Liangqi Kang

Artificial disk replacement combined with midlevel ACDF versus multilevel fusion for cervical disk disease involving 3 levels.

The optimal surgical approach for cervical disk disease remains a matter of debate, especially for multilevel disease. The purpose of this study was to compare the results of 2 surgical strategies for cervical disk disease involving 3 levels: hybrid constructs, artificial disk replacement combined with midlevel anterior cervical diskectomy and fusion (ACDF), and 3-level ACDF. The authors prospectively compared patients who had cervical disk disease involving 3 levels that was treated with hybrid constructs or with 3-level ACDF. Patients were asked to use the Neck Disability Index (NDI) to grade their pain intensity preoperatively and at routine postoperative intervals of 1, 3, 6, 12, and 24 months. Dynamic flexion and extension lateral cervical radiographs were obtained while in the standing position preoperatively and at the postoperative intervals. The angular range of motion for C2-C7 and the adjacent segments was measured using the Cobb method. Twenty-four patients were treated, 12 with hybrid constructs and 12 with 3-level ACDF. Both groups had significant postoperative improvement in NDI scores and neck pain (P<.05). However, no significant difference was found between the groups (P>.05). The hybrid constructs group showed faster recovery of C2-C7 range of motion. Mean C2-C7 range of motion of the hybrid constructs group recovered to that of the preoperative value, but that of the 3-level ACDF group did not (P<.05). Range of motion of the superior and inferior adjacent segments showed significant differences between the 2 groups at 12 and 24 months postoperatively (P<.05). These findings suggest that the hybrid constructs is a safe and effective alternative for cervical disk disease involving 3 levels. The definite stabilization and maintained range of motion can be achieved right away, which can ensure a good preliminary clinical outcome.

Anterior versus posterior approach for four-level cervical spondylotic myelopathy.

The purpose of this study was to compare the results of 2 surgical strategies for 4-level cervical spondylotic myelopathy: a hybrid procedure using anterior cervical diskectomy and fusion (ACDF) combined with segmental corpectomy versus posterior laminectomy and fixation. Between 2002 and 2010, fifty-one patients with consecutive 4-level cervical spondylotic myelopathy were treated surgically, with 27 patients undergoing the hybrid procedure and 24 undergoing posterior laminectomy and fixation. Radiologic data were compared between the 2 groups, including cervical curvature and cervical range of motion (ROM) in the sagittal plane. Pre- and postoperative neurological status was evaluated using the Japanese Orthopaedic Association (JOA) scoring system and the Nurick grading system. Mean ROM at last follow-up was not significantly different between the 2 groups (P>.05). In the hybrid group, mean JOA score and Nurick grade improved from 9.6±1.4 and 2.74±0.45 respectively, preoperatively, to 13.9±1.3 and 0.86±0.38 respectively, postoperatively. In the fixation group, mean JOA score and Nurick grade improved from 9.4±1.2 and 2.81±0.42 respectively, preoperatively, to 13.1±1.5 and 1.32±0.36 respectively, postoperatively. The JOA scores and Nurick grades at last follow-up were significantly different between the 2 groups (P<.05). In patients with preoperative cervical kyphosis, preoperative JOA score and Nurick grade were not significantly different between the 2 groups (P>.05); however, JOA scores and Nurick grades at last follow-up showed better improvement in the hybrid group than in the fixation group (P<.01). In patients with preoperative cervical lordosis, the preoperative and last follow-up JOA score and Nurick grade were not significantly different between the 2 groups (P>.05).

Silencing of Ether à go-go 1 by shRNA inhibits osteosarcoma growth and cell cycle progression.

Recently, a member of the voltage-dependent potassium channel (Kv) family, the Ether à go-go 1 (Eag1) channel was found to be necessary for cell proliferation, cycle progression and tumorigenesis. However, the therapeutic potential of the Eag1 channel in osteosarcoma remains elusive. In the present study, a recombinant adenovirus harboring shRNA against Eag1 was constructed to silence Eag1 expression in human osteosarcoma MG-63 cells. We observed that Eag1-shRNA inhibited the proliferation and colony formation of MG-63 cells due to the induction of G1 phase arrest. Moreover, in vivo experiments showed that Eag1-shRNA inhibited osteosarcoma growth in a xenograft nude mice model. In addition, selective inhibition of Eag1 significantly decreased the expression levels of cyclin D1 and E. Taken together, our data suggest that the Eag1 channel plays a crucial role in regulating the proliferation and cell cycle of osteosarcoma cells, and represents a new and effective therapeutic target for osteosarcoma.

