Comminuted proximal humerus fractures are often repaired by metal plates, but potentially still experience bone refracture, bone \"stress shielding,\" screw perforation, delayed healing, and so forth. This \"proof of principle\" investigation is the initial step towards the design of a new plate using alternative materials to address some of these problems. Finite element modeling was used to create design graphs for bone stress, plate stress, screw stress, and interfragmentary motion via three different fixations (no, 1, or 2 \"kickstand\" [KS] screws across the fracture) using a wide range of plate elastic moduli (EP = 5-200 GPa). Well-known design optimization criteria were used that could minimize bone, plate, and screw failure (i.e., peak stress < ultimate tensile strength), reduce bone \"stress shielding\" (i.e., bone stress under the new plate ≥ bone stress for an intact humerus, titanium plate, and/or steel plate \"control\"), and encourage callus growth leading to early healing (i.e., 0.2 mm ≤ axial interfragmentary motion ≤ 1 mm; shear/axial interfragmentary motion ratio <1.6). The findings suggest that a potentially optimal configuration involves the new plate being manufactured from a material with an EP of 5-41.5 GPa with 1 KS screw; but, using no KS screws would cause immediate bone fracture and 2 KS screws would almost certainly lead to delayed healing. A prototype plate might be fabricated using alternative materials suggested for orthopedics and other industries, like fiber-metal laminates, fiber-reinforced polymers, metal foams, pure polymers, shape memory alloys, or 3D-printed porous metals.

BACKGROUND: This study\'s purpose was to evaluate the biomechanical performance of plate-nail and dual-plate fixation for the treatment of AO/OTA 41-C2 tibial plateau fractures.
METHODS: Twenty synthetic tibias were selected and randomly divided into a plate-nail group (n = 10) and a dual-plate group (n = 10). After the artificial tibias were osteotomized to simulate AO/OTA 41-C2 tibial plateau fractures in both groups, the plate-nail and the dual-plate methods, respectively, were used for fixation, and then axial compression loading, three-point bending, torsion, and axial failure tests were carried out. The data of each group were recorded and statistically analyzed.
RESULTS: In the axial compression test, the average stiffness of the plate-nail group was higher than that of the dual-plate group (p < 0.05). The displacement generated in the plate-nail group was significantly smaller than that in the dual-plate group (p < 0.05). In the resisting varus test, the stress of the plate-nail group was significantly higher than that of the dual-plate group (p < 0.05). In the resisting valgus test, the stress of the plate-nail group was slightly higher than that of the dual-plate group, but the difference was not statistically significant (p > 0.05). In the static torsion test, the load applied to the plate-nail group was smaller than that of the dual-plate group when rotated to 5° (p < 0.05). In the axial compression failure test, the average ultimate load of the plate-nail group was significantly higher than that of the dual-plate group (p < 0.05).
CONCLUSIONS: The treatment of AO/OTA 41-C2 tibial plateau fractures with plate-nail fixation is superior to that with dual-plate fixation in resisting axial stress and preventing tibial varus deformity, while dual-plate fixation has better resisting torsional ability.

