Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “KYPHOSIS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5Linked to original sources
PubMed1978

Kyphosis in childhood and adolescence.

Kyphosis has become an increasingly important problem to the surgeon interested in the management of significant spinal deformity. As scoliosis has become better understood, the more difficult problems have become apparent and one of the most difficult of these is kyphosis. Kyphosis is the deformity which can produce paraplegia if it progresses to a significant degree and remains untreated. Contrary to scoliosis, in which bracing and posterior fusion alone are usually quite sufficient, kyphosis sometimes responds to bracing and other times it does not. If surgical treatment is necessary it quite often requires an anterior fusion. The purpose of this presentation is to give an overall review of the various etiologies of kyphosis and the current status of management of these various problems.

Adolescent↗
PubMed2000

The effect of kyphosis on the mechanical strength of a long-segment posterior construct using a synthetic model.

STUDY DESIGN: This experimental study used synthetic spine models to compare the effect of the angle of kyphosis, rod diameter, and hook number on the biomechanical stiffness of a long-segment posterior spinal construct. OBJECTIVE: To examine the biomechanical effects of incremental kyphosis on variously instrumented long-segment posterior spinal constructs. SUMMARY OF BACKGROUND DATA: Euler's formula for loading of curved long columns would suggest that kyphosis has a profound impact on the biomechanical behavior of long-segment posterior spinal constructs. The effects of sagittal contour on the mechanical properties of long-segment posterior spinal constructs have not been well documented. METHODS: Kyphotic and straight synthetic spine models were used to test long-segment posterior instrumentation constructs biomechanically while varying rod diameter and the number of hook sites. The synthetic spines, composed of polypropylene vertebral blocks and isoprene elastomer intervertebral spacers, were fabricated with either 0 degrees, 27 degrees, or 53 degrees of sagittal contour. The models were instrumented with 5.5- or 6.35-mm titanium rods, and with either 8 or 12 hooks. The models were loaded from 0 to 300 N in a cyclical ramp fashion using an MTS 858 Bionix testing device testing device. Construct stiffness (force and displacement) during axial compression was determined. RESULTS: Straight model: Changing the hook number from 8 to 12 caused a 32% increase in construct stiffness with the 5.5-mm rod. Changing the rod diameter from 5.5 to 6.35 mm caused a 36% increase in construct stiffness with the 8-hook pattern. Changing both the rods and hooks caused the stiffness to increase 44%. 27 degrees MODEL: Changing the hook number from 8 to 12 caused a 20% increase in construct stiffness with the 6.5-mm rod. Changing the rod diameter from 5.5 to 6.35 mm caused a 29% increase in construct stiffness with the 12-hook pattern. Changing both the rods and hooks caused the construct stiffness to increase 26%. 53 degrees MODEL: Changing the hook number from 8 to 12 caused a 14% increase in construct stiffness with the 6.35-mm rod. Changing the rod diameter from 5.5 to 6.35 mm caused a 17% (P<0.0005) increase in construct stiffness with the 12-hookpattern. Changing both rods and hooks caused the stiffness to increase 21%. Summary data on angular kyphosis: Using the same rod diameter and the same number of hooks, and progressing from a straight alignment to 27 degrees of sagittal contour decreased construct stiffness 32%. Going from straight alignment to 53 degrees decreased the stiffness 59.6%. All reported values were statistically significant (P < 0.0005). CONCLUSIONS: The biomechanical stiffness of the straight spine was sensitive to both an increase in hook fixation sites and an increase in rod diameter. The kyphotic spines, however, were more sensitive to variations in rod diameter. Although with increasing kyphosis, the optimum instrumentation strategy will maximize both rod diameter and the number of hook sites, instrumented kyphotic spines remain biomechanically "disadvantaged" as compared with nonkyphotic instrumented spines.

Bone Nails↗
PubMed2002

Exertional myelopathy in type 2 congenital kyphosis.

