[Clinical analysis of posterior axillary approach internal fixation for Idebergâ a andâ ¡glenoid fractures].

OBJECTIVE: To investigate the efficacy of posterior axillary approach internal fixation for Ideberg Ⅰa andⅡ glenoid fractures. METHODS: From December 2018 to September 2021, 9 patients with lower part of glenoid fractures were treated by posterior axillary approach, including 3 males and 6 females, aged from 50 to 78 years old. All the fractures were closed fractures. According to Ideberg type of scapular glenoid fracture was type Ⅰa in 6 cases and type Ⅱ in 3 cases. AP and lateral X-ray films of scapula were taken at 6, 12 weeks and 6 and 12 months postoperatively. Constant-Murley and disabilities of the arm shoulder and hand (DASH), and other complications were recorded at the latest follow-up. RESULTS: Nine patients were followed up, ranged from 6 to 15 months. And bone healing was achieved in all 9 patients at the final follow-up, the healing time 3 to 6 months, Constant-Murley score at the final follow-up ranged from 55 to 96, and DASH score ranged from 3.33 to 33.33. Both of them were better than preoperative. CONCLUSION: The posterior axillary approach internal fixation for Ideberg Ⅰa and Ideberg Ⅱ Glenoid fractures scapular fracture is satisfactory and worthy of clinical application.

Study on seismic vulnerability analysis of the interaction system between saturated soft soil and subway station structures.

The seismic vulnerability of interaction system of saturated soft soil and subway station structures was explored in this paper. The coupled nonlinear numerical models of interaction system were established using the u-p formulation of Biot's theory to describe the saturated two-phase media. A refined finite element model of interaction system was developed to study its nonlinear seismic responses and seismic hazard mechanism. In this study, the multi-yield elastoplastic constitutive model was adopted for the soil, while a fiber section elastoplastic constitutive model was used for the structure. The seismic response of the structure was calculated by inputting the artificial seismic wave obtained from the power spectrum-triangular series method. The maximum inter-story drift angle was taken as a structural performance parameter for the subway station structure. The structural demand cloud was obtained under random ground motion sequences. Based on the probabilistic seismic demand model analysis method, the seismic vulnerability curve of the subway station structure was plotted, and the seismic vulnerability curve was analyzed as per the vulnerability of performance parameters. With the increase of soil strength, the vulnerability index of subway station structure under different peak acceleration ground motion decreased correspondingly. Based on the above vulnerability theory and analysis methods, it can be found from the above vulnerability theory and analysis methods that the subway station structure with established buried depth in saturated soft soil site exhibits a certain degree of safety and reliability, and can meet the seismic fortification goal of "no damage in small earthquakes, repairable in medium earthquakes and no collapse in large earthquakes". The results of vulnerability analysis are in line with the actual seismic survey, and the vulnerability analysis method proposed in this paper can be applied to the vulnerability analysis of underground structures on saturated soft soil foundation.

Clinical comparison of single-incision and dual-incision approaches for the treatment of distal tibial and fibular fractures: A randomized controlled trial.

PURPOSE: The purpose of this study was to clinically compare the single-incision and dual-incision approaches for the treatment of distal tibial and fibular fractures. METHODS: In total, 93 patients were enrolled, and the mean follow-up was 15 months (range 12-19 months). The patients treated for open reduction and internal fixation were randomly classified into two groups based on the approach used: 45 patients were treated using the single-incision approach (group 1) and 48 patients were treated using the dual-incision approach (group 2). In these two groups, operation time, discharge time, postoperative complications, and ankle function evaluations (Olerud-Molander Ankle Score) were compared between the two groups. RESULTS: There were no significant differences in the mean operation time (98.2 ± 18.5 vs. 103.6 ± 19.3), discharge time (11.1 ± 3.9 vs. 12.5 ± 5.7), overall surgical complication rates (9/45 vs. 15/48), or ankle function between the two groups (p > 0.05). However, the rate of soft tissue-related complications, such as skin slough, infection, nonunion, and delayed union, was significantly lower in group 1 (5/45) than in group 2 (14/48) (p < 0.05). CONCLUSION: The two incision approaches were found to have similar clinical outcomes. However, with regard to soft tissue conservation, the single-incision approach was superior to the dual-incision and maybe a reliable alternative.

