Distal forearm squeeze test for the diagnosis of digital flexor tendon injuries.

BACKGROUND: The forearm/wrist squeeze/compression test has been used to examine digital flexor tendon injuries with varied names. Furthermore, the test has not been minutely described and its mechanism remains unclear. We renamed the test the "distal forearm squeeze test". The purpose of this study was to elaborate on the test and elucidate the mechanism. METHODS: Two patients with digital flexor tendons ruptured in zone 3 and zone 1 respectively and 50 outpatients with intact digital tendons underwent the test. Then the test was performed on 3 chickens under 4 conditions. First, when the digital flexor and extensor tendons were all intact. Second, after the flexor tendons of the third toe were transected. Third, after the flexor tendons of all toes of the foot were transected. Finally, after the flexor and extensor tendons of all toes of the foot were transected. RESULTS: In the patient with digital flexor tendons ruptured in zone 3, the test showed that the injured digit was flexed slightly while the uninjured digits were flexed obviously. In the patient with digital flexor tendon ruptured in zone 1, after separate stabilization of the proximal interphalangeal (PIP) joints of the injured and uninjured fingers in extension, the test showed that the distal interphalangeal joint of the patient's injured finger had no response, while those of the uninjured fingers were flexed. All 50 subjects showed clenched or half-clenched hands in response to the test. The test showed that all toes were flexed when the digital tendons of the chicken were intact. All toes were flexed except the third toe after the flexor tendons of the third toe were transected. All toes were extended after all the digital flexor tendons were transected. All toes had no response after all the digital flexor and extensor tendons were transected. CONCLUSIONS: The distal forearm squeeze test is valuable in examining digital flexor tendon injuries. If only the flexor digitorum profundus tendon is examined, the PIP joint of the finger should be stabilized in extension during the test.

A configurable method for clinical quality measurement through electronic health records based on openEHR and CQL.

BACKGROUND: One of the primary obstacles to measure clinical quality is the lack of configurable solutions to make computers understand and compute clinical quality indicators. The paper presents a solution that can help clinical staff develop clinical quality measurement more easily and generate the corresponding data reports and visualization by a configurable method based on openEHR and Clinical Quality Language (CQL). METHODS: First, expression logic adopted from CQL was combined with openEHR to express clinical quality indicators. Archetype binding provides the clinical information models used in expression logic, terminology binding makes the medical concepts consistent used in clinical quality artifacts and metadata is regarded as the essential component for sharing and management. Then, a systematic approach was put forward to facilitate the development of clinical quality indicators and the generation of corresponding data reports and visualization. Finally, clinical physicians were invited to test our system and give their opinions. RESULTS: With the combination of openEHR and CQL, 64 indicators from Centers for Medicare & Medicaid Services (CMS) were expressed for verification and a complicated indicator was shown as an example. 68 indicators from 17 different scenes in the local environment were also expressed and computed in our system. A platform was built to support the development of indicators in a unified way. Also, an execution engine can parse and compute these indicators. Based on a clinical data repository (CDR), indicators were used to generate data reports and visualization and shown in a dashboard. CONCLUSION: Our method is capable of expressing clinical quality indicators formally. With the computer-interpretable indicators, a systematic approach can make it more easily to define clinical indicators and generate medical data reports and visualization, and facilitate the adoption of clinical quality measurements.

Extending CQL with openEHR to Express Clinical Quality Indicators.

Clinical Quality Language (CQL), a HL7 authoring language to express clinical quality indicators, provides the capability to express logic that is human readable yet structured enough for processing a query electronically. OpenEHR is a widely used, modeling methodology, but currently CQL cannot support openEHR archetypes which hinders its usage in openEHR environment. This paper presents a method to express and compute clinical quality indicators by extending CQL with openEHR archetypes. To verify the feasibility of this method, 64 indicators from the Centers for Medicare & Medicaid Services (CMS) and 118 indicators from local environment in China were utilized. The results show that those indicators can be well represented and computed in openEHR environment.

The Effect of Remnant Preservation on Tibial Tunnel Enlargement in Anterior Cruciate Ligament Reconstruction with Polyethylene Terephthalate Artificial Ligament in a Large Animal Model.

