Traumatic atlantoaxial distractive instability: case report

We present an uncommon case of traumatic atlantoaxial distractive instability which manifested itself clinically in a respirator-dependent quadriplegic. The initial radiographic finding was anterior atlantoaxial dislocation. The patient was managed initially by halo traction and, 8 weeks later, demonstrated occipitocervical fusion with gratifying results.

Kinematics of the cervical spine canal: changes with sagittal plane loads

Spondylotic myelopathy is a result of decreased spinal canal space due to degeneration. The space also may change with physiological movements. The knowledge of the normal physiological changes is necessary for a better understanding of the clinical symptoms. Using a novel technique, we measured the changes in disk bulge, ligamentum flavum bulge, and anteroposterior canal diameter in response to tension-compression forces (up to 40 N each) and combined loading: 2 Nm of flexion or extension moment combined with 20 N compression force in five human cadaveric lower cervical spine specimens (C4-C7). From tension to compression, the average disk bulge changed 1.13 mm or 10.1% of the original canal diameter. The ligamentum flavum bulge changed 0.73 mm or 6.5% of the canal diameter. From flexion to extension the average disk bulb changed 1.16 mm or 10.8% of the canal diameter, whereas the ligamentum flavum bulge changed 2.68 mm or 24.3% of the canal diameter. Most of the changes in the bulges occurred with a small load application around the neutral position of the spine. The results of this study demonstrate that ligamentum flavum bulge can contribute significantly to canal encroachment in extension and that a flexed posture increases the sagittal diameter of the spinal canal.

Prognosticating factors in acetabular development following reduction of developmental dysplasia of the hip

A number of predictors that may influence acetabular development after reduction were studied in 75 hips with developmental dysplasia of the hip (DDH). Seventy-nine percent of the hips had satisfactory results of Severin group I or II, and 21% had unsatisfactory results. The best predictor of success in a unilateral case is the center-head distance discrepancy (CHDD) measurement at 1 year follow-up. Ninety-six percent of hips with a CHDD of < or = 6% had satisfactory results, whereas 78% with a CHDD > 6% had unsatisfactory results. This study also confirms that age at reduction and significant improvement in the acetabular index in the first year after reduction are important predictors.

Diverse applications of continuous lumbar drainage of cerebrospinal fluid in neurosurgical patients

From 1984 to 1991, continuous lumbar drainage (CLD) of cerebrospinal fluid (CSF) had been applied in 48 neurosurgical patients. Eleven of them had CSF accumulation and/or leakage at the operative sites and 37 of them suffered from CSF rhinorrhea. Successful treatment was achieved in 98% (47/48) of patients. There was neither death nor infection noted in this series. Complication was found in only one patient who developed acute subdural haematoma with pneumocephalus six days after CLD. After emergency craniotomy and evacuation of haematoma, the patient recovered without neurological deficit. The results suggest that CLD is a simple, safe and effective method in the treatment of CSF accumulation and/or leakage at the operative sites, as well as CSF rhinorrhea of various aetiologies.

Reappraisal of skeletal tuberculosis: role of radiological imaging

Skeletal tuberculosis (TB) can present with a broad spectrum of variable clinical manifestations which may cause diagnostic difficulties. To further elucidate these possible diagnostic pitfalls, 14 cases of bacteriologically or histologically proven skeletal TB, which were initially diagnosed otherwise, are reviewed. In five cases with lumbar or midthoracic spinal involvement, concomitant traumatic history and degenerative radiological changes were the main reasons for not suspecting the possibility of skeletal TB. A differential diagnosis between TB and metastatic lesions can be difficult in the very early stage when X-ray images usually have a low contrast and are not sharp. In nine cases with bone and joint involvement, a long-lasting discharging sinus led the clinician to an initial impression of septic arthritis; sometimes concomitant gouty arthritis can mask the clinical manifestations of skeletal TB. In five cases, minor erosive lesions over the peripheral margin of the involved bone were the earliest findings on the plain X-ray films and were overlooked. To facilitate the early diagnosis of skeletal TB and to avoid the possibility of complications in the management of patients, medical practitioners should be familiar with the usual forms of the condition and the wide variety of clinical manifestations.

