Minimally invasive anterolateral approach versus lateral transmuscular approach for total hip arthroplasty: A systematic review and meta-analysis.

BACKGROUND: Total hip arthroplasty (THA) using a minimally invasive (MI) approach is a commonly performed procedure, and several approaches are now being used clinically. The MI anterolateral (MIAL) approach is one of the MI approaches used in clinical practice. Whether the MIAL approach is superior to non-MI approaches remains controversial. To resolve this controversy, we performed a systematic review and a meta-analysis of results of THA procedures that used the MIAL approach. We assessed whether the MIAL approach was superior to the lateral transmuscular (LT) approach in terms of operative time, operative blood loss, radiological parameters, and clinical outcomes. METHODS: We performed a methodical search for all literature published on PubMed, Web of Science, and the Cochrane Library, and pooled data using the RevMan software. A p value < 0.05 was considered statistically significant. We calculated the mean differences (MD) for continuous data with 95% confidence intervals (CI) for each outcome. RESULTS: This meta-analysis included 6 studies. Pooled results indicated no statistically significant differences between the groups in terms of operative time (MD = 5.13, 95% CI -2.49 to 12.75, p = 0.19), cup abduction angle (MD = 1.64, 95% CI -1.32 to 4.60, p = 0.28), and cup anteversion angle (MD = 0.75, 95% CI -1.09 to 2.59, p = 0.43). Operative blood loss was significantly greater in those who underwent THA via the MIAL approach than those who underwent THA via the LT approach (MD = 68.01, 95% CI 14.69 to 121.33, p = 0.01). The postoperative Harris hip score (HHS) assessed at the time of final follow-up was significantly higher in those who underwent THA via the MIAL approach than those who underwent THA via the LT approach (MD = 1.41, 95% CI 0.50 to 2.33, p = 0.002). CONCLUSION: We conclude that the MIAL approach is superior to the LT approach in terms of clinical outcomes. LEVEL OF EVIDENCE: Level Ⅱ.

[Reliability and validity of the Japanese version of the Thinking Style Inventory].

This study examined the internal and external validity of the Japanese version of the Thinking Styles Inventory (TSI: Hiruma, 2000), which was originally developed by Sternberg and Wagner (1991) based on the framework of Sternberg's (1988) theory of mental self-government. The term "thinking style" refers to the concept that individuals differ in how they organize, direct, and manage their own thinking activities. We administered the Japanese version of the TSI to Japanese participants (N = 655: Age range 20-84 years). The results of item analysis, reliability analysis, and factor analysis, were consistent with the general ideas of the theory. In addition, there were significant relationships between certain thinking styles and 3 participant characteristics: age, gender, and working arrangement. Furthermore, some thinking styles were positively correlated with social skill. Implications of these results for the nature of Japanese thinking styles are discussed.

Quantitative evaluation of fatty degeneration of the supraspinatus and infraspinatus muscles using T2 mapping.

BACKGROUND: Although fatty degeneration of the rotator cuff muscles has been reported to affect the outcomes of rotator cuff repairs, only a few studies have attempted to quantitatively evaluate this degeneration. T2 mapping is a quantitative magnetic resonance imaging technique that potentially evaluates the concentration of fat in muscles. The purpose of this study was to investigate fatty degeneration of the rotator cuff muscles by using T2 mapping, as well as to evaluate the reliability of T2 measurement. METHODS: We obtained magnetic resonance images including T2 mapping from 184 shoulders (180 patients; 110 male patients [112 shoulders] and 70 female patients [72 shoulders]; mean age, 62 years [range, 16-84 years]). Eighty-three shoulders had no rotator cuff tear (group A), whereas 101 shoulders had tears, of which 62 were incomplete to medium (group B) and 39 were large to massive (group C). T2 values of the supraspinatus and infraspinatus muscles were measured and compared among groups. Intraobserver and interobserver variabilities also were examined. RESULTS: The mean T2 values of the supraspinatus in groups A, B, and C were 36.3 ± 4.7 milliseconds, 44.2 ± 11.3 milliseconds, and 57.0 ± 18.8 milliseconds, respectively. The mean T2 values of the infraspinatus in groups A, B, and C were 36.1 ± 5.1 milliseconds, 40.0 ± 11.1 milliseconds, and 51.9 ± 18.2 milliseconds, respectively. The T2 value significantly increased with the extent of the tear in both muscles. Both intraobserver and interobserver variabilities were more than 0.99. CONCLUSION: T2 mapping can be a reliable tool to quantify fatty degeneration of the rotator cuff muscles.

