Spinal Column Deformity Research Articles

En bloc laminoplasty performed with threadwire saw.

To introduce a method for a simple, nonexpansive laminoplasty that can be performed with a threadwire saw (T-saw) after en bloc laminotomy has been performed. The method can be applied along the entire spinal region, including the thoracic and lumbar spine. An en bloc laminotomy of trapezoid shape at the cross section is performed bilaterally at the junctional area of the lamina and facet joint with a thin, flexible T-saw, while preserving the supraspinous, interspinous, and interlaminar ligaments. After the intradural procedure has been performed, the laminar flap is replaced in its original site and fixed with 1-0 nylon sutures, resulting in the complete reconstruction of the posterior supporting elements of the spinal column. En bloc laminoplasty was performed on 16 patients via a T-saw; most of the patients had intradural spinal tumors. The patients did not need their spinal canals to be enlarged after the intradural procedure had been performed. The follow-up period ranged from 2 to 40 months (mean +/- standard error, 22.6 +/- 3.4 mo). The laminoplasty was performed from the upper cervical to the sacral regions, although the most frequently operated level was the lower thoracic level. Two-level laminoplasty was performed in 12 patients, and three-level laminoplasty was performed in four. The laminoplasty was done safely and without any complications, except in one patient, who experienced thoracic root injury from a T-saw that was accidentally inserted anterior to the roots. No spinal column deformity or sinking of the replaced laminar flap was noted during the follow-up period; patients were assessed at follow-up via radiographs or computed tomographic scans. Computed tomographic scans obtained later indicated that bony fusion occurred at the cutting edges 1.0 to 4.0 months after surgery (mean, 1.90 +/- 0.34 mo). Simple en bloc laminoplasty performed with a T-saw is a useful, safe procedure that can be used to reconstruct the posterior spinal elements throughout the whole spinal region after the intradural procedure has been performed.

Association of a lordosis-scoliosis-kyphosis deformity in gilthead seabream (Sparus aurata) with family structure

Skeletal deformities constitute a major problem for aquaculture industry by decreasing the final value of the fish. An analysis of skeletal malformations in 11,640 fish was performed considering families and triplicates per family. Thirtynine different skeletal abnormalities were detected, such as lordosis, vertebral fusion, absence of one or both operculum, bent-jaw, etc. Moreover, a new unusual complex spinal column deformity consisting of a consecutive repetition of lordosis, scoliosis and kyphosis (LSK) from the head to the caudal fin was described. This syndrome was statistically associated with the family structure (Z2H−family,LSK=3.49; p<0.05). The incidence of this deformity was 0.2% in the whole population, and 6.5% within the affected family (2H). The environmental and genetic causes are discussed.

Treatment of spinal cord tumors in children.

A retrospective review was carried out of nine children under 17 years of age with a diagnosis of intramedullary tumor seen during the period 1989-1995. Six had astrocytomas; one each had an ependymoma, a PNET, and a choroid plexus papilloma. Five patients had back pain, 3 others had mild pareses and the ninth had incapacitating defects. Seven of the 9 were treated by subtotal extirpation of the lesion, and biopsy alone was performed in the other two. All tumors were low grade (grade I or II) and therefore radiation therapy (RT) was performed as the only postoperative treatment in 8 of the 9 children. In February 1996, seven (77.8%) children were alive and two (22.2%) died of recurrent tumor (7 months and 5 years after diagnosis, respectively). Median follow-up was 3 years 4 months (range: 1 year 6 months to 7 years 3 months). Surgical removal of intraspinal tumors provides the best hope of control, but spinal column deformity after laminectomy and irradiation is a serious long-term problem in children. Orthopedic supervision for the prevention of these deformities; e.g., by external immobilization, is mandatory.

Spinal column deformity and instability after lumbar or thoracolumbar laminectomy for intraspinal tumors in children and young adults.