An enlarged bone tunnel may affect the graft-bone integration and pose a problem for revision anterior cruciate ligament (ACL) surgery. The purpose of this study was to evaluate the effect of remnant preservation on tibial tunnel enlargement in ACL reconstruction with polyethylene terephthalate (PET) artificial ligament. Twenty-four skeletally mature male beagles underwent ACL reconstruction with PET artificial ligament for both knees. One knee was reconstructed with remnant preservation using sleeve technique (remnant group), while the contralateral was reconstructed without remnant preservation (control group). The animals were sacrificed at 1 day, 6 weeks, and 12 weeks after surgery for further evaluation including macroscopic observation, microcomputed tomography (micro-CT), histological assessment, and biomechanical testing. The remnant group had better synovial coverage than the control group at 6 and 12 weeks after surgery. The micro-CT analysis showed the tibial tunnel area (TTA) of the remnant group was significantly smaller and the bone volume/total volume fraction (BV/TV) value was higher than those of the control group at 6 and 12 weeks. Moreover, TTA and BV/TV at each time point were divided into three groups according to the different grade of synovial coverage. Significant association was observed between the synovial coverage degree and the TTA and BV/TV values. The histological assessment revealed that the interface width between the graft and host bone in the remnant group was smaller than that in the control group in the tibial tunnels at 6 and 12 weeks. Moreover, the remnant group had better failure load and stiffness than the control group at 12 weeks. The remnant preservation using sleeve technique could effectively promote the synovial coverage of the graft, decrease the risk of tibial tunnel enlargement by sealing the bone tunnel entrance, and enhance the biological environment for graft-bone healing after ACL reconstruction using PET artificial ligament. This technique provides a potential solution for bone tunnel enlargement following artificial ligament surgery for the acute ACL rupture in the clinical practice.

Silk enhances the ligamentization of the polyethylene terephthalate artificial ligament in a canine anterior cruciate ligament reconstruction model.

Anterior cruciate ligament (ACL) reconstruction is the leading treatment for ACL rupture. Ligament Advanced Reinforcement System (LARS), which is made of polyethylene terephthalate (PET), is the most frequently used artificial ligament for ACL reconstruction. However, PET is hydrophobic, so it is difficult to induce the ingrowth of the autologous tissue. The aim of this study is to explore the effects of silk hybrid on the ligamentization of the PET artificial ligament in a canine ACL reconstruction model. Silk/PET hybrid suspensory ligament was fabricated with silk in the weft yarn and PET in the warp yarn, while PET suspensory ligament was fabricated with PET in both the weft and warp yarns. After fabrication, the micromorphology of the ligaments was observed and mechanical testing was performed. Though the failure loads of the degummed silk/PET hybrid suspensory ligaments were significantly lower than those of the PET suspensory ligaments (P < 0.001), both of them were enough for ACL reconstructions of beagle dogs. In the animal study, 14 beagle dogs were divided into PET suspensory ligament group and silk/PET hybrid suspensory ligament group randomly, with 7 dogs in each. The dogs underwent ACL reconstructions in their right knees. At postoperative 6 months, the dogs were sacrificed, and the specimens were evaluated with gross observation, histology, immunohistochemistry, and mechanical testing. The histological and immunohistochemical results showed that the native ACL of the beagle dog held abundant fibroblasts and collagen. The PET-regenerated ligament was loose, and there was a small amount of autologous tissue and collagen. Compared to the PET-regenerated ligament, the silk/PET hybrid-regenerated ligament had a compact structure, and there was more regenerated autologous tissue and collagen. In conclusion, compared to the PET ligament, the silk/PET hybrid ligament kept greater ability to induce the ingrowth of the autologous tissue, indicating that the silk hybrid had enhanced the ligamentization of the PET artificial ligament.

Dual-layer aligned-random nanofibrous scaffolds for improving gradient microstructure of tendon-to-bone healing in a rabbit extra-articular model.

