Effectiveness and safety of arthroscopy combined with radial extracorporeal shockwave therapy for osteochondritis of the talus: a prospective, single-centre, randomized, double-blind study.

Aims: Arthroscopic microfracture is a conventional form of treatment for patients with osteochondritis of the talus, involving an area of < 1.5 cm2. However, some patients have persistent pain and limitation of movement in the early postoperative period. No studies have investigated the combined treatment of microfracture and shortwave treatment in these patients. The aim of this prospective single-centre, randomized, double-blind, placebo-controlled trial was to compare the outcome in patients treated with arthroscopic microfracture combined with radial extracorporeal shockwave therapy (rESWT) and arthroscopic microfracture alone, in patients with ostechondritis of the talus. Methods: Patients were randomly enrolled into two groups. At three weeks postoperatively, the rESWT group was given shockwave treatment, once every other day, for five treatments. In the control group the head of the device which delivered the treatment had no energy output. The two groups were evaluated before surgery and at six weeks and three, six and 12 months postoperatively. The primary outcome measure was the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale. Secondary outcome measures included a visual analogue scale (VAS) score for pain and the area of bone marrow oedema of the talus as identified on sagittal fat suppression sequence MRI scans. Results: A total of 40 patients were enrolled and randomly divided into the two groups, with 20 in each. There was no statistically significant difference in the baseline characteristics of the groups. No complications, such as wound infection or neurovascular injury, were found during follow-up of 12 months. The mean AOFAS scores in the rESWT group were significantly higher than those in the control group at three, six, and 12 months postoperatively (p < 0.05). The mean VAS pain scores in the rESWT group were also significantly lower than those in the control group at these times (p < 0.05). The mean area of bone marrow oedema in the rESWT group was significantly smaller at six and 12 months than in the control group at these times (p < 0.05). Conclusion: Local shockwave therapy was safe and effective in patients with osteochondiritis of the talus who were treated with a combination of arthroscopic surgery and rESWT. Preliminary results showed that, compared with arthroscopic microfracture alone, those treated with arthroscopic microfracture combined with rESWT had better relief of pain at three months postoperatively and improved weightbearing and motor function of the ankle.

Arthroscopic Ankle Arthrodesis for End-Stage Tuberculosis of the Ankle: A 2-Year Follow-Up.

Surgical treatment for end-stage ankle joint tuberculosis (TB) has rarely been reported. This study followed cases treated by arthroscopic arthrodesis for ankle joint TB to evaluate its efficacy and safety in the clinic. Patients who underwent arthroscopic ankle arthrodesis for ankle joint TB between April 11, 2010, and December 31, 2016, were followed. Their diagnoses were confirmed by bacterial culture or pathological examination. During arthroscopy, tissue samples were first obtained to further confirm the diagnosis. Then the necrotic tissue, hyperplasia of synovial tissue, and exfoliated cartilage were removed. Ankle joint arthrodesis was performed if the area of articular cartilage damage was >2 cm2. Continued nutritional support and standardized anti-TB drug treatment were given after surgery. Follow-up measurements included visual analogue scale score, American Orthopaedic Foot and Ankle Society score, erythrocyte sedimentation rate, and radiographic imaging. All 9 patients in this study, with an average age of 54 (range 37 to 68) years, were followed. The mean follow-up duration was 55.44 ± 31.15 (range 24 to 96) months. There were significant differences in the visual analogue scale scores, American Orthopaedic Foot and Ankle Society scores, and erythrocyte sedimentation rate between before treatment and 18 months postoperatively (p < .05). All patients (100%) showed union at 18 ± 4 weeks. Arthroscopic treatment for ankle joint TB has the advantages of minor trauma and low complications. It can be used to accurately obtain samples from specific areas of TB for further diagnosis. According to the degree of articular cartilage damage, the surgeon can determine whether to perform arthrodesis. Thorough debridement of necrotic tissue and residual articular cartilage on the fusion surface can improve the rate of ankle fusion.