A retrospective study about the occurrence of spinal column deformity or instability after multilevel lumbar or thoracolumbar total laminectomy for removal of benign intraspinal tumors in children and young adults. To analyze the long-term clinical and radiographic outcome of these patients, and to specify factors that affect the occurrence of postlaminectomy spinal column deformity and instability. Spinal column deformity is not uncommon after multilevel cervical or thoracic laminectomies for removal of intraspinal tumors in children. Its incidence in the lumbar and thoracolumbar spine reportedly is low. Thirty-six consecutive patients (23 male, 13 female) underwent multilevel lumbar or thoracolumbar total laminectomy for removal of benign intraspinal tumors from 1966 to 1989. Twelve patients were aged 17 years or younger ("children and adolescents"; mean age, 11 years), and 24 were aged 18-30 years ("young adults"; mean age, 24 years). All patients had preoperative, immediate postoperative, and follow-up clinical and radiographic examinations. At a mean follow-up period of 14 years (range, 4-28 years), six patients (16.6%) had spinal deformity (lordosis or thoracolumbar kyphosis associated with scoliosis), and four (11%) had spondylolisthesis. Spinal column deformity occurred in 33% of children and adolescents and in 8% of young adults. Spondylolisthesis occurred in 16.6% of children and adolescents and in 8% of young adults. Three patients had fusion for spinal column deformity. Pain was present in eight patients, and other neurologic signs and symptoms were found in 18. There was an increased incidence of postoperative spinal deformity in patients who had more than two laminae removed (P < 0.01) or a facetectomy performed at the time of the initial operation (P < 0.05). There was no association between the occurrence of the deformity and sex, neurologic condition after laminectomy, or length of follow-up period. Spinal deformity or instability after multilevel lumbar or thoracolumbar total laminectomy is not uncommon in children and adolescents. Limiting laminae removal and facet destruction may decrease this incidence. Fusion may be required to correct post-laminectomy deformity and to stabilize the spine.

Management of intramedullary tumours in children.

Clinical presentation, diagnosis, surgical technique and results of 25 cases of intramedullary tumours in patients under 16 years of age are analyzed. Pre-operative spinal deformity was present in 9 patients. Surgery was performed in all. After multilaminectomy with preservation of the intervertebral joints, total removal of the lesion was achieved in 11 patients and subtotal removal in 14 others. After surgery, external immobilization lasting an average period of 5 years was instituted in all patients. Postoperative radiation therapy was performed in 11 cases (5 "high grade" astrocytomas, 5 ependymomas, 1 glioblastoma). There were 11 recurrences: 4 of which (2 ependymomas and 2 "low grade" astrocytomas) were treated surgically, 7 (5 "high grade" astrocytomas, 1 glioblastoma, 1 oligodendroglioma) with palliative radiation treatment. Six patients eventually developed postlaminectomy spinal deformities as diagnosed roentgenographically 6 to 50 months postoperatively. Of the 16 patients still alive, 7 did not present relevant neurological deficit, 1 presented a monoparesis, while the other 8 presented invalidating deficits. Surgical treatment did not differ from that employed in the intramedullary tumours in the adult: radical resection is indeed the optimal therapeutic origin. The risk of radiation therapy are greater in children: it is crucial to limit radiation therapy to only some histotypes. The incidence of spinal column deformity after multilevel laminectomy is greater in young patients. It is advisable to implement prevention of spinal deformities by postoperative external immobilization and constant follow-up so as to detect early changes of spinal stability.

Osteological abnormalities in laboratory reared sea-bass ( Dicentrarchus labrax) fingerlings

Two groups of juvenile sea-bass, a random group and a group selected on the criteria of the appearance of macroscopically visible body deformations or anomalies in behaviour, were collected from the rearing tanks, treated for cartilage-bone staining with alizarin and alcian-blue, and examined for osteological abnormalities. The meristic characters of the stained specimens were also examined. The percentage occurrence and the interrelationship of the various abnormality types are described. The most frequently encountered abnormalities were those involving spinal column and vertebral deformities and these were often associated with swimbladder deficiencies.

