Influence of strength and balance ability on functional performance in the involved and uninvolved sides after anterior cruciate ligament reconstruction

BACKGROUND

The restoration and management of the uninvolved side have been emphasized to prevent a second anterior cruciate ligament (ACL) injury and to ensure that athletes return to sports after ACL reconstruction.

OBJECTIVE

To determine the factors influencing the single leg hop test (SLHT) and single leg vertical jump test (SLVJT) at 1 year postoperatively after ACL reconstruction in both the involved and uninvolved sides.

METHODS

Ninety-four patients who underwent ACL reconstruction were assessed at 1 year postoperatively. Multiple regression models included eight independent variables with two dependent variables (SLHT and SLVJT.), each on the involved and uninvolved side.

RESULTS

On the involved side, the Y balance test (YBT), extensor peak torque per body weight (PT/BW), Biodex balance system anteroposterior index (BBS-API), and sex accounted for 53.9% of the variance in SLHT (P= 0.002), and extensor PT/BW and YBT accounted for 26.3% of the variance in SLVJT (P= 0.027). On the uninvolved side, YBT, sex, age, BBS-API, and flexor PT/BW accounted for 47.0% of the variance in SLHT (P= 0.046), and flexor PT/BW, YBT, and age accounted for 44.9% of the variance in SLVJT (P= 0.002).

CONCLUSION

Knee extensor strength on the involved side and flexor strength on the uninvolved side influence the two functional performance tests. The YBT was an important factor in the two functional performance tests in both sides. Anteroposterior stability was the only factor that influenced the SLHT bilaterally.

Rehabilitation after Repair of Medial Meniscus Posterior Root Tears: A Systematic Review of the Literature

Background

There is no consensus established on postoperative rehabilitation after medial meniscus posterior root tear (MMPRT) repair, including when and how physicians can apply range of motion (ROM) exercise, weight-bearing (WB), brace use, and return to sports (RTS). The purpose of this study was to systematically review the literature on postoperative rehabilitation characteristics of MMPRT repair regarding ROM, WB, brace use, and RTS.

Methods

A literature search was performed using the Medline/PubMed, Cochrane Central Register of Controlled Trials, and Embase databases. The inclusion criteria were English language, human clinical studies, and studies describing rehabilitation protocols after MMPRT repair such as ROM, WB, brace use, and RTS. Abstracts, case reports, cohort studies, controlled laboratory studies, human cadaveric or animal studies, systematic reviews, and meta-analyses were excluded.

Results

Thirteen studies were included. Of the 12 ROM studies, ROM was started immediately within 1 or 2 days after operation in 6 studies and after 2 to 3 weeks of knee immobilization in the rest. Of the 13 WB studies, partial weight-bearing was initiated 1 to 4 weeks after operation in 8 studies and 6 weeks in the rest. Of the 9 brace studies, patients were immobilized by a splint for 2 weeks in 3 studies, and in the rest, a brace with full extension was applied for 3 to 6 weeks after several days of splint application. Of the 7 RTS studies, RTS was allowed at 6 months in 6 studies and 5 to 7 months in 1 study.

Conclusions

This systematic review revealed conservative rehabilitation protocols were more widely adapted as ROM and WB were restricted at certain degrees during postoperative periods in most protocols analyzed. However, it is impossible to identify a consensus on rehabilitation protocols as the protocols analyzed in this review were distinct each other and heterogeneous. In the future, a well-designed comparative study among different rehabilitation protocols is essential to establish a consensus.

Changes in Bone Marrow Lesions Following Root Repair Surgery Using Modified Mason–Allen Stitches in Medial Meniscus Posterior Root Tears

Background and Objectives: Root repair can prevent osteoarthritis (OA) by restoring hoop tension in medial meniscus posterior root tears (MMPRTs). This study aims to investigate bone marrow edema (BME) lesions known to be associated with OA following MMPRTs. Methods: Thirty patients with transtibial pull-out repair were recruited. Subchondral BME lesions were evaluated using magnetic resonance imaging (MRI) at 1-year follow-ups. Participants were categorized into three groups: no change of BME lesions (group one), improved BME lesions (group two) and worsened BME lesions (group three). Clinical scores and radiological outcomes, specifically Kellgren–Lawrence grade, medial joint space width and cartilage grade and meniscal extrusion were evaluated and compared between groups. Results: After surgery, twenty-three patients with no BME, three patients with BME lesions on the medial femoral condyle, one patient with BME lesions on the medial tibia plateau and three patients with BME lesions on both were investigated. A total of 20 patients in group one (66.7%) showed no change in BME lesions. In group two, seven patients (23.3%) presented with improved BME lesions. Only three patients (10%) showed worsened BME lesions (group three). Moreover, Lysholm scores and the rate of progression of cartilage grades were significantly worse in group three patients. Meniscal extrusion was significantly reduced in group two, whereas extrusion was significantly progressed in group three. Conclusions: Patients with worsened BME lesions showed less favorable outcomes than other patients. A decrease in meniscal extrusion can have a positive effect on BME lesions after root repair.

Correlation Between Y-Balance Test and Balance, Functional Performance, and Outcome Measures in Patients Following ACL Reconstruction

BACKGROUND

The Y-Balance test (YBT) is commonly used to evaluate balance after anterior cruciate ligament reconstruction (ACLR). However, several studies have also used it as a functional performance test (FPT).

PURPOSE

This study aimed to examine the relationship between YBT scores and measures of knee joint laxity, static balance, knee flexor and extensor torque and strength ratio, and FPTs.

STUDY DESIGN

Retrospective cohort study.

METHODS

Fifty-nine patients who underwent ACLR using hamstring autografts were retrospectively analyzed. The Pearson correlation coefficient was used to determine the strength of the association between scores on the YBT and selected outcomes including laxity measured via the KT-2000 arthrometer, static balance measured via the Biodex Balance System, isokinetic muscle torque and hamstring-to-quadriceps (HQ) ratio, and performance on the single leg hop test and the single leg vertical jump test.

RESULTS

Forty-six men and 13 women were included. The mean age and follow-up period were 29.6 ± 9.6 years and 12.4 ± 2.1 months, respectively. The KT-2000 arthrometer measures, Biodex Balance System scores, and HQ ratio measurements were not significantly correlated with the YBT scores. All YBT scores, except the YBT-anterior score, correlated with the isokinetic extensor and flexor torques (r-values: 0.271-0.520). All the YBT scores had significant weak to moderate correlations with the single leg hop test and single leg vertical jump test scores: YBT-anterior (r = 0.303, r = 0.258), YBT-posteromedial (r = 0.475, r = 0.412), YBT-posterolateral (r = 0.525, r = 0.377), and YBT-composite (r = 0.520, r = 0.412).

CONCLUSION

Post-ACLR YBT scores correlated with functional performance and muscle strength, but not with static balance, joint laxity, and HQ ratios. The YBT scores as a measure of balance are related to improved functional performance and isokinetic torque measures.

LEVEL OF EVIDENCE

3.

An increasing trend of posterior cruciate ligament reconstruction in South Korea: epidemiologic analysis using Korean National Health Insurance System Database

Background

The posterior cruciate ligament is crucial for posterior stability of the knee joint, and, as well as anterior cruciate ligament reconstruction, posterior cruciate ligament reconstruction (PCLR) has attracted interest in orthopedic literature. A few studies have investigated epidemiologic data of PCLR in Western countries. However, there has been no report on the epidemiological pattern of PCLR in the Asian population, including South Korea. Therefore, this study investigated the incidence and trends of PCLR in South Korea using the Korean National Health Insurance (NHI) System Database.

