Total Knee Arthroplasty in Patients with Unsuspected Tuberculosis of the Joint: A Report of Four Cases and a Systematic Review of the Literature.

OBJECTIVES: To provide a case series and systematic review that explores the clinical manifestations, treatments, and methods for defining tuberculosis diagnoses in patients who have undergone total knee arthroplasty (TKA). METHODS: Four patients (three women, one man; average age, 59.5 ± 8.89 years; range, 48-69 years) underwent TKA and were subsequently treated for previously unsuspected knee tuberculosis between January 2013 and December 2019. We also reviewed published cases of tuberculous periprosthetic joint infections (TBPJIs) following TKA through databases of MEDLINE/PubMed, the Cochrane Library, and EMBASE. We reviewed studies that were published between January 1980 and December 2019. RESULTS: In our four cases, the preoperative diagnoses were osteoarthritis (n = 2), rheumatoid arthritis (one case), and Charcot's arthropathy (one case). The main clinical manifestations were knee swelling and pain, without fever, weakness, or weight loss. Comorbidities included multiple joints with rheumatoid arthritis or Charcot's arthropathy, diabetes mellitus, and uremia. One patient had a history of lumbar tuberculosis treated with debridement and intervertebral fusion. Preoperative elevated erythrocyte sedimentation rates (ESRs) were detected in all cases, and elevated C-reactive protein (CRP) levels were observed in three cases. The tuberculosis diagnoses were confirmed via histopathologic analysis (three cases) and second-generation sequencing (one case). Three patients received antituberculosis therapy for 1 year, without surgical intervention. Two-stage exchange arthroplasty was performed in one patient because of prosthesis loosening. Within an average follow-up period of 24.75 months, tuberculosis reactivation was not observed and overall functional improvement was demonstrated. Forty-four TBPJI cases were reported in the literature between January 1980 and December 2019. Most (59.09%) occurred within the first year after the index arthroplasty, and the diagnoses were confirmed by culturing Mycobacterium tuberculosis in 88.64% of cases. Favorable outcomes were achieved in 90.91% of the patients who did not undergo surgery, 71.43% of those treated with debridement, 93.33% undergoing revision arthroplasty, and in 90.91% of those undergoing resection and arthrodesis. CONCLUSIONS: Clinical manifestations of knee tuberculosis and TBPJI are atypical. Thus, attention should be paid to finding the causes of increased ESRs and CRP levels, particularly in patients with weakened immune functioning, before performing TKA. Pathological examination is an effective method for diagnosing tuberculosis, although sending multiple specimens for pathological examination is necessary.

Comprehensive metabolomic, proteomic and physiological analyses of grain yield reduction in rice under abrupt drought-flood alternation stress.

Abrupt drought-flood alternation (T1) is a meteorological disaster that frequently occurs during summer in southern China and the Yangtze river basin, often causing a significant loss of rice production. In this study, the response mechanism of yield decline under abrupt drought-flood alternation stress at the panicle differentiation stage was analyzed by looking at the metabolome, proteome as well as yield and physiological and biochemical indexes. The results showed that drought and flood stress caused a decrease in the yield of rice at the panicle differentiation stage, and abrupt drought-flood alternation stress created a synergistic effect for the reduction of yield. The main reason for the decrease of yield per plant under abrupt drought-flood alternation was the decrease of seed setting rate. Compared with CK0 (no drought and no flood), the net photosynthetic rate and soluble sugar content of T1 decreased significantly and its hydrogen peroxidase, superoxide dismutase, peroxidase activity increased significantly. The identified differential metabolites and differentially expressed proteins indicated that photosynthesis metabolism, energy metabolism pathway and reactive oxygen species response have changed strongly under abrupt drought-flood alteration stress, which are factors that leads to the rice grain yield reduction.

Comparative study of callus progression in limb lengthening with or without intramedullary nail with reference to the pixel value ratio and the Ru Li's classification.

