The inhalation effects of by-products from chlorination of heated indoor swimming pools on spinal development in pup mice

INTRODUCTION

It has been postulated that swimming in heated indoor swimming pools in the first year of life is associated with the development of spinal deformity in children. We explored in pup mice whether exposure to certain disinfection by-products resulting from chlorination of heated pools would affect the future development of the spinal column.

METHODS

Mice, from birth and for 28 consecutive days, were exposed to chemicals known to be created by disinfection by-products of indoor heated swimming pools. The study made use of a body fluid analogue and a chlorine source to recreate the conditions found in municipal pools. A cohort of 51 wild-type C57B6 mice, male and female, were divided into two groups: experimental (n = 29) and controls (n = 22). 24 mice were observed for 8 months (32 weeks), with 27 culled at 4 months (16 weeks). Serial CT scanning was used to assess the spines.

RESULTS

Exposure to disinfection by-products resulted in an increase in the normal thoracic kyphotic spinal angle of the mice when compared with their controls at 10 weeks; experimental mice kyphosis range 35-82° versus 29-38° in controls. At 14 weeks the kyphosis of the experimental mice had reduced in size but never to that of the control group.

CONCLUSION

We have demonstrated the ability to influence spinal development in pup mice through environmental factors and shown that the developmental deformity became evident only after a significant latent period.

Progressive Cervical Kyphosis Associated with Botulinum Toxin Injection

Weakness of the neck extensors can lead to "dropped head syndrome", a condition of progressive cervical kyphosis in which a patient is unable to hold their head up against the force of gravity. This condition can be associated with structural abnormalities of the spine as found in ankylosing spondylitis and vertebral fractures. Neuromuscular disorders, such as myasthenia gravis, muscular dystrophies, inflammatory myopathies, and motor neuron disorders such as amyotrophic lateral sclerosis (ALS) have also been reported as etiologies of dropped head syndrome. In this article, we describe an elderly woman with rapidly progressive cervical kyphosis following an injection of botulinum toxin A into her neck extensor musculature.

A surgical revisitation of Pott distemper of the spine

BACKGROUND CONTEXT

Pott disease and tuberculosis have been with humans for countless millennia. Before the mid-twentieth century, the treatment of tuberculous spondylitis was primarily supportive and typically resulted in dismal neurological, functional and cosmetic outcomes. The contemporary development of effective antituberculous medications, imaging modalities, anesthesia, operative techniques and spinal instrumentation resulted in quantum improvements in the diagnosis, management and outcome of spinal tuberculosis. With the successful treatment of tuberculosis worldwide, interest in Pott disease has faded from the surgical forefront over the last 20 years. With the recent unchecked global pandemic of human immunodeficiency virus, the number of tuberculosis and secondary spondylitis cases is again increasing at an alarming rate. A surgical revisitation of Pott disease is thus essential to prepare spinal surgeons for this impending resurgence of tuberculosis.

PURPOSE

To revisit the numerous treatment modalities for Pott disease and their outcomes. From this information, a critical reappraisal of surgical nuances with regard to decision making, timing, operative approach, graft types and the use of instrumentation were conducted.

STUDY DESIGN

A concise review of the diagnosis, management and surgical treatment of Pott disease.

METHODS

A broad review of the literature was conducted with a particular focus on the different surgical treatment modalities for Pott disease and their outcomes regarding neurological deficit, kyphosis and spinal stability.

RESULTS

Whereas a variety of management schemes have been used for the debridement and reconstruction of tuberculous spondylitis, there has also been a spectrum of outcomes regarding neurological function and deformity. Medical treatment alone remains the cornerstone of therapy for the majority of Pott disease cases. Surgical intervention should be limited primarily to cases of severe or progressive deformity and/or neurological deficit. Based on the available evidence, radical ventral debridement and grafting appears to provide reproducibly good long-term neurological outcomes. Furthermore, recurrence of infection is lowest with such techniques. Posterior operative techniques are most effective in the reduction and prevention of spinal deformity.

CONCLUSIONS

Unlike historical times, effective medical and surgical management of tuberculous spondyitis is now possible. Proper selection of drug therapy and operative modalities, however, is needed to optimize functional outcomes for each individual case of Pott disease.

A rare case of osteoporotic spine fracture associated with epidural lipomatosis causing paraplegia following long-term cortisone therapy

Cushing's syndrome is frequently associated with osteoporosis. Therefore, the incidence of osteoporotic spine fractures is significant. They are a rare cause of paraplegic syndromes. Additionally, epidural lipomatosis may occur in those patients. The combination of both fracture and lipomatosis may cause neurological deficit. A case of a young patient suffering from drug-induced Cushing's syndrome is reported. She developed progressive paraplegia. Radiographs demonstrated kyphosis of the thoracic spine from T7 to T9 and pathologic fractures. Urgent operation was planned to stabilize and decompress the spinal cord in the area of the kyphosis. Fortunately, magnetic resonance imaging (MRI) was conducted first. It confirmed pathologic fractures of T7-9 but also showed massive epidural fat extending from the level of T1 to T9. As suspected, laminectomy alone in the area of the fracture proved to be insufficient, as shown by myelography during operation. For treatment of paraplegia in this case of symptomatic epidural lipomatosis, an expanded laminectomy was necessary to remove all the epidural fat. Having undergone this procedure, the patient is now recovering from paraplegia. Our experience suggests that care should be taken before operative treatment of patients with pathological fractures in combination with Cushing's syndrome. In addition to vertebral fractures, epidural lipomatosis has to be taken into consideration. Those patients with neurological deficits have to be treated by an extensive laminectomy.