An infrequent point mutation of the p53 gene in human nasopharyngeal carcinoma

Point mutations in the p53 gene have been detected in a variety of human cancers; the mutations are clustered in four "hot-spots" located in the coding region of exons 5, 7, and 8, which coincide with the four most highly conserved regions of the gene. We report the finding of a heterozygous G----C mutation at codon 280 (exon 8), position 2, of the p53 gene in a nasopharyngeal carcinoma (NPC) cell line, originating from Guangdong, a province in the People's Republic of China that leads the world in NPC incidence. A survey of nasopharyngeal tissues and NPC biopsies revealed that 1 out of 12 NPC samples from Hunan, another province in the People's Republic of China with high NPC incidence, had the same heterozygous mutation at codon 280 of p53, and none of 10 biopsies from Taiwan showed a mutation within exons 5-8 of the p53 gene. No other alteration of gene structure, including gross rearrangement or loss of heterozygosity or abnormality of gene expression was detected in NPC cell lines or NPC biopsies. We conclude from this study that mutational or other alterations of the p53 gene are not common in nasopharyngeal carcinogenesis and that a codon-280 mutation of p53 may be involved in less than 10% of NPC cases. This result contrasts with the relatively high frequency of p53 mutations associated with several other human carcinomas and suggests the importance of other genes in NPC genesis.

Microvascular decompression for hemifacial spasm: analyses of operative findings and results in 310 patients

The operative findings and results of microvascular decompression (MVD) on 310 Chinese patients with hemifacial spasm are analyzed in this report. The operations were performed at the Neurological Institute of the Veterans General Hospital-Taipei between January 1983 and June 1990. The length of follow-up ranged from 6 months to 8 years (mean, 4.3 years); 273 patients (88%) had complete relief of spasm within 3 days after one MVD, and the remaining 37 patients (12%) showed no immediate postoperative improvement. Sixteen (5.2%) of these 37 initially unresponsive patients subsequently experienced complete relief, which occurred from 4 days to 22 months (median, 21 days) after one MVD; 13 others (4.2%) had complete relief immediately after the second MVD; another 3 (1%) had delayed complete relief 6, 9, and 11 months after the second MVD, respectively; and the remaining 5 (1.6%) only had delayed partial relief, which occurred 2 to 9 weeks after one MVD. Late recurrence occurred in three patients (1%). These immediate and long-term results lend support to the conclusion that the timing of reoperation can be postponed for a period of 3 to 4 weeks in the event of an initial failure to get improvement, and that a second MVD may be of value.

[Effects of nasal continuous positive airway pressure on patients with obstructive sleep apnea syndrome]

To evaluate the efficacy of nasal continuous positive airway pressure (CPAP) on patients with obstructive sleep apnea syndrome, 20 patients with moderate to severe obstructive sleep apnea syndrome (respiratory disturbance index greater than or equal to 20) were studied. The patients were evaluated using the Grass polysomnograph model 78 during an overnight sleep one to two weeks apart with and without a nasal CPAP produced by 10 to 15 cm of water. The results showed that nasal CPAP significantly reduced the respiratory disturbance index (RDI) (p less than 0.001) and the desaturation index (p less than 0.001), and significantly raised the lowest oxygen saturation level. Nasal CPAP not only reduced RDI, but also improved the respiratory patterns during obstructive apnea events by shifting the obstructive apnea events to hypopnea events. Nasal CPAP also significantly decreased the relative time spent in stage 1 NREM sleep (p less than 0.001), and increased the relative time spent in stages 3+4 NREM and REM sleep (p less than 0.05). Most of the patients also felt better the morning after using nasal CPAP. Nasal CPAP significantly reduced the frequency and duration of apnea and the degree of nocturnal oxygen desaturation, and improved the respiratory patterns during obstructive apnea events, as well as the sleep architecture in obstructive sleep apnea patients. We conclude that nasal CPAP is effective in moderate to severe obstructive sleep apnea syndrome patients.

Plate fixation for anterior cervical interbody fusion

From April 1989 to April 1990, 13 patients with cervical spinal fracture/dislocation, spondylosis or metastasis were treated at the respective hospitals. There were 4 women and 9 men whose ages ranged from 25 to 70 years (mean 45 years). All of them were treated with neural decompression, bone grafting and anterior spinal interbody fusion. All iliac crest or fibular bone grafts were anchored to the vertebral bodies with plates and screws. The clinical outcomes were evaluated retrospectively. The results showed that all had improvement of neurological symptoms and signs. The radiographic evaluation revealed satisfactory alignment and sound union of the cervical spine in all 13 patients. No serious complications were found except screw loosening in two instances without impairment of clinical results. We concluded that anterior cervical plates provide effective stabilization which is essential for good results. Furthermore, from this study and a review of the literature, we advocated that it was not necessary for the tip of the screws to reach or even penetrate the posterior cortex of the vertebral body.