Robotic arm-assisted unicondylar knee arthroplasty resulted in superior radiological accuracy: a propensity score-matched analysis.

INTRODUCTION: Unicompartmental knee arthroplasty (UKA) is an effective surgical treatment for medial compartment arthritis of the knee, yet surgical outcomes are directly related to surgical execution. Robotic arm-assisted surgery aims to address these difficulties by allowing for detailed preoperative planning, real-time intraoperative assessment and haptic-controlled bone removal. This study aimed to compare the clinical and radiological outcomes between conventional manual mobile bearing and robot arm-assisted fixed bearing medial UKA in our local population. MATERIALS AND METHODS: This is a retrospective case-control study of 148 UKAs performed at an academic institution with a minimum of 1-year follow-up. 74 robotic arm-assisted UKAs were matched to 74 conventional UKAs via propensity score matching. Radiological outcomes included postoperative mechanical axis and individual component alignment. Clinical parameters included a range of motion, Knee Society knee score and functional assessment taken before, 6 and 12 months after the operation. RESULTS: Robot arm-assisted UKA produced a more neutral component coronal alignment in both femoral component (robotic -0.2 ± 2.8, manual 2.6 ± 2.3; P = 0.043) and tibial component (robotic -0.3 ± 4.0, manual 1.7 ± 5.3; P < 0.001). While the postoperative mechanical axis was comparable, robot arm-assisted UKA demonstrated a smaller posterior tibial slope (robotic 5.7 ± 2.7, manual 8.2 ± 3.3; P = 0.02). Clinical outcomes did not show any statistically significant differences. CONCLUSION: Compared with conventional UKA, robotic arm-assisted UKA demonstrated improved component alignment and comparable clinical outcomes. Improved radiological accuracy with robotic-arm assistance demonstrated promising early results.

The association between tibial torsion, knee flexion excursion and foot progression during gait in people with knee osteoarthritis: a cross-sectional study.

BACKGROUND: Lower limb malalignment is associated with gait kinematics, but there is limited information on the relationship between gait kinematics and tibial torsion in individuals with knee osteoarthritis (OA). This study aimed to investigate possible associations between tibial torsion and early stance kinematics during gait in people with mild and moderate medial knee OA. METHODS: Forty-seven participants (age: 62.1 ± 6.0 years; female/male: 37/10) diagnosed with medial knee OA were recruited from a regional hospital. Thirty of them had mild and seventeen had moderate knee OA. Lower limb alignment including tibial torsion and valgus/varus alignment were assessed by an EOS biplaner X-ray system with participants in weight-bearing position. Lower limb kinematics during gait was captured using the Vicon motion analysis system. The associations were estimated by partial Pearson correlation coefficient test. RESULTS: Our results indicated that external tibial torsion was related to early stance knee flexion excursion in participants with moderate knee OA (r = -0.58, p = 0.048), but not in participants with mild knee OA (r = 0.34, p = 0.102). External tibial torsion was associated with external foot progression angle (r = 0.48, p = 0.001), and knee varus/valgus alignment was associated with knee flexion excursion (r = -0.39, p = 0.010) in all participants. CONCLUSIONS: Both horizontal and frontal lower limb alignments were associated with knee flexion excursion at early stance of gait cycle in participants with medial knee OA. The distal rotational profile of lower limb would likely affect knee motion in sagittal plane. It implies that people with moderate knee OA could possibly benefit from correction of rotational alignment of lower limb.

Pain, balance, and mobility in people 1 year after total knee arthroplasty: a non-randomized cross-sectional pilot study contrasting posterior-stabilized and medial-pivot designs.

