Mohamed E Abdel-Wanis

Sohag University, Sawhāj, Sūhāj, Egypt

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Publications (25)56.71 Total impact

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    ABSTRACT: Thyroid carcinoma generally has a favorable prognosis, and patients rarely present with distant metastases. Authors of several studies have proposed piecemeal resection for spinal metastases in thyroid carcinoma; however, few have analyzed the impact of local curative surgery such as total en bloc spondylectomy (TES) for thyroid carcinoma. The purposes of the present study are to determine the strategy of surgical treatment for spinal metastases of thyroid carcinoma and to evaluate the surgical results of and the prognosis associated with TES. Twenty-four cases of spinal metastases were retrospectively reviewed. The patients included 16 women and 8 men, with a mean age of 60.7 years. Histological examination showed follicular carcinoma in 15 cases, papillary carcinoma in 8, and medullary carcinoma in 1. Total en bloc spondylectomy was performed in 10 cases; debulking surgery, such as piecemeal excision or eggshell curettage, was performed in 14. The average follow-up time was 55 months (12-180 months). Four patients had no evidence of disease, 8 were alive with the disease, and 12 had died of the disease. The overall survival rate from the time of surgery was 74% at 5 years. Patients with visceral metastases had a significant, higher risk of death. The survival rate of patients following TES was 90% at 5 years, which was higher than the rate in patients who underwent debulking surgery (63%). However, no significant difference was observed between the 2 types of surgery. There was a local recurrence after debulking surgery in 8 (57%) of 14 cases. Because of the recurrences, reoperation was required after a mean of 41 months. In contrast, there was a local recurrence after TES in only 1 (10%) of 10 cases. The difference between debulking surgery and TES regarding local recurrence was statistically significant. Total en bloc spondylectomy with enough of a margin provided favorable local control of spinal metastases of thyroid carcinoma during a patient's lifetime.
    Journal of neurosurgery. Spine 02/2011; 14(2):172-6. · 1.61 Impact Factor
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    ABSTRACT: Treatment of ventral lesions to the spinal cord in the thoracic spinal canal (e.g., meningiomas) are surgical challenges. Original or modified costotransversectomy has been commonly used for extirpation of such lesions. However, these techniques incur great loss of posterior elements followed by spinal instability that requires spinal fusion. The authors have developed a new surgical technique that combined the advantages of posterolateral exposures and recapping laminoplasty (recapping T-saw laminocostotransversoplasty). The purpose of this study was to examine the safety and effectiveness of this technique for surgical excision of ventrally located meningiomas in the thoracic region. Three patients underwent recapping laminocostotransversoplasty for extirpation of ventral meningiomas in the thoracic spine. A T-saw was used for bone cutting. Following tumor extirpation with the infiltrated dura and dural reconstruction, the resected posterior elements were recapped to their original sites. Patients were evaluated both clinically and radiographically by plain radiography and computed tomography (CT). Tumor excision, dural reconstruction, and bone recapping were achieved without neurological complications in all patients. Neurological improvement was observed dramatically in all three patients. A mean of 2.3 laminae and 1.3 ribs were excised. The mean follow-up was 9.7 years. CT scans confirmed primary bony union in all patients within 6 months. No major complications were reported. Recapping T-saw laminocostotransversoplasty not only provides greater access to the anterior thoracic spinal canal but also allows anatomical reconstruction of the excised bone.
    Journal of Orthopaedic Science 09/2009; 14(5):548-55. · 0.96 Impact Factor
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    M E Abdel-Wanis, N Kawahara, K Tomita
    International Orthopaedics 03/2008; 32(1):135-6; author reply 137. · 2.32 Impact Factor
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    ABSTRACT: We present a retrospective study of patients suffering from a variety of benign tumours in whom external fixators were used to treat deformity and limb-length discrepancy, and for the reconstruction of bone defects. A total of 43 limbs in 31 patients (12 male and 19 female) with a mean age of 14 years (2 to 54) were treated. The diagnosis was Ollier's disease in 12 limbs, fibrous dysplasia in 11, osteochondroma in eight, giant cell tumour in five, osteofibrous dysplasia in five and non-ossifying fibroma in two. The lesions were treated in the tibia in 19 limbs, in the femur in 16, and in the forearm in eight. The Ilizarov frame was used in 25 limbs, the Taylor Spatial Frame in seven, the Orthofix fixator in six, the Monotube in four and the Heidelberg fixator in one. The mean follow-up was 72 months (22 to 221). The mean external fixation period was 168 days (71 to 352). The mean external fixation index was 42 days/cm (22.2 to 102.0) in the 22 patients who required limb lengthening. The mean correction angle for those with angular deformity was 23 degrees (7 degrees to 45 degrees ). At final follow-up all patients had returned to normal activities. Four patients required a second operation for recurrent deformity of further limb lengthening. Local recurrence occurred in one patient, requiring further surgery.
