• Journal of Korean Neurosurgical Society
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• v.30 no.10
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• pp.1210-1219
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• 2001

Introduction : The purpose of this study was to analyze the safety, pullout strength and radiographic characteristics of unicortical and bicortical screws of cervical facet within cadaveric specimens and evaluate the influence of level of training on the positioning of these screws. Methods : Twenty-one cadavers, mean 78.9 years of age, underwent bilateral placement of 3.5mm AO lateral mass screw from C3-C6(n=168) using a slight variation of the Magerl technique. Intraoperative imaging was not used. The right side(unicortical) utilized only 14mm screws(effective length of 11mm) while on the left side to determine the length of the screw after the ventral cortex had been drilled. Three spine surgeons(attending, fellow, chief resident) with varying levels of spine training performed the procedure on seven cadavers each. All spines were harvested and lateral radiographs were taken. Individual cervical vertebrae were carefully dissected and then axial radiographs were taken. The screws were evaluated clinically and radiographically for their safety. Screws were graded clinically for their safety with respect to the spinal cord, facet joint, nerve root and vertebral artery. The grades consisted of the following categories : "satisfactory", "at risk" and "direct injury". Each screw was also graded according to its zone placement. Screw position was quantified by measuring a sagittal angle from the lateral radiograph and an axial angle from the axial radiograph. Pull-out force was determined for all screws using a material testing machine. Results : Dissection revealed that fifteen screws on the left side actually had only unicortical and not bicortical purchase as intended. The majority of screws(92.8%) were satisfactory in terms of safety. There were no injuries to the spinal cord. On the right side(unicortical), 98.9% of the screws were "satisfactory" and on the left side(bicortical) 68.1% were "satisfactory". There was a 5.8% incidence of direct arterial injury and a 17.4% incidence of direct nerve root injury with the bicortical screws. There were no "direct injuries" with the unicortical screws for the nerve root or vertebral artery. The unicortical screws had a 21.4% incidence of direct injury of the facet joint, while the bicortical screws had a 21.7% incidence. The majority of "direct injury" of bicortical screws were placed by the surgeon with the least experience. The performance of the resident surgeon was significantly different from the attending or fellow(p<0.05) in terms of safety of the nerve root and vertebral artery. The attending's performance was significantly better than the resident or fellow(p<0.05) in terms of safety of the facet joint. There was no relationship between the safety of a screw and its zone placement. The axial deviation angle measured $23.5{\pm}6.6$ degrees and $19.8{\pm}7.9$ degrees for the unicortical and bicortical screws, respectively. The resident surgeon had a significantly lower angle than the attending or fellow(p<0.05). The sagittal angle measured $66.3{\pm}7.0$ degrees and $62.3{\pm}7.9$ degrees for the unicortical and bicortical screws, respectively. The attending had a significantly lower sagittal angle than the fellow or resident(p<0.05). Thirty-three screws that entered the facet joint were tested for pull-out strength but excluded from the data because they were not lateral mass screws per-se and had deviated substantially from the intended final trajectory. The mean pull-out force for all screws was $542.9{\pm}296.6N$. There was no statistically significant difference between the pull-out force for unicortical($519.9{\pm}286.9N$) and bicortical($565.2{\pm}306N$) screws. There was no significant difference in pull-out strengths with respect to zone placement. Conclusion : It is our belief that the risk associated with bicortical purchase mandates formal spine training if it is to be done safely and accurately. Unicortical screws are safer regardless of level of training. It is apparent that 14mm lateral mass screws placed in a supero-lateral trajectory in the adult cervical spine provide an equivalent strength with a much lower risk of injury than the longer bicortical screws placed in a similar orientation.

• Journal of Korean Academy of Nursing
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• v.18 no.2
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• pp.197-210
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• 1988

