Effects of a viscosupplementation therapy on rabbit menisci in an anterior cruciate ligament transection model of osteoarthritis

Adhesive hydrogels in osteoarthritis: from design to application

Osteoarthritis (OA) is the most common type of degenerative joint disease which affects 7% of the global population and more than 500 million people worldwide. One research frontier is the development of hydrogels for OA treatment, which operate either as functional scaffolds of tissue engineering or as delivery vehicles of functional additives. Both approaches address the big challenge: establishing stable integration of such delivery systems or implants. Adhesive hydrogels provide possible solutions to this challenge. However, few studies have described the current advances in using adhesive hydrogel for OA treatment. This review summarizes the commonly used hydrogels with their adhesion mechanisms and components. Additionally, recognizing that OA is a complex disease involving different biological mechanisms, the bioactive therapeutic strategies are also presented. By presenting the adhesive hydrogels in an interdisciplinary way, including both the fields of chemistry and biology, this review will attempt to provide a comprehensive insight for designing novel bioadhesive systems for OA therapy.

Natural biopolymer scaffold for meniscus tissue engineering

Meniscal injuries caused by trauma, degeneration, osteoarthritis, or other diseases always result in severe joint pain and motor dysfunction. Due to the unique anatomy of the human meniscus, the damaged meniscus lacks the ability to repair itself. Moreover, current clinical treatments for meniscal injuries, including meniscal suturing or resection, have significant limitations and drawbacks. With developments in tissue engineering, biopolymer scaffolds have shown promise in meniscal injury repair. They act as templates for tissue repair and regeneration, interacting with surrounding cells and providing structural support for newly formed meniscal tissue. Biomaterials offer tremendous advantages in terms of biocompatibility, bioactivity, and modifiable mechanical and degradation kinetics. In this study, the preparation and composition of meniscal biopolymer scaffolds, as well as their properties, are summarized. The current status of research and future research prospects for meniscal biopolymer scaffolds are reviewed in terms of collagen, silk, hyaluronic acid, chitosan, and extracellular matrix (ECM) materials. Overall, such a comprehensive summary provides constructive suggestions for the development of meniscal biopolymer scaffolds in tissue engineering.

[Experimental study on crosslinked-chitosan in treatment of knee osteoarthritis in rabbits]

Objective

To study the effect of intraarticular injection of crosslinked-chitosan in the treatment of knee osteoarthritis in rabbits.

Methods

Thirty-two New Zealand white rabbits were randomly divided into 4 groups (groups A, B, C, and D; 8 rabbits in each group). The knee osteoarthritis models were prepared by anterior cruciate ligament transection in the left hind in groups A, B, and C. At 4 weeks after operation, the rabbits were received intraarticular injection of 0.6 mL crosslinked-chitosan in group A, 0.3 mL chitosan (once per 2 weeks, for twice) in group B, and 0.3 mL saline (once per 2 weeks, for twice) in group C. The rabbits in group D were treated with sham operation in the left hind, and received intraarticular injection of 0.3 mL saline (once per 2 weeks, for twice). At 8 weeks, the macroscopic observation, histological examination (HE staining, Safranin-fast green double staining, and Mankin score), scanning electron microscopy (SEM) observation, and immunohistochemical staining of collagen type Ⅱ were performed.

Results

Macroscopic and SEM observations showed that the cartilage in group D was basically the same as normal and better than that in groups A and B, and the abrasion of cartilage in group C was the most serious. The histological observation results in groups A and B were slightly similar and better than those in group C, but not up to the structure of group D. The macroscopic score and Mankin score of groups B and C were significantly higher than those of group D ( P<0.05), and there was no significant difference between group A and group B ( P>0.05). Immunohistochemical staining results showed that the collagen type Ⅱ positive percentage of chondrocytes was significantly higher in group D than that in groups B and C, and no significant difference was found between group A and group B ( P>0.05).

Conclusion

The crosslinked-chitosan can significantly improve the osteoarthritis of the rabbit knee, delay the pathological changes of osteoarthritis, and decrease the frequency of injection.

The long-term effects of hyaluronic acid on hemiplegic shoulder pain and injury in stroke patients: A randomized controlled study

BACKGROUND

Hemiplegic shoulder pain (HSP) is one common complication after stroke. The interferes with the functionality of the affected shoulder in patients with stroke during rehabilitation. Hyaluronic acid (HA) could have positive effects on pain relief and shoulder motion in stroke patients with hemiplegic shoulders. We investigated long-term benefits of HA injection in stroke patients with HSP and rotator cuff injury.

METHODS

A randomized, double-blinded controlled trial was conducted in one medical center. The stroke patients with HSP and rotator cuff injury were randomized and allocated to the control (n = 9) and experimental (n = 18) groups. The control and the experimental groups received ultrasound-guided subacromial 0.9% sodium chloride and HA injections, respectively. All injections were performed once per week for 3 weeks. The associated upper extremity functional assessments, shoulder pain scale, and sonography findings on affected shoulders were measured before interventions and at the 4th and 12th week after local injections.

RESULTS

The visual analog scale (VAS) scores of HSP were significantly reduced in the control and experimental groups at the 4th week following intervention. Additionally, the VAS score at the 12th week was also significantly reduced in the experimental group. Significant differences were found in the hyperemia occurrence in the subscapularis tendon at the 12th week after intervention (P = .018) and in the severity of hyperemia in the long head of the biceps tendon (P = .042) and the subscapularis tendon after intervention (P = .014).

CONCLUSION

Subacromial HA injections might provide longer HSP reduction and decrease in hyperemia reactions at the long head of biceps tendon and subscapularis tendon in stroke patients with HSP and tendon injury.