    Journal of Bone and Joint Surgery - British Volume 09/2007; 89(8):1077-83. · 2.69 Impact Factor
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    Hiroyuki Tsuchiya, Mohamed E Abdel-Wanis, Katsuro Tomita
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    ABSTRACT: A new classification system for juxta-articular osteosarcoma around the knee joint was developed to allow biological reconstructions using distraction osteogenesis or frozen autograft containing tumors treated with liquid nitrogen. Type I: Tumor has metaphyseal extension to a maximum of 2 cm from the epiphyseal cartilage plate. Type II: Tumor extends to at least half the circumference of the epiphyseal cartilage plate. Type III: Extension to the whole circumference of the epiphyseal cartilage plate. Type IV: Tumor extends to part of the epiphysis through any point of the epiphyseal cartilage plate 10 mm from the joint line. Type V: Tumor extends to half or less of the epiphysis. Type VI: Extension of the tumor to more than half of the epiphysis. Twenty patients with juxta-articular osteosarcoma around the knee joint were treated according to this classification system. The cohort comprised 12 males and 8 females with a mean age of 20 years. The tumors were located in the femur in 12 patients and in the tibia in 8 patients. The tumors were Type II in 1 patient, Type III in 8 patients, Type IV in 2 patients, Type V in 3 patients and Type VI in 6 patients. Reconstruction after tumor excision was performed using distraction osteogenesis in 13 patients and using frozen autografts in 7 patients. The mean follow-up in the series was 54 months, ranging from 5 to 103 months. The classification system may act as a guide to appropriate decision-making in cases of juxta-articular osteosarcoma around the knee joint. Biological reconstruction, using distraction osteogenesis or frozen autografts, may yield good functional results without leading to an increase in the incidence of local recurrence.
    Anticancer research 01/2006; 26(1B):447-53. · 1.71 Impact Factor
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    ABSTRACT: Morphometric changes of the spinal cord and influence on spinal cord-evoked potentials and spinal cord blood flow and postoperative function of hind limbs were studied in various degrees of acute spinal column shortening in dogs. To study the morphometric and physiologic effects of acute spinal column shortening on the spinal cord. The technique of acute spinal column shortening is sometimes applied for correction of spinal deformity, total en bloc spondylectomy operation, or other diseases. However, safe limits and physiologic effects of acute spinal column shortening have not yet been described. Total spondylectomy of T13 was performed in dogs after spinal instrumentation placed 2 levels above and 2 levels below the spondylectomy level. Spinal column was gradually shortened until the lower endplate of T12 contacted the L1 upper endplate (maximum of 20 mm). When any morphologic change of the dural sac or the spinal cord was observed, the length of shortening was measured. Spinal cord-evoked potentials were recorded on the exposed dura mater following epidural stimulation at the C7 level in 8 dogs. Spinal cord blood flow was measured during shortening in 6 dogs. Hindlimb function was evaluated 2 weeks after operation in 10 dogs. No morphometric changes occurred in the dural sac and the spinal cord until shortening of 7.2 +/- 1.7 mm (n = 6). From 7.2 +/- 1.7 to 12.5 +/- 1.1 mm shortening, the dural sac was deformed, whereas the spinal cord maintained its shape. Shortening more than 12.5 +/- 1.1 mm buckled the dural sac, and the spinal cord kinked itself and was compressed by the buckled dura in its concave side (n = 6). No changes could be detected in spinal cord-evoked potentials in 5 or 10 mm of shortening. Spinal cord-evoked potential changes were recorded in the 2 of 6 dogs with 15 mm of shortening. At 20 mm of shortening, spinal cord-evoked potential abnormality was observed in 4 of 6 dogs. At shortening of 5, 10, 15, and 20 mm, spinal cord blood flow was 146 +/- 10%, 160 +/- 21%, 102 +/- 17%, and 93 +/- 7% of the control (29.2 +/- 7.9 mL/100 g/min, n = 6), respectively. All 3 dogs with 10 