The purposes of this study were : 1) to assess the level of pain and to identity the varieties and the degree of pain-related behavior, 2) to measure the level of correlation between the level of pain and the degree of pain- related behavior, 3) to test the correlation between the Korean Pain Rating Scale (KPRS) and Graphic Rating Scale(GRS), and 4) to gather data relevant to the Socio-demographic status of the subjects. The level of pain was measured by KPRS and GRS developed by the researchers. The KPRS consists of three dimensions ; the sensory, the affective and the miscellaneous and the GRS of two separate scales ; the intensity scale and the unpleasantness scale. Of the 2, 025 who had visited orthopedic and neurosurgical out-patients department of 11 university hospitals in various districts of Korea with the episode of Joint pain, 405 subjects were self-selected by responding to the data gathering tools and questionaires mailed. The results are summaried as follows : 1. Maale(217, 53.6%) exceeded female patients(188, 46.4%) in number and the onset of joint pain was more prevalent in the age groups of the 20s and the 30s. 160(39.5%) had been hospitalized for the treatment of, and 87(21.5%) had retired because of the joint pain. 2. Mean pain score measured by KPRS was 128.31 (range; 0-1.344.8) ; mean sensory score was 43.23(range ; 0-645.88%), mean affective score was 46.09(range ; 0- 356.72), and mean miscellaneous score was 39.99(range ; 0-341.68). Mean pain scores measured by GRS were ; sensory intensity score ; 109.1(range ; 0-200) and distress score ; 99.1 (range ; 0-200). 3. The prevalent sites of joint pain revealed to be the right knee joint(203; 50.1%), left knee joint(181(44.7%), left ilium(147, 36.3%), lumbar region (106; 26.2%), hip joint(92; 22.7%) and the ankle(84; 20.7%). 4. The average sleep hour was 6.8hours per day and the average rest hour during the day hours was 3.3hours (range 0-20). 5. The average duration of suffering from joint pain was 49.1 months. 6. Most of the subjects(298; 73.6%) used some sorts of pain relieving practices ; the most prevalent pain relieving practice was the compliance with the physician prescribed treatments(34.4%). 7. The level of discomfort in carrying out the ADL(activities of daily living was 101.16(38.83) and the level of needs for aid in carrying out the ADL was 76.62(31.79). 8. The interrelation between KPRS total score and GRS sensory intensity score(.4438), as well as that of GRS distress score(r＝.4446) were not highly correlated, however, sensory and affective dimension within KPRS (.7547) and pain intensity and distress score of GRS(.6975) revealed moderate intercorrelation. 9. Pain-related behaviors such as discomfort in carrying out ADL, the need for aids in carrying out ADL, frequency of pain relieving practices, varieties of pain sites and length of rest hours during the day hours revealed to be highly correlated with the level of pain measured by KPRS, GRS sensory intensity scale and GRS distress scale. The following are recommended ; 1. Test for the correlation of KPRS total score and the summated score of GRS ; sensory intensity and distress scores. 2. Possibilities of utilization of the pain-related behaviors which revealed high correlation as indirect assessment tool for measuring the level of pain.

• Quality Improvement in Health Care
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• v.4 no.1
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• pp.50-63
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• 1997

Background : A pressure sore was defined as any skin lesion caused by unrelieved pressure and resulting in damage to underlying tissue. The health care institutions in the United States were reported the incident rate of pressure sores ranging from 6 to 14 %. Intensive Care Unit needed highest quality of care has been found over 40% incidence rate of pressure sore. Also, Annual expenditures for the care of pressure sores in patients in the United States have been estimated to be $7.5 billion; furthermore, 50 percent more nursing time is required to care for patients with pressure sore in comparison to the time needed to implement preventive measures against pressure sore formation. However, In Korea, there were little reliable reports, or researches, about incidence rates of pressure sore in health care institution including intensive care unit and about the integrated approach like CQI action team for risk assessment, prevention and treatment of pressure ulcers. Therefore, this study was to develop pressure sore risk assessment tool and the protocol for prevention of pressure sore formation through CQI action team activities, to monitor incident rate of pressure sore and the length of sore formation for patients at high risk, and to approximately estimate nursing time for sore dressing during research period as the effect of CQI action team. Method : CQI action team in intensive care unit, launched since early 1996, reviewed the literature for the standardized risk assessment tool, developed the pressure sore assessment tool based on the Braden Scale, tested its validity, compared on statistics including incidence rate of pressure sore for patients at high risk. Throughout these activities, CQI action team was developed the protocol, called as St. Marys hospital Intensive Care Unit Pressure Sore Protocol, shifted the emphasis from wound treatment to wound prevention. After applied the protocol to patients at high risk, the incident rate and the period of prevention against pressure development were tested with those for patients who received care before implementation of protocol by Chi-square and Kaplan-Meier Method of Survival Analysis. Result : The CQI action team found that these was significant difference of in incidence rate of pressure sores between patients at high risk (control group) who received care before implementation of protocol and those (experimental group) who received it after implementation of protocol (p<.05). 25% possibility of pressure sore formation was shown for the patients with 6th hospital day in ICU in control group. In experimental group, the patients with 10th hospital day had 10% possibility of pressure sore. Therefore, there was significant difference(p<.05) in survival rate between two groups. Also, nursing time for dressing on pressure sore in experimental group was decreased as much as 50% of it in control group. Conclusion : The collaborative team effort led to reduced incidence, increased the length of prevention against pressure sore, and declined nursing care times for sore dressing. However, there have had several suggestions for future study. The preventive care system for pressure sore should be applied to patients at moderate, or low risk throughout continuous CQI team activities based on Bed Sore Indicator Fact Sheet. Hospital-wide supports, such as incentives, would be offered to participants for keeping strong commitment to CQI team. Also, Quality Information System monitoring incidents and estimating cost of poor quality, like workload (full time equivalence) or financial loss, regularly in a hospital has to be developed first for supporting CQI team activities as well as empowering hospital-wide QI implementation. Being several limitations, this study would be one of the report cards for the CQI team activities in intensive care unit of an acute hospital and a trial of quality improvement of health care in Korea.