Duration of electrochemical deposition affects the morphology of hydroxyapatite coatings on 3D-printed titanium scaffold as well as the functions of adhered MC3T3-E1 cells.

BACKGROUND: The use of 3D-printed scaffolds in repairing bone defects remains unexplored. We aimed to determine whether the duration of electrochemical deposition (ECD) affects the properties of hydroxyapatite (HA) coatings on 3D-printed titanium (TI) scaffolds as well as the corresponding phenotype of MC3T3-E1 cells seeded on these surfaces. METHODS: Five groups of HA-coated TI scaffolds were produced using different durations of ECD (0, 5, 10, 20, and 30 min) and examined under scanning electron microscopy (SEM). MC3T3-E1 cell adhesion to the HA-coated scaffolds and subsequent proliferation and viability were assessed using SEM, DAPI staining, EdU staining, and Alamar Blue assay, respectively. MC3T3-E1 cell expression of osteogenic genes was analyzed by fluorescence RT-PCR. RESULTS: On SEM, longer ECD durations resulted in more compact HA crystals of differing morphology coated onto the TI scaffolds. MC3T3-E1 cell adhesion differed among the five groups (p < 0.05), with the largest number of cells adhered to the scaffolds prepared with 30 min of ECD, followed by the group prepared with 20 min of ECD. However, the ECD duration of 20 min was associated with the highest cell viability and proliferation rate (both p < 0.05) as well as the highest mRNA expression levels of alkaline phosphatase, collagen I, osteocalcin and runt-related transcription factor 2 among the five groups (p < 0.05). CONCLUSIONS: In the fabrication of HA-coated 3D printed TI scaffolds, an ECD duration of 20 min resulted in scaffolds that best promoted MC3T3-E1 cell viability, proliferation and osteogenic gene expression.

Preoperative high-intensity strength training combined with balance training can improve early outcomes after total knee arthroplasty.

BACKGROUND: To investigate the effect of preoperative high-intensity strength training combined with balance training on the knee function of end-stage knee osteoarthritis (KOA) patients after total knee arthroplasty (TKA). METHODS: A prospective study was conducted on end-stage KOA patients awaiting TKA. The patients were divided into an experimental group and a control group according to whether they received a preoperative training intervention. The differences in knee flexor-extensor strength, knee range of motion (ROM), timed up and go (TUG) test result, stair ascend/descend test result, Knee Society score (KSS) and Berg balance scale (BBS) score were assessed in both groups at baseline (T1), before operation (T2), 3 months after operation (T3), and 1 year after operation (T4). RESULTS: After high-intensity strength training and balance training, the knee flexor-extensor strength, TUG test result, stair ascend/descend test result, and KSS were all significantly improved at T2 in the experimental group over the control group. At T3, the knee ROM, knee flexor-extensor strength, TUG test result, BBS score, and KSS clinical and functional scores were all significantly superior in the experimental group. The experimental group enjoyed a superiority in KSS clinical and functional scores until T4. Group × time and between-group interactions were found in all assessment indicators in both groups (p < 0.01). CONCLUSION: Preoperative high-intensity strength training combined with balance training can enhance the knee flexor-extensor strength and balance of patients with end-stage KOA in the short term and help improve early outcomes after KOA. Trial registration ChiCTR2000032857, 2020-05-13.

[Study on the correlation between the arc height of cervical endplate and osteophyte in posterior margin of intervertebral space].

OBJECTIVE: To study the correlation and clinical value of the arc height of upper and lower endplates, the height of intervertebral space and osteophyte of posterior edge of intervertebral space in patients with cervical spondylosis. METHODS: A total of 108 patients with cervical spondylosis who underwent cervical spondylosis surgery from September 2017 to September 2018 were included in the study. Including 48 males with an average age of 52 years (30 to 72) and 60 females with an average age of 54 years (37 to 79). Among them, C2,3 of 6 cases, C3,4 of 15 cases, C4,5 of 32 cases, C5,6 of 42 cases, C6,7 of 13 cases. X-ray films of cervical spine were taken before and after operation. The images were accessed by PACS (Picture Archiving and Communication Systems) system. The lower and upper endplate arc heights (L1, L2), intervertebral space height (L3), and posterior osteophyte width (L4) were measured. Spearman was used to analyze the correlation between them. RESULTS: L1 was negatively correlated with L4 (r=-0.34, P<0.05), L3 was negatively correlated with L4 (r=-0.36, P<0.05). L1 was positively correlated with L3 (r=0.38, P<0.05), L2 was positively correlated with L3 (r=0.48, P<0.05). There was no significant difference between L 1 and L2 (P>0.05), L2 and L4 (P>0.05). CONCLUSION: The arc height of the lower endplate is negatively correlated with the width of osteophyte in the posterior margin of the intervertebral space. The cervical degeneration degree can be determined by measuring the arc height of the lower endplate, which has guiding significance for the early prevention and treatment of cervical spondylosis.