BACKGROUND: Total knee arthroplasty (TKA) is a common treatment for severe knee osteoarthritis. Medial-pivot TKA systems (MP-TKA) are theoretically better than posterior-stabilized TKA systems (PS-TKA) in improving static and dynamic balance of patients although it is difficult to objectively quantify these balance parameters in a clinical setting. Therefore, this pilot study aimed to evaluate the feasibility of using wearable devices in a clinical setting to examine whether people with MP-TKA have better postoperative outcomes than PS-TKA, and their balance control is more akin to age-matched asymptomatic controls. METHODS: The current cross-sectional pilot study recruited 57 participants with 2 different prosthesis designs (20 PS-TKA, 18 MP-TKA) and 19 asymptomatic controls. At 1-year post-TKA, pain, knee stiffness, and physical function were assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Static balance, mobility, and gait stability of the participants were evaluated based on data collected from wearable motion sensors during the near tandem stance, timed-up-and-go, and 6-min walk tests. RESULTS: Compared to asymptomatic controls, both TKA groups reported significantly more pain and stiffness and demonstrated reduced functional mobility, increased stride-time-variability, and impaired balance. After Bonferroni adjustment, no significant differences in pain, balance, and mobility performance were observed between PS-TKA and MP-TKA participants 1 year after surgery. However, there was a trend for increased anteroposterior sway of the lumbar and head regions in the MP-TKA participants when undertaking the near tandem stance test. The wearable motion sensors were easy to use without any adverse effects. CONCLUSIONS: It is feasible to use wearable motion sensors in a clinical setting to compare balance and mobility performance of patients with different TKA prothesis designs. Since this was a pilot study and no definite conclusions could be drawn, future clinical trials should determine the impacts of different TKA prosthesis designs on post-operative outcomes over a longer follow-up period.

Adipokine Signaling Pathways in Osteoarthritis.

Osteoarthritis (OA) is a debilitating joint disease that affects millions of individuals. The pathogenesis of OA has not been fully elucidated. Obesity is a well-recognized risk factor for OA. Multiple studies have demonstrated adipokines play a key role in obesity-induced OA. Increasing evidence show that various adipokines may significantly affect the development or clinical course of OA by regulating the pro/anti-inflammatory and anabolic/catabolic balance, matrix remodeling, chondrocyte apoptosis and autophagy, and subchondral bone sclerosis. Several signaling pathways are involved but still have not been systematically investigated. In this article, we review the cellular and molecular mechanisms of adipokines in OA, and highlight the possible signaling pathways. The review suggested adipokines play important roles in obesity-induced OA, and exert downstream function via the activation of various signaling pathways. In addition, some pharmaceuticals targeting these pathways have been applied into ongoing clinical trials and showed encouraging results. However, these signaling pathways are complex and converge into a common network with each other. In the future work, more research is warranted to further investigate how this network works. Moreover, more high quality randomised controlled trials are needed in order to investigate the therapeutic effects of pharmaceuticals against these pathways for the treatment of OA. This review may help researchers to better understand the pathogenesis of OA, so as to provide new insight for future clinical practices and translational research.

Artificial intelligence in diagnosis of knee osteoarthritis and prediction of arthroplasty outcomes: a review.

BACKGROUND: Artificial intelligence is an emerging technology with rapid growth and increasing applications in orthopaedics. This study aimed to summarize the existing evidence and recent developments of artificial intelligence in diagnosing knee osteoarthritis and predicting outcomes of total knee arthroplasty. METHODS: PubMed and EMBASE databases were searched for articles published in peer-reviewed journals between January 1, 2010 and May 31, 2021. The terms included: 'artificial intelligence', 'machine learning', 'knee', 'osteoarthritis', and 'arthroplasty'. We selected studies focusing on the use of AI in diagnosis of knee osteoarthritis, prediction of the need for total knee arthroplasty, and prediction of outcomes of total knee arthroplasty. Non-English language articles and articles with no English translation were excluded. A reviewer screened the articles for the relevance to the research questions and strength of evidence. RESULTS: Machine learning models demonstrated promising results for automatic grading of knee radiographs and predicting the need for total knee arthroplasty. The artificial intelligence algorithms could predict postoperative outcomes regarding patient-reported outcome measures, patient satisfaction and short-term complications. Important weaknesses of current artificial intelligence algorithms included the lack of external validation, the limitations of inherent biases in clinical data, the requirement of large datasets in training, and significant research gaps in the literature. CONCLUSIONS: Artificial intelligence offers a promising solution to improve detection and management of knee osteoarthritis. Further research to overcome the weaknesses of machine learning models may enhance reliability and allow for future use in routine healthcare settings.

A Randomized Controlled Study on the Use of Tourniquet in Primary Total Knee Arthroplasty.