INTRODUCTION: Callus progression is a great concern during limb lengthening. In this study, we investigated the difference in callus progression between tibial lengthenings with and without intramedullary nail. METHOD: Seventy tibiae in 38 patients with an average age of 24 years were lengthened with Ilizarov external fixator and nail; 56 tibiae in 40 patients with an average age of 28.6 years were lengthened with the same Ilizarov external fixator but without nail. The callus progression was compared with reference to pixel value ratio (PVR) and Ru Li's classification. Statistical analysis was performed to compare the variation trend of PVR and incidence of various callus pathways (particular patterns of callus progression as outlined in Ru Li's classification) and shapes of each aspect of callus between the two groups. RESULTS: The trend of PVR was not statistically different in posterior, lateral and medial aspects of the callus between the two groups, but averagely lower in the anterior aspect in the group without nail than that with nail. The group without nail presented less incidence of homogeneous pathway, greater incidence of heterogeneous pathway; also greater incidence of fusiform callus, less incidence of cylindrical callus. CONCLUSION: It was concluded that with nail, the callus underwent a more favorable progression and even longer lengthening could be allowed.

Comparison of bone age delay and recovery in Meyer dysplasia and Legg-Calvé-Perthes disease: a pilot study.

BACKGROUND: Meyer dysplasia (MD) is a rare disease but readily mistaken for Legg-Calvé-Perthes disease (LCPD). Although most published studies on MD have characterized and differentiated it from LCPD radiologically and clinically, differences with regard to bone age delay and recovery have not been sought. We deemed it necessary to distinguish bone age delay and recovery patterns between the two entities for better differentiation, prognostication, and parental advice. METHODS: Bone age delay and recovery of eight patients who were initially diagnosed with LCPD but were found to have MD were retrospectively reviewed and compared with those of age-matched patients with LCPD. Based on hand radiographs, the radius-ulna-short bones (RUSs) and carpal bone ages were determined using the Tanner and Whitehouse 3 (TW3) method. Minimum follow-up was 2 years (range 2-5 years). Differences in RUS and carpal bone ages and recovery patterns between the two entities were analyzed using trend lines in scatter plots. RESULTS: The mean delay of RUS bone age was significantly less in MD (0.52 ± 0.87 years) than in LCPD (1.11 ± 0.99 years). However, the difference between the mean carpal bone age delay in MD (1.13 ± 1.28 years) and LCPD (1.47 ± 1.19 years) was not significant. Trend lines showed faster bone age recovery patterns in MD than in LCPD. CONCLUSIONS: Bone age was delayed in both MD and LCPD but was less delayed in the former. RUS bone age showed more significant differences than carpal bone age when comparing the two entities and hence might be more useful for differentiating the two. Earlier bone age recovery patterns may be anticipated in patients with MD.

Injury and regeneration of intramuscular connective tissue subjected to various regimes of distraction.

OBJECTIVE: To investigate the effect on intramuscular connective tissue and passive range of joint motion by the stress produced in limb lengthening. METHODS: An animal model of limb lengthening was established in the tibia of rabbits. Distraction was initiated at a rate of 1 mm/d and 2 mm/d in two steps respectively, and both proceeded until 10% and 20% of the tibia length was achieved. Muscle samples were harvested at the time when distraction ended and at the 4th week of consolidation after the distraction. Scanning electron microscope was applied to observe the morphological changes of the perimysium. The goniometer, which we made for this study, was used to measure the passive range of joint motion. RESULTS: The collagen fibers were partitioned in bundles, crimped and interconnected closely and orderly. In the regime of 1 mm/d distraction with 10% lengthening, no apparent changes of the collagen fiber and passive range of joint motion was demonstrated. When tibia was increased to 20%, the crimped fibers showed a tendency of being straightened while the passive range of joint motion was reduced. The findings remained the same at the 4th week of consolidation. In the regime of 2 mm/d distraction with 10% lengthening, the crimped structure of the collagen fibers in the perimysium disappeared and the fibers were almost straightened. Additionally, the interconnection of the collagen fibers became loosened and interstice was presented among the fibers. At the 4th week of consolidation, the restoration to the original crimped structure was not completed. When the lengthening ratio was increased to 20%, the collagen fibers were straightened completely. This condition remained unchanged throughout all 4 weeks. The passive range of joint motion was reduced dramatically in the regime of 2 mm/d distraction. CONCLUSION: The ultrastructure of perimysium and the passive range of joint motion in the regime of 1mm/d lengthening shows the condition closest to the normal ones. The regime of 2 mm/d lengthening may cause an apparent change in the ultrastructure of perimysium and passive range of joint motion.

[A clinical follow-up study on treatment of adolescent idiopathic scoliosis with brace].