Methods

The data was collected by the Korean Health Insurance Review and Assessment Service (HIRA) from 2008 to 2016 in South Korea. Patients with a record of cruciate ligament reconstruction and PCLR were allocated from the database. An analysis of the total number and incidence per 100,000 people/year of PCLR procedures and other epidemiologic parameters was conducted according to sex and age.

Results

The incidence of PCLR procedures rose from 2.3 to 2.6 per 100,000 people (from 1101 to 1299 total cases; 13% increase) between 2008 and 2016: from 3.8 to 4.0 (from 901 to 1000) in males, and from 0.8 to 1.2 (from 200 to 299) in females. PCLR was performed more frequently in males than in females, however, the rate of increase was higher in females than males. The incidence of PCLR over 9  years was highest in patients in their 20s, followed by patients in their 40s and 30s.

Conclusion

The incidence of PCLR procedures increased by 13% over 9 years in South Korea. PCLR was performed approximately three times more in men than in women. The incidence of PCLR was highest in patients in their 20s, followed by those in their 40s. The current study will enhance our understanding of the epidemiology of PCLR.

Study design

Descriptive Epidemiology Study.

Preoperative varus alignment and postoperative meniscus extrusion are the main long-term predictive factors of clinical failure of meniscal root repair

PURPOSE

No studies have been conducted to determine long-term predictors of clinical failure after surgical root repair. This study identified long-term prognostic factors of clinical failure after pull-out repair of medial meniscus posterior root tears (MMPRTs) at a minimum of 10 year follow-up.

METHODS

A total of 37 patients who underwent MMPRT pull-out repair and had been observed for more than 10 years were recruited for this study. The mean follow-up period was 125.9 ± 21.2 months. Clinical failure of the procedures was defined as conversion to total knee arthroplasty (TKA). Participants were categorized into two groups: non-failure and failure groups. Various factors, including demographic features and radiologic findings, were analyzed and compared between the two groups. Meniscus extrusion was assessed at coronal magnetic resonance imaging preoperatively and 1 year postoperatively. Independent risk factors were determined by univariate analysis and logistic regression analysis. To determine the cut-off value for risk factors, the receiver-operating characteristic curve analysis was performed.

RESULTS

In total, eight patients (22%) were converted to TKA during the follow-up period. With univariate analysis, statistically significant differences between two groups were observed in mechanical varus alignment (P = 0.018), rate of the number of patient with more meniscal extrusion values after surgery (P = 0.024), and the difference between the preoperative and 1-year postoperative value of meniscus extrusion (mm) (P = 0.010). In a logistic analysis, OR of mechanical varus alignment and differences in meniscus extrusion value before and 1 year after surgery was 1.5 (P = 0.048) and 3.7 (P = 0.034). The cut-off values of mechanical varus alignment and differences in meniscus extrusion values were 5 degrees and 0.7 mm.

CONCLUSION

Clinically, preoperative varus alignment and increased meniscal extrusion after surgery were found to be predictive for a clinical failure after meniscal root repair in a long-term perspective. Thus, these negative prognostic factors should be taken into consideration for performing root repair in MMPRTs.

LEVEL OF EVIDENCE

Level III.

An increasing trend of the number of meniscus allograft transplantation in Korea

PURPOSE

Meniscus allograft transplantation (MAT) can be performed to treat symptomatic patients with meniscus-deficient knees. However, the current epidemiologic status of MAT is unknown in many countries, including Korea. This study aimed to investigate the national trends of MAT in Korea which covers MAT procedures by the Korean national health insurance system.

METHODS

Information from the national database was acquired through the Korean Health Insurance Review and Assessment Service (HIRA) from 2010 to 2017. All patients encoded as MAT were included. The total number of MATs and their incidence per 100,000 persons were determined, and the results were stratified by age and sex.

RESULTS

The total number of MATs and their incidence per 100,000 persons per year were 369 and 0.77, respectively, in 2010, which increased to 826 and 1.72, respectively, in 2017. The number of MATs increased by 124% over 8 years. The peaks for the total number of MATs and their incidence were seen in patients in their 20 s in 2010, but in 2017, the peaks were observed in patients who were in their 40 s. MAT was performed more frequently in males (61%) than in females (39%) over the study period.

CONCLUSION

The total number of MATs and their incidence had increased by 124% between 2010 and 2017. The peak treatment age range for MAT changed from 20 years of age in 2010 to 40 years of age in 2017, and MAT was performed more frequently in males than in females.

LEVEL OF EVIDENCE

IV.

Efficacy of GCWB106 (Chrysanthemum zawadskii var. latilobum extract) in osteoarthritis of the knee: A 12-week randomized, double-blind, placebo-controlled study

BACKGROUND

GreenCross Wellbeing Corporation (GCWB) 106 is a food item based on Chrysanthemum zawadskii var. latilobum extract. It has an inhibitory effect on joint inflammation.

OBJECTIVE

This study investigated the efficacy and safety of GCWB106 for osteoarthritis (OA) of the knee joint.

METHODS

Overall, 121 participants with mild OA were recruited and randomly divided into two groups. One group received GCWB106 for 12 weeks and the other group received placebo for 12 weeks. Outcomes were evaluated using the Korean-Western Ontario and McMaster Universities Index (K-WOMAC), visual analog scale, Korean Short Form Health Survey 36 score, and laboratory test results.

RESULTS

After 12 weeks of study treatment, the GCWB106 group exhibited a significant improvement compared with the placebo group in overall K-WOMAC score (P = .042) and K-WOMAC physical function score (P = .015). The GCWB106 group showed significant improvement in the visual analog scale pain score (P < .001) compared with the placebo group after 6 weeks and 12 weeks; no adverse drug reactions or serious adverse events were reported in either group.

CONCLUSION

GCWB106 can safely reduce pain and improve knee function with therapeutic effects in OA of the knee joint.

LEVEL OF EVIDENCE

Randomized, double-blind, placebo-controlled clinical study, Level I.

Root Repair Versus Partial Meniscectomy for Medial Meniscus Posterior Root Tears: Comparison of Long-term Survivorship and Clinical Outcomes at Minimum 10-Year Follow-up

BACKGROUND

The importance of repair in medial meniscus posterior root tears (MMPRTs) has been increasingly recognized because it restores hoop tension. However, no study has compared the long-term outcomes between meniscectomy and repair.

HYPOTHESIS

Survivorship and clinical outcomes of repair would be better than those of meniscectomy after long-term follow-up.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Between 2005 and 2009, patients with MMPRTs who had been followed up for at least 10 years after partial meniscectomy (n = 18) or pullout repair (n = 37) were recruited. Clinical assessments, including the Lysholm score and International Knee Documentation Committee (IKDC) subjective score, were evaluated preoperatively and at the final follow-up. The final results in each group were compared with the preoperative results, and the final results of the groups were compared. Clinical failure was defined as conversion to total knee arthroplasty (TKA), and the final clinical scores were assessed just before TKA. Kaplan-Meier survival analysis was used to investigate the survival rates of surgical procedures.

RESULTS

Mean ± SD follow-up period was 101.4 ± 45.9 and 125.9 ± 21.2 months in the meniscectomy and repair groups, respectively (P = .140). The mean Lysholm and IKDC scores, respectively, in the meniscectomy group were 50.8 ± 7.7 and 37.6 ± 7.0 preoperatively and 58.2 ± 22.1 and 44.4 ± 19.0 postoperatively (P = .124; P = .240). In the repair group, the mean Lysholm score and IKDC score, respectively, significantly increased from 52.3 ± 10.9 and 41.0 ± 9.6 preoperatively to 77.1 ± 24.0 and 63.7 ± 20.6 postoperatively (P < .001; P < .001). The final Lysholm and IKDC scores in the repair group were significantly better than those in the meniscectomy group (P = .004; P = .003). In cases of clinical failure, 10 patients (56%) in the meniscectomy group and 8 patients (22%) in the repair group converted to TKA in the follow-up period (P = .016). According to Kaplan-Meier analysis, the 10-year survival rates for the meniscectomy and repair groups were 44.4% and 79.6%, respectively (P = .004).