Gross vertebral collapse associated with long-term disodium etidronate treatment for pelvic Paget's disease

Inhibition of skeletal mineralisation is a well-recognized complication of disodium etidronate therapy that was identified in the earliest studies of its use in osteoporosis and Paget's disease. The effect is seen at lower doses in Paget's disease than in osteoporosis. Several cases of spontaneous fractures occurring in unaffected bones of Paget's patients have been reported. However, we believe the case described here is the most severe example of etidronate-induced osteomalacia published in the literature, featuring widespread vertebral collapse occurring as a consequence of nearly 10 years of uninterrupted etidronate treatment for isolated hemipelvic Paget's disease.

Adverse events during growth hormone therapy

The aim of this study was to ascertain the frequency of adverse events occuring during GH therapy in Australia and New Zealand since 1988. Data for children receiving GH has been collected prospectively on a national database, OZGROW, after informed consent has been given. Adverse events were coded by clinicians and have been analysed in relation to the nature of the event and the underlying diagnosis. There were 2922 subjects analysed, representing 9004 years of GH therapy. 151 subjects reported a total of 210 adverse events giving an overall frequency of 2.3% adverse events/patient treated year. Events that were probably related to GH therapy included peripheral oedema, injection site problems and increased frequency of kyphoscoliosis and slipped epiphysis in some groups. Adverse events were more frequent in growth hormone deficient children who had previously been treated for leukaemia, 8.1%, and in children previously treated for craniopharyngioma, 5.6%. A lower frequency was found for those with a diagnosis of idiopathic short stature, 1.6%, and familial short stature, 0.9%. Kyphoscoliosis was more frequently seen in Turner's syndrome, and slipped epiphyses in adolescent individuals with growth hormone deficiency, especially following treatment for leukaemia. There were no de novo tumours reported but the frequencies of recurrence/patient year for leukaemia, solid cranial tumours and craniopharyngioma were 1.1%, 2.2% and 3.8% respectively. A low frequency of adverse events has been reported on the OZGROW database but subsets of patients may be at increased risk of musculoskeletal abnormalities during GH therapy. The frequency of tumour recurrence during therapy is not different from known rates of recurrence in individuals not treated with GH.

The natural history and long-term follow-up of Scheuermann kyphosis

Sixty-seven patients who had a diagnosis of Scheuermann kyphosis and a mean angle of kyphosis of 71 degrees were evaluated after an average follow-up of thirty-two years (range, ten to forty-eight years) after the diagnosis. All sixty-seven patients completed a questionnaire; fifty-four had a physical examination and radiographs; fifty-two, pulmonary function testing; and forty-five, strength-testing of the trunk muscles. The results were compared with those in a control group of thirty-four subjects who were matched for age and sex. The patients who had Scheuermann kyphosis had more intense back pain, jobs that tended to have lower requirements for activity, less range of motion of extension of the trunk and less-strong extension of the trunk, and different localization of the pain. No significant differences between the patients and the control subjects were demonstrated for level of education, number of days absent from work because of low-back pain, extent that the pain interfered with activities of daily living, presence of numbness in the lower extremities, self-consciousness, self-esteem, social limitations, use of medication for back pain, or level of recreational activities. Also, the patients reported little preoccupation with their physical appearance. Normal or above-normal averages for pulmonary function were found in patients in whom the kyphosis was less than 100 degrees. Patients in whom the kyphosis was more than 100 degrees and the apex of the curve was in the first to eighth thoracic segments had restrictive lung disease. Five patients had an unexplained, mildly abnormal neurological examination. Mild scoliosis was common; spondylolisthesis was not observed.

Purkinje cell toxicity of beta-aminopropionitrile in the rat

Compounds causing neurolathyrism are putative aetiological agents in neurodegenerative disorders including amyotrophic lateral sclerosis. beta-Aminopropionitrile (BAPN) is one such compound. We have administered this lathyrogenic agent at a dose of 1 g/kg by the intraperitoneal route in experiments in adult Sprague-Dawley rats during a period of 10 weeks. The rats developed marked kyphoscoliosis, ataxia with paralysis and muscle wasting of the hind limbs. Vacuolation and loss of Purkinje cells developed, but no anterior horn cell degeneration was noted. Immunohistochemical studies of phosphorylated neurofilaments and the 72 kDa heat shock protein were normal and no intraneuronal ubiquitinated inclusions were seen. High-dose intraperitoneal BAPN in the rat causes Purkinje cell changes, but no other central nervous system abnormalities.