Special contoured pelvic brim reconstruction titanium plate combined with trans-plate buttress screws (quadrilateral screws) for acetabular fractures with quadrilateral plate involvement through the anterior ilioinguinal approach.

Background: Managing complicated acetabular fractures involving the quadrilateral plate (QLP) can be challenging for surgeons, especially when complicated by comminution and osteoporosis. Traditional implants do not provide sufficient fixed strength or a proper match. The new-type pre-contoured infrapectineal buttress plates may have drawbacks, such as inaccurate fitting on the medial surface of QLP and an inability to apply reversed compression force to resist medial displacement of femoral head. Therefore, the primary purpose of this study is to introduce a novel technique that utilizes a special contoured pelvic brim reconstruction titanium plate combined with quadrilateral screws to reduce and stabilize acetabular fractures involving the QLP through the ilioinguinal approach. Additionally, the secondary purpose is to evaluate both clinical effectiveness and radiological outcomes of this technique for QLP fractures. Methods: We conducted a retrospective analysis of prospectively collected data from 48 patients (31 males and 17 females) who suffered from acute displaced fractures of the QLP and were treated between January 2012 and December 2019 using a special contoured plate combined with quadrilateral screws. The patients' mean age was 47.56 ± 11.31 years (range: 19-73 years). Fracture patterns included 20 both-column fractures, 12 anterior column and posterior hemitransverse fractures, eight T-type fractures, five transverse fractures and three anterior column fractures with the QLP affected, all of which had femoral head protrusion. Immediate postoperative reduction quality was evaluated according to Matta's criteria. Final clinical functions were assessed during follow-up using the modified Merle d'Aubigné and Harris Hip scores (HHS). Results: The patients were followed up for an average of 48.36 ± 12.94 months (ranging from 24 to 84 months). The mean operative time was 246.08 ± 54.30 min (ranging from 178 to 397 min), and the average blood loss was 715.16 ± 263.84 ml (ranging from 400 to 2000ml). The radiological grading at postoperative stage showed anatomical reduction in 30 patients (62.50%), satisfactory reduction in 14 patients (29.17%), and poor reduction in four patients (8.33%). At the final follow-up, no re-protrusion of the femoral head was observed. In terms of functional outcome, the mean modified Merle d'Aubigné-Postel score was excellent in 26 patients (54.17%), good in 17 patients (35.42%), fair in four patients (8.33%), and poor in one patient (2.08%). The HHS was excellent in 23 patients (47.92%), good in 20 patients (41.67%), fair in four patients (8.33%), and poor in one patient (2.08%). The average HHS was 87.38 ± 7.86 (ranging from 52 to 98). Postoperative complications included lateral femoral cutaneous nerve injury in two patients, delayed wound healing and subsequent development of an inguinal hernia in one patient. Late complications were observed in two patients, with one case of heterotopic ossification and another case of post-traumatic osteoarthritis underwent hip arthroplasty within two years after surgery. Conclusion: Our results indicate that employing the contoured plate specifically designed for QLP injuries, in conjunction with quadrilateral screws through the ilioinguinal approach, can lead to positive outcomes in the treatment of displaced acetabular fractures involving the QLP. This straightforward and efficient technique offers a viable option for surgeons who are managing complex acetabular fractures.

Experimental study on the biomechanical stability of complex acetabular fractures in the quadrilateral area: application of a dynamic anterior titanium-plate screw system.

BACKGROUND AND OBJECTIVE: Complex acetabular fractures involving quadrilateral areas are more challenging to treat during surgery. To date, there has been no ideal internal fixation for these acetabular fractures. The purpose of this study was to evaluate the biomechanical stability of complex acetabular fractures using a dynamic anterior titanium-plate screw system of the quadrilateral area (DAPSQ) by simulating the standing and sitting positions of pelvic specimens. MATERIALS AND METHODS: Eight formal in-preserved cadaveric pelvises aged 30-50 years were selected as the research objects. First, one hip of the normal pelvises was randomly used as the control model (group B) for measurement, and then one hip of the pelvises was randomly selected to make the fracture model in the 8 intact pelvises as the experimental model (group A) for measurement. In group A, acetabular both-column fractures in the quadrilateral area were established, and the fractures were fixed by DAPSQ. The biomechanical testing machine was used to load (simulated physiological load) from 400 N to 700 N at a 1 mm/min speed for 30 s in the vertical direction when the specimens were measured at random in simulated standing or sitting positions in groups. The horizontal displacement and longitudinal displacement of the acetabular fractures in the quadrilateral area were measured in both the standing and sitting simulations. RESULTS: As the load increased, no dislocation or internal fixation breakage occurred during the measurements. In the standing position, the horizontal displacement of the quadrilateral area fractures in group A and group B appeared to be less than 1 mm with loads ranging from 400 N to 700 N, and there was no significant difference between group A and group B (p > 0.05). The longitudinal displacement appeared to be greater than 1 mm with a load of 700 mm in group A (700 N, 2 cases), and the difference was significant between group A and group B (p < 0.05). In the sitting position, the horizontal and longitudinal displacements of the quadrilateral areas were within 0.5 mm in group A and group B, and there was no significant difference between group A and group B (p > 0.05). CONCLUSION: For complex acetabular fractures in the quadrilateral area, DAPSQ fixation may provide early sitting stability, but it is inappropriate for patients to stand too early.

