Initial results with the unreamed AO tibial nail

It is generally accepted that intramedullary nailing in combination with reaming should be avoided in treating open fractures. However, the use of an unreamed, solid nail combined with interlocking also allows stabilization of open and complex fractures. 20 tibia fractures (65% open, 45% complex fractures) have been treated by the AO unreamed tibial nail (UTN), 12 (5 of them open fractures) by direct nailing and 8 after initial stabilization by an external fixator. In our series no intraoperative complications, no soft-tissue healing problems and no infections occurred. Thus, treatment of both open and comminuted fractures by UTN appears to be safe and generally needs no secondary stabilization.     

A simple jig to ease the insertion of distal screws in intramedullary locking nails

Distal locking of closed intramedullary nails can be time consuming and expose the surgeon to unnecessary increased ionization radiation. A simple jig is described which facilitates the insertion of the second distal locking screw, using the first drill hole as a pilot. This tool reduces the operating and the ionizing radiation exposure time.     

Clinical results of primary intramedullary osteosynthesis with the unreamed AO/ASIF tibial intramedullary nail of open tibial shaft fractures

From 04/91 to 06/96 sixty-nine open fractures of the tibia were primarily treated on the day of the accident with unreamed nailing (UTN, Synthese). The distributions of fracture type according to the AO classification and of soft tissue injury according to Gustilo were as follows: fracture type: A: 28%, B: 52%, C: 20%; soft tissue injury: I: 30%, II: 28%, IIIA: 12%, IIIB: 12%, IIIC: 6%. Of the 65 fractures assessed 46 (71%) healed within 18 weeks without secondary intervention. There was delayed healing in three fractures requiring secondary conversion to reamed nailing. Eight fractures (12%) developed pseudarthrosis of which five (8%) healed uneventfully. Deep infections was manifest in four fractures (6%). Three of these infections developed after secondary intervention to treat pseudarthrosis. Seven of the eight pseudarthroses and three of the four infections healed eventually. Revision procedures were necessary in 11 patients (17%) to deal with disturbed fracture healing or infection (10 reamed nailing procedures, three cancellous bone grafts, and one of each of the following: sequestrectomy, fibular osteotomy, plate fixation, external fixator, monorail procedure). The results show that the same good infection rates were achieved for the UTN as for the external fixator. The advantages of the UTN are, however, a lesser need for secondary intervention and greater patient comfort. Therefore, we find the UTN to be a good alternative to the external fixator in the treatment of open fractures with severe soft tissue damage.     

A comparison of a fluoroscopy-free mechanical targeting system and a free-hand technic for the placement of distal interlocking screws of tibial nails

Recently, radiation-independent aiming devices for the tibia which compensate for insertion-related implant deformation have been developed, but the benefits of such systems have not been determined. This study prospectively evaluated the duration of the nailing procedure, the length of radiation time, and the accuracy of interlocking screw placement with a radiation-independent distal aiming system and the free-hand technique. In an oblique cadaveric tibial fracture, a surgeon inexperienced with either technique performed a statically locked intramedullary nailing. For the aiming system and free-hand technique respectively, the total operation time was 25.4 +/- 11.3 vs 30.9 +/- 14.3 min (P = 0.029), the distal locking time was 16.7 +/- 8.6 vs 21.9 +/- 10.5 min (P = 0.004), the total fluoroscopy time was 9 +/- 5 vs 93 +/- 34 s (P < 0.0001), the distal locking fluoroscopy time was 0 versus 88 +/- 33 s (P < 0.0001), and the screw destruction was -0.7 +/- 5.2 vs 26.8 +/- 31.6 microns (P = 0.001). The failure rate was 1.6% (1 of 60 screws) in both groups. These results suggest that aiming devices can eliminate the need for radiation during distal interlocking screw placement.     

Development and initial clinical use of an aiming device for distal boring in interlocking nailing without roentgen image intensifier for the unreamed tibial nail

An aiming technique for an unreamed tibial nail was developed, which uses the relatively constant distance between the first transverse distal nail hole and the anterior aspect of the tibia. This aiming device is set at a distance of 12.3 mm from the anterior cortex, and fine tuning is finally resolved by use of a "working channel" with a 10 mm diameter from the medial side. The aiming system was tested in 20 cases in a video-documented prospective study using the unreamed tibial nail (UTN, Synthes) between July 1993 and March 1995. In all cases (100%) distal locking could be performed without image intensification. With a high percentage (55%) of open fractures (3 O3B fractures) the total operation time was 108 min (median, range 60-180 min). The time for distal locking (always 3 bolts) was 15.5 min (median, range 8.0-39.0 min), while the time for proximal locking (average 1.6 +/- 0.7 bolts) was 4.5 min (median, range 3.0-15.0 min). There were no major intra- or postoperative complications related to the aiming system. The major advantages are that it is not necessary to have image intensification for distal locking, there is a reduction in radiation exposure for the surgeon, and the drill holes are very precise.     