Transient heating of expressed breast milk up to 65°C inactivates HIV-1 in milk: a simple, rapid, and cost-effective method to prevent postnatal transmission.

The postnatal transmission of human immunodeficiency virus (HIV) from mothers to children occurs through breastfeeding. Although heat treatment of expressed breast milk is a promising approach to make breastfeeding safer, it is still not popular, mainly because the recommended procedures are difficult to follow, or time-consuming, or because mothers do not know which temperature is sufficient to inactivate HIV without destroying the nutritional elements of milk. To overcome these drawbacks, a simple and rapid method of heat treatment that a mother could perform with regular household materials applying her day-to-day art of cooking was examined. This structured experiment has demonstrated that both cell-free and cell-associated HIV type 1 (HIV-1) in expressed breast milk could be inactivated once the temperature of milk reached 65°C. Furthermore, a heating method as simple as heating the milk in a pan over a stove to 65°C inhibited HIV-1 transmission retaining milk's nutritional key elements, for example, total protein, IgG, IgA, and vitamin B(12) . This study has highlighted a simple, handy, and cost-effective method of heat treatment of expressed breast milk that mothers infected with HIV could apply easily and with more confidence.

Quality of gastric cancer care in designated cancer care hospitals in Japan.

OBJECTIVE: To develop a set of process-of-care quality indicators (QIs) that would cover a wide range of gastric cancer care modalities and to examine the current state of the quality of care provided by designated cancer care hospitals in Japan. DESIGN: A retrospective medical record review. SETTING: Eighteen designated cancer care hospitals throughout Japan. PARTICIPANTS: A total of 1685 patients diagnosed with gastric cancer in 2007. MAIN OUTCOME MEASURES: Provision of care to eligible patients as described in the 29 QIs, which were developed using an adaptation of the RAND/UCLA (University of California, Los Angeles) appropriateness method by a panel of nationally recognized experts in Japan. RESULTS: Overall, the patients received 68.3% of the care processes recommended by the QIs. While 'deep venous thrombosis prophylaxis before major surgery' was performed for 99% of the cases, 'documentation before endoscopic resection' was completed for only 12% of the cases. The chemotherapy care was less likely to meet the QI standards (61%) than pre-therapeutic care (76%), surgical treatment (66%) and endoscopic resection (71%; overall difference: P < 0.001). A comparison based on the types of care showed that documentation and patient explanation were performed less frequently (60 and 53%, respectively) than were diagnostic and therapeutic processes as recommended in the QIs (85%; overall P < 0.001). CONCLUSIONS: Although many required care processes were provided, some areas with room for improvement were revealed, especially with respect to chemotherapy, documentation and patient explanation. Continuous efforts to improve the quality and develop a system to monitor this progress would be beneficial in Japan.

A novel therapeutic strategy for chylous ascites after gynecological cancer surgery: a continuous low-pressure drainage system.

PURPOSE: Postoperative chylous ascites is an unusual complication following retroperitoneal surgery. A search of the English literature showed only 44 cases of chylous ascites following gynecological cancer surgery. The treatment is primarily conservative, but surgical treatment is considered in resistant cases. We developed a novel non-surgical therapeutic strategy for postoperative chylous ascites. METHODS: We report a case of severe chylous ascites following pelvic lymph node dissection for gynecological cancer. RESULTS: Total abdominal hysterectomy, bilateral salpingo-oophorectomy, peritoneal washing, and systematic pelvic lymph node dissection were performed for a stage II G1 endometrioid adenocarcinoma (FIGO 2009). Forty-one days after surgery, the patient was readmitted due to massive ascites. Repeated paracentesis and a low-fat diet were only partially effective. Fifty-one days after surgery, we started paracentesis with a continuous low-pressure drainage system. Nine days later, there was no further fluid drainage. The patient was asymptomatic and without recurrent disease at follow-up 3 months later. CONCLUSIONS: Pelvic lymph node dissection may cause postoperative chylous ascites. Paracentesis with a continuous low-pressure drainage system can be an effective conservative treatment for postoperative chylous ascites.