mm ofshortening had normal hindlimb function 2 weeks after operation. One of the 3 dogs with 15 mm of shortening had paraparesis. Three of the 4 dogs with 20 mm of shortening had also paraparesis after operation. Acute spinal column shortening can be characterized into 3 phases. Phase 1, safe range: occurred during shortening within one-third of the vertebral segment and is characterized by no deformity of the dural sac or the spinal cord. Phase 2, warning range: occurred during spinal shortening between one-third and two-thirds of the vertebral segment and is characterized by shrinking and buckling of the dural sac and no deformity of the spinal cord. Phase 3, dangerous range: occurred after shortening in excess of two-thirds of the vertebral segment and is characterized by spinal cord deformity and compression by the buckled dura. Spinal shortening within the safe range increases spinal cord blood flow.
    Spine 04/2005; 30(6):613-20. · 2.16 Impact Factor
  • M E Abdel-Wanis, N Kawahara
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    ABSTRACT: Bony abnormalities are common findings in cases of neurofibromatosis 1. We might hypothesize that neurofibromin, the protein encoded by the neurofibromatosis 1 gene, plays important roles in bone development. Loss of function of oligodendrocyte-myelin glycoprotein gene and increased activity of ras p21 might increase the level of c-fos proto-oncogene in bones with formation of fibrous dysplasia-like tissue. Also, increased ras p21 might disturb collagen I synthesis by osteoblasts. Moreover, increased ras activity might increase the mitogenic signals to the nucleus through mitogen-activated protein kinase (MAPK) and disturb the level of the transcription factor core-binding factor alpha(1) (Cbfa1). Abnormal fibrous tissue and neurofibromas formed at the site of pseudarthrosis might represent abnormal response of periosteal fibroblasts for injury, an effect simulating the response of skin fibroblasts in neurofibromatosis 1 to injury.
    Medical Hypotheses 05/2003; 60(4):459-62. · 1.18 Impact Factor
  • M E Abdel-Wanis, N Kawahara
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    ABSTRACT: Although frequently encountered, no available consensus about the association between skeletal abnormalities and skin pigmentation. Several syndromes are characterized by the presence of skin pigmentation in association with skeletal disorders like neurofibroamtosis 1, McCune-Albright Syndrome, Jaffe-Campanacci Syndrome and Jaffe-Lichtenstein Syndrome. Even in the absence of these syndromes, skeletal abnormalities were detected in all radiologically examined patients having patterned skin pigmentation. Although skin pigmentation is controlled by several factors, melatonin is the most reliable factor to have relation to development of skeletal abnormalities. Recent research works support that melatonin might play a role in bone development and several hypotheses link melatonin with some bone diseases associated with skin pigmentation. It seems that melatonin deficiency is a probable operating co-factor in a lot of clinical situations characterized by skin pigmentation and skeletal disorders. This would explain some of the un-explained observations related to these syndromes and research works along these lines might lead to the development of efficient treatment for these diseases.
    Medical Hypotheses 01/2003; 61(5-6):640-2. · 1.18 Impact Factor
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    ABSTRACT: In 11 patients juxta-articular osteosarcoma around the knee was treated by intraepiphyseal excision of the tumour and reconstruction of the bone defect by distraction osteogenesis. Preoperative and postoperative chemotherapy was given to eight patients with high-grade tumours. The articular cartilage of the epiphysis and a maximum of healthy soft tissues were preserved. Distraction osteogenesis was then carried out. The mean gain in length was 9.7 cm. Full function of the limb was preserved in all except one patient, with a mean follow-up of 53.8 months. Treatment of juxta-articular osteosarcomas around the knee with joint preservation and biological reconstruction using distraction osteogenesis can give excellent functional results.
