Establishment of a Finite Element Model and Biomechanical Analysis of Different Fixation Methods for Total Talar Prosthesis Replacement

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Bio-tribological behavior of articular cartilage based on biological morphology

Artificial hemiarthroplasty is one of the effective methods for the treatment of hip joint diseases, but the wear failure of the interface between the hemi hip joint material and articular cartilage restricts the life of the prosthesis. Therefore, it is important to explore the damage mechanism between the interfaces to prolong the life of the prosthesis and improve the life quality of the prosthesis replacement. In this paper, the creep and bio-tribological properties of cartilage against PEEK, CoCrMo alloy, and ceramic were studied, and the tribological differences between “hard–soft” and “soft–soft” contact were analyzed based on biomorphology. The results showed that with the increase of time in vitro, the thickness of the cartilage membrane decreased, the surface damage was aggravated, and the anti-creep ability of cartilage was weakened. Second, the creep resistance of the soft–soft contact pair was better than that of the hard–soft contact pair. Also, the greater the load and the longer the wear time, the more serious the cartilage damage. Among the three friction pairs, the cartilage in PEEK/articular cartilage was the least damaged, followed by CoCrMo alloy/articular cartilage, and the most damage was found in ceramic/articular, indicating that the soft–soft friction pair inflicted the least damage to the cartilage.

The First Reported Case of Hemoptysis After Silicone Gel Breast Implants

Background: Hemoptysis after silicone breast prosthesis surgery has not been reported so far, and the mechanism is unclear. Case presentation: A 25-year-old young woman presented hemoptysis after silicone breast prosthesis replacement surgery. CTA revealed diffuse interstitial, alveolar, and terminal bronchial exudate changes in absent of pulmonary embolism. Noninvasive ventilator assisted breathing, combined with atomized inhalation of budesonide 2ml every 8h and intravenous infusion of hydrocortisone 100mg every 12h. Chest CT improved significantly 3 days later, and discharged 10 days later. Conclusions: Diffuse alveolar hemorrhage might be the cause of hemoptysis after silicone breast augmentation, and glucocorticoid treatment is very effective. However, if pulmonary imaging suggested diffuse pulmonary hemorrhage, BAL and lung biopsy should be performed to confirm the clinical diagnosis before treatment.

Comparative observation of two types of limb salvage surgery on limb function and quality of life in patients with knee joint osteosarcoma

Background We compared the differences of Joint-preservation Limb Salvage (JPLS) and Joint-prosthesis Replacement Surgery (JPRS) on limb function and quality of life in patients with osteosarcoma in the knee. Methods This retrospective study evaluated the postoperative outcomes of patients treated with JPLS and JPRS for osteosarcoma around the knee between November 2000 and January 2019. All patients were followed up at 1 year postoperatively. Patients' lower extremity function, knee function, and quality of life were evaluated during follow-up using the MSTS score, IKDC score, and SF-36 score. Results The patients were divided into two groups: the joint-preservation group (16) and the prosthetic-replacement group (19). All 35 patients received a successful operation, and all incisions healed in one stage after surgery. At 12 months after the operation, the median MTST score in the joint-preservation group was 27(range 24 to30), higher than 24(range 13 to 30) in the prosthetic-replacement group (P < 0.05, Table 2). The median IKDC score in the joint-preservation group was 82.5(range 53 to 95), higher than the 60(range 41 to 80) in the prosthetic- replacement group (P < 0.05, Table 2). The SF-36 scores of physiological and social functions were higher in the joint-preserving group than those in the prosthetic-replacement group (P < 0.05), and there were no significant differences between the groups in the other indexes (P > 0.05). Comparing the distribution of each item in the MSTS and IKDC scoring criteria between the joint-preservation and the prosthetic-replacement group revealed that the limb function, pain, satisfaction, support assistance, and the walking and gait of the joint-preservation group were superior to those of the prosthetic-replacement group (P < 0.05). There was no significant difference in knee flexion between the two groups (P > 0.05). However, the joint-preservation group performed superior to the prosthesis-replacement group in terms of pain, swelling, twisting, softening of the leg, movement downstairs, sitting up from a chair, kneeling, squatting, running straight, jumping up with the injured leg and landing, and quickly stopping or starting (P < 0.05). Conclusion Compared with joint-prosthesis replacement surgery, joint-preservation limb salvage performed better joint function and quality of life. The findings provide a signal of superiority for JPLS to JPRS but further investigation is warranted in multicentre trials.

Rhizarthrosis Bilateral – Trapeziectomy Versus Arthroplasty with Dual Mobility Prosthesis: Case Report

Background: The trapeziometacarpal joint is the second joint affected by osteoarthritis in the hand. The symptoms and clinical presentation are characterized by pain, limited range of motion, muscle weakness with loss of strength, bone deformities and disability. The symptomatology often is not related to the radiographic grade of osteoarthrosis. Therefore, in addition to the radiographic stage of the disease, the treatment is influenced by multiple variables such as age, functional requirement, symptoms and stability of the joint. Objective: There are several options of surgical treatments. Although trapeziectomy and its technical variation is the gold standard for treatment, prosthesis replacement can be used with good results. This case report discusses the case of a 70-year-old male who presents bilateral trapeziometacarpal osteoarthrosis treated with two different techniques with different timelines. Methods: The patient underwent a trapeziectomy on the right hand and arthroplasty with implant on the left. In both TMC the stage of the disease was grade III according to the Eaton Litter classification and the results were evaluated according to clinical and radiographic criteria. The NPRS pain scale and the Quick Dash functional scale were used in subsequent checks. The mean follow-up was 12 months. Conclusion: There were no significantly different results with respect to pain, activities of daily living, mobility or strength. No complications were observed. The patient is satisfied with the treatment having found a better and earlier resumption of daily activity of the left hand treated with prosthesis replacement.