Analysis and Prevention of Spinal Column Deformity Following Cervical Laminectomy I

Postlaminectomy deformities were simulated in the cervical or cervicothoracic spine by the use of a displacement incremental method based on finite-element analysis combined with composite material and spanning element theory. The simulation analyses revealed that the primary cause of postlaminectomy deformity was the resection of one or more spinous processes and/or posterior ligaments (ie, ligamenta flava, supraspinous, and interspinous ligaments). After their removal, the tensile stresses that were preoperatively distributed through the posterior ligaments were transferred to the facets. This led to an imbalance of the stresses on the spinal bodies, causing deformity. The gravitational center of the head determined whether the deformity would develop as a kyphosis or increasing lordosis. As the elastic modulus of the soft tissue composites (eg, end plates, ligaments, and facets) increased, a kyphotic deformity changed gradually from swan-neck deformity, to extreme kyphotic deformity with a large curvature, and finally to a straightening deformity. Progressive kyphotic deformity is found only in children.

Ovine Arthrogryposis and Central Nervous System Malformations Associated with in utero Cache Valley Virus Infection: Spontaneous Disease

Gross appearance and histologic lesions seen in 15 newborn lambs in an outbreak of congenital arthrogryposis with hydrocephalus or hydranencephaly (CAH) in Texas are described. Severe arthrogryposis with skeletal muscle hypoplasia was seen in limbs of affected lambs. Spinal column deformities were also present. Multiple central nervous system (CNS) malformations were present in CAH lambs including micrencephaly, cerebellar hypoplasia, micromelia, hydrocephalus, hydranencephaly, and porencephaly. Histologic lesions consisted primarily of areas of necrosis and loss of the paraventricular neuropil and motor neurons in the CNS and a resolving myositis with poorly developed myotubular myocytes in skeletal muscle. Seroepidemiologic studies on the flock and serologic data from heart blood taken from the stillborn affected lambs indicated that the outbreak was due to in utero infection with Cache Valley Virus.

The neurological and skeletal outcome in patients with closed cervical spinal cord injury.

Sixty-one patients with closed cervical spinal cord injury were cared for within a defined protocol and followed for at least 1 year. Neurological recovery and healing of spinal structures were evaluated at intervals. Forty-three patients were managed without surgical intervention at the site of spine trauma, and the incidence of spontaneous fusion ("autofusion") was noted. Surgical fusion was performed on 17 patients, mainly to restore spinal stability and alignment. One patient underwent laminectomy without fusion. In both the surgical fusion and the autofusion groups, there were significant numbers of patients who improved neurologically, including some designated as having a complete spinal cord lesion at the initial neurological examination. As expected, better spinal alignment was achieved in the surgical group, although alignment in the nonsurgically treated group was generally acceptable. The majority of patients developed radiographically apparent callus formation anterior to the injured vertebral bodies, regardless of the mechanism of injury or the method of treatment. After 3 months all patients who underwent surgical fusion achieved spinal stability, as did the majority of patients in the autofusion group. Only individuals with flexion-distraction injuries who did not undergo surgical fusion appeared to be at risk for progressive spinal column deformity. Neither retropulsion of bone fragments nor angulation at the fracture site appeared to correlate with a poor neurological outcome, since improvement in neurological function occurred similarly in patients with and without these deformities.

Incidence of spinal column deformity after multilevel laminectomy in children and adults.

Fifty-eight patients, all less than 25 years of age, underwent multilevel laminectomy for conditions that in themselves do not usually cause spinal deformity. Spinal deformity developed in 46% (12 of 26) of the patients who were less than 15 years of age, but in only 6% (two of 32) of the patients aged 15 to 24 years. Spinal deformity developed in all (100%) patients who had cervical laminectomy, in 36% of those who had thoracic laminectomy, and in none (0%) of those who had lumbar laminectomy. There was no correlation between the occurrence of deformity and sex, number of laminae removed, neurological conditions after laminectomy, or length of time after surgery.

Intramedullar epidermoid successfully operated upon.

Authors report on an intramedullar epidermoid successfully operated upon. It was accompanied with malformation of vertebrae and deformity of spinal column. They think the good result is due to the early operation.