Patient-reported Outcome Measures of Revision Total Hip Arthroplasty for Prosthetic Joint Infection is not Inferior to Aseptic Revision Total Hip Arthroplasty.

INTRODUCTION: This study aims to investigate whether patients undergoing two-stage revision total hip arthroplasty (THA) for prosthetic joint infection (PJI) and one-stage revision THA for aseptic reasons have similar clinical outcomes and patient satisfaction during their post-operative follow-up. We hypothesise that the two-stage revision THA for PJI is associated with poorer outcomes as compared to aseptic revision THA. MATERIALS AND METHODS: We reviewed prospectively collected data in our tertiary hospital arthroplasty registry and identified patients who underwent revision THA between 2001 and 2014, with a minimum of two years follow-up. The study group (two-stage revision THA for PJI) consists of 23 patients and the control group (one-stage revision THA for aseptic reasons) consists of 231 patients. Patient demographics, Western Ontario and McMaster Universities Arthritis Index (WOMAC), Oxford Hip Score (OHS), Short Form-36 (SF-36) scores and patient reported satisfaction were evaluated. Student's t-test was used to compare continuous variables between the two groups. Statistical significance was defined as p <0.05. RESULTS: The pre-operative demographics and clinical scores were relatively similar between the two groups of patients. At two years, patients who underwent revision THA for PJI reported a better WOMAC Pain Score and OHS as compared to aseptic revision THA. A similar proportion of patients were satisfied with their results of surgery in both groups (p=0.093). CONCLUSIONS: Although patients who underwent revision THA for PJI had poorer pre-operative functional scores (WOMAC function and SF-36 PF), at two years follow-up, these two groups of patients have comparable post-operative outcomes. Interestingly, patients who had revision THA for PJI reported a better clinical outcome in terms of OHS and WOMAC Pain score as compared to the aseptic group. We conclude that the revision THA for PJI is not inferior to aseptic revision THA in terms of patient satisfaction and clinical outcomes.

The influence of obesity on clinical outcomes of fixed-bearing unicompartmental knee arthroplasty: a ten-year follow-up study.

AIMS: The aim of this study was to assess the influence of obesity on the clinical outcomes and survivorship ten years postoperatively in patients who underwent a fixed-bearing unicompartmental knee arthroplasty (UKA). PATIENTS AND METHODS: We prospectively followed 184 patients who underwent UKA between 2003 and 2007 for a minimum of ten years. A total of 142 patients with preoperative body mass index (BMI) of < 30 kg/m2 were in the control group (32 male, 110 female) and 42 patients with BMI of ≥ 30 kg/m2 were in the obese group (five male, 37 female). Pre- and postoperative range of movement (ROM), Knee Society Score (KSS), Oxford Knee Score (OKS), 36-Item Short-Form Health Survey (SF-36), and survivorship were analyzed. RESULTS: Patients in the obese group underwent UKA at a significantly younger mean age (56.5 years (sd 6.4)) than those in the control group (62.4 years (sd 7.8); p < 0.001). There was no significant difference in preoperative functional scores. However, those in the obese group had a significantly lower ROM (116° (sd 15°) vs 123° (sd 17°); p = 0.003). Both groups achieved significant improvement in outcome scores regardless of BMI, ten years postoperatively. All patients achieved the minimal clinically important difference (MCID) for OKS and KSS. Both groups also had high rates of satisfaction (96.3% in the control group and 97.5% in the obese group) and the fulfilment of expectations (94.9% in the control group and 95.0% in the obese group). Multiple linear regression showed a clear association between obesity and a lower OKS two years postoperatively and Knee Society Function Score (KSFS) ten years postoperatively. After applying propensity matching, obese patients had a significantly lower KSFS, OKS, and physical component score (PCS) ten years postoperatively. Seven patients underwent revision to total knee arthroplasty (TKA), two in the control group and five in the obese group, resulting in a mean rate of survival at ten years of 98.6% and 88.1%, respectively (p = 0.012). CONCLUSION: Both groups had significant improvements in functional and quality-of-life scores postoperatively. However, obesity was a significant predictor of poorer improvement in clinical outcome and an increased rate of revision ten years postoperatively.

Cost Effectiveness of Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Management of Colorectal Peritoneal Carcinomatosis.