Mechanism of the compression effect on visual duration perception caused by temporally sandwiching sounds.

When task-irrelevant nontarget sound temporally sandwiches brief target visual stimuli, its perceived duration is compressed (time compression). Since little is known about the mechanisms of time compression, this study examined its causal factors. Experiment 1 measured the effects of preceding, trailing, and sandwiching sounds on visual duration perception and examined whether adding the first two effects predicts the empirical effect of the third. The time compression occurred only when the target visual stimulus was 300 ms, but not for a target duration ≥500 ms. However, the predicted additive effect did not match the time compression. Experiment 2 examined the weighted integration of unisensory estimates (visual filled interval and auditory empty interval) by measuring the perceived duration of unimodal and multimodal stimuli. The predicted duration by weighted integration fitted the time compression occurring at the target duration of 300 ms. However, when the target was 500 ms or longer, no time compression occurred and the predicted durations were longer than the empirical durations. These results suggest that the visual system with weak temporal resolution integrated more accurate and reliable temporal information, rather than additive effect, resulting in time compression only when the target duration was too short. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Mobile application for home exercise adherence in patients with knee osteoarthritis: A pilot study.

BACKGROUND: The adherence to home exercise is generally low despite its well-known effect on knee osteoarthritis. Therefore, we developed a home exercise application, LongLifeSupport, to provide patients with daily basic exercise videos and an automatic recording calendar. We hypothesized that this application would encourage patients to exercise and help maintain their motivation; this pilot study aimed to determine their exercise adherence rates. Using outcome measures, we also aimed to determine the effect of home exercise using this application and the factors for its continuation. METHODS: Twenty patients with knee osteoarthritis were included. The participants exercised for 12 weeks. Using pre- and post-tests, we examined their satisfaction with continuation (only in the post-test), Japanese knee osteoarthritis measure score, short physical performance battery score, bilateral knee extension muscle strength, and short test battery for locomotive syndrome. Furthermore, we investigated correlations between adherence rates and pretest scores of Japanese knee osteoarthritis measure and short test battery and between pretest scores and variations in Japanese knee osteoarthritis measure and short test battery. RESULTS: The mean adherence rate was 82.4%. The participants showed ease of continuation (100%) and significant improvements in the degree of knee pain, pain, and stiffness, and daily life conditions using the Japanese knee osteoarthritis measure score, total score, walk seconds, and chair stand seconds of the short physical performance battery, as well as the extension muscle strength of the right- and pain-side knee. No significant correlations were identified between the adherence rate and the pretest or variation. CONCLUSION: The adherence rate to the application was over 80%. Participants with knee osteoarthritis showed almost full satisfaction, reduced pain, and improved physical ability. Therefore, the use of this application provided a safe exercise program and maintained the exercise motivation of participants. Thus, it may be useful for unsupervised home exercise.

Comparison between ilioinguinal approach and modified Stoppa approach for the treatment of acetabular fractures: An updated systematic review and meta-analysis.

