Incidence and preventive treatment for deep vein thrombosis with our own preventive protocol in total hip and knee arthroplasty.

The aim of the present study was to investigate the perioperative and postoperative incidence of deep vein thrombosis (DVT) and validate the effectiveness of our own preventive treatment protocol for venous thromboembolism (VTE) occurrence in lower extremity arthroplasty patients. The subjects were 1,054 patients (mean age: 74.3 years) who underwent total hip arthroplasty (THA) or total knee arthroplasty (TKA) at our institutions between April 2014 and March 2017. We examined the frequencies of pre- and post-operative DVT by lower extremity Doppler images, and the incidence rate at proximal or distal regions as well as that according to preoperative DVT status were evaluated. Preoperative DVT was detected in 6.5% (69 cases) of our cohort and those were located 1.4% (15 cases) at proximal and 5.1% (54 cases) at distal regions. A significantly higher rate of postoperative DVT development was observed in preoperative DVT+ THA patients (P = 0.0075), but not in TKA patients only with a higher tendency (P = 0.56). The overall incidence of DVT up to 2 weeks after surgeries was 27.3% (288 cases); however, the rate in proximal femur regions was suppressed to 2.8% (30 cases), and there was no symptomatic pulmonary thromboembolism (PTE) case. The results demonstrated the importance of regular Doppler examination for early detection of postoperative DVT occurrence and the following immediate treatment initiation. Our own VTE preventive treatment protocol could reduce the development of proximal DVT, and the periodic monitoring as well as prompt treatment might prevent the fatal PTE. osteoarthritis (OA), rheumatoid arthritis (RA).

Short-term clinical outcomes of primary total knee arthroplasty with a new-type kinematic retaining implant: A comparison with preexisting cruciate retaining prosthesis.

Despite the success of total knee arthroplasty (TKA), current implant designs could not consistently restore the physiological knee kinematics, especially in cruciate-retaining (CR) implants. This study aimed to investigate the short-term clinical outcomes, particularly patient satisfaction, of primary TKA employing a new-type kinematic retaining (KR) implant. We analyzed 149 cases applied the KR implant at our institutions during June 2017 to May 2019. The effectiveness of this implant design was compared with another CR one (171 cases). Both groups underwent primary TKA in the same period and all patients completed 2 years of follow-up. Perioperative changes in range of motion (ROM), Knee Score, function score, and patient satisfaction by Forgotten Joint Score-12 (FJS-12) method were evaluated. Postoperative ROM, Knee Score, and function score were significantly improved at 1 year after surgeries and maintained for another year in both KR and CR groups. The improvement rate of ROM in KR group (108.1%) was substantially higher than that in CR (104.5%), even 4% increase could have affected patients' satisfaction in a real-world setting. Regarding the patient satisfaction, such 4 items as climbing stairs, walking on a bumpy road, doing housework or gardening, and taking a walk or hiking were significantly enhanced in KR cases compared to CR. There were no loosening or revision cases and the short-term survivorships of both implants were 100%. In addition, there has been no case of obvious complications in both groups during and after surgeries. The results of the present study suggest that this novel KR prosthesis can reproduce physiological knee kinematics, recover its functions, and contribute to pain relief after TKA. TKA procedure using the KR implant should be a good surgical option to improve postoperative outcomes.

Relationship between Stress Shielding and Optimal Femoral Canal Contact Regions for Short, Tapered-Wedge Stem Analyzed by 2D and 3D Systems in Total Hip Arthroplasty.