MiR-143 Inhibits Osteoclastogenesis by Targeting RANK and NF-κB and MAPK Signaling Pathways.

OBJECTIVE: To explore the effect of miRNA-143 on osteoclast formation and provide new ideas for the treatment of osteoporosis. METHODS: Mice macrophage lines RAW264.7 cells after transfection were divided into four groups: control group, RANKL group, RANKL combined with miR-143 mimics group and RANKL combined with miR-NC group. TARCP staining was used to observe the effect of miR-143 on osteoclast formation. The expression of RANK, TRAF6 and NFATc-1 in the upstream of RANKL pathway was detected by real-time quantitative PCR (RT qPCR) and Western blotting (WB). The binding of miR-143 to TNFRSF11A was detected by double Luciferase Reporter Analysis. The effect of miR-143 on the expression of NF-κB (p65, I-κB-α) signal pathway in osteoclasts was detected. The effects of I-BET151 on the expression of osteoclast-specific genes TRACP, MMP 9, CtsK and c-Src were detected. RESULTS: The positive level of osteoclasts in RANKL group and RANKL combined with miR-NC group was significantly higher than that of RANKL combined with miR-143 mimics group and control group (P < 0.05). The expression levels of RANK, TRAF6, NFATc-1, TRACP, MMP-9, CtsK and c-Src in RANKL group and RANKL combined with miR-NC group were significantly higher than those of RANKL combined with miR-143 mimics group and control group (P < 0.05). The expression levels of I-κB-α were significantly lower than that of RANKL combined with miR-143 mimics group and control group (P<0.05). CONCLUSION: MiR-143 can inhibit the expression of RANK, TRAF6 and downstream NFATc-1 in the RANKL pathway, thereby inhibiting the RANK/RANKL pathway. MiR-143 can inhibit the signal pathway of NF-κB (p65, I-κB-α). MiR-143 inhibits the expression of osteoclast-specific genes TRACP, MMP 9, CtsK and c-Src. That is to say, miR-143 inhibits osteoclast formation by targeting RANK, NF- κB and MAPK signaling pathways.

Patient-derived Heterogeneous Xenograft Model of Pancreatic Cancer Using Zebrafish Larvae as Hosts for Comparative Drug Assessment.

Patient-derived tumor xenograft (PDX) and cell-derived tumor xenograft (CDX) are important techniques for preclinical assessment, medication guidance and basic cancer researches. Generations of PDX models in traditional host mice are time-consuming and only working for a small proportion of samples. Recently, zebrafish PDX (zPDX) has emerged as a unique host system, with the characteristics of small-scale and high efficiency. Here, we describe an optimized methodology for generating a dual fluorescence-labeled tumor xenograft model for comparative chemotherapy assessment in zPDX models. Tumor cells and fibroblasts were enriched from freshly-harvested or frozen pancreatic cancer tissue at different culture conditions. Both cell groups were labeled by lentivirus expressing green or red fluorescent proteins, as well as an anti-apoptosis gene BCL2L1. The transfected cells were pre-mixed and co-injected into the 2 dpf larval zebrafish that were then bred in modified E3 medium at 32 °C. The xenograft models were treated by chemotherapy drugs and/or BCL2L1 inhibitor, and the viabilities of both tumor cells and fibroblasts were investigated simultaneously. In summary, this protocol allows researchers to quickly generate a large amount of zPDX models with a heterogeneous tumor microenvironment and provides a longer observation window and a more precise quantitation in assessing the efficiency of drug candidates.

[Surgical methods and curative effect of tibial plateau fracture with medial large block split].