BACKGROUND: Peritoneal carcinomatosis from colorectal cancer is a stage 4 disease for which palliative chemotherapy has traditionally been considered the mainstay of treatment. Since the development of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) by Sugarbaker, this combined method treatment has resulted in improved survival outcomes with acceptable morbidity for selected patients with peritoneal carcinomatosis. This study examined the cost effectiveness of CRS and HIPEC compared with palliative chemotherapy for patients with peritoneal carcinomatosis from colorectal cancer within the context of the Singaporean health care system. METHODS: A retrospective review of patients with peritoneal carcinomatosis from histologically proven colorectal cancer treated at the National Cancer Centre Singapore (NCCS) was conducted. RESULTS: The average cost of CRS and HIPEC per patient was S$83,680.26, and the median overall survival period was 47 months. The calculated cost per life year attained for a patient who underwent CRS and HIPEC was S$21,365.19 per life year. In comparison, the average cost of palliative chemotherapy was S$44,478.87, with a median overall survival of 9 months, and the calculated cost per life year attained for a patient in this treatment group was S$59,305.16 per life year. CONCLUSION: The findings show that CRS and HIPEC results in prolonged survival for selected patients with colorectal peritoneal carcinomatosis and a lower cost per life year attained than for the traditionally used palliative chemotherapy. It should logically be the preferred treatment of choice for selected patients with colorectal peritoneal metastasis.

Revision total knee arthroplasty for failed high tibial osteotomy and unicompartmental knee arthroplasty have similar patient-reported outcome measures in a two-year follow-up study.

AIMS: Little is known about the relative outcomes of revision of unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO) to total knee arthroplasty (TKA). The aim of this study is to compare the outcomes of revision surgery for the two procedures in terms of complications, re-revision and patient-reported outcome measures (PROMs) at a minimum of two years follow-up. PATIENTS AND METHODS: This study was a retrospective review of data from an institutional arthroplasty registry for cases performed between 2001 and 2014. A total of 292 patients were identified, of which 217 had a revision of HTO to TKA, and 75 had revision of UKA to TKA. While mean follow-up was longer for the HTO group compared with the UKA group, patient demographics (age, body mass index and Charlson co-morbidity index) and PROMs (Short Form-36, Oxford Knee Score, Knee Society Score, both objective and functional) were similar in the two groups prior to revision surgery. Outcomes included the rate of complications and re-operation, PROMS and patient-reported satisfaction at six months and two years post-operatively. We also compared the duration of surgery and the need for revision implants in the two groups. RESULTS: At two-year follow-up, both groups of patients had made significant improvement in terms of PROMs compared with pre-operative scores. PROMs and satisfaction rates were similar in the two groups. Complications requiring re-operation were significantly more frequent in the HTO group whilst more revision implants were used in the UKA group, resulting in a longer operative duration. CONCLUSION: Revision of HTO and UKA achieve similar post-operative PROMs and satisfaction. Revision of UKA more frequently requires revision components with increased operation duration but fewer complications requiring re-operation compared with revision of HTO. Cite this article: Bone Joint J 2017;99-B:1329-34.

Protecting microRNAs from RNase degradation with steric DNA nanostructures.

Tumor suppressive microRNAs are potent molecules that might cure cancer, one day. Despite the many advanced strategies for delivery of these microRNAs to the cell, there are few therapeutic microRNAs in clinical use. Progress in microRNA bioapplications is hindered by a high vulnerability of exogeneous microRNA molecules to RNase degradation that occurs in extra- and intracellular physiological conditions. In this proof-of-concept study, we use a programmable self-assembled DNA nanostructure bearing a "shuriken" shape to not only deliver but more importantly protect a tumor suppressive microRNA-145 for a sufficiently long time to exert its therapeutic effect in human colorectal cancer cells. Our DNA nanostructure harbored complementary sequences that can hybridize with the microRNA cargo. This brings the microRNA-DNA duplex very close to the core structure such that the microRNA cargo becomes sterically shielded from RNase's degradative activity. Our novel DNA nanostructure based protector concept removes the degradative bottleneck that may plague other nucleic acid delivery strategies and presents a new paradigm towards exploiting these microRNAs for anti-cancer therapy.

Outcomes and survivorship of unicondylar knee arthroplasty in patients with severe deformity.

Purpose Patients with severe deformity beyond the standard indications for unicompartmental knee arthroplasty (UKA) may be suitable and benefit from UKA. This study investigated their outcomes to determine whether good function and quality of life (QOL) can be achieved. MATERIALS AND METHODS: Fifty-three patients with severe deformity (40 patients with FFD ≥15° and 13 patients with varus deformity ≥15°, Group A) were matched with 53 patients with less severe deformities who underwent UKA (Group B/controls) in terms of age, sex, BMI and duration of follow-up. Their flexion range, Knee Society scores (KSS), Oxford knee scores (OKS) and SF-36 QOL scores were analysed pre-operatively and at 2 years. RESULTS: Group A patients were largely similar to Group B patients pre-operatively in terms of maximum flexion angle, OKS and SF-36 scores except for knee score and mental health component of SF-36. At 2 years, Group A reported largely similar results compared with Group B in all outcome scores (OKS, KSS, SF-36) and flexion angle. Post-operative mechanical alignment was better for the control group though it is not statistically significant. There were no revisions in the patients with severe pre-operative deformity at 5 years post-operatively. (Survivorship 100 % at 5 years). CONCLUSION: Selected patients with severe deformity can achieve good function and QOL with UKA if satisfactory mechanical alignment is restored. This study supports a broadening of the indications of UKA; however, further follow-up is needed to assess the longer-term durability of the operation. LEVEL OF EVIDENCE: IV.

