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C Krettek

Publications and source records attributed to C Krettek.

At least 127 records · Page 7Linked to original sources

[Development of a standardized instrument for quantitative and reproducible rehabilitation data assessment after polytrauma (HASPOC)].

INTRODUCTION: Previous scoring systems for measurement of the quality of outcome are based on scores regarding injuries to individual body regions. Known scores which describe several organ regions are of no importance for trauma patients. Therefore a new rehabilitation outcome evaluation score was developed at our hospital. METHODS: Based on a prospective reinvestigation, a score system was developed that allows a quantitative appraisal of the subjective and objective outcome. A complete physical examination was performed, including ROM, neurologic examination and strength analysis. Part I (113 questions) is to be filled out by the patient; part II (191 questions) focusses on different body regions, physical examination and functional scoring. Included are the MFA, FIM, GCO and Frankel score. A final score (HASPOC) was developed to give a quantitative result of the outcome. RESULTS: The new score has a range from 5 to 411 points. One hundred and fifty patients were re-examined. The mean follow-up time was 2.2 +/- 0.1 years. The SF 12 indicated an outcome more than satisfactory in 63% of cases. The MFA demonstrated moderate or severe restrictions in 41%, in the case of injuries of the lower extremity in 52% of patients. The HASPOC indicated a mean of 44.5 points. CONCLUSION: This paper describes the development, structure, and the quantitative outcome of rehabilitation in polytrauma patients. This standardized rehabilitation instrument deals with a very heterogeneous patient population and shows the rehabilitation deficits accurately. Implemented recognized evaluations allow comparison of these results with those of other scoring systems.

Data Collection↗

[Minimally invasive screw fixation of the intracapsular femoral neck fracture in elderly patients].

INTRODUCTION: Increasing life expectancy is associated with an increase of geriatric fractures such as intracapsular femoral neck fractures. Their treatment by arthroplasty imposes a significant burden on our health care system. METHODS: In an open clinical study we investigated the complication rate of a less expensive and less invasive, femoral head saving operative procedure. Between June 1997 and June 2000, 205 intracapsular femoral neck fractures of elderly patients (mean age 78.1 +/- 11.8 years) were fixed with cannulated screws. RESULTS: Seventy-seven percent were displaced fractures and 15.6% were impacted Garden I fractures. Reoperation after internal fixation occurred in 38 patients. The most frequent cause of reoperation was secondary arthroplasty due to redisplacement (14x), femoral head necrosis (10x) and non-union (7x). Implant removal (4x), wound hematoma (1x) and femoral head penetration by screws (2x) were other causes for reoperation. CONCLUSION: Less invasive cannulated screw fixation of intracapsular femoral neck fractures should be considered as a treatment option, because it is a smaller and less expensive operation than prosthetic replacement. Adequate reduction and screw placement, however, are a prerequisite for successful outcome.

Aged↗

[Osteosynthesis of fractures of the head of the tibia in advanced age. A matched-pair analysis].

In a retrospective study we analyzed 183 patients with tibial head fractures. 15 patients were older than 60 years at the time of accident, with a mean age of 69 (62-81) years. All patients had sustained an isolated tibial plateau fracture with a split-impression fracture in 10 patients, an impression fracture in 2 patients and a bicondylar fracture in 3 patients. The mean time to follow-up was 5.1 years. In a matched-pair-analysis this group was compared to a group of young patients with a mean age of 43 years (26-56) and identical lesions and surgical procedures. The mean time to follow-up in this group was 4.2 years. We observed that fractures at higher age resulted mostly from trivial accidents. Except from a prolonged inpatient time the initial course was comparable. In a 66 year-old woman early implant removal was necessary because of infection. Despite identical surgical treatment we observed a loss of reduction with incongruency of the plateau and deviation of the axis. Correspondingly older patients displayed a statistically significant threefold increase of osteoarthritis compared to younger patients. However, there was no clinical correlation using the Rasmussen, OAK and Lysholm score. Both groups displayed no statistical significant differences for the parameters function, stability and pain. According to the old age the only significant difference was a reduction of the Tegner score. Reduction and internal fixation of tibial plateau fractures in an elderly population displayed mostly a satisfactory clinical result within this 5-year period. The problem of loss of reduction and rapid osteoarthritis remains to be evaluated in a larger group over a longer period of time.

