Biomedical subjects

C Krettek

Publications and source records attributed to C Krettek.

At least 145 records · Page 8Linked to original sources

PubMed2001

Heterotopic ossifications in patients after severe blunt trauma with and without head trauma: incidence and patterns of distribution.

OBJECTIVE: To investigate the incidence and distribution of heterotopic ossifications in patients with blunt multiple trauma with and without associated head trauma. DESIGN: Retrospective. SETTING: Level I trauma center. PATIENTS: Patients were included if they were treated between August 1987 and September 1995. Inclusion criteria included age between 16 and 65 years, injury severity score (ISS) of more than twenty points, and clinical reexamination performed more than three years after the initial injury. METHODS: The records of each patient were abstracted to determine the ISS, the Glasgow coma score (GCS), and parameters describing the course of intensive care. For each patient, a reexamination was performed between January and September 1998. Patients with multiple trauma and associated head trauma (Group PTH, polytrauma, GCS less than nine points, and head computed tomography scan abnormalities) and patients with multiple trauma without associated head trauma (Group PT, polytrauma, GCS of at least nine points, and normal head computed tomography scans) were compared. A clinical reexamination was performed to evaluate functional outcome. RESULTS: Sixty-four patients belonged to Group PTH and 124 patients belonged to Group PT. There were no differences in the age (Group PTH, 28.9 +/- 1.6 years; Group PT, 29.2 +/- 2.1 years) or severity of injury (ISS Group PTH, 31.0 +/- 5.3 points; ISS Group PT, 33.0 +/- 6.1 points) among patients in the two groups. The overall incidence of periarticular heterotopic ossification was comparable in patients with multiple trauma with and without head injury (Group PTH, 30 of 64 patients [46.9 percent]; Group PT, 53 of 124 patients [42.7 percent]). The duration of ventilation was significantly higher in Group PT (Group PTH, 9.3 +/- 2.4 days; Group PT, 14.2 +/- 3.1 days; p = 0.02). In the subgroups in which heterotopic ossification developed (PT-HO and PTH-HO), patients in PT-HO had a significantly higher incidence of heterotopic ossification, as compared with patients in PTH-HO at initially uninjured joints (Group PTH-HO, 1 of 30 patients [3.3 percent]; Group PT-HO, 10 of 53 patients [18.9 percent]; p = 0.04). CONCLUSIONS: There was a high incidence of heterotopic ossification around those joints that were initially classified as uninjured in patients without head trauma. This finding suggests that pathogenic pathways independent of head trauma, such as long-term ventilation, play a main role. Causative factors for the development of heterotopic ossification at initially uninjured joints in long-term ventilated patients with multiple trauma with and without head trauma remain to be elucidated.

Adult↗

PubMed2001

Major secondary surgery in blunt trauma patients and perioperative cytokine liberation: determination of the clinical relevance of biochemical markers.