UNASSIGNED: To compare the effectiveness of open reduction and hook plate fixation versus closed indirect reduction and dorsal extension blocking Kirschner wire fixation for bony mallet fingers.
UNASSIGNED: The clinical data of 68 patients with bony mallet finger who admitted between May 2019 and June 2022 were retrospectively analyzed. Among them, 33 cases were in the open group (treated with open reduction and hook plate fixation) and 35 cases were in the closed group (treated with closed indirect reduction and dorsal extension blocking Kirschner wire fixation). There was no significant difference between the two groups in terms of gender, age, the affected side, the affected finger, cause of injury, time from injury to operation, and Wehbé-Schneider classification ( P>0.05). The operation time, intraoperative fluoroscopy frequency, fracture healing time, time of returning to work, and postoperative complications were recorded and compared between the two groups. At 12 months after operation, visual analogue scale (VAS) score was used to assess the pain of the injured finger, active flexion range of motion and extension deficit of the distal interphalangeal joint (DIP) were measured by goniometer, and the effectiveness was assessed by Crawford criteria.
UNASSIGNED: All patients in the two groups were followed up 12-26 months, with an average of 15 months. There was no significant difference in the follow-up time between the closed group and the open group ( P>0.05). The operation time in the closed group was shorter than that in the open group, and the intraoperative fluoroscopy times, the fracture healing time, and the time of returning to work in the closed group were more than those in the open group, and the differences were significant ( P<0.05). In the closed group, there were 5 cases of pinning tract infection and 3 cases of small area pressure ulcer skin necrosis on the dorsal side of the finger, which were cured after intensive nursing and dressing change. Local nail depression deformity occurred in 7 cases in the open group, and the deformity disappeared after removal of plate. The incisions of the other patients healed uneventfully without complications such as infection, skin necrosis, exposure of the internal fixation, or nail deformity. There was no significant difference in the incidence of skin necrosis between the two groups ( P>0.05), but the differences in the incidence of infection and nail deformity between the two groups were significant ( P<0.05). There was no significant difference in VAS score, DIP active flexion range of motion, DIP extension deficiency, or Crawford criteria evaluation between the two groups at 12 months after operation ( P>0.05). At last follow-up, there was no DIP osteoarthritis and joint degeneration in both groups.
UNASSIGNED: Open reduction and hook plate fixation versus closed indirect reduction and dorsal extension blocking Kirschner wire fixation have their own advantages and disadvantages, but both of them have good results in the treatment of bony mallet fingers. Open reduction and hook plate fixation is recommended for young patients with bony mallet fingers who are eager to return to work.
UNASSIGNED: 比较切开复位钩状钢板固定与闭合间接复位背侧伸直阻挡克氏针固定治疗骨性锤状指的临床疗效。.
UNASSIGNED: 回顾分析 2019年5月—2022年6月收治且符合选择标准的68例骨性锤状指患者临床资料。其中切开组33例（采用切开复位钩状钢板固定），闭合组35例（采用闭合间接复位背侧伸直阻挡克氏针固定治疗）。两组患者性别、年龄、患侧侧别、伤指指别、致伤原因、受伤至手术时间及Wehbé-Schneider分型比较差异均无统计学意义（ P>0.05）。记录并比较两组患者手术时间、术中透视次数、骨折愈合时间、返岗工作时间及并发症发生情况；术后12个月采用疼痛视觉模拟评分（VAS）评定伤指疼痛情况，量角器测量手指远侧指间关节（distal interphalangeal joint，DIP）主动屈曲活动度及伸直欠缺度，采用Crawford标准评定临床疗效。.
UNASSIGNED: 两组患者均获随访，随访时间12～26个月，平均15个月；闭合组和切开组随访时间比较差异无统计学意义（ P>0.05）。闭合组手术时间短于切开组，术中透视次数、骨折愈合时间及返岗工作时间均多于切开组，差异均有统计学意义（ P<0.05）。闭合组发生针道感染5例、末节指背侧皮肤小面积压疮坏死3例，经加强护理换药后痊愈；切开组发生7例指甲局部凹陷畸形，拆除内固定钢板后畸形消失；其余患者切口均顺利愈合，无感染、皮肤坏死、内固定物外露、指甲畸形等并发症发生。两组患者皮肤坏死发生率比较差异无统计学意义（ P>0.05），感染和指甲畸形发生率比较差异有统计学意义（ P<0.05）。术后12个月，两组VAS评分、DIP主动屈曲活动度、DIP伸直欠缺度及Crawford标准评价比较差异均无统计学意义（ P>0.05）。 末次随访时两组患者均无DIP骨关节炎及关节退行性改变发生。.
UNASSIGNED: 切开复位钩状钢板固定与闭合间接复位背侧伸直阻挡克氏针固定治疗骨性锤状指虽各有利弊，但均取得了较好治疗效果；对于急于重返工作岗位的年轻骨性锤状指患者建议采用切开复位钩状钢板固定。.

BACKGROUND: Titanium implants are commonly used for surgical fixation in orthopedic trauma, and have many benefits compared to stainless steel implants. Despite these benefits, some orthopedic surgeons remain hesitant to use titanium implants due to concerns of difficulty with future implant removal, given concerns with cold-welding and screw strippage. The objective of this study was to assess difficulties associated with titanium plate and screw implant removal.
METHODS: This is a retrospective case series from a large hospital system. Patients were identified using Current Procedural Terminology (CPT) code 20,680 from 2017 to 2020. Patients were included if they had removal of titanium plate and screws from the upper or lower extremity, were at least18 years of age, and considered skeletally mature. The ease of titanium plate/screw removal was determined by assessing for implant cold-welding, broken screws, stripped screws, and the need for advanced tools (screw removal set, trephine, burr).
RESULTS: 157 patients were identified, with a mean age of 54 years and 59 % female. In total 1274 screws were removed: 14 (1.1 %) were stripped, 8 (0.6 %) were cold-welded, 42 (3.3 %) were loose, and 13 (1.0 %) were broken. 183 plates were removed in total, and 15 (8.2 %) had bone overgrowth that required removal. 12 (7.6 %) procedures were complicated and required the use of advanced tools. Complicated implant removal operations occurred after significantly longer in vivo implant time (mean of 3.7 vs. 1.1 years, p = 0.036), were associated with a younger age, were more likely to occur in lower extremity procedures (p = 0.034), and took significantly longer time for removal (95 vs. 42 min, p < 0.001).
CONCLUSIONS: Despite concerns with titanium implants, we found a low rate of screw strippage, breakage, and cold welding during the removal process. However, 7.6 % of the 157 surgeries required additional tools other than just a screwdriver, and needed additional operative time. This information allows treating surgeons to plan for implant removal when titanium implants have been used for fixation.
METHODS: IV.

