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P Keppler

Publications and source records attributed to P Keppler.

At least 19 recordsLinked to original sources
PubMed2005

[Post-traumatic torsional differences and functional tests following antegrade or retrograde intramedullary nailing of the distal femoral diaphysis].

Previous studies have compared the functional outcome and torsional differences following closed intramedullary nailing of femoral fractures. Rotational deformity following intramedullary nailing may cause symptoms and require surgical correction by osteotomy. Until now studies were designed to evaluate the correct torsional differences by examining every patient following antegrade or retrograde femoral nailing. The series included 13 women and 28 men, average age 44.5 years, who suffered a fracture of the distal femoral diaphysis. Postoperatively we established the diagnosis by three-dimensional determination of the torsion and length of the lower extremities by ultrasound measurement. Furthermore, we performed the clinical examination according to the Tegner and Lysholm score and the Merle d'Aubigne score. There were no significant differences in torsional deformity and length found. The functional outcome showed no significant differences between the two groups. The functional examination exhibited a reduction of flexion in knee motion in the retrograde group. In the antegrade group the motion of the hip was decreased. A correlation between the functional outcome and the torsional deformity was not found. The possible advantage of positioning by using the retrograde femoral nail was not verified.

Adult↗
PubMed2005

[Clinical results with A new retrograde femoral nail with a radiographical-free proximal locking device. A prospective study with 50 fractures].

INTRODUCTION: Conventional retrograde nailing of the femur causes two important disadvantages: the proximal locking of the nail is difficult because of the anatomic conditions and a chondral defect was left into the knee. MATERIAL AND METHODS: After the retrograde implantation the new nail was lead through the greater trochanter. An additional proximal aiming device for proximal interlocking can be fixed. The entrance portal will be sealed by an osteochondral cylinder. 50 cases of femur fractures were selected for the prospective study. We recorded all intraoperative complications and technical difficulties. The cases were followed up for 52 weeks, both clinical and radiology examinations were performed. RESULTS: The mean follow up was 15.5+/-5 months. All fractures were healed. Knee movement was 125+/-14 degrees. The Leung Score was 84+/-12.6 points; HSS Score was 90+/-9 points. In two cases wound infections were developed. Mal-union was observed in three cases, in two cases nail brake down. CONCLUSIONS: The new retrograde interlocking nail could be used to manage femur fractures successfully. Two aiming devices enable a easy interlocking. Replacement of the osteochondral cylinder into the entry portal reduces cartilage damage.

Adolescent↗
PubMed2005

[Computer-assisted knee surgery, what can we expect?].

Navigation systems for operative assistance in knee joint surgery have been established in the last 5 years. Among the large number of variable systems, the image-free kinematic systems have won widespread acceptance. The C-arm based systems are not superior to the image-free systems. The CT-based systems are advantageous in completely destroyed joints (with marked joint erosion) or advanced congenital or traumatic deformities. The intraoperatively-performed Iso-C (3D) technique presents data sets in CT-quality, but because of its small data volume currently is limited to the reconstruction of articular surfaces following fractures. The use of image-free navigation in resurfacing knee arthroplasty is in the meantime beyond controversy whereby deviations in the mechanical axis from normal values can be significantly reduced. For high tibial osteotomies navigation modules will be soon available for marketing. However, with these modules, intraoperative imaging is indispensable, but it will be image-free in the future. The early clinical results are promising. Cruciate ligament navigation is not yet a clinical standard be-cause of the considerable associated time expenditure. The appropriate modules are still under development.

Adult↗
PubMed2004

[Total knee arthroplasty--navigation as the standard].

Today the most common application in the field of computer-assisted surgery is navigated total knee arthroplasty. During the last 5 years the imageless kinematic navigation systems have gained wide acceptance. As several prospective randomized studies could show, the standard deviation of the mechanical axis is reduced significantly by these techniques. However, the direction of the mechanical axis is only one factor which influences the long-term results of total knee arthroplasty. Further important factors are ligament balancing and position of the femoral and tibial components in all three planes. Up to now no studies have been able to show a significantly better functional result, a more rapid recovery, or a decreased complication rate. Drawbacks of the navigation systems are the additional costs and the additional operation time between 15 and 20 min. Therefore, navigated total knee arthroplasty is not yet a standard procedure, but this technique is well on the way to becoming the gold standard in the future.

Algorithms↗
PubMed2002

[Osteotomies in malalignments of the lower extremities].

The surgical correction of malalignments of the lower extremities is a very demanding procedure. It requires extensive knowledge of: (1) fundamental lower extremity biomechanics, (2) various diagnostic modalities, and (3) methodology for multidimensional preoperative planning. Despite advanced techniques in diagnostics and surgery, the history of the patient and a physical examination are still the first steps in the diagnostic chain. The knowledge of the method-dependent normal values, their physiological range and intra-individual differences are a prerequisite. In posttraumatic deformities, the healthy leg is a good reference for the patient's geometric orientation. As a rule, values differing by three times the standard deviation or more are good indications for an operation. These are 15 and 12 mm for the upper and lower leg, 18 and 15 mm for the whole leg and only 3 degrees mm for the mechanical leg axis measured using computer tomography and long standing x-rays, respectively. The indication for surgical correction is not only based on geometric data. The patient's functional needs, symptoms, complaints and compensation possibilities must also be taken into account. The lower extremities have to be assessed in a psychosocial context. Among the huge number of possible surgical techniques, the procedure best suited for the patient has to be selected. This requires extensive knowledge and advanced technical skills from the treating orthopaedic surgeon. In supracondylar or high tibial osteotomies for the treatment of medial arthritis of the knee joint, the patient should be informed of the long term prognosis and endoprosthetic alternatives. Today, percutaneous epiphysiodesis is a very reliable and minimally invasive surgical technique for correcting the length and axis of the lower extremity in children between 10 and 14 years. With well planned epiphysiodesis procedures, it is often possible to avoid complex osteotomies in younger patients.

