Axial and frontal X-ray fluoroscopy technique of the sustentaculum tali can improve the accuracy of sustentacular screw placement.

INTRODUCTION: Calcaneal fractures, especially those involving the articular surface, should be anatomically reduced as much as possible. Fixing the fracture by placing a screw into the sustentaculum tali from the lateral side of the calcaneus is generally considered to be the key to successful surgery. However, due to the limited visibility during surgery, it is not easy to place screws into the sustentaculum tali accurately. The purpose of this study was to explore a new fluoroscopy method for the sustentaculum tali and verify the value of this method in improving screw placement accuracy. METHODS: In this study, a total of 42 human foot and ankle specimens were dissected and measured. The shape and position of the sustentaculum tali were observed, and the influence of adjacent bones on imaging findings was analysed. The axial and frontal X-ray fluoroscopy method to view the sustentaculum tali was formulated, and the appropriate projection angle through anatomical and image measurements was explored. Thirty specimens were randomly selected for screw placement, and the direction of the screw was dynamically adjusted under the new imaging method. The success rate of sustentacular screw placement was evaluated. RESULTS: The anteversion angles of the sustentaculum tali were 30.81 ± 2.21° and 30.68 ± 2.86° by anatomical and imaging measurements, respectively. There was no statistically significant difference in the anteversion angle between the two measurement methods. Harris heel views should be obtained at 30° to identify the sustentaculum tali on axial X-ray images. Frontal X-ray imaging was performed perpendicular to this projection angle. Through frontal and axial X-ray imaging, the position and shape of the sustentaculum tali can be clearly observed, and these factors are seldom affected by adjacent bones. Under the new fluoroscopy method, the screws were placed from the anterior region of the lateral wall of the calcaneus to the sustentaculum tali. A total of 60 screws were placed in the 30 specimens; of these, 54 screws were in good position, 2 screws penetrated the cortical bone, and 4 screws did not enter the sustentaculum tali. The success rate of sustentacular screw placement was 90% (54/60). CONCLUSIONS: Axial and frontal X-ray images of the sustentaculum tali can clearly show the shape of the structure, which improves sustentacular screw placement accuracy.

Pseudogene MSTO2P enhances hypoxia-induced osteosarcoma malignancy by upregulating PD-L1.

Hypoxia has been shown to be related to osteosarcoma development and progression. Pseudogene MSTO2P was reported to be dysregulated in hepatocellular carcinoma and lung cancer. However, the mechanism by which MSTO2P-modulated osteosarcoma remains unclear. MSTO2P and PD-L1 expression levels were examined by RT-qPCR and westernblot. Tumor cell invasion was determined by tranwell assay. EMT process was probed by determining E-cadherin and Vimentin levels. Soft agar assay was used to examine anchorage-independent growth of osteosarcoma cells. In vivo tumor growth was measured by xenografting tumor experiment. Hypoxia treatment promoted cell growth, invasion and EMT of osteosarcoma cells. MSTO2P knockdown led to attenuated cell growth, invasion and EMT of osteosarcoma cells under hypoxia condition. More interestingly, our data revealed that MSTO2P was positively associated with tumor growth in immunodeficient mice and human clinical tissues. PD-L1 was shown to act as a key effector for MSTO2P-regulated osteosarcoma progression under hypoxia condition. In conclusion, we unravel a novel mechanism for explaining MSTO2P-involved osteosarcoma progression under hypoxia condition, which will facilitate development of potential diagnostic and therapeutical strategies for osteosarcoma.

Three-dimensional printing technique aids screw insertion into the sustentaculum tali of the internal fixation of intra-articular calcaneal fractures.

INTRODUCTION: Treating complex calcaneus fractures remains challenging. This study evaluated the influence of 3D printing and simulation on precision screw insertion into the calcaneus sustentaculum tali (ST). HYPOTHESIS: 3D printing and simulation improve the treatment for calcaneal fracture. PATIENTS AND METHODS: This retrospective cohort study included 85 patients admitted with 93 Sanders type II-IV intra-articular fractures from January 2015 to June 2020. Multi-slice computed tomography (MSCT) images were used in the conventional group, and MSCT data were used to construct a 3D model of the calcaneus to simulate screw insertion and verify parameter accuracy in the 3D group. RESULTS: The designed parameters (upward and backward oblique angles and screw-path length) were similar to the actual values in the 3D group (p=0.428,0.287,0.585) but not in the conventional group (p=0.01,0.002,0.023). The Maryland foot functional score, accuracy rate, and average screw number were higher and operative time was shorter in the 3D group (p=0.005,0.007,0.000,0.000). DISCUSSION: Preoperative simulation using the 3D printing model helped guide the screws into the ST more accurately, lending better-quality treatment for Sanders type II-IV calcaneal fractures. LEVEL OF PROOF: III; Retrospective case-control study.

Micturition reflex arc reconstruction including sensory and motor nerves after spinal cord injury: urodynamic and electrophysiological responses.