STUDY DESIGN: A case of lower-extremity myelopathy induced by physical exertion in a patient with Type 2 (failure of segmentation) congenital kyphosis is reported. OBJECTIVE: To describe the uncommon presentation of neurologic sequelae in a patient with Type 2 congenital kyphosis. SUMMARY OF BACKGROUND DATA: Various reports have described neurologic sequelae in patients with Type 1 (failure of formation) congenital kyphosis. To the authors' knowledge, no case of Type 2 congenital kyphosis leading to neurologic symptoms has been reported. METHODS: A 17-year-old boy presented with a 3-year history of progressively worsening midthoracic back pain. During exertion, numbness developed along the posterior aspects of his legs, and he experienced a wobbly sensation in his lower extremities that prevented his participation in athletic activities. His static and dynamic neurologic examination was unremarkable. However, he developed a wide-based clumsy myelopathic gait when he was asked to run in the halls of the clinic. Magnetic resonance imaging demonstrated that the spinal cord was draped over the posterior vertebral body of T10. Anterior thoracic spinal cord decompression and fusion were performed through a seventh rib thoracotomy using a structural rib graft to fill the defect. The anterior 1 cm of bone was left intact so as not to cause any additional instability. RESULTS: The patient tolerated the procedure well and had complete resolution of his exertionally dependent myelopathic symptoms. At this writing, 3 years after surgery, he is involved in the Navy ROTC program. CONCLUSIONS: Although Type 2 congenital kyphosis is a rare entity, it should be followed carefully and corrected surgically when appropriate. A history of exertional myelopathy may be an early sign of spinal cord impingement and is an indication for surgical decompression.

Adolescent↗
PubMed2002

Can the thoracic kyphosis be modeled with a simple geometric shape? The results of circular and elliptical modeling in 80 asymptomatic patients.

Many Cobb measurements have been reported at various levels for the thoracic kyphosis, but geometric models of the shape of kyphosis are rare. Thoracic vertebral bodies were digitized on 80 normal lateral full-spine radiographs to obtain the mean thoracic kyphosis. Global and segmental angles were determined. Computer iteration processes passed geometric shapes through the posterior body coordinates of the mean thoracic kyphosis to determine the best fit model in the least squares sense. The kyphosis was closely modeled with ellipses. The T1 and T12 areas tended to be flatter in curvature when compared with T2-T11, indicating these are inflection points. Mean global angles were Cobb(T1-T12) = 44.2 degrees, Cobb(T2-T11) = 39.9 degrees, and Cobb(T3-T10) = 33.3 degrees. The T2-T11 kyphotic region was closely modeled with approximately a 70-degree portion of an ellipse, with minor axis to major axis ratios of 0.6 to 0.72, and with major axis parallel to the posterior body margin of T11.

Adult↗
PubMed2003

Do alterations in vertebral and disc dimensions affect an elliptical model of thoracic kyphosis?

STUDY DESIGN: Mathematical modeling, using least squares method, of thoracic kyphosis was constructed as digitized points from radiographs of 50 healthy patients. OBJECTIVE: To determine a simple geometric model of the thoracic kyphosis. SUMMARY OF BACKGROUND DATA: Thoracic kyphosis is an important parameter of health, but geometric models of kyphosis are rare. Few papers report vertebral body and disc height data. METHODS: Thoracic vertebral bodies were digitized on lateral radiographs of 50 healthy patients. The average path of the posterior vertebral body corners of T1 through T12 was modeled, in the least squares sense, with a portion of an ellipse. The best-fit ellipse was sectioned with different model partitions using four sets of vertebral body heights and disc heights. Segmental and global angles derived from these four models were compared with reported values in the literature. RESULTS: A 72 degrees portion of an ellipse, with a minor-to-major axis ratio of 0.69, can closely approximate the path of the posterior body corners from the inferior of T1 to the superior of T12. The posterior vertebral body heights and disc heights have an average ratio of approximately 5:1. Segmental angles from T3-T4 through T11-T12 for all four models are close to other reported values. The thoracic spine has a height-to-length ratio of approximately 0.96. CONCLUSIONS: Thoracic kyphosis from inferior-posterior T1 to superior-posterior T12 can be closely modeled (least squares error per point < 1 mm) with a 72 degrees piece of an ellipse with a minor-to-major axis ratio of 0.69. The major axis is parallel to the posterior body margin of T12, whereas the minor axis passes through the superior endplate of T12. Segmental angles derived from this elliptical modeling are in the range of values from healthy patients.