Adolescent↗
PubMed2002

[Ultrasound hard tissue detection for registration in orthopedics and traumatology].

The application of x-ray diagnostics for intraoperative navigation and for registration of hard tissue structures is restrained due to high radiation loads and the not given real time ability. Previous approaches with conventional ultrasonic imaging are only interactively applicable due to the high information content of soft tissue optimised B-mode-images. A pure image processing does not allow an automatic identification of individual structures, so that this must be done by the physician. To decrease the high expense of time, this report presents a concept for an adapted chain of rf-signal processing as well as an ultrasonic system for the contrast-enhanced representation of tissue borders. The system permits an exact measurement of the body geometry, which is demonstrated by determining the position of the pelvis entry plane.

Algorithms↗
PubMed2002

Operation planning of correction osteotomies in 3D.

This paper discusses an operation planning system for correction osteotomies. It is based on 3D data obtained from CT/MR of the bone and it allows to perform a 3D planning. The physician can individually determine anatomical landmarks for measuring geometric parameters of the bone like length, angle and torsion angle. In a virtual scene he or she can set a single cut or can remove/insert a wedge, dissecting the bones. The bone parts can be rearranged in 3D space. Optimization routines allow that the physician only defines the position of the cut, the orientation of the cut plane, the rearrangement of the bone and the optimization for the maximal overlap of the cortical bone can be processed automatically. The system is currently in use at the Trauma department at the University of Ulm. A case study shows the results by applying this system.

Bone Malalignment↗
PubMed2001

[Corrective osteotomies of the distal femur with retrograde intramedullary nail].

Deformities of the distal femur are usually corrected by supracondylar osteotomy. In the "classical" procedure the bone cut is performed with an oscillating saw, and internally fixed using a plate. This technique is hampered first by an invasive approach and second by limited corrective options in case of complex deformities. A supracondylar bone cut by focal dome osteotomy or drill osteoclasis in combination with internal fixation by retrograde intramedullary nailing (RN) might be a promising alternative procedure. 12 patients with multidimensional post-traumatic deformities of the distal femur were prospectively enrolled in a study to investigate this new minimal-invasive technique. In all patients a meticulous analysis of leg geometry was done pre- and postoperatively. Details of operative planning, osteotomy and fixation procedure are given as well as the postoperative treatment. 7 corrective osteotomies were one-step procedures, in 5 patients additional lengthening over the RN was performed using unilateral external fixation. The mean follow-up was 15 (range 7-27) months. All of the osteotomies healed in a normal expected time frame. All patients had important functional benefits. In 11 patients the goal of deformity correction was achieved. In one patient the correction in the frontal plane remained insufficient. 6 months after the completion of femoral lengthening osteomyelitis developed in one patient, probably due to a pin-track infection. The infection subsided after early removal of the RN. No further complications were observed. The presented technique is demanding concerning pre-operative planning and surgical realization but it offers a minimal-invasive and promising approach for the correction of multidimensional femoral deformities.

Adult↗
PubMed2001

Computer assisted treatment of pelvis fractures.

The presented approach is the realization of a minimal invasive treatment of pelvis fractures using the computer aided surgery (CAS). Main problem of tracking of major bone fragments after reposition is solved by implementing of 3D ultrasound to obtain intraoperative bone surfaces. Preoperative and intraoperative data sets are matched. Major fragments are tracked. The real time navigation is possible.

Feasibility Studies↗
PubMed2001

Computer simulation of osteotomy correction.

This paper describes a novel approach to correct osteotomy deformities of long bones using virtual reality and image processing techniques on personal computers. The discussed method allows to simulate osteotomy corrections by implementing a single cut and a rearrangement of the dissected bone parts. It allows the surgeon to directly control the pre-operative situation and the post-operative result of the simulation by comparing bone-length, angles, and torsion of the bone. In addition, he or she obtains the coordinates and angles of the planned cut relative to anatomical landmarks.

Bone Malalignment↗
PubMed2000

The effectiveness of ADCON-T/N, a new anti-adhesion barrier gel, in fresh divisions of the flexor tendons in Zone II.

In a prospective randomized clinical trial, ADCON-T/N was investigated with regard to its effectiveness in fresh traumatic injuries of the flexor tendons in Zone II of the hand. Thirty patients participated in the trial. Following a standardized technique of tendon repair, the total active motion (TAM) and total extension lag (TEL) were determined after 12 weeks and evaluated according to the Buck-Gramcko score. Excellent results were achieved in 15 out of 16 patients in the ADCON-T/N group and 12 out of 14 in the control group. However, no statistically significant difference was found between the mean TAM and TEL in the two groups.

Administration, Topical↗