All-inside endoscopic semiautomatic running locked stitch technique shows favourable outcomes for acute Achilles tendon ruptures.

PURPOSE: The safety and reliability of endoscopic Achilles tendon rupture repair are still concerning aspects. This study's aim is to evaluate an all-inside endoscopic semiautomatic running locked stitch (Endo-SARLS) technique. METHODS: Forty cases with acute Achilles tendon rupture were treated with the all-inside Endo-SARLS technique between 2020 and 2021. Under endoscopic control, the proximal tendon stumps were stitched with the running locked method using a semiautomatic flexible suture passer. The threads of the high-strength suture were grasped through the paratenon subspace and then fixed into calcaneal insertion with a knotless anchor. Magnetic resonance imaging (MRI), surgical time and complications were assessed. Achilles Tendon Total Rupture Score (ATRS), Achilles Tendon Resting Angle (ATRA) and Heel Rise Height Scale (HRHS) were utilised to evaluate final outcomes. RESULTS: The average follow-up time was 25.4 ± 0.4 (range: 24-32) months. Appropriate tendon regeneration was observed on MRI after 12 months. At the final follow-up, the median value of ATRS score was 95 (interquartile range: 94, 98). Furthermore, there is no significant difference between the injured and contralateral side in the average ATRA (18.2 ± 1.8 vs. 18.3 ± 1.9°, ns) and median value of HRHS [14.5 (13.3, 15.5) vs. 14.8 (13.5, 15.6) cm, ns]. No infection and nerve injuries were encountered. Thirty-nine patients reported that they resumed casual sports activity after 6 months. One patient had a slight anchor cut-out, due to an addition injury, which was removed after 5 months. CONCLUSIONS: An all-inside Endo-SARLS technique showed promising clinical results for acute Achilles tendon ruptures. This procedure reduces the risk of sural nerve injuries while establishing a reliable connection between the tendon stumps. LEVEL OF EVIDENCE: Level IV.

Tendon stem cells seeded on dynamic chondroitin sulfate and chitosan hydrogel scaffold with BMP2 enhance tendon-to-bone healing.

Failure to adequately reconstruct the tendon-to-bone interface constitutes the primary etiology underlying rotator cuff retear after surgery. The purpose of this study is to construct a dynamic chondroitin sulfate and chitosan hydrogel scaffold (CHS) with bone morphogenetic protein 2 (BMP2), then seed tendon stem cells (TSCs) on BMP2-CHS for the rotator cuff reconstruction of tendon-to-bone interface. In this dynamic hydrogel system, the scaffold could not only have good biocompatibility and degradability but also significantly promote the proliferation and differentiation of TSCs. The ability of BMP2-CHS combined with TSCs to promote regeneration of tendon-to-bone interface was further verified in the rabbit rotator cuff tear model. The results showed that BMP2-CHS combined with TSCs could induce considerable collagen, fibrocartilage, and bone arrangement and growth at the tendon-to-bone interface and promote the biomechanical properties. Overall, TSCs seeded on CHS with BMP2 can enhance tendon-to-bone healing and provide a new possibility for improving the poor prognosis of rotator cuff surgery.

Anterior atlantoaxial motion preservation fixation technique for axis complex fractures (odontoid process with Hangman's fractures) and technique notes.

This study aims to investigate the feasibility and efficacy of anterior atlantoaxial motion preservation fixation (AMPF) in treating axis complex fractures involving the odontoid process fracture and Hangman's fractures with C2/3 instability. A retrospective study was conducted on eight patients who underwent AMPF for axis complex fractures at the General Hospital of Central Theater Command from February 2004 to October 2021. The types of axis injuries, reasons for injuries, surgery time, intraoperative blood loss, spinal cord injury classification (American Spinal Injury Association, ASIA), as well as complications and technical notes, were documented. This study included eight cases of type II Hangman's fracture, five cases of type II and three cases of type III odontoid process fracture. Five patients experienced traffic accidents, while three patients experienced falling injuries. All patients underwent AMPF surgery with an average intraoperative blood loss of 288.75 mL and a duration of 174.5 min. Two patients experienced dysphagia 1 month after surgery. The patients were followed up for an average of 15.63 months. One case improved from C to E in terms of neurological condition, three cases improved from D to E, and four cases remained at E. Bony fusion and Atlantoaxial Motion Preservation were successfully achieved for all eight patients. AMPF is a feasible and effective way for simultaneous odontoid process fracture and Hangman's fractures with C2/3 instability, while preserving atlantoaxial movement.

