More histologic and ultrastructural degenerative signs in the subscapularis tendon and the joint capsule in male patients with shoulder impingement

New strategies for sterilization and preservation of fresh fish skin grafts

The introduction of fish skin as a biological dressing for treating burns and wounds holds great promise, offering an alternative to existing management strategies. However, the risk of disease transmission is a significant concern. Therefore, this study aimed to examine how established sterilization and preservation procedures affected fish skin grafts' microbiological and histological properties for long-term usage. Lyophilization of the fish skin graft followed by rehydration in normal saline for 15 min did not change the collagen content. Furthermore, gamma irradiation of the lyophilized fish skin graft at different lengths 5, 10, and 25 KGy showed a significant reduction in microbial growth (aerobic bacteria, aerobic yeasts, and fungi) at 15- and 30 days after the irradiation. However, exposure to 10 KGy was found to be the most effective intensity among the different gamma irradiation lengths since it preserved the collagen fiber content and intensity in the lyophilized fish skin grafts at 15- and 30 days after the irradiation. These findings provide efficient preservation and sterilization methods for long-term usage of the fresh Tilapia skin grafts used for biological dressings.

Effectiveness of lyophilized growth factors injection for subacromial impingement syndrome: a prospective randomized double-blind placebo-controlled study

BACKGROUND

Platelet-derived lyophilized growth factors (L-GFs) use a standardized number of allogenic pathogen-free platelets instead of autologous platelets used in PRP as a source of growth factors. This study aimed to evaluate the efficacy of L-GF injection versus placebo in subacromial impingement (SIS) treatment.

METHODS

The current randomized double-blind placebo-controlled study included sixty patients (40 females and 20 males, aged between 24 and 75 years) diagnosed with SIS (both clinically and sonographically). Patients were randomly assigned to two equal groups. Under ultrasound guidance, group 1 received subacromial saline injection, and group 2 received L-GF injection. Clinical examination, pain visual analogue scale (VAS), shoulder pain and disability index (SPADI) and shoulder ultrasound were performed before and at the 8th week after injection.

RESULTS

Follow-up assessment showed statistically significant improvement in the L-GF group regarding active flexion, active and passive internal rotation and extension, SPADI-disability scale, VAS and thickness of the supraspinatus tendon by US. Regression analysis showed that group 1 was approximately 30 times more likely than the L-GF group to experience painful arc at follow-up. Both groups showed statistically significant improvement in SPADI-pain scale and SPADI-total, flexion and abduction (still the mean value of abduction was significantly higher in the L-GF group).

CONCLUSIONS

L-GF injection resulted in clinically significant reductions in pain and functional disability outcomes in patients with SIS. An objective significant reduction in the thickness of the supraspinatus tendon, measured by ultrasound, in the L-GF group hopefully encourages proper healing and functioning in SIS.

TRIAL REGISTRATION

The identification number is NCT04330027, date of first registration (01/04/2020). Unique on 21/11/2019, Protocol ID: 0106178.

The optimal concentration of silver nanoparticles in sterilizing fish skin grafts

Collagen integrity should be considered on using a sterilizing agent for fish skin grafts. This study defined the optimal concentration of silver nanoparticles (Ag NPs) for sterilization of fish skin grafts without disrupting collagen content based on microbiological and histological evaluation. Strips of tilapia skin (n = 5) were randomly allocated to be immersed in Ag NPs solution at different concentrations of 25, 50, 100, and 250 µg/mL, respectively, for 5 min. The treated skin strips underwent bacteriological and histological evaluation. Yeast and fungi were more sensitive to Ag NPs than bacteria. On increasing the nanoparticles concentration, the total counts of aerobic bacteria decrease giving 933.3 ± 28.67, 601 ± 27.66, 288 ± 16.8, 15 ± 4.08 (CFU/cm² ± S.D) at 25, 50, 100, and 250 µg/mL, respectively, comparing with untreated sample (1453.3 ± 57.92). Yeasts and filamentous fungi also exhibited a similar response, achieving a complete inhibition at 100 and 250 µg/mL. Bacillus cereus and Escherichia coli were the dominant aerobic bacteria, Candida albicans and Rhodotorula glutinis were the dominant aerobic yeasts, whereas Aspergillus niger, Aspergillus fumigatus, and Rhizopus stolonifer were the dominant aerobic fungi. The collagen fibers were loose with a wavey pattern at 25 µg/mL, wavey and slightly disorganized at 50 µg/mL, highly disorganized at 100 µg/mL, and compactly arranged and slightly loose at 250 µg/mL. Ag NPs at a concentration of 250 µg/mL could be considered a reliable and feasible method for the sterilization of fish skin grafts before application on human skin with an effective antimicrobial effect and less disrupting impact on collagen content.