BACKGROUND: Tendon/ligament injuries are common sports injuries. Clinically, the repair of a ruptured tendon or ligament to its bony insertion is needed, but the enthesis structure is not well reestablished following surgical repair. Herein, we fabricated dual-layer aligned-random scaffold (ARS) by electrospinning and aimed to investigate the effect of the scaffold on tendon-to-bone healing in vivo. MATERIALS AND METHODS: The random and dual-layer aligned-random silk fbroin poly(L-lactic acid-co-e-caprolactone) (P(LLA-CL)) nanofibrous scaffolds were successfully fabricated by electrospinning methods. Ninety New Zealand white rabbits were randomly divided into three groups (random scaffold [RS], ARS, and control groups), and they were subjected to surgery to establish an extra-articular tendon-to-bone healing model with autologous Achilles tendon. RESULTS: Histological assessment showed that the ARS significantly increased the area of metachromasia, decreased the interface width, and improved collagen maturation and organization at the tendon-bone interface compared with the RS and control groups. Microcomputed tomography analysis showed that the bone tunnel area of RS and ARS groups was significantly smaller than those of the control group. Real-time polymerase chain reaction showed that BMP-2 and osteopontin expression levels of the tissue at the interface between the bone and graft in the RS and ARS groups were higher than those of the control group at 6 weeks. Collagen I expression level of the ARS group was significantly higher than those of the RS and control groups at 6 and 12 weeks. Moreover, the ARS groups had a better ultimate load-to-failure and stiffness than the RS and control groups. CONCLUSION: ARS could effectively augment the tendon-to-bone integration and improve gradient microstructure in a rabbit extra-articular model by inducing the new bone formation, increasing the area of fibrocartilage, and improving collagen organization and maturation. The dual-layer aligned-random silk fibroin/P(LLA-CL) nanofibrous scaffold is proved to be a promising biomaterial for tendon-to-bone healing.

Silk fibroin and hydroxyapatite segmented coating enhances graft ligamentization and osseointegration processes of the polyethylene terephthalate artificial ligament in vitro and in vivo.

The inferior biocompatibility of the polyethylene terephthalate (PET) artificial ligament may lead to poor healing in both the intra-articular part (IAP) and the intraosseous part (IOP) after anterior cruciate ligament (ACL) reconstruction. This study aimed to systematically investigate the effect of silk fibroin (SF) and hydroxyapatite (HA) segmented coating on graft ligamentization and osseointegration processes of the PET ligament. Several techniques including scanning electron microscopy (SEM) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray diffraction (XRD) and water contact angle (WCA) measurements were carried out to validate the introduction of SF and HA. The segmented coating ligament was assessed both in vitro and in vivo. The results of SEM and cell counting kit-8 (CCK-8) assay revealed that the L929 fibroblasts and MC3T3-E1 osteoblasts exhibited better adhesion and proliferation performance on the PET-SF and PET-HA fibers, respectively, compared to those on the uncoated PET fibers. HA promoted osteogenic differentiation of MC3T3-E1 in terms of the levels of alkaline phosphatase (ALP) activity and calcium deposition. Furthermore, the in vivo study in a beagle ACL reconstruction model demonstrated that the segmented coating could enhance the graft ligamentization and osseointegration processes as indicated by the better tissue infiltration in the IAP and more bone ingrowth in the IOP of the ligament than the control group according to the results of micro-computed tomography (micro-CT), histology, real-time polymerase chain reactions (RT-PCRs) and biomechanical tests. Therefore, the SF and HA segmented coating ligaments may display a great potential application for the clinical augmentation of graft healing in ACL reconstruction surgery.

Effects of polyvinylpyrrolidone-iodine on tendon-bone healing in a rabbit extra-articular model.

Polyvinylpyrrolidone-iodine (PVP-I) is a broad-spectrum antimicrobial agent, but its effects on tendon-bone healing are unclear. The purpose of this study was to investigate the effects of PVP-I on bone marrow mesenchymal stem cells (BMSCs) in vitro and on tendon-bone healing in vivo. In this study, following investigation of the concentration-dependent effects of PVP-I on the viability and osteogenic differentiation of BMSCs, the appropriate concentration of PVP-I was selected for animal experiments. New Zealand white rabbits received autologous tendon transplantation with and without PVP-I treatment of the graft tendon. Subsequently, histological examination, biomechanical testing and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analyses were conducted. At 6 weeks post-surgery, connective tissue and osteogenesis was observed at the tendon-bone interface in the PVP-I group. At 12 weeks post-surgery, the interface width in the PVP-I group was much narrower compared with that of the control group. Furthermore, the biomechanical properties of the PVP-I group were significantly stronger than those in the control group (P<0.05). RT-qPCR examination revealed that the mRNA levels of bone morphogenetic protein-2 and osteopontin in the PVP-I group were higher than those in the control group at 6 weeks (P<0.05). In conclusion, these results indicated that PVP-I promoted tendon-bone healing via osteogenesis.

Electrospun silk fibroin mat enhances tendon-bone healing in a rabbit extra-articular model.