BACKGROUND: The modified Stoppa (MS) approach is an alternative to the ilioinguinal (IL) approach and three meta-analyses comparing these two approaches for the treatment of acetabular fractures were published previously. The aim of this study was to provide an updated systematic review and meta-analysis comparing the MS approach with the IL approach for the treatment of acetabular fractures and to answer the following question: are the results of the MS approach superior to those of the IL approach in terms of reduction quality, operative time, operative blood loss, complications, and clinical outcomes for treatment of acetabular fractures? PATIENTS AND METHODS: An updated systematic literature review was conducted using relevant original studies from various databases (PubMed, Web of Science and the Cochrane Library). Pooling of data was performed using RevMan software (version 5.3, Cochrane Collaboration, Oxford, UK). A p-value of<0.05 was considered to be significant. We calculated the mean differences (MDs) for continuous data and odds ratio (OR) for dichotomous data with 95% confidence intervals (CIs) for each outcome. Statistical heterogeneity was assessed based on I2 using the standard Chi2 test. When I2>50%, significant heterogeneity was assumed and a random-effects model was applied for the meta-analysis. A fixed-effects model was applied in the absence of significant heterogeneity. RESULTS: Six studies were included in this meta-analysis. The findings demonstrated that the rate of anatomical reduction was significantly higher in the MS approach than in the IL approach (I2=0%, OR=1.75, 95% CI: 1.13-2.69, p=0.01), the operative time was significantly shorter in the MS approach than in the IL approach (I2=88%, MD=-63.60, 95% CI: -93.01 - (-34.20), p<0.0001) and operative blood loss was significantly lower in the MS approach than in the IL approach (I2=75%, MD=-350.51, 95% CI: -523.45 - (-177.58), p<0.0001). There was no significant difference in the rate of nerve injury (I2=0%, OR=0.47, 95% CI: 0.16-1.39, p=0.17), the rate of vascular injury (I2=0%, OR=0.51, 95% CI: 0.17-1.49, p=0.22), the rate of infection (I2=0%, OR=0.53, 95% CI: 0.25-1.12, p=0.10), the rate of heterotopic ossification (I2=45%, OR=0.63, 95% CI: 0.22-1.85, p=0.40), and the rate of excellent or good clinical score (I2=21%, OR=1.15, 95% CI: 0.56-2.38, p=0.70) between the two approaches. DISCUSSION: The MS approach provided better reduction quality, shorter operative time, lower operative blood loss, although there were no significant differences in the rate of complications, and excellent or good clinical score between the two approaches. LEVEL OF EVIDENCE: III.

Quantitative T2 mapping of femoral head cartilage in systemic lupus erythematosus patients with noncollapsed osteonecrosis of the femoral head associated with corticosteroid therapy.

PURPOSE: To evaluate articular cartilage degeneration with transverse relaxation time (T2) mapping in systemic lupus erythematosus (SLE) patients with noncollapsed and asymptomatic osteonecrosis of the femoral head associated with corticosteroids. MATERIALS AND METHODS: T2 mapping with a 1.5-T magnetic resonance imaging system was prospectively performed for 28 normal hips from 14 healthy volunteers (control group) and 15 hips from 10 SLE patients that met the inclusion criteria of noncollapsed and asymptomatic osteonecrosis of the femoral head (osteonecrosis group). Exclusion criteria were past experience of pain, trauma, infection, or prior hip joint surgery. Distribution of T2 values of the femoral head cartilage were compared between the control group and the osteonecrosis group with respect to acetabular dysplasia by center-edge angle (CEA). RESULTS: T2 values of the femoral head cartilage were significantly higher in the osteonecrosis group than in the control group (34.4 msec vs. 30.8 msec, P = 0.001). Multiple regression analysis revealed that the osteonecrosis group and decreased CEA was significantly associated with high T2 values (T2 value = 34.6 + 3.6 × [osteonecrosis] - 0.14 × CEA, R(2) = 0.52, P = 0.003). CONCLUSION: Degeneration of articular cartilage was associated with osteonecrosis of the femoral head in SLE patients and acetabular dysplasia.

In vivo 3-dimensional analysis of scapular kinematics: comparison of dominant and nondominant shoulders.