Differentiation Ability of Tendon-Derived Stem Cells and Histological Characteristics of Rotator Cuff Remnant on the Greater Tuberosity Degenerated With Age and Chronicity

PURPOSE

To explore and measure the presence and activity of tendon-derived stem cells (TDSCs), as well as histological changes of rotator cuff remnant by age and chronicity of the rotator cuff tear (RCT).

METHODS

154 patients with a full-thickness tear of supraspinatus and/or infraspinatus tendon were included. 52 qualified remnants of the greater tuberosity were captured through arthroscopy. TDSCs in the remnants were isolated for proliferation ability, basal gene expression, and trilineage differentiation detection. Histological characteristics were evaluated by observation of staining under a light microscope and transmission electron microscopy (TEM). To observe the effect of age, samples were divided into two groups: young (＜60 years old) and old (≥60 years old). For chronicity comparison, samples were divided into three groups: acute group (＜3 months), intermediate group (3-12 months), and chronic group (≥12 months).

RESULTS

Between age groups, the remnants in older patients were found to have lower TDSC proliferation ability (cell counting kit-8 results, old: .5325 ± .050, young: .6623 ± .196; P = .008) and basal expression of aggrecan (.630 ± .239; P = .002) and TGF-β1 (transforming growth factor-β1, .589 ± .326, P = .008), weaker ability of chondrogenic differentiation. Furthermore, the remnant tendons in chronic group was found to have weaker adipogenic and chondrogenic differentiation ability of TDSCs, lower tendon degenerative score (acute: 3.57 ± 1.902, intermediate: 5.94 ± 2.313, chronic: 6.86 ± 2.193; P = .023), increased type III collagen region ratio in insertion area (acute: 86.10% ± 8.29%, intermediate: 94.06% ± 5.36%, chronic: 98.90% ± .49%; P = .023), and larger fibril diameters.

CONCLUSION

Differentiation ability of TDSCs derived from the rotator cuff remnant was reduced with age and chronicity. Histological degeneration of remnant tendon deteriorated with chronicity. Remnant in the greater tuberosity was still alive, but those in young or acute injury patients were more active after full-thickness RCT.

CLINICAL RELEVANCE

TDSCs exist in rotator cuff remnant on the greater tuberosity and have multilineage differentiation ability. But the remnant degenerated with age and chronicity.

Increased levels of inflammatory markers in the subscapularis tendon and joint capsule in patients with subacromial impingement

PURPOSE

To analyze biopsy samples from the subscapularis tendon and from the joint capsule from male patients with subacromial impingement syndrome and compare them with samples from male patients with post-traumatic recurrent shoulder instability, to detect increased inflammatory activity that might be present inside the humeroscapular joint.

METHODS

Twenty male patients scheduled for surgery for either subacromial decompression or Bankart reconstruction were included. Four biopsies from each patient were obtained during surgery from the capsule and the subscapularis tendon. Each specimen was analyzed for TNF-α, IL-6, CD-3 and CD-72. Multiplex fluorescence immunohistochemistry was performed on histological samples from the capsule and tendon to demonstrate the level of inflammatory markers. Fluorescence microscope images were acquired using an automated scanning system. On each slide, the number of pixels was registered and used in the analyses.

RESULTS

The subacromial impingement syndrome group comprised eight patients, median age 53 (45-74) years, while the instability group 12, median age 27 (22-48) years (p < 0.00001). The amount of IL-6 and TNF-α was significantly higher in the subscapularis tendon of the patients with subacromial impingement syndrome compared with instability patients (p = 0.0015 and p = 0.0008 respectively). In the capsular samples, significantly higher amount of TNF-α and CD-72 was found in patients with subacromial impingement syndrome compared with instability patients (p < 0.0001 for both). On the other hand, the amount of CD-3 was significantly higher in the instability group (p = 0.0013).

CONCLUSIONS

This study provides evidence that an extended inflammatory process is present, not only in the subacromial bursa but also in the glenohumeral joint in patients with subacromial impingement syndrome.

LEVEL OF EVIDENCE

Level III.

CLINICAL RELEVANCE

To develop a treatment targeted towards intra-articular inflammatory cytokines appears appealing.

No significant histological or ultrastructural tendinosis changes in the hamstring tendon in patients with mild to moderate osteoarthritis of the knee?

PURPOSE

To investigate the periarticular degenerative changes of the knee joint in association with osteoarthritis (OA). More tendinosis was expected to be found in the semitendinosus tendon in patients with knee OA than in patients without knee OA.

METHODS

Samples from 41 patients were included between January 2016 and October 2017. Twenty-one patients median age 53 (33-63) years with mild to moderate OA underwent high tibial osteotomy (HTO) and 20 patients median age 38 (31-57) years without OA underwent anterior cruciate ligament reconstruction (ACLR). Biopsies from the semitendinosus tendon were obtained at the time of surgery and examined histologically, morphologically and ultrastructurally using light and electron microscope.

RESULTS

The histological evaluation of the semitendinosus tendon revealed the presence of more hemosiderin in the ACLR group. No significant morphological or ultrastructural differences were shown between patients in the HTO and ACLR group.