OBJECTIVE: To explore the clinical effects of protecting the internal structure of the knee and internal fixation through two different directions for the treatment of tibial plateau fractures with medial large block split. METHODS: From January 2010 to January 2016, data of 21 patients of tibial plateau with medial large block split fractures who were treated with protecting the internal structure of the knee and internal fixation through two different directions were retrospectively analyzed, including 17 males and 4 females, with an average age of (39.2±3.2) years old ranging from 27 to 63 years. Anteroposterior and lateral radiographs as well as computed tomography(CT) images were obtained in the course of preoperative. It was made in the operation to protect medial knee structure, combining with internal fixation via two different directions plates(medial and posteromedial). If the posterolateral condyle fracture was involved, a plate was applied through posterolateral approach. Rasmussen score was used for radiological assessment, and HSS knee score was used for efficacy assessment at 1 year after operation. The fracture healing time was judged by X-ray and clinical examinations, additionally, the complications and corresponding outcomes were also recorded. RESULTS: All patients were followed up for 10 to 24 months with an average of(17.2±1.7) months. All fractures were healed, the healing time was 9 to 16 weeks with an average of(11.1±3.2) weeks. The Rasmussen score after surgery was 1 to 18 points with an average of(16.7±1.5) points. Sixteen cases got excellent, 3 good and 2 fair. At the final follow-up, HSS functional scores ranged from 60 to 100 points with an average of (87.3±6.7) points, the result was excellent in 18 cases, good in 2 cases and fair in 1 case. CONCLUSIONS: For a split fracture of the medial tibial plateau, the medial incision, full protection of the medial knee structure, and two different directions of supporting plate fixation are feasible, and the short-term effect is satisfactory.

Distal tibial fracture: An ideal indication for external fixation using locking plate.

OBJECTIVE: To evaluate the feasibility and efficiency of one-stage external fixation by using locking plate in distal tibial fractures. METHODS: In this non-control prospective study, 28 patients with distal tibial fractures were included and underwent one-stage external fixation by using locking plate. There were 21 males and 7 females, with a mean age of 43 years (19-63). According to AO/OTA fracture classification, there were 9 cases of Type A1, 9 of Type A2, 10 of Type A3 fractures. There were 21 close and 7 open fractures. The locking plate was placed on the anteromedial aspect of the tibia with 4-5 bicortical screws inserted in both distal met- aphysis and diaphysis. The radiographic and clinic results were evaluated. RESULTS: All patients were followed up for the average of 16 months (ranging from 12 to 21 months). The average surgery duration was 38 (25-60) minutes. The mean time to fracture healing were 14.6 ± 2.67, 17.5 ± 3.66, and 18.4 ± 3.37 (p < 0.05) weeks in type A1, A2, and A3 fractures respectively. By the end of the follow-ups, the mean AOFAS score were 96.11 ± 2.32, 92.67 ± 1.80 and 92.00 ± 2.06 (p > 0.05) in type A1, A2, and A3 fractures respectively. None of nonunion, deep infection, or breakage of screw or plate were observed. CONCLUSIONS: Distal tibial fracture was the ideal indication for external fixation using locking plate. The external plating is characterized by ease of performance, less invasive, fewer soft tissue impingement, improved cosmesis, and convenient for removal.

Evaluation of Partial Cut-out of Sacroiliac Screws From the Sacral Ala Slope via Pelvic Inlet and Outlet View.

STUDY DESIGN: An anatomic and radiographic study of placement of sacroiliac screws. OBJECTIVE: The aim of this study was to quantitatively assess the risk of partial cut-out of sacroiliac screws from the sacral ala slope via inlet and outlet view. SUMMARY OF BACKGROUND DATA: The partial cut-out of sacroiliac screws from the superior surface of sacral ala can jeopardize the L5 nerve root, which is difficult to identify on the pelvic inlet and outlet views. METHODS: Computed tomography images of 60 patients without pelvic ring deformity or injury were used to measure the width (on inlet view) and height (on outlet view) of the sacral ala. The angle of the sacral ala slope was measured on lateral view. According to the measured parameters, the theoretical safe trajectories of screw placement were calculated using inverse trigonometric functions. Under fluoroscopic guidance, a sacroiliac screw was placed close to the midline on both inlet and outlet views, including posterosuperior, posteroinferior, anterosuperior, and anteroinferior regions to the midline. The incidence of screw partial cut-out from the superior surface of sacral ala was identified. RESULTS: The measured widths and heights of the sacral alas were 28.1 ± 2.8 and 29.8 ± 3.1 mm, respectively. The average angle between the superior aspect of the S1 vertebral body and the superior aspect of the sacral ala was 37.2 ± 2.5 degrees. The rate of partial cut-out of the screws from the superior surface of sacral ala slope was 12.5% (5/40) in posterosuperior, 0% (0/40) in posteroinferior, 70% (28/40) in anterosuperior, and 20% (8/40) in anteroinferior. CONCLUSION: To avoid the risk of partial cut-out from sacroiliac screw placement, more precise description should be added to the conventional description: the sacroiliac screws should be placed at the inferior half portion on outlet view and at the posterior half portion on inlet view. LEVEL OF EVIDENCE: 4.

