How Long Does Antimycobacterial Antibiotic-loaded Bone Cement Have In Vitro Activity for Musculoskeletal Tuberculosis?

BACKGROUND: Antibiotic-loaded bone cement is accepted as an effective treatment modality for musculoskeletal tuberculosis. However, comparative information regarding combinations and concentrations of second-line antimycobacterial drugs, such as streptomycin and amoxicillin and clavulanic acid, are lacking. QUESTIONS/PURPOSES: (1) In antibiotic-loaded cement, is there effective elution of streptomycin and Augmentin® (amoxicillin and clavulanic acid) individually and in combination? (2) What is the antibacterial activity duration for streptomycin- and amoxicillin and clavulanic acid -loaded cement? METHODS: Six different types of bone cement discs were created by mixing 40 g bone cement with 1 or 2 g streptomycin only, 0.6 g or 1.2 g Augmentin® (amoxicillin and clavulanic acid) only, and a combination of 1 g streptomycin plus 0.6 g amoxicillin and clavulanic acid and 2 g streptomycin plus 1.2 g amoxicillin and clavulanic acid. Five bone discs of each type were incubated in phosphate buffered saline for 30 days with renewal of the phosphate buffered saline every day. The quantity of streptomycin and/or amoxicillin and clavulanic acid in eluates were measured by a liquid chromatography-mass spectrometry system, and the antimycobacterial activity of eluates against Mycobacterium tuberculosis H37Rv, were calculated by comparing the minimal inhibitory concentration of each eluate with that of tested drugs using broth dilution assay on microplate. RESULTS: Streptomycin was detected in eluates for 30 days (in 1 g and 2 g discs), whereas 1.2 g amoxicillin and clavulanate eluted until Day 7 and 0.6 g amoxicillin and clavulanate until Day 3. All eluates in streptomycin-containing discs (streptomycin only, and in combination with amoxicillin and clavulanic acid) had effective antimycobacterial activity for 30 days, while amoxicillin and clavulanate-only preparations were only active until Day 14. The antimycobacterial activity of eluates of 2 g streptomycin plus 1.2 g amoxicillin and clavulanate were higher than those of discs containing 1 g streptomycin plus 0.6 g amoxicillin and clavulanate until Day 3, without differences (Day 3, 1 g streptomycin plus 0.6 g amoxicillin and clavulanate: 17.5 ± 6.85 ug/mL; 2 g streptomycin plus 1.2 g amoxicillin and clavulanate: 32.5 ± 16.77 ug/mL; p = 0.109). After Day 7, however, values of the two combinations remained no different than that of Day 30 (Day 30, 1 g streptomycin plus 0.6 g amoxicillin and clavulanate: 0.88 ± 0.34 ug/mL; 2 g streptomycin plus 1.2 g amoxicillin and clavulanate: 0.59 ± 0.94 ug/mL; p = 0.107). CONCLUSIONS: Streptomycin, in the form of antibiotic-loaded bone cement, had effective elution characteristics and antimycobacterial effects during a 30-day period, whereas amoxicillin and clavulanate only had effective elution and antimycobacterial characteristics during the early period of this study. The two drugs did not interfere with each other during the elution test. CLINICAL RELEVANCE: This research revealed that combinations of streptomycin and amoxicillin and clavulanate mixed with bone cement are effective for 30 days. Further trials to determine various different combinations of drugs are necessary to improve the effectiveness of treatments for musculoskeletal tuberculosis.

Femur bowing could be a risk factor for implant flexion in conventional total knee arthroplasty and notching in navigated total knee arthroplasty.

PURPOSE: This study aimed to investigate the relationship between preoperative femoral axes and femoral implant position and to determine how femoral sagittal axes, including femoral anterior bowing, influence the femoral component position in total knee arthroplasty (TKA). METHODS: The relationship between femoral axes (femoral anterior bowing, mechanical axis and the anterior cortical line, intramedullary axis) and implant position was compared in 50 conventional and 50 navigated TKAs. Outliers with more than a 3° margin of error in placement of the femoral component compared with the mechanical axis in the sagittal plane were calculated. RESULTS: The femoral component flexion angle was 3.1° in the conventional group and 1.6° in the navigation group (p < 0.001). Anterior femoral bowing correlated positively with the angle between the mechanical axis and implant (r = 0.360, p = 0.010) in the conventional group and negatively with the angle between the anterior cortical line and flange of the femoral component (r = -0.355, p = 0.010) in navigated TKAs. Incidence of outliers was 48 % (24 patients) in the conventional group compared with 10 % (five patients) in the navigated group (p = 0.008). CONCLUSIONS: Femoral anterior bowing was an influential factor for implant position and could be a risk factor for both femoral implant flexion in conventional TKAs and notching in navigated TKAs. The results of this study should be considered by surgeons when assessing the risk factors for femoral geometry before performing TKAs, as these results may help them to avoid an overly flexed or extended position of the femoral component, which would affect clinical long-term survival. LEVEL OF EVIDENCE: Retrospective comparative study, Level III.

