Development of an alginate-chitosan biopolymer composite with dECM bioink additive for organ-on-a-chip articular cartilage.

In vitro use of articular cartilage on an organ-on-a-chip (OOAC) via microfluidics is challenging owing to the dense extracellular matrix (ECM) composed of numerous protein moieties and few chondrocytes, which has limited proliferation potential and microscale translation. Hence, this study proposes a novel approach for using a combination of biopolymers and decellularised ECM (dECM) as a bioink additive in the development of scalable OOAC using a microfluidic platform. The bioink was tested with native chondrocytes and mesenchymal stem cell-induced chondrocytes using biopolymers of alginate and chitosan composite hydrogels. Two-dimensional (2D) and three-dimensional (3D) biomimetic tissue construction approaches have been used to characterise the morphology and cellular marker expression (by histology and confocal laser scanning microscopy), viability (cell viability dye using flow cytometry), and genotypic expression of ECM-specific markers (by quantitative PCR). The results demonstrated that the bioink had a significant impact on the increase in phenotypic and genotypic expression, with a statistical significance level of p < 0.05 according to Student's t-test. The use of a cell-laden biopolymer as a bioink optimised the niche conditions for obtaining hyaline-type cartilage under culture conditions, paving the way for testing mechano-responsive properties and translating these findings to a cartilage-on-a-chip microfluidics system.

Minimal clinically important difference of commonly used patient-reported outcome measures in total knee arthroplasty: review of terminologies, methods and proposed values.

PURPOSE: The aim of this article was to highlight various terminologies and methods of calculation of minimal clinically important difference (MCID) and summarize MCID values of frequently used patient-reported outcome measures (PROMs) evaluating total knee arthroplasty (TKA). MATERIALS AND METHODS: PubMed and EMBASE databases were searched through May 2019. Of 71 articles identified, 18 articles matched and underwent a comprehensive analysis for terminologies used to indicate clinical significance, method of calculation, and reported MCID values. RESULTS: MCID was the most common terminology (67% studies) and anchor-based methods were most commonly employed (67% studies) to calculate it. The analytical methods used to calculate and the estimated values of MCID for clinical use are highly variable. MCID values reported for WOMAC scores are 20.5 to 36.0, 17.6 to 33.0 and 12.9 to 25.0 for pain, function and stiffness sub-scales, respectively, and 4.7 to 10.0 for OKS. CONCLUSION: There was lack of standardization in the methodology employed to calculate MCID in the available studies. MCID values reported in this review could be used for patients undergoing TKA, although caution is advised in their interpretation and application.

Coronal Alignment of the Lower Extremity: A Gender-Based Radio-Graphic Analysis in Indian Patients.

BACKGROUND: Variation in the shape of the femur and tibia has been shown to influence hip-kneeankle-axis angle (HKAA) and bears a role in reconstructive surgeries such as total knee arthroplasty (TKA). However, data on the axial alignment of the lower extremity specific to sex largely remains unavailable. Thus, we conducted a study with an aim to measure alignment and calculate differences in both the sexes in Indian population. MATERIALS AND METHODS: The following radiological parameters were measured from weight-bearing long leg radiographs of 966 limbs of Indian subjects via a morphometric software (Matlab R2009a) (1) Hip-Knee-Ankle angle (HKAA), (2) femoral bowing, (3) tibial bowing, (4) condylar plateau angle (CPA). The knees were classified according to the Kellegren and Lawrence grading and the differences between both the sexes were calculated with appropriate statistical tests. RESULTS: 56.04% of the subjects were female. An increase in the mean age was observed for both the genders with an increase in the severity of OA. Height did not show any significant association with the alignment of the limb. The mean HKAA observed was - 5.88° ± 0.35° in females and - 4.99° ± 0.41° in males. The overall mean femoral bow and tibial bow was - 1.26° ± 0.24°, - 1.60° ± 0.18° in females and - 1.09 ± 0.28, - 1.47° ± 0.21° in males. The mean condylar plateau angle was higher in females - 2.67 ± 0.34 as compared to males - 2.35° ± 0.39°. A greater lateral bow was seen in males at higher grades of OA for femur and at lower grades of OA for tibia. CONCLUSION: This study provides gender-based differences in the various axial radio-graphic parameters in a long leg radio-graphs in Indian population which might help in a better understanding of the etiopathogenesis of osteoarthritis and also help planning and execution of reconstructive surgeries such as TKA.

Ultrastructural characterization of cells in the tibial stump of ruptured human anterior cruciate ligament, their changes and significance with duration of injury.

Fibroblasts and myofibroblasts have been known to be present in both ruptured and intact human anterior cruciate ligament (ACL), and although their relevant histology and immunochemistry have been studied in the past, ultrastructural features of these cells are largely lacking. Therefore, we aim to characterise the ultrastructural details of these cells with the help of transmission electron microscopy (TEM) and to study the changes and their significance with duration of injury. Samples from 60 ruptured human ACL undergoing surgery were obtained and categorised according to duration of injury and observed under TEM with main focus on the following ultrastructural features: cellular morphology, presence of rough endoplasmic reticulum, Golgi apparatus, lamina, myofilaments, and presence of myofibroblasts. These features were further correlated with the duration of injury and association, if any, determined using appropriate statistical analysis. A total of 54 male and 6 female patients with mean duration of the injury of 23.01 ± 26.09 weeks (2-108 weeks) were included in the study and categorised into five groups based on duration of injury as follows: I (< 6 weeks), II (7-12 weeks), III (13-20 weeks), IV (21-50 weeks) and V (> 50 weeks). There was a significant association between the above-mentioned ultrastructural features and the duration of injury (p < 0.05) except for the presence of ovoid fibroblast cells (p = 0.53). Furthermore, number of myofibroblasts and cells with Golgi apparatus and rough endoplasmic reticulum was seen to peak at 13-20 weeks following injury. We describe ultrastructural features of fibroblast of different morphology along with myofibroblasts in the ligaments following injury, the changes in which might have a potential bearing on ligament healing.

Combined Olecranon Osteotomy and the Posterior Minimal Invasive Plate Osteosynthesis Approach for a Concomitant Injury of the Humeral Shaft and a Distal Intraarticular Humerus Fracture.

A complex fracture involving the distal humerus is a difficult fracture to treat and more so when it is involved with the ipsilateral shaft of the humerus. Open reduction and internal fixation of the humeral shaft with articular reconstruction have been described for a successful outcome of these complex fractures. However, it has drawbacks, especially in terms of soft tissue dissection and subsequent scarring and non-union. A 42-year-old female presented to the emergency department with a fracture of the intercondylar humerus with an ipsilateral shaft of the left humerus. Combined olecranon osteotomy with posterior minimal plate osteosynthesis was used to treat this fracture. At the one-year follow-up at the postoperative fracture clinic, there was no pain, the range of motion (ROM) of the elbow was 10 degrees to 140 degrees and the radiograph showed a healed fracture with the implant in situ. We present and review a novel technique to treat complex humerus fractures. Articular fragments can be directly visualized and fixed simultaneously. This approach allows for the biological fixation of the fracture and forms a reliable option for treating such complex fractures.