BACKGROUND: The use and the optimal timing of tourniquet during primary total knee arthroplasty (TKA) is controversial. Most previous studies failed to show clinically significant differences in different strategies. The aim of this study was to determine how three strategies of tourniquet application affect the outcome in TKA patients. METHODS: This was a prospective randomized controlled study. Patients who undergo TKA were randomized into one of the three groups (1:1:1 ratio): tourniquet inflated from skin incision to cement hardening, tourniquet from cement application to hardening, and tourniquet from skin incision to skin closure. The perioperative blood loss, limb swelling, and complications were recorded. The level of hemoglobin, hematocrit, C-reactive protein (CRP), interleukin (IL)-6, creatine kinase (CK), and lactate dehydrogenase (LDH) were determined. Patients' thigh and TKA wound pain, Knee Society knee score (KSKS) and Knee Society functional assessment (KSFA) scores, and rehabilitation parameters were evaluated. RESULTS: A total of 90 patients were enrolled. The baseline characteristics were comparable. We only found significant difference in the intraoperative blood loss (skin to cement: 58.7 ± 36.1 mL, cement-only: 147.8 ± 107.9 mL, skin to skin: 16.3 ± 13.1 mL, p < 0.0001). There were no statistical differences in postoperative drainage, thigh/knee circumference, change of hemoglobin/hematocrit, CRP, IL-6, CK, and LDH on day 1 to day 4 after surgery. The thigh/TKA wound Visual Analogue Scale scores, KSKS score, KSFA score, and rehabilitation parameters were not significantly different at up to 6-month follow-up. No thromboembolic events were noted. CONCLUSION: Our results revealed that there was no best tourniquet strategy in TKA. Different tourniquet methods can be utilized based on surgeon preference without affecting outcomes.

Effect of Steroid in Local Infiltration Analgesia in One-Stage Bilateral Total Knee Arthroplasty: A Paired-Randomized Controlled Study.

Although local infiltration analgesia (LIA) is effective in relieving pain after total knee arthroplasty (TKA), its effect is short lasting and the optimal combination of drugs is unknown. Steroids being a potent and long-acting anti-inflammatory drug might extend LIA's effect. This study aims to evaluate the role of steroids in LIA. This is a paired-randomized controlled study involving one-stage bilateral TKA patients. LIA containing ropivacaine, ketorolac, and adrenaline with or without triamcinolone was given. One knee was randomized to receive LIA with steroids, while the other received LIA without steroids. The primary outcome was knee pain in terms of the visual analog scale (VAS). Secondary outcomes were rehabilitation progress, functional scores, and complications. Outcomes were compared between the knees of the same patient and documented up to 1 year. A total of 45 patients (90 TKAs) were included. LIA with steroid knees showed lower VAS score at rest and during activity from postoperation day 1 to 5 and at 6 weeks (p < 0.05). Passive and active range of movement was also greater in LIA with steroid group from day 1 to 7 and day 2 to 5, respectively (p < 0.05). Steroid-treated knees also achieved active straight leg raise earlier (1.2 vs. 2.0 days, p < 0.05). No differences in Knee Society Score and complication rates between both groups. Steroids in LIA offer additional and extended benefit in pain control and rehabilitation after TKA, while no adverse effects were found up to 1-year follow-up.

Psychometric Properties of Brief-Balance Evaluation Systems Test Among Multiple Populations: A Systematic Review and Meta-analysis.

OBJECTIVE: To synthesize evidence regarding the psychometric properties of the Brief-Balance Evaluation Systems Test (BESTest) in assessing postural controls across various populations. DATA SOURCES: Articles were searched in 9 databases from inception to March 2020. STUDY SELECTION: Two reviewers independently screened titles, abstracts, and full-text articles to include studies that reported at least 1 psychometric property of the Brief-BESTest. There were no language restrictions. DATA EXTRACTION: The 2 independent reviewers extracted data (including psychometric properties of Brief-BESTest) from the included studies. The methodological quality of the included studies was appraised by the Consensus-based Standards for the Selection of Health Status Measurement Instruments checklist, and the quality of statistical outcomes was assessed by the Terwee et al method. A best-evidence synthesis for each measurement property of the Brief-BESTest in each population was conducted. DATA SYNTHESIS: Twenty-four studies encompassing 13 populations were included. There was moderate to strong positive evidence to support the internal consistency (Cronbach α>0.82), criterion validity (ρ≥0.73, r≥0.71), and construct validity (ρ≥0.66, r≥0.50, area under curve>0.72) of the Brief-BESTest in different populations. Moderate to strong positive evidence supported the responsiveness of the Brief-BESTest in detecting changes in postural controls of patients 4 weeks after total knee arthroplasty or patients with subacute stroke after 4-week rehabilitation. However, there was strong negative evidence for the structural validity of this scale in patients with various neurologic conditions. The evidence for the reliability of individual items and measurement errors remains unknown. CONCLUSIONS: The Brief-BESTest is a valid (criterion- and construct-related) tool to assess postural control in multiple populations. However, further studies on the reliability of individual items and minimal clinically important difference of the Brief-BESTest are warranted before recommending it as an alternative to the BESTest and Mini-BESTest in clinical research/practice.