Is Electrocautery of Patella Useful in Patella Non-Resurfacing Total Knee Arthroplasty?: A Prospective Randomized Controlled Study.

There is controversy over the need for electrocauterization of the patella in non-resurfacing total knee arthroplasty (TKA). We investigated whether this procedure is beneficial through a prospective randomized controlled trial. Fifty patients who underwent electrocautery were compared with 50 patients who did not undergo this procedure. We determined cartilage status, preoperative and postoperative American Knee Society (AKS) score, the Western Ontario and McMaster Universities score (WOMAC) and the Patellofemoral (PF) scores for a minimum of 5 years. The two groups did not differ significantly in demographics, intraoperative cartilage status, or preoperative or postoperative outcomes. No complications were detected in either group. We found no benefits of electrocautery of the patella in patellar non-resurfacing TKA up to 5 years.

Correlation between metabolic syndrome and knee osteoarthritis: data from the Korean National Health and Nutrition Examination Survey (KNHANES).

BACKGROUND: This study was designed to investigate the correlations of knee osteoarthritis (OA) with metabolic syndrome (MetS) and MetS parameters in Korean subjects. METHODS: This study included data from 270 subjects with knee OA and 1964 control subjects with a mean age of 54.56 (SD 11.53) years taken from the Korean National Health and Nutritional Examination Survey (KNHANES) 2008. Multivariate logistic regression analysis was conducted to examine possible associations for knee OA with MetS and MetS parameters. RESULTS: MetS was shown to be associated with an increased risk of knee OA in female subjects in unadjusted analysis (OR 1.798, 95% CI 1.392, 2.322), but this significance disappeared when adjusted for confounding factors (OR 1.117, 95% CI 0.805, 1.550). No significant association between MetS and knee OA was found in male subjects. Among parameters of MetS, only high waist circumference (WC) in female subjects was significantly associated with an increased prevalence of knee OA, even after adjusting for confounding factors, while no other significant associations were found in both male and female subjects. CONCLUSION: We found that WC was associated with knee OA in female subjects, but neither MetS nor any parameters thereof were shown to be associated with knee OA in the Korean subjects of this study. Although we found no relationship between a pre-inflammatory state of MetS and knee OA, we believe further investigation of this relationship in various aspects is warranted, as MetS may also be a risk factor for complications in knee OA related procedures.

Isoniazid could be used for antibiotic-loaded bone cement for musculoskeletal tuberculosis: an in vitro study.

BACKGROUND: Antibiotic-loaded bone cement (ALBC) has been used in serious cases of musculoskeletal tuberculosis, but the type and amount of antibiotic that should be used in ALBC have not been determined. QUESTIONS/PURPOSES: We therefore determined the (1) elution characteristics and (2) antimycobacterial activity of isoniazid- and rifampicin-loaded bone cement. METHODS: A total of 240 elution samples of each of three discs from 40 g bone cement mixed with one of eight dosages: 1 g, 2 g, and 4 g isoniazid, 1 g, 2 g, and 4 g rifampicin, and a combination of 1 + 1 g or 2 + 2 g of isoniazid and rifampicin. The polymerization of rifampicin-loaded bone cement was delayed to mean 122.5 ± 31.1 minutes. We measured the quantity of isoniazid and rifampicin and the antimycobacterial activity on Days 1, 3, 7, 14, and 30. RESULTS: Isoniazid eluted in almost all the samples while rifampicin was detected only on Day 1 with 2 g (0.7 ± 0.4 ug/mL/day), and until Day 14 with 4 g (0.1 ± 0.0 ug/mL/day). Most of the samples containing isoniazid showed antimycobacterial activity while the samples containing rifampicin showed antimycobacterial activity only on Day 1 with 1 g (0.52 ± 0.18 ug/mL), until Day 14 with 2 g (0.03 ± 0.00 ug/mL), and until Day 30 with 4 g (1.84 ± 1.90 ug/mL). CONCLUSION: Rifampicin was unsuitable for ALBC because of its delayed polymerization. Isoniazid eluted and showed antimycobacterial activity for 30 days. CLINICAL RELEVANCE: The data suggest isoniazid could be considered for use in ALBC for musculoskeletal tuberculosis if used with systemic treatment. For preventing resistance and systemic toxicity, a combination with a second-line drug and an in vivo study would be needed.