Biomechanical study of nine different tibia locking nails

We have previously found that T22 ([Tyr5, 12, Lys7]-polyphemusin II) exhibits strong anti-human immunodeficiency virus (HIV) activity comparable to that of 3'-azido-2', 3'-dideoxythymidine (AZT). The inhibition mechanism of T22 on HIV-replication has not been elucidated precisely yet, and hence the target molecules of T22 have not been identified. However, our recent research suggested that T22 exerts its effect by blocking virus-cell fusion at an early stage of HIV infection and that T22 might interact with an HIV envelope protein and/or a T-cell surface protein, both of which are critical for HIV infection. In this paper we demonstrated that T22 binds specifically to both gp120 (an envelope protein of HIV) and CD4 (a T-cell surface protein) and that both bindings can be inhibited by an anti-T22 antibody, using biosensor technology (BIAcoreTM) based on the principles of surface plasmon resonance. Linearization by the BIAcoreTM system (BIAlogue software) and nonlinear least squares analysis by curve fitting with exponential equations showed that both interactions have close dissociation constants (approximately 10(-7) M). The present study suggests that T22 inhibits the virus-cell fusion process through binding to both gp120 and CD4.     

The unreamed AO femoral intramedullary nail, advantages and disadvantages of a new modular interlocking system. A prospective study of 67 cases

The aim of this study was to investigate associations between sudden infant death syndrome (SIDS) and social factors in the Nordic countries. A case-control study was conducted in Denmark, Norway and Sweden: The Nordic Epidemiological SIDS Study. Parents of 244 SIDS infants and 869 control infants matched on gender, age at death and place of birth filled in questionnaires. The dataset was analysed by conditional logistic regression. In univariate analysis, the following sociodemographic factors were associated with an increased risk of SIDS: low maternal age [odds ratio (OR) 7.8; 2.8-21.5], high birth order (OR 4.4; 2.5-7.5), single motherhood (OR 2.9; 1.7-5.0), low maternal education (OR 4.5; 2.8-7.1), low paternal education (OR 3.0; 1.9-4.7), maternal unemployment (OR 2.4; 1.8-3.4) and paternal unemployment (OR 4.0; 2.7-5.9). In a multivariate analysis where maternal smoking was also included, only paternal unemployment, young maternal age and high birth order remained significantly associated with SIDS. Housing conditions were not associated with SIDS. However, the risk of SIDS was high if the family had lived in their present home for only a few years (OR 2.3; 1.3-4.1). Sociodemographic differences remain a major concern in SIDS in a low-incidence situation and even in an affluent population with adequate health services.     

Advantages of the unreamed tibial nail in comparison with external fixator in treatment of grade 3 B open tibial shaft fractures

Between 1987 and 1993, 41 grade 3B open tibial shaft fractures were treated with the unreamed tibial nail (URTN n = 22) or an external fixator (FIX n = 19). The method of treatment was left to the choice of the operating surgeon. Three below the knee amputations were performed, three patients died, and three were lost to follow-up. In all, 32 patients were followed up to union or at least for 1 year. There were no significant statistical differences between the two groups (P < 0.2, chi-squared, t-test) with respect to fracture type, fracture location, age, gender or accompanying injuries. The URTN group showed significantly better results regarding time to full weight-bearing (URTN 11 +/- 4 weeks; FIX 20 +/- 11 weeks, P < 0.01 M-W) Mann-Whitney Test, number of reoperations (URTN 1.04; FIX 2.89; P < 0.01 M-W), isolated bone grafting (URTN 3/22; FIX 8/19; P < 0.05 chi-squared), and average Karlstr?m and Olerud score (URTN 30 +/- 4; FIX 26 +/- 5; P < 0.05 M-W). In all, 15/17 URTN patients and only 6/15 FIX patients achieved unlimited walking distance (P < 0.01 M-W). Time to bony union, infection, and nonunion were not significantly different between groups.     