CONCLUSION

In MMPRTs, root repair was superior to partial meniscectomy in terms of clinical results for at least 10 years of follow-up. From a long-term perspective, repair with restoration of hoop tension is more effective management than meniscectomy.

National Trends of Meniscectomy and Meniscus Repair in Korea

BACKGROUND

Meniscus surgeries are frequently performed in orthopaedics. However, their current status is not well known in many countries, including Korea. This study aimed to investigate the national trends of meniscus surgery in Korea.

METHODS

Information from the national database was acquired through the Korean Health Insurance Review and Assessment Service from 2010 to 2017. All cases coded as meniscectomy or meniscus repair were included. The total number and incidence of cases of meniscus surgery per 100,000 persons were determined, and the results were stratified by age and gender. The meniscus repair ratio for the total number of meniscus surgeries was evaluated.

RESULTS

The total number and incidence of meniscectomy cases were 65,752 and 137, respectively, in 2010, which increased to 74,088 and 154, respectively, in 2017. The number of meniscectomies increased by 12.67% in 8 years. The total number and incidence of meniscus repair cases were 9,055 and 18, respectively, in 2010, which increased to 14,947 and 31 in 2017. The number of meniscus repairs increased by 65.04%. The meniscus repair ratio was 12.1% in 2010, which increased to 16.8% in 2017. The highest peak was noted for patients who underwent meniscus surgeries in their 50s and 60s. Meniscectomy was performed more frequently in women (57%) than in men (43%), whereas repair was performed more frequently in men (54%) than in women (46%) over the study period.

CONCLUSION

The total number and incidence of meniscus surgeries increased from 2010 to 2017; the number and incidence of meniscus repair procedures increased more rapidly than those of meniscectomy, with the peak treatment age for both surgeries being in the 50s and 60s. The current study will contribute to understanding the epidemiology of meniscus surgery, its prevention, and cost-saving measures in Korea.

The International Knee Documentation Committee Score Indicates Midterm Patient Satisfaction with Outcomes after Meniscal Allograft Transplantation

BACKGROUND

This study aimed to identify the factors associated with patient satisfaction with the outcome of meniscal allograft transplantation (MAT).

MATERIALS AND METHODS

Patients treated with MAT from March 2006 to May 2009 were asked to complete a five-point Likert scale regarding satisfaction with the outcome of MAT, in addition to the following subjective outcome evaluation forms: the International Knee Documentation Committee (IKDC) subjective forms, Knee Society Score knee and function forms, and Lysholm Knee Scoring Scale. We collected radiologic data using X-ray and magnetic resonance imaging and assessed isokinetic muscle strength test using the Biodex System 3. We investigated whether these parameters were significantly associated with patient satisfaction. Statistical analysis was computed using univariate and multivariable logistic regression.

RESULTS

Among the 130 patients who underwent MAT, 49 participated in the interview and were included in this study. The mean followup period was 50.4 months. Mean patient age was 40 (±9) years; 33 were male and 16 were female (33%). The lateral meniscus was transplanted in 13 (27%) patients, while the medial meniscus was involved in 36 (73%) patients. On univariate analysis, sex and isokinetic extension strength deficit at 60° and 180° as well as the IKDC, Knee Society, and Lysholm scores showed significant association with patient satisfaction regarding the outcome. On multivariable logistic regression, only the IKDC score showed a significant association, with P = 0.04.

CONCLUSIONS

The study results support the importance of patient-reported subjective outcomes in terms of patient satisfaction following a surgical procedure. Regarding MAT, the IKDC outcome score reflects patient satisfaction.

LEVEL OF EVIDENCE

Level III.

Pullout fixation for medial meniscus posterior root tears: clinical results were not age-dependent, but osteoarthritis progressed

PURPOSE

This study investigated the outcomes of pullout fixation for medial meniscus posterior root tears (MMPRTs) in patients ≤ 60 years old versus patients > 60 years old. It was hypothesized that older patients would demonstrate results comparable with those of younger patients.

METHODS

Patients with pullout fixation who were followed-up for more than 5 years were included. Patients were categorized into two groups based on age (group A, ≤ 60 years; group B, > 60 years). The Lysholm score, Kellgren-Lawrence (K-L, 0/1/2/3/4) grade, and medial joint space width were evaluated retrospectively. Preoperative results were compared with the final results in each group, which were compared between groups.

RESULTS

Twenty-five patients in group A (mean age, 54.7 ± 3.8 years) and 22 patients in group B (mean age, 65.6 ± 4.4 years) were recruited. The mean follow-up duration was 70.9 months. The Lysholm score (group A, 53.0 ± 9.1 to 86.0 ± 12.1, P < 0.001; group B, 51.1 ± 7.1 to 82.9 ± 9.7, P < 0.001) improved significantly. However, the joint space width (group A, 4.7 ± 1.1 to 3.9 ± 1.1 mm, P < 0.001; group B, 4.7 ± 0.9 to 3.8 ± 0.9 mm, P < 0.001) and K-L grade (group A, 3/17/5/0/0 to 0/7/11/7/0, P < 0.001; group B, 2/14/6/0/0 to 0/3/14/5/0, P < 0.001) worsened significantly. No significant differences between groups were observed in final outcomes, including Lysholm score (n.s.), K-L grade (n.s.), and joint space narrowing (n.s.). No case with operation failure that require total knee arthroplasty was not observed.

CONCLUSION

MMPRT fixation did not prevent the progression of arthrosis completely. However, clinical outcomes were not age-dependent. Thus, age may not be a critical factor to consider when applying fixation.

LEVEL OF EVIDENCE

Retrospective case-control study; Level of evidence, IV.

Rivaroxaban and Acetylsalicylic Acid for Prevention of Venous Thromboembolism Following Total Knee Arthroplasty in Korean Patients

Purpose

To investigate the incidence of venous thromboembolism (VTE) after total knee arthroplasty (TKA) with chemoprophylaxis using acetylsalicylic acid (AA) or rivaroxaban in Korean patients.

Materials and Methods

Between May 2011 and November 2013, 268 TKA patients (330 cases) were randomly allocated to 3 groups (group A: subcutaneous injection of 5,000 IU low-molecular-weight heparin for 2 days followed by oral administration of 100 mg AA for 5 days; group X7: oral administration of 10mg rivaroxaban for 7 days; and group X10: oral administration of 10 mg rivaroxaban for 10 days). Multidetector-row computed tomography (MDCT) was performed at 10 days and 3 months postoperatively to evaluate VTE changes.

Results

The VTE incidence was 38.2%, 20.0%, and 10.0% in groups A, X7, and X10, respectively (p<0.001). Pulmonary embolism (PE) was identified in 19.1%, 10.0%, and 2.7% in groups A, X7, and X10, respectively (p<0.001). Proximal or symptomatic deep vein thrombosis (DVT) occurred primarily in group A, but the incidence was not significantly different among groups. On follow-up MDCT, PE was resolved completely with treatment in 29/30 (96.7%), and so was asymptomatic distal DVT in 24/27 (88.8%) without treatment.

Conclusions

Rivaroxaban had a lower incidence of overall VTE than AA, but no difference was observed in symptomatic VTE. The 10-day course of rivaroxaban had a lower incidence of overall VTE than the 7-day course.