    Journal of Bone and Joint Surgery - British Volume 12/2002; 84(8):1162-6. · 2.69 Impact Factor
  • M E Abdel-Wanis, H Tsuchiya
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    ABSTRACT: Fibrous dysplasia of bone might be monostotic, polystotic, or occurs as a part of McCune-Albright syndrome and Jaffe-Lichtenstein syndrome. Activating mutations of GNAS1 gene was identified in patients with fibrous dysplasia. However, fibrous dysplasia might occur in the absence of these mutations and fibrous dysplastic tissue was produced in vitro by the effects of excess exogenous cAMP on human osteogenic cells. It was proved that the fibrous dysplastic tissue is deficient in bone sialoprotein. Melatonin deficiency might be hypothesized in syndromes associated with fibrous dysplasia or formation of fibrous dysplasia-like tissue. The receptor RZR/ROR is the nuclear receptor of melatonin and the human bone sialoprotein gene contains a RZR/ROR response element. It was supposed that binding of melatonin to its membrane receptors results in changes in the levels of activity of nuclear cAMP that lead to alteration of expression of bone sialoprotein. Also, melatonin deficiency might increase cAMP in bone through its effect on prostaglandins of the E group. Further, melatonin deficiency might explain precocious puberty in cases of McCune-Albright syndrome. We might hypothesize that melatonin deficiency might play a role in development of fibrous dysplasia in some cases.
    Medical Hypotheses 12/2002; 59(5):552-4. · 1.18 Impact Factor
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    ABSTRACT: Deformity combined with shortening of 18 lower limb segments of 17 patients was treated with the Ilizarov method. Limb lengthening was done at the same treatment (monofocal treatment) or a separate osteotomy (bifocal treatment) was done after acute or gradual correction of the deformity using the Ilizarov hinge system. The external fixation time, amount of deformity correction, length gained, and incidence of complications were examined. Results were compared between monofocal versus bifocal treatment groups and between femoral versus tibial procedures. The average deformity corrected was 22.3 degrees, and the average lengthening was 44.4 mm. The external fixation index was 49.3 days/cm on average, ranging from 24.4 to 90 days/cm, and the mean duration of external fixation was 198 days, ranging from 77 to 352 days. Major complications requiring surgical treatment, such as premature consolidation and fracture, were seen in four patients. There were no statistically significant differences between the results for monofocal and bifocal treatment or treatment indices for femoral and tibial operations. The Ilizarov method was very effective for treatment of limb deformity combined with shortening. Monofocal treatment might be better if the total amounts of lengthening required are short to reduce surgical invasion. Longer treatment indices for tibial operations could not be verified from the current study.
    Clinical Orthopaedics and Related Research 10/2002; · 2.79 Impact Factor
  • M Abdel-Wanis, N Kawahara
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    ABSTRACT: Osteomalacia is rarely encountered in association with neurofibromatosis 1, characterized by phosphate loss in the urine and its pathogenesis is still unknown. Incidence of spinal deformities in cases of neurofibromatosis 1 associated with osteomalacia seems to be high. Spinal deformities are unlikely to be due to osteomalacia itself. Melatonin deficiency was proposed to be present in cases of neurofibromatosis 1 and to be an operating factor in progression of spinal deformities. We might hypothesize that putative melatonin deficiency in cases of neurofibromatosis 1 might play a role in the pathogenesis of hyperphosphaturea by decreasing sodium-phosphate cotransport, increasing the level of cAMP, the un-antagonized effect of dopamine on phosphate reabsorption and increasing glucocorticoid levels. Parathyroid overactivity that may occur secondary to osteomalacia might have synergistic effects with dopamine and further exaggerate phosphate loss in urine. On the other hand, excess corticosteroid secretion would decrease nocturnal melatonin level. Moreover, in the presence of hypophosphatemia, hypercortisolism might further inhibit melatonin secretion that might lead to progression of spinal deformities in these cases.