BACKGROUND: The aim of this study is to assess the associations between the timing of secondary definitive fracture surgery on inflammatory changes and outcome in the patient with multiple injuries. The study population consists of a series of patients with multiple injuries who were managed using a strategy of primary temporary skeletal stabilization followed by delayed definitive fracture fixation. METHODS: In a prospective cohort study performed at a Level I trauma center, the patients' injuries and operative details as well as immune markers and clinical outcomes were studied. The patients were split into an early secondary surgery group (group ESS, surgery at days 2-4) and a late secondary surgery group (group LSS, surgery at days 5-8). During the posttraumatic course, inflammatory markers (interleukin [IL]-6, tumor necrosis factor-alpha) were determined on a daily basis. Perioperatively, these markers were additionally evaluated at 30 minutes, 7 hours, and 24 hours after initiation of surgery. RESULTS: Secondary surgery on days 2 to 4 was associated with a higher incidence of postoperative organ dysfunction (n = 33 [46.5%]) than secondary surgery on days 5 to 8 (n = 9 [15.7%], p = 0.01). A significant association between the combination of initial IL-6 values > 500 pg/dL plus surgery on days 2 to 4 and the development of multiple organ failure (r = 0.96, p < 0.001) occurred. A correlation between the initial IL-6 values > 500 pg/dL and surgery on days 5 to 8 (r = 0.57, p < 0.07) could not be found. IL-6 also demonstrated a predictive value for the development of multiple organ failure: IL-6 > 500 pg/dL in group ESS, r = 0.96, p < 0.001; IL-6 > 500 pg/dL in group LSS, r = 0.57, p < 0.07. CONCLUSION: According to our data, no distinct clinical advantage in carrying out secondary definitive fracture fixation early could be determined. In contrast, in patients who demonstrated initial IL-6 values above 500 pg/dL, it may be advantageous to delay the interval between primary temporary fracture stabilization and secondary definitive fracture fixation for more than 4 days. In patients with blunt multiple injuries undergoing primary temporary fixation of major fractures, the timing of secondary definitive surgery should be carefully selected, because it may act as a second hit phenomenon and cause a deterioration of the clinical status.

Adolescent↗

PubMed2001

Correlation between crash severity, injury severity, and clinical course in car occupants with thoracic trauma: a technical and medical study.

BACKGROUND: The crash mechanisms and clinical course of car occupants with thoracic injury were analyzed to determine prognostic factors and to create a basis for injury prophylaxis. METHODS: A technical and medical investigation of car occupants with a thoracic injury (Abbreviated Injury Scale-thorax [AIS(THORAX)] > or = 1) at the scene of the crash and the primary admitting hospital was performed. RESULTS: Between 1985 and 1998, 581 car occupants sustained a thoracic injury. Mean parameter values were as follows: AIS(THORAX), 2.5; Hannover Polytrauma Score (PTS), 21.4; Injury Severity Score (ISS), 24.2; Delta-v, 49.6 km/h (30.8 mph); and extent of passenger compartment deformation (DEF) (scale, 1--9), 4.0. In 19% (n = 112) of patients involved, the clinical course was evaluated: AIS(THORAX), 2.5; PTS, 20.0; ISS, 19.3; Delta-v, 50.1 km/h (31.1 mph); DEF, 3.9; intensive care unit time, 8.3 days; ventilation time, 5.7 days; and hospital stay, 15.3 days. In the groups with higher AIS(THORAX), ISS, PTS, and intensive care unit and ventilation time, higher Delta-v and DEF occurred. In patients with longer hospital stay, higher Delta-v, but no difference in DEF occurred. CONCLUSION: The injury severity and the clinical course demonstrated a positive correlation with the crash severity. Therefore, our technical accident analysis allows prediction of the severity of injury and the clinical course. It may consequently serve as a tool for development of more sophisticated injury prevention strategies and may improve passive car safety.

Abbreviated Injury Scale↗

PubMed2001

Head injury mechanisms in helmet-protected motorcyclists: prospective multicenter study.

BACKGROUND: In a prospective study, three research groups at Hannover (H) and Munich (M) in Germany and Glasgow (G) in the United Kingdom collected data from motorcycle crashes between July 1996 and July 1998 to investigate head injury mechanisms in helmet-protected motorcyclists. METHODS: The head lesions of motorcyclists with Abbreviated Injury Score-Head (AISHead) 2+ injuries and/or helmet impact were classified into direct force effect (DFE) and indirect force effect (IFE) lesions. The effecting forces and the force consequences were analyzed in detail. RESULTS: Two-hundred twenty-six motorcyclists (H, n = 115; M, n = 56; and G, n = 55) were included. Collision opponents were cars (57.8%), trucks (8.0%), pedestrians (2.3%), bicycles (1.4%), two-wheel motor vehicles (0.8%), and others (4.2%). In 25.4% no other moving object was involved. The mean impact speed was 55 km/h (range, 0-120 km/h) and correlated with AISHead. Seventy-six (33%) motorcyclists had no head injury, 21% (n = 48) AISHead 1, and 46% (n = 103) AISHead 2+. Four hundred nine head lesions were further classified: 36.9% DFE and 63.1% IFE. Lesions included 20.5% bone, 51.3% brain, and 28.1% skin. The most frequent brain lesions were subdural hematomas (22.4%, n = 47) and subarachnoid hematomas (25.2%, n = 53). Lesions of skin or bone were mainly DFE lesions, whereas brain lesions were mostly IFE lesions. CONCLUSION: A modification of the design of the helmet shell may have a preventative effect on DFE lesions, which are caused by a high amount of direct force transfer. Acceleration or deceleration forces induce IFE lesions, particularly rotation, which is an important and underestimated factor. The reduction of the effecting forces and the kinetic consequences should be a goal for future motorcycle helmet generations.