Comparison of Tibiofemoral Contact Mechanics After Various Transtibial and All-Inside Fixation Techniques for Medial Meniscus Posterior Root Radial Tears in a Porcine Model

PURPOSE

To compare tibiofemoral contact mechanics after fixation for medial meniscus posterior root radial tears (MMPRTs).

METHODS

Seven fresh knees from mature pigs were used. Each knee was tested under 5 conditions: normal knee, MMPRT, pullout fixation with simple sutures, fixation with modified Mason-Allen sutures, and all-inside fixation using Fastfix 360. The peak contact pressure and contact surface area were evaluated using a capacitive sensor positioned between the meniscus and tibial plateau, under a 1,000-N compression force, at different flexion angles (0°, 30°, 60°, and 90°).

RESULTS

The peak contact pressure was significantly higher in MMPRTs than in normal knees (P = .018). Although the peak contact pressure decreased significantly after fixation at all flexion angles (P = .031), it never recovered to the values noted in the normal meniscus. No difference was observed among fixation groups (P = .054). The contact surface area was significantly lower in MMPRTs than in the normal meniscus (P = .018) and increased significantly after fixation at all flexion angles (P = .018) but did not recover to within normal limits. For all flexion angles except 60°, the contact surface area was significantly higher for fixation with Mason-Allen sutures than for fixation with simple sutures or all-inside fixation (P = .027). At 90° of flexion, the contact surface area was significantly better for fixation with simple sutures than for all-inside fixation (P = .031).

CONCLUSIONS

The peak contact pressure and contact surface area improved significantly after fixation, regardless of the fixation method, but did not recover to the levels noted in the normal meniscus after any type of fixation. Among the fixation methods evaluated in this time 0 study, fixation using modified Mason-Allen sutures provided a superior contact surface area compared with that noted after fixation using simple sutures or all-inside fixation, except at 60° of flexion. However, this study had insufficient power to accurately detect the differences between the outcomes of various fixation methods.

CLINICAL RELEVANCE

Our results in a porcine model suggest that fixation can restore tibiofemoral contact mechanics in MMPRT and that fixation with a locking mechanism leads to superior biomechanical properties.

Effects of salmon DNA fraction in vitro and in a monosodium iodoacetate-induced osteoarthritis rat model

PRF001 is a fragmented DNA polymer extracted from the testes of salmon. The purpose of this study was to assess the anti-inflammatory effect of PRF001 in vitro as well as the protective effect of PRF001 intake against arthritis in a rat model. In vitro, cell survival and inflammatory markers after H₂O₂ treatment to induce cell damage were investigated in CHON-001 cells treated with different concentrations of PRF001. In vivo, osteoarthritis was induced by intra-articular injection of monosodium iodoacetate (MIA) into the knee joints of rats. After consumption of PRF001 (10, 50, or 100 mg/kg) for 4 weeks, inflammatory mediators and cytokines in articular cartilage were investigated. In vitro, the levels of inflammatory markers, IL-1β, TNF-α, COX-2, iNOS, and PGE2, were significantly suppressed by PRF001 treatment. In vivo, the inflammatory mediators and cytokines, IL-1β, p-Erk1/2, NF-κB, TNF-α, COX-2, and PGE2, as well as MMP3 and MMP7, which have catabolic activity in chondrocytes, were decreased in the MIA-induced osteoarthritic rats following intake of PRF001. Histological analysis revealed that PRF001 had a protective effect on the articular cartilage. Altogether, these results demonstrated that the anti-inflammatory property of PRF001 contributes to its protective effects in osteoarthritis through deregulating IL-1β, TNF-α, and subsequent signals, such as p-Erk1/2, NF-κB, COX-2, PGE2, and MMPs.

Survivorship Analysis and Clinical Outcomes of Transtibial Pullout Repair for Medial Meniscus Posterior Root Tears: A 5- to 10-Year Follow-up Study

PURPOSE

This study investigated the clinical outcomes and mid- to long-term survival rates in patients undergoing transtibial pullout repair of medial meniscus posterior root tears (MMPRTs) after a minimum follow-up of 5 years.

METHODS

Between 2005 and 2011, patients with MMPRTs who had been followed for at least 5 years after undergoing transtibial pullout repair were recruited. Participants were identified using medical records and information in a prospectively collected database. Clinical outcomes were assessed based on a comparison of patient preoperative Lysholm scores and their scores at the final follow-up. A Kaplan-Meier survival analysis was used to investigate the survival rates of repair procedures. Clinical failures were defined as cases requiring conversion to total knee arthroplasty (TKA) or having final Lysholm score <65 or less than their preoperative scores.

RESULTS

Overall, 91 patients (mean age, 58.7 ± 9.7 years) were included: the mean follow-up duration was 84.8 ± 13.8 months. Among these patients, the mean Lysholm score improved significantly from 51.8 ± 7.9 preoperatively to 83.0 ± 11.1 at the final follow-up (P < .001). Overall, 4 patients failed due to conversion to TKA (n = 1) or having final Lysholm scores <65 or less than the preoperative scores (n = 3). The overall Kaplan-Meier probabilities of survival after repair were 99% at 5 years, 98% at 6 years, 95% at 7 years, and 92% at 8 years.

CONCLUSIONS

Among patients with MMPRTs, transtibial pullout repair demonstrated a high clinical survival rate and the patients demonstrated clinical improvement, based on mid- and long-term follow-up examinations.

LEVEL OF EVIDENCE

Level IV, retrospective uncontrolled case series.

Arthroscopic Lateral Meniscal Allograft Transplantation With the Key-Hole Technique

The efficacy of meniscus allograft transplantation (MAT) for the meniscus-deficient knee has been widely recognized as being excellent in terms of pain relief and functional improvement. Lateral MAT is usually performed with the bone bridge technique that uses a bone bridge connecting the anterior and posterior horns of an allograft. The slot position for the meniscal graft insertion is of great importance with the bone bridge technique, especially in the key-hole method. The purpose of this Technical Note is to describe lateral MAT using the key-hole technique in which an allograft with a bone bridge carved to accommodate the key-hole-shaped slot is properly secured to the slot.

Arthroscopic Medial Meniscus Posterior Root Reconstruction Using Auto-Gracilis Tendon

There have been several techniques to repair the medial meniscus posterior root tears (MMPRTs) with the goal of restoring the anatomic and firm fixation of the meniscal root to bone. Many anatomic studies about the menisci also have been developed, so a better understanding of the anatomy could help surgeons perform correct fixation of the MMPRTs. The meniscal roots have ligament-like structures that firmly attach the menisci to the tibial plateau, and this structural concept is important to restore normal biomechanics after anatomic root repair. We present arthroscopic transtibial medial meniscus posterior root reconstruction using auto-gracilis tendon.

Comparison of Poly-L-Lactic Acid and Poly-L-Lactic Acid/Hydroxyapatite Bioabsorbable Screws for Tibial Fixation in ACL Reconstruction: Clinical and Magnetic Resonance Imaging Results

Background

The purpose of this study was to compare the clinical and radiological results of 2 different tibial fixations performed using bioabsorbable screws with added hydroxyapatite (HA) and pure poly-L-lactic acid (PLLA) screws in anterior cruciate ligament (ACL) reconstruction.

Methods

A total of 394 patients who underwent arthroscopic ACL reconstruction between March 2009 and June 2012 were retrospectively reviewed. Of those, 172 patients who took the radiological and clinical evaluations at more than 2 years after surgery were enrolled and divided into 2 groups: PLLA group (n = 86) and PLLA-HA group (n = 86). Both groups were assessed by means of the Lysholm score, International Knee Documentation Committee (IKDC) subjective knee score, and Tegner activity score. Stability was evaluated using the KT-2000 arthrometer. Magnetic resonance imaging was performed to evaluate tibial tunnel widening, screw resorption, osteoingeration, and foreign body reactions.

