Anterior tibial artery pseudoaneurysm as a rare technical complication after corrective fibular osteotomy: a case report.

INTRODUCTION: Partial fibular osteotomy has been recognized as a surgical alternative to treat medial compartment osteoarthritis of the knee. Related peroneal neuropathies are of concern among the relatively few complications after this procedure. In our clinical practice, the osteotomy level has therefore been modified to avoid the above defects. However, a rare case of vascular injury was encountered. Herein we describe an accidental anterior tibial artery pseudoaneurysm as a rare technical complication after this corrective osteotomy. CASE PRESENTATION: A 55-year-old male visited our emergency room, presenting a painful swelling over his right anterolateral shin along with surrounding ecchymosis. Thirteen days ago, he just underwent a corrective fibular osteotomy over his right painful varus knee at our institute, and was discharged after an uneventful postoperative stay. Urgent angiography revealed an out-pouching vascular lesion, pseudoaneurysm, involving his right anterior tibial artery. Prompt endovascular repair with stent insertion and balloon compression successfully stopped the persistent extravasation from the injured artery. Follow-up angiography as well as outpatient review confirmed the regression of this lesion and associated symptoms without sequelae. CONCLUSION: Although corrective fibular osteotomy is a simple surgical procedure, it is not free of complications. The suggested osteotomized level in the pertinent literature predisposes patients to certain neuromuscular deficits, which could be avoided by the modified level of osteotomy. However, our case highlights surgeons' familiarity with certain risky neurovascular structures around the osteotomy site and corresponding technical considerations. A recent surgical history along with alarming symptoms/signs should arouse clinical suspicion, aid in timely identification and make appropriate interventions for potential vascular complications.

Proximal fibular osteotomy relieves pain in spontaneous osteonecrosis of the knee: A retrospective study.

Spontaneous osteonecrosis of the knee (SONK) causes knee pain and joint motion limitation. Ischemia or insufficiency fracture may be the cause, but no consensus has been developed. Proximal fibular osteotomy (PFO) has been reported to relieve pain from osteoarthritis through medial compartment decompression. We reviewed the effect of this procedure on medial compartment SONK patients and explored clinical and radiological results. Since January 2018 to January 2020, the data of 12 knees (8 right and 4 left) from 11 SONK patients (9 women and 2 men) who received PFO were analyzed. The average age was 61.5 years. The diagnosis of SONK was established through weight-bearing anterior-posterior radiographs or magnetic resonance imaging (MRI). Visual analog scale (VAS) scores, Oxford knee score (OKS), Femorotibial angle (FTA), medial joint space, and lateral joint space were documented preoperatively and at follow up visits. Outcome assessment for the clinical and radiographic data was reviewed at 12- and 24-month follow-up visits. The mean follow up period was 33 months. All patients were able to walk with or without cane assistance the day after surgery. Both VAS score and OKS (preoperative: 6.6 ± 0.9 and 24.7 ± 3.8, respectively) improved significantly at the 12-month follow-up, and to 24-month follow-up (3.6 ± 1.3 and 35.6 ± 4.5, respectively, P < .05). Medial joint space ratio increased from 0.36 to 0.50 (P < .05). Changes of FTA were insignificant at any point of follow up. Four patients underwent follow-up MRI, and a decrease in the osteonecrotic area was clearly observed in 2 patients. By achieving medial knee decompression, PFO allowed quick weight-bearing recovery, pain relief, and improvement in knee function in SONK patients.

Surface Modification of Direct-Current and Radio-Frequency Oxygen Plasma Treatments Enhance Cell Biocompatibility.

The sand-blasting and acid etching (SLA) method can fabricate a rough topography for mechanical fixation and long-term stability of titanium implant, but can not achieve early bone healing. This study used two kinds of plasma treatments (Direct-Current and Radio-Frequency plasma) to modify the SLA-treated surface. The modification of plasma treatments creates respective power range and different content functional OH groups. The results show that the plasma treatments do not change the micron scale topography, and plasma-treated specimens presented super hydrophilicity. The X-ray photoelectron spectroscopy (XPS)-examined result showed that the functional OH content of the RF plasma-treated group was higher than the control (SLA) and DC treatment groups. The biological responses (protein adsorption, cell attachment, cell proliferation, and differentiation) promoted after plasma treatments, and the cell responses, have correlated to the total content of amphoteric OH groups. The experimental results indicated that plasma treatments can create functional OH groups on SLA-treated specimens, and the RF plasma-treated SLA implant thus has potential for achievement of bone healing in early stage of implantation.