BACKGROUND: Alterations in scapular motion frequently are seen in association with various shoulder disorders. It is common clinically to compare the pathological shoulder with the contralateral shoulder, in spite of arm dominance, to characterize the disorder. However, there have been few articles that test the underlying assumption that dominant and nondominant shoulders exhibit comparable dynamic kinematics. The purpose of this study was to compare the 3-dimensional (3-D) scapular kinematics of dominant and nondominant shoulders during dynamic scapular plane elevation using 3-D-2-D (2-dimensional) registration techniques. MATERIALS AND METHODS: Twelve healthy males with a mean age of 32 years (range, 27-36) were enrolled in this study. Bilateral fluoroscopic images during scapular plane elevation and lowering were taken, and CT-derived 3-D bone models were matched with the silhouette of the bones in the fluoroscopic images using 3-D-2-D registration techniques. Angular values of the scapula and scapulohumeral rhythm were compared between dominant and nondominant shoulders with statistical analysis. RESULTS: There was a significant difference in upward rotation angles between paired shoulders (P < .001), while significant differences were not found in the other angular values and scapulohumeral rhythm. The dominant scapulae were 10° more downwardly rotated at rest and 4° more upwardly rotated during elevation compared to the nondominant scapulae. DISCUSSION/CONCLUSION: Scapular motion was not the same between dominant and nondominant arms in healthy subjects. The dominant scapula was rotated further downward at rest and reached greater upward rotation with abduction. These differences should be considered in clinical assessment of shoulder pathology.

Comparison of MRI-based assessment systems for osteoarthritic knees: the irregularity index system and WORMS.

PURPOSE: Several MRI-based evaluation systems for osteoarthritis (OA) of the knee have been developed. Among them the whole-organ magnetic resonance imaging score (WORMS), which evaluates the status of the entire knee joint, appears to be representative. We developed an irregularity index system to measure irregularities of the contours of the femoral condyle on MRI. Only the contour of the condyle was assessed by the irregularity index, whereas several items comprising the knee joint were taken into account by WORMS. This study compared the irregularity index and WORMS in terms of their correlations with clinical scores. METHODS: Thirty-one medial-type OA knees were studied. Kellgren-Lawrence grading was used for X-ray grading: 8 were grade II, 11 were grade III, and 12 were grade IV. Japanese Orthopaedic Association scores and Japanese knee osteoarthritis measure scores were used for clinical assessments. We determined the correlations between MRI-based assessment scores and clinical scores. RESULTS: Both the irregularity index and WORMS exhibited positive correlations with these clinical scores. The irregularity index was associated with bone cysts of the medial compartment and menisci in the articular features of WORMS. CONCLUSIONS: These MRI-based methods are useful for evaluating OA severity. However, the irregularity index may have advantages over WORMS because of its semi-automatic features.

Is a portable accelerometer-based navigation system useful in total hip arthroplasty?: A systematic review and meta-analysis.

BACKGROUND: Precise implant alignment is a crucial prognostic factor for successful outcomes following total hip arthroplasty (THA). A portable accelerometer-based navigation (PN) device may achieve the same accuracy as that achieved by the computer-assisted navigation surgery technique, with the convenience of a conventional technique. Although the usefulness of PN in THA (PN-THA) has been reported, whether it is more accurate than performing THA with a conventional technique (CON-THA) remains controversial. The difference in surgical time between PN-THA and CON-THA is also unclear. Therefore, we conducted a systematic review and meta-analysis of studies comparing results of PN-THA with those of CON-THA. We focused on the following question: is PN-THA superior to CON-THA in terms of radiological parameters and surgical time? PATIENTS AND METHODS: A literature search was conducted in PubMed, Web of Science, and Cochrane Library, to identify studies that met the following inclusion criteria: randomised controlled trials (RCT) or non-RCT, studies involving patients who underwent PN-THA and patients who underwent CON-THA, studies including data on radiological parameters and surgical outcomes. Author names, publication year, country, study design, surgical approach, demographic characteristics of the participants (diagnosis, gender, age, and body mass index), and surgical outcomes (the radiological parameters and the surgical time) were extracted. We calculated the mean differences (MDs) for continuous data with 95% confidence intervals (CIs) for each outcome. p<0.05 was considered significant. RESULTS: Three studies were included in this meta-analysis. The meta-analysis showed that absolute deviation of the postoperative measured angles from the target position for the cup anteversion was significantly smaller in PN-THA than in CON-THA (MD=-1.70, 95% CI=-2.91 to -0.50, [p=0.005]). There was no significant difference in the absolute deviation of the postoperative measured angles from the target position for cup abduction between the groups (MD=-1.82, 95% CI=-4.32-0.67, [p=0.15]). The surgical time was significantly longer in PN-THA than in CON-THA (MD=8.58, 95% CI=4.05-13.10, [p=0.0002]). DISCUSSION: This systematic review and meta-analysis of studies comparing the results of PN-THA with those of CON-THA showed that the PN-THA is advantageous for precise cup implantation compared to CON-THA, although PN-THA has a longer surgical time compared to CON-THA. LEVEL OF EVIDENCE: III.