Humans↗
PubMed2003

Autogenous tibial strut grafts used in anterior spinal fusion for severe kyphosis and kyphoscoliosis.

STUDY DESIGN: A retrospective review was performed. OBJECTIVE: To evaluate the results of autogenous tibial strut grafts for anterior fusions in children with severe kyphosis and kyphoscoliosis regarding maintenance of correction, clinical outcome, graft fractures, and donor-site morbidity. SUMMARY AND BACKGROUND DATA: Anterior strut grafts harvested from the iliac crest, rib, and fibula often are used to treat severe kyphosis and kyphoscoliosis. Several studies in the literature have observed graft failures, loss of correction, or donor-site morbidity when these grafts have been used. Autogenous tibial strut grafts provide some theoretical advantages with minimal donor-site morbidity. METHODS: This review included 15 patients with severe kyphosis/kyphoscoliosis who underwent anterior spinal fusion with autogenous tibial strut grafts. Among these patients, 13 underwent staged or simultaneous posterior fusions, and 4 underwent cord decompression for myelopathy. An average of seven levels (range, 3-13) were fused anteriorly. Preoperative, postoperative, and latest follow-up radiographs were evaluated for graft incorporation, fracture, hardware failure, and spinal alignment. Patients were examined at the latest follow-up visit, and charts were reviewed to assess neurologic status, back pain, alignment, complications, and donor-site problems. RESULTS: All the patients were available for clinical examination. The mean follow-up period was 3.9 years (range, 2-8 years). The mean kyphosis measured 89 degrees before surgery, 62 degrees after surgery, and 66 degrees at the most recent follow-up assessment. In patients with kyphoscoliosis, the mean coronal curve measured 64 degrees before surgery, 42 degrees after surgery, and 46 degrees at the latest follow-up assessment. Apparent fusion was observed in all cases with no graft fractures. One patient reported mild donor-site discomfort. CONCLUSIONS: Autogenous tibial strut grafts provide physical advantages over commonly used iliac crest, rib, and fibula grafts. The tibia provides dense cortical bone with ample length and mechanical strength, although the actual strength of each strut was not measured directly. In this study, adequate correction was maintained throughout an average follow-up period of 3.9 years, and solid fusion was obtained in all cases. The results indicate that this technique offers a reliable means of providing anterior support in the management of severe kyphosis with virtually no donor-site morbidity. Although the number of patients in this review was limited, the authors believe that anterior autogenous tibial struts are an excellent alternative for the treatment of severe kyphosis and kyphoscoliosis.

Adolescent↗
PubMed2005

Evaluation of spinal fusion using autologous anterior strut grafts and posterior instrumentation for thoracic/thoracolumbar kyphosis.