Factors affecting the outcomes of modified tension band wiring techniques in transverse patellar fractures.

INTRODUCTION: Modified tension band wiring has been widely used to treat transverse patellar fractures. However, few studies have evaluated the clinical outcomes using different methods of Kirschner wire bending, location of the tension band, and depths of Kirschner wires. Thus, we tried to clarify these factors according to our clinical outcomes. PATIENTS AND METHODS: This retrospective cohort study recruited consecutive patients underwent surgical fixation for patellar fractures using modified tension band technique between January 2010 and December 2015. Different factors in this procedure, including the bending manner of the Kirschner wires, their depth, and location of the tension band with respect to the superior and inferior border of the patella were recorded and analysed. The primary outcome was early loss of fixation. The secondary outcomes were minor loss of reduction, implant breakage, deep infection, and the need for implant removal. RESULTS: This study included 170 patients with patellar fractures. Regarding the bending method, similar results were obtained with bilaterally or proximally bent Kirschner wires. Regarding length, the tension band was placed closely (within 25% of the patella length) in 124 patients and distantly in 46 patients. The rates of loss of reduction and implant breakage were significantly higher in the distantly placed tension bands. Regarding depth, 37 patellar fractures were fixed with the Kirschner wires at the superficial one third of the patellae while the K- wires at the middle layer of patella were used in the remaining 133 patellar fractures. A significantly higher rate of minor loss of reduction was obtained using the superficial Kirschner wires. CONCLUSION: The modified tension band technique for transverse patella fractures provides favourable clinical outcomes, with low failure (5%) and infection (2%) rates. Implant irritation is the major complication, and almost half of cases require implant removal. The location of the tension band with respect to the superior and inferior border of the patella plays an important role in clinical outcomes. Placing the wire close to the patella may prevent major loss of reduction and implant breakage. Superficially placed Kirschner wires also affect clinical outcomes by increasing the rate of minor loss of reduction.

Frequent Dental Scaling Is Associated with a Reduced Risk of Periprosthetic Infection following Total Knee Arthroplasty: A Nationwide Population-Based Nested Case-Control Study.

Oral bacteremia has been presumed to be an important risk factor for total knee arthroplasty (TKA) infection. We aimed to investigate whether dental scaling could reduce the risk of TKA infection. A nested case-control study was conducted to compare 1,291 TKA patients who underwent resection arthroplasty for infected TKA and 5,004 matched controls without infection in the TKA cohort of Taiwan's National Health Insurance Research Database (NHIRD). The frequency of dental scaling was analyzed. Multiple conditional logistic regression was used to assess the frequency of dental scaling and the risk of TKA infection. The percentage of patients who received dental scaling was higher in the control group than in the TKA infection group. The risk for TKA infection was 20% lower for patients who received dental scaling at least once within a 3-year period than for patients who never received dental scaling. Moreover, the risk of TKA infection was reduced by 31% among patients who underwent more frequent dental scaling (5-6 times within 3 years). Frequent and regular dental scaling is associated with a reduced risk of TKA infection.

Fabrication of gelatin-strontium substituted calcium phosphate scaffolds with unidirectional pores for bone tissue engineering.

This study fabricated homogeneous gelatin-strontium substituted calcium phosphate composites via coprecipitation in a gelatin solution. Unidirectional porous scaffolds with an oriented microtubular structure were then manufactured using freeze-drying technology. The resulting structure and pore alignment were determined using scanning electron microscopy. The pore size were in the range of 200-400 µm, which is considered ideal for the engineering of bone tissue. The scaffolds were further characterized using energy dispersive spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. Hydroxyapatite was the main calcium phosphate compound in the scaffolds, with strontium incorporated into the crystal structure. The porosity of the scaffolds decreased with increasing concentration of calcium-phosphate. The compressive strength in the longitudinal direction was two to threefold higher than that observed in the transverse direction. Our results demonstrate that the composite scaffolds degraded by approximately 20 % after 5 weeks. Additionally, in vitro results reveal that the addition of strontium significantly increased human osteoblastic cells proliferation. Scaffolds containing strontium with a Sr-CaP/(gelatin + Sr-CaP) ratio of 50 % provided the most suitable environment for cell proliferation, particularly under dynamic culture conditions. This study demonstrates the considerable potential of composite scaffolds composed of gelatin-strontium-substituted calcium phosphate for applications in bone tissue engineering.

Incidence and risk of venous thromboembolism among Taiwan osteoporotic fracture population under osteoporosis pharmacological treatments.