Exploring the relationship between pain intensity and knee moments in participants with medial knee osteoarthritis: a cross-sectional study.

BACKGROUND: High biomechanical loading is believed to be a risk factor to pain in people with knee osteoarthritis (OA), but controversial findings have been reported on the relationship between external knee adduction moment (KAM) and pain. A more comprehensive analysis considering other factor such as external knee flexion moment (KFM) could help better reveal this relationship. This study explored the relationship between external knee adduction moment and pain intensity in participants with knee osteoarthritis (OA) using an integrated path analysis model. METHODS: This was a cross-sectional study based on laboratory setting. Forty-seven participants with clinical and radiographic medial knee OA were analyzed for their external knee adduction moment (KAM) and knee flexion moment (KFM) during walking using a motion analysis system. Pain intensity was measured by visual analogue scale (VAS) and the pain subscale of the Knee Injury and Osteoarthritis Outcome Score. Varus/valgus alignment was captured and quantified using a bi-planar X-ray system. Using a path analysis model, the relationships between pain intensity, KAM, KFM, OA radiographic severity, knee varus angle and walking speed were examined. RESULTS: The proposed path model met the goodness-of-fit criteria. Based on this model, KAM had a negative effect on VAS pain indirectly through the mediation of KFM. The model indicated KAM and KFM were negatively related to one another; and KFM was positively related to VAS. The KAM index, defined as (KAM/ (KAM + KFM)), was negatively related to VAS. CONCLUSIONS: Path analysis enabled the construction of a more integrated pathokinematic framework for people with knee OA. The KAM index which reflected the load sharing on the frontal and sagittal planes also revealed its relationship with pain. Re-distribution of mechanical loading from frontal to sagittal plane might be a strategy for pain avoidance associated with mechanical irritation.

Knee joint loadings are related to tibial torsional alignments in people with radiographic medial knee osteoarthritis.

Torsional malalignment was detected in subjects with medial knee osteoarthritis (KOA) but few studies have reported the effect of torsional deformity on knee joint loads during walking. Therefore, this study examined the relationships between lower limb torsional alignments and knee joint loads during gait in people with symptomatic medial KOA using cross-sectional study design. Lower limb alignments including tibial torsion, tibiofemoral rotation and varus/valgus alignments in standing were measured by EOS low-dose bi-planar x-ray system in 47 subjects with mild or moderate KOA. The external knee adduction moment (KAM), flexion moment (KFM) and the KAM index which was defined as (KAM/ (KAM+KFM)*100) during walking were analyzed using a motion analysis system so as to estimate the knee loads. Results revealed externaltibial torsion was positively associated with KAM in subjects with moderate KOA (r = 0.59, p = 0.02) but not in subjects with mild KOA. On the contrary, significant association was found between knee varus/valgus alignment and KAM in the mild KOA group (r = 0.58, p<0.001) and a sign of association in the moderate KOA group (r = 0.47, p = 0.08). We concluded tibial torsion and knee varus/valgus mal-alignments would be associated with joint loading in subjects with moderate medial KOA during walking. Radiographic severity might need to be considered when using gait modification as a rehabilitation strategy for this condition.

Three-Dimensional Printing and Computer Navigation for Correction of Multiple Deformities in Osteogenesis Imperfecta: A Case Report.

CASE: A 44-year-old man with osteogenesis imperfecta presented with multiple debilitating musculoskeletal deformities. Bi-level osteotomies, assisted by 3-dimensional (3D)-printed patient-specific cutting guides, were performed to correct extraarticular valgus and procurvatum tibial deformities. Concomitant computer-navigated total knee arthroplasty was performed to restore neutral mechanical alignment. Postoperative x-ray showed good correction of deformities, and 1 year postoperatively, the patient is able to walk unaided with significant resolution of knee pain. CONCLUSION: 3D-printed osteotomy guides and computer navigation can be instrumental in procedures requiring a high degree of precision. With sufficient training, modern orthopaedic technologies can be implemented by surgeons themselves and combined to facilitate precise and personalized management of challenging conditions.