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: To evaluate anterior strut grafts in spinal fusion for thoracic/thoracolumbar kyphosis. SUMMARY AND BACKGROUND DATA: Autologous strut grafts harvested from the fibula, iliac crest, and rib are frequently used for treating severe kyphosis and kyphoscoliosis. However, a majority of the studies have presented mixed patient populations kyphosis and/or scoliosis, treated either with anterior or anteroposterior fusion. Very few reports have presented an evaluation of autologous strut grafts for anterior fusion with posterior instrumentation for the treatment of kyphotic deformities. METHODS: A total of 23 patients comprised the study. Diagnosis was granulomatous infection (9 patients), congenital (6), posttraumatic (4), neurofibromatosis (1), ankylosing spondylitis (1), Scheuermann disease (1), and plasmacytoma of the vertebral body with pathologic fracture (1). Average age at surgery was 41 years (range 6-77). Indication for surgery was pain with or without progression in 15 patients and additional progressive neurologic deficit in the other 8. Anterior strut grafts consisted of the autologous fibula (9 patients), iliac (10), fibula and ribs (2), fibula and iliac (1), and fibula, iliac, and ribs (1). The fusion areas were thoracic (11 patients), thoracolumbar (11), and cervicothoracic (1). Anterior decompression was performed in 8 patients because of the presence of neurologic symptoms caused by cord compression. Dorsal fusion was performed in all patients with third-generation systems. RESULTS: Average 4.2 vertebrae were fused anteriorly. Mean follow-up bracing time was 9.7 months. Average kyphosis measured 50.9 degrees before surgery and 32.5 at a mean follow-up of 4.5 years (P < 0.0001). No graft breakages were noted at final follow-up. Solid fusion was achieved in all patients. No donor site complications were observed. Of the 8 patients presenting with neurologic deficits, 4 had full recovery, 3 had partial recoveries, and 1 had no improvement. Loss of postoperative correction > 5 degrees was observed in 3 patients. At final follow-up, 3 patients complained of occasional pain, and 1 complained of pain when lying on the back, particularly on hard surfaces. CONCLUSION: Adequate correction was maintained throughout an average follow-up of 4.5 years, and solid fusion was obtained in all patients. Anterior strut grafts, supplemented with posterior fusion with instrumentation provide a good treatment alternative for the treatment of kyphosis deformity of the spine as a result of various etiologies.

Adolescent↗
PubMed2005

Apical lordosating osteotomy and minimal segment fixation for the treatment of thoracic or thoracolumbar osteoporotic kyphosis.

STUDY DESIGN: Retrospective review. OBJECTIVE: To assess the effectiveness of apical lordosating osteotomy (ALO) and minimal segment fixation through a posterior approach for correcting thoracic or thoracolumbar osteoporotic kyphosis (OK). SUMMARY OF BACKGROUND DATA: Current surgical options for OK involve a risk of complex surgery in elderly patients, graft problems (e.g., graft dislodgement, subsidence, pseudarthrosis), and instrumentation problems (e.g., adjacent-segment failure, implant pullout). A posterior-only approach was used to make the surgery less invasive and safer. METHODS: A total of 26 consecutive patients (average age 71.5 years, range 65-81) with thoracic or thoracolumbar OK underwent ALO. Mean follow-up was 3.2 years (range 2.1-6.1). Radiographic studies, complications, and patient satisfaction were assessed. RESULTS: Mean operating time was 137 minutes, and mean blood loss was 717 mL. In 8 patients with thoracic hyperkyphosis, mean Cobb angle was corrected from 82.7 degrees (range 75 degrees-97 degrees) to 25.8 degrees (range 18 degrees-30 degrees), indicating normal kyphosis. In 18 patients, thoracolumbar kyphosis of 56.3 degrees (range 47 degrees-71 degrees) was corrected to -1.8 degrees (range -11 degrees to 7 degrees). Sagittal imbalance was 12.1 cm before surgery and 4.9 cm afterward. Satisfactory correction was achieved in all patients, without anterior release. Local kyphosis was corrected to -9.1 degrees from 53.6 degrees, and mean vertebral kyphosis to -26.6 degrees from 17.7 degrees. In 17 patients with neurologic deficit, Frankel grades improved after surgery. No major complication occurred. All patients had improved pain, self-image, and overall satisfaction. CONCLUSIONS: ALO and minimal segments fixation appear to hold promise for the treatment of thoracic or thoracolumbar OK, and may be safer with fewer complications. A larger series with more patients and surgeons is needed for confirmation.

Aged↗
PubMed2005

Spinal kyphosis causes demyelination and neuronal loss in the spinal cord: a new model of kyphotic deformity using juvenile Japanese small game fowls.

