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Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_9 | Pages 44 - 44
17 Apr 2023
Wang M Lu X Li G
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To evaluate the therapeutic effect of Pulsed Electromagnetic Field (PEMF) in the treatment of meniscal tears in the avascular region.

Seventy-two twelve-week-old male Sprague-Dawley rats with full-thickness longitudinal medial meniscal tears in the avascular region were divided into 3 groups: control group (Gcon), treated with classic signal PEMF (Gclassic), and high slew rate signal PEMF(GHSR). The HSR signal has the same pulse and burst frequencies as the classic signal, but with a higher slew rate. Macroscopic observation and histological analysis of the meniscus and articular cartilage were performed to evaluate the meniscal healing and progressions of osteoarthritis. The synovium was harvested for histological and immunofluorescent analysis to assess the intra-articular inflammation. The meniscal healing, articular cartilage degeneration, and synovitis were quantitatively evaluated according to their respective scoring system.

Dramatic degenerative changes of the meniscus and articular cartilage were noticed during gross observation and histological evaluation in the control group at 8 weeks. However, the menisci in the two treatment groups were restored to normal morphology with a smooth surface and shiny white color. Particularly, the HSR signal remarkably enhanced the fibrochondrogenesis and accelerated the remodeling process of the regenerated tissue. The meniscal healing scores of PEMF treatment groups were significantly higher than those in the control group at 8 weeks. Specifically, the HSR signal showed a significantly higher meniscal repair score than the classic signal at week 8 (P < .01). The degeneration score (Gcon versus Gclassic: P < .0001; Gcon versus GHSR: P < .0001) and synovitis score (Gcon versus Gclassic: P < .0001; Gcon versus GHSR: P = .0002) of the control groups were significantly higher than those in the two treatment groups.

PEMF promoted the healing of meniscal tears in the avascular region and restored the injured meniscus to its structural integrity in a rat model. Compared to the classic signal, the HSR signal showed the increased capability to promote fibrocartilaginous tissue formation and modulate the inflammatory environment and therefore protected the knee joint from post-traumatic osteoarthritis development.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_7 | Pages 76 - 76
4 Apr 2023
LU X BAI S LIN Y YAN L LI L WANG M JIANG Z WANG H YANG B YANG Z WANG Y FENG L JIANG X PONOMAREV E LEE W LIN S KO H LI G
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Based on Ilizarov's law of tension-stress principle, distraction histogenesis technique has been widely applied in orthopaedic surgery for decades. Derived from this technique, cranial bone transport technique was mainly used for treating cranial deformities and calvarial defects. Recent studies reported that there are dense short vascular connections between skull marrow and meninges for immune cells trafficking, highlighting complex and tight association between skull and brain. Alzheimer's disease (AD) is a progressive neurodegenerative disease and the most common cause of dementia without effective therapy. Meningeal lymphatics have been recognized as an important mediator in neurological diseases. The augmentation of meningeal lymphatic drainage might be a promising therapeutic target for AD. Our proof-of-concept study has indicated that cranial bone transport can promote ischemic stroke recovery via modulating meningeal lymphatic drainage function, providing a rationale for treating AD using cranial bone maneuver (CBM). This study aims to investigate the effects of CBM on AD and to further explore the potential mechanisms.

Transgenic 5xFAD mice model was used in this study. After osteotomy, a bone flap was used to perform CBM without damaging the dura. Open filed test, novel object recognition test and Barn's maze test were used to evaluate neurological functions of 5xFAD mice after CBM treatment. Congo red and immunofluorescence staining were used to evaluate amyloid depositions and Aβ plaques in different brain regions. Lymphangiogenesis and the level of VEGF-C were examined after CBM treatment. OVA-A647 was intra-cisterna-magna injected to evaluate meningeal lymphatic drainage function after CBM treatment.

CBM significantly improved memory functions and reduced amyloid depositions and Aβ plaques in the hippocampus of 5xFAD mice. A significant increase of meningeal lymphatic vessels in superior sagittal sinus and transverse sinus, and the upregulation of VEGF-C in meninges were observed in 5xFAD mice treated with CBM. Moreover, CBM remarkably enhanced meningeal lymphatic drainage function in 5xFAD mice (n=5-16 mice/group for all studies).