Although tapered-wedge short stem has been widely employed with its availability for minimally invasive surgeries in total hip arthroplasty (THA), post-operative stress shielding matter remains unresolved in cementless procedures. This study aimed to clarify the most optimal femoral canal contact regions of the stem design taking stress shielding incidence into consideration. This investigation included 60 joints from 60 patients (mean age at operation: 65.9 years), of which follow-up duration after primary THA had been more than 2 years. Frequencies of spot welds, subsidence, and stress shielding were examined 2 years after surgery. The most suitable femoral canal contact regions were evaluated by plain radiograph (2D) and 3D-computed tomography analyses according to Nakata's division for fitting manners. Spot welds were observed in 38 cases (63.3%), and no subsidence case was seen. Respective number of stress shielding cases, based on Engh's classification, categorized as degree 0, 1, and 2, were 2 (3.3%), 31 (51.7%), and 27 (45.0%), while no cases for degree 3 or 4 were found. When assessed by 3D fitting analysis, 27 cases of stress shielding degree 2 were constituted by 13/42 cases of mediolateral (ML) fit, 2/4 cases of flare fit, and 12/14 cases of multi point fit. In 42 cases of ML fitting, stem contact rate of the most proximedial region in stress shielding degree 0 and 1 was significantly higher compared to stress shielding degree 2 cases. Meanwhile, the rates of distal regions were significantly lower or absent in stress shielding degree 0 and 1 cases. The initial fixation of this stem design was very good in our cohort regardless of fitting manners. This study successfully revealed that ML fitting with femoral component, especially the most proximedial calcar site restricted fitting, would be optimal for reducing stress shielding occurrence in cementless short, tapered-wedge stem THA. Thus, the ideal stem contact region should be considered during THA procedures in light of the reduction of stress shielding development.

Short- to Mid-Term Clinical Outcomes of Posterior-Stabilized Cementless Total Knee Arthroplasty with Trabecular Metal Components.

OBJECTIVE: This study aimed to evaluate the short- to mid-term clinical results of posterior-stabilized trabecular metal total knee arthroplasty (TKA) with cementless fixation of all components and investigate the radiographic changes of tibial and patellar components and cut bone surfaces over time. METHODS: We retrospectively collected the data of 128 knees from 88 consecutive patients who had undergone initial TKA with NexGen LPS-Flex TM implants. A total of 66 knees from 45 patients (mean ± standard deviation age: 70.3 ± 7.5 years) met the selection criteria, which had been employed cementless fixation of all parts and at least 3 years of postoperative follow-up duration. Clinical evaluations included range of motion, conventional knee score, function score, postoperative complications, and revision. For radiological evaluations, the bone contact surface of each implant was divided into 7 zones for tibial component and 2 zones for patellar component. Each region was examined immediately after surgery, at 6 and 12 months, and then every year afterwards. RESULTS: The mean observation period of 45 subjects was 4.2 years. Adequate fixation of tibial components was maintained during follow-up, although the patellar components of 2 knees required revision after repeated falls. No loosening was observed in any implants. The initial gap in tibial components disappeared in all knees, and a reactive line remained in 4 knees. There were no revisions, except for 2 cases, which were ascribed to patellar component fracture caused by repeated falls. CONCLUSION: Cementless posterior-stabilized trabecular metal TKA appears to be a good surgical option. Longer-term examination for revision cases is required to validate our results.

The incidence and risk factor of deep venous thrombosis after arthroscopically assisted anterior cruciate ligament reconstruction.

PURPOSE: To retrospectively analyze the incidence and risk factors of deep venous thrombosis (DVT) detected by ultrasonography after arthroscopically assisted Anterior Cruciate Ligament Reconstruction (ACLR). METHODS: We retrospectively reviewed medical records of arthroscopically assisted ACLR surgery performed at our institution between 2012 and 2015. Revision ACLR, bone patella tendon bone (BTB) graft reconstruction, and concomitant multiple ligament reconstructions were excluded. We performed a standardized double-bundle reconstruction procedure using hamstrings graft for ACLR. All patients routinely received DVT screening by using venous ultrasonography on postoperative day 7 from 2012 to 2013, and postoperative days 7 and 14 from 2014 to 2015. The prevalence of DVT was calculated and clinical factors such as age, gender, Body Mass Index (BMI), operative time, and duration of tourniquet application were evaluated in relation to the risk factor of DVT. RESULTS: Two hundred and fifty-six patients (129 men and 127 women) with a mean age of 28.9 were enrolled. Sixteen patients (6.6%) were detected with DVT on postoperative day 7. Among 146 patients who received venous ultrasonography on both postoperative days 7 and 14, DVT were detected in five additional patients on postoperative day 14. In a total of 21 patients who were diagnosed with DVT, two were proximal, the remaining 19 were distal, and no patient had progressed to pulmonary embolism (PE). In terms of predisposing factors for developing DVT on postoperative day 7, only age ≥30 showed a statistically significant higher risk of DVT (P = 0.03). CONCLUSION: Incidence of DVT after ACLR detected by ultrasonography on postoperative day 7 was 6.6%. Patients aged ≥30 years have a potentially higher risk for developing DVT. Great care for DVT should be taken if prolonged immobilization is applied after ACLR surgery. LEVEL OF EVIDENCE: Level Ⅳ.