External Fixation Using a Locking Plate: A Reliable Way in Treating Distal Tibial Fractures.

The surgical treatment of distal tibial fractures is still challenging. The purpose of this study was to evaluate the clinical and radiographic results associated with the use of a precontoured distal femoral locking plate as an external fixator in treating distal tibial fractures. From August 2011 to October 2012, 28 patients with distal tibial fractures were consecutively enrolled in this study. There were 9 OTA 43.A1, 9 43.A2, and 10 43.A3, including 21 closed and 7 open fractures. The precontoured distal femoral locking plate was placed on the anteromedial aspect of the tibia as an external fixator. All patients were followed for an average of 16 months. The mean surgical duration was 38 (25-60) minutes. The mean time until fracture healing was 16.7 (12-24) weeks. At final follow-up, the mean American Orthopaedic Foot and Ankle Society score was 93 (88-100). There were no nonunions, deep infections, or implant fractures. Three patients had transient superficial pin site infection, but these did not change the clinical outcome. External fixation using a precontoured distal femoral locking plate is a reliable option in treating distal tibial fracture. The procedure is easy to perform, is less invasive, and the low profile plate can be concealed under stockings and can be conveniently removed.

One-Stage External Fixation Using a Locking Plate: Experience in 116 Tibial Fractures.

The authors report the results of 1-stage external fixation using a locking plate in 116 tibial fractures (85 closed and 31 open). The patients were followed for an average of 22 months. The mean duration of surgery was 42 minutes. The mean fracture healing time was 12 weeks for proximal, 20 weeks for shaft, 14 weeks for distal, and 24 weeks for multisegmental tibial fractures. Nonunion, deep infection, and breakage of screws did not occur. External plate fixation is effective for tibial fractures and especially for metaphyseal fractures. It has the advantages of being easy to perform and less invasive, and the plate is conveniently located for removal.

External fixation using femoral less invasive stabilization system plate in tibial proximal metaphyseal fracture.

BACKGROUND: The locking plates are often used for internal fixation of closed tibial fractures. The use of a locking plate as an external fixator is still controversial, particularly for closed fractures. The purpose of this study is to evaluate the results of external fixation using the femoral less invasive stabilization system (LISS) plate in proximal metaphyseal fractures of the tibia. METHODS: We prospectively evaluated 35 patients (26 males and 9 females) with a mean age of 42 years (range, 21 to 62 years) who presented with fresh tibial proximal metaphyseal fractures. According to the AO Foundation and Orthopaedic Trauma Association (AO/OTA) classification, the fractures were identified as type 41-A2 in 18 cases and type 41-A3 in 17 cases, including 25 closed fractures and 10 open fractures. The femoral LISS plate was used to fix these fractures, which was placed on the anteromedial aspect of the tibia as an external fixator. The mean follow-up period was 18 months (range, 13 to 22 months). RESULTS: All fractures healed in a mean time of 14 weeks (range, 10 to 20 weeks). There was no case of nonunion, deep infection, and loosening of screws and plates. One month after the appearance of cortical bridging on biplanar radiographs, the locking plate was removed within 3 minutes in the clinic without any difficulty. According to the Hospital for Special Surgery (HSS) knee scoring system and American Orthopaedic Foot & Ankle Society (AOFAS) ankle scoring system, the mean HSS score was 91 (range, 85 to 100) and 98 (range, 93 to 100), and the mean AOFAS score was 94 (range, 90 to 100) and 98 (range, 95 to 100) at 4 weeks postoperatively and final follow-up, respectively. CONCLUSIONS: For proximal metaphyseal fracture of the tibia, external fixation using the femoral LISS plate is a safe and reliable technique with minimal complications and excellent outcomes. Its advantages include ease of performing the surgery, use of a less invasive technique, and convenience of plate removal after fracture healing.

External fixation using locking plate in distal tibial fracture: a finite element analysis.