Inclined angles of acetabular quadrilateral plate: digital measurement and clinical application of the new anatomical concept.

PURPOSE: Matta scoring standard is one of the most frequently used postoperative imaging evaluations for acetabular fracture reduction, but has obvious shortcomings. This study, for the first time, proposed the concept of inclined angles of acetabular quadrilateral plate. The purpose of this study was to investigate the normal range of the inclined angles in adults by digital measurement and explore the feasibility of using them to evaluate the reduction quality of acetabular quadrilateral fractures after surgery. METHODS: Firstly, the pelvic CT three-dimensional reconstruction data of 40 healthy adults including 20 males and 20 females were collected. The normal range of the anterior, middle, and posterior inclined angles were measured via Mimics software. Secondly, a modified Matta criteria that combined the classic Matta criteria and evaluation criteria of the inclined angles was proposed. And we classified modified Matta criteria into three grades including excellent, good and poor. Finally, a total of 125 cases with quadrilateral plate fractures was included and the postoperative CT data were analyzed by using both the classic Matta criteria and our modified Matta criteria. Then, the accuracy and consistency of both criteria to evaluate postoperative hip function was investigated. RESULTS: The average anterior inclined angle: male (97.11° ± 2.59°), female (90.63° ± 2.09°); middle inclined angle: male (105.57° ± 1.93°), female (100.64° ± 2.46°); and posterior inclined angle: male (112.62° ± 2.54), female (106.37° ± 2.53°). Whether in males or in females, the anterior, middle, and posterior inclined angles showed a progressively increasing trend. All the three inclined angles in males were all significantly larger than those in females (p < 0.05). Among 125 cases with quadrilateral plate fractures, 101 cases (80.8%) were graded as excellent, 18 cases (14.4%) as good, and 6 cases (4.8%) as poor according to the classic Matta criteria. While based on modified Matta criteria, there were excellent in 37 cases (29.6%), good in 76 cases (60.8%), and poor in 12 cases (9.6%). According to the Harris hip score system, the functional outcomes were excellent in 59 cases (47.2%), good in 26 cases (20.8%), fair in 24 cases (19.2%), and poor in 16 cases (12.8%). Our results showed that among the cases evaluated as excellent according to the classic Matta criteria and modified Matta criteria, the excellent-to-good rates of hip function were 70.3% and 78.4%, respectively. And among the cases evaluated as poor according to the modified Matta criteria, the fair-to-poor rate of hip function was 75%, while this value was 50% for classic Matta criteria. Both differences were statistically significant (p < 0.05). CONCLUSION: Inclined angles of the quadrilateral plate could be used to assess the quality of fracture reduction and provide a basis for evaluating the rotational displacement of fracture blocks in the quadrilateral plate, which compensates the shortage of classic Matta criteria.

Three-Dimensional Printed Plate Template Versus Hemipelvis Model in Patient-Specific Plate Preparation for Posterior Wall Acetabular Fractures.

OBJECTIVE: The application of three-dimensional (3D) printing technology in the management of posterior wall acetabular fractures can greatly reduce surgical invasiveness and operative time and simplify the procedure of reconstruction plate contouring, but the cost and time of patient-specific plate preparation on the basis of traditional 3D-printed pelvis model should not be neglected. We described a new method for patient-specific plate preparation by using 3D-printed plate template. The study aimed to assess the effectiveness and feasibility of the 3D-printed plate template in patient-specific plate preparation for posterior wall acetabular fractures. METHODS: A total of 65 cases of posterior wall acetabular fractures with surgical treatment from December 2012 to December 2020 were chosen. According to the different plate contouring methods, the 65 cases were divided into three groups, which were group A (21 cases), group B (20 cases), and group C (24 cases). In group A, the 3D-printed plate template was used to contour the patient-specific reconstruction plate before surgery, whereas the 3D-printed hemipelvis model was adopted for group B. In group C, the reconstruction plate was contoured intraoperatively. Among the three groups, the instrumentation time, surgical time, blood loss, patient-specific plate preparation time, complications, reduction quality, and hip function were compared. The Kruskal-Wallis test was used to analyze the reduction quality and hip function among three groups. RESULTS: In comparison with group C, patients in groups A and B were featured by obviously shorter instrumentation time (-22, -23 min), shorter surgical time (-46, -44 min), and less intraoperative blood loss (-110, -122 mL). Compared to the hemipelvis model in group B (2.29 ± 0.56 vs. 12.70 ± 3.79 days), the 3D printing time for plate templates in group A was significantly shorter. The reduction quality and hip function had no obvious statistical difference among the three groups. The complication rate within group A (3/21) and group B (3/20) were both slightly lower than group C (5/24), with no obvious difference. CONCLUSIONS: Both the patient-specific pre-contoured plate fixation methods based on the 3D-printed hemipelvis model and plate template can achieve satisfactory clinical efficacy, with the advantage of shorter instrumentation and surgical time, and less intraoperative blood loss. However, 3D printing of plate template is easier and less time-consuming, considering the shorter time and less cost for 3D printing of physical model.