Accidents, Traffic↗

PubMed2001

Glycine reduces the inflammatory response and organ damage in a two-hit sepsis model in rats.

The goal of this study was to investigate whether prefeeding of glycine reduces the immunoinflammatory response, the degree of distant organ injury (liver), and/or the mortality rate in a two-hit model using intestinal ischemia/reperfusion and endotoxin (ET) challenge 6 h later in rats. The liver damage was greatest at 24 h after ET challenge and completely inhibited by glycine. The early systemic increase of the proinflammatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin (IL) -6 as well as the secretion of the antiinflammatory cytokine IL-10 was reduced by glycine. Tissue cytokine mRNA expression (TNF-alpha, IL-1beta, IL-10) was decreased in the lung and the liver but not in the mesenteric lymph node or ileum, in the glycine-fed group. However, glycine did not decrease the mortality rate. These results suggest that prefeeding of glycine reduces liver damage as well as the systemic and local (lung and liver) inflammatory response after intestinal ischemia/reperfusion and endotoxin challenge in rats.

Amino Acids↗

PubMed2001

Fractures and fracture dislocations of the midfoot: occurrence, causes and long-term results.

Etiology and outcome of 155 patients with midfoot fractures between 1972 and 1997 were analyzed to create a basis for treatment optimization. Cause of injuries were traffic accidents (72.2%), falls (11.6%), blunt injuries (7.7%) and others (5.8%). Isolated midfoot fractures (I) were found in 55 (35.5%) cases, Lisfranc fracture dislocations (L) in 49 (31.2%), Chopart-Lisfranc fracture dislocations (CL) in 26 (16.8%) and Chopart fracture dislocations (C) in 25 (16%). One hundred and forty eight (95%) of the midfoot fractures were treated operatively; 30 with closed reduction, 115 with open reduction, 3 patients had a primary amputation. Seven (5%) patients were treated non-operatively. Ninety seven (63%) patients had follow-up at an average of 9 (1.3-25, median 8.5) years. The average scores of the entire follow-up group were as follows: AOFAS - sum of all four sections (AOFAS-ET): 296, AOFAS-Midfoot (AOFAS-M): 71, Hannover Scoring System (HSS): 65, and Hannover Questionnaire (Q): 63. Regarding age, gender, cause, time from injury to treatment and method of treatment no score differences were noted (t-test: p>0.05). L, C or I showed similar scores and CL significantly lower scores (AOFAS-ET, AOFAS-M, HSS, Q). The highest scores in all groups were achieved in those fractures treated with early open reduction and operative fixation. Midfoot fractures, particularly fracture dislocation injuries, effect the function of the entire foot in the long-term outcome. But even in these complex injuries, an early anatomic (open) reduction and stable (internal) fixation can minimize the percentage of long-term impairment.

Adolescent↗

PubMed2001

Healing of the Achilles tendon: an experimental study.