Gastric perforation caused by secondary systemic amyloidosis

An 82-year-old man, suffering abscess secondary to femoral prosthesis replacement, complained of intractable watery diarrhea and melena. Autopsy disclosed 12 mm-sized perforation at the gastric prepylorus and purulent peritonitis. Amyloid A was deposited in systemic organs and tissues, including the site of gastric perforation. IgM was co-deposited in the glomeruli.

Comparative Observation of Two Types of Limb Salvage Surgery on Limb Function and Quality of Life in Patients With Knee Joint Osteosarcoma

BackgroundWe compared the effects of two surgical procedures on limb function and quality of life in patients with osteosarcoma in the knee.MethodsThis retrospective study evaluated the postoperative outcomes of patients treated with JPLS and JPRS for osteosarcoma around the knee between November 2000 and December 2019. All patients were followed up for at least one year. Patients' lower extremity function, knee function, and quality of life were evaluated during follow-up using the MSTS score, IKDC score, and SF-36 score.ResultsAll 38 patients received a successful operation, and all incisions healed in one stage after surgery. At 12 months after the operation, the MSTS score in the prosthetic-replacement group (22.79±5.22) was lower than that in the joint-preservation group (27.05±1.62)(P=0.002). The IKDC score was lower in the prosthetic-replacement group (59.89±11.22) than in the joint-preservation group (76.84±9.42)( P <0.001). After 12 months, the SF-36 scores of physiological and social function in the joint-preserving group were higher than those in the prosthetic-replacement group (P <0.05), and there were no significant differences among the other indexes (P >0.05). Comparing the distribution of each item in the MSTS and IKDC scoring criteria between the joint-preservation and the prosthetic-replacement group revealed that the limb function, pain, satisfaction, support assistance, and the walking and gait of the joint preservation group were superior to those of the prosthetic-replacement group (P < 0.05). There was no significant difference in knee flexion between the two groups (P > 0.05). However, the joint preservation group was superior to the prosthesis replacement group in terms of pain, swelling, twisting, softening of the leg, movement downstairs, sitting up from a chair, kneeling, squatting, running straight forward, jumping up with the injured leg and landing, and quickly stopping or starting (P < 0.05).ConclusionCompared with joint-prosthesis replacement surgery, joint-preservation limb salvage leads to better joint function and quality of life. To improve the limb function and quality of life of patients with long-term survival osteosarcoma, joint-preservation limb salvage should be carried out according to the principles of Operation Indication, neoadjuvant and effective chemotherapy.

Mid-Carpal Joint Sparing Procedure for Idiopathic Avascular Necrosis of Capitate

Background Avascular necrosis of the capitate (AVNC) is an uncommon pathology of the wrist. Several procedures have been described for the treatment of AVNC. The type of treatment varies depending upon the stages. In early stages, revascularization procedures are performed. If secondary osteoarthritis develops, then the treatment options include intercarpal fusion, four corner fusion, prosthesis replacement of the capitate, tendon interposition, and wrist arthrodesis. No long-term study is available for choosing an appropriate method of the treatment for AVNC. Case Description Herein, we report a case of AVNC that was managed by hemi-resection of the capitate with capito-hamate fusion and tendon interposition. One year after surgery, patient was asymptomatic and radiographs revealed fusion of capito-hamate joint and maintenance of the mid-carpal joint space. There was no evidence of carpal collapse. Literature Review All the literature about mid-carpal joint sparing (MCJS) procedures has been reviewed in this report. This is a goal behind writing of this case report as there have been very few publications about these procedures. Clinical Relevance This case illustrates the successful treatment of AVNC by MCJS procedure. The intercarpal fusion and the four corner fusion are one time procedures, and these can be used if the MCJS procedure fails or sometimes, as primary procedure, if the patient gives consent for the same. It appears prudent to save arthrodesis procedures for the future.

Timing of surgery for benign periacetabular tumor: virtual finite element analysis and clinical verification on 39 cases

BackgroundThe treatment of periacetabular tumor has always been met with great challenges, including the lack of a standard for the timing of surgery. The purposes of this study were to predict the risk for fracture by finite element analysis of benign periacetabular tumor; to guide the timing of operation; and to verify the practical application of this standard through clinical cases. MethodsBone defects in different areas of the acetabulum were constructed, and the fracture risk was predicted by finite element analysis. According to the results of finite element analysis and Enneking classification, the patients with benign periacetabular tumor were divided into the low fracture risk noninvasive lesion, low fracture risk invasive lesion, and high fracture risk groups. The grouping was used to guide the timing of operation. ResultsThis study included 39 patients who were followed-up for at least two years to verify the effectiveness of this program. The 12 patients in the low risk noninvasive lesion group that did not undergo operation showed no obvious pathological changes and no pathological fracture; there was no significant difference in the MSTS-93 score between the first and last visits (P > 0.05). The 7 patients in the low risk invasive lesion group were treated with adjuvant therapy before the operation; the MSTS-93 score was significantly lower on the first visit than on the last visit (P < 0.05). The 20 cases that had high risk for fracture underwent surgery after the diagnosis; of these, 13 patients achieved osseointegration of the graft bone and 7 patients had no prosthesis loosening, detachment, displacement or rupture after prosthesis replacement. The MSTS-93 score significantly improved from a preoperative value of 19.61 ± 7.32 to a final follow-up value of 26.28 ± 15.59 (P < 0.01). ConclusionsOur study confirmed that for benign periacetabular tumor, finite element analysis, combined with the nature of the tumor, can predict the risk for acetabular fracture and guide the appropriate timing and method of operation, thereby, enabling a safe therapeutic effect.