Third-Generation Dynamic Anterior Plate-Screw System for Quadrilateral Fractures: Digital Design Based on 834 Pelvic Measurements.

Background and Objectives: To investigate the digital measurement method for the plate trajectory of dynamic anterior plate-screw system for quadrilateral plate (DAPSQ), and then design a third-generation DAPSQ plate that conforms to the needs of the Chinese population through collating a large sample anatomical data. Materials and Methods: Firstly, the length of the pubic region, quadrilateral region, iliac region, and the total length of the DAPSQ trajectory were measured by a digital measurement approach in 22 complete pelvic specimens. Then, the results were compared with the direct measurement of pelvic specimens to verify the reliability of the digital measurement method. Secondly, 504 cases (834 hemilateral pelvis) of adult pelvic CT images were collected from four medical centers in China. The four DAPSQ trajectory parameters were obtained with the digital measurement method. Finally, the third-generation DAPSQ plate was designed, and its applicability was verified. Results: There was no statistically significant difference in the four trajectory parameters when comparing the direct measurement method with the digital measurement method (p > 0.05). The average lengths of the pubic region, quadrilateral region, iliac region, and the total length in Chinese population were (60.96 ± 5.39) mm, (69.11 ± 5.28) mm, (84.40 ± 6.41) mm, and (214.46 ± 10.15) mm, respectively. Based on the measurement results, six models of the DAPSQ plate including small size (A1,A2), medium size (B1,B2), and the large size (C1,C2) were designed. The verification experiment showed that all these six type plates could meet the requirement of 94.36% cases. Conclusions: A reliable computerized method for measuring irregular pelvic structure was proposed, which not only provided an anatomical basis for the design of the third-generation DAPSQ plate, but also provided a reference for the design of other pelvic fixation devices.

The association between paraspinal muscle degeneration and osteoporotic vertebral compression fracture severity in postmenopausal women.

BACKGROUND: According to reports in the literature, osteoporotic vertebral compression fracture (OVCF) is associated with paraspinal muscle degeneration; however, the association between the severity of OVCF and paraspinal muscle degeneration is not clear. OBJECTIVE: The purpose of this study was to investigate the association between paraspinal muscle degeneration and OVCF severity in postmenopausal women. METHODS: Three hundred and seventy-six MRI images from 47 patients were collected and analyzed. Sagittal and axial coronal T2-weighted images were used to measure the fractured vertebra sagittal cross-sectional area (FSCSA), the adjacent normal vertebral body sagittal cross-sectional area (NSCSA), paraspinal muscle cross-sectional area (CSA), and the fat cross-sectional area (FCSA). The ratio of fractured vertebra compressed sagittal cross-sectional area (RCSA) and fatty infiltration ratio (FIR) was subsequently calculated. The formulas for RCSA and FIR calculations are as follows: RCSA = (NSCSA-FSCSA)/NSCSA; FIR = FCSA/CSA. RCSA and FIR represent the severity of OVCF and paraspinal muscle degeneration, respectively. RESULTS: The correlation between paraspinal muscle degeneration and OVCF severity was analyzed using the Pearson correlation, and multiple regression analysis was performed to explore related risk factors. OVCF severity was closely associated with paraspinal muscle degeneration (L3/4 FIR r= 0.704, P< 0.05; L4/5 FIR r= 0.578, P< 0.05; L5/S1 FIR r= 0.581, P< 0.05). Multiple regression analysis demonstrated that the risk factor for OVCF severity was L3/4 FIR (ß= 0.421, P= 0.033). CONCLUSION: OVCF severity was associated with the FIR of paraspinal muscles, and L3/4 FIR was a predictive factor for OVCF severity in postmenopausal women.