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The Bone & Joint Journal
Vol. 105-B, Issue 6 | Pages 688 - 695
1 Jun 2023
Johnston GHF Mastel M Sims LA Cheng Y

Aims

The aims of this study were to identify means to quantify coronal plane displacement associated with distal radius fractures (DRFs), and to understand their relationship to radial inclination (RI).

Methods

From posteroanterior digital radiographs of healed DRFs in 398 female patients aged 70 years or older, and 32 unfractured control wrists, the relationships of RI, quantifiably, to four linear measurements made perpendicular to reference distal radial shaft (DRS) and ulnar shaft (DUS) axes were analyzed: 1) DRS to radial aspect of ulnar head (DRS-U); 2) DUS to volar-ulnar corner of distal radius (DUS-R); 3) DRS to proximal capitate (DRS-PC); and 4) DRS to DUS (interaxis distance, IAD); and, qualitatively, to the distal ulnar fracture, and its intersection with the DUS axis.


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_3 | Pages 20 - 20
1 Mar 2021
McLaren S Sauder D Sims L Khan R Cheng Y
Full Access

Outcomes following carpal tunnel release are generally favorable. Understanding factors that contribute to inferior outcomes may allow for strategies targeted at improving results in these patients. Our purpose was to determine if patients' underlying personality traits, specifically resiliency and catastrophization, impact their post-operative outcomes following carpal tunnel release.

A prospective case series was performed. Based on our power analysis, 102 patients were recruited. Patients completed written consent, the Boston Carpal Tunnel Questionnaire (BCTQ), the Pain Catastrophizing Scale (PCS) and the Brief Resiliency Scale (BRS). A single surgeon, or his resident under supervision, then performed an open carpal release under local anaesthetic. Our primary outcome measure was a repeat BCTQ at three- and six-months. Univariate and multivariate analysis was performed to assess the correlation between PCS and BRS scores and final BCTQ scores.

Forty-three and sixty-three participants completed the BCTQ at three and six months respectively. All patients showed improvement in their symptoms (p = 0.001). There was no correlation between patients PCS or BRS and the amount of improvement. There was also no correlation between PCS or BRS and the patients' raw scores at baseline or follow-up.

Patients self-assessed resiliency and degree of pain catastrophization has no correlation with the amount of improvement they have three or six months post-operatively. Most patients improved following carpal tunnel release, and patients with low resiliency and high levels of pain catastrophization should expect comparable outcomes to patients without these features.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_8 | Pages 81 - 81
1 Apr 2017
Cheng Y Wang F Su Y Ko J
Full Access

Background

MicroRNAs are non-coding small RNAs that reportedly regulate mRNA targets or protein translation of various tissues in physiological and pathological contexts. This study was undertaken to characterise the contributions of microRNA-29a (miR-29a) to the progression of estrogen deficiency-mediated excessive osteoclast resorption and bone loss.

Methods

Osteoblast-specific transgenic mice overexpressing miR-29a driven by osteocalcin promoter (C57BL/6JNarl-TgOCN-mir29a) or wild-type mice were subjected to bilateral ovariectomy. Bone mineral density, trabecular microarchitecture and osteoclast distribution was quantified by μCT and histomorphometry. Primary CD11b+CSF-1R+ preosteoclasts were isolated for detecting ex vivo osteoclast differentiation. Gene expression and transcription factor-promoter interaction were quantified by RT-PCR and chromatin immunoprecipitation.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_2 | Pages 81 - 81
1 Jan 2017
Cheng Y Samizadeh S Coathup M Blunn G
Full Access

Mesenchymal stem cells (MSCs) are believed to be immune-privileged due to lack of antigen-presenting-cell related markers, however, evidence suggests that MSCs are immunogenic and are attacked by the immune system. Our research investigates the hypothesis that there are differences between MSC clones from the same individual in terms of their morphology, proliferation, differentiation and immune profile. Our goal is to discover immune-privileged stem cells, which can act as a universal allogenic mesenchymal stem cell donor to facilitate bone ingrowth for osteosarcoma patients status post tumor excision and prosthesis implantation.

Serial dilutions of bone-marrow derived (BMMSCs) and adipose derived mesenchymal stem cells (ADMSCs) from same animal were carried out in order to isolate single-cell clones. From a single animal we obtained 3 clones from BMMSCs and 3 from ADMSCs. This procedure was repeated for another other 2 animals. The proliferation rate and cell doubling time of each clonal culture was measured. The proliferation rate of mixed clonal cultures was also measured. The tri-differentiation potential of the clonal cultures was compared and a comparison was also made with the original isolates from bone marrow and fat. The immune-privileged properties were measured by flow cytometry and immuno-staining for the major histocompatibility complex (MHC) antigens. To measure the immune response a mixed leucocyte reaction was used but where leucocytes from a different individual were mixed with the clonal MSC cells.