    Medical Hypotheses 09/2002; 59(2):183-5. · 1.18 Impact Factor
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    ABSTRACT: The prognostic value of the time of identification of lung metastasis was investigated in 280 patients with metastatic lung osteosarcoma as a multi-institutional study of the Japanese Musculoskeletal Oncology Group. The 280 patients with lung metastasis were divided into four groups: group 1, patients with lung metastasis identified at initial presentation; group 2, those with lung metastasis identified during preoperative chemotherapy; group 3, those with lung metastasis identified during postoperative chemotherapy, and group 4, those with lung metastasis identified after completion of treatment. Survivals of the four groups were compared. Additionally, the effects of number of metastatic nodules, metastasectomy, and the effect of chemotherapy on the primary tumor on survival of the four groups were analyzed. There were 46 patients in group 1, 30 in group 2, 94 in group 3, and 110 in group 4. The overall 2-year survival rates from the time of identification of lung metastasis were 33%, 31%, 24%, and 40% for groups 1, 2, 3, and 4, respectively, whereas the 5-year survival rates were 18%, 0%, 6%, and 31%, respectively. Patients in group 4 thus demonstrated significantly better prognosis than any of the other patients (P <.0001). Time of identification of lung metastasis is an important prognostic factor. In terms of clinical behavior, groups 2 and 3 are completely different than group 4. These data ensure the need to stratify stage III osteosarcomas into subgroups according to the time of diagnosis of lung metastases. To improve the survival of osteosarcoma patients, new treatment modalities should be introduced into the treatment armamentarium for lung metastasis from osteosarcoma, especially in groups 1, 2, and 3.
    Journal of Clinical Oncology 08/2002; 20(16):3470-7. · 18.04 Impact Factor
  • Spine 06/2002; 27(10):1124-6. · 2.16 Impact Factor
  • Mohamed E Abdel-Wanis, Norio Kawahara
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    ABSTRACT: We might hypothesize that the high rate of pseudarthrosis after spinal fusion for neurofibromatous scoliosis is related to two factors: the absence of neurofibromin and melatonin deficiency. Loss of the up-regulation of neurofibromin during the healing process might abolish the bone-forming effects mediated through platelet-derived growth factor (PDGF) and transforming growth factor (TGF) beta1. The absence of neurofibromin might cause an increase in the Ras activity that increases the mitogen-activated protein kinase (MAPK) with resultant disturbance of the regulatory mechanism of core binding transcription factor (Cbfa 1) and increase of osteocalcin. These effects might inhibit bone formation. Melatonin deficiency might cause defective bone formation and favour excess fibrous tissue formation.
    Medical Hypotheses 06/2002; 58(5):395-8. · 1.18 Impact Factor
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    ABSTRACT: We describe a consecutive series of 26 patients with simple bone cysts who were treated by curettage, multiple drilling and continuous decompression by the insertion of either a cannulated screw or a pin. In the first 15 patients we used titanium cannulated screws (group 1) and in the next 11 a cannulated hydroxyapatite pin (group 2). Satisfactory healing was achieved in 12 patients in group 1 (80%) and in all in group 2. This technique seems to be a promising option for the treatment of simple bone cysts. The cannulated hydroxyapatite pin is recommended because of its higher success rate and the fact that it does not need to be removed.
    Journal of Bone and Joint Surgery - British Volume 04/2002; 84(2):245-8. · 2.69 Impact Factor
  • M E Abdel-Wanis, H Tsuchiya
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    ABSTRACT: Three varieties of simple bone cysts have not attracted a lot of clinical attention: simple bone cysts in non-tubular bones, multiple cysts and epiphyseal cysts. Simple bone cysts occurring in non-tubular bones form about 4-10% of total cases, with a higher age incidence and better prognosis. Epiphyseal simple bone cysts have a higher age incidence, a lower male/female ratio, a very high humerus/femur ratio and higher incidence of tibial location than the classic metaphyseal cysts. Multiple cysts occur in the higher age group and show very high male predominance. In the review of the literature, 15 cysts (35.7%) were in non-tubular bones and six cysts (14.3%) were epiphyseal. They have a better prognosis than the classic metaphyseal ones. Four clinico-anatomic varieties of simple bone cysts could be recognized: classic metaphyseal, non-tubular, epiphyseal, and multiple. Venous obstruction might be the cause of all forms of the disease but the etiologies of venous obstruction causing the last three clinical forms might be different from that causing the classic metaphyseal ones.
