Tuberoplasty reduces resistance force in dynamic shoulder abduction for irreparable rotator cuff tears: a cadaveric biomechanical study.

BACKGROUND: Arthroscopic tuberoplasty is an optional technique for managing irreparable rotator cuff tears. However, there is a lack of studies investigating the resistance force during shoulder abduction in cases of irreparable rotator cuff tears and tuberoplasty. HYPOTHESES: In shoulders with irreparable rotator cuff tears, impingement between the greater tuberosity (GT) and acromion increases the resistance force during dynamic shoulder abduction. Tuberoplasty is hypothesized to reduce this resistance force by mitigating impingement. STUDY DESIGN: Controlled laboratory study. METHODS: Eight cadaveric shoulders, with a mean age of 67.75 years (range, 63-72 years), were utilized. The testing sequence included intact rotator cuff condition, irreparable rotator cuff tears (IRCTs), burnishing tuberoplasty, and prosthesis tuberoplasty. Burnishing tuberoplasty refers to the process wherein osteophytes on the GT are removed using a bur, and the GT is subsequently trimmed to create a rounded surface that maintains continuity with the humeral head. Deltoid forces and actuator distances were recorded. The relationship between deltoid forces and actuator distance was graphically represented in an ascending curve. Data were collected at five points within each motion cycle, corresponding to actuator distances of 20 mm, 30 mm, 40 mm, 50 mm, and 60 mm. RESULTS: In the intact rotator cuff condition, resistance forces at the five points were 34.25 ± 7.73 N, 53.75 ± 7.44 N, 82.50 ± 14.88 N, 136.25 ± 30.21 N, and 203.75 ± 30.68 N. In the IRCT testing cycle, resistance forces were 46.13 ± 7.72 N, 63.75 ± 10.61 N, 101.25 ± 9.91 N, 152.5 ± 21.21 N, and 231.25 ± 40.16 N. Burnishing tuberoplasty resulted in resistance forces of 32.25 ± 3.54 N, 51.25 ± 3.54 N, 75.00 ± 10.69 N, 115.00 ± 10.69 N, and 183.75 ± 25.04 N. Prosthesis tuberoplasty showed resistance forces of 29.88 ± 1.55 N, 49.88 ± 1.36 N, 73.75 ± 7.44 N, 112.50 ± 7.07 N, and 182.50 ± 19.09 N. Both forms of tuberoplasty significantly reduced resistance force compared to IRCTs. Prosthesis tuberoplasty further decreased resistance force due to a smooth surface, although the difference was not significant compared to burnishing tuberoplasty. CONCLUSION: Tuberoplasty effectively reduces resistance force during dynamic shoulder abduction in irreparable rotator cuff tears. Prosthesis tuberoplasty does not offer a significant advantage over burnishing tuberoplasty in reducing resistance force. CLINICAL RELEVANCE: Tuberoplasty has the potential to decrease impingement, subsequently reducing resistance force during dynamic shoulder abduction, which may be beneficial in addressing conditions like pseudoparalysis.

Arthroscopic Resection for Extra-articular Ganglion Cysts of Gastrocnemius Near Vessels.

Extra-articular ganglion cysts arising from the gastrocnemius tendon near popliteal vessels can cause pain and claudication. Open resection of this kind of cyst has been described frequently because the vessels can be well protected with a retractor. However, it's a challenge to remove cysts that are near vessels under arthroscopy, because a retractor cannot be used in arthroscopic surgery. This article will report a method of arthroscopic resection for extra-articular ganglion cysts near popliteal vessels.

A Hybrid Scaffold Induces Chondrogenic Differentiation and Enhances In Vivo Cartilage Regeneration.

Extensively researched tissue engineering strategies involve incorporating cells into suitable biomaterials, offering promising alternatives to boost tissue repair. In this study, a hybrid scaffold, Gel-DCM, which integrates a photoreactive gelatin-hyaluronic acid hydrogel (Gel) with an oriented porous decellularized cartilage matrix (DCM), was designed to facilitate chondrogenic differentiation and cartilage repair. The Gel-DCM exhibited excellent biocompatibility in vitro, promoting favorable survival and growth of human adipose-derived stem cells (hADSCs) and articular chondrocytes (hACs). Gene expression analysis indicated that the hACs expanded within the Gel-DCM exhibited enhanced chondrogenic phenotype. In addition, Gel-DCM promoted chondrogenesis of hADSCs without the supplementation of exogenous growth factors. Following this, in vivo experiments were conducted where empty Gel-DCM or Gel-DCM loaded with hACs/hADSCs were used and implanted to repair osteochondral defects in a rat model. In the control group, no implants were delivered to the injury site. Interestingly, macroscopic, histological, and microcomputed tomography scanning results revealed superior cartilage restoration and subchondral bone reconstruction in the empty Gel-DCM group compared with the control group. Moreover, both hACs-loaded and hADSCs-loaded Gel-DCM implants exhibited superior repair of hyaline cartilage and successful reconstruction of subchondral bone, whereas defects in the control groups were predominantly filled with fibrous tissue. These observations suggest that the Gel-DCM can provide an appropriate three-dimensional chondrogenic microenvironment, and its combination with reparative cell sources, ACs or ADSCs, holds great potential for facilitating cartilage regeneration.

Analysis of differentially expressed genes in torn rotator cuff tendon tissues in diabetic patients through RNA-sequencing.

BACKGROUND: Rotator cuff tears (RCT) is a common musculoskeletal disorder in the shoulder which cause pain and functional disability. Diabetes mellitus (DM) is characterized by impaired ability of producing or responding to insulin and has been reported to act as a risk factor of the progression of rotator cuff tendinopathy and tear. Long non-coding RNAs (lncRNAs) are involved in the development of various diseases, but little is known about their potential roles involved in RCT of diabetic patients. METHODS: RNA-Sequencing (RNA-Seq) was used in this study to profile differentially expressed lncRNAs and mRNAs in RCT samples between 3 diabetic and 3 nondiabetic patients. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis were performed to annotate the function of the differentially expressed genes (DEGs). LncRNA-mRNA co-expression network and competing endogenous RNA (ceRNA) network were constructed to elucidate the potential molecular mechanisms of DM affecting RCT. RESULTS: In total, 505 lncRNAs and 388 mRNAs were detected to be differentially expressed in RCT samples between diabetic and nondiabetic patients. GO functional analysis indicated that related lncRNAs and mRNAs were involved in metabolic process, immune system process and others. KEGG pathway analysis indicated that related mRNAs were involved in ferroptosis, PI3K-Akt signaling pathway, Wnt signaling pathway, JAK-STAT signaling pathway and IL-17 signaling pathway and others. LncRNA-mRNA co-expression network was constructed, and ceRNA network showed the interaction of differentially expressed RNAs, comprising 5 lncRNAs, 2 mRNAs, and 142 miRNAs. TF regulation analysis revealed that STAT affected the progression of RCT by regulating the apoptosis pathway in diabetic patients. CONCLUSIONS: We preliminarily dissected the differential expression profile of lncRNAs and mRNAs in torn rotator cuff tendon between diabetic and nondiabetic patients. And the bioinformatic analysis suggested some important RNAs and signaling pathways regarding inflammation and apoptosis were involved in diabetic RCT. Our findings offer a new perspective on the association between DM and progression of RCT.