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Abstract Introduction Platelet-rich plasma (PRP) is a fraction of plasma in which several growth factors are concentrated at high levels. The active soluble releasate isolated following platelet activation of PRP (PRP-releasate) has been demonstrated to stimulate the metabolism of IVD cells in vitro. The in vivo effect of PRP-releasate on degenerated IVD remains unknown. The purpose of this study was to determine the reparative effects of autologous PRP-releasate on degenerated intervertebral discs (IVDs). Methods To induce disc degeneration, New Zealand white rabbits (n = 12) received anular puncture in two noncontiguous discs. Autologous PRP and PPP (platelet-poor plasma) were isolated from fresh blood using two centrifugation techniques. Four weeks after the initial puncture, releasate isolated from clotted PPP or PRP (PPP- or PRP-releasate), or phosphate-buffered saline (PBS; control) was injected into the punctured discs. Disc height, magnetic resonance imaging (MRI) T2-mapping and histology were assessed. Results Anular puncture produced a consistent disc narrowing within four weeks. PRP-releasate induced a statistically significant restoration of disc height (PRP vs. PPP and PBS, P

Abstract Background Malignant soft tissue tumors of the foot are extremely rare and thus can be prematurely excised without appropriate preoperative evaluation. The present study compares adverse effects between unplanned and planned surgical excisions. Methods We retrospectively reviewed the clinical records, radiographs, pathology reports and pathological specimens of 14 consecutive patients with soft tissue sarcoma of the foot among 592 with sarcomas between 1973 and 2009. We then compared the incidence and clinical outcomes after unplanned (UT; n = 5) and planned (PT; n = 9) surgical excisions of foot sarcomas. Results The most frequent diagnosis was synovial sarcoma (n = 4; 28.6%). The overall 5-year survival rates of the PT and UT groups were 65.6% and 60.0%, respectively, and the event-free 5-year survival rates were 63.5% and 40.0%, respectively. Event-free and overall survival rates did not significantly differ between the two groups. However, tumors were significantly larger in the PT group than in the UT group (p < 0.05). Conclusions Unplanned resection lead to a relatively worse prognosis and a likelihood of recurrence despite additional resections. We recommend that soft tumors of the foot should only be excised after appropriate preoperative evaluation regardless of the size of the tumor.

Abstract Background Leptomeningeal carcinomatosis occurs in patients with cancer at the rate of approximately 5%; it develops particularly in patients with breast cancer, lung cancer, melanoma, leukemia, or malignant lymphoma. We describe a rare case of leptomeningeal carcinomatosis in which spinal intradural squamous cell carcinoma with no lesions in the cerebral meninges and leptomeninx, was the primary lesion. Methods A 64-year-old man complained of sacral pain. Although the patient was treated with analgesics, epidural block and nerve root block, sacral pain persisted. Since acute urinary retention occurred, he was operated on. The patient was diagnosed as having an intradural squamous cell carcinoma of unknown origin. Results Since the patient presented with a slightly decreased level of consciousness 2 months after surgery, he was subjected to MRI scanning of the brain and spinal cord, which revealed disseminated lesions in the medulla oblongata. The patient died of pneumonia and sepsis caused by methicillin-resistant Staphylococcus aureus 5 months after surgery. Conclusion We report the first case of a patient with intradural squamous cell carcinoma with unknown origin that developed independently in the sacrum.

Abstract Background X-ray images of lumbar degenerative diseases often show not only claw osteophytes, but also pairs of osteophytes that form in a direction away from the adjacent disc. We have investigated the direction of the formation of anterior lumbar vertebral osteophytes across the lumbar vertebrae using a sufficient number of lumbar radiographs, because osteophytes images can provide essential information that will contribute to the understanding of the pathology and progress of lumbar spine degeneration. Methods The direction of the formation of 14,250 pairs of anterior lumbar vertebral osteophytes across the adjacent intervertebral discs in 2,850 patients who were all over 60 years old was investigated. Anterior lumbar vertebral osteophytes were distributed into six groups based on the direction of extension of each pair of osteophytes across the intervertebral disc space. Results In L1–L2 and L2–L3, the number of patients classified into groups B (the pair of osteophytes extended in the direction of the adjacent disc) and C (almost complete bone bridge formation by a pair of osteophytes across the intervertebral disc space) was larger than that classified into group D (the pair of osteophytes extended in a direction away from the adjacent disc). In L3–L4, L4–L5 and L5-S1, the number of patients in group D was greater than that of patients belonging to groups B and C. Conclusion Our study showed that pairs of osteophytes frequently formed in the direction of the adjacent disc in the upper lumbar vertebrae (L1–L2 and L2–L3) and in the direction away from the adjacent disc in middle or lower lumbar vertebrae (L3–L4, L4–L5, and L5-S1).

Abstract Background There have been reports of serious complications associated with pedicle screw fixation, including nerve root injuries caused by accidental screw insertion. We have developed a new system of lumbar spinal instrumentation that we call Tadpole system®. The purposes of this report were to show the results of a biomechanical study and the short-term outcome of a clinical study, as well as to determine the usefulness of this system. Methods The Tadpole system® lumbar spinal fusion is a hook-and-rod system according to which the spine is stabilized using 2 sets of 2 spinous processes each that are held in place by 4 hooks tandemly connected to a rod. The biomechanical study was done using 5 human lumbar cadaveric spines, and the range of motion (ROM) was examined in a non-treatment model, an injured model, a pedicle screw fixation model and a Tadpole system® model. For the short-term clinical study the Tadpole system® was used in 31 patients, and the factors analyzed were operation time, time required for spinal instrumentation, amount of intraoperative bleeding, postoperative improvement rate of the Japanese Orthopaedic Association (JOA) score for lumbar spinal disorders, instrumentation failure, spinous process fracture, spinal fluid leakage, nerve root injury, postoperative infection, and bone fusion 2 years after the operation. Results The ROM in the Tadpole system® model was slightly bigger than that in the pedicle screw fixation model, but smaller than that in the normal control model. These biomechanical data indicated that the Tadpole system® provided fairly good stability. The mean operation time was 79 min, the mean time required for spinal instrumentation was 8 min, and the mean amount of intraoperative bleeding was 340 mL. The mean postoperative improvement rate of JOA score was 70.9 ± 24.8%. Instrumentation failure (dislocation of a hook) occurred in one patient, and none of the patients developed spinous process fracture, spinal fluid leakage, nerve root injury, or postoperative infection. Two years after the operation, bone union was confirmed in 29 of the 31 patients (93.5%). Conclusion We conclude that this system is a useful, easy-to-use and safe spinal instrumentation technique for lumbar fusion surgery.