STUDY DESIGN: Histologic changes in the spinal cord caused by progressive spinal kyphosis were assessed using a new animal model. OBJECTIVES: To evaluate the effects of chronic compression associated with kyphotic deformity of the cervical spine on the spinal cord. SUMMARY OF BACKGROUND DATA: The spinal cord has remarkable ability to resist chronic compression, however, delayed paralysis is sometimes seen following the development of spinal kyphosis. In the past, no animal model to clarify the mechanism of spinal cord damage due to spinal kyphotic deformity has been available. METHODS: Laminectomy and bilateral facetectomy at the C4-C5 level was performed in 52 Japanese small game fowls. Histologic changes in the spinal cord associated with progressive kyphotic deformity were examined at different time points after surgery in each animal. The degree of spinal cord flattening and the severity of demyelination in histologic sections were quantitatively evaluated using an image analyzer, and their association with the kyphotic angle was analyzed. Changes in the microvascular distribution in the spinal cord were also examined by microangiography. RESULTS: In all operated animals, progressive kyphosis developed reproducibly. The kyphotic angle increased gradually until 3 weeks after surgery and stabilized thereafter. There was a significant correlation between the kyphotic angle and the degree of spinal cord flattening. The spinal cord was compressed most intensely at the apex of the kyphosis, where demyelination of the anterior funiculus as well as neuronal loss and atrophy of the anterior horn were observed. Demyelination progressed as the kyphotic deformity became more severe, initially affecting the anterior funiculus and later extending to the lateral and then the posterior funiculus. Angiography revealed a decrease of the vascular distribution at the ventral side of the compressed spinal cord. CONCLUSIONS: Progressive kyphosis of the cervical spine resulted in demyelination of nerve fibers in the funiculi and neuronal loss in the anterior horn due tochronic compression of the spinal cord. These histologic changes seem to be associated with both continuous mechanical compression and vascular changes in the spinal cord.

Animals↗
PubMed2006

Kyphoplasty reduction of osteoporotic vertebral compression fractures: correction of local kyphosis versus overall sagittal alignment.

STUDY DESIGN: A retrospective study of patients who underwent 1-3-level kyphoplasty procedures at a single institute. OBJECTIVE: To examine and compare the effects of single and multilevel kyphoplasty procedures on local versus overall sagittal alignment of the spine. SUMMARY OF BACKGROUND DATA: Cement augmentation has been a safe and effective method in the treatment of symptomatic vertebral compression fractures (VCFs). In addition to providing rapid pain relief, balloon tamp kyphoplasty has reduced acute fractures, allowed controlled cement placement under lower pressure, and resulted in improvement of deformity. The restoration of normal overall spinal sagittal alignment in the elderly patient with a VCF and kyphotic deformity has obvious benefits. Although significant correction of local kyphosis (fractured vertebra) has been reported in the literature, to our knowledge, there have been no reports on whether this leads to an improved overall sagittal alignment. METHODS: A total of 65 consecutive patients with symptomatic VCFs who underwent 1-3-level kyphoplasty procedures were included in the study. Preoperative and postoperative radiographs were analyzed to quantify local and overall spinal sagittal alignment correction. Preoperative and postoperative vertebral heights at the fractured levels were also measured and categorized into anterior, middle, or posterior vertebral heights. RESULTS: Measurements revealed that kyphoplasty reduced local kyphotic deformity at the fractured vertebra by an average of 7.3 degrees (63% of preoperative kyphosis). This result did not translate to similar correction in overall sagittal alignment. In fact, angular correction decreased to 2.4 degrees (20% of preoperative kyphosis at fractured level) when measured 1 level above and below. The angular correction further decreased to 1.5 degrees and 1.0 degrees (13% and 8% of preoperative kyphosis at fractured level), respectively, at spans of 2 and 3 levels above and below. Average height gain was highest in the middle of the vertebral body (39% increase) compared to the anterior or posterior edges (19% and 3% increases, respectively). With multilevel kyphoplasty procedures, higher angular gains were seen over more vertebrae compared to the 7.3 degrees for a single-level kyphoplasty: 7.8 degrees over 2 levels and 7.7 degrees over 3 levels for 2 and 3-level kyphoplasty procedures, respectively. Kyphoplasty was able to achieve higher angular reduction in thoracic versus lumbar fractures (8.5 vs. 6.4 degrees, P < 0.01). The angular correction was also better maintained over adjacent segments in the thoracic spine. CONCLUSION: The majority of kyphosis correction by kyphoplasty is limited to the vertebral body treated. The majority of height gained after kyphoplasty occurs in the midbody. Higher correction over longer spans of the spine can be achieved with multilevel kyphoplasty procedures, in proportion to the number of levels addressed. Notwithstanding its well-published clinical efficacy, it is unrealistic to expect a 1 or 2-level kyphoplasty to improve significantly the overall sagittal alignment after VCFs.