CONTEXT: There was no clear evidence for the association between oral bisphosphonates or raloxifene and venous thromboembolism (VTE). There might also be ethnic differences in VTE risk. OBJECTIVE: The purpose of this study was to compare the incidence and risk of VTEs for different classes of osteoporosis drugs in the Taiwanese osteoporotic fracture population. DESIGN: This was a retrospective cohort study from 2003 to 2007, with up to 6 years follow-up. SETTING: Enrollees were participants in Taiwan National Health Insurance. PATIENTS: PATIENTS older than 50 years who had vertebral or hip fractures and were new to osteoporosis therapy were recruited. INTERVENTION: PATIENTS were classified into the alendronate, calcitonin, or raloxifene group according to exposure after follow-up. MAIN OUTCOME MEASURE: The primary outcome of our study was all incident VTEs, including deep vein thrombosis and pulmonary embolism. Cox proportional hazard models were used to compare the relative VTE risk among alendronate, raloxifene, and calcitonin groups under an on-treatment scenario. RESULTS: There were 25 443, 9642, and 31 900 patients in the alendronate, raloxifene, and calcitonin groups, and the mean age was 74.5 years (SD, 9.6). The incidence of VTE in the alendronate, raloxifene, and calcitonin groups was 11.2, 8.5, and 18.8 per 10 000 person-years. Results from Cox analyses showed that alendronate or raloxifene recipients did not have a higher risk for VTE than calcitonin recipients (adjusted hazard ratio for alendronate, 0.84; 95% confidence interval, 0.47-1.51; adjusted hazard ratio for raloxifene, 0.64; 95% confidence interval, 0.33-1.28). CONCLUSION: This retrospective analysis found that the incidence of VTE in Taiwanese patients with osteoporosis was low, and the risk of VTE was similar across alendronate, raloxifene, and calcitonin recipients in patients with osteoporotic fractures who were new to osteoporosis therapy.

The severity of the long head biceps tendinopathy in patients with chronic rotator cuff tears: macroscopic versus microscopic results.

BACKGROUND: This study investigated the histopathology of the long head of biceps (LHB) tendon and correlated the findings with the macroscopic appearances of the LHB and the size of rotator cuff tears (RCTs) in patients with chronic RCTs. METHODS: We compared biopsy specimens from LHBs in 34 patients with chronic RCTs and grossly normal LHBs in 8 patients undergoing shoulder hemiarthroplasty (controls). Duration of preoperative symptoms, the severity of RCTs, and macroscopic appearance of LHBs were recorded, classified, and compared with the histologic grading and apoptosis index of terminal deoxynucleotide transferase-mediated biotin-deoxy uridine triphosphate nick-end labeling (TUNEL) assays of LHBs. RESULTS: In the RCT group, there were 8 partial-thickness tears with 5 macroscopic LHB lesions, 12 full-thickness tears with 8 macroscopic LHB lesions, and 14 massive tears with 13 macroscopic LHB lesions. There were 6 LHB subluxations. However, the macroscopic grading and the symptom duration were not correlated with the severity of the histology. In patients with massive tears, no matter what the macroscopic appearance of the LHB, the proportion of end-stage (grade 4) histologic LHB tendinopathy significantly increased (85.7%, P < .05) compared with patients with other types of RCTs. There was a consistently high incidence of advanced LHB histology (grade 3 or higher) in each classification of RCTs (75.0%-100.0%). The 8 patients in the control group showed milder histopathology (grade 1 or 2). The apoptosis index significantly increased as the tendinopathy progressed (P < .05). CONCLUSIONS: The macroscopic pathology of LHB may not fully reflect the severity of tendinopathy, and the coexisting size of RCTs plays a role in the severity of LHB tendinopathy.

Engineering three-dimensional structures using bio-inspired dopamine and strontium on titanium for biomedical application.

The excellent mechanical properties and chemical stability of titanium and its alloys have led to their wide use as a material for dental and orthopaedic implants. However, the bio-inert nature of these materials must be overcome to enhance cell affinity and cell function following implantation. Effective implants require strong interfacial bonding, mechanical stability, osteoblast attachment, enhanced spreading and growth during early stages, and induced differentiation and mineralization in later stages. This study developed an organic-inorganic multilayer coating process for the modification of titanium implants in order to improve cell responses. A three-dimensional structure comprising strontium and micro-arc oxidized (MAO) titanium was covered with a film of poly(dopamine) to form a multilayer coating. The titanium surface formed a uniform hydrophilic oxide coating, which was firmly adhered to the surface. The poly(dopamine) film facilitated the initial attachment and proliferation of cells. Cell differentiation was enhanced by the release of strontium from the coatings. Our results demonstrate the efficacy of the proposed coating process in enhancing the multi-biological function of implant surfaces.