A randomized prospective study of glove perforation in orthopaedic surgery: is a thick glove more effective?

We compared perforation rates among operative staff who were randomly assigned either thick latex surgical gloves or conventional gloves for use in performing total knee arthroplasty. A total of 1120 gloves were assessed in 70 total knee arthroplasties. Additionally, the degree of tactile sensitivity provided by the gloves was compared using a two-point discrimination (TPD) test. Perforation occurred in 27 surgeries (38.5%) and in 48 gloves (4.29%). Binary logistic regression analysis revealed that the operator was a risk factor for perforation rate (Odds ratio 14.448, P < .0.01) and that the type of glove was not (P = .896). In the TPD test, tactile sensitivity was lower for a thick outer glove than the conventional double glove (P < .001 for each site). Not only did thick surgical gloves lower tactile sensitivity, they also offered no superior protective effect over conventional gloves.

Relationship between distal screws and femoral arteries in closed hip nailing on computed tomography angiography.

BACKGROUND: Iatrogenic vascular injury as a result of closed hip nailing is not common, but is a regularly reported complication after hip fracture surgeries. METHODS: To prevent vascular injury in closed hip nailing by identifying the range of distances and angles between deep and superficial femoral arteries (DFAs and SFAs) and distal screws. PATIENTS AND METHODS: Forty subjects who underwent computed tomography angiographies were included in this study. Imaginary lines marking the distal screws (proximal femoral nail antirotation-II [PFNA-II], 180 and 300 mm; inter-trochanteric/sub-trochanteric nails [ITST], 200 and 300 mm) were drawn on the scout film. On arterial phase images, angles between distal screw lines and those marking DFAs or SFAs, as well as the distance between each artery and far cortex, were measured using the cross-reference capabilities of the picture archiving and communication system. RESULTS: The short nails (PFNA-II 200 mm and ITST 180 mm) were closest to the DFAs, indicating that these nails are most likely to cause injury (PFNA-II 200 mm: 11.2 ± 13.7° anterior and 9.87 ± 5.83 mm; ITST 180 mm: 22.56 ± 15.92° posterior and 9.24 ± 4.74 mm). The short nails were relatively distant from the SFAs, which were located posteriorly to the long nails (PFNA-II 300 mm and ITST 300 mm). CONCLUSIONS: These data indicate that insertion of distal screws into intramedullary nails increases the risk of injury to vascular structures. Surgeons must take care in drilling or inserting screws to ensure the prevention of vascular injury.

Comparison of patellar retention versus resurfacing in LCS mobile-bearing total knee arthroplasty.

PURPOSE: The aim of this retrospective study was to compare clinical outcomes of total knee arthroplasty (TKA) with and without patellar resurfacing using the Low Contact Stress (LCS) mobile-bearing prosthesis in 275 osteoarthritic knees (199 patients) after a minimum of 7 years of follow-up. METHODS: Patients were divided into a patellar retention group (132 knees) and a resurfacing group (143 knees), with median follow-up durations of 7.8 years (range, 7-8.5 years) and 8.5 years (range, 7-10.6 years), respectively. The demographics of the two groups were otherwise matched. The patelloplasty was performed for patellar retention. Patients were evaluated by a blinded, independent observer using Feller's patellar score, the Knee Society score, patient satisfaction, patellar tilt, and lateral displacement. RESULTS: Patellar resurfacing was not superior to retention with respect to any of the measured variables. Eight knees (6.1%) without and 6 (4.2%) with patellar resurfacing had anterior knee pain related to the patellofemoral joint (n.s.). The reoperation rate related to the patellofemoral joint was 0.8% (n = 1) in the retention group compared with 2.8% (n = 4) in the resurfacing group (n.s.). In the 35 patients who underwent bilateral TKA with patellar resurfacing on only one side, there were no significant differences between the two sides in subjective preference, clinical scores, or functional ability. CONCLUSIONS: The clinical and radiographic outcomes of TKA with the LCS mobile-bearing prosthesis showed no significant difference between the two groups after a minimum of 7 years of follow-up. The findings in this study suggest that patellar retention with a patelloplasty may be viable as a routine procedure, even in knees with advanced patellofemoral arthritis, if soft tissue balancing and a patella-friendly prosthetic design are properly used. LEVEL OF EVIDENCE: Therapeutic, retrospective, comparative study, Level III.