Aged↗
PubMed1983

Radiographic determination of lordosis and kyphosis in normal and scoliotic children.

We conducted a radiographic retrospective study in children to determine spinal lordosis and kyphosis. A total of 218 lateral standing full-length radiographs were studied: 104 normal and 114 scoliotic patients. Normal X-ray films were defined as those obtained for suspected disorder (e.g., scoliosis) with no abnormalities detected by the radiologist or orthopedist. Thoracic kyphosis is defined as the angle between perpendiculars drawn from the inferior endplate of T5 and the superior endplate of T12. Lordosis is the angle between perpendiculars from the inferior endplate of L1 and the superior endplate of L5. The angle between the inferior endplate of L5 and the top of the sacrum is the L5-S1 angle. Statistical analysis was undertaken to compare lordosis and kyphosis radiographic measurements with age, sex, height, and weight employing the SAS package program. No significant relationships were noted between degree of scoliosis, age, sex, height or weight, and kyphosis, lordosis, or L5-S1 angle. Neither could correlations among the three radiographic measurements be made. Lordosis measured 40 degrees (range 31-49.5 degrees) in normal and 48.5 degrees (range 40-55 degrees) in scoliotic patients. Kyphosis measured 27 degrees (range 21-33 degrees) in normal and 28 degrees (range 16.5-36 degrees) in scoliotic patients.

Adolescent↗
PubMed1996

Development of pathological lumbar kyphosis in myelomeningocele.

We analysed the cases of lumbar kyphosis in 151 (21%) of a series of 719 patients with myelomeningocele. Three different types were distinguished: paralytic, sharp-angled and congenital. In a cross-sectional and partly longitudinal study the size and magnitude of the kyphosis, the apex of the curve and the level of paralysis of each group were recorded and statistically analysed. Paralytic kyphosis (less than 90 degrees at birth) occurred in 44.4% and increased linearly during further development. Sharp-angled kyphosis (90 degrees or more at birth) was present in 38.4% and also showed a linear progression. In both types, progression seemed to depend also on the level of paralysis. Congenital kyphosis occurred in 13.9% and we could find no significant factor which correlated with progression.

Cross-Sectional Studies↗
PubMed1993

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.

Activities of Daily Living↗
PubMed1983

Progression of congenital kyphosis in Ishibashi rats.

The development of congenital kyphosis was studied radiographically and histologically in 32 female and 34 male Ishibashi rats between the fourth and thirty-sixth week after birth. The major congenital spinal anomalies were defects of segmentation in the lumbar area. The malformation was classified into four groups according to the state of non-segmentation seen in radiographs. The progression of kyphosis was closely related to various changes at intervertebral spaces. The spinal deformity resulting from narrowing of the intervertebral spaces without bony fusion did not progress with growth, and the epiphyseal plates remained relatively intact unrelated to the existence of disc tissue. The deformity resulting from ventral bony fusion without radiographic bony anomalies showed histologically dysplastic epiphyseal plates on the ventral side. Progression of the kyphosis occurred in this type of deformity. The kyphosis resulting from bony fusion and ventral wedge-vertebrae progressed in the males. Progressive kyphosis appeared to be due to a difference in growth potential between the ventral and dorsal epiphyseal plates.

Animals↗
PubMed1999

Restoration of thoracic kyphosis in the hypokyphotic spine: a comparison between multiple-hook and segmental pedicle screw fixation in adolescent idiopathic scoliosis.