Comparative effectiveness of osteoporosis drugs in preventing secondary nonvertebral fractures in Taiwanese women.

CONTEXT: The evidence for relative effectiveness of osteoporosis drugs in secondary prevention of nonvertebral fractures was unclear and could not be extrapolated to the Asian population. OBJECTIVE: The objective of the study was to compare the relative effectiveness of different classes of osteoporosis drugs in secondary prevention of nonvertebral fractures in Taiwanese women. DESIGN: This was a retrospective cohort study from 2003 to 2007, with up to 6 years of follow-up. SETTING: The study included enrollees in Taiwan National Health Insurance. PATIENTS: Patients older than 50 years, with vertebral/hip fracture and were new to osteoporosis therapy, were recruited. INTERVENTION: Patients were classified into the alendronate, calcitonin, or raloxifene group, according to their exposure after follow-up. MAIN OUTCOME MEASURE: The primary outcome of our study was the risk of incident nonvertebral fracture (hip, humerus, or radius fractures). A multivariate Cox proportional hazard model adjusted for fracture risk factors was used to compare the relative fracture risk among three treatment groups under on-treatment scenarios. Propensity score-matched hazard ratios were examined, and interactions between fracture incidence and patients' compliance were investigated as well. RESULTS: There were 19 840, 9534, and 25 483 patients in the alendronate, raloxifene, and calcitonin groups, respectively. The fracture rates were highest in calcitonin recipients (4.57 per 100 person-years), followed by raloxifene and alendronate. Results from Cox analyses showed raloxifene (hazard ratio 1.47; 95% confidence interval 1.29-1.67) and calcitonin (hazard ratio 1.51; 95% confidence interval 1.29-1.75) had higher nonvertebral fracture risks as compared with alendronate. The risk differences were more pronounced in compliant patients. CONCLUSION: We found alendronate users had the lowest secondary nonvertebral fracture risk, as compared with raloxifene and calcitonin users. Consistent results were found in a series of sensitivity analyses.

Kinematic analysis of leg alignment during conventional versus navigated total knee arthroplasty: initial results of a prospective study.

Current kinematic navigation systems provide real-time spatial analyses of leg alignments during total knee arthroplasty (TKA) instead of delayed radiographic verification after surgery. A prospective study was conducted to investigate leg alignments of TKAs that underwent different surgical guidance [intramedullary (IM) jig-based vs. navigation-assisted] using a kinematic navigation system. Since May 2007, patients admitted for primary TKA were considered for inclusion. Within 6 months, 38 sets of intraoperative analyses on the operated legs have been performed. Excluding seven unreliable data sets, 15 conventional IM jig-based TKAs and 16 navigation-assisted TKAs were available. The leg alignments in maximum knee extension were retrieved for comparison. Although similar final coronal alignments were accurately achieved in both groups (0.21 valgus in the IM group vs. 0.17 valgus in the NA group, p=0.993), a more flexed sagittal axis was constructed with conventional IM jigs (1.93 flexion in the IM group vs. 0.58 extension in the NA group, p<0.05). The study suggests that comparable coronal precision could be achieved with conventional IM jigs by trained surgeons, although computer-assisted navigation is a documented method to restore accurate alignment. Different sagittal alignments observed in this study indicate the inherent discrepancy between different surgical guides as well as their according concepts.

[Reducing blood preparation for total knee arthroplasty: a practical approach].

BACKGROUND & PROBLEMS: The rate of allogenic blood preparation for an elective total knee arthroplasty (TKA) has been as high as 100% at our institute. However, most (76.2%) of these preparations were wasted. PURPOSE: This project worked to reduce unnecessary blood preparations for this elective procedure and reduce resource expenditures. RESOLUTIONS: Key issues identified as requiring resolution included: Uncertainty regarding urgent transfusion need, insufficient preoperative evaluation of high risk patients, and the use of outdated clinical pathways. Measures taken to overcome these issues included redefining transfusion triggers using relevant empirical data as conclusive evidence and building a general consensus within the medical team while acquiring practical support from decision makers. A more comprehensive assessment process for identifying risk factors was developed by reviewing and assessing the prior experiences of inpatients; New standard procedures for blood preparation and transfusion were issued; and related clinical pathways were updated with supplementary measures. RESULTS: After project implementation, the blood preparation rate declined significantly from 100% to 10.2%. The rate of effective transfusion rate rose from 23.8% to 76.2%. CONCLUSIONS: This project combined various medical professions to propose practical improvements that effectively access peer support. We recommend applying this model in all care units to ensure patient safety and lower medical costs while developing a more effective policy for blood transfusion.