BACKGROUND: External fixation of tibial fractures using a locking plate has been reported with favorable results in some selected patients. However, the stability of external plate fixation in this fracture pattern has not been previously demonstrated. We investigated the stability of external plate fixation with different plate-bone distances. METHODS: In this study, the computational processing model of external fixation of a distal tibial metaphyseal fracture utilizing the contralateral femoral less invasive stabilization system plate was analyzed. The plate was placed on the anteromedial aspect of tibia with different plate-bone distances: 1, 10, 20, and 30 mm. RESULTS: Under axial load, the stiffness of construct in all groups was higher than intact tibia. Under axial load with an internal rotational force, the stiffness of construct with 1 and 10 mm plate-bone distances was similar to that of an intact tibia and the stiffness of the construct with 20 and 30 mm distances was lower than that of an intact tibia. Under axial load with an external rotational force, the stiffness of the construct in all groups was lower than that of an intact tibia. The maximum plate stresses were concentrated at the two most distal screws and were highest in the construct with the 10 mm plate-bone distance, and least in the construct with a 1 mm plate-bone distance. CONCLUSIONS: To guarantee a stable external plate fixation in distal tibial fracture, the plate-bone distance should be less than 30 mm.

Surgical treatment of extra-articular or simple intra-articular distal tibial fractures: MIPO versus supercutaneous plating.

Minimally invasive plate osteosynthesis (MIPO) has become a widely accepted technique to treat distal tibial fractures. Recently, the novel application of a locking plate used as an external fixator (supercutaneous plating) was introduced for the management of open fractures and infected nonunions and even as an adjunct in distraction osteogenesis, which is considered another less invasive method. The aim of this study was to compare the results of supercutaneous plating with closed reduction and minimally invasive plating in the treatment of distal tibial fractures. Forty-eight matched patients were divided according to age, sex, Injury Severity Score, and fracture pattern into the MIPO group and the supercutaneous plating group. Minimum follow-up was 12 months (mean, 18.5 months; range, 12-26 months). No patient had nonunion, hardware breakdown, or deep infection. Patients in the supercutaneous plating group had a significantly shorter mean operative time (65.6±13.2 vs 85.9±14.0 minutes; P=.000), hospital stay (7.5±2.0 vs 13.0±4.4 days; P=.000), and union time (15.2±2.4 vs 17.0±2.8 weeks; P=.000). In the MIPO group, 15 (62.5%) patients reported implant impingement or discomfort and there was 1 incidence of stripping of 15.6% at the time of locking screw removal, whereas in the supercutaneous plating group, no patient reported skin irritation, and removal of the supercutaneous plate was easily performed in clinic without anesthesia. Distal tibial fractures may be treated successfully with MIPO or supercutaneous plating. However, the supercutaneous plating technique may represent a superior surgical option because it offers advantages in terms of mean operative time, hospital stay, and union time; skin irritation; and implant removal.

Treatment of segmental tibial fractures with supercutaneous plating.

Segmental tibial fractures usually follow a high-energy trauma and are often associated with many complications. The purpose of this report is to describe the authors' results in the treatment of segmental tibial fractures with supercutaneous locking plates used as external fixators. Between January 2009 and March 2012, a total of 20 patients underwent external plating (supercutaneous plating) of the segmental tibial fractures using a less-invasive stabilization system locking plate (Synthes, Paoli, Pennsylvania). Six fractures were closed and 14 were open (6 grade IIIa, 2 grade IIIb, 4 grade II, and 2 grade I, according to the Gustilo classification). When imaging studies confirmed bone union, the plates and screws were removed in the outpatient clinic. Average time of follow-up was 23 months (range, 12-47 months). All fractures achieved union. Median time to union was 19 weeks (range, 12-40 weeks) for the proximal fractures and 22 weeks (range, 12-42 weeks) for the distal fractures. Functional results were excellent in 17 patients and good in 3. Delayed union of the fracture occurred in 2 patients. All patients' radiographs showed normal alignment. No rotational deformities and leg shortening were seen. No incidences of deep infection or implant failures occurred. Minor screw tract infection occurred in 2 patients. A new 1-stage protocol using supercutaneous plating as a definitive fixator for segmental tibial fractures is less invasive, has a lower cost, and has a shorter hospitalization time. Surgeons can achieve good reduction, soft tissue reconstruction, stable fixation, and high union rates using supercutaneous plating. The current patients obtained excellent knee and ankle joint motion and good functional outcomes and had a comfortable clinical course.

Operative treatment of acromioclavicular joint dislocation: a new technique with suture anchors.

