBJECTIVE: Antegrade femoral nailing through a greater trochanteric entry portal avoids damage to the proximal external rotators and to the ramus profundus of the medial femoral circumflex artery, furthermore eases insertion in adipose subjects. However a helical nail shape is necessary for this pathway because bending in two perpendicular planes has to be passed by the nail. INDICATIONS: All femoral shaft fractures suitable for antegrade nailing (type 32-A/B/C). Additional femoral neck fractures (type 31-B) by using proximal Recon-interlocking screws. CONTRAINDICATIONS: The common contraindications for femoral nailing. In certain subtrochanteric fractures (Type 32-A/B) the proximal femoral nail may be favorable. SURGICAL TECHNIQUE: General or spinal anesthesia. Supine position with flexion/abduction of the contralateral leg in order to facilitate fluoroscopy of the proximal femur in a true lateral view. Closed reduction of length and axis. Measurement of length and diameter of the nail using a radiolucent ruler. Dorsolateral approach to the greater trochanter. Insertion of the guide wire 10 mm lateral to the trochanteric tip (anteroposterior view) and in the middle third of the trochanter (lateral view). Reaming of the insertion point using a flexible reamer. If reaming of the entire medullary canal is desired, this should be done using a long intramedullary guide wire in combination with a long flexible reamer. Insertion of the nail starts in an anterior position and ends in a lateral position of the insertion instrument, so a 90° external rotation of the nail occurs during insertion. Proximal interlocking is performed using the guide of the insertion instrument. Check interfragmentary rotation. Distal interlocking using a radiolucent drill device. POSTOPERATIVE MANAGEMENT: Depends on the fracture shape: stable interfragmentary support may allow early full weight bearing. Otherwise, reduced weight bearing is recommended for at least 6 weeks. RESULTS: In a prospective mulicentric study, 227 helical femoral nails were used for antegrade femoral nailing. Follow-up after 12 month was available in 74 %. Surgeons' rating for ease of identifying entry site was excellent or good in 89 %. Functional and radiological results after 12 months do not prove significant benefits over conventional antegrade femoral nails.

[Dynamic locking screw 5.0--first clinical experience]. / Dynamic Locking Screw 5.0--erste klinische Anwendung.

The principle of "biological" plate osteosynthesis describes the optimum interaction between mechanics and biology with the aim to achieve an uneventful consolidation of the fracture by secondary bone healing. The preservation of soft tissue and blood supply are central points in this context. Empirical values show that a too rigid internal fixation can suppress callus formation. The dynamic locking screw - DLS - allows for a decrease of the rigidity of a plate osteosynthesis. The fracture motion is positively affected. The advantages of the angular stability are not affected. In the Trauma Centre Tuebingen 35 patients were treated with the DLS5.0 in the time between November 2011 and October 2012. These first clinical cases with the use of the large fragment DLS showed good results. Handling the DLS5.0 is comparable to the conventional locking screw - LS5.0. Complications were not caused by the DLS and their application.

[Experiences with a helical femoral nail (LFN®). A multicenter study]. / Erfahrungen mit einem helikalen Femurmarknagel (LFN®). Eine multizentrische Studie.

INTRODUCTION: Antegrade intramedullary nailing is the method of choice in most femoral shaft fractures. The trochanteric entry portal of classic femoral nails is in close proximity to the piriformis tendon, the gluteus minimus tendon, the obturator tendons, and the medial femoral circumflex artery. Nail insertion lateral to the tip of the greater trochanter may be more favorable but needs the use of a helical implant. MATERIAL AND METHODS: Measurement of the reamer pathway through an entry point lateral to the superior trochanteric border was performed with a three-dimensional motion tracking sensor in human cadaveric femurs. These results provided a scientific rationale for the design of a helical femoral nail (LFN®). In a prospective multicenter study a total of 227 femoral shaft fractures were treated by nailing with the LFN. Patients were followed at 3 months (n=193) and 12 months (n=167). RESULTS: The ease of defining the entry point and inserting the nail was rated as"very good and good" by 90% of the surgeons. Intraoperative technical complications included incomplete reduction (14%), additional iatrogenic fractures (6%), and difficulties in interlocking (3.5%). At the 1-year follow-up, delayed unions were seen in 10%, secondary loss of reduction in 3%, and deep infection in 1.8% of the patients. Angular malalignment of more than 5° was seen in 5%, mostly in valgus. A normal walking capacity was seen in 68% and normal active hip flexion in 45%. CONCLUSION: The results obtained in this study during 1 year do not provide evidence for an advantage of the LFN over conventional antegrade femoral nails.