An effective method to reduce ischemia time during total knee arthroplasty.

BACKGROUND/PURPOSE: Because of controversy regarding timing of tourniquet release during total knee arthroplasty (TKA), a closed arthrotomy as a tamponade for effective hemostasis was used to save ischemia time. The study was to verify the safety and efficacy on clinical issues. METHODS: A prospective cohort study was conducted on 72 consecutive unilateral primary TKAs. They were divided into two groups according to different timing of tourniquet release. The study group was composed of 36 index procedures with an intra-operative release after a tight arthrotomy closure; while the remaining 36 TKAs with a tourniquet application throughout the procedure comprised the comparative group. In all operations, no drain was used to augment the intra-articular tamponade. RESULTS: In the study group, the tourniquet time was significantly shorter (p<0.001), and thus ischemic duration and perioperative blood loss were reduced. The postoperative course was similar on the basis of analgesics consumption and inpatient stay, but better earlier functional recovery as well as subjective performance was observed at early postoperative follow-ups. CONCLUSIONS: The results suggest that a closed tamponade with arthrotomy closure and drainage avoidance is an effective hemostasis to reduce ischemia time during TKAs.

Effects of tourniquet use on blood loss and soft-tissue damage in total knee arthroplasty: a randomized controlled trial.

BACKGROUND: Although tourniquets are widely used in total knee arthroplasty, their effectiveness in reducing blood loss and their influence on the postoperative course remain unclear. Tourniquet-related soft-tissue damage is a related concern. We performed a prospective, randomized, controlled trial to clarify the effect of tourniquets in total knee arthroplasty. METHODS: Seventy-two patients undergoing total knee arthroplasty were randomly allocated to a tourniquet or non-tourniquet group. Blood loss and changes in C-reactive protein, creatine phosphokinase, and other indicators of soft-tissue damage were monitored preoperatively and postoperatively on Days 1, 2, and 4. Thigh pain, knee pain, limb swelling, rehabilitation progress, and hospital stays were also recorded for comparison. RESULTS: Patients in the tourniquet group showed smaller decreases in hemoglobin (mean and standard deviation, 2.6 ± 0.9 versus 3.7 ± 1.3 g/dL) and hematocrit (7.6% ± 2.8% versus 10.4% ± 4.0%), less calculated blood loss (303 ± 119 versus 423 ± 197 mL), and smaller increases in C-reactive protein (peak value, 175 ± 55 versus 139 ± 75 mg/dL) and creatine phosphokinase (peak value, 214 ± 89 versus 162 ± 104 U/L) compared with those in the non-tourniquet group. There was slightly less postoperative pain in the non-tourniquet group. There were no significant differences between the groups in terms of swelling, rehabilitation progress, or hospital stays. CONCLUSIONS: The use of a tourniquet during total knee arthroplasty was effective for reducing blood loss and avoiding excessive postoperative inflammation and muscle damage. The use of a tourniquet was related to slightly more postoperative pain but did not affect postoperative recovery.

Delayed superficial femoral artery pseudoaneurysm following distal femoral shaft fracture: a case report.

A 69-year-old man presented with an expanding tissue mass over the medial aspect of his left thigh 6 weeks after a fracture of the distal femur shaft. Imaging studies confirmed a rare traumatic pseudoaneurysm of the superficial femoral artery. For the massive hematoma and persistent exsanguinating hemorrhage, staged interventions were taken. First, the pseudoaneurysm was hemodynamically isolated with an endovascular stent-graft placement. Subsequent surgical exploration and aneurysmectomy were performed later for the evacuation of the formed hematoma and the relief of the resultant compressive symptoms. Because traumatic pseudoaneurysm can have an insidious onset and delayed presentation, surgeons should consider the possible complication even after initial fracture fixation.

Tourniquet use in total knee arthroplasty: a meta-analysis.