Results

The PLLA-HA group showed significant reduction in the extent of tibial tunnel widening and foreign body reactions and significant increase in screw resorption compared to the pure PLLA group (p < 0.001 for both). In contrast, postoperative Lysholm score, Tegner activity score, IKDC score, and side-to-side difference on the KT-2000 arthrometer showed no significant differences between groups (p = 0.478, p = 0.906, p = 0.362, and p = 0.078, respectively). The PLLA group showed more significant widening in the proximal tibial tunnel than the PLLA-HA group (p = 0.001). In the correlation analysis, proximal tibial tunnel widening revealed a positive correlation with knee laxity (r = 0.866) and a negative correlation with Lysholm score (r = −0.753) (p < 0.01 for both).

Conclusions

The HA added PLLA screws would be advantageous for tibial graft fixation by reducing tibial tunnel widening, improving osteointegration, and lowering foreign body reactions. Even though no clinically significant differences were noted between the pure PLLA group and PLLA-HA group, widening of the proximal area of the tibial tunnel showed a tendency to increase knee laxity measured using the KT-2000 arthrometer.

Does Release of the Superficial Medial Collateral Ligament Result in Clinically Harmful Effects After the Fixation of Medial Meniscus Posterior Root Tears?

PURPOSE

To investigate pain and tenderness, stress testing, clinical outcome scores, complications, and operation time at 24 months and magnetic resonance imaging (MRI) analysis at 12 months after the release of the distal attachment of the superficial medial collateral ligament (sMCL) during medial meniscus posterior root tear (MMPRT) fixation.

METHODS

Patients who received MMPRT fixation with a follow-up of at least 2 years were included. During fixation, the release of the distal attachment of the sMCL on the proximal tibia was performed to improve visualization and provide sufficient working space. Pain and tenderness at the released area, manual valgus stress tests of 30° and 0° flexion (grade 0/1/2/3), and subjective instability during weight bearing were evaluated serially at postoperative 3, 6, 12, and 24+ months. The contour of detachment area was assessed using MRI 12 months postoperatively. As a subgroup analysis, tourniquet time (minutes) and final clinical scores were compared between release and nonrelease groups.

RESULTS

The numbers of participants in the release and nonrelease groups were 118 and 20 patients, and their mean follow-up durations were 42.4 ± 19.3 (24-95) and 37.2 ± 7.8 (30-55) months, respectively. In the release group, percentages of patients with pain and tenderness at 3 months were 15% and 18%, respectively; however, no patients had symptoms at 12 months. In valgus stress tests (30°, 0°), 12% and 2% of patients showed grade 1 laxity at 3 months, and 7% had grade 1 laxity in only 30° flexion at the final follow-up. However, no patients had subjective valgus laxity. An intact contour was confirmed in all cases among 94 patients checked by performing follow-up MRI. Tourniquet time was significantly shorter in the release group (42.4 ± 19.3) than in the nonrelease group (58.5 ± 9.5; P < .001). Between release and nonrelease groups, Lysholm (84.4 ± 12.1, 88.1 ± 12.8; P = .117) and International Knee Documentation Committee scores (73.6 ± 11.2, 77.5 ± 11.9; P = .112) did not differ.

CONCLUSIONS

The release of the distal attachment of the sMCL during fixation of MMPRT did not result in pain and tenderness, residual instability, and complication. An intact contour of the sMCL was confirmed in all cases with MRI. This procedure reduced operation time and showed similar clinical results when compared between the release and nonrelease groups. However, this study had low power to detect the difference for clinical scores between the 2 groups.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Pullout Fixation of Posterior Medial Meniscus Root Tears: Correlation Between Meniscus Extrusion and Midterm Clinical Results

BACKGROUND

Medial meniscus posterior root tears (MMPRTs) lead to extrusion of the meniscus during weightbearing as well as loss of the ability of the meniscus to generate hoop stress. This loss of load-sharing ability leads to progressive arthritic changes. However, there have been no studies that correlate the correction of meniscus extrusion with clinical outcomes.

HYPOTHESIS

Decreased meniscus extrusion is associated with better clinical and radiographic outcomes compared with increased meniscus extrusion after MMPRT pullout fixation.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

A total of 39 patients who underwent MMPRT pullout fixation and had been observed for more than 5 years were recruited for this study. The mean follow-up period was 69.8 months. Participants were categorized into 2 groups according to the direction of meniscus extrusion: group A (increased extrusion; 23 patients) and group B (decreased extrusion; 16 patients). Meniscus extrusion was assessed in the coronal plane on magnetic resonance imaging preoperatively and at 1 year postoperatively. The postoperative clinical outcomes (Lysholm and International Knee Documentation Committee [IKDC] scores) and radiographic results (Kellgren-Lawrence [K-L] grade and medial joint space) were compared between groups.

RESULTS

Meniscus extrusion in group A increased significantly from a mean (±SD) of 3.5 ± 0.9 mm preoperatively to 5.1 ± 1.4 mm at 1 year postoperatively ( P < .001), whereas in group B, it decreased significantly from 4.1 ± 1.3 mm preoperatively to 3.5 ± 1.4 mm at 1 year postoperatively ( P < .001). The K-L arthritis grade (0/1/2/3/4) significantly progressed in group A (from 2/12/9/0/0 preoperatively to 0/1/14/8/0 postoperatively, respectively; P = .009) but not in group B (from 1/11/4/0/0 preoperatively to 0/6/8/2/0 postoperatively, respectively; P = .274). The mean final Lysholm and IKDC scores in group B (88.1 ± 12.1 and 79.0 ± 11.4, respectively) were significantly better than those in group A (81.0 ± 9.0 and 71.1 ± 7.8, respectively) ( P < .05). There was less medial joint space narrowing at final follow-up in group B (0.6 ± 0.8 mm) than in group A (1.1 ± 0.6 mm) ( P = .015). Progression of the K-L arthritis grade was seen in 50% (8/16) of the patients in group B compared with 87% (20/23) of the patients in group A ( P = .027).

CONCLUSION

The current study demonstrates that in patients with MMPRTs, pullout fixation leads to favorable midterm outcomes, regardless of meniscus extrusion at 1-year follow-up. However, patients with decreased meniscus extrusion at postoperative 1 year have more favorable clinical scores and radiographic findings at midterm follow-up than those with increased extrusion at 1 year. This study indicates that one of the main goals of the repair of MMPRTs is to reduce meniscus extrusion as much as possible.

Biomechanical Analysis of a Novel Wedge Locking Plate in a Porcine Tibial Model

Background

The purpose of this study was to analyze biomechanical properties of a novel wedge locking plate in medial open wedge high tibial osteotomy (OWHTO) in a porcine tibial model.

Methods

A uniform 8-mm OWHTO was performed in 12 porcine tibiae. Six of them were subsequently fixed with the plate without a wedge, whereas the other 6 were additionally reinforced with a metal wedge of 8 mm. Biomechanical properties (stiffness, displacement of the osteotomy gap, and failure load) were evaluated under axial load. The different modes of failure were also investigated.

Results

The plate showed an axial stiffness of 2,457 ± 450 N/mm with a wedge and 1,969 ± 874 N/mm without a wedge. The maximum failure load was 5,380 ± 952 N with a wedge and 4,354 ± 607 N without a wedge. The plate with a wedge had a significantly greater failure load and significantly less displacement of medial gap at failure than that without a wedge (p = 0.041 and p = 0.002, respectively). The axial stiffness was not different between the two types of fixation. Most failures were caused by lateral cortex breakage and there was no implant failure.