Biomechanical properties of healing ruptures in the Achilles tendon of rabbits were examined after two, four, eight and 12 weeks. Treatment modalities were (n7): a) suture, b) fibrin-glue, c) non-surgical treatment. All animals received a functional aftertreatment consisting of a special orthotic support and free ambulation. For biomechanical testing a fixation-technique was applied that guaranteed intratendinous rupture. After two weeks, the tendons treated with fibrin glue showed better results (stiffness, maximum force to rupture, tensile stress to rupture) compared with the non-surgically treated group. The results for sutured tendons were in between those for the other groups. After four weeks, the results for sutured and for glued tendons were nearly equal and slightly better than the tendons in the non-surgical group. Late results revealed comparable biomechanical properties among all treatment groups and control tendons, suggesting our conclusion that non-surgical treatment is equal to repair using sutures or using fibrin glue as measured by stiffness and tensile stress.

Achilles Tendon↗

PubMed2000

Hepatic ischemia as a complication after correction of post-traumatic gibbus at the thoracolumbar junction.

STUDY DESIGN: This is a case report of hepatic ischemia secondary to celiac trunk stenosis as a complication after correction of a preoperative 30 degrees gibbus at the thoracolumbar junction. OBJECTIVES: A high index of suspicion is needed to make a timely diagnosis of hepatic ischemia in any setting. After spinal reconstruction involving lengthening, symptoms suggestive of an acute abdomen accompanied by markedly elevated liver enzymes should be evaluated with an angiogram to check for celiac trunk stenosis. SUMMARY OF BACKGROUND DATA: Review of the literature showed no reported cases of hepatic ischemia or descriptions of the status of celiac trunk stenosis after spinal surgery. Even in more commonly associated settings, diagnosis of both phenomena is often delayed, with possible morbid consequences. METHODS: A case is presented of a patient who underwent gibbus correction and re-establishment of lost anterior intervertebral distance at the thoracolumbar junction. After surgery, ischemic hepatitis, a perforated gallbladder, and splenic infarction developed secondary to celiac trunk stenosis-a result of cephalad displacement of the celiac trunk and compression of the artery by the diaphragmatic ligament. RESULTS: An emergent exploratory laparotomy with cholecystectomy was performed followed by an angiogram, which demonstrated stenosis of the celiac trunk. After release of the arcuate ligament, the patient's condition improved rapidly, and he made a complete recovery. CONCLUSIONS: The consequences of a delay in diagnosis of hepatic ischemia can be disastrous. An awareness of the possibility of this complication after spinal lengthening should facilitate a timely angiogram and operative intervention.

Adult↗

PubMed2000

Computer-assisted fluoroscopy-based reduction of femoral fractures and antetorsion correction.

OBJECTIVE: Intra-operative fluoroscopy is a valuable tool for visualizing underlying bone, implant, and surgical tool positions in orthopedics. It has brought about the minimally invasive surgical technique of intramedullar nailing to fix femoral shaft fractures. However, the limited field of view and two-dimensional property of fluoroscopic images aggravate intra-operative control of surgical parameters. The purpose of this article is to introduce a surgical navigation system based on fluoroscopy that provides missing information for the procedure of femoral fracture fixation. MATERIALS AND METHODS: Optoelectronic markers are placed on a surgical drill, involved bone fragments, the femoral nail, and the fluoroscope to track their positions. Projection properties of the fluoroscope are acquired through an initial precalibration. The relative positions of bone fragments, implants, and surgical tools are displayed superimposed simultaneously and in real time on multi-planar intra-operative fluoroscopic images. This is achieved by computer simulation of X-ray projections that have taken place with acquisition of the fluoroscopic images. In addition, a method has been developed that allows contactless measurement of three-dimensional anatomic landmarks, based on their representation in fluoroscopic images. In combination with optoelectronic tracking, this enables dynamic calculation of important surgical parameters such as femoral antetorsion. RESULTS: A pilot surgery showed that fracture reduction can benefit from the developed computer-assisted method. An in-vitro study on computer-assisted measurement of femoral antetorsion demonstrated the high degree of precision of this technique.