Acceptability and feasibility of a community-based strength, balance, and Tai Chi rehabilitation program in improving physical function and balance of patients after total knee arthroplasty: study protocol for a pilot randomized controlled trial.

BACKGROUND: The rate of falls in patients after total knee arthroplasty (TKA) is high and related to lower limb muscle weakness and poor balance control. However, since routine post-TKA rehabilitation is uncommon, it is paramount to explore alternative strategies to enhance balance and physical functioning in post-TKA patients. As Tai Chi is a proven strategy for improving balance in older people, the proposed study aims to determine the feasibility and acceptability of a 12-week community-based post-TKA multimodal Tai Chi program and to collect preliminary data with respect to the efficacy of such a program in improving balance and physical functioning in post-TKA patients as compared to usual postoperative care. METHODS: A single-blinded 2-arm pilot randomized controlled trial will recruit 52 community-dwelling post-TKA patients (aged > 60 years) in Hong Kong. In addition, 26 untreated asymptomatic controls will be recruited for comparison purposes. The TKA patients will be randomized into either a 12-week multimodal Tai Chi rehabilitation group or a postoperative usual care group (26 each). Participants will perform the outcome assessments at baseline, 6, 12, 24, and 52 weeks after TKA, while asymptomatic controls will have the same assessments at baseline, 12, and 52 weeks after baseline. The rate of recruitment, retention, and attrition, as well as adherence to the intervention, will be measured and used to determine the feasibility of the study and whether a full-scale effectiveness trial is warranted. Further, qualitative interviews will be conducted to explore the acceptability and possible barriers to the implementation of the intervention. Primary and secondary outcomes including both patient-reported surveys and performance-based tests will be compared within and between groups. DISCUSSION: The study will determine the feasibility and acceptability/potential efficacy of community-based rehabilitation for post-TKA patients and assess whether the intervention has the potential to be assessed in a future fully powered effectiveness trial. The findings will also be used to refine the study design and guide the conduction of a future definitive randomized controlled trial. TRIAL REGISTRATION: ClinicalTrials.gov NCT03615638. Registered on 30 May 2018. https://clinicaltrials.gov/ct2/show/NCT03565380.

Imaging of knee osteoarthritis: A review of current evidence and clinical guidelines.

BACKGROUND: Knee osteoarthritis (OA) is one of the most common and debilitating degenerative joint diseases worldwide. While radiography is the most commonly used imaging modality, it is associated with drawbacks which newer modalities such as magnetic resonance imaging (MRI) and ultrasound could overcome. Nevertheless, the role of imaging in clinical practice and research in knee OA has not been clearly defined. Furthermore, guidelines on imaging in knee OA from different authoritative bodies have not been compared in previous studies. Therefore, the present review aims to summarise existing evidence and compare guidelines on the use of different imaging modalities in evaluating knee OA. METHODS: This is a narrative review based on a search of published clinical guidelines and the PubMed database for articles published between 1 January 1990 and 31 May 2020. RESULTS: There is no broad consensus on the value of imaging in patients with typical OA presentation. If imaging is required, current evidence and clinical guidelines support the use of radiography and MRI as first- and second-line diagnostic modalities respectively. Since radiographic OA features have limited sensitivity and do not manifest in early stages, MRI is the preferred option for whole-joint evaluation in OA research. Discrepancies exist regarding the use of alternative imaging modalities including ultrasound, computed tomography and nuclear medicine. CONCLUSION: Radiography and MRI are the imaging modalities of choice. Other modalities have their respective advantages, and more research is warranted for the standardisation of image acquisition and interpretation methodology, in order to evaluate their validity, reliability and responsiveness in OA research.

Correcting severe flexion contracture with fusiform capsulectomy of posterior capsule during total knee arthroplasty.