OBJECTIVE: To investigate whether electrospun silk fibroin (SF) mat wrapping could enhance tendon-bone healing of soft tissue graft. RESULTS: Rabbit bone marrow-derived mesenchymal stem cells proliferated well on electrospun SF mat. The autologous Achilles tendon wrapped with electrospun SF mat was transplanted into the bone tunnel (experimental group) in a rabbit extra-articular model, while the unwrapped tendon was transplanted as control group. The electrospun SF mat wrapping could enhance tendon-bone healing of autologous tendon evaluated by micro-computed tomography scanning, histological examination and mechanical testing. At 6 and 12 weeks post-operatively, the failure loads of experimental group were both significantly higher than those of control group (40.5 ± 6.3 vs. 31.8 ± 4.6 N, P = 0.039 at 6 weeks; 67.1 ± 9. vs. 52.2 ± 4.7 N, P = 0.012 at 12 weeks). CONCLUSION: The electrospun SF mat wrapping could enhance tendon-bone healing of soft tissue graft.

Local delivery of controlled-release simvastatin to improve the biocompatibility of polyethylene terephthalate artificial ligaments for reconstruction of the anterior cruciate ligament.

The Ligament Advanced Reinforcement System has recently been widely used as the primary graft of choice in anterior cruciate ligament (ACL) reconstruction. But the biological graft-bone healing still remains a problem. Previous studies have shown that simvastatin (SIM) stimulates bone formation. The objective of this study was to investigate whether surface coating with collagen containing low-dose SIM microsphere could enhance the surface biocompatibility of polyethylene terephthalate (PET) artificial ligaments to accelerate graft-to-bone healing. The in vitro studies demonstrated that bone marrow stromal cells on the collagen-coated PET scaffolds (COL/PET) and simvastatin/collagen-coated PET scaffolds (SIM/COL/PET) proliferated vigorously. Compared with the PET group and the COL/PET group, SIM could induce bone marrow stromal cells' osteoblastic differentiation, high alkaline phosphatase activity, more mineralization deposition, and more expression of osteoblast-related genes, such as osteocalcin, runt-related transcription factor 2, bone morphogenetic protein-2, and vascular endothelial growth factor, in the SIM/COL/PET group. In vivo, rabbits received ACL reconstruction with different scaffolds. Histological analysis demonstrated that graft-bone healing was significantly greater with angiogenesis and osteogenesis in the SIM/COL/PET group than the other groups. In addition, biomechanical testing at the eighth week demonstrated a significant increase in the ultimate failure load and stiffness in the SIM/COL/PET group. The low dose of SIM-sustained release from SIM/COL/PET promoted the graft-bone healing via its effect on both angiogenesis and osteogenesis. This study suggested that collagen containing low-dose SIM microsphere coating on the surface of PET artificial ligaments could be potentially applied for ACL reconstruction.

A synthetic bridging patch of modified co-electrospun dual nano-scaffolds for massive rotator cuff tear.

Massive rotator cuff tears (MRCTs) are difficult to repair because of the retraction and poor mobility of torn tendons. In the current study, co-electrospun dual nano-scaffolds of poly(lactic-co-glycolic acid)/collagen I-polycaprolactone/nanohydroxyapatite (PLGA/Col-PCL/nHA) were fabricated and used to bridge MRCTs of infraspinatus tendons in a rabbit model. PLGA-PCL served as a control. The PLGA or the PLGA/Col sides of the dual scaffolds connected the tendon stumps. The PCL or PCL/nHA side was inserted into the bone tunnel at the insertion of the infraspinatus tendon. Fibroblasts showed higher viability and collagen secretion when seeded on a PLGA/Col scaffold compared to a PLGA scaffold. Osteoblasts seeded on a PCL/nHA scaffold grew better with higher mineralization than on a PCL scaffold. Histologically, collagen regenerated along PLGA scaffolds, but showed poor ingrowth to scaffolds compared with the PLGA/Col group. Newly formed bone was observed on the PCL scaffold, but was less than that on the PCL/nHA scaffold. At 6 weeks post repair, the regenerated tendon in both groups had similar maximum load to failure and ultimate stress but significantly lower stiffness in the PLGA-PCL group and a higher cross-sectional area in the PLGA/Col-PCL/nHA group compared with normal values. At 12 weeks, the maximum failure load, ultimate stress and cross-sectional areas of the regenerated tendon in the PLGA/Col-PCL/nHA group were significantly higher than in the PLGA-PCL and normal groups. The biomechanical properties of the PLGA-PCL group were similar to normal except for a larger cross-sectional area. Our data showed that the co-electrospun dual nano-scaffolds are promising in bridging MRCTs. Doping with Col and nHA further strengthens tissue regeneration.