The Experts below are selected from a list of 273 Experts worldwide ranked by ideXlab platform
Kenji Nakanisi - One of the best experts on this subject based on the ideXlab platform.
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Effects of strain distribution in the intervertebral discs on the progression of ossification of the posterior longitudinal ligaments.
Spine, 1996Co-Authors: Shunji Matsunaga, Eiji Taketomi, Takashi Sakou, Kenji NakanisiAbstract:Study Design Strain distribution in the intervertebral discs was evaluated biomechanically using an engineering true strain calculation formula. Objectives This study was performed to clarify the involvement of dynamic factors in the progression of ossification of the posterior longitudinal ligament. Summary of Background Data In patients with ossification of the posterior longitudinal ligament of the cervical spine, ossification frequently progresses after laminectomy. This suggests the involvement of dynamic factors in the progression of ossification. However, these factors have not yet been clarified. Methods The analysis was performed on 101 patients with ossification of the posterior longitudinal ligament by employing dynamic lateral X-Ray Films of the cervical spine. The X-Ray Films were digitized and used as computer data for calculating the strain distribution. X-Ray Films were obtained again 5 years later, and the strain distribution and the presence or absence of progression of ossification were evaluated. Results The progression of ossification of the posterior longitudinal ligament was highly correlated with abnormal strain distribution in the intervertebral discs. Progression of ossification was frequently observed in areas having disc distortion in tension and eXtension on the posterior longitudinal ligament. Conclusions In this study, the area of progression of ossification corresponded to the area showing uneven strain distribution and resultant concentration of dynamic stress. These results suggest an important role for dynamic factors in the progression of ossification of the posterior longitudinal ligament.
Yoshiaki Toyama - One of the best experts on this subject based on the ideXlab platform.
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multicenter study investigating the postoperative progression of ossification of the posterior longitudinal ligament in the cervical spine a new computer assisted measurement
Journal of Neurosurgery, 2005Co-Authors: Kazuhiro Chiba, Itsuo Yamamoto, Hisashi Hirabayashi, Motoki Iwasaki, Hiroshi Goto, Kazuo Yonenobu, Yoshiaki ToyamaAbstract:Object. Ossification of the posterior longitudinal ligament (OPLL) often progresses after surgery, and this may cause late-onset neurological deterioration. There have been few studies, however, to clarify any correlation between progression and clinical outcome, partly because of the lack of studies involving reliable and reproducible methods by which detection of progression is made possible. The authors conducted a multicenter study to investigate the occurrence of postoperative progression and to elucidate the possible risk factors in a large-scale patient population, and a novel computer-assisted measurement method was used to provide the basis for future clinical studies. Methods. The authors analyzed lateral plain radiographs obtained immediately and at 1 and 2 years after surgery in 131 patients who underwent posterior decompression at 13 institutions. The X-Ray Films were transformed via scanner into digital images; the length and thickness of ossifications were measured using a new computer-assi...
Jeffrey L Lovallo - One of the best experts on this subject based on the ideXlab platform.
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scapholunate advanced collapse pattern of arthritis in calcium pyrophosphate deposition disease of the wrist
Journal of Hand Surgery (European Volume), 1993Co-Authors: William Doherty, Jeffrey L LovalloAbstract:Chondrocalcinosis is a well-described radiographic finding in patients with calcium pyrophosphate dihydrate deposition disease of the wrist and other joints. The medical records and X-Ray Films of 12 patients evaluated over an 18-month period for chondrocalcinosis of the wrist were eXamined for symptoms and physical and X-Ray film findings. Thirteen wrists were affected. All wrists were noted to have calcification of the triangular fibrocartilage compleX. Twelve of 13 wrists had the characteristic features of the scapholunate advanced collapse pattern of arthritis. In addition, there was a correlation in our series between chondrocalcinosis and carpal tunnel syndrome. Destruction of the interosseous soft tissues caused by crystalline deposition could alter the biomechanics of the wrist in a similar fashion to that of the post-traumatic scapholunate advanced collapse wrist leading to arthritic symptoms.
Peter S Barre - One of the best experts on this subject based on the ideXlab platform.
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dynamic digital traction for unstable comminuted intra articular fracture dislocations of the proXimal interphalangeal joint
Journal of Hand Surgery (European Volume), 1995Co-Authors: John P Morgan, Douglas A Gordon, Mark S Klug, Paul E Perry, Peter S BarreAbstract:Unstable intra-articular fracture-dislocations about the proXimal interphalangeal joint present a formidable management dilemma. Fourteen patients with comminuted injuries of the proXimal interphalangeal joint were treated with dynamic digital traction and followed for an average of 24 months. Dorsal fracture-dislocation and pilon-type injuries made up the majority of cases. Average proXimal interphalangeal joint articular surface involvement was 80%. Immediate motion was instituted after traction application. The device was applied in the office with readily available materials. At final follow-up eXamination, active arc of motion averaged 89° at the proXimal interphalangeal joint and 95° for patients sustaining isolated injuries. X-Ray Films revealed fracture union, joint remodeling, and preservation of joint space. Patient satisfaction was high, with return to previous levels of activity and eXcellent functional joint restoration. Dynamic digital traction is recommended for unstable proXimal interphalangeal joint fractures with comminution, including those associated with subluXation or dislocation.
Shunji Matsunaga - One of the best experts on this subject based on the ideXlab platform.
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Effects of strain distribution in the intervertebral discs on the progression of ossification of the posterior longitudinal ligaments.
Spine, 1996Co-Authors: Shunji Matsunaga, Eiji Taketomi, Takashi Sakou, Kenji NakanisiAbstract:Study Design Strain distribution in the intervertebral discs was evaluated biomechanically using an engineering true strain calculation formula. Objectives This study was performed to clarify the involvement of dynamic factors in the progression of ossification of the posterior longitudinal ligament. Summary of Background Data In patients with ossification of the posterior longitudinal ligament of the cervical spine, ossification frequently progresses after laminectomy. This suggests the involvement of dynamic factors in the progression of ossification. However, these factors have not yet been clarified. Methods The analysis was performed on 101 patients with ossification of the posterior longitudinal ligament by employing dynamic lateral X-Ray Films of the cervical spine. The X-Ray Films were digitized and used as computer data for calculating the strain distribution. X-Ray Films were obtained again 5 years later, and the strain distribution and the presence or absence of progression of ossification were evaluated. Results The progression of ossification of the posterior longitudinal ligament was highly correlated with abnormal strain distribution in the intervertebral discs. Progression of ossification was frequently observed in areas having disc distortion in tension and eXtension on the posterior longitudinal ligament. Conclusions In this study, the area of progression of ossification corresponded to the area showing uneven strain distribution and resultant concentration of dynamic stress. These results suggest an important role for dynamic factors in the progression of ossification of the posterior longitudinal ligament.