Bone Nails↗

PubMed2000

[Distal fractures of the femur].

Supracondylar femoral fractures still present a challenge to the treating surgeon. The incidence of delayed and non-unions is reduced due to the minimally invasive plating techniques, but establishing a correct axis and good function is still a problem. During the last few years new implants have been developed to allow less difficult operative techniques in minimally invasive surgery. The Less Invasive Stabilization System (LISS) is a percutaneous plating system with monocortical self-drilling screws. The screws are inserted with an aiming guide and form a stable angle with the plate. The distal femoral nail allows placement of a spiral blade in the nail, thereby enhancing the interlocking stability.

Adult↗

PubMed2000

Whiplash-type neck distortion in restrained car drivers: frequency, causes and long-term results.

An analysis was made of 1176 whiplash-type neck distortions taken from a total of 3838 restrained car driver incident reports. The percentage of whiplash-type neck distortion among injured drivers increased from less than 10% in 1985 to over 30% in 1997. Most occurred in head-on crashes or crashes with multiple collisions; only 15% occurred in rear-end collisions. More than 1,000 questionnaires were sent to the injured to find out about the duration and type of complaints caused by their cervical spine injury. Although only 138 (12%) returned the questionnaire, which may not be a representative sample, a further analysis was carried out. Of the 138, 121 (88%) indicated that they had suffered or were still suffering from their symptoms. The percentages of the various complaints were as follows: pain (74%), tension (6%) and stiffness (5%) in the head (27%), neck (55%) and shoulder (8%). The duration of the complaints was longest after multiple collisions and when the onset of complaints was longer than 24 h after trauma. Women and elderly persons predominated slightly in the group with longer duration of complaints. A correlation between the severity of the accompanying injuries and duration of complaints was found. Lack of adequate follow-up for patients with less severe injuries posed considerable difficulties for this retrospective study. In order to better evaluate this problem, prospective studies are necessary, with documentation including diagnosis, treatments, complaint duration and type.

Accidents, Traffic↗

PubMed2000

Biomechanics of femoral interlocking nails.

Today there is a variety of different interlocking intramedullary nail designs available for the femur. We compared different nail types in the bone implant complex (BIC) of four unreamed solid nails and a slotted reamed nail with simulated comminuted mid shaft fractures to see if there are major differences in stiffness for axial load, bending and torsion. The fractures were simulated by a 2 cm defect osteotomy in paired human cadaver femora. Each bone was tested intact in a universal testing machine, osteotomy and osteosynthesis were performed, and the BIC was tested. Relative stiffness was calculated. In torque testing the unslotted solid nail showed significantly more stiffness (0.6-1.8 Nm/degrees) compared to the slotted nail (0.2 Nm/degrees). Compared to intact bone (6.9 Nm/degrees), both groups of nails were significantly less stiff (relative stiffness 2-20%). In axial load and bending testing the large diameter unreamed nail showed significantly higher stiffness (32-68%). This study shows that stiffness of bone implant complex in interlocking femoral nails is more dependent on nail profile than on the pressfit of nails in the medullary canal.

Adult↗

PubMed2000

Hip dislocation in patients with multiple injuries. A followup investigation.

The combination of traumatic hip dislocation and multiple trauma have not been well documented in the medical literature to date. The role of surgery therefore has not been well defined in these patients. During a 12-year period, 29 consecutive patients with 31 traumatic hip dislocations with concomitant Injury Severity Scores exceeding 18 points were treated at the authors' institution. An initial satisfactory closed reduction was achieved in 23 patients, two patients had failed reductions, and four patients had noncongruous reductions. Open surgical procedures were done on these patients and on 10 additional patients who had associated acetabular or femoral head fractures. Overall, seven patients from the group died including two patients who had surgical procedures. From 17 living patients who did not require surgery for failed or noncongruous reductions, 13 patients were available for followup at a mean of 8 years after their injury. The clinical results at this followup were excellent in three hips, good in seven hips, and fair in four hips. The radiologic results, however, showed that five patients had early (Grades I and II according to Matta) hip degeneration and seven patients had Grade II (according to Ficat) avascular necrosis of the femoral head. These changes were not clinically significant at this followup and it is proposed that these results justify a policy of active treatment of traumatic hip dislocation in patients with multitrauma.