PURPOSE: This study aimed to evaluate the safety and efficacy of fusiform capsulectomy of posterior capsule in correcting severe flexion contracture during total knee arthroplasty (TKA). METHODS: A retrospective analysis was performed in the patients who had preoperative severe flexion contracture (> 30 degrees) prior to TKA and received fusiform capsulectomy of posterior capsule during TKA between December 2013 and November 2018. Range of motion (ROM), knee functional score, forgotten joint score (FJS), post-operative complications, and radiographic results were collected and evaluated. RESULT: Twenty patients (32 knees) were enrolled in this study. The mean duration of follow-up was 27.19 ± 15.92 months. The flexion contracture improved from pre-operative 37.69 ± 11.79° to post-operative 5.78 ± 4.44° (p < 0.001), and ROM increased from pre-operative 63.50 ± 21.74° to post-operative 97.88 ± 13.20° (p < 0.001). KSS clinical score increased from pre-operative 32.94 ± 11.03 to post-operative 82.34 ± 10.73 (p < 0.001), and KSS function score increased from pre-operative 28.97 ± 18.43 to post-operative 68.75 ± 15.96 (p < 0.001). The post-operative FJS was 76.08 ± 2.14. There was no implant loosening, infection, obvious haematoma formation, resultant instability, neurovascular complications, or revision for any reasons in the cohort until the last follow-up. CONCLUSIONS: The technique of fusiform capsulectomy of posterior capsule to correct the severe flexion contracture during primary TKA is safe and effective and could provide good short-term results.

Use of a modular hip dual-mobility articulation in patients with high risk of dislocation: a relatively small-sized acetabulum in Asian patients may limit its use.

BACKGROUND: Dual-mobility hip component is widely used in Europe and North America, because it effectively reduces hip dislocation in primary and revision total hip arthroplasties. However, reports were limited on the use of dual-mobility articulation in Asian populations. PURPOSE: The aim of this retrospective study was to review the use of modular dual-mobility hip articulation in Asian patients with the high risk factor for hip dislocation. We also discussed the potential concern on the use of dual-mobility articulation in Asian patients. METHODS: From Jan 2018 to June 2019, 17 patients were included in this study. The mean age of the patients was (73.8 ± 9.5) years (range: 57-88 years). The mean size of acetabular cup and modular DM liner were (49.5 ± 3.4) mm (range, 46-58 mm) and (40.7 ± 3.4) mm (range, 38-48 mm), respectively. The mean follow-up period was (15.8 ± 3.9) months (range, 11-24 months). The primary outcome was the rate of hip dislocation. The secondary outcomes included the Harris Hip Score. Differences were considered statistically significant at p < 0.05. RESULTS: Hip dislocation, loosening, peri-prosthetic fractures, or intra-prosthetic dislocation was not found in the series. The mean preoperative and postoperative Harris Hip Scores were 42.2 ± 17.2 (range, 15-80) and 74.7 ± 13.5 (range, 52-97), respectively, giving a mean improvement of 32.5 ± 17.2 (range, 4-72). The improvement was statistically significant (p < 0.05). CONCLUSIONS: In Asian patients with high risk of hip dislocation, the use of modular dual-mobility hip component produces promising outcomes without hip dislocation, but the relatively small-sized acetabulum may limit it widespread application in other populations worldwide. TRIAL REGISTRATION: HKUCTR-2913 .

The application of close incisional negative pressure wound therapy in revision arthroplasty among asian patients: a comparative study.

INTRODUCTION: Peri-prosthetic joint infection (PJI) was one of the main causes of revision of arthroplasty. In order to reduce wound complications and surgical site infections, close incisional negative pressure wound therapy (ciNPWT) has been introduced into arthroplasty. This study was designed to review the clinical benefits of the application of ciNPWT in revision arthroplasty. METHODS: This was a single-centre retrospective comparative study approved by the Institutional Review Board. Patients, who underwent revision total knee arthroplasty or revision total hip arthroplasty at the author's institution from January 2016 to October 2019, were included in this study. The ciNPWT cohort included all eligible patients, who underwent operations from January 2018 to October 2019, with the use of ciNPWT(n = 36). The control cohort included all eligible patients, who underwent operations from January 2016 to December 2017 with the use of conventional dressing(n = 48). The incidences of wound complications were compared to both cohorts. RESULTS: There was a statistically significant difference in the rate of superficial surgical site infection (SSI) between control cohort and ciNPWT cohort (12.5% in control vs 0% in ciNPWT, p = 0.035). However, there was no statistically significance of the overall wound complication rate for both cohorts. (14.6% in control vs 8.3% in ciNPWT, p = 0.504). CONCLUSIONS: The application of ciNPWT could result in a lower rate of superficial surgical site infection when compared with conventional dressing among the patients undergoing revision total knee and total hip arthroplasties. TRIAL REGISTRATION: UW19-706.