Voltage-gated potassium channel Kv1.3 is highly expressed in human osteosarcoma and promotes osteosarcoma growth.

Deregulation of voltage-gated potassium channel subunit Kv1.3 has been reported in many tumors. Kv1.3 promotes tumorigenesis by enhancing cell proliferation while suppressing apoptosis. However, the expression and function of Kv1.3 in osteosarcoma are unknown. In the present study, we detected the expression of Kv1.3 in human osteosarcoma cells and tissues by RT-PCR, Western blot and immunohistochemistry. We further examined cell proliferation and apoptosis in osteosarcoma MG-63 cells and xenografts following knockdown of Kv1.3 by short hairpin RNA (shRNA). We found that Kv1.3 was upregulated in human osteosarcoma. Knockdown of Kv1.3 significantly suppressed cell proliferation and increased apoptosis as demonstrated by enhanced cleavage of poly (ADP-ribose) polymerase (PARP) and the activation of Caspase-3/7. Furthermore, adenovirus delivered shRNA targeting Kv1.3 significantly inhibited the growth of MG-63 xenografts. Taken together, our results suggest that Kv1.3 is a novel molecular target for osterosarcoma therapy.

A minimally invasive anterior approach to reduction and screw fixation of coronoid fractures

We investigated a minimally invasive anterior approach to reduce and fix coronoid fractures with a screw in eight consecutive patients and evaluated seven patients at a minimum of 1 year (mean, 78 weeks; range, 61–89 weeks). It was only possible to repair seven of eight coronoid fractures. The average time to radiographic healing was 12 weeks and all healed without the screw loosening, migration or breakage. Endoscopy permitted an excellent view of coronoid fractures, allowing anatomic fixation, and as it avoided extensive soft tissue dissection, this method preserved soft tissue attachments of small coronoid fragments. This method was safe and minimally invasive.

Potassium Channel Ether à go-go1 Is Aberrantly Expressed in Human Liposarcoma and Promotes Tumorigenesis

The ether à go-go1 (Eag1) channel is overexpressed in a variety of cancers. However, the expression and function of Eag1 in liposarcoma are poorly understood. In the present study, the mRNA expression of Eag1 in different adipose tissue samples was examined by real-time PCR. Then, the protein expression of Eag1 in 131 different adipose tissues from 109 patients was detected by immunohistochemistry. Next, the associations between Eag1 expression and clinicopathological features of liposarcoma were analyzed. In addition, the effects of Eag1 on liposarcoma cell proliferation and cycle were evaluated by CCK-8, colony formation, xenograft mouse model, and flow cytometry, respectively. Finally, the activation of p38 mitogen-activated protein kinase (MAPK) was detected by Western blot analysis to explain the detailed mechanisms of oncogenic potential of Eag1 in liposarcoma. It was found that Eag1 was aberrantly expressed in over 67% liposarcomas, with a higher frequency than in lipoma, hyperplasia, inflammation, and normal adipose tissues. However, Eag1 expression was not correlated with clinicopathological features of liposarcoma. Eag1 inhibitor imipramine or Eag1-shRNA significantly suppressed the proliferation of liposarcoma cells in vitro and in vivo, accompanying with accumulation of cells in the G1 phase. These results suggest that Eag1 plays an important role in regulating the proliferation and cell cycle of liposarcoma cells and might be a potential therapeutic target for liposarcoma.

Design and Biomechanical Properties of a New Reconstruction Device for Treating Thoracolumbar Burst Fractures

Implants currently used for reconstruction of a burst vertebral body are associated with complications, including subsidence, nonunion, and substantial intraoperative blood loss. A new reconstruction device, the U-Cage (Double Engine Medical Material Ltd, Xiamen, Fujian, China), was designed to minimize complications.Six intact adult cadaver thoracolumbar (T11-L3) spines were collected and scanned by dual-energy X-ray absorptiometry (DEXA). The stiffness of the burst spine was subsequently compared with its previous intact state during flexion/extension, lateral bending, and rotation, and then subjected to a cyclic test to predict cage subsidence and device loosening. Axial load was applied continuously until failure to test the peak load that the specimen could withstand during the cyclic test. The correlation of bone mineral density and peak load was also analyzed. The instrumented specimens were found to be equivalent to intact bone in all directions (P>.05), with the exception of left rotation (P<.05). All specimens could withstand the cyclic test, and no subsidence or loosening of the device was detected. Average peak load for the instrumented specimens was 4137.5 N, which correlated with the average bone mineral density (r=0.915; P=.011).Thoracolumbar burst fractures instrumented with a U-Cage and anterolateral D-rod fixation achieved a stiffness similar to that of intact spines. This procedure may avoid the subsidence of the cage in vivo and serve as a better option for treating thoracolumbar burst fractures.