Conclusions

The novel wedge locking plate showed excellent biomechanical properties and an additional wedge provided significant improvement. This plate can be a good fixation method for OWHTO.

Prognostic Factors in the Midterm Results of Pullout Fixation for Posterior Root Tears of the Medial Meniscus

PURPOSE

To identify predictors of unfavorable clinical and radiologic outcomes a minimum of 5 years after pullout fixation for medial meniscus posterior root tears (MMPRTs).

METHODS

In total, 40 patients who were followed for >5 years after pullout fixation in MMPRT were recruited. The mean follow-up duration was 71.1 months. Clinical outcomes, including Lysholm score and International Knee Documentation Committee (IKDC) score, and radiographic results, including Kellgren-Lawrence (K-L; 0/1/2/3/4) grade and medial joint space width, were evaluated preoperatively and at final follow-up. Preoperative prognostic factors, including age, sex, body mass index, degree of varus alignment, K-L grade, medial joint space width, meniscal extrusion, and cartilage status, by the modified Outerbridge classification (grades 1 or 2 v 3 or 4), for relatively unfavorable (fair or poor grade) Lysholm or IKDC score, and progression of K-L grade were investigated by multivariate logistic regression analysis.

RESULTS

The mean Lysholm score (52.1 ± 8.8 to 83.8 ± 11.9) and IKDC score (40.1 ± 7.6 to 73.3 ± 10.9) were improved significantly (P < .001), although the loss of medial joint space width (4.8 ± 1.1 to 3.9 ± 1.1 mm) and K-L grade (6/25/9/0/0 to 0/11/20/9/0) progressed significantly (P < .001). Unfavorable prognostic factors of the Lysholm score were grade ≥3 chondral lesions (odds ratio [OR] = 5.993; P = .028) and varus mechanical alignment (OR = 1.644; P = .017), for IKDC score were grade ≥3 chondral lesions (OR = 11.146; P = .038) and older age (OR = 1.200; P = .017). Preoperative chondral lesion grade ≥3 increased the risk of K-L grade progression (OR = 11.000; P = .031).

CONCLUSIONS

Clinically, modified Outerbridge classification grade ≥3 chondral lesions, varus alignment, and older age were found to predict a poor prognosis after MMPRT fixation. In terms of radiographic K-L grade progression, grade ≥3 chondral lesions were identified as a poor prognostic factor.

LEVEL OF EVIDENCE

Level IV, case series.

A meta-analysis of clinical and radiographic outcomes of posterior horn medial meniscus root repairs

PURPOSE

Although interest in medial meniscus posterior root tear (MMPRT) repair has increased, few case series have been reported. This meta-analysis aimed to examine the clinical and radiological effects of MMPRT repair by pooling pre- and post-operative data from case-series reports.

METHODS

A literature search was performed using MEDLINE/PubMed, the Cochrane Central Register of Controlled Trials, and EMBASE databases. Pre- and post-operative data were pooled to investigate the effects of MMPRT repair, including the Lysholm score improvement, meniscal extrusion (mm) reduction, progression of the Kellgren-Lawrence (K-L) grade, and cartilage status according to the Outerbridge classification. Treatment effects included paired standardized mean differences (difference in the pre- and post-operative mean outcomes divided by the standard deviation) for the Lysholm score and meniscal extrusion, as well as the pooled event rates of progression of K-L grade and cartilage status.

RESULTS

As treatment effects, the Lysholm score increased by as much as 3.675 (P < 0.001), whereas meniscus extrusion was not reduced (n.s.). The overall pooled event rates of progression of K-L grade and cartilage status were 10.6 and 17.3 % (P < 0.001), respectively.

CONCLUSIONS

According to the current literature, MMPRT repair resulted in significant improvements in the post-operative clinical subjective scores compared with the preoperative status. However, meniscus extrusion was not reduced. Considering the occurrence of progression of K-L grade and cartilage status, it did not prevent the progression of arthrosis completely. Based on these results, repair results in favourable outcomes for MMPRT.

LEVEL OF EVIDENCE

Meta-analysis, Level IV.

Arthroscopic Medial Meniscus Posterior Root Fixation Using a Modified Mason-Allen Stitch

A complete radial tear of the meniscus posterior root, which can effectively cause a state of total meniscectomy via loss of hoop tension, requires that the torn root be repaired. Several methods have been used to repair medial meniscus posterior root tears, most of which are based on a simple stitch technique that is known to have stitch-holding strength. We applied a modified version of the Mason-Allen stitch technique, which is recognized as a method for rotator cuff repair surgery because its locking effect overcomes the potential weakness of simple stitches. This article introduces the medial meniscus posterior root tears repair procedure based on a modified Mason-Allen stitch technique in which 2 strands (i.e., 1 simple horizontal and 1 simple vertical stitch) are used.

Double metal tibial blocks augmentation in total knee arthroplasty

PURPOSE

Severe uncontained tibial bone defects occurring during total knee arthroplasty are challenging, and which treatment method is the best remains unknown. In this study, clinical and radiographic outcomes of double metal blocks augmentation were examined.

METHODS

Between 2004 and 2012, double metal blocks augmentation was carried out in 17 patients with severe asymmetric uncontained tibial bone defects. The first block was attached to the tibial tray with screws, and then the second block was cemented to the first block. Out of 17 patients, 13 (8 primary, 5 revision) were available for final follow-up at a median of 69 months (range 24-99). For clinical assessment, range of motion and Knee Society score were evaluated preoperatively and annually thereafter. At the final follow-up, Western Ontario and McMaster Universities Osteoarthritis Index, Oxford knee, Short Form-36, Lower extremity functional scale, and Lower extremity activity scale scores were evaluated. Radiographic assessment for radiolucent lines at the block-cement-bone interfaces and signs of failure was performed annually using fluoroscopy and standard radiographs.

RESULTS

Range of motion and Knee Society score were significantly improved post-operatively. Other clinical outcomes were favourable. Radiolucent lines were seen on fluoroscopy in three knees, but no sign of failure, such as loosening, collapse, or instability, was observed at the final follow-up.

CONCLUSIONS

Double metal blocks augmentation is a favourable and useful method, which does not cause mechanical failure or protrusion of the prosthetic because of its modularity, to manage severe asymmetric uncontained proximal tibial bone defects >15 mm in total knee arthroplasty.

LEVEL OF EVIDENCE

Case series, Level IV.

Are Muscle Strength and Function of the Uninjured Lower Limb Weakened After Anterior Cruciate Ligament Injury? Two-Year Follow-up After Reconstruction

BACKGROUND

After an anterior cruciate ligament (ACL) injury, the uninjured contralateral lower limb may become weakened because of neuromuscular changes, proprioceptive deficits, and disuse of the limb; this weakness predisposes the limb to ACL injury. However, no results have been reported regarding weakness in the contralateral limb after ACL injury.

HYPOTHESIS

Muscle strength and functional status of the contralateral lower limb are reduced after unilateral ACL injury.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

The ACL group consisted of 75 patients who underwent primary unilateral ACL reconstruction and were followed at 3, 6, 12, and 24 months postoperatively. A group of 75 healthy individuals (controls) were matched one-to-one with the ACL group for age, sex, body mass index, and initial Tegner activity level. The side that was evaluated in each control subject corresponded to the injured limb in the matched ACL subject. Isokinetic muscle strength, including extension peak torque per body weight (EPT) and flexion peak torque per body weight (FPT), was evaluated at angular velocities of 60 and 180 deg/s. Patients were also evaluated by single-legged hop test.