Lessons learnt from the impact of COVID-19 on arthroplasty services in Hong Kong: how to prepare for the next pandemic?

BACKGROUND: Arthroplasty services worldwide have been significantly disrupted by the pandemic of coronavirus disease 2019 (COVID-19). This retrospective comparative study aimed to characterize its impact on arthroplasty services in Hong Kong. METHODS: From January 1 to June 30, 2020, the patients of "COVID-19 cohort" underwent elective total hip or knee replacement in Hong Kong public hospitals. The cohort was compared to the "control cohort" during the same period in 2019. Data analysis was performed to compare the two cohorts' numbers of operations, hospital admission, orthopaedic clinic attendances, and waiting time. RESULTS: A total of 33,111 patient episodes were analyzed. During the study period, the elective arthroplasty operations and hospitalizations decreased by 53 and 54%, respectively (P < 0.05). Reductions were most drastic from February to April, with surgical volume declining by 86% (P < 0.05). The primary arthroplasty operations decreased by 91% (P < 0.05), while the revision operations remained similar. Nevertheless, 14 public hospitals continued performing elective arthroplasty for patients with semi-urgent indications, including infection, progressive bone loss, prosthesis loosening, dislocation or mechanical failure of arthroplasty, and tumor. At the institution with the highest arthroplasty surgical volume, infection (28%) was the primary reason for surgery, followed by prosthesis loosening (22%) and progressive bone loss (17%). The orthopaedic clinic attendances also decreased by 20% (P < 0.05). Increases were observed in waiting time and the total number of patients on the waiting list for elective arthroplasty. CONCLUSIONS: Despite the challenges, public hospitals in Hong Kong managed to continue providing elective arthroplasty services for high-priority patients. Arthroplasty prioritization, infection control measures, and post-pandemic service planning can enhance hospital preparedness to mitigate the impact of current and future pandemics.

Combination Effect of High-Dose Preoperative and Periarticular Steroid Injection in Total Knee Arthroplasty. A Randomized Controlled Study.

BACKGROUND: Postoperative pain remains a major barrier to a patient's recovery after total knee arthroplasty (TKA). Periarticular corticosteroids in local infiltration analgesics (LIA) and high-dose intravenous corticosteroids have individually shown to improve pain control after TKA. However, potential interactions between them have not been investigated. This study aims to evaluate any combination effect of both routes of corticosteroids in TKA. METHODS: This is a double-blinded, paired, randomized controlled trial involving 1-stage bilateral TKAs. All received 16 mg of dexamethasone intravenously. One knee was randomized to receive LIA with 40 mg of triamcinolone, while the other knee receives LIA without corticosteroids. For each patient, one knee was affected by intravenous steroids only, while the other was under the combined effect of intravenous and periarticular steroids (IVPAS). Knee pain, Southampton wound scores, and functional knee scores (Knee Society Knee Score and Oxford Knee Scores) were compared between knees of the same patient. RESULTS: Forty-six patients (92 TKAs) were included. IVPAS knees showed significantly lower visual analog scale scores from day 1 to 6 weeks (P < .05) and a larger range of movement from day 2 to 4 (P < .05). IVPAS knees achieved active straight leg raise earlier than intravenous steroids (1.6 vs 2.3 days, P < .05). No differences in Southampton wound scores and functional knee scores for up to 1 year. CONCLUSION: Combining intravenous and periarticular corticosteroids improved pain control and recovery after TKA with no increase in wound complications up to 1 year.

Robotic-Arm Assistance Simplifies Hip Arthrodesis Conversion to Total Hip Arthroplasty.

Hip fusion takedown to total hip replacement is a challenging operation. Neck osteotomy and acetabular component placement are technically demanding and often require fluoroscopic guidance. Robotic arm-assisted total hip arthroplasty enhances accuracy of preoperative planning and provides navigated guidance for neck osteotomy and haptic guidance on acetabular reaming and cup implantation. Fluoroscopic guidance is replaced by real-time navigation and on-screen data. This article describes how robotic arm assistance can simplify this complex operation.