Adolescent↗

PubMed2000

Biochemical changes after trauma and skeletal surgery of the lower extremity: quantification of the operative burden.

OBJECTIVE: To quantify changes in variables of inflammation, coagulation, and fibrinolysis in blunt trauma patients with lower extremity fractures who underwent different types of surgical procedures. DESIGN: Prospective, cohort study. SETTING: Level I university trauma center. PATIENTS: We allocated 83 blunt trauma patients in stable condition and 22 patients eligible for elective hip replacement to four treatment groups. INTERVENTIONS: In 34 multiply traumatized patients with femoral fracture (group PTFF) and in 28 patients with an isolated femoral fracture (group IFF), primary unreamed intramedullary nailing for stabilization of the femoral shaft fracture was performed. In 22 patients, an elective uncemented total hip arthroplasty (group THA) was inserted for osteoarthritis, and in 21 control patients, an isolated ankle fracture (group AF) was acutely stabilized. MEASUREMENTS AND MAIN RESULTS: From serially sampled central venous blood, the perioperative concentrations of interleukin (IL)-6, of tumor necrosis factor-alpha, of prothrombin fragments 1 + 2, and of D-dimer cross-linked fibrin degradation products were evaluated. Intramedullary instrumentation for an isolated femur fracture caused a significant perioperative increase in the concentrations of IL-6 (preoperative IL-6, 52 +/- 12 pg/mL; IL-6 30 mins postinsertion, 78 +/- 14 pg/mL; p = .02). This increase was comparable with group THA (preoperative IL-6, 46 +/- 16 pg/mL; IL-6 30 mins postinsertion, 67 +/- 11 pg/mL; p = .03). A positive correlation occurred between both groups (r = .83, p < .0004). Multiple trauma patients demonstrated significantly (p = .0002) higher IL-6 concentrations than all other groups throughout the study period and showed a significant increase after femoral nailing (preoperative IL-6, 570 +/- 21 pg/mL; IL-6 30 mins postinsertion, 690 +/- 24 pg/mL; p = .003), whereas no perioperative change was seen in group AF. The highest IL-6 increases were associated with a longer ventilation time (group PTFF) and a longer period of positive fluid balances (groups PTFF, IFF, THA). The coagulatory variables demonstrated similar perioperative increases in groups IFF and THA, but not in groups PTFF and AF. The IL-6 concentrations and the prothrombin fragments 1 + 2 concentrations correlated between groups THA and IFF at 30 mins and at 1 hr after surgery (r2 = .64, p < .02). In all patients the clinical variables were stable perioperatively. CONCLUSIONS: Major surgery of the lower extremity causes changes to the inflammatory, fibrinolytic, and coagulatory cascades in patients with stable cardiopulmonary function. The inflammatory response induced by femoral nailing is biochemically comparable to that induced by uncemented total hip arthroplasty. In multiple trauma patients, increases, which occurred in addition to those induced by the initial trauma, were measured. Definitive primary femoral stabilization by intramedullary nailing imposes an additional burden to the patient with blunt trauma. A careful preoperative investigation is required to evaluate whether primary definitive stabilization can be performed safely.

Adult↗

PubMed2000

Appraisal of early evaluation of blunt chest trauma: development of a standardized scoring system for initial clinical decision making.