CBM may promote meningeal lymphangiogenesis and lymphatic drainage function through VEGF-C-VEGFR3 pathway, and further reduce amyloid depositions and Aβ plaques and alleviate memory deficits in AD.


Bone & Joint Research
Vol. 11, Issue 12 | Pages 862 - 872
1 Dec 2022
Wang M Tan G Jiang H Liu A Wu R Li J Sun Z Lv Z Sun W Shi D

Aims

Osteoarthritis (OA) is a common degenerative joint disease worldwide, which is characterized by articular cartilage lesions. With more understanding of the disease, OA is considered to be a disorder of the whole joint. However, molecular communication within and between tissues during the disease process is still unclear. In this study, we used transcriptome data to reveal crosstalk between different tissues in OA.

Methods

We used four groups of transcription profiles acquired from the Gene Expression Omnibus database, including articular cartilage, meniscus, synovium, and subchondral bone, to screen differentially expressed genes during OA. Potential crosstalk between tissues was depicted by ligand-receptor pairs.


Bone & Joint Research
Vol. 10, Issue 12 | Pages 767 - 779
8 Dec 2021
Li Y Yang Y Wang M Zhang X Bai S Lu X Li Y Waldorff EI Zhang N Lee WY Li G

Aims

Distraction osteogenesis (DO) is a useful orthopaedic procedure employed to lengthen and reshape bones by stimulating bone formation through controlled slow stretching force. Despite its promising applications, difficulties are still encountered. Our previous study demonstrated that pulsed electromagnetic field (PEMF) treatment significantly enhances bone mineralization and neovascularization, suggesting its potential application. The current study compared a new, high slew rate (HSR) PEMF signal, with different treatment durations, with the standard Food and Drug Administration (FDA)-approved signal, to determine if HSR PEMF is a better alternative for bone formation augmentation.

Methods

The effects of a HSR PEMF signal with three daily treatment durations (0.5, one, and three hours/day) were investigated in an established rat DO model with comparison of an FDA-approved classic signal (three hrs/day). PEMF treatments were applied to the rats daily for 35 days, starting from the distraction phase until termination. Radiography, micro-CT (μCT), biomechanical tests, and histological examinations were employed to evaluate the quality of bone formation.


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_6 | Pages 64 - 64
1 Jul 2020
Lin K Wong F Wang M Teo KY Chuah SJ Ren X Wu Y Hassan A Lai RC Lim S Hui JHP Toh W Lee E Zhang S
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Osteochondral (OC) defects of the knee are associated with pain and significant limitation of activity. Studies have demonstrated the therapeutic efficacy of mesenchymal stem cell (MSC) therapies in treating osteochondral defects. There is increasing evidence that the efficacy of MSC therapies may be a result of the paracrine secretion, particularly exosomes. Here, we examine the effects of MSC exosomes in combination with Hyaluronic Acid (HA) as an injectable therapy on functional osteochondral regeneration in a rabbit osteochondral defect model.

Exosomes were purified from human MSC conditioned medium by size fractionation. A circular osteochondral defect of 4.5 mm diameter and 2.5 mm depth was surgically created in the trochlear grooves of 16 rabbit knees. Thereafter, eight knees received three weekly injections of 200 µg of exosomes in one ml of 3% HA, and the remaining eight knees received three weekly injections of one ml of 3% HA only. The rabbits were sacrificed at six weeks. Analyses were performed by macroscopic and histological assessments, and functional competence was analysed via Young Modulus calculation at five different points (central, superior, inferior, medial and lateral) of the repaired osteochondral defect site.