    Medical Hypotheses 02/2002; 58(1):87-91. · 1.18 Impact Factor
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    ABSTRACT: This paper introduces an innovative technique of highly conservative limb-saving surgery for juxta-articular osteosarcoma. This technique consists of marginal tumour excision, joint preservation and reconstruction by distraction osteogenesis. Ten patients, with a mean age of 19.5 years and high-grade osteosarcoma, underwent this procedure. The distal femur and proximal tibia were affected in five patients each. After effective pre-operative chemotherapy, the tumour was excised with preservation of the epiphysis, the articular surface and the maximun amount of healthy soft tissue. This was followed by application of an external fixator. Bone transport was performed for seven patients and shortening-distraction for three. The limb function was rated excellent in seven patients, good in one and fair in two. At the final follow-up, three patients were dead after a mean of 25.3 months while seven patients remained free of disease with a mean follow-up of 55.4 months. Joint preservation and biological reconstruction through distraction osteogenesis can produce excellent and long-lasting functional results.
    Anticancer research 01/2002; 22(4):2373-6. · 1.71 Impact Factor
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    ABSTRACT: This study reviewed 14 patients with thyroid cancer spinal metastases treated between December 1984 and July 2000. In total the 14 patients had undergone 25 operations (average 1.8 operations/patient). The operations were at the thoracic (15), cervical (7) and lumbar (3) levels and operations included piecemeal excision (14), total en bloc spondylectomy (7), posterior decompression and stabilization (2), posterior decompression (laminectomy) (1) and posterior stabilization (1). Re-operations were due to local recurrence (8) or metastases to another level (2) or both (1). One patient died in the third postoperative day due to disseminated intravascular coagulopathy (DIC), 5 died due to the original illness after a mean of 67.8 months, while 8 patients are still living after a mean of 53.1 months. As long survival should be anticipated, in cases of thyroid cancer spinal metastases, a radical therapeutic attitude must be considered in decision-making. This should avoid the morbidity associated with local recurrence and revision surgery.
    Anticancer research 01/2002; 22(4):2509-16. · 1.71 Impact Factor
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    ABSTRACT: A 55-year-old Japanese woman presented with right knee pain of 1-month duration. Radiological studies revealed bilateral mild osteoarthritic changes in the medial knee joint compartment and symmetrical cysts in the upper tibial metaphyses, extending to the epiphyses. Intraosseous ganglion was considered the most probable diagnosis. However, intraoperatively, serous fluid-filled cavities were recognized; these were curetted and filled with hydroxyapatite granules. Histopathological examination of the cyst wall revealed thin fibrous tissue formed of collagen fibers without a lining cell layer, with scattered lymphocytes, histiocytes, irregular masses of fibrin-like material, and periosteal osteocartilagenous callus formation; a picture compatible with simple bone cysts. Bilateral symmetrical cysts of the upper tibial metaphyses extending to the epiphyses are extremely rare. A literature review revealed that the age incidence, and bony locations of multiple and epiphyseal simple bone cysts are atypical in relation to the classic metaphyseal simple bone cysts. Also, multiple and epiphyseal simple bone cysts have a better prognosis than the classic metaphyseal ones. Four clinicoanatomic varieties of simple bone cysts are recognized; classic metaphyseal, nontubular, epiphyseal, and multiple.
    Journal of Orthopaedic Science 10/2001; 6(6):595-600. · 0.96 Impact Factor

Publication Stats

485 Citations
56.71 Total Impact Points

Institutions

  • 2008
    • Sohag University
      Sawhāj, Sūhāj, Egypt
  • 2001–2007
    • Kanazawa University
      • • Department of Orthopaedic Surgery
      • • Department of Orthopedic Surgery
      Kanazawa-shi, Ishikawa-ken, Japan
    • Kanazawa Medical University
      • Department of Orthopaedic Surgery
      Kanazawa-shi, Ishikawa-ken, Japan