Kinetic change of spinal cord compression on flexion-extension magnetic resonance imaging in cervical spine.

OBJECTIVE: We aimed to determine the changes in cervical canal diameters and spinal cord compression at each level from C2-3 to C7-T1 in flexion and extension positions and to study the use of flexion-extension magnetic resonance imaging (MRI). We also aimed to assess the changes in the length of the spinal cord in flexion and extension positions of the cervical spine. PATIENTS AND METHODS: Flexion-extension MRI scans were performed consecutively on sixty-six patients with neck pain with/without neurogenic symptoms of the cervical spine. All patients were treated conservatively. We investigated the length of the cervical spinal cord (LSC), length of the cervical spinal anterior column (LAC), length of the cervical spinal posterior column (LPC), spinal canal diameter, and severity of cord compression in flexion, neutral, and extension positions. RESULTS: At each intervertebral level (from C2-3 to C7-T1), the average spinal canal diameter showed significant decrease from flexion to extension positions (P < 0.05). The average LSC, LAC, and LPC were decreased on extension of the neck compared with flexion (P < 0.05). Higher stages were found in extension position than in flexion position with statistically significant differences (P < 0.05). CONCLUSION: The use of flexion-extension MRI may demonstrate true pathology that contributes in the pathogenesis of cervical degenerative disease (CDD). Higher stages in spinal cord compression were found in extension position than in flexion position. However, higher stages in spinal cord compression in extension position did not necessarily cause severe myelopathy. This finding is an important evidence for conservative therapy on patient neck position education.

High intensity zone in lumbar spine and its correlation with disc degeneration.

Purpose; To investigate the prevalence, clinical significance of high intensity zone (HIZ), and associated disc degeneration. Materials and methods; We undertook retrospective analysis of 228 patients, aged from 15 to 55 years, who had undergone magnetic resonance (MR) imaging of lumbar spine in outpatient clinic from 2013 to 2014. HIZ was defined as a presence of high intensity signal in the annulus on T2-weighted images. All HIZ positive discs were classified according to Pfirrmann grading system for presence of disc degeneration. Results; Forty-three patients (18.8%) with 53 intervertebral discs demonstrated HIZ. There was no significant predominance about age and gender for the presence of HIZ. HIZ occurred mainly at L4-5 (43.3%) and L5-S1 (30.2%) levels, infrequently at L3-4 (17%) and rarely at upper levels. The prevalence of disc degenerations with Pfirrmann grade 3, 4, and 5 were significantly higher in HIZ positive patients than in randomly selected 35 HIZ negative patients (64% vs. 46%, respectively). Conclusion; In this study we identified that the presence of HIZ was directly proportional to increased incidence of disc degeneration in remaining lumbar discs. The prevalence of significant degeneration was significantly higher in HIZ positive patient at lower three lumbar levels. J. Med. Invest. 64: 39-42, February, 2017.

Radiographic changes of cervical destructive spondyloarthropathy in long-term hemodialysis patients: A 9-year longitudinal observational study.

Analyses of radiographic changes and clinical symptom of destructive spondyloarthropathy (DSA) on consecutive 42 patients managed with long-term hemodialysis were performed to elucidate radiographic changes of DSA and the factors that influence to the destructive changes. Patients underwent plain radiographs of the cervical spine with 9 years interval. Grading of radiological feature from lateral view was classified into grade 0 to grade 3. Clinical symptom was evaluated using modified Japanese Orthopaedic Association scoring system for cervical myelopathy (mJOA score). Destructive changes were observed in 3 patients at the first examination, and those were observed in 15 patients 9 years after the first examination. There is no statistically significant difference between the duration of hemodialysis and the grade. The mean age at the onset of hemodialysis, however, was significantly higher in patients of grade 2 and 3 than those of grade 1. Older patients with long-term hemodialysis had destructive changes. Destructive changes commonly observed in lower cervical spine. The average numbers of the involved disc level were 1.6 in grade 2 and 1.0 in grade 3. Clinical symptoms were varied in each grade and there was no statistically significant difference in total mJOA score among these grades. J. Med. Invest. 64: 68-73, February, 2017.