CONCLUSION

Patients with mild and moderate medial compartment knee OA displayed no more degenerative changes in their semitendinosus tendon than patients without OA, as seen in both the light and the electron microscope.

LEVEL OF EVIDENCE

III.

Validation of Three Different Sterilization Methods of Tilapia Skin Dressing: Impact on Microbiological Enumeration and Collagen Content

Tilapia fish skin has demonstrated promise as a stable and practical biological dressing to be used in wound and burn management. However, the appropriate sterilization technique of the Tilapia fish skin is crucial before its clinical application. The standard sterilization technique must eliminate harmful pathogens but maintain the structural and biochemical properties that could compromise the dressing function. This study investigated and compared the efficiency of three sterilizing agents; chlorhexidine gluconate 4% (CHG), povidone iodine 10% (PVP-I), and silver nanoparticles (25 μg/mL) (AgNPs), at three different times (5, 10, and 15 min) on Tilapia fish skin based on the microbial count, histological and collagen properties. Among the sterilization procedures, AgNPs showed rapid and complete antimicrobial activity, with a 100% reduction in microbial growth of the fish skin throughout the treated times. Furthermore, AgNPs did not impair the cellular structure or collagen fibers content of the fish skin. However, CHG and PVP-I caused alterations in the collagen content. This study demonstrated that the AgNPs treatment of Tilapia fish skin provided sterile skin while preserving the histological properties and structural integrity. These findings provide an efficient and quick sterilization method suitable for Tilapia fish skin that could be adopted as a biological dressing.

Radiofrequency microtenotomy: a promising method for treatment of rotator cuff tendinopathy

PURPOSE

Subacromial pain syndrome is a common disorder. Arthroscopic subacromial decompression is currently the preferred treatment method. Bipolar radiofrequency microtenotomy has shown promising results in treating tendinosis. In this study, the authors compare the results after arthroscopic acromioplasty with bipolar radiofrequency microtenotomy for patients with subacromial pain syndrome.

METHODS

A total of 27 patients, with subacromial pain syndrome, were followed for 2 years. There were 14 patients in the arthroscopic acromioplasty group and 13 patients in the radiofrequency microtenotomy group. Clinical outcome data included pain reported using a visual analog scale, Constant score, and strength. Magnetic resonance imaging of the affected shoulder was performed before and 2 years after intervention for an evaluation of the tendinosis grade.

RESULTS

All patients attended the final follow-up 2 years after intervention. No significant differences were found at baseline between the groups. Pain measured by the visual analog scale revealed a significant reduction in both groups at 12 weeks, 6 months and 2 years compared with baseline. There was no significant difference between the groups in terms of visual analog scale, Constant score, or strength. The magnetic resonance imaging revealed a significant improvement in the tendinosis score in both groups, without any significant difference between the groups.

CONCLUSION

In this prospective randomized study, the clinical assessments revealed a significant improvement in terms of the visual analog scale, strength, Constant score, and tendinosis score 2 years after intervention with either arthroscopic acromioplasty or radiofrequency microtenotomy in patients with subacromial pain syndrome. However, no significant differences were found between the groups. This study reveals that there are surgical options other than acromioplasty in patients with SAPS.

LEVEL OF EVIDENCE

II.

Immunohistochemical features of rotator cuff tendinopathy

BACKGROUND

Rotator cuff tendinopathy is a common musculoskeletal ailment in sedentary and athletic individuals. Various mediators of inflammation have been detected in human tendons: they are thought to initiate or progress the course of tendinopathy.

SOURCES OF DATA

An online search was conducted using AMED, CINAHL, Embase, The Cochrane Library, PEDro and Pubmed, using the terms tendinopathy, tendon, tendinitis, tendinosis, histology, histopathology, immunohistochemistry, immunohistochemical, rotator cuff and pain.

AREAS OF AGREEMENT

Histological examination of tendinopathic tendons shows degeneration of the collagen structure and infiltration of fat and vessels, together with increased expression of inflammatory cytokines, MMP-1, 2, 3, 9, 13, vascular endothelial growth factor and Hypoxia inducible factor (HIF).

AREAS OF CONTROVERSY

Most of the studies about this topic exhibited limited validity because of lack of appropriately matched controls and no inclusion or exclusion criteria. The evidence associated with the histopathological analysis of the rotator cuff is limited.

GROWING POINTS

The histochemical and immunohistochemical features of rotator cuff tendinopathy are still unclear. A thorough understanding of the vascularity, innervation and biochemical mediators of pain could be used to target rotator cuff pathology, and possibly guide the therapy of painful rotator cuff disorders.

AREAS TIMELY FOR DEVELOPING RESEARCH

There is a need for a validated reproducible method of rotator cuff tendon biopsy evaluation. We require further studies with improved designs to effectively evaluate the histological and immunohistochemical features of rotator cuff tendinopathy.