OBJECTIVE: To evaluate artificial reflex arcs for micturition using urodynamics and electrophysiological recordings. DESIGN: Sixteen beagles were equally and randomly divided into two groups. METHODS: In group A, anastomosis of the proximal end of the left L7 ventral root (VR) and distal end of the left S2 VR was performed, as well as anastomosis of the L7 dorsal root (DR) and S2 DR to reconstruct the sensory and the motor function of the bladder. In group B the proximal end of the left L7 VR and the distal end of the left S2 VR were anastomosed, while the left L7 DR was kept intact to reconstruct the motor function of the bladder. Outcome measures included electrophysiological testing and the urodynamic measures. In addition, we also monitored urinary infection rates. RESULTS: Stimulation to the left S2 DR in groups A and B both elevated the bladder pressure before and after the spinal lower motor neuron lesion. Single stimulation of the two groups both elicited evoked action potentials. Urinary infections occurred in group A (three occurrences) and in group B (eight occurrences) during the 3 months after the spinal lower motor neuron lesion. CONCLUSION: Data showed that both reconstructive methods could induce bladder micturition and evoked action potentials. However, in group A the micturition response was better and the urinary infection rates were lower after the spinal lower motor neuron lesion. Thus, the artificial physiological reflex arc reconstruction method used in group A, with sensory input above the lesion, might provide a better alternative in clinical practice.

Effect of Intra-articular Ketorolac Versus Corticosteroid Injection for Knee Osteoarthritis: A Retrospective Comparative Study.

BACKGROUND: Intra-articular corticosteroid injections have been widely used and are considered a mainstay in the nonoperative treatment of symptomatic knee osteoarthritis (OA). However, their increased use can have negative implications, including chondral toxicity and a high risk of infections. As a result, nonsteroidal anti-inflammatory drugs have been considered as an alternative. PURPOSE: To determine the pain relief and safety of ketorolac versus a corticosteroid to supplement an intra-articular sodium hyaluronate injection for the treatment of symptomatic knee OA. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 84 patients with unilateral symptomatic knee OA receiving 5 weekly injections were enrolled in this retrospective study. Group A (n = 42) received 3 weekly intra-articular corticosteroid injections (0.5% lidocaine, 25 mg of triamcinolone acetonide, and 25 mg of sodium hyaluronate, followed by 2 weekly injections of 0.5% lidocaine and 25 mg of sodium hyaluronate), while group B (n = 42) received 5 weekly ketorolac injections (0.5% lidocaine, 10 mg of ketorolac, and 25 mg of sodium hyaluronate). The following parameters were used to evaluate pain relief and safety: visual analog scale (VAS) for pain, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and side effects before the injection and at 1, 2, and 5 weeks after treatment commencement as well as 3 months after the last injection. RESULTS: Patients from both groups had a significant improvement in VAS and WOMAC scores from the first injection to final follow-up at 3 months. In the first week, the VAS score was lower in group A (P = .041), but no significant between-group differences were found for either the VAS or the WOMAC score at the other time points. Of the 42 patients in group A, 34 (81.0%) and 25 (59.5%) achieved successful outcomes at 5 weeks after treatment commencement and 3 months after the last injection, respectively. In group B, 32 (76.2%) and 24 (57.1%) patients achieved successful outcomes at 5 weeks after treatment commencement and 3 months after the last injection, respectively. At final follow-up, no significant difference was found in the successful treatment rate between the groups (P = .825). CONCLUSION: The current study demonstrated that intra-articular ketorolac and corticosteroid injections produce the same pain relief and functional improvement.

[Experimental study on establishment of physiological micturition reflex arc for atonic bladder after spinal cord injury].

OBJECTIVE: To investigate the feasibility of establishment of physiological micturition reflex arc by simultaneously reconstructing the sensory and the motorial nerve of atonic bladder after spinal cord injury. METHODS: Eight 1-year-old Beegle male canine were selected, weighing 7-12 kg. The left side was the experimental side, while the right side was the control side. Epidural microanastomosis of vertebral canal of the left L7 ventral root to S2 ventral root and L7 dorsal root to S2 dorsal root was performed to reconstruct the sensory and the motorial function of atomic bladder. The right side was used as a control without treatment. The new motor-to-motor, and sensory-to-sensory physiological bladder reflex pathway were established after 12 months of axonal regeneration. Then S1-4 segmental spinal cord was destroyed for preparation of complete paraplegia. The electrophysiological examination and the bladder pressure were detected before and after paraplegia. The canine micturition was observed for 3 months after paraplegia. Neurohistological observation was performed after canine sacrifice. RESULTS: Of 8 canine, 7 canine survived. After paraplegia, canines displayed urinary incontinence and frequent micturition at first, nocturnal continence was achieved gradually without frequent micturition after 1 month. Urinary infection at different degrees occurred in 3 canines and was controlled after Norfloxacin was administered orally. The bladder pressure increased to (1.00 +/- 0.13) kPa, (0.90 +/- 0.12) kPa after trains of stimulation (300 mV, 0.3 ms, 20 Hz, 5 seconds) of S2 dorsal root at the experimental side before and after paraplegia respectively, showing no significant difference (P > 0.05). It increased to (1.90 +/- 0.10) kPa after the same train of stimulation of S2 dorsal root at control side. There was significant difference between the experimental side and the control side (P < 0.01). Single stimulation (300 mV, 0.3 ms) of the S2 dorsal root at the experimental side resulted in evoked potentials recorded from the left S2 ventral root before and after paraplegia. Before and after paraplegia, the amplitudes of the evoked potentials were (0.68 +/- 0.11) mV and (0.60 +/- 0.08) mV respectively, showing no significant difference (P > 0.05). It was (1.21 +/- 0.13) mV while stimulating at the control side. There was significant difference between the experimental side and the control side (P < 0.01). Neurofibra of L7 dorsal and ventral root grew into S2 dorsal and ventral root on tissue slice under light microscope. CONCLUSION: Reconstruction of the bladder physiological micturition reflex arc is feasible by anastomosis of sacral dorsal and ventral root below injured spinal plane with the suprasacral survival dorsal and ventral root above the plane respectively for restoration of atonic bladder after spinal cord injury.