Predicting proximal femur rotation by morphological analyses using translucent 3-dimensional computed tomography.

BACKGROUND: Predicting rotation of proximal femur in femur fracture surgeries is important to prevent malrotation. OBJECTIVE: We aimed to prevent malrotation by developing a simple guideline that enables the prediction of proximal femur rotation using translucent 3-dimensional computed tomography (3D CT). DESIGN: Retrospective. SETTING: One tertiary general hospital in the Republic of Korea. PATIENTS: Thirty-six subjects who underwent CT angiographies for vascular evaluation. INTERVENTION: Translucent 3D CT images were created from the CT data. MAIN OUTCOME MEASURE: Morphologic ratios of the great trochanter (GT) and lesser trochanter (LT) with the hip center as a basic point were measured at neutral position and at 5°, 10°, 15°, 20°, 25°, and 30° of internal rotation (IR) and external rotation (ER). The rotation angles at which the GT ratio becomes 0.5 and 0.33 and the rotation angles at which the LT ratio becomes 0.0 and 1.0 were determined to serve as guide angles. RESULTS: Both the proportion of GT and LT compared with proximal femur with hip center as a reference (GT and LT ratio) gradually increased in the shift from IR to ER. At a neutral position, the GT and LT ratios were approximately 0.4 and 0.5, respectively. At 10°-15° of ER, the approximate GT and LT ratios were 0.5 and 1.0, respectively. At 30° of ER, the GT ratio exceeded 0.6, and the LT ratio exceeded 1.0. Between 10° and 15° of IR, the GT ratio decreased to approximately 0.33 and the LT ratio decreased to 0.0, which indicated that the LT was invisible. CONCLUSIONS: We suggested practical values which might be useful as a reference in the operating room practically and hope that our findings would be helpful to prevent malrotation while performing proximal femur or femur shaft surgeries.

Prescription pattern of NSAIDs and the prevalence of NSAID-induced gastrointestinal risk factors of orthopaedic patients in clinical practice in Korea.

This is a cross-sectional observational study undertaken to explore the current prescription pattern of non-steroidal anti-inflammatory drugs (NSAIDs) and the prevalence of NSAID-induced gastrointestinal (GI) risk factors of orthopaedic patients in real clinical practice in Korea. Study cohort included 3,140 orthopaedic outpatients at 131 hospitals and clinics between January 2008 and August 2008. A self-administered questionnaire was completed by each patient and physician. A simplified risk scoring scale (the Standardized Calculator of Risk for Events; SCORE) was used to measure patients' risk for GI complications. The pattern of NSAIDs prescription was identified from medical recordings. Forty-five percent of the patients belonged to high risk or very high risk groups for GI complications. The cyclooxygenase-2 enzyme (COX-2) selective NSAID showed a propensity to be prescribed more commonly for high/very high GI risk groups, but the rate was still as low as 51%. In conclusion, physician's considerate prescription of NSAIDs with well-understanding of each patient's GI risk factors is strongly encouraged in order to maximize cost effectiveness and to prevent serious GI complications in Korea. Other strategic efforts such as medical association-led education programs and application of Korean electronic SCORE system to hospital order communication system (OCS) should also be accompanied in a way to promote physician's attention.

Anterior-posterior glide mobile-bearing total knee arthroplasty: complications related to prosthesis design.

The aim of this study was to evaluate complications related to prosthesis design in patients managed with cemented total knee arthroplasty using anterior-posterior glide mobile-bearing prosthesis. One hundred eighty-three total knee arthroplasties were performed using this prosthesis on 146 patients, with a minimum of 7 years of follow-up. There were late dislocations of the bearing in 2 knees, anterior soft tissue impingements in 6 knees at an earlier follow-up, excessive anteroposterior translation in 5 knees, and a fracture of the femoral component induced by osteolysis in 1 knee. Design modifications in the restraint mechanisms of the anterior-posterior glide mobile-bearing prosthesis may be required to minimize the development of complications with regard to sagittal instability and to improve the prosthesis' longevity.