RESULTS

Compared with the EPT at 60 deg/s in the control group (290.9 ± 40.1 N · m/kg), the value in the ACL group 24-month follow-up (276.6 ± 42.8 N · m/kg) as well as other follow-up times was significantly lower (P < .05), whereas the EPT at 180 deg/s and the FPT at 60 and 180 deg/s in the ACL group were significantly lower than the control group at 3-month follow-up but were restored to normal levels at final follow-up. Results from the single-legged hop test demonstrated that the ACL group performed at a significantly lower level than the control group at 24-month follow-up (158.4 ± 25.3 vs 176.3 ± 24.7 cm; P < .05) as well as other follow-up times. However, both measurements improved significantly as the follow-up time progressed.

CONCLUSION

After ACL injury, isokinetic extensor muscle strength and functional status of the contralateral limb were reduced, even at 24 months after ACL reconstruction. However, both measurements improved significantly as the follow-up time progressed. In contrast, flexion muscle strength was restored to normal levels. Therefore, care should be taken to restore muscle strength and functional status in not only the ACL-reconstructed knee but also the uninjured limb.

Comparison of Clinical and Radiologic Results Between Partial Meniscectomy and Refixation of Medial Meniscus Posterior Root Tears: A Minimum 5-Year Follow-up

PURPOSE

To compare the clinical and radiologic results of partial meniscectomy with those of refixation in patients with medial meniscus posterior root tears (MMPRTs) at a minimum 5-year follow-up.

METHODS

Between 2005 and 2009, patients with MMPRTs who had been followed up for at least 5 years after a partial meniscectomy (group M, n = 20) or pullout repair (group R, n = 37) were recruited. The mean follow-up duration was 67.5 months in group M and 72.0 months in group R. Clinical assessments, including the Lysholm score and International Knee Documentation Committee (IKDC) Subjective Knee Form score, and radiographic assessments, including the Kellgren-Lawrence (K-L) grade and medial joint space width, were evaluated preoperatively and at final follow-up. We compared the preoperative results with the final results in each group, and we compared the final results of groups M and R. Five-year survival rates were also evaluated.

RESULTS

The mean Lysholm score (P = .039) and IKDC score (P = .037) improved significantly. However, the width of the medial joint space (P < .001) and K-L grade (P < .001) worsened significantly in both groups. When we compared the final results, group R had significantly better Lysholm scores (P = .002) and IKDC scores (P < .001) than group M. Group R showed less K-L grade progression (P = .005) and less medial joint space narrowing (P < .001) than group M. The rate of conversion to total knee arthroplasty was 35% in group M, whereas there was no conversion to total knee arthroplasty in group R. The 5-year survival rates in groups M and R were 75% and 100%, respectively (P < .001).

CONCLUSIONS

For MMPRTs, refixation was more effective than partial meniscectomy in terms of the clinical and radiologic outcomes and survival for at least 5 years' follow-up. Refixation slowed the progression of arthritic changes compared with partial meniscectomy, although it did not prevent the progression of arthrosis completely.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Isolation and characterization of factor IX Chapel Hill: comparison to normal human factor IX

A classification scheme for patients with hemophilia B has been devised. Assessment of factor IX antigen and factor IX coagulant activity has confirmed the genetic heterogeneity of hemophilia B and has shown that some affected patients have normal amounts of factor IX-like protein. An abnormal factor IX, factor IX Chapel Hill, has been isolated from one of these variants and compared structurally and functionally to the purified normal human factor IX molecule. The major difference between factor IX Chapel Hill and normal human factor IX appears to be defective activation of the abnormal molecule by factor XIa and calcium.

Risk factors of delirium in patients undergoing total knee arthroplasty

Although postoperative delirium is a complicated disorder in elderly individuals, no study has been examined the risk factors associated with perioperative comorbidities and clinical laboratory data while specifically focusing on only total knee arthroplasty (TKA). In the present retrospective study, we aimed to evaluate the incidence and perioperative risk factors of postoperative delirium after TKA. Between April 2009 and May 2013, 287 patients (365 knees) aged >65 years who had undergone primary TKA were enrolled. These patients were assigned to the delirium group of 11 patients (11 knees) or the non-delirium group of 276 patients (354 knees). The incidence of delirium among the patients was 3.1% (11/365). Univariate logistic regression analysis indicated that a history of dementia, older age, lower body mass index (BMI) level, and a postoperative day 3 blood urea nitrogen (BUN) level of >14.9 mg/dL were risk factors. However, multivariate logistic regression analysis indicated that a history of dementia (adjusted odds ratio [AOR]: 10.4, [1.09, 100]), older age (AOR: 1.15, [1.01, 1.31]), and a postoperative day 3 BUN level of >14.9 mg/dL (AOR: 4.76, [1.15, 19.7]) were independent risk factors. Based on our findings, we believe that the surgeons should be careful to avoid the postoperative delirium and ensure the appropriate management for patients who have these risk factors.

Successful endoscopic hemoclipping of massive lower gastrointestinal bleeding from paratyphoid A fever

Paratyphoid fever can be complicated by massive lower gastrointestinal bleeding with ileocolonic ulcerations, which are commonly localized using colonoscopy. The most common manifestations include multiple, variable-sized, round or oval-shaped, punched-out ulcers. Occasionally, massive lower gastrointestinal bleeding can occur from erosion of blood vessels. We present a rare case of severe lower gastrointestinal bleeding due to paratyphoid A fever that was successfully controlled with hemoclippings. A 30-year-old man experienced high fever and hematochezia whose blood culture showed Salmonella paratyphi A. A complete colonoscopy was successfully performed up to the level of the terminal ileum, which showed multiple, shallow, ulcerated lesions over the entire terminal ileum. A bleeding vessel was seen in one of the ulcers, with overlaying blood clots. Endoscopic hemostasis was successfully performed with four pieces of endoclip and without immediate complication. This report highlights the use of colonoscopy and endoscopic therapy with endoclips for lower gastrointestinal bleeding, which should be considered before surgery.

Association between vitamin D deficiency and tuberculosis in a Korean population

BACKGROUND

Several in vitro studies have been conducted regarding the immunomodulatory and mycobactericidal roles of vitamin D in tuberculous infection. However, discrepancies exist among epidemiological studies. We compared vitamin D deficiency between patients with tuberculosis (TB) and healthy control subjects and identified risk factors for vitamin D deficiency.

METHOD

This was an age- and sex-matched case-control analysis of 94 TB cohort and 282 Korean national survey participants.

RESULTS

The median baseline 25-hydroxyvitamin D (25[OH]D) level in the TB group (9.86 ng/ml, IQR 7.19-14.15) was lower than in controls (16.03 ng/ml, IQR 12.38-20.30, P < 0.001). The prevalence of severe vitamin D deficiency was higher in patients with TB (51.1%) than in controls (8.2%, P = 0.001). The median 25(OH)D level increased from 11.40 ng/ml (IQR 7.85-15.73) to 13.18 ng/ml (IQR 10.60-19.71) after treatment completion (P = 0.037). On multivariate analysis, presence of TB and history of TB were independently associated with severe vitamin D deficiency.

CONCLUSION

Patients with TB had a higher prevalence of vitamin D deficiency than control subjects in a Korean population. The median 25(OH)D level increased after TB treatment. Further studies are needed to establish a causal relationship.

Massive lower gastrointestinal bleeding from the appendix

Massive rectal bleeding from the appendix, considered a rare case of lower gastrointestinal bleeding, is not easily recognized by various diagnostic modalities. A multidisciplinary approach for both a diagnosis and a differential diagnosis is important because the identification of the bleeding site is crucial to proceed to a proper intervention and there are various causes of appendiceal bleeding. Because early colonoscopy plays an important role in the diagnosis and management of lower gastrointestinal hemorrhage, we report a case of a life threatening massive rectal bleeding from the appendix diagnosed by colonoscopy. We also present a review of the literature.