BACKGROUND: Current techniques for assessment of chest trauma rely on clinical diagnoses or scoring systems. However, there is no generally accepted standard for early judgement of the severity of these injuries, especially in regards to related complications. This drawback may have a significant impact on the management of skeletal injuries, which are frequently associated with chest trauma. However, no convincing conclusions can be determined until standardization of the degrees of chest trauma is achieved. We investigated the role of early clinical and radiologic assessment techniques on outcome in patients with blunt multiple trauma and thoracic injuries and developed a new scoring system for early evaluation of chest trauma. METHODS: A retrospective investigation was performed on the basis of 4,571 blunt polytrauma (Injury Severity Score [ISS] > or = 18) patients admitted to our unit. Inclusion criteria were treatment of thoracic injury that required intensive care therapy, initial Glasgow Coma Scale score greater than 8 points, and no local or systemic infection. Patients with thoracic trauma and multiple associated injuries (ISS > or = 18) were included. In all patients, the association between various parameters of the thoracic injuries and subsequent mortality and morbidity was investigated. RESULTS: A total of 1,495 patients fulfilled the inclusion criteria. Patients' medical records and chest radiographs were reevaluated between May 1, 1998, and June 1, 1999. The association between rib fractures and chest-related death was low (> three ribs unilateral, mortality 17.3%, odds ratio 1.01) unless bilateral involvement was present (> three ribs bilateral, mortality 40.9%, odds ratio 3.43). Injuries to the lung parenchyma, as determined by plain radiography, were associated with chest-related death, especially if the injuries were bilateral or associated with hemopneumothorax (lung contusion unilateral, mortality 25.2%, odds ratio 1.82; lung contusion bilateral + hemopneumothorax, mortality 53.3%, odds ratio 5.1). When plain anteroposterior chest radiographs were used, the diagnostic rate of rib fractures (< or = three ribs) increased slightly, from 77.1% to 97.3% during the first 24 hours of admission. In contrast, pulmonary contusions were often not diagnosed until 24 hours after admission (47.3% at admission, 92.4% at 24 h, p = 0.002). A new composite scoring system (thoracic trauma severity score) was developed that combines several variables: injuries to the chest wall, intrathoracic lesions, injuries involving the pleura, admission PaO2/FIO2 ratio, and patient age. The receiver operating characteristic curve demonstrated an adequate discrimination, as demonstrated by a value of 0.924 for the development set and 0.916 for the validation set. The score was also superior to the ISS (0.881) or the thorax Abbreviated Injury Score (0.693). CONCLUSION: Radiographically determined injuries to the lung parenchyma have a closer association with adverse outcome than chest-wall injuries but are often not diagnosed until 24 hours after injury. Therefore, clinical decision making, such as about the choice of surgery for long bone fractures, may be flawed if this information is used alone. A new thoracic trauma severity score may serve as an additional tool to improve the accuracy of the prediction of thoracic trauma-related complications.

Adolescent↗

PubMed1999

A mechanical distal aiming device for distal locking in femoral nails.

Although the free hand technique remains the most popular method for distal interlocking screw insertion, proximally mounted radiation independent devices that compensate for implant deformation recently have been developed for the femur. However, the benefits of such systems have not been determined. This study prospectively compared the duration of the nailing procedure, the length of radiation time, and the accuracy of interlocking screw placement when using a radiation independent distal aiming system with those using the free hand technique. In 20 paired intact anatomic specimen femurs, one surgeon experienced only in the free hand technique performed statically locked intramedullary nailing using the two methods. For the aiming system and free hand technique, respectively, the total operation time was 19.1 +/- 8.4 minutes versus 20.9 +/- 11.3 minutes, the distal locking time was 6.6 +/- 2.4 minutes versus 4.8 +/- 1.5 minutes, the total fluoroscopy time was 23 +/- 17 seconds versus 69 +/- 34 seconds, and the distal locking fluoroscopy time was 0 versus 37 +/- 15.5 seconds. There were no failures in either group. Drill nail contact and distal screw damage were greater with the free hand technique. This study suggests that the main advantages of the aiming arm compared with the free hand technique include the elimination of radiation during distal interlocking and more precise screw placement with decreased insertion related hardware damage.