OBJECTIVE: To evaluate clinical outcome of suture anchors in strengthening both acromioclavicular and coracoclavicular ligaments in the surgical treatment of acromioclavicular joint dislocation. METHODS: Twenty-eight patients with acute traumatic Rockwood III, IV and V dislocations of the acromioclavicular joint surgically treated at our institute between October 2010 and January 2012 were recruited.All patients underwent open reduction combined with suture anchors. Function was evaluated using the Constant- Murley shoulder score. Clinical and radiographic shoulder ratings were evaluated using Taft criteria at 3, 6 and 12 months. RESULTS: Two cases with fixation loosening were not included in final statistical analysis. Other patients obtained full joint reposition on immediate postoperative radiographs. Follow-up was performed with an average of 15.6 months (range, 12-19). After early range of motion exercises, 96.2% of the patients (25/26) could abduct and elevate their shoulders more than 90 degrees within postoperative 3 months. There was no infection. Average Constant-Murley score was 96.3 points (range, 94-100) and mean Taft shoulder rating was 10.7 points (range, 8-12) at 12 months. CONCLUSION: The suture anchor is a relatively simple technique and can avoid screw removal which is helpful in reconstructing both acromioclavicular and coracoclavicular ligaments in acute traumatic acromioclavicular joint dislocation.

[Curative efficacies of mini-invasive percutaneous osteosynthesis versus supercutaneous plating for distal tibial fractures].

OBJECTIVE: To compare the clinical efficacies of mini-invasive percutaneous osteosynthesis (MIPO) versus supercutaneous plating with closed reduction in the treatment of distal tibial fractures. METHODS: A total of 48 patients with close distal tibial fractures were treated between January 2010 and January 2012. The MIPO group included 16 males and 8 females with an average age of 36 years. And the types were A (n = 15), B (n = 6) and C (n = 3) according to the classification scheme of Association for the Study of Internal Fixation (AO/ASIF). The supercutaneous plating group also included 16 males and 8 females with an average age of 37 years. And the types were A (n = 15), B (n = 6) and C (n = 3). And the operative duration, hospital stay, union time, postoperative complications and function of ankle were compared between two groups. RESULTS: The mean follow-up period was 18.5 (12-26) months. There was no instance of nonunion, hardware breakdown or deep infection. Patients in supercutaneous plating group had significantly shorter mean operative duration, hospital stay and union time. Three patients and 1 patient in MIPO group presented with superficial infection and delayed union respectively while there was no occurrence in supercutaneous plating group. And the differences were not statistically significant. Fifteen patients (62.5%) complained of implant impingement or discomfort. And stripping occurred at an incidence of 15.6% during the removal time of locking screws in MIPO group. While in supercutaneous plating group, there as no complaint of skin irritation and removal of supercutaneous plate was easily performed without anesthesia. The mean AOFAS score was 90.7 ± 3.8 in supercutaneous plating group versus 88.9 ± 4.1 in MIPO group (P = 0.070). CONCLUSION: Distal tibia fractures may be treated successfully with MIPO or supercutaneous plating. However, supercutaneous plating offers multiple advantages in terms of mean operative duration, hospital stay, union time, skin irritation and implant removal.

The operative treatment of complex pilon fractures: A strategy of soft tissue control.

BACKGROUND: Pilon fractures are challenging to manage because of the complexity of the injury pattern and the risk of significant complications. The soft tissue injury and handling of the soft tissue envelope are crucial in pilon fracture outcomes. The purpose of this study was to evaluate the early rate of complications using the strategy of "soft tissue control" for operative treatment of complex pilon fractures. MATERIALS AND METHODS: 36 complex pilon fractures were treated with the "soft tissue control" strategy. Patients followed the standard staged protocol, anterolateral approach to the distal tibia, the "no-touch" technique and incisional negative pressure wound therapy for pilon fractures. Patients were examined clinically at 2-3 weeks and then 8 weeks for complications associated with the surgical technique. RESULTS: All fractures were AO/OTA (Orthopaedic Trauma Association) type C fractures (61% C3, 22% C2 and 16% C1). Only one patient developed superficial infection and resolved with antibiotics and local wound care. None developed deep infection. CONCLUSIONS: The strategy of soft tissue control for treatment of pilon fractures resulted in relatively low incidence of early wound complications in patients with complex pilon fractures.

