Michael Tim-Yun Ong

Bio: Michael Tim-Yun Ong is an academic researcher from The Chinese University of Hong Kong. The author has contributed to research in topics: Medicine & Anterior cruciate ligament reconstruction. The author has an hindex of 4, co-authored 15 publications receiving 66 citations. Previous affiliations of Michael Tim-Yun Ong include Alice Ho Miu Ling Nethersole Hospital.

Sarcopenia: Current treatments and new regenerative therapeutic approaches

Abstract: Sarcopenia is characterized by loss of muscle and reduction in muscle strength that contributes to higher mortality rate and increased incidence of fall and hospitalization in the elderly. Mitochondria dysfunction and age-associated inflammation in muscle are two of the main attributors to sarcopenia progression. Recent clinical trials on sarcopenia therapies such as physical exercise, nutraceutical, and pharmaceutical interventions have revealed that exercise is the only effective strategy shown to alleviate sarcopenia. Unlike nutraceutical and pharmaceutical interventions that showed controversial results in sarcopenia alleviation, exercise was found to restore mitochondria homeostasis and dampen inflammatory responses via a complex exchange of myokines and osteokines signalling between muscle and bone. However, as exercise have limited benefit to immobile patients, the use of stem cells and their secretome are being suggested to be novel therapeutics that can be catered to a larger patient population owing to their mitochondria restoration effects and immune modulatory abilities. As such, we reviewed the potential pros and cons associated with various stem cell types/secretome in sarcopenia treatment and the regulatory and production barriers that need to be overcome to translate such novel therapeutic agents into bedside application. Translational potential: This review summarizes the causes underlying sarcopenia from the perspective of mitochondria dysfunction and age-associated inflammation, and the progress of clinical trials for the treatment of sarcopenia. We also propose therapeutic potential of stem cell therapy and bioactive secretome for sarcopenia.

Wrist Arthroscopy under Portal Site Local Anesthesia (PSLA) without Tourniquet.

Abstract: Wrist arthroscopy is typically performed under general or regional anesthesia with the aid of a tourniquet to maintain a bloodless field. Since the late 1970s, local anesthesia using intraarticular infiltration has been advocated for both diagnostic and therapeutic procedures in knee and ankle arthroscopy, with good results.1,2 Nevertheless, the large volume of anesthetic solution required for an effective procedure carries a potential risk.3 Rolf et al described the technique of injecting anesthetic solution into the portal sites alone and reported satisfactory results.4 We have been performing wrist arthroscopy under portal site local anesthesia (PSLA) without a tourniquet since 1998. The aim of the present study was to assess the efficacy, safety, and complications of PSLA and whether this can be recommended for routine wrist arthroscopy.

Health outcomes of sarcopenia: a systematic review and meta-analysis.

Abstract: Objective The purpose of this study was to perform a systematic review to assess the short-, middle- and long-term consequences of sarcopenia. Methods Prospective studies assessing the consequences of sarcopenia were searched across different electronic databases (MEDLINE, EMBASE, EBM Reviews, Cochrane Database of Systematic Reviews, EBM Reviews ACP Journal Club, EBM Reviews DARE and AMED). Only studies that used the definition of the European Working Group on Sarcopenia in Older People to diagnose sarcopenia were included. Study selection and data extraction were performed by two independent reviewers. For outcomes reported by three or more studies, a meta-analysis was performed. The study results are expressed as odds ratios (OR) with 95% CI. Results Of the 772 references identified through the database search, 17 were included in this systematic review. The number of participants in the included studies ranged from 99 to 6658, and the duration of follow-up varied from 3 months to 9.8 years. Eleven out of 12 studies assessed the impact of sarcopenia on mortality. The results showed a higher rate of mortality among sarcopenic subjects (pooled OR of 3.596 (95% CI 2.96–4.37)). The effect was higher in people aged 79 years or older compared with younger subjects (p = 0.02). Sarcopenia is also associated with functional decline (pooled OR of 6 studies 3.03 (95% CI 1.80–5.12)), a higher rate of falls (2/2 studies found a significant association) and a higher incidence of hospitalizations (1/1 study). The impact of sarcopenia on the incidence of fractures and the length of hospital stay was less clear (only 1/2 studies showed an association for both outcomes). Conclusion Sarcopenia is associated with several harmful outcomes, making this geriatric syndrome a real public health burden.

Platelet Rich Plasma: New Insights for Cutaneous Wound Healing Management

Abstract: The overall increase of chronic degenerative diseases associated with ageing makes wound care a tremendous socioeconomic burden. Thus, there is a growing need to develop novel wound healing therapies to improve cutaneous wound healing. The use of regenerative therapies is becoming increasingly popular due to the low-invasive procedures needed to apply them. Platelet-rich plasma (PRP) is gaining interest due to its potential to stimulate and accelerate the wound healing process. The cytokines and growth factors forming PRP play a crucial role in the healing process. This article reviews the emerging field of skin wound regenerative therapies with particular emphasis on PRP and the role of growth factors in the wound healing process.