Aged↗

[Multiple trauma with craniocerebral trauma. Early definitive surgical management of long bone fractures?].

Head injuries are found in 17.6% of all trauma in-patients and are the most common cause of death after injury (26.6%) in Germany. Main factors for the initial and follow up assessment are the Glasgow Coma Scale (GCS) and pupil reaction. These are of a very predictive value for the outcome and are essential for the emergency crew to choose the adequat trauma hospital. Secondary transport to a higher level trauma center is affected by additional risk factors and a delay in diagnosis resp. treatment. This will increase mortality and must be strictly avoided. Sufficient oxygenation and circulation prevent the patient from secondary brain damage. A low GCS (< or = 8 p.) or specific additional injuries are an indication for immediate intubation. The outcome in patients with a systolic blood pressure below 90 mmHg on arrival is worse: The longer the time of correction the lower the rate of survival. After resuscitation early fracture treatment depends on hemoglobin concentration, hemostasis, oxygenation, body temperature, injury pattern and on the initial cranial CT scan. Cerebral swelling, seen or expected, is a contraindication for definitive fracture stabilization. After resuscitation reassessment should be done including a second CT scan. Cerebral monitoring is best performed by continuous measuring of the intracranial and the arterial pressure. Their difference determines the cerebral perfusion pressure which should be 60 mmHg at least. Intracranial pressure rates below 20 mmHg are favourable. Optimal management within the first days is essential for good outcome.

Adolescent↗

[Knee joint prosthesis implantation after fractures of the head of the tibia. Intermediate term results of a cohort analysis].

A significant number of patients with operated tibial plateau fractures develop osteoarthritis and require total knee arthroplasty. In cases of primary osteoarthritis the results are generally good. However, it is not known whether patients with post-traumatic osteoarthritis obtain comparably favorable results. In a retrospective study we analyzed 72 patients who had undergone a self-aligning (SAL) total knee arthroplasty. Ten patients received arthroplasty due to sequelae of a tibial head fracture (group I). The median time to follow-up in this group was 30 months. Clinical and radiological evaluation was based on the Knee Society Clinical Rating System. The score comprises pain, range of motion, stability, and function. We defined the axis and possible loosening by radiological examination. For comparative descriptive statistics, a cohort of patients was chosen who had received an arthroplasty because of primary gonarthrosis (group II, 76 arthroplasties in 62 patients). The median time to follow-up in this group was 46.5 months. Three patients in group I underwent revision surgery, four patients displayed severe functional deficits and pain, and one patient had a varus deformity with good clinical function. This corresponded to an early complication rate of 27% and a late complication rate of 36%; a relevant instability or loosening of the components did not occur in this group. In group II the incidence of early complications was 10%. The patients in group I reached a mean value of 153 points using the rating system vs 167 points in group II. Analyzing the clinical parameters of the score, we found that patients in group I experienced significantly more pain, thereby affecting functions of daily living, such as walking and climbing stairs. Because of the small number of patients in group I, conclusions can only be drawn to a limited extent. However, we saw that these patients displayed a higher incidence of complications and performed less well. This has to be taken into consideration and discussed prior to surgery.

Activities of Daily Living↗

[Electric accident. New aspects regarding pathophysiology and treatment].

The complex pathophysiology of electrical injury is caused by several mechanisms which are superimposed and cumulative in action. Existing empirical guidelines are only partially compatible with the results of recent studies. The significance of the joule effect, theories about progressive tissue necrosis, and the traditional surgical approach should be reviewed in view of electroporation and anatomical arrangements. The quality of long-term treatment results and the consistently high rate of amputations have prompted the development of alternative surgical options.