Straight tapered titanium stem with alumina bearing in cementless primary total hip arthroplasty: a minimum 5-year follow-up.

The aim of this study was to assess the midterm results of primary cementless total hip arthroplasty using a tapered stem and alumina bearing couple in active patients. After a minimum of 5 years of follow-up, 78 arthroplasties in 72 patients were reviewed retrospectively. The mean Harris hip score was 94 points, and 2 hips had thigh pain. All components radiographically demonstrated stable fixation by bone ingrowth and mild stress shielding of the proximal femur were noted in 14% of hips. There was no significant osteolysis or aseptic loosening. There was a ceramic head fracture in 1 hip and audible sounds in 2 hips. The results of total hip arthroplasty with a straight, tapered, proximally porous-coated stem and alumina-on-alumina bearing were encouraging for active patients.

Comparison of simultaneous bilateral and staged bilateral total knee arthroplasty in terms of perioperative complications.

We compared bilateral total knee arthroplasty (TKA) performed at a single session vs those performed at 2 separate sessions with respect to complications, amount of blood loss, and length of hospital stay. Study participants included 119 consecutive patients undergoing simultaneous bilateral TKA and an additional 119 patients undergoing staged bilateral TKA. Systemic complication in the simultaneous bilateral TKA was significantly higher statistically than that in the staged bilateral TKA. Therefore, performing simultaneous bilateral TKA in elderly or high-risk patients results in a significantly higher rate of systemic complications. Simultaneous bilateral TKA is a relatively safe and beneficial procedure with a minimal increase in the risk of systemic complications. However, this procedure should be conducted carefully, particularly in elderly and high-risk patients.

Being Underweight Is Associated with Worse Surgical Outcomes of Total Knee Arthroplasty Compared to Normal Body Mass Index in Elderly Patients.

PURPOSE: Being underweight has never been studied in relation to the radiologic and clinical outcomes of total knee arthroplasty (TKA) in elderly patients. The aim of this study was to determine the effect of being underweight on TKA radiological and clinical outcomes and to investigate whether being underweight influences postoperative complications compared to normal body mass index (BMI) in elderly patients. PATIENTS AND METHODS: A total of 118 female patients aged 65 years or older with BMI < 25 kg/m2 who underwent primary TKA were divided into two groups based on BMI: group A: 18.5 kg/m2 < BMI < 25 kg/m2; group B: BMI < 18.5 kg/m2. The radiologic and clinical outcomes were evaluated at follow-up of 6, 12, and 24 months after surgery such as the hip-knee-ankle angle, the American Knee Society (AKS) score, Western Ontario and McMaster University score (WOMAC), and patellofemoral (PF) scale. Moreover, postoperative complications during follow-up were investigated. RESULTS: Preoperative clinical scores did not differ significantly between the two groups. Postoperative WOMAC pain (1.8 ± 1.9 versus 3.4 ± 2.6, p = 0.02), WOMAC function (12.4 ± 8.1 versus 16.5 ± 8.5, p = 0.012) and PF scales (26.1 ± 3.6 versus 23.7 ± 4.1, p = 0.002) were worse in the underweight group at 12 and 24 months after surgery. The frequency of postoperative complications did not differ significantly between groups. In multivariate linear regression analysis, underweight patient group was significantly associated with worse postoperative WOMAC and PF scores (p = 0.002, 0.005). CONCLUSION: Although postoperative complications of TKA did not differ between groups, underweight patients had worse clinical outcomes of TKA compared to patients with normal BMI in elderly patients. Therefore, care should be taken when performing TKA in elderly underweight patients.

Femoral component fracture due to osteolysis after cemented mobile-bearing total knee arthroplasty.