PURPOSE: The use of an intraoperative tourniquet for total knee arthroplasty (TKA) is a common practice. However, the effectiveness and safety are still questionable. A systematic review was conducted to examine that whether using a tourniquet in TKA was effective without increasing the risk of complications. METHODS: A comprehensive literature search was done in PubMed Medicine, Embase, and other internet database. The review work and the following meta-analysis were processed to evaluate the role of tourniquet in TKA. RESULTS: Eight randomized controlled trials and three high-quality prospective studies involving 634 knees and comparing TKA with and without the use of a tourniquet were included in this analysis. The results demonstrated that using a tourniquet could decrease the measured blood loss but could not decrease the calculated blood loss, which indicated actual blood loss. Patients managed with a tourniquet might have higher risks of thromboembolic complications. Using the tourniquet with late release after wound closure could shorten the operation time; whereas early release did not show this benefit. CONCLUSIONS: The current evidence suggested that using tourniquet in TKA may save time but may not reduce the blood loss. Due to the higher risks of thromboembolic complications, we should use a tourniquet in TKA with caution.

Blood loss after minimally invasive total knee arthroplasty: effects of imageless navigation.

A prospective cohort study of 100 patients undergoing primary minimally invasive total knee arthroplasty was carried out to determine blood loss after this procedure and to examine the efficacy of navigation on blood saving. The patients were divided into two groups according to the surgical technique, and underwent either computer-assisted navigation or manual procedures. All operations were performed by a single surgeon using an identical approach. To minimize blood loss, an intraoperative tourniquet was used, but no postoperative drainage was applied. Although the mean surgical time was longer in the navigated group than in the manual group (119.2 vs. 90.9 min; p < 0.001), the reductions in hemoglobin level (1.40 vs. 1.38 g/dL; p = 0.642) and calculated blood loss (470.77 vs. 482.73 mL; p = 0.796) were similar in both groups. Four patients in both groups required blood transfusion. With minimally invasive techniques and drainage avoidance, our study suggests that the blood loss after minimally invasive total knee arthroplasty was not significantly affected by the use of imageless navigation.

Non-drainage is better than 4-hour clamping drainage in total knee arthroplasty.

The role of wound drainage in total knee arthroplasty (TKA) is controversial. The use of drainage was believed to be effective in decreasing hematoma formation, but it inevitably increases bleeding because the tamponade effect of a closed and undrained wound is eliminated. Clamping the drain tube in the first 4 hours after TKA can temporarily recreate a tamponade effect for bleeding control. Previous studies compared the clamping drainage with the conventional drainage method but not with non-drainage. Some current studies have shown that drainage in TKA is not necessary. Thus, we conducted a study to compare the outcomes between the patients with temporarily clamping drainage and without drainage.One hundred consecutive patients undergoing primary TKA were included. Change of hemoglobin, blood transfusion, use of narcotics, postoperative wound dressing, length of hospital stay, and range of motion were recorded. The drain-clamping group demonstrated more postoperative hemoglobin loss and a longer hospital stay, and gained no benefit compared with the non-drain group. Therefore, we concluded that despite clamping for 4 hours after TKA, the drain was still of no use. We would not recommend using a draining system routinely after TKA.

Argon-plasma-treated chitosan: surface characterization and initial attachment of osteoblasts.

Chitosan is a biocompatible, biodegradable and non-toxic material. It is also an advanced material used for wound dressings, drug and gene delivery, and tissue engineering. In this study, we treated chitosan film with argon plasma and characterized both its physical and chemical properties. We found that argon plasma increased nano-scale roughness and introduced a carbonyl group to the chitosan surface. Meanwhile, the contact angles also decreased as the duration of the plasma treatment on chitosan was prolonged, indicating that the increased roughness and carbonyl group promote the hydrophilicity of the chitosan film surface. Moreover, the number of osteoblasts adhering to chitosan films increased and their morphology became flatter with longer plasma treatments. In conclusion, this study first demonstrates that plasma treatment on chitosan exerting surface-property change is capable of triggering the initial attachment of osteoblasts to chitosan surfaces.

Temporary drainage clamping after total knee arthroplasty: a meta-analysis of randomized controlled trials.

Drainage-clamping methods are thought to be effective in reducing blood loss after total knee arthroplasty (TKA). We conducted a systematic review to examine if these methods were effective without increasing the risk of complications. After a comprehensive search, 6 randomized controlled trials involving 603 knees and comparing clamping drainage and the immediate release of the drain after elective TKA were included in this analysis. The results demonstrated that drainage clamping could decrease the volume of drainage, but only clamping for no less than 4 hours could reduce the true blood loss. There was no significant difference between the 2 groups regarding blood transfusion, postoperative range of motion, incidence of thromboembolic events, and wound complications. The current evidence cannot confirm the advantage of clamping drainage after TKA.