Characteristics of stepladder fall injuries: a retrospective study.

BACKGROUND: Stepladders are used to work at heights in daily life, but their structure and usage differs from that of a ladder; stepladders can fold and stand without support, whereas ladders cannot fold and, thus, require support from other objects. We hypothesised that this difference made ladder and stepladder fall injuries to differ in characteristics. To clarify this hypothesis, we performed a retrospective cohort study on the stepladder fall injuries and compared their characteristics with that of ladder fall injuries. MATERIALS AND METHODS: We conducted a retrospective cohort study of injuries sustained from either ladder or stepladder falls. In this study, data were retrieved from the computerised database of Teikyo University Chiba Medical Center. Patients admitted to the orthopaedic department because of injury from ladder or stepladder fall were included. The following data were retrieved from the patient records: sex, age, height, body weight, body mass index (BMI), injury severity score (ISS), season, number of injury sites, details of injury and treatment option. RESULTS: One hundred thirty-two patients were included in this study. 101 patients were injured from stepladder falls, and 31 patients were injured from ladder falls. The number of females sustaining injuries due to a stepladder fall was significantly higher than those due to a ladder fall. The most frequent type of injury after fall from stepladder was fracture (48.9%), whereas the most frequent type of injury after fall from ladder was contusion/sprain (56.4%). The most frequently injured body part from stepladder fall was lower extremity (32.6%). In contrast, the most frequently injured body part due to a ladder fall was spine (27.3%). CONCLUSION: The current study found that the number of females sustaining injuries due to a stepladder fall was significantly higher than those due to a ladder fall. Furthermore, the most frequent body parts that needed surgery following a ladder fall injury were spine and upper extremity, whereas the most frequent body parts that needed surgery following a stepladder fall injury was lower extremity. Our study indicated that stepladder falls cause severe injuries and physical disability and can be a huge financial burden.

Objective assessments of medial osteoarthritic knee severity by MRI: new computer software to evaluate femoral condyle contours.

An irregular contour of the medial femoral condyle (MFC) on magnetic resonance imaging (MRI) appears to indicate the severity of medial-type knee osteoarthritis (OA). The purpose of this study was to establish a system to enable objective assessments of OA knee severity using newly developed software that semi-automatically measures irregularity of the MFC. (1) We evaluated 48 patients aged 50-83 years with 55 knees of medial-type OA. The following scores were recorded: Lysholm score, visual analogue scale (VAS) and the Japanese Knee Osteoarthritis Measure (JKOM). MFC irregularity was automatically calculated by newly programmed computer software. Four parameters for condyle irregularity were calculated: (a) the average thickness of the contour (ATC), (b) the ratio of the upper surface length to the lower surface length of the contour (RUL), (c) average squared thickness of the contour (ASTC) and (d) standard deviation of the contour thickness (SDC). (2) Nine knees that underwent total knee arthroplasty were further analysed histopathologically and compared with irregularity score. Statistically, the RUL and SDC were significantly correlated with the Lysholm score, VAS and JKOM, with good reliability. Histological examinations showed that an irregular contour reflected the density of cystic lesions formed in subchondral bone. An irregularity of MFC on MRI is correlated with OA disease severity clinically and histopathologically. The new computer software is useful to objectively assess OA disease severity.