Type 2 fractures of the distal clavicle: a new surgical technique

A rare case of frontal sinus carcinoma is reported. The patient developed early recurrence following surgery, and was managed by accelerated hyperfractionated radiation therapy and concurrent cisplatinum-based systemic chemotherapy. The patient has remained disease-free for 30 months following the end of treatment.     

A simple technique for correction of complicated tibial deformity including rotational deformity

Although the simplest way to correct bone deformity is one-stage correction, the problem associated with that method is overstretching of the soft tissues, which limits the correction and leads to complications such as compartment syndrome or peripheral nerve palsy. If an adequate amount of tissue necessary for correction is formed in advance, the deformity can be corrected safely at one stage without overstretching of the tissues. A leg lengthening technique was employed to form the necessary tissues. After leg lengthening with an unilateral external fixator (Hifixator), deformities were corrected manually at one stage without anesthesia, and the corrected positions were again secured with the fixator. To correct rotational deformity, two sets of pins were inserted into the proximal bone fragment of the tibia at the time of the operation, and after lengthening the proximal pin clamp of the fixator was disconnected from one pin set and reconnected to the other set. We applied this method to four tibias of three patients without any complications. The tension of the tissues was monitored using a pressure sensor built into a Hifixator to prevent the tissues from overstretching. During and after the correction, the tension of the tissue was maintained at less than before the correction.     

AO external mini-fixateur for the hand bones. Surgical technique and initial experiences

Fractures of the hand and fingers showing comminution or associated soft-tissue lesions are best treated with external fixation. In contrast to other systems, the new AO mini-external fixator enables less bulky unilateral fixation facilitating early mobilisation and the special design of the double clamps allows preliminary intraoperative stabilisation with only one wire in each fragment. Modular fixation makes free placement of the wires possible with accommodation of bone and soft tissue lesions. Twenty patients with hand injuries showed uneventful soft tissue healing and there were no cases of non-union in 19 metacarpal and phalangeal fractures.     

A new technique for determining the denture tooth bond

As we learn more about hypertension, it is becoming increasingly apparent that conventional blood pressure measurements are fraught with potential error. Noninvasive ambulatory blood pressure monitoring is proving to be extremely valuable in both diagnosis and treatment. Advancing medical technology has provided small, noninvasive, reliable systems what are well tolerated by patients. The commercial availability of these systems facilitates their use in both clinical practice and in research. There have been legitimate concerns that continuous blood pressure monitoring may add considerably to the costs of diagnosing and treating hypertension. These worries, however, may be misplaced. If there are indeed as many patients being treated unnecessarily as has been suggested by many studies, then the money saved on drugs may well cover the costs of prolonged blood pressure monitoring. Moreover, many subjects can be spared unnecessary therapy. Although much work needs to be done with larger groups of patients followed over longer periods of time, the early experiences with 24-h ambulatory blood pressure monitoring have been extremely encouraging. These procedures have added to our understanding of hypertension and of the agents used in its treatment and are rapidly assuming an increasing importance in overall management.     

A new technique for positioning tangential fields

PURPOSE: A technique that eliminates the use of a mechanical "breast-bridge" for positioning tangential fields for treatment of the intact breast or chest wall has been developed. METHODS AND MATERIALS: Treatment set-up parameters are determined using measuring capabilities (gantry angles and source-skin distances) available on a standard simulator unit. A programmable scientific calculator is used to determine field geometry from polar coordinates for various points on the patient's skin. The calculator program determines the field size, a depth and lateral shift from a skin reference point to the isocenter for the tangential fields, and the gantry angles. The program provides additional information which facilitates the simulation process: First, the coordinates of the isocenter for the tangential fields are expressed relative to couch coordinates for an initial arbitrary isocenter so that the "auto go to" capability available on some simulators can be used. Second, the coordinates of the medial and lateral entry points can be edited when the first set of tangents are not accepted. This part of the program allows quick and efficient adjustment of the fields to obtain adequate treatment volume coverage and a minimum of irradiated lung or heart. RESULTS: Simulation of more than 300 patients has shown the technique to be a practical and efficient method for positioning tangential fields for breast or chest wall irradiation. CONCLUSION: The technique described here takes full advantage of the capabilities of the new generation of computer controlled simulators, and offers an alternative to previous methods employing a mechanical "breast-bridge."     

A new technique for rapid item analysis.

A rapid method of item analysis designed for use with Hankes-type (or Testscor) answer sheets is described. Whereas the item analysis of 25 versus 25 MMPI protocols usually takes… from 15 to 20 hours… use of the new method… [requires]… only four to five hours. (PsycINFO Database Record (c) 2010 APA, all rights reserved)