Aged↗

PubMed1999

Minimally invasive plate osteosynthesis: does percutaneous plating disrupt femoral blood supply less than the traditional technique?

OBJECTIVES/HYPOTHESIS: Proximal and distal femur fractures have traditionally been treated with open reduction and internal fixation through a standard lateral approach. New, "minimally invasive" internal fixation techniques, however, have been developed in an effort to devascularize the bone less than the traditional method. The purpose of this study was to determine whether a minimally invasive percutaneous plating technique better preserves bone vascularity relative to the traditional method by comparing the effect of the two approaches on the blood supply of the distal femur using silicone arterial dye injection in a cadaveric model. STUDY DESIGN/METHODS: Ten fresh human cadavers underwent lateral conventional plate osteosynthesis (CPO) through a standard lateral approach on one side and minimally invasive plate osteosynthesis (MIPO) through two three-centimeter incisions on the contralateral side. After injection of silicone dye, a dissection was performed bilaterally to identify the femoral perforating and nutrient arteries. RESULTS: All MIPO specimens showed intact perforating and nutrient arteries, whereas the CPO specimens had a variable incidence of vessel disruption. The MIPO group demonstrated better periosteal perfusion in each of the cadavers and improved medullary perfusion in 70 percent of the MIPO specimens compared with the CPO specimens. CONCLUSION: A percutaneous minimally invasive plating technique disrupts the femoral blood supply less than the traditional open method. Such minimally invasive methods may be more advantageous biologically than the traditional method.

Aged↗

PubMed1999

The mechanical effect of blocking screws ("Poller screws") in stabilizing tibia fractures with short proximal or distal fragments after insertion of small-diameter intramedullary nails.

OBJECTIVES/HYPOTHESIS: To evaluate the mechanical effects of medial and lateral blocking screws in supplementing intramedullary nail fixation of high proximal and low distal tibial fractures treated with small-diameter intramedullary nails. STUDY DESIGN: Intact fresh human cadaveric tibiae were sectioned to provide ten distal segments measuring seventy millimeters and ten proximal segments measuring ninety millimeters. In the distal segments, stainless steel solid eight-millimeter tibial nails were advanced to eight millimeters from the ankle joint. Two transverse and one anterior-posterior (AP) locking screw were inserted using a custom-made jig. The same jig was used for the placement of a medial and a lateral blocking screw (BS) in the AP direction, nine millimeters above the superior most interlocking screw and eight millimeters distal to the lower end of the segment. In the proximal segments, two interlocking screws (both static and dynamic screws) were placed in a medial-lateral direction with the use of the insertion handle. A jig was used for placement of a medial and a lateral BS in the AP direction, nine millimeters below the lower transverse interlocking screw and sixteen millimeters proximal to the lower end of the segment. The bone-implant construct (BIC) was embedded and fixed in a materials testing machine. The BICs were loaded in the medial-lateral direction at a distance of 185 millimeters from the nail ends with loads from -150 newtons to + 150 newtons. Force-displacement curves were recorded before and after insertion of the BSs. RESULTS: In proximal BICs, the addition of BSs decreased the deformation of the BICs 25 percent, from 8.9 +/- 1.9 degrees [mean +/- standard deviation (SD)] in the control group to 6.8 +/-1.1 degrees in the BS group (mean +/- SD) (p < 0.0001). In distal BICs, the addition of BSs decreased the deformation of the BICs 57 percent, from 9.5 +/- 1.4 degrees (mean +/- SD) in the control group to 4.0 +/- 1.0 degrees in the BS group (mean +/- SD) (p < 0.0001). CONCLUSIONS: The study suggests that medial and lateral blocking screws can increase the primary stability of distal and proximal metaphyseal fractures after nailing and can be an effective tool for selected cases that exhibit malalignment and/or instability.

Aged↗