OBJECTIVE: To evaluate clinical outcomes of bracing and analyze related factors that influence curative effects in adolescents with idiopathic scoliosis, and to investigate indications of bracing. METHODS: Seventy-nine patients with AIS who had no history of prior therapy were treated with a brace. Several parameters were consecutive measured and documented during the period of follow-up including Cobb's angles, curve patterns, menarche status, sitting heights, standing heights, Risser sign, apical vertebral rotation, and so on. RESULTS: The average period of followed-up was 30 months (12 months to 60 months). Twenty-one patients (26.6%) presented curve deterioration, 40 patients have no obvious curve change, 18 patients (22.8%) got a curve improvement. There was significantly lower percentage of curve progression and higher percentage of curve improvement in cases with Cobb's angle less than 35 degrees at the first visit (P < 0.05). The percentage of curve progression was significantly greater in the cases with apical vertebral rotation beyond grade III while the percentage of curve improvement was lower (P < 0.05). Curve patterns, Risser sign and other parameters were found to make their effects on the percentage of curve progression and improvement, which, however, was not statistically significant (P > 0.05). CONCLUSION: Bracing can limit or improve mild and moderate curve of idiopathic scoliosis effectively, especially in cases with initial curve magnitude ranging from 20 degrees to 35 degrees . Risser sign is not a reliable parameter for measuring the outcome of bracing treatment for idiopathic scoliosis. Surgery is advised as soon as possible for the cases with initial Cobb's angles greater than 45 degrees and initial apical vertebral rotation beyond grade III early while bracing did not work.

Compositional variation of fibrous callus and joint cartilage in different internal environments.

OBJECTIVE: To evaluate the compositional variation of fibrous callus in the fracture site and the joint cavity and joint cartilage after being transplanted in the muscle pouch. METHODS: Thirty 2 month old New Zealand white rabbits (weighing 1-1.5 kg) were randomly divided into two groups: a callus transplantation group (Group A, n=15) and a cartilage transplantation group (Group B, n=15). In Group A, closed radius fracture was made and the autologous fibrous callus was transplanted in the right knee joint cavity at 12 days postoperatively. In Group B, the right knee joint cartilage of the animals was transplanted in the autologous back muscle pouches under anesthesia. Then all the animals were killed by overdose anesthetic 3 weeks after transplantation. And the transplanted fibrous callus, the healed bones in the fracture sites and the transplanted joint cartilage were obtained for assessment of compositional variation. RESULTS: Pure fibrous composition was found in the callus at the fracture sites in Group A at 12 days postoperatively. And for 11 out of the 15 animals, the fibrous callus was transformed into cartilaginous tissues after 3 weeks of transplantation, but the fibrous callus was absent in the other 4 animals. The fibrous calluses at the original site and the fracture locus were differentiated into bony tissues. Bony tissue transformation was found in the transplanted joint cartilages in the muscle pouch of all the animals in Group B. CONCLUSIONS: The fracture sites or joint cavity may facilitate callus differentiation in different ways: the former is helpful for osteogenesis while the latter for the development and maintenance of cartilages, and the muscle pouch is inclined to induce the osteogenic phenotype for cartilages.

[Capacity evaluation of different media for isolating bacteria populations from the rhizosphere of tomato plants with DGGE].

Bacteria from the rhizosphere of tomato plants were cultured on nutrient broth, YG, soil extract and root exudate media. The capabilities of these 4 media for recovering the bacterium communities were evaluated with denaturing gradient gel electrophoresis (DGGE) technique. Results showed that there were certain differences in the obtained bacterial communities when different media and culture tempitures were applied. Numbers of CFU on solid media indicated that the YG agar medium incubated at 20 degrees C could recover more populations than the high-nutrient-concentration Nutrient agar medium; while the root exudate based medium recovered the highest numbers of bacteria from the rhizosphere of tomato plants. 16S rDNA fragments amplified by PCR from different media and rhizosphere soil bacterium DNA were analyzed with DGGE. The DGGE fingerprints showed that there was a discrepancy between bacterial populations observed by cultivation techniques and molecular retrieval. The rhizosphere pattern consisted of more strong bands than the media. The DGGE patterns of the 4 different media incubated at 28 degrees C showed a relatively high level of similarity. In contrast, those of the 4 media incubated at 20 degrees C were significantly different from each other. Shannon-Wiener index (H), species richness (S), Cs values and Cluster dendrogram analysis of different samples revealed that the YG agar medium and the root exudate based medium recovered the highest proportion of predominant populations from the rhizosphere. In the study a new strategy has been proposed for evaluating the capacity of different media in terms of recovering the predominant populations.