ObjectiveTo compare the biomechanical characteristics of self-made nickel-titanium shape memory alloy stepped plate with calcaneal plate and cannulated compression screws in fixing calcaneal osteotomy.MethodsCalcaneal osteotomy was operated on 6 fresh-frozen lower limbs collected from donors. Then three kinds of fixation materials were applied in random, including the self-made nickel-titanium shape memory alloy stepped plate (group A), calcaneal plate (group B), and cannulated compression screws (group C). Immediately after fixation, axial loading of 20-600 N and 20 N/s in speed was introduced to record the biomechanical data including maximum displacement, elastic displacement, and maximum load. Then fatigue test was performed (5 Hz in frequency and repeat 3 000 times) and the same axial loading was introduced to collect the biomechanical data. Finally, the axial compression stiffness before and after fatigue test were calculated.ResultsThere was no significant difference in the axial compression stiffness between pre- and post-fatigue test in each group (P>0.05). However, the axial compression stiffness was significant higher in group A than that in groups B and C both before and after fatigue test (P<0.05). No significant difference was found between group B and group C (P>0.05).ConclusionSelf-made nickel-titanium shape memory alloy stepped plate is better than calcaneal plate and cannulated compression screws in axial load stiffness after being used to fix calcaneal osteotomy.
ObjectiveTo explore the effectiveness and advantage of three-dimensional (3D) printed navigation templates assisted Ludloff osteotomy in treatment of moderate and severe hallux valgus.MethodsBetween April 2013 and February 2015, 28 patients (28 feet) with moderate and severe hallux valgus who underwent Ludloff osteotomy were randomly divided into 2 groups (n=14). In group A, the patients were treated with Ludloff osteotomy assissted with a 3D printed navigation template. In group B, the patients were treated with traditional Ludloff osteotomy. There was no significant difference in gender, age, affected side, and clinical classification between 2 groups (P>0.05). The operation time and intraoperative blood loss were recorded. The ankle function of the foot at preoperation, immediate after operation, and last follow-up were assessed by the American Orthopedic Foot and Ankle Society (AOFAS) score. Besides, the X-ray film were taken to assess the hallux valgus angle (HVA), intermetatarsal angle (IMA), and the first metatarsal length shortening.ResultsAll patients were followed up 18-40 months (mean, 26.4 months). The operation time and intraoperative blood loss in group A were significantly less than those in group B (P<0.05). The HVA, IMA, and AOFAS scores in groups A and B at immediate after operaton and last follow-up were sinificantly improved when compared with preoperative values (P<0.05); but no significant difference was found between at immediate after operation and at last follow-up (P>0.05). No significant difference was found in HVA and IMA between group A and group B at difference time points (P>0.05). There were significant differences in AOFAS score and the first metatarsal length shortening at immediate after operation and at last follow-up between 2 groups (P<0.05). Except 1 case of metastatic metatarsalgia in group B, there was no other operative complications in both groups.Conclusion3D printed navigation template assisted Ludloff osteotomy can provide accurate preoperative planning and intraoperative osteotomy. It is an ideal method for moderate and severe hallux valgus.
ObjectiveTo investigate the diagnosis and treatment of thumb polydactyly with symphalangism in children.MethodsSeven cases of thumb polydactyly with symphalangism were treated between January 2013 and May 2017. There were 5 males and 2 females, aged from 10 months to 11 years, with an average age of 3.1 years. The thumb-polydactyly was diagnosed with MRI and it was seen that the base of radial multi-finger and the proximal phalangeal joint were connected by cartilage. All patients were treated with resection, lateral collateral ligament reconstruction, bone osteotomy and internal fixation.ResultsThe operation was successfully completed, and there was no early complications such as infection and flap necrosis. All patients were followed up 6-23 months (mean, 14.1 months). At last follow-up, there was no deformity finger, scar contracture, and other complications. The extension of the interphalangeal joint was no limited, and the flexion range of the interphalangeal joint was 20-75° (mean, 56.7°). The appearance and function of the thumb was rated as excellent in 3 cases and good in 4 cases by Japanese Society for Surgery of the Hand (JSSH) scoring, with the excellent and good rate of 100%.ConclusionThe thumb polydactyly with symphalangism in children can be combined with clinical manifestations, X-ray film, and MRI examination to diagnose, and can obtain satisfactory results through the reconstruction of lateral collateral ligament, bone osteotomy, and internal fixation.
ObjectiveTo explore the effectiveness of anterograde fascial flap of digital artery in reconstruction of Wassel Ⅳ-D thumb duplication.MethodsTwelve cases of Wassel Ⅳ-D thumb duplication were treated with anterograde fascial flap of digital artery between June 2014 and March 2017. There were 7 boys and 5 girls with an age of 9-32 months (mean, 13.3 months). Eight cases were on the left side and 4 cases on the right side. The main bunion bed width was 70%-85% of the healthy side (mean, 75.3%). The degree of fullness was 50%-75% of the healthy side (mean, 62.4%). The anterograde fascial flap with one proper digital artery was used to fill the nail fold on the radial side of the finger and increase the circumference of the finger. At last follow-up, the ratio of circumference of deformed finger to contralateral finger was measured at the base of nail. The appearance and function of all reconstructed thumbs were evaluated with Japanese Society for Surgery of the Hand (JSSH) scoring.ResultsAll the operations were successfully completed without early complications such as infection and skin necrosis. All children were followed up 7-27 months (mean, 14.3 months). At last follow-up, there was no recurrence of deformity in the digital body and no obvious change of scar contracture in the surgical wound. Pulp and nail fold symmetry improved in all cases. The ratio of circumference of deformed finger to contralateral finger was 93%-96% (mean, 94.7%). The JSSH score was 15-20 (mean, 17.9); the results were excellent in 8 cases, good in 2 cases, and fair in 2 cases.ConclusionThe anterograde fascial flap of digital artery is a safe and effective approach to restore symmetry for esthetic improvement in treatment of Wassel Ⅳ-D thumb duplication.