Circulating factors associated with sarcopenia during ageing and after intensive lifestyle intervention

Abstract: BACKGROUND Ageing, chronic diseases, prolonged inactivity, and inadequate nutrition pose a severe threat to skeletal muscle health and function. To date, experimental evidence suggests that ageing-related subclinical inflammation could be an important causative factor in sarcopenia. Although inflammatory signalling has been implicated in the pathogenesis of experimental animal models of sarcopenia, few studies have surveyed the clinical association between circulating factors and muscle mass in patients before and after lifestyle interventions. In this study, we evaluated whether proinflammatory cytokines are associated with the onset of sarcopenia, which circulating factors are associated with the severity of sarcopenia, and how these factors change after lifestyle interventions in sarcopenic elderly persons. METHODS A total of 56 elderly subjects (age ≥ 60 years) with sarcopenia and 56 elderly non-sarcopenic subjects, who met entry criteria and had given informed consent, were selected from the Peking Union Medical College Hospital multicentre prospective longitudinal sarcopenia study for testing relevant circulating factors. Thirty-two elderly subjects from the sarcopenic cohort completed a 12 week intensive lifestyle intervention programme with whey supplements (30 g/day) and a personalized resistance training regimen. The levels of proinflammatory cytokines and metabolic hormones, pre-intensive and post-intensive lifestyle interventions, were measured. RESULTS The sarcopenic group was significantly older (72.05 ± 6.54 years; P 11.15 pg/mL) and TWEAK (>1276.48 pg/mL) were associated with a 7.6-fold and 14.3-fold increased risk of sarcopenia, respectively. After adjustment for confounding variables, high levels of TWEAK were still associated with a 13.4-fold increased risk of sarcopenia. Intensive lifestyle interventions led to significant improvements in sarcopenic patients' muscle mass and serum profiles of TWEAK, TNF-α, IL-18, insulin, and adiponectin (all P < 0.05). CONCLUSIONS High levels of the inflammatory cytokines TWEAK and TNF-α are associated with an increased risk of sarcopenia, while the metabolic hormones insulin growth factor 1, insulin, and adiponectin are associated with a decreased risk of sarcopenia in our Chinese patient cohort. Intensive lifestyle interventions could significantly improve muscle mass, reduce inflammation, and restore metabolic hormone levels in sarcopenic patients. This trial was registered at clinicaltrials.gov as NCT02873676.

Arthroscopic-Assisted Combined Dorsal and Volar Scapholunate Ligament Reconstruction with Tendon Graft for Chronic SL Instability

Abstract: Background Both the dorsal and the volar portion of the scapholunate interosseous ligament (SLIL) are major stabilizers of the scapholunate (SL) joint. Most reconstruction methods to restore SL stability do not address the volar constraints and frequently fail to reduce the SL gapping. Wrist arthroscopy allows a complete evaluation of the SL interval, accompanying ligament status, and associated SL advanced collapse (SLAC) wrist changes. It enables simultaneous reconstruction of the dorsal and palmar SL ligaments anatomically with the use tendon graft in a boxlike structure. Materials and Methods From October 2002 to June 2012, the treatment method was applied in 17 patients of chronic SL instability of average duration of 9.5 months (range 1.5-18 months). There were three Geissler grade 3 and 14 grade 4 instability cases. The average preoperative SL interval was 4.9 mm (range 3-9 mm). Dorsal intercalated segment instability (DISI) deformity was present in 13 patients. Six patients had stage 1 SLAC wrist change radiologically. Concomitant procedures were performed in four patients. Description of Technique With the assistance of arthroscopy and intraoperative imaging as a guide, a combined limited dorsal and volar incision exposed the dorsal and palmar SL interval without violating the wrist joint capsule. Bone tunnels of 2.4 mm were made on the proximal scaphoid and lunate. A palmaris longus tendon graft was delivered through the wrist capsule and the bone tunnels to reduce and connect the two bones in a boxlike fashion. Once the joint diastasis is reduced and any DISI malrotation corrected, the tendon graft was knotted and sutured on the dorsal surface of the SL joint extra-capsularly in a shoe-lacing manner. The scaphocapitate joint was transfixed with Kirschner wires (K-wires) to protect the reconstruction for 6-8 weeks. Results The average follow-up was 48.3 months (range 11-132 months). Thirteen returned to their preinjury job level. Eleven patients had no wrist pain, and six had some pain on either maximum exertion or at the extreme of motion. The average total pain score was 1.7/20 compared with the preoperative score of 8.3/20. The postoperative average total wrist performance score was 37.8/40, with an improvement of 35%. The average extension range improved for 13%, flexion range 16%, radial deviation 13%, and ulnar deviation 27%. Mean grip strength was 32.8 kg (120% of the preoperative status, 84% of the contralateral side). The average SL interval was 2.9 mm (range 1.6-5.5 mm). Recurrence of a DISI deformity was noted in four patients without symptoms. Ischemic change of proximal scaphoid was noted in one case without symptoms or progression. There were no major complications. All patients were satisfied with the procedure and outcome. Conclusion Our method of reconstructing both the dorsal and volar SL ligament, in a minimally invasive way, is a logical and effective technique to improve SL stability. The potential risk of ischemic necrosis of the carpal bone is minimized by preservation of the scaphoid blood supply, the small size of the bone tunnels created, and the inclusion of the capsule at the reconstruction site.

Platelet Concentrates in Musculoskeletal Medicine

Abstract: Platelet concentrates (PCs), mostly represented by platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) are autologous biological blood-derived products that may combine plasma/platelet-derived bioactive components, together with fibrin-forming protein able to create a natural three-dimensional scaffold. These types of products are safely used in clinical applications due to the autologous-derived source and the minimally invasive application procedure. In this narrative review, we focus on three main topics concerning the use of platelet concentrate for treating musculoskeletal conditions: (a) the different procedures to prepare PCs, (b) the composition of PCs that is related to the type of methodological procedure adopted and (c) the clinical application in musculoskeletal medicine, efficacy and main limits of the different studies.