Objective The aim of this study was to compare the clinical and radiographic outcomes of clavicular hook plate fixation with and without coracoclavicular (CC) tape augmentation for the treatment of acute unstable AC dislocation. Methods We treated 47 patients (31 men and 16 women; mean age: 47 years (range, 21–81)) with unstable acute AC dislocations (Rockwood III–V) and divided them into two groups according to the treatment modality, with hook plate fixation (hook plate group) or hook plate plus CC tape augmentation (combined group). We assessed radiologic findings, such as subacromial osteolysis and AC osteoarthritis. We also evaluated the clinical outcomes using a visual analogue scale (VAS) for pain, as well as the University of California at Los Angeles (UCLA) Shoulder Rating Scale and the American Shoulder and Elbow Surgeons (ASES) Shoulder Score. Results We found that the combined group had less subacromial osteolysis upon radiography, although the CC distance was similar in both groups (119 ± 29.7% of contralateral side CC distance in hook plate group versus 119 ± 34.8% in the combined group, p = 0.77). Compared with the hook plate group, the combined group had a lower VAS score (4.5 ± 2.3 in hook plate group versus 2.3 ± 1.4 in the combined group, p < 0.001), better UCLA scores (19.9 ± 4.9 in hook plate group versus 27.2 ± 4.0 in the combined group, p < 0.001) as well as better ASES scores (51.9 ± 17.8 in hook plate group versus 73.8 ± 13.1 in the combined group, p < 0.001) at 3 and 6 months after surgery. Conclusion Hook plate fixation plus CC tape augmentation may prevent subacromial osteolysis and yield better short-term functional outcomes. Level of Evidence Level III, Therapeutic Study.

To maintain the corrected alignment after high tibial osteotomy (HTO), fixation with titanium locking plate and screws is widely used in current practice; however, screw breakage is a common complication. Thus, this study was to investigate the mechanical stability of HTO with locking plate and various screw fixations, including the length as well as the type. A finite element (FE) model involving a distal femur, meniscus, and a proximal tibia with HTO fixed with a titanium locking plate and screws was created. The angle of the medial open wedge was 12°, and bone graft was not used. Two types of screws, namely conventional locking and far-cortical locking screws, with various lengths and configurations were used. At the proximal tibia, conventional locking screws with different lengths, 30 and 55 mm, were used; at the tibia shaft, different screw fixations including one-cortical, two-cortical, and far-cortical locking screws were used. The use of far-cortical locking screw generated the highest equivalent stress on the screws, which was four times (from 137.3 to 541 MPa) higher than that of the one-cortical screw. Also, it led to the maximum deformation of the tibia and a greater gap deformation at the osteotomy site, which was twice (from 0.222 to 0.442 mm) larger than that of the one-cortical screw. The effect of different locking screw length on tibia deformation and implant stress was minor. Thus, far-cortical locking screws and plates increase interfragmentary movement but the screw stress is relatively high. Increasing the protection time (partial weight duration) is suggested to decrease the risk of screw breakage in HTO through fixation with titanium far-cortical locking screws and plates.

Cannulated screws with an anterior wire are currently used for managing transverse patellar fracture. However, the addition of anterior wiring with various types of screws via open surgery to increase the mechanical stability is yet to be determined. Hence, this study aimed to compare the mechanical behaviors of a fractured patella fixed with various screws types and at various screw locations with and without the anterior wire. The present study hypothesized that using the anterior wire reduces the fracture gap formation. A finite element (FE) model containing a fractured patella fixed with various types of cannulated screws and anterior wiring was created in this study. Three types of screws, namely partial thread, full thread, and headless compression screws, and two screw depths, namely 5 and 10 mm away from the anterior surface of the patella, were included. The effect of the anterior wire was clarified by comparing the results of surgical fixation with and without the wire. Two magnitudes and two loading directions were used to simulate and examine the mechanical responses of the fractured patella with various fixation conditions during knee flexion/extension. Compared with partial thread and headless compression screws, the full thread screw increased the stability of the fractured patella by reducing fragment displacement, fracture gap formation, and contact pressure while increasing the contact area at the fracture site. Under 400-N in the direction 45°, the full thread screw with 5-mm placement reduced the gap formation by 86.7% (from 2.71 to 0.36 mm) and 55.6% (from 0. 81 to 0. 36 mm) compared with the partial thread screw with 10-mm placement, respectively without and with the anterior wire. The anterior wire along with the full thread screw is preferentially recommended for maintaining the surgical fixation of the fractured patella. Without the use of anterior wiring, the full thread screw with 5-mm placement may be considered as a less invasive alternative; however, simple screw fixation at a deeper placement (10 mm) is least recommended for the fixation of transverse patellar fracture.