UNASSIGNED: This study aims to analyze the biomechanical characteristics of posterolateral plateau fractures fixed by a novel anatomical plate using finite element analysis.
UNASSIGNED: A three-dimensional digital model of the full length of right tibiofibula was obtained by CT scanning. A posterolateral tibial plateau fracture model was then created. The acquired fracture model was assembled with 4 groups of internal fixations: Group A, novel anatomical plate; Group B, straight buttress plate; Group C, oblique T-shaped locking plate; Group D, two lag screws. Axial loads of 500, 1,000 and 1,500 N perpendicular to the horizontal plane were used to simulate the stress on the lateral plateau of a 65 kg person standing, walking and fast running.
UNASSIGNED: Vertical displacements of the posterolateral fragments in each of the four groups gradually increased under loads from 500 N to 1,500 N. The maximum displacement of the fracture fragment in four groups were all located on the lateral side of the proximal part, and the displacement gradually decreased from the proximal part to the distal end. The maximum displacement values under the axial load of 1,500 N was in the following order: novel anatomical plate (1.2365 mm) < oblique T-shaped locking plate (1.314 mm) < two lag screws (1.3747 mm) < straight buttress plate (1.3932 mm). As the axial load increased, the stress value of the different internal fixation models gradually increased. The stress behavior of the same internal fixation model under different loads was similar. The maximum stress value under the axial load of 1,500 N was in the following order: novel anatomical plate (114.63 MPa) < oblique T-shaped locking plate (277.17 MPa) < two lag screws (236.75 MPa) < straight buttress plate (136.2 MPa).
UNASSIGNED: The patients with posterolateral plateau fractures fixed with a novel anatomical plate in standing, walking and fast running can achieve satisfactory biomechanical results, which lays the foundation for future applications. At the same time, clinical fracture types are often diverse and accompanied by damage to the soft tissue. Therefore, the ideal surgical approach and appropriate internal fixation must be selected based on the patient\'s injury condition.

BACKGROUND: Treatment for complex olecranon fractures with metaphyseal comminution can be challenging. To improve reduction maneuvers and augment stability, we apply a small medial and/or lateral locking compression plate (LCP) prior to placing a posterior contoured 3.5 mm-2.7 mm LCP. The aim is to describe our technique and outcomes of this \"orthogonal\" plating technique.
METHODS: 26 patients were treated with orthogonal plating. Clinical outcome variables were available for all patients at a median of 27 months (IQR 6-54), and patient-reported outcomes (Q-DASH and MEPS) for 23 patients at 38 months (IQR 18-71).
RESULTS: All fractures healed at a median of 2.0 months (IQR 1.5-3.8). The median elbow flexion was 120°, extension-deficit 15°, pronation 88°, and supination 85°. The median Q-DASH was 9 (IQR 0-22) and the median MEPS was 90 (IQR 80-100). Hardware was electively removed in seven patients. One patient had a late superficial infection that resolved with hardware removal and antibiotics, and one patient had two consecutive re-fractures after two hardware removals; and healed after the second revision surgery.
CONCLUSIONS: Orthogonal plating with a posterior LCP and a small medial and/or lateral LCP is a safe technique that leads to excellent healing rates, and good clinical and patient-reported outcomes.

OBJECTIVE: To compare the biomechanical properties of adjunctive dorsal spanning plate (DSP) fixation with traditional K-wire fixation of perilunate dislocations in a cadaveric model.
METHODS: Fourteen fresh-frozen cadaveric wrists underwent simulated perilunate injury. The specimens were randomly allocated to either K-wire fixation versus K-wire and DSP fixation. Scapholunate (SL) ligament repair was performed in all specimens. The constructs were tested using a robot cyclically and to failure. Fluoroscopic images were obtained of the specimens prior to simulated injury, after fixation, after 10 and 100 loading cycles, and at construct failure. Differences in carpal alignment parameters (SL interval, SL angle, lunotriquetral interval, and capitolunate angle) and load to failure were recorded.
RESULTS: There were no statistically significant differences between the two group\'s carpal alignment parameters after fixation. Specimens fixated with K-wires and DSP required significantly higher loads to achieve construct failure. The only significant difference between the two groups\' carpal alignment parameters was SL interval change at failure.
CONCLUSIONS: Compared with K-wire fixation alone, adjunctive DSP fixation resulted in significantly increased loads to failure and decreased change in SL interval at the time of failure.
CONCLUSIONS: Adjunctive DSP may be a useful technique in the polytraumatized patient in whom providing back a weight-bearing extremity may be advantageous in the rehabilitation process.