Natural nanocontainer for the controlled delivery of glycerol as a moisturizing agent

Natural halloysite nanotubes with a 15-nm internal lumen and a 50 nm outer diameter were investigated as a nanocontainer for the loading and extended release of glycerol for cosmetic applications. Cytotoxicity testing of the halloysite was conducted on 3T3 and MCF-7 cells, and the tubules showed no toxic effect on the cells for over 48 h. The capability of halloysite for loading glycerol was higher with the USA halloysite than with the New Zealand's, being approximately 20% and 2.3% by weight, respectively. The total elapsed time for releasing glycerol from the nanotubes exceeded 20 h. To further retard the glycerol release rate, the halloysite samples filled with glycerol were coated with several alternate layers of polyethyleneimine and polyacrylic acid. The release rate remained at the same level, however, probably due to the low molecular weight of the polyelectrolytes and the high solubility of glycerol in water.

Concurrent reactivation of latent EBV with hepatitis A can affect clinical feature of childhood hepatitis

AIMS

Some children with acute hepatitis A virus (HAV) infection have concurrent Epstein-Barr virus (EBV) reactivation serologically. We studied the frequency of EBV reactivation during HAV infection and determined whether simultaneous occurrence of EBV reactivation and HAV infection affected the clinical features of HAV infection.

METHODS

The medical records of patients under 19 years of age diagnosed with acute hepatitis A between January 1996 and June 2009 were reviewed.

RESULTS

Among 72 patients with acute hepatitis A, 22 patients (30.6%) had EBV reactivation. A markedly prolonged duration of full recovery from hepatitis was observed in reactivated group. The peak levels of AST and ALT in reactivated group were higher than non-reactivated group (p = 0.012 and p < 0.001, respectively). Higher peak levels of AST and ALT in reactivated subgroups over 10 years old were observed compared to non-reactivated subgroup (p = 0.027 and p = 0.001, respectively). Duration of recovery showed significant differences between two subgroups.

CONCLUSIONS

Concurrent reactivation of latent EBV and HAV infections is common. EBV reactivation with HAV infection adversely affects the clinical feature of hepatitis. Therefore, we should keep in mind that the concurrence especially in older children may cause worse injury to the liver.

Development of LiF:Mg,Cu,Si TL material (new KLT-300) with a low-residual signal and high-thermal stability

LiF-based thermoluminescence (TL) materials have been widely used for radiation dosimetry due to their attractive features. LiF:Mg,Cu,P is one of the most sensitive tissue-equivalent TL materials, approximately 40 times more sensitive than LiF:Mg,Ti (TLD-100), but it has two main drawbacks: a thermal loss of the TL sensitivity when annealed at temperatures>240 degrees C, and a relatively high-residual signal. Recently, LiF:Mg,Cu,Na,Si TL material was developed to overcome these drawbacks at the Korea Atomic Energy Research Institute, but it provided only marginal improvements in reducing the residual signal. The newly developed LiF:Mg,Cu,Si TL material has a significantly lower residual signal and a better stability to thermal treatments. In this article, the preparation method and some dosimetric properties (sensitivity and residual signal) of the new LiF:Mg,Cu,Si TL material are presented. At the end of the preparation procedures, a dual-step annealing method is introduced and this has proved as a very efficient method to reduce the high-temperature peak and is the cause of residual signal. Therefore, the high-temperature peak in the glow curve was significantly reduced. The sensitivity is approximately 20 times higher than that of TLD-100 and the residual signal was estimated to be approximately 0.04%.

Immunopotentiating effect of a Fomitella fraxinea-derived lectin on chicken immunity and resistance to coccidiosis

This study reports a novel immunopotentiating effect of a lectin (FFrL) extracted from the mushroom Fomitella fraxinea on poultry cell-mediated immunity and poultry coccidiosis. We describe the extraction of FFrL, its in vitro mitogenic activity and in vivo protection against an oral challenge infection with Eimeria acervulina. When tested on several cell types, crude FFrL agglutinated mouse erythrocytes and thymocytes and various other cells including murine and human cell lines. However, crude FFrL did not agglutinate human erythrocytes. Crude FFrL showed a potent mitogenic activity on chicken splenic lymphocytes, and at lower concentrations it exerted stronger mitogenic activity than Concanavalin A, a well-known potent mitogen for lymphocytes. Further, FFrL significantly induced (P < 0.05) nitric oxide secretion in HD11 cells and suppressed (P < 0.05) RP9 tumor cell growth in a dose-dependent fashion. When injected into 18-d-old chicken embryos followed by a posthatch oral E. acervulina challenge infection, FFrL treatment significantly protected chickens against weight loss associated with coccidiosis (P < 0.05). Injecting embryos with FFrL also resulted in significant reduction in oocyst shedding as compared with the control saline-injected birds (P < 0.05). The results of this study demonstrate that FFrL can be an effective growth promoting and immunostimulating agent in poultry during coccidiosis.

Dosimetric properties of the newly developed KLT-300 (LiF:Mg,Cu,Na,Si) TL detector

The dosimetric properties of the newly developed KLT-300 (KAERI LiF:Mg,Cu,Na,Si TL detector) in KAERI (Korea Atomic Energy Research Institute) were investigated. The sensitivity of the TL detector was about 30 times higher than that of the TLD-100 by light integration. In the study of the dose linearity of the detector, the dose response was very linear up to 10 Gy and a sublinear response was observed at higher doses. The energy response of the detector was studied for photon energies from 20 to 662 keV. The results show that a maximum response of 1.004 at 53 keV and a minimum response of 0.825 at 20 keV were observed. The reproducibility study for the TL detector was also carried out. The coefficients of variation for each detector separately did not exceed 0.016, and for all the 10 detectors collectively it was 0.0054. IEC Standard requires that the coefficient of variation shall not exceed 0.075. So, the reproducibility of this new TL detector sufficiently satisfied the IEC requirements. A detection threshold of the detector was investigated and found to be 70 nGy by Harshaw 4500 TLD Reader.

On the roles of the dopants in LiF: Mg,Cu,Na,Si thermoluminescent material

In this paper, some results of the study on the roles of the dopants in the LiF:Mg,Cu,Na,Si thermoluminescent (TL) material that was developed at the Korea Atomic Energy Research Institute for radiation protection are presented. Although there have been many studies to investigate the roles of the dopants in LiF:Mg,Cu,P TL material in the TL process, there are some discrepancies in the understanding of the roles of Cu and P between various researchers. In case of LiF:Mg,Cu,Na,Si TL material, there are a few studies on the roles of the dopants. Three kinds of samples in each of which one dopant is excluded, and the optimised sample, were prepared for this study. The measurements and analysis of the three-dimensional TL spectra, based on the temperature, wavelength and intensity, and the glow curves for those samples are used in this study. The results show that Mg plays a role in the trapping of the charge carriers and Cu plays a role in the luminescence recombination process; however, the effect of Na and Si on the glow curve structure and the TL emission spectra is much less than that of Mg and Cu. It is considered that Na and Si each plays a role in the improvement of the luminescence efficiency.

A computer program for the deconvolution of thermoluminescence glow curves

A quick and efficient computer program was developed in order to resolve the peaks from the thermoluminescence (TL) glow curve. The program was designed to be easily used on any MS Windows-based computer with a graphical user interface. In this program, a new method based on the general one-trap TL equation was adopted to analyse the TL glow curve with the traditional first-order, second-order and general-order kinetics model. The method described here, general approximation, generates TL glow peaks and interpolates the relevant TL parameters from the glow data. The program was tested with simulated and experimental TL glow data and the results were found to be adequate and reliable.