Titanium dioxide nanomaterials cause endothelial cell leakiness by disrupting the homophilic interaction of VE-cadherin.

The use of nanomaterials has raised safety concerns, as their small size facilitates accumulation in and interaction with biological tissues. Here we show that exposure of endothelial cells to TiO2 nanomaterials causes endothelial cell leakiness. This effect is caused by the physical interaction between TiO2 nanomaterials and endothelial cells' adherens junction protein VE-cadherin. As a result, VE-cadherin is phosphorylated at intracellular residues (Y658 and Y731), and the interaction between VE-cadherin and p120 as well as ß-catenin is lost. The resulting signalling cascade promotes actin remodelling, as well as internalization and degradation of VE-cadherin. We show that injections of TiO2 nanomaterials cause leakiness of subcutaneous blood vessels in mice and, in a melanoma-lung metastasis mouse model, increase the number of pulmonary metastases. Our findings uncover a novel non-receptor-mediated mechanism by which nanomaterials trigger intracellular signalling cascades via specific interaction with VE-cadherin, resulting in nanomaterial-induced endothelial cell leakiness.

Fasciotomy and surgical tenotomy for recalcitrant lateral elbow tendinopathy: early clinical experience with a novel device for minimally invasive percutaneous microresection.

BACKGROUND: The optimal choice for intervention for recalcitrant lateral elbow tendinopathy remains unclear as various treatment modalities have documented comparable results in the literature. PURPOSE: To explore the safety, tolerability, and early efficacy of a new minimally invasive mode of treatment that delivers focused, calibrated ultrasonic energy, effectively microresecting the pathological tendon and removing only pathological tissue. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Seven male and 13 female patients aged 33 to 65 years averaging 12.5 months (range, 4-48) of failed nonoperative therapy underwent the ultrasonic microresection procedure in an outpatient clinic setting. The procedure involved a sterile, ultrasound-guided percutaneous microresection with a proprietary device (TX1) performed through a stab incision under local anesthesia. The duration of the procedure and complications of the device or procedure were assessed. Outcome parameters included patient satisfaction; visual analog scale (VAS) pain scores; Disabilities of the Arm, Shoulder and Hand (DASH) scores at 1, 3, 6, and 12 months; and ultrasound assessment at 3 and 6 months. RESULTS: The median duration for the sterile confirmatory ultrasound examination (phase 1) was 88.5 seconds (range, 39-211; SD, ±47.6), the median duration of the procedure proper (phase 2) was 10.1 minutes (range, 4.1-19.4; SD, ±3.7), and the median energy time (duration the TX1 device was activated) was 32.5 seconds (range, 18-58; SD, ±11.0). No complications were encountered. A significant improvement in VAS score (from 5.5 to 3.3; P < .001) occurred by 1 week, and significant improvements in both DASH-Compulsory (from 21.7 to 11.3; P = .001) and DASH-Work (from 25.0 to 6.3; P = .012) scores occurred by 1 month. The VAS scores further improved at 3, 6, and 12 months (from 2.0 to 1.0 to 0.50; P = .003 and .023). The DASH-Compulsory score improved significantly from 3 to 6 months (from 8.6 to 4.6; P = .003), and both the DASH-Compulsory and DASH-Work scores were sustained by 12 months. Sonographically reduced tendon thickness (19 patients), resolved or reduced hypervascularity (17 patients), and reduced hypoechoic area (18 patients) occurred by 6 months. Nineteen of the 20 patients (95%) expressed satisfaction with the procedure, with 9 patients being very satisfied with their overall experience at 6 months after the procedure, 10 patients somewhat satisfied, and 1 patient neutral. CONCLUSION: Ultrasonic microresection of diseased tissue with the TX1 device provides a focally directed, safe, specific, minimally invasive, and well-tolerated treatment for recalcitrant lateral elbow tendinopathy in an office-based or ambulatory surgical setting with good evidence of some level of efficacy in 19 of 20 patients (95%) that is sustained for at least 1 year.

Evaluation of the relationship between anteroposterior translation of a posterior cruciate ligament-retaining total knee replacement and functional outcome.

