Incidence of Venous Thromboembolism after Primary Total Hip Arthroplasty with Mechanical Prophylaxis in Hong Kong Chinese.

Purpose: The incidence of deep vein thrombosis (DVT) following total hip arthroplasty (THA) without chemoprophylaxis could be as high as 50% in Caucasians. However, according to several subsequent studies, the incidence of venous thromboembolic events (VTE) in Asians was much lower. The routine use of chemoprophylaxis, which could potentially cause increased bleeding, infection, and wound complications, has been questioned in low-incidence populations. The objective of this study is to determine the incidence of VTE after primary THA without chemoprophylaxis in an Asian population using a fast-track rehabilitation protocol and to verify the safety profile for use of 'mechanical prophylaxis alone' in patients with standard risk of VTE. Materials and Methods: This is a retrospective cohort study of 542 Hong Kong Chinese patients who underwent primary THA without chemoprophylaxis. All patients received intermittent pneumatic compression and graduated compression stockings as mechanical prophylaxis. Multimodal pain management was applied in order to facilitate early mobilisation. Routine duplex ultrasonography was performed between the fourth and seventh postoperative day for detection of proximal DVT. Results: All patients were Chinese (mean age, 63.0±11.9 years). Six patients developed proximal DVT (incidence rate, 1.1%). None of the patients had symptomatic or fatal pulmonary embolism. Conclusion: The incidence of VTE after primary THA without chemical prophylaxis can be low in Asian populations when following a fast-track rehabilitation protocol. Mechanical prophylaxis alone can be regarded as a reasonably safe practice in terms of a balanced benefit-to-risk ratio for Asian patients with standard risk of VTE.

Who are less likely to return to work after getting injured on duty? A 12-month epidemiological evaluation in an orthopedic and traumatology center in Hong Kong.

OBJECTIVES: Cases of injury on duty (IOD) are common in Hong Kong, but literature on this group of patients is limited. This study aims to describe local IOD cases' epidemiological characteristics and identify factors affecting return to work (RTW) outcomes. METHODS: This is a retrospective epidemiological study of IOD patients in the orthopedic and traumatology center of Yan Chai Hospital in 2016, using the hospital's electronic clinical record analysis and reporting system; 323 out of the 10 730 patients (M:F = 206:117; mean age 46.9 ± 11.3) were included. Data on demographics, the injury episode, administrative procedures, treatment and rehabilitation were collected. Outcomes were measured by "RTW" and "time to RTW from injury." RESULTS: Around 80% of patients had a successful RTW and the mean time to RTW was 10.6 ± 9.0 months. Patients who were female, divorced or widowed and living alone in a public rental flat were less likely to RTW. Psychiatric consultations (OR 13.70, P < .001), legal disputes (OR 8.20, P < .001) and more than 5 months of waiting time for physiotherapy (OR 3.89, P = .002) were the strongest among the numerous risk factors for non-RTW. An increase in one visit to the general outpatient clinic and the presence of legal disputes had lengthened the time to RTW by 4.8 days (P < .001) and 18.0 months (P < .001), respectively. CONCLUSIONS: Several demographic, psychosocial and administrative factors were negatively associated with RTW in the local population. Recommendations were made for healthcare providers and policymakers accordingly.

Tibial tray thickness does not significantly increase medial tibial bone resorption: Using tibial bone density as an objective measurement method.

BACKGROUND: Recent studies have reported the occurrence of medial tibial bone resorption following total knee replacement. One study proposed that a thick tibial tray results in stress shielding and increases the risk of bone resorption, but its findings were based on subjective radiological assessment. This study aimed to verify this hypothesis and to objectively quantify medial tibial bone density by using serial measurements with digital radiological densitometry. METHODS: This was a retrospective cohort study involving 140 patients (70 thick tray vs. 70 thin tray) with cobalt-chromium implants with at least 24 months of follow-up. Standard radiographs were reviewed to look for incidence of medial tibial bone loss. Serial measurement of medial tibial bone density was also performed using the method of digital radiological densitometry. RESULTS: There was no significant difference in the incidence of medial tibial bone loss. Both groups showed a significant drop in medial tibial bone density after operation (P < 0.01). Medial tibial bone density of the thick-tray cohort was significantly higher than the thin-tray cohort at one year (93.3 vs. 83.1 Greyscale; P = 0.04), but not at two and three years. Clinical outcomes in terms of postoperative range of motion, Knee Society score and complication rates were similar. CONCLUSIONS: Medial tibial bone resorption is a common phenomenon. Implants with thicker tibial trays suffer less than those with thinner trays at one year, but the difference is transient and does not affect clinical outcome.