Jeung-Tak Suh

The management of brachymetatarsia

We treated 35 brachymetatarsal rays of 18 feet in 12 patients by one-stage lengthening with interpositional bone grafts or by gradual lengthening with callotasis combined with shortening of the adjacent metatarsals and phalanges. Definition of the two parabolas which connect the metatarsal heads and the tips of the toes, and recognition of three patterns of metatarsal length, were helpful guides in treatment. In total, 36 excisions of the phalanges and/or the metatarsals were undertaken. The mean shortening was 8 mm. The radiological results were satisfactory. The mean values were as follows: one-stage lengthening, length gain, 1.3 cm; healing index, 1.3 months/cm; percentage increase, 30%; gradual lengthening, length gain, 2.0 cm; healing index, 2.0 months/cm; percentage increase, 50%. Associated shortening of an adjacent bone can avoid the disadvantages of one-stage lengthening which may not achieve target length and can result in neurovascular complications. Reduction of the target length enables the surgeon to carry out one-stage instead of gradual lengthening. It also shortens the length of treatment in the group undergoing callotasis and improves cosmesis.

Synovial Hemangioma of the Knee

Synovial hemangioma of a knee joint has been reported as a rare cause of pain, hemarthrosis, and intermittent locking. This case report describes our experience in excising intra-articular hemangioma of the knee joint. Complete resection, after arthroscopic examination, was performed in a 59-year-old man. Six months after the surgery, no evidence of recurrence was seen.

Detection of Locking Bolt Loosening in the Stem-Condyle Junction of a Modular Femoral Stem in Revision Total Knee Arthroplasty

We report one case of loosening of the locking bolt in the stem-condyle junction of a constrained modular femoral component in revision total knee arthroplasty. Early detection of loosening of the locking bolt was possible using reconstructed view of computerized tomography scans before complete disengagement and radiographic loosening of the stemmed femoral component. When using the Total Condyle III femoral component with a stem extension, surgeons should keep in mind that stress concentration at the stem-condyle junction can result in failure of the locking bolt although it is rare and that loosening or disengagement of the locking bolt may be a sign of a loose stemmed femoral component.

Deoxypodophyllotoxin induces cytoprotective autophagy against apoptosis via inhibition of PI3K/AKT/mTOR pathway in osteosarcoma U2OS cells

BACKGROUND A natural compound deoxypodophyllotoxin (DPT) possesses potent anti-proliferative and anti-tumor properties on several cancer types. It triggers cell cycle arrest followed by apoptosis through various cellular processes. However, it is limited to the action mechanism of DPT-mediated cell death modes via apoptosis and autophagy. METHODS Cell viability assay, morphological changes, annexin-V/propidium iodide (PI) assay, reactive oxygen species (ROS), acridine orange staining, and Western blot analyses were evaluated. RESULTS We demonstrated that DPT induced both apoptosis and autophagy via production of mitochondrial reactive oxygen species (ROS). DPT suppressed the PI3K/AKT/mTOR signaling cascades to lead autophagy process, resulting from conversion of light chain 3-I (LC3-I) into LC3-II and acidic vesicular organelles (AVOs) formation. Even if DPT-induced ROS were occurred in both apoptosis and autophagy, inhibition of ROS generation enhanced cell viability. Otherwise, 3-methyladeine (3-MA) impeding on autophagy accelerated an apoptotic response caused by DPT. Therefore, these findings suggest that DPT triggers cytoprotective autophagy against cytotoxic apoptosis. CONCLUSION Autophagy is required for cell survival by inhibition of apoptosis through down-regulation of PI3K/AKT/mTOR pathway against DPT-induced apoptosis in U2OS cells.