A posterior inverted L-shaped approach for the treatment of posterior bicondylar tibial plateau fractures.

OBJECTIVES: To present a case series of patients with posterior bicondylar tibial plateau fractures treated by direct exposure and buttress plate fixation through posterior inverted L-shaped approach. METHODS: Between August 2007 and July 2010, eight middle aged patients were identified to have posterior bicondylar tibial plateau fractures. All the eight patients underwent direct fracture exposure, reduction under visualization, and buttress plate fixation through posterior inverted L-shaped approach. RESULTS: All the cases were followed for an average of 28.1 months (24-36 months). All the cases had satisfactory reduction except one case, which had a 3-mm stepoff postoperatively. None of the complications such as infection, necrosis of the skin incision or the loosening and breakage of the internal fixator occurred. The average radiographic bony union time and full weightbearing time were 11.5 weeks (10-14 weeks), and 13.8 weeks (11-17 weeks) respectively. The average range of motion of the affected knee was from 3.6° to 127.8° at 1 year after the operation. CONCLUSIONS: The posterior inverted L-shaped approach would not involve osteotomy, tendotomy or division of muscles, while allowing satisfied visualization of the entire posterior aspect of tibial plateau and appropriate placement of hardware. This approach is a safe and effective way for the treatment of posterior bicondylar tibial plateau fractures.

Biomechanical study of the atlantoaxial joint after artificial atlanto-odontoid joint arthroplasty.

OBJECTIVE: To investigate the stability and three-dimensional movements of the atlantoaxial joint after artificial atlanto-odontoid joint (AAOJ) arthroplasty by comparing with a conventional method. METHODS: After anterior decompression, 24 human cadaveric spinal specimens of C0-C3 were randomly divided into two groups: Group A receiving artificial AAOJ arthroplasty; Group B experiencing anterior transarticular screw (ATAS) fixation. Two groups underwent flexibility test in intact and instrumented states. Rotational angle of the C0-C3 segments was measured to study the immediate stability and function of anterior decompression with AAOJ arthroplasty compared with the intact state and ATAS fixation. RESULTS: Compared with the intact state, anterior decompression with AAOJ arthroplasty resulted in a significant decrease in the range of motion (ROM) and neutral zone (NZ) during flexion, extension and lateral bending (P less than 0.05); however, with regard to axial rotation, there was no significant difference in ROM and NZ (P larger than 0.05). Compared with anterior decompression with ATAS fixation, anterior decompression with AAOJ arthroplasty during flexion, extension and lateral bending, significant difference was found in ROM and NZ (P larger than 0.05); however, as for axial rotation, there was a significant increase in ROM and NZ (P less than 0.05). CONCLUSION: The self-designed AAOJ has an excellent biomechanical performance, which can restore excellent instant stability and preserve the movement of the atlantoaxial joint.

[Application of vacuum sealing drainage in open ankle fracture and dislocation].

OBJECTIVE: To investigate therapeutic effects of vacuum sealing drainage (VSD) in the treatment of soft tissue defect combined with tendon and bone exposure. METHODS: From October 2007 to February 2011, 397 patients (412 feet) with open ankle fracture and dislocation combined with soft tissue defected were treated by VSD. There were 301 males and 96 females with an average age of 36 years (ranging age from 20 to 73 years). According to AO classification, 74 feet were type I, 211 feet were type II, 108 feet were type III and 19 feet were type IV. The mean time from injury to operation was 5.6 h ( 2 to 12 h). The mean treatment time of was 10 months (4 to 19 months). RESULTS: One hundred and forty-one patients were primarily healed, 97 patients were sutured at stage II. Split-thick skin grafting was performed at stage II was performed in 103 patients; free flap transplantation was performed in 25 patients. Three of the 34 patients with infection were removed steel plate; Eviscerate flap coverage wound was performed in 14 patients caused by the first metatarsal bone exposure; Toe amputation were performed in 22 cases caused by toes necrosis. Tarsometatarasl joints perforators' surgery was performed in 10 patients with forefeet necrosis. Thirty hundred and six patients were followed up from 3 to 20 months (averaged 10 months). The wounds healed well. CONCLUSION: VSD for soft tissue defects caused by ankle injury is a simple and effective method, but can not replace debridement and transfer flap.