All isolates were able to differentiate into osteoblasts, chondrocytes and adipocytes. All clonal cultures revealed significantly different proliferation rates and doubling times when compared with each other and with mixed cultures. All clonal cultures showed different surface marker presentations, which included differences in the expression of MHC antigens. One clone isolated from ADMSCs showed lack of MHCI and MHCII. Our mixed leucocyte reaction and MHC staining showed variety of immune-modulation and this was related to the expression of the MHC antigens.

All clones tri-differentiated and therefore show a degree of ‘stemness’. MSCs are generally are believed not to express MHC II and to be immune-privileged. However, this study shows that the expression of these antigens in clones isolated from bone marrow and from fat is variable. A heterogeneous result indicates individual differences between MSCs, even from same origin. The immune response elicited by MSCs is complicated. MSCs have been shown to release interleukin 10, which could inhibit the immune response but on the other hand interferon-gamma could enhance MHCII presentation in some MSCs. Our results confirmed our hypothesis because clonal cultures isolated from different sources of MSCs in the same animal showed significant differences in proliferation rate, morphology and surface marker presentation. Mesenchymal stem cells are not immunogenic or immune-privileged. Individual differences highlighted through single-cell clonal cultures may be the key to finding a universal immune-privileged MSCs for allogeneic transplantation.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_16 | Pages 4 - 4
1 Oct 2016
Cheng Y Sorousheh S Coathup M Blunn G
Full Access

Mesenchymal stem cells (MSCs) are usually believed to be immune-privileged. However, immunogenic MSCs were also reported. We hypothesize that there are differences between MSC clones from the same individual in terms of their morphology, proliferation, differentiation and immunogenicity. Our goal is to discover immune-privileged stem cells for universal allogenic MSCs transplantation.

Serial dilutions of bone-marrow derived (BMMSCs) and adipose derived mesenchymal stem cells (ADMSCs) from same animal were carried out to isolate single-cell clones. From a single animal we obtained 3 clones from BMMSCs and 3 from ADMSCs. The proliferation rate of each clonal culture and mixed clonal culture were measured. The tri-differentiation potential of the clonal cultures was compared, as well as with the original isolates from bone marrow and fat. The immune-privileged properties were measured by flow cytometry and immuno-staining for the major histocompatibility complex (MHC) antigens. Mixed leucocyte reaction (MLR) were also performed to investigate immunogenicity.

Tri-differentiation was confirmed in all isolates. All clonal cultures revealed significant different morphology and proliferation rates, compared with each other and mixed cultures. All clonal cultures showed different surface markers, inclusive of MHC antigens. One clone from ADMSCs showed lack of MHC antigens. Our MLR and MHC staining disclosed variety of immune properties.

All clones tri-differentiated which indicated a degree of ‘stemness’. MSCs are generally believed not to express MHC II, resulting in immune-privileged. Our results confirmed our hypothesis because clonal cultures isolated from different origins of same animal show differences in morphology, proliferation rate, and surface marker presentation. Individual immune differences highlighted through single-cell clonal cultures may be crucial to find universal immune-privileged MSCs as universal allogeneic donor.


The Journal of Bone & Joint Surgery British Volume
Vol. 85-B, Issue 5 | Pages 679 - 682
1 Jul 2003
Cheng Y Chien C Chen C

Free radicals, such as reactive oxygen species (ROS) which are released abruptly after deflation of an ischaemic tourniquet, cause reperfusion injuries. Ischaemic precondition (IPC), however, can reduce the injury. In clinical practice, the sequential application and release of tourniquets is often used in bilateral total knee replacement (TKR) to obtain a clearer operative field, but the effects on the production of free radicals and lipid peroxidation have not been studied.

In this study, we have observed the production of free radicals and the subsequent lipid peroxidation in bilateral TKR with sequential application of a tourniquet to examine the effect of IPC. Patients undergoing elective TKR under intrathecal anaesthesia were studied. Blood samples were obtained after spinal anaesthesia, one minute before and five and 20 minutes after release of each tourniquet. We used the lucigenin chemiluminescence analysis and the phosphatidylcholine hydroperoxide (PCOOH) assay to measure the production of ROS and lipid peroxidation.

Our results showed that production of ROS significantly increased at five and 20 minutes after release of the first tourniquet and at five minutes after release of the second tourniquet, but returned to normal at 20 minutes after the second reperfusion. The peak production of ROS was at 20 minutes after the first reperfusion; lipid peroxidation did not change significantly.

We conclude that in spite of significant production of ROS after the release of tourniquet, the IPC phenomenon occurs during bilateral TKR with sequential application of a tourniquet.