Posteromedial Anatomical Plate for the Treatment of Distal Tibial Fractures with Anterior Soft Tissue Injury

The treatment of distal tibial fractures with anterior soft tissue injury is relatively difficult. The aim of this study was to explore the efficacy and safety of the posteromedial anatomical plate for such fractures. Between February 2006 and January 2009, twenty-six cases of distal tibial fracture with anterior soft tissue injury were treated with posteromedial anatomical plates designed by our traumatic orthopedic center. Of the 26 cases, 12 were open fractures (4 Gustilo-Anderson type I, 5 type II, 2 type IIIA, and 1 type IIIB), and 14 were closed fractures (3 Tscherne-Oestern type I, 9 type II, 2 type III). Operation time, intraoperative blood loss, fracture healing time, American Orthopaedic Foot and Ankle Society (AOFAS) ankle score, and complications were recorded to evaluate treatment effects.Mean operation time was 72.5 ± 15.8 minutes (range, 45-105 minutes) with a mean intraoperative blood loss volume of 86.4 ± 17.3 mL (range, 50-150 mL). All 26 patients had good postoperative fracture healing. Mean union time was 19.2 ± 4.4 weeks (range, 13-30 weeks). Average AOFAS ankle score was 87.3 ± 9.2 (range, 68-99). No malunion, nonunion, limb-shortening deformity, or neurovascular injury occurred. Our results suggest that the posteromedial anatomical plate for the treatment of distal tibial fractures with anterior soft tissue injury is effective and results in no severe complications.

Bone splint technique and plating application in adolescent high-energy comminuted fracture of distal femur with bone defects

Comminuted fracture of distal femur is a common lower limb injury from traffic accidents, especially from motor accidents. Routine dynamic condylar screw (DCS) or 95-degree condylar plate (CP) sometimes cannot solve the bone defect in the center of alignment and contralateral diaphysis for the reason of absent screw anchor point, especially for AO C2.2-2.3 types. Many authors recommended open reduction and fixation with less invasive stabilization system (LISS) as the treatment of choice, but there are still problems in fusion and alignment. In this study, we reported our experiences with the use of bone splint technique in the high-energy commimuted fracture of distal femur with central and medial bone defect in adolescents.

Early results of thoraco lumbar burst fracture treatment using selective corpectomy and rectangular cage reconstruction

Background: Subsidence and late fusion are commonly observed in anterior subtotal corpectomy and reconstruction for treating thoracolumbar burst fractures. The subsidence rate of this surgical method was reported from 19.6% to 75% in the literatures, which would cause treatment failure. Thus, an improvement of anterior surgery technique should be studied to reduce these complications. Materials and Methods: 130 patients of thoracolumbar burst fractures treated by minimal corpectomy, decompression and U cage, between January 2009 and December 2010 were included in this study. The hospital Ethical Committee approved the protocols. The American Spinal Injury Association (ASIA) scale, visual analog scales, and Oswestry Disability Index (ODI) scores were used for clinical evaluation. The local kyphosis angle, vertebral height (one level above the fractured vertebral to one level below), canal stenosis, and fusion status were used to assess radiological outcome. All complications and demographic data such as number of male/female patients, average age, mode of trauma, burst level involved, mean surgery time and blood lost were reported. Results: 120 patients were followed up for 24 months. Most patients had improvement of at least 1 ASIA grade, and all experienced pain reduction. The mean ODI score steadily decreased after the surgery (P < 0.01). Approximately, 83.3% of patients achieved solid fusion at 3 months and reached 98.3% at 6 months. The kyphosis angle and radiographic height were corrected significantly after the surgery and with a nonsignificant loss of correction at 24 months (P > 0.05). The average canal stenosis index was increased from 39% to 99% after surgery. No cage subsidence or implant failure was observed. Conclusions: The clinical outcomes described here suggest that the selective corpectomy and rectangular cage reconstruction can effectively promote solid fusion and eliminate complications related to subsidence or implant failure.