The success of total knee replacement (TKR) depends on optimal soft-tissue balancing, among many other factors. The objective of this study is to correlate post-operative anteroposterior (AP) translation of a posterior cruciate ligament-retaining TKR with clinical outcome at two years. In total 100 patients were divided into three groups based on their AP translation as measured by the KT-1000 arthrometer. Group 1 patients had AP translation < 5 mm, Group 2 had AP translation from 5 mm to 10 mm, and Group 3 had AP translation > 10 mm. Outcome assessment included range of movement of the knee, the presence of flexion contractures, hyperextension, knee mechanical axes and functional outcome using the Knee Society score, Oxford knee score and the Short-Form 36 questionnaire. At two years, patients in Group 2 reported significantly better Oxford knee scores than the other groups (p = 0.045). A positive correlation between range of movement and AP translation was noted, with patients in group 3 having the greatest range of movement (mean flexion: 117.9° (106° to 130°)) (p < 0.001). However, significantly more patients in Group 3 developed hyperextension > 10° (p = 0.01). In this study, the best outcome for cruciate-ligament retaining TKR was achieved in patients with an AP translation of 5 mm to 10 mm.

Duloxetine reduces morphine requirements after knee replacement surgery.

BACKGROUND: Multimodal analgesia is advocated for perioperative pain management to reduce opioid use and its associated adverse effects. Serotonin and norepinephrine are involved in the modulation of endogenous analgesic mechanisms via descending inhibitory pain pathways in the brain and spinal cord. An increase in serotonin and norepinephrine may increase inhibition of nociceptive input and improve pain relief. Duloxetine, a selective serotonin and norepinephrine reuptake inhibitor, has demonstrated efficacy in chronic pain conditions such as painful diabetic neuropathy and post-herpetic neuralgia. The objective of the study was to evaluate the efficacy of duloxetine in reducing morphine requirements in patients after knee replacement surgery. METHODS: Fifty patients received either two doses of oral duloxetine 60 mg (2 h before surgery and on first postoperative day) or placebo. All patients received patient-controlled analgesia with morphine for 48 h after operation. Pain and adverse effects were assessed at 0.5, 1, 2, 6, 12, 24, and 48 h after surgery on an 11-point numeric rating scale. RESULTS: Twenty-three patients in the duloxetine group and 24 patients in the placebo group completed the study. Morphine requirements during the 48 h after surgery were significantly lower in the duloxetine group [19.5 mg, standard deviation (sd) 14.5 mg] compared with the placebo group (30.3 mg, sd 18.1 mg) (P=0.017). There were no statistically significant differences between the groups in pain scores (at rest and on movement) or in adverse effects. CONCLUSIONS: Perioperative administration of duloxetine reduced postoperative morphine requirements during the first 48 h after knee replacement surgery, without significant adverse effects.

The posterior cruciate ligament: an anthropometric study in Asians and evaluation of safe limits for bony tunnel creation during reconstruction.

INTRODUCTION: Quantitative data regarding the dimensions of the posterior cruciate ligament (PCL) and its insertions have not been studied in Asians, and concerns have been raised regarding the danger of vascular injury when the bony tunnels are created during arthroscopically-assisted reconstruction. MATERIALS AND METHODS: Ten male cadavers were used in this study, incorporating dissection and procedural arms. In the procedural arm, the path of the drill bit was tracked fluoroscopically as the tibial and femoral tunnels were created during simulated reconstructive surgery, and the effect of varying knee flexion angles was studied. Fluoroscopic images were analysed using specialised image processing software. RESULTS: The mean length of the PCL at full extension was 37.7 +/- 1.9 mm, and the mean mid-substance width was 13.7 +/- 1.7 mm. The mean sagittal distance between the exit point of the tibial tunnel and the anterior surface of the popliteal artery, across all knee flexion positions, was merely 6.0 mm (range, 2.8 to 10.2 mm). This distance tended to increase with increasing knee flexion, but this was not statistically significant. The mean distance between the exit point of the femoral tunnel and the femoral artery was 51.1 mm (range, 42.1 to 59.0 mm). CONCLUSIONS: The dimensions of the PCL and its insertions in Asians do not vary greatly from those reported for Western subjects. The distance from the exit point of the tibial tunnel to the popliteal artery is very small and, although this distance increases with increasing knee flexion, the improvement in the safety margin may neither be clinically nor statistically significant. The margin of safety for drilling of the femoral tunnel is much greater.

Free transplantation of venous network pattern skin flap.

We report a patient treated by transplantation of a venous network pattern skin flap containing two superficial cutaneous veins. Through one of the veins, arterial blood passed into the capillaries, restoring circulation and ensuring survival of the flap.