Objective To explore the application of individualized transiliac crest nail-grafting guide plate prepared by computer-aided design and three-dimensional (3D) printing technology in deep pelvic external fixator implantation. Methods Five patients with pelvic fractures were collected between May 2017 and February 2018. There were 4 females and 1 male with an average age of 52 years (range, 29-68 years). Pelvic fractures were classified as type B in 3 cases and type C in 2 cases by Tile classification. The interval between injury and operation was 6-14 days (mean, 9 days). The preoperative CT images of pelvic fractures were collected. The data was reconstructed by 3D imaging reconstruction workstation. An individualized transiliac crest nail-grafting guide plate was designed on the virtual 3D model. The individualized transiliac crest nail-grafting guide plate and the solid pelvic model were produced with the 3D printing technology. The individualized transiliac crest nail-grafting guide plate was used for intraoperative deep pin position on iliac crest after the preoperative simulation. The follow-up CT scans were used to determine the differences in distance from anterior superior iliac spine, convergence angle, and caudal angle between the preoperative plan and postoperative measurement. Results During the operation, the individualized transiliac crest nail-grafting guide plate was used to guide the placement of 20 pins. X-ray film and CT examination showed that all pins were well positioned. The average depth of pins was 83.16 mm (range, 70.13-100.53 mm). Fitted 3D reconstruction images showed that the entry point and orientation of the pins were all consistent with preoperative schemes. Compared with the planned nail path, there was no significant difference in the distance from anterior superior iliac spine, convergence angle, and caudal angle in the actual nail path (P>0.05). No loosening and rupture of pin, no damage of blood vessels and nerve, and shallow or deep infection occurred during 3 months follow-up, and the incisions healed by first intention. All patients were satisfied with the treatment process. The ranges of motion of hip and knee were normal, and the visual analogue scale (VAS) score was 0-3 (mean, 0.5). Conclusion The individualized transiliac crest nail-grafting guide plate technique is the improvement of traditional technique. It can increase accuracy and effective depth of pin position, enable patients to obtain pelvic mechanical stability quickly after operation, and reduce the risk of complications related to nail path.
ObjectiveTo understand the cervical spine function, core stability and strength of fighter pilots, and to explore the difference of that between fighter pilots with and without neck pain.MethodsFrom October to December 2020, a double-blind design was used to test the cervical spine function, core stability and strength of fighter pilots of a certain part of the Air Force. At the same time, the area of deep cervical flexor and the thickness of transverse abdominis and multifidus muscles were measured. According to the presence or absence of neck pain in the last 3 months, they were divided into neck pain group and non-neck pain group. The cervical spine function, core stability and core strength, deep cervical flexor and transversus abdominis endurance of the two groups were compared and analyzed.ResultsA total of 38 pilots were included. There was no significant difference in age, body mass index, service life, flight time, total flight time and weekly flight time between the neck pain group and the non-neck pain group (P>0.05). There was no significant difference in cervical spine mobility between the two groups of pilots (P>0.05). The cervical flexor muscle strength [(15.5±4.9) vs. (12.1±3.0) N] and the ratio of cervical flexion/neck extension (0.6±0.1 vs. 0.5±0.1) in the non-neck pain group were higher than in the neck pain group (P<0.05). There was no significant difference in the muscle strength of other superficial cervical muscles between the two groups (P>0.05). The average value of deep neck flexor endurance in the neck pain group [25.36 mm Hg(1 mm Hg=0.133 kPa)] better than the non-neck pain group group (17.11 mm Hg) (P=0.026). There was no significant difference in test values of transverse abdominis endurance between the two groups (P>0.05). The left hip internal rotator strength [(11.9±2.6) vs. (10.0±2.1) N] and the left hip external rotator strength [(13.7±2.2) vs. (11.9±2.0) N] in the non-neck pain group were higher than in the neck pain group (P<0.05). There was no significant difference in the muscle strength of the other hip joint muscles between the two groups (P>0.05). The thickness of the right transversus abdominis in the neck pain group [(1.1±0.3) vs. (0.8±0.3) cm] was higher than that in the non-neck pain group (P<0.05). There was no significant difference in the thickness of the left transversus abdominis, the cross-sectional area of deep cervical flexor muscle and the thickness of lumbar multifidus muscle between the two groups (P>0.05).ConclusionsFighter pilots with neck pain have superficial cervical flexor muscle strength and decreased left hip internal and external rotation muscle strength, and the superficial cervical flexor and extensor muscle strength is unbalanced. Strengthening the superficial cervical flexor muscle strength, improving the balance between the superficial cervical flexor and extensor muscles, and enhancing the hip internal and external rotator muscle strength may help prevent neck pain.