Clinical Significance of High-intensity Zone for Discogenic Low Back Pain: A Review.

High-intensity zone (HIZ) was originally described as a high-intensity signal on T2-weighted magnetic resonance (MR) images, located in the posterior annulus fibrosus, clearly separated from the nucleus pulposus. Among symptomatic patients with low back pain, HIZ is present in 28-59% of cases. In morphologically abnormal discs, high sensitivity and specificity of 81% and 79%, respectively, were reported for HIZs and concordant pain during discography. In contrast, another report indicated low rates. Although most papers reported high sensitivity and specificity for this relationship, it remains controversial. Regarding the pathology of HIZs, inflammatory granulation tissues are found at sites showing HIZs. Such inflammatory tissues produce pro-inflammatory cytokines and mediators, which sensitize the nociceptors within the disc and cause pain. An effective treatment for this condition is yet to be established. Recently, minimally invasive surgery using percutaneous endoscopic discectomy (PED) under local anesthesia was introduced. After removal of the degenerated disc material, the HIZ is identified with the endoscope and then coagulated and modulated with a bipolar radio pulse. This technique is called thermal annuloplasty. In conclusion, HIZs is an important sign of painful intervertebral disc disruption, if identified precisely based on factors such as location and intensity.

Optimizing baseplate position in reverse total shoulder arthroplasty in small-sized Japanese females: technical notes and literature review.

The management of cuff tear arthropathy (CTA) has always been a challenge for shoulder surgeons. Introduction of reverse total shoulder arthroplasty (RTSA) helped in providing pain relief and improved shoulder function in patients with CTA. In this study, we aimed to evaluate the short-term clinical results and some clinical details regarding the types of available prosthesis, positioning, and size of the components for RTSA in a population of short-stature female Japanese. In our seven cases, the average glenoid size was 23.9 mm in width and 34.2 mm in height. The average width was smaller than the size of all available baseplates. We implanted reverse shoulder prostheses with baseplate that measured 28 mm in diameter and two locking screws. The center of the baseplate was shifted to allow slight anterior overhang relative to the anatomical center to avoid breakage of the posterior cortex and to achieve firm fixation. One case of humeral shaft fracture occurred while inserting the humeral stem and required encircling wiring. In our experience, the short term clinical results of RTSA were excellent, but a new prosthesis that is designed to fit the short stature of Asians with smaller glenoid and humerus should be considered.

Stress fracture of the thoracic spine in an elite rhythmic gymnast: A case report.

Spondylolysis, a defect or stress fracture of the vertebral pars interarticularis, occurs most frequently in the lower lumbar spine and occasionally in the cervical spine, but is extremely rare in the thoracic spine. We report the case of a 17 year-old girl, an elite rhythmic gymnast, who reported with early-stage thoracic spondylolysis at T10 and T11 levels. Physicians should be aware that performance of unusual athletic movements, such as those by gymnasts, may lead to spondylolysis in rare locations.

Postoperative discal cyst: An unusual complication after microendoscopic discectomy in teenagers.

Various complications after microendoscopic discectomy (MED) are well known, but postoperative discal cyst is a unique and relatively unknown complication. Here, we report on two teenage patients who presented with postoperative discal cyst after MED for herniated nucleus pulposus (HNP), which resolved after conservative treatment. The patients were diagnosed with HNP at L4-5 and L5-S1 based on MRI and then treated by MED. Postoperative discal cyst was diagnosed on MRI after recurrence of symptoms. Both patients were managed conservatively. T2-weighted MRI demonstrated hyperintense collections adjacent to the operated intervertebral disc level, which were communicating with the corresponding disc annulus. Because the clinical symptoms were relatively mild, the patients were managed conservatively; both made a complete clinical recovery with radiological evidence of improvement. Postoperative discal cyst is a relatively unknown complication after MED for HNP. Surgeons should be aware of this postoperative complication when operating on young individuals with HNP.

Hysterical conversion paralysis in an adolescent boy with lumbar spondylolysis.