UNASSIGNED: Acetabular fractures are among the most challenging injuries in traumatology. The complex anatomy usually requires extensive surgical approaches baring the risk for iatrogenic damage to surrounding neurovascular structures. As a viable alternative, minimally invasive endoscopic techniques have emerged during the recent years. This paper reports on the feasibility of different coupling mechanisms for a novel suprapectineal plate especially designed for minimally invasive acetabular surgery.
UNASSIGNED: A total number of 34 participants contributed to the present study, who differed in their arthroscopic and surgical experience. A laparoscopic model was used to compare four different coupling mechanisms by the number of failed attempts, the time required for plate fixation, the influence of surgical experience as well as the learning success for each individual coupling mechanism. Moreover, the feasibility of each mechanism was evaluated by a questionnaire.
UNASSIGNED: The results demonstrate that plates employing grooved and pressure-sliding coupling mechanisms exhibit fewer failed attempts and reduce trial times, especially in contrast to sole sliding mechanisms. Furthermore, our study revealed that proficiency in endoscopic procedures significantly influenced the outcome. Notably, the subjective evaluation of the participants show that the pressure base and pressure-slide base plate designs are the most supportive and feasible designs.
UNASSIGNED: In summary, the present study evaluates for the first-time different plate and coupling designs for minimal-invasive surgery, indicating a superior feasibility for plates with a grooved and pressure-sliding mechanism.

BACKGROUND: The association of ipsilateral tibia fractures has a low incidence, being up to 3.2% of total tibia fractures. Currently there is no gold standard regarding the ideal surgical treatment. The objective of this study is to analyze the surgical treatment and the radiographic and functional results, as well as the associated complication rate of ipsilateral bifocal tibia fractures.
METHODS: Retrospective observational study in our hospital from 2010 to 2022 of 24 patients who underwent bifocal fracture of the ipsilateral tibia. Demographic and surgical data and complications during follow-up were included.
RESULTS: The 24 patients were classified into group 1 when they presented a fracture of the plateau and distal tibia (25%), group 2 with a fracture of the plateau and diaphysis (33%) and group 3 with a fracture of the diaphysis and distal tibia (42%). 3 patients underwent surgery with 1 implant and 21 patients with 2 implants. The average follow-up time in outpatient clinics was 2 and a half years. At one year, 22 patients (92%) had full weight bearing and 2 patients had partial weight bearing (8%) due to the sequelae of the fractures. The average time for consolidation of the diaphysis was 7.75±2 months, with no significant differences observed between group 2 and group 3 (p=0.06). The average time for consolidation of the metaphysis was 3.50±1.5 months, with no significant differences observed between group 1 and group 2 (p=0.065). 7 patients (30%) had complications during follow-up.
CONCLUSIONS: Bifocal tibia fractures can be treated using a combination of intramedullary nailing and plate osteosynthesis with good long-term results, obtaining an optimal union rate and low complications. In addition, it facilitates the reduction of the fracture, thus facilitating the patient\'s recovery and obtaining good long-term functional results.

BACKGROUND: Avulsion fractures of the calcaneal tuberosity with significant displacement can cause soft tissue complications in the heel. However, a treatment strategy for calcaneal tuberosity fractures with poor heel-skin condition is yet to be established. Here, we report a case involving avulsion fracture of the calcaneal tuberosity presenting with superficial skin necrosis that was treated with a plate lacking the anterior component and screws inserted percutaneously.
METHODS: A 74-year-old woman presented with progressive right heel pain following an injury to her heel sustained approximately six weeks previously. She had experienced difficulty walking due to heel pain and superficial necrosis was observed on the posterior surface of the heel. Radiography and computed tomography revealed an avulsion fracture of the calcaneal tuberosity with superior displacement. Open reduction was performed using a lateral L-shaped incision. After inserting two cancellous screws percutaneously into the calcaneal tuberosity, we fixed a plate lacking the anterior component to the lateral surface of the calcaneus. The superficial necrosis healed gradually post-operatively. Bone union was confirmed using radiography six months post-operatively.
CONCLUSIONS: We developed a novel surgical procedure to treat avulsion fractures of the calcaneal tuberosity with poor skin condition. The combination of a plate lacking the anterior component and the percutaneous insertion of canulated cancellous screws can reduce the risk of post-operative soft tissue complications while maintaining fixation of the fractured fragment.
CONCLUSIONS: Our findings provide a novel surgical method for the treatment of avulsion fractures of the calcaneal tuberosity with soft tissue complications.