A 58-year-old man with osteoarthritis in the left knee underwent a total knee arthroplasty with a New Jersey anterior-posterior gliding low contact stress mobile-bearing implant. All femoral, tibial, and patellar components were implanted with bone cement. Pain developed at 43 months postsurgery, and plain radiography revealed a vertical crack in the femoral component and osteolysis at the medial femoral condyle. The femoral and tibial components were revised, and the bone defect at the medial femoral condyle was reconstructed using an allogeneic strut bone graft. Microscope examination identified polyethylene particles with foreign body granulomatous reaction, and scanning electron microscopy revealed fatigue failure of the femoral component. Osteolysis due to polyethylene particles can lead to fracture of the femoral component after cemented anterior-posterior gliding low contact stress mobile-bearing total knee arthroplasty.

Robot-assisted unicompartmental knee arthroplasty can reduce radiologic outliers compared to conventional techniques.

BACKGROUND: The aim of this study was to compare the clinical and radiologic outcomes of robot-assisted unicompartmental knee arthroplasty (UKA) to those of conventional UKA in Asian patients. METHODS: Fifty-five patients underwent robot-assisted UKA and 57 patients underwent conventional UKA were assessed in this study. Preoperative and postoperative range of motion (ROM), American Knee Society (AKS) score, Western Ontario McMaster University Osteoarthritis Index scale score (WOMAC), and patellofemoral (PF) score values were compared between the two groups. The mechanical femorotibial angle (mFTA) and Kennedy zone were also measured. Coronal alignments of the femoral and tibial components and posterior slopes of the tibial component were compared. Additionally, polyethylene (PE) liner thicknesses were compared. RESULTS: There was no significant difference between the two groups regarding postoperative ROM, AKS, WOMAC and PF score. Robot group showed fewer radiologic outliers in terms of mFTA and coronal alignment of tibial and femoral components (p = 0.022, 0.037, 0.003). The two groups showed significantly different PE liner thicknesses (8.4 ± 0.8 versus 8.8 ± 0.9, p = 0.035). Robot group was the only influencing factor for reducing radiologic outlier (postoperative mFTA) in multivariate model (odds ratio: 2.833, p = 0.037). CONCLUSION: In this study, robot-assisted UKA had many advantages over conventional UKA, such as its ability to achieve precise implant insertion and reduce radiologic outliers. Although the clinical outcomes of robot-assisted UKA over a short-term follow-up period were not significantly different compared to those of conventional UKA, longer follow-up period is needed to determine whether the improved radiologic accuracy of the components in robotic-assisted UKA will lead to better clinical outcomes and improved long-term survival.

Factors affecting outcome after total knee arthroplasty in patients with diabetes mellitus.

PURPOSE: To compare the clinical outcome and complications following total knee arthroplasty (TKA) in diabetic and non-diabetic patients, and to identify diabetes-related risk factors for negative outcomes. MATERIALS AND METHODS: 222 primary TKAs in patients with diabetes were evaluated using Knee Society scores and Hospital for Special Surgery score. Postoperative complications were reviewed retrospectively. The mean follow-up was 53.2 months. The effect of diabetes-related factors and comparison with a matched control group were analyzed statistically. RESULTS: Significant improvements were noted in all the scores after TKA (p < 0.05). There was no statistical difference in clinical sores between the diabetic and non-diabetic patients. In multivariate analysis associating age, gender and body mass index with pain and knee score at the latest follow-up, the average knee scores in normal and overweight group were found to be significantly higher than those in the obese group. The diabetic patients had an increased overall incidence of postoperative complications (17.6%) compared with the control group (8.1%) (p < 0.05). Particularly, the rate of wound complications such as skin necrosis, bulla formation or erythema with drainage was higher in the diabetic group (p < 0.05). Diabetes-related factors did not influence the incidence of complications. Associated diseases were the only significant risk factors correlated with wound complications and meniscal bearing dislodgement. CONCLUSION: Patients with diabetes can benefit from TKA, even though diabetic patients are at an increased risk for overall postoperative and wound complications. Preoperative factors such as obesity and associated diseases may adversely affect the clinical outcome of TKA in diabetic patients.

[Effects of different low limits of irrigation on nutrients, enzyme activity and glomalin-rela-ted soil protein in soil aggregates of drip irrigation under plastic film.] / è†œä¸‹æ»´çŒä¸åŒçŒæ°´æŽ§åˆ¶ä¸‹é™å¯¹è®¾æ–½åœŸå£¤å›¢èšä½“å »åˆ†ã€é ¶æ´»æ€§å’Œçƒå›Šéœ‰ç´ å«é‡çš„å½±å“.