Burns, Electric↗

[Bone segment transport of the femur. Biomechanical value of an unreamed titanium intramedullary nail with reference to stiffness of external distraction systems].

The influence of an unreamed femur nail on axial and torque stiffness of nine different external fixator devices was investigated in a biomechanical study. With a newly developed femur bone model simulating segmental transport, 582 biomechanical tests were performed. The additional use of an unreamed femur nail (UFN) increased axial stiffness of the external fixator devices up to 8108% (average 1673.8-2631.8%) and increased torque stiffness up to 86% (average 47%). The best results could be achieved when combining a small-diameter UFN (9 x 360 mm, Synthes Co.) and external fixator devices with high torque and comparatively little axial stiffness. The use of stainless steel half-pins instead of titanium half-pins improved torque stiffness significantly. Concerning the biomechanical demands made on external fixator devices used for femoral segmental transport, the Hexfix fixator with steel bar and steel half-pins combined with an UFN achieved the best results.

Biomechanical Phenomena↗

Rupture of the patellar tendon: a review of 68 cases and a retrospective study of 29 ruptures comparing two methods of augmentation.

Rupture of the patellar tendon is a rare injury requiring acute repair to reestablish knee extensor continuity and to allow early motion. Different pathomechanisms have been postulated, and multiple techniques for repair have been described in the literature. Firstly, the current study reviews the epidemiology, pathomechanism, and risk factors. Secondly, we compare the outcome of two augmentation techniques after end-to-end sutures: reinforcement with either a wire cerclage or a PDS cord. In the first part of the study, the medical records of 66 patients with 68 ruptures were reviewed. For the second part, 33 patients were included who had no prior injury to the extensor mechanism of the knee and had suffered an indirect, low-velocity injury followed by immediate repair. Twenty-seven patients with 29 ruptures of the patellar tendon returned for follow-up. Follow-up averaged 8.1 years (range 1-16 years). In the follow-up group, 22 ruptures had augmentation with a wire cerclage (group A), and 7 ruptures had augmentation with a 2-mm PDS cord (group B). Follow-up evaluation consisted of a subjective questionnaire, a physical and radiographic examination, the Hospital for Special Surgery Knee Score, and the Insall-Salvati ratio. Nineteen patients underwent Cybex isokinetic strength testing of the quadriceps. Indirect, low-velocity injuries occurred most often in the 30-40 year age group, whereas complex knee traumas or knee luxations were more evenly distributed. In 10 of 46 patients with an indirect, low-velocity injury, there was a history of prior injury and illness to the extensor mechanism of the knee, compared with 1 of 22 patients with a high-velocity complex knee trauma. In the follow-up group, no patient sustained a rerupture. Two of 22 patients had an extension lag in group A compared with no extension lag in group B. Average flexion in group A was 130 degrees (SD 29 degrees) compared with 137 degrees (SD 12 degrees ) in group B. The average Hospital for Special Surgery Knee Score was 92 (SD 17) in group A and 96 (SD 12) in group B. Three patients were dissatisfied. All had radiographic signs of retropatellar osteoarthritis. In contrast, 9 of 26 patients who were satisfied with their result had radiographic signs of retropatellar osteoarthritis. A postoperative difference in the Insall-Salvati ratio did not correlate with the development of osteoarthritis. Both augmentation techniques are reliable and demostrate good intermediate to long-term results. The outcome did not show significant differences. To avoid reoperation for removal of the cerclage wire, a PDS cord can be used. The infection rate seems to be higher in the PDS group. A larger prospective study group is necessary to determine whether this phenomenon can be reproduced.

Female↗

Hannover Fracture Scale '98--re-evaluation and new perspectives of an established extremity salvage score.