Riboflavin Is Directly Involved in N-Dealkylation Catalyzed by Bacterial Cytochrome P450 Monooxygenases.

Like a vast number of enzymes in nature, bacterial cytochrome P450 monooxygenases require an activated form of flavin as a cofactor for catalytic activity. Riboflavin is the precursor of FAD and FMN that serves as indispensable cofactor for flavoenzymes. In contrast to previous notions, herein we describe the identification of an electron-transfer process that is directly mediated by riboflavin for N-dealkylation by bacterial P450 monooxygenases. The electron relay from NADPH to riboflavin and then via activated oxygen to heme was proposed based on a combination of X-ray crystallography, molecular modeling and molecular dynamics simulation, site-directed mutagenesis and biochemical analysis of representative bacterial P450 monooxygenases. This study provides new insights into the electron transfer mechanism in bacterial P450 enzyme catalysis and likely in yeasts, fungi, plants and mammals.

Extracorporeal Shock Wave Therapy for Pain Relief After Arthroscopic Treatment of Osteochondral Lesions of Talus.

Arthroscopic treatment is an effective technique for osteochondral lesion of talus (OLT); however, some patients still suffer pain and limitation of activities after surgery. The purpose of this study was to evaluate the efficacy of extracorporeal shock wave therapy (ESWT) after ankle arthroscopy for OLT. We reviewed the clinical history of a series of 78 patients with OLT who underwent arthroscopic microfracture. ESWT was prescribed for 15 patients who complained of ankle pain and restriction of weightbearing activities 3 months postoperatively. The parameters assessed were visual analog scale (VAS) and American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale scores (before ESWT, at 6 and 12 weeks, and at last follow-up after ESWT) and magnetic resonance imaging (MRI) before and 1 year after ESWT. Follow-up was 27.8 ± 15.2 months. VAS and AOFAS scores showed a significant improvement at 12 weeks after ESWT and a progressive trend at last follow-up. Areas of lesions in sagittal plane in MRI were distinctly reduced at last follow-up. ESWT for osteochondral lesions of talus after arthroscopy results in good clinical outcomes.

Identification of a heparosan heptasaccharide as an effective anti-inflammatory agent by partial desulfation of low molecular weight heparin.

Low molecular weight heparin (LMWH) possesses a dual function of anticoagulation and anti-inflammation. While the structures and mechanisms on its anticoagulation have been widely studied, the structural features responsible for the anti-inflammatory activity of LMWH remain to be explored. In the present study, guided by an anti-inflammation assay, a non-anticoagulant species was generated from partial desulfation of LMWH to fully retain the anti-inflammatory activity, from which five fractions were further separated and three of them were characterized by enzymatic degradation, hydrophobic labeling, C18-based HPLC and LC-MS/MS analyses. The structure-activity relationship revealed that the sulfate groups in LMWH are critical to distinguish and separate the activities of anticoagulation and anti-inflammation, leading to the identification of a synthetic heparosan-type heptasaccharide as a potent anti-inflammatory agent. The present strategy enables the simplification of complex polysaccharides to bioactive synthetic oligosaccharides for therapeutic utility.

The Use of Particulated Juvenile Allograft Cartilage for the Repair of Porcine Articular Cartilage Defects.

