Objective To probe into the effectiveness of vertical compression of locking plate combined with hollow screws in the treatment of Sanders type Ⅱ and Ⅲ calcaneal fractures. MethodsThe clinical data of 128 patients with Sanders type Ⅱ and Ⅲ calcaneal fractures who were admitted between March 2019 and April 2022 and met the selection criteria were retrospectively analyzed. Among them, 65 patients were treated with locking plate combined with hollow screw vertical compression (study group), and 63 patients were treated with simple locking plate (control group). There was no significant difference in baseline data between the two groups (P>0.05), such as gender, age, fracture side and Sanders classification, cause of injury, time from injury to operation. The operation time, intraoperative blood loss, hospital stay, and fracture healing time were recorded and compared between the two groups. Before operation and at 12 months after operation, the American Orthopaedic Foot and Ankle Association (AOFAS) score (including total score, pain score, functional score, and alignment score) was used to evaluate the recovery of foot function, and imaging indicators such as calcaneal width, calcaneal height, calcaneal length, Böhler angle, and Gissane angle were measured on X-ray films. ResultsAll patients were followed up 12 months after operation. There was no significant difference in operation time, intraoperative blood loss, hospital stay, and fracture healing time between the two groups (P>0.05). Poor wound healing occurred in 1 case in the study group and 2 cases in the control group. At 12 months after operation, there was no significant difference between the two groups in the pre- and post-operative difference of calcaneal length, calcaneal height, Gissane angle, and Böhler angle (P>0.05). However, the pre- and post-operative difference in calcaneal width in the study group was significantly higher than that in the control group (P<0.05). The pre- and post-operative difference of AOFAS total score in the study group was significantly higher than that in the control group (P<0.05), and further analysis showed that the pre- and post-operative difference of pain and function scores in the study group were significantly higher than those in the control group (P<0.05), while there was no significant difference in the pre- and post-operative difference of force score between the two groups (P>0.05). ConclusionCompared with simple locking plate treatment, the treatment of Sanders type Ⅱ and Ⅲ calcaneal fractures with vertical compression of locking plate combined with hollow screws can more effectively improve the width of the subtalar calcaneal articular surface, avoid peroneal longus and brevis impingement, reduce pain, and increase the range of motion of the subtalar joint, and the effectiveness is better.
ObjectiveTo compare the effectiveness of subtalar arthroereisis (STA) combined with modified Kidner procedure versus STA alone in the treatment of flexible flatfoot combined with painful accessory navicular bone in children. MethodsThe clinical data of 33 children with flexible flatfoot combined with painful accessory navicular bone who were admitted between August 2018 and August 2021 and met the selection criteria were retrospectively analyzed. They were divided into a combination group (17 cases, treated by STA combined with modified Kidner procedure) and a control group (16 cases, treated by STA alone) according to the surgical methods. There was no significant difference in baseline data between the two groups (P>0.05), such as gender, age, affected side of the foot, disease duration, and preoperative visual analogue scale (VAS) score, American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, talus-first metatarsal angle (T1MT), talus-second metatarsal angle (T2MT), talonavicular coverage angle (TCA), talus first plantar angle (Meary angle), calcaneal inclination angle (Pitch angle), and heel valgus angle (HV). The operation time, incision length, intraoperative blood loss, number of intraoperative fluoroscopies, and perioperative complications were recorded in both groups. The anteroposterior, lateral, and calcaneal axial X-ray films for the affected feet were taken regularly, and T1MT, T2MT, TCA, Meary angle, Pitch angle, and HV were measured. The VAS score, AOFAS ankle-hindfoot score were used to evaluate pain and functional recovery before and after operation. ResultsSurgeries in both groups were successfully performed without surgical complication such as vascular, nerve, or tendon injuries. Less operation time, shorter incision length, less intraoperative blood loss, and fewer intraoperative fluoroscopies were found in the control group than in the combination group (P<0.05). One case in the combination group had partial necrosis of the skin at the edge of the incision, which healed after the dressing change and infrared light therapy, and the rest of the incisions healed by first intention. All children were followed up 12-36 months, with a mean of 19.6 months. At last follow-up, VAS score and AOFAS ankle-hindfoot score significantly improved in both groups when compared with preoperative ones (P<0.05), and the differences of these scores between before and after operation improved more significantly in the combination group than in the control group (P<0.05). Imaging results showed that the T1MT, T2MT, TCA, Meary angle, and HV significantly improved in both groups at last follow-up when compared with preoperative ones (P<0.05), and the Pitch angle had no significant difference when compared with preoperative one (P>0.05). But there was no significant difference in the difference of these indicators between before and after operation between the two groups (P>0.05).ConclusionBoth procedures are effective in the treatment of flexible flatfoot children with painful accessory navicular bone. STA has the advantage of minimally invasive, while STA combined with modified Kidner procedure has better effectiveness.
Objective To measure the concentration of bone morphogenetic protein 2 (BMP-2) in demineralized bone matrix (DBM) prepared from different long bones and to evaluate the osteoinductivity of different DBM on MC3T3-E1 cells. Methods Different bones from the same cadaver donor were used as the initial materials for making DBM, which were divided into ulna group (uDBM), humerus group (hDBM), tibia group (tDBM), and femur group (fDBM) according to the origins, and boiled DBM (cDBM) was taken as the control group. The proteins of DBM were extracted by guanidine hydrochloride, and the concentrations of BMP-2 were determined by ELISA assay. Then the DBM were co-cultured with MC3T3-E1 cells, the proliferation of MC3T3-E1 cells was observed by cell counting kit 8 (CCK-8) assay. The osteogenic differentiation ability of MC3T3-E1 cells was qualitatively observed by alizarin red, alkaline phosphatase (ALP), and Van Gieson staining, and the osteogenic differentiation ability of MC3T3-E1 cells was quantitatively analyzed by ALP content. Linear regression was used to analyze the effect of BMP-2 concentration in DBM on ALP synthesis. ResultsThere were significant differences in the concentration of BMP-2 among the DBM groups (P<0.05). The concentrations of BMP-2 in the lower limb long bone were higher than those in the upper limb long bone, and the concentration of BMP-2 in the fDBM group was about 35.5 times that in the uDBM group. CCK-8 assay showed that the cells in each group continued to proliferate within 5 days of co-culture, and the absorbance (A) values at different time points were in the order of cDBM group<uDBM group<hDBM group<tDBM group<fDBM group. After co-culture for 14 days, the expressions of ALP, calcified nodules, and collagen fibers in each group were consistent with the distribution of BMP-2 concentration in DBM. The order of ALP content from low to high was cDBM group<uDBM group<hDBM group<tDBM group<fDBM group, and the differences between the groups were significant (P<0.05). Linear regression analysis showed that \begin{document}$\hat y $\end{document}=0.361+0.017x, the effect of BMP-2 concentration in DBM on cellular ALP content was significant (t=3.552, P=0.005); for every 1 ng/g increase in BMP-2 concentration, ALP content would increase by 0.017 [95%CI (0.006, 0.027)] U/100 mL. Conclusion The concentration of natural BMP-2 in different long bones varies greatly, and the lower limb long bone is higher than the upper limb long bone. The harvested location of bone material was an important factor affecting the osteoinductivity of DBM.