OBJECTIVE: as the treatment of open fractures has improved over the years, the prognosis of open fractures has also changed. Thus, a re-evaluation of the Hannover Fracture Score (HFS), first introduced in 1983, has become necessary. DESIGN: retrospectively all parameters of the HFS were evaluated in 182 open fractures of the upper and lower extremity treated in our institution between June 1994 and 1996. Statistical means included multivariant analysis, ROC analysis, calculation of sensitivity, specificity and accuracy. Finally the HFS 98 was established, which is characterised by eight domains with a total score range from 0 to 22 points and a cut off point (amputation recommended) at a score > or =11. This score was then prospectively applied on another 87 open long bone fractures, treated during July 1996 and December 1997. RESULTS: this validation of the HFS '98 revealed a sensitivity of 0.82 and a specificity of 0.99. In comparison the NISSSA and the MESS presented a lower sensitivity and same specificity based on the same study group. CONCLUSION: in conclusion the HFS '98 has become a reliable extremity salvage score with a fairly high positive predictive value of 0.99, which is applicable for all the open long bone fractures regardless of their location.

Adult↗

A minimally invasive medial approach for proximal tibial fractures.

Numerous techniques have been described for MIPPO (minimally invasive percutaneous plate osteosynthesis) for metaphyseal or combined metaphyseal-articular fractures of the proximal tibia. Surgical management is often complicated by the initial soft tissue damage, malalignment, remaining instability, or infection. In this prospective cohort study, we describe the diagnostic procedures vital for preoperative planning. These include plain radiographs and CT scans in case of articular fracture components. The techniques for temporary stabilization and definitive fracture care using 4.5 mm DCP, LC-DCP, and LISS (Less Invasive Stabilization System) by limited medial incisions are described in a stepwise protocol. From 1996 to 1998, six fractures in six patients were studied. According to the AO classification, there were four type 41 fractures and two type 42 fractures. One patient died of ARDS. All patients had an intact medial soft tissue coverage allowing a medial approach. One patient developed a compartment syndrome, which was addressed by lateral dermato-fasciotomy prior to osteosynthesis. A LISS was used in three patients. The only complication related to surgery was in a patient with a four-part fracture with lateral comminution and a dislocated postero-medial fragment, which was reduced and buttressed with a short posteromedial 3.5 mm small fragment plate. This patient developed a deep, intraarticular infection, which was successfully treated with revision surgery; the implants were left in situ. At her latest follow-up at 18 months, she had a range of motion of 0/10/110, was back at work, and able to participate in recreational sports. The average time to healing was between 12 and 20 weeks postoperatively. There was no delayed healing, pseudarthrosis, recurrent fracture or late infection. None of the cases needed bone grafting. At the most recent follow-up, all patients were bearing full weight without walking aids. All cases achieved a neutral alignment and satisfactory range of movement. Though further data are needed we have sound reason to propagate a single medial approach and minimally invasive osteosynthesis as a sufficient and subtle technique for stabilization of these complicated fractures.

Adult↗

Evolution of minimally invasive plate osteosynthesis (MIPO) in the femur.

Problems with conventional open reduction and internal plate fixation of distal femoral fractures are well established. These problems have been associated with extensile exposures of the fracture site. "Biological plating", like intramedullary nail fixation, of distal femoral fractures preserves the soft tissues about the fracture, and is associated with early fracture consolidation and low rates of infection. Anatomical restoration of the articular surface continues to be the main goal in the treatment of these fractures regardless of the stabilization technique. Submuscular plating techniques, which provide for closed reduction of the diaphyseal/metaphyseal component of the fracture, have improved significantly.

Bone Plates↗

Minimally invasive fracture stabilization of distal femoral fractures with the LISS: a prospective multicenter study. Results of a clinical study with special emphasis on difficult cases.