We describe a case of recurrent hysterical paralysis triggered by low back pain because of lumbar spondylolysis. A 16-year-old male soccer player was referred to our institution with five previous episodes of acute paralysis triggered by severe low back pain. We performed direct surgical repair of the terminal-stage bilateral spondylolysis at L4 using a hook-rod system. His chronic low back pain was completely resolved, and no further episodes of hysterical paralysis have occurred after surgery. Spine surgeons should be aware of possible hysterical conversion paralysis when there is discrepancy between radiological and neurological findings.

Percutaneous Endoscopic Discectomy via Transforaminal Route for Discal Cyst.

Background. Discal cyst has been identified as a rare cause of low back pain and radiating leg pain. The pathogenesis and management of this condition are still debated. The largest number of reported cases had undergone microsurgery while very few cases have been treated with percutaneous endoscopic discectomy (PED). Methods. An 18-year-old boy complained of low back pain radiating to right leg after a minor road traffic accident. Diagnosis of a discal cyst at L4-L5 level was made based on magnetic resonance imaging (MRI). Despite conservative management for 6 months, the low back pain and radiating leg pain persisted so surgical treatment by PED was performed under local anesthesia. As the patient was a very active baseball player, his physician recommended a minimally invasive procedure to avoid damage to the back muscles. Results. The patient's low back pain and leg pain disappeared immediately after surgery and he made a rapid recovery. He resumed mild exercise and sports practice 4 weeks after surgery. Complete regression of the cystic lesion was demonstrated on the 2-month postoperative MRI. Conclusion. A minimal invasive procedure like PED can be an effective surgical treatment for discal cyst, especially in active individuals who play sports.

A review of the pathomechanism of forward slippage in pediatric spondylolysis: the Tokushima theory of growth plate slippage.

Spondylolysis is a stress fracture of the pars interarticularis, which in some cases progresses to spondylolisthesis (forward slippage of the vertebral body). This slip progression is prevalent in children and occurs very rarely after spinal maturation. The pathomechanism and predilection for children remains controversial despite considerable clinical and basic research into the disorder over the last three decades. Here we review the pathomechanism of spondylolytic spondylolisthesis in children and adolescents, and specifically the Tokushima theory of growth plate slippage developed from our extensive research findings. Clinically, we have observed the slippage site near the growth plate on MRI; then, using fresh cadaveric spines, we found the weakest link against forward shear loading was the growth plate. We subsequently developed an immature rat model showing forward slippage after growth plate injury. Moreover, finite element analysis of the pediatric spine clearly showed increased mechanical stress at the growth plate in the spondylolytic pediatric spine model compared with the intact pediatric spine. Thus, spondylolysis progresses to spondylolisthesis (forward slippage) in children and adolescents with the growth plate as the site of the slippage. Repetitive mechanical loading on to the growth plate may serve to separate the growth plate and subsequently progress to spondylolisthesis.

Percutaneous endoscopic lumbar discectomy for a huge herniated disc causing acute cauda equina syndrome: a case report.

Microsurgery for lumbar disc herniation that requires surgical intervention has been well described. The methods vary from traditional open discectomy to minimally invasive techniques. All need adequate preanesthetic preparation of patients as general anesthesia is required for the procedure, and nerve monitoring is necessary to prevent iatrogenic nerve injury. Conventional surgical techniques sometimes require the removal of the corresponding lamina to assess the nerve root and herniated disc, and this may increase the risk for posterior instability of the vertebral body. Should this occur, fusion surgery may be needed, further increasing morbidity and cost. We present here a case of lumbar herniated disc fragments causing acute cauda equina syndrome that were endoscopically resected through a transforaminal approach in an awake patient under local anesthesia. Percutaneous endoscopic discectomy under local anesthesia proved to be a better alternative to open back surgery as it made immediate intervention possible, was associated with fewer perioperative complications and morbidity, minimized soft tissue damage, and allowed early rehabilitation with a better outcome and greater patient satisfaction. In addition to these advantages, percutaneous endoscopic discectomy protects other approaches that may be needed in subsequent surgeries, whether open or minimally invasive.