MSC exosomes displayed a modal size of 100 nm and expressed exosome markers (CD81, TSG101 and ALIX). When compared to HA alone, MSC exosomes in combination with HA showed significantly better repair histologically and biomechanically. The Young Modulus was higher in 4 out of the 5 points. In the central region, the Young Modulus of MSC exosome and HA combination therapy was significantly higher: 5.42 MPa [SD=1.19, 95% CI: 3.93–6.90] when compared to HA alone: 2.87 MPa [SD=2.10, 95% CI: 0.26–5.49], p < 0 .05. The overall mean peripheral region was also significantly higher in the MSC exosome and HA combination therapy group: 5.87 MPa [SD=1.19, 95% CI: 4.40–7.35] when compared to HA alone: 2.70 MPa [SD=1.62, 95% CI: 0.79–4.71], p < 0 .05. The inferior region showed a significantly higher Young Modulus in the combination therapy: 7.34 MPa [SD=2.14, 95% CI: 4.68–10] compared to HA alone: 2.92 MPa [SD=0.98, 95% CI: 0.21–5.63], p < 0.05. The superior region showed a significantly higher Young Modulus in the combination therapy: 7.31 MPa [SD=3.29, 95% CI: 3.22–11.39] compared to HA alone: 3.59 MPa [SD=2.55, 95% CI: 0.42–6.76], p < 0.05. The lateral region showed a significantly higher Young Modulus in the combination therapy: 8.05 MPa [SD=2.06, 95% CI: 5.49–10.61] compared to HA alone: 3.56 MPa [SD=2.01, 95% CI: 1.06–6.06], p < 0.05. The medial region showed a higher Young Modulus in the combination therapy: 6.68 MPa [SD=1.48, 95% CI: 4.85–8.51] compared to HA alone: 3.45 MPa [SD=3.01, 95% CI: −0.29–7.19], but was not statistically significant. No adverse tissue reaction was observed in all the immunocompetent animals treated with MSC exosomes.

Three weekly injections of MSC exosomes in combination with HA therapy results in a more functional osteochondral regeneration as compared to HA alone.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_6 | Pages 51 - 51
1 Apr 2018
Avadi MS Meng L Anderson J Fisher J Wang M Jin Z Qiu Y Williams S
Full Access

INTRODUCTION

Avascular necrosis (AVN) of the femoral head (FH) initiates from biological disruptions in the bone and may progress to mechanical failure of the hip. Mechanical and structural properties of AVN bone have not been widely reported, however such understanding is important when designing therapies for AVN. Brown et al.[1] assessed mechanical properties of different regions of AVN FH bone and reported 52% reduction in yield strength and 72% reduction in elastic modulus of necrotic regions when compared to non-necrotic bone. This study aimed to characterise structural and mechanical properties of FH bone with AVN and understand the relationship between lesion volume and associated mechanical properties.

METHODS

Twenty FH specimens from patients undergoing hip arthroplasty for AVN and six non-pathological cadaveric FH controls were collected. Samples were computed tomography scanned and images analysed for percentage lesion volume with respect to FH volume. Samples were further divided for structural and mechanical testing. The mechanical property group were further processed to remove 9mm cylindrical bone plugs from the load bearing and non-load-bearing regions of the FHs. FH and bone plug samples were tested in compression (1mm/min); elastic modulus and yield stress were calculated.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_28 | Pages 57 - 57
1 Aug 2013
Wang J Hu L Zhao C Su Y Wang T Wang M
Full Access

Objectives

Percutaneous iliosacral screw placement is a standard, stabilization technique for pelvic fractures. The purpose of this study was to assess the effectiveness of a novel biplanar robot navigation aiming system for percutaneous iliosacral screw placement in a human cadaver model.

Methods

A novel biplanar robot navigation aiming system was used in 16 intact human cadaveric pelvises for percutaneous iliosacral screw insertion. The number of successful screw placements and mean time for this insertion and intra-operative fluoroscopy per screw-pair were recorded respectively to evaluate the procedure. The accuracy of the aiming process was evaluated by computed tomography.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 540 - 540
1 Sep 2012
Wang M Li H Hoey K Hansen E Niedermann B Helming P Wang Y Aras E Schattiger K Bunger C
Full Access

Study design: We conducted a prospective cohort study of 448 patients with a variety of spinal metastases.

Objective

To compare the predictive value of the Tokuhashi scoring system (T12) and its revised edition (T15) for life expectancy both in the entire study group as well as in the various primary tumor subgroups.

Summary of background data

In 1990 Tokuhashi and coworkers formulated a one point-addition-type prognostic scoring system with a total sum of 12 points for preoperative prediction of life expectancy as an adjunct in selecting appropriate treatment. Because the site of the primary tumor influences ultimate survival, the scoring system was revised in 2005 to a total sum of 15 points based on the origin of the primary tumor.