Chondroitin sulfate synthase 1 expression is associated with malignant potential of soft tissue sarcomas with myxoid substance.

The glycosyltransferases chondroitin sulfate synthase 1 (CHSY1) and exostoses-like 3 (EXTL3) specifically function in biosynthesis of the glycans chondroitin sulfate and heparan sulfate, respectively. Although these glycans play important roles in pathogenesis of various tumors, their significance in soft tissue sarcoma remains unknown. Here, we asked whether CHSY1 or EXTL3 expression correlates with malignant potential of soft tissue sarcomas with myxoid substance. To do so, we examined 40 samples representing specific types, including 12 cases of myxoid liposarcoma, 14 of myxofibrosarcoma, 12 of malignant peripheral nerve sheath tumor, and 2 of low-grade fibromyxoid sarcoma. We performed immunohistochemistry with anti-CHSY1 and anti-EXTL3 antibodies and compared enzyme expression levels with tumor histologic grade as assessed by the Fédération Nationale des Centres de Lutte Contre le Cancer classification and with patient 5-year survival rate. CHSY1 and EXTL3 were expressed in 72.5% and 32.5% of all tumors, respectively. Notably, CHSY1 was strongly expressed in myxofibrosarcoma and malignant peripheral nerve sheath tumor compared with other tumors and significantly associated with higher- rather than lower-grade tumors (P < .01). High expression of CHSY1 was also significantly associated with poorer patient outcomes (P = .031) and higher stages assessed by American Joint Committee on Cancer staging system (P = .004). By contrast, EXTL3 expression was not correlated with histologic grade or patient prognosis. We conclude that CHSY1 expression is closely associated with malignant potential of soft tissue sarcomas with myxoid substance.

Intraosseous neurilemmoma of the proximal ulna.

INTRODUCTION: Neurilemmoma is a benign nerve sheath neoplasm commonly located in the soft tissue. Intraosseous neurilemmoma is rare, constituting less than 1% of primary bone tumors. PRESENTATION OF CASE: A 21 year-old woman was presented with left elbow pain of 1-month duration. Plain radiographs showed a well-defined, lytic and expansile lesion of the proximal ulna. Computed tomography revealed cortical destruction and soft tissue extension. Because the tissue of origin for the tumor was uncertain, an open biopsy was performed. The specimens demonstrated a benign spindle cell tumor suggestive of a neurilemmoma, similar to a soft tissue neurilemmoma. The diagnosis of intraosseous neurilemmoma was established. Marginal excision of the soft tissue component and curettage of the lesion in the bone were performed. After 3.5 years of follow up, there is no clinical or radiographic finding to suggest any recurrence. DISCUSSION: The major site of intraosseous neurilemmoma is the mandible. Occurrence in the long bone is particularly rare. Only two cases of intraosseous neurilemmoma involving the bones around the elbow have been reported to our knowledge; these cases arose in the distal humerus. We describe the first case of intraosseous neurilemmoma of the proximal ulna of the left elbow. The recommended treatment is conservative resection and bone grafting, as malignant change is extremely rare. CONCLUSION: Although very rare, intraosseous neurilemmoma should be taken under consideration in the differential diagnosis of painful, radiographically benign-appearing osseous tumor around the elbow.

Mandibuloacral dysplasia and a novel LMNA mutation in a woman with severe progressive skeletal changes.

A 56-year-old Japanese woman with mandibuloacral dysplasia and type A lipodystrophy is described. Mutation analysis identified a homozygous missense mutation (1585G > A) in exon 9 of the LMNA gene that replaces well-conserved residue alanine at position 529 to threonine (A529T). The woman showed, in addition to the usual clinical manifestations of the disorder, severe progressive skeletal changes: osteoporotic changes with multiple fractures; osteolysis of the right radius; and destructive changes of the vertebrae, leading to compression of the cervical spinal cord and paraplegia. Laboratory findings included markedly reduced bone mineral density; significantly increased urine N-telopeptide of collagen type I, an osteoclast marker; and normal serum bone specific alkaline phosphatase, an osteoblast marker. Regular follow up of adult patients with the disorder is desirable, including skeletal radiography, estimates of bone mineral density, and biochemical markers of bone turnover. Treatment with bisphosphonates to inhibit osteoclast activity is likely to be beneficial.