The LISS-DF (Less invasive stabilization system-distal femur) is a new type of implant system for the treatment of distal femoral fractures according to the principles of "Minimally Invasive Surgery". A plate, pre-contoured to the anatomy, is inserted through a minimally invasive incision into the epiperiosteal space by means of an aiming device after indirect, closed fracture reduction. The implant is stabilized by insertion of screws which lock into the plate holes and prevent tilting. This is performed with the aid of an aiming device and through stab incisions. It is not necessary for a large area to be exposed at the fracture site. As part of an AO prospective multicenter study, the new system was applied to 112 patients with 116 fractures. The time to follow-up was on average 13.7 months (minimum 7 months, maximum 33 months). Fractures treated were distal femoral shaft and supracondylar femoral fractures. Eight patients died during the study of causes unrelated to the implant. Of the remaining 104 patients with 107 fractures, 96 patients with 99 fractures were available for complete follow-up (93% follow-up rate). In 90% of all cases treated and followed up, the fracture had consolidated during the period of observation. Twenty-three revision operations were necessary in 21 patients. In two cases, implant failure occurred as the result of a pseudarthrosis. The complications can be attributed in nearly all cases to the severity of the trauma and/or a lack of experience when applying the new style implant to a wider range of indications. The results of the study show that with a sound knowledge of the operative technique and careful preoperative planning this system represents an excellent, safe procedure for the treatment of almost all distal femoral fracture types including periprosthetic fractures of the distal femur. There is generally no need for primary cancellous bone grafting.

Adolescent↗

Distal femoral fractures and LISS stabilization.

In recent years, the technique of surgical stabilization in the distal femur has changed. This change decreased the number of non unions and the need for bone grafting. Minimally invasive surgical techniques with a submuscular plate placement have replaced the emphasis on anatomical reduction in the shaft area. Reconstruction of complex articular injuries has been simplified by more direct visualization of the articular surface with the lateral peripatellar approach. Problems remaining are surgical technique and implant considerations. The Less Invasive Stabilization System (LISS) simplifies the surgical technique for percutaneous plate osteosynthesis. An insertion guide is used to insert monocortical, self-tapping screws through a stab incision. A thread in the plate provides the angular stability for the anchoring of these screws. In extra-articular fractures and simple intra-articular fractures, the distal femoral nail permits intramedullary stabilization. A spiral blade improves fixation of the distal femoral condylar block. Despite the enhanced surgical technique and implant possibilities, a great number of patients show a functional deficiency. These are particularly patients with complex intra-articular fractures. The 'fatigue failure' of the osteoporotic implant-bone construct is a problem in elderly patients. The LISS represents a good option to avoid the addition of bone cement to an osteosynthesis.

Adult↗

Novel computer-assisted fluoroscopy system for intraoperative guidance: feasibility study for distal locking of femoral nails.

OBJECTIVES: Orthopaedic procedures that use fluoroscopy require intraoperative mental navigation of the surgical tools in a three-dimensional space. Moreover, because of their reliance on real-time monitoring, such procedures are frequently associated with increased x-ray exposure. The goal of this study was to develop a computer-guided surgical navigation system based on fluoroscopic images that not only facilitates direction of surgical tools within anatomy, but also provides constant feedback without the need for radiologic updates. To evaluate the feasibility of the new technology, the authors used it on cases requiring distal locking of femoral nails. METHODS: The hardware components of the system include an instrumented C-arm, optoelectronic position sensor, stereotactic tools, and custom-made software. Computer integration of these devices permitted C-arm alignment assistance and real-time navigation control without constant x-ray exposure. The nails were locked in a variety of media, including plastic femurs, dry human femoral specimens, human cadavers, and one clinical case. Unreamed femoral nail sizes ranged from 9/340 to 12/400. Radiographs were taken to confirm that screws were positioned correctly, and fluoroscopic time associated with the locking procedure was recorded. RESULTS: All distal holes were locked successfully. In eight (11 percent) of seventy-six holes, the drill bit touched the canal of the locking hole, albeit with no damage to the nail and no clinical consequences. The fluoroscopy time per pair of screws was 1.67 seconds. CONCLUSIONS: The developed system enables the physician to precisely navigate surgical instruments throughout the anatomy using just a few computer-calibrated radiographic images. The total radiation time per procedure can be significantly reduced because additional x-ray exposure is not required for tool navigation.

Bone Nails↗