[HIV infected pregnant women in Japan and prevention of mother-to-child transmission].

By the investigation of our study group 595 HIV infected pregnant women have been confirmed in Japan since 1984. In recent years, around 40 pregnant women a year were diagnosed as HIV positive. These HIV infected pregnant women were not concerned with a value of CD4 and received antiretroviral therapy such as zidovudine (AZT) monotherapy or highly active antiretroviral therapy (HAART) starting from the second trimester of pregnancy. According to recommendations and current data, cesarean delivery before the onset of labor is performed around 37 weeks of pregnancy and prophylactic AZT syrups are given to infants starting 8-12 hrs after birth for 6 weeks. These preventive managements such as antiretroviral therapy, elective cesarean delivery and formula feeding significantly reduced mother-to-child transmission (MTCT) of HIV. The transmission rate of HIV fell to 0.5% in Japan, but the problem of the teratogenicity of antiretroviral drugs remain unclear. Further studies are needed.

A new closed reduction technique using a traction table to treat a traumatic posterior dislocation of the hip joint.

Traumatic hip dislocations should be reduced gently and promptly to prevent complications such as osteonecrosis of the femoral head, heterotopic ossification, incomplete recovery of sciatic nerve injury, and fractures of the femoral neck. Many closed reduction manoeuvres have been reported; however, these manoeuvres require forceful and sustained traction, which places an enormous physical burden on surgeons. The aim of the present technical note is to describe a new reduction manoeuvre that uses a traction table to decrease the physical burden experienced by surgeons.

[Progress of research in osteoarthritis. Quantitative magnetic resonance imaging of cartilage in knee osteoarthritis].

Degeneration of the articular cartilage is often observed in patients with knee osteoarthritis. In recent years, several qualitative MR imaging techniques that evaluate deterioration of biochemical components in articular cartilage have been developed. Delayed gadolinium-enhanced MR imaging of cartilage (dGEMRIC) is an MR imaging technique that can evaluate the glycosaminoglycan (GAG) concentrations in articular cartilage. While T2 (transverse relaxation time) mapping is an MR imaging technique that can evaluate the hydration and collagen fiber integrity in articular cartilage. dGEMRIC and T2 mapping can provide useful noninvasive evaluations of cartilage matrix status, and they can be useful for the detection of knee osteoarthritis at earlier stages.

No definite advantage of a portable accelerometer-based navigation system over conventional technique in total knee arthroplasty: A systematic review and meta-analysis.

BACKGROUND: Precise implant alignment is a crucial prognostic factor in total knee arthroplasty (TKA). Portable navigation systems (PN-TKA) were reported to be better than the conventional technique (CON-TKA). We hypothesized that PN-TKA offered greater radiologic precision than CON-TKA in mechanically aligning components. We investigated whether (1) it improved global mechanical alignment, and (2) optimized component placement with respect to the tibial and femoral mechanical axes. PATIENTS AND METHODS: A systematic literature review compared PN-TKA versus CON-TKA. PubMed, Web of Science and Cochrane Library search retrieved ten studies. Their data were pooled using RevMan 5.3. Odds ratios (OR) for dichotomous data were calculated with 95% confidence intervals (CIs) for each outcome. Statistical heterogeneity was assessed as I2 using a standard χ2 test. I2>50% denoted significant heterogeneity requiring a random effects model; otherwise, a fixed effects model was applied. RESULTS: There were significantly fewer outliers for mechanical axis (I2=24%, OR=0.62, 95% CI=0.42-0.91, p=0.02) and coronal femoral component angle (I2=58%, OR=0.31, 95% CI=0.13-0.73, p=0.007) using PN-TKA; however, no significant difference was observed for coronal tibial component angle outliers (I2=0%, OR=0.66, 95% CI=0.38-1.15, p=0.14). DISCUSSION: Although PN-TKA appeared to improve global alignment, it had no effect on coronal tibial alignment, which is a key factor in predicting the long-term success of component fixation. There thus appeared to be no definite advantage of PN-TKA over CON-TKA. LEVEL OF EVIDENCE: III.