Irrigation is the main source of soil water in greenhouse. There is a lack of understanding on the effects of drip irrigation under the plastic film on the distribution characteristics of soil nutrients, enzyme activity and glomalin-related soil protein (GRSP) in soil aggregates. The effects of different irrigation low limits (20 kPa, D20; 30 kPa, D30; 40 kPa, D40) on soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), urease activity, invertase activity and GRSP in soil aggregates were investigated under the greenhouse with the continuously six years' irrigation. The results showed that compared with D20 and D40 treatments, D30 treatment significantly decreased the proportion of micro-aggregate (<0.25 mm), increased the proportion of macro-aggregate (>0.25 mm), and improved the mean mass diameter (MWD) by 26.4% and 13.4%, respectively. The concentrations of SOC, TN, TP and GRSP were relatively higher in 2-1 mm, 1-0.25 mm, and <0.053 mm aggregates. About 46.5% of SOC, 53.3% of TN and 37.7% of TP were distributed in the 1-0.25 mm aggregates. The urease and invertase activities were increased with the decreases in the size of aggregates, which were significantly increased in D30 and D40 treatments. The 1-0.25 mm aggregates had highest contributions to enzyme activities, with 38.7% of urease and 41.2% of invertase in bulk soil. Results from the correlation analysis showed that MWD was highly positively correlated with GRSP, SOC and urease activity, and the concentration of GRSP was highly positively correlated with SOC and urease activity. Therefore, the irrigation low limits of 30 kPa promoted soil aggregate stability and protection of soil aggregates to nutrients, enzyme activities and GRSP in greenhouse.

Intra-synovial ropivacaine and morphine for pain relief after total knee arthroplasty: a prospective, randomized, double blind study.

PURPOSE: Several analgesic techniques are available for pain management after a major operation. MATERIALS AND METHODS: From December 2005 to February 2006, a prospective, double-blind study was performed involving 90 patients who had undergone a total knee arthroplasty. Patients were randomly divided into three equal groups (n=30). Demographic data, including age, height, weight, knee score, visual analogue scale (VAS), and range of flexion were evaluated preoperatively. Before wound closure, patients were given intra-synovial injections of the following solutions: patients in group I received 40mL of 300mg ropivacaine with 1:200,000 epinephrine and 5mg morphine; patients in Group II received 40mL of 300mg ropivacaine with epinephrine; and patients in Group III received 50mL normal saline as a control. All patients received an epidural patient-controlled analgesia (PCA) for 24 postoperative hours. Analgesic efficacy was evaluated using the VAS at intervals of 2, 4, 6, 12, 24, 32, 40, and 48 hours postoperatively. During this period, the side effects, the dosage of rescue analgesia required, and the range of knee flexion were recorded for each group. RESULTS: There were no significant differences among the three groups with regards to the VAS and the required dose of rescue analgesia (p > 0.05). None of the groups demonstrated significant differences in the range of knee flexion and the incidence of postoperative nausea and emesis (p > 0.05). CONCLUSION: Therefore, we found that ropivacaine, alone or with morphine, injected into the synovial tissue, along with an epidural PCA has no additional benefits in pain control after a total knee arthroplasty.

Extramedullary Tibial Bone Cutting Using Medial Cortical Line in Total Knee Arthroplasty.

Purpose: This study aims to identify the effectiveness of the medial cortical line for attaining a more accurate tibial component alignment in proximal tibial resection using an extramedullary alignment rod. Materials and Methods: The study examined 100 cases of total knee arthroplasty performed from December 2013 to February 2014 in a retrospective manner. On a preoperative anteroposterior (AP) radiograph of the entire tibia, we identified the medial cortical line that runs parallel to the tibial anatomical axis and passes the medial tibial spine, and measured the point where the medial cortical line crosses between the medial malleolus and the lateral malleolus in the ankle joint. Results: The preoperative AP radiograph of the tibia showed the medial cortical line passing the point 40.4%±0.8% medial to the distance from the medial malleolus to the lateral malleolus including the skin thickness in the ankle joint. When the proximal tibial resection was performed with the extramedullary tibial cutting guide aligned with the medial cortical line, the tibial component angle averaged 0.7°±0.3° varus and the alignment accuracy of the tibial component within 0°±3° varus amounted to 97.0%. Conclusions: The use of the medial cortical line in proximal tibial resection with an extramedullary tibial cutting guide allowed for relatively accurate alignment of the tibial component.