BACKGROUND: The repair of porcine articular cartilage defects by using particulated juvenile allograft cartilage (PJAC) has demonstrated good short-term clinical efficacy, but the repair process and mechanism have not been fully elucidated. PURPOSE: To study the efficacy of PJAC in repairing full-thickness cartilage defects and to provide an experimental basis for its clinical application. STUDY DESIGN: Controlled laboratory study. METHODS: Thirty Guizhou minipigs were randomly divided into an experimental group and control group. An 8-mm cylindrical full-thickness cartilage defect was created in the femoral trochlea of either knee in all minipigs. The experimental group received the PJAC transplantation (PJAC group; n = 15) and the control group received autologous cartilage chips (ACC group; n = 15). Five minipigs were euthanized at 1, 3, and 6 months in each group to obtain samples, which were evaluated by general view of the knee joint and histomorphometry of the chondral defect area (hematoxylin and eosin, safranin O). International Cartilage Repair Society (ICRS) II semiquantitative evaluation and collagen type II staining immunohistochemistry were also performed. RESULTS: All 30 Guizhou minipigs were followed; there was no infection or incision healing disorder after the operation. At 1 month postoperatively, more hyaline cartilage was found in the ACC group (29.4%) compared with the PJAC group (20.1%) (P < .05); there was no statistical difference between the 2 groups at 3 and 6 months after operation. The fibrocartilage content in the ACC group was significantly more than that in the PJAC group at 1 and 3 months postoperatively (27.4% vs 18.2% and 49.9% vs 41.1%, respectively; P < .05); significant differences disappeared at 6 months postoperatively. The PJAC group produced more fibrous tissue than the ACC group at 1 and 3 months postoperatively (60.1% vs 40.6% and 38.8% vs 24.4%, respectively; P < .05) but showed no statistical difference at 6 months postoperatively. Regarding the ICRS II scores, those of the ACC group were significantly better than the scores of the PJAC group in some subclasses at 3 and 6 months postoperatively. The positive rates of immunohistochemical staining in the ACC group were higher at 1 and 3 months postoperatively than those in the PJAC group (54.2% vs 37.8% and 46.4% vs 34.4%, respectively; P < .05). The difference was not statistically significant between the 2 groups at 6 months postoperatively. CONCLUSION: Both PJAC and ACC can produce a good repair effect on cartilage defects. At 1 and 3 months postoperatively, ACC resulted in better outcomes than PJAC, but there was no statistical difference in the repair effect between the 2 techniques at 6 months postoperatively. CLINICAL RELEVANCE: Based on this animal experiment, further clinical studies are needed to investigate PJAC as a possible alternative first-line treatment for cartilage defects.

Application of 3D-Printed Personalized Guide in Arthroscopic Ankle Arthrodesis.

OBJECTIVE: To accurately drill the Kirschner wire with the help of the 3D-printed personalized guide and to evaluate the feasibility of the 3D technology as well as the outcome of the surgery. METHODS: Patients' DICM data of ankle via CT examinations were introduced into the MIMICS software to design the personalized guides. Two 2mm Kirschner wires were drilled with the help of the guides; the C-arm fluoroscopy was used to confirm the position of the wires before applying the cannulated screws. The patients who underwent ankle arthrodesis were divided into two groups. The experimental group adopted the 3D-printed personalized guides, while the control group received traditional method, i.e., drilling the Kirschner wires according to the surgeon's previous experience. The times of completing drilling the Kirschner wires to correct position were compared between the two groups. Regular follow-ups were conducted to statistically analyze the differences in the ankle fusion time and AOFAS scores between the two groups. RESULTS: 3D-printed personalized guides were successfully prepared. A total of 29 patients were enrolled, 15 in the experimental group and 14 in the control group. It took 2.2 ± 0.8 minutes to drill the Kirschner wires to correct position in the experimental group and 4.5 ± 1.6 minutes in the control group (p=0.001). No obvious complications occurred in the two groups during and after surgery. Postoperative radiographs confirmed bony fusion in all cases. There were no significant differences in the fusion time (p=0.82) and AOFAS scores at 1 year postoperatively between the two groups (p=0.55). CONCLUSIONS: The application of 3D-printed personalized guide in assisting the accurate drilling of Kirschner wire in ankle arthrodesis can shorten the operation time and reduce the intraoperative radiation. This technique does not affect the surgical outcome. TRIAL REGISTRATION NUMBER: This study is registered on www.clinicaltrials.gov with NCT03626935.