This study verified the efficacy of segmental pedicle screw fixation in restoring thoracic kyphosis in persons with hypokyphotic scoliosis. Fifty-one patients were divided into three groups by the degree of preoperative thoracic hypokyphosis and fixation method used: the hypokyphosis-hook (HH), hypokyphosis-screw (HS), and normal kyphosis-screw (NS) group. They were compared after a minimum follow-up period of 2 years. Preoperative thoracic kyphosis of 4.1 degrees +/- 8.6 degrees, 8.1 degrees +/- 5.6 degrees and 27.3 degrees +/- 9.8 degrees in the HH, HS, and NS groups were restored to 14.5 degrees +/- 10.2 degrees, 27.3 degrees +/- 11.3 degrees, and 28.3 degrees +/- 13.7 degrees, respectively. The difference between the HH and HS groups was significant (p = 0.000). The HS and the NS groups did not differ (p = 0.16). This indicates that segmental pedicle screw fixation was more effective than multiple hooks in restoring kyphosis in patients with hypokyphotic scoliosis and created kyphosis similar to that in patients without preoperative hypokyphosis.

Adolescent↗
PubMed2005

[Surgical correction of post-traumatic kyphosis of thoracolumbar spine].

OBJECTIVE: To determine the effectiveness of surgical correction for post-traumatic kyphosis of thoracolumbar spine. METHODS: From 1996 to 2003, 33 consecutive patients with post-traumatic kyphosis of thoracolumbar spine were corrected surgically. The mean age was 40.3 years (range, 13 - 65 years). The mean time between the initial injury and surgical correction was 36.0 months (range, 6 - 220 months). The kyphotic deformity averaged 40.8 degrees (range, 20 degrees - 82 degrees ). All the patients had neurological deficits. Twelve patients had obvious back pain. Seven patients lost sphincter function completely and nineteen patients lost the function partly. Twenty-three patients had ever undergone laminectomy and/or instrumentation. The treatment procedure consisted of anterior release and posterior spinal osteotomy with instrumentation (15 patients), posterior closing wedge osteotomy with instrumentation (12 patients), anterior release and instrumentation (6 patients). RESULTS: Kyphosis was corrected from an average of 40.8 degrees to an average of 5.7 degrees, the corrective rate was 86.0% (40.8 degrees - 5.7 degrees /40.8 degrees). There were no severe complications. The average follow-up period was 24.6 months (range, 6 - 84 months). There was no loss of correction at follow-up. Ten of these patients showed an improvement in neural function by one or two levels according to the classification. Sphincter function recovered partly in ten patients. Back pain was relieved significantly in all of twelve patients with back pain preoperatively. Bony fusion was achieved in thirty-two patients. One patient had nonunion and achieved bony fusion after revision. CONCLUSION: Posterior closing wedge osteotomy was suitable to kyphosis less than 40 degrees. Anterior release and posterior spinal osteotomy was effective, especially to the patients with severe kyphosis deformity or with operation history. Patients with incomplete neurological deficits and/or severe back pain could get benefit from osteotomy of spine, even if their medical history was long.

Adolescent↗
PubMed1990

Measurement of scoliosis and kyphosis radiographs. Intraobserver and interobserver variation.

Interobserver variations for measurements of the Cobb angle on radiographs of patients who had kyphosis were comparable with those on the radiographs of patients who had scoliosis. Four staff orthopaedists and one physical therapist measured eight radiographs that showed scoliosis and twenty that showed kyphosis. The measurements were made on two occasions and in random order. For scoliosis, the average difference between readings was 3.8 degrees, and 95 per cent of the differences were 8 degrees or less (range, 0 to 10 degrees). These findings were in keeping with those of other published reports. For kyphosis, the average difference between readings was 3.3 degrees, and 95 per cent of the differences were 7 degrees or less (range, 0 to 30 degrees). One investigator rated the kyphosis radiographs with respect to clarity. There was a trend to less variation with clearer radiographs, but this was not significant. The end-vertebrae were pre-selected for some radiographs and were freely chosen by the interpreter for others. Reliability was not significantly improved when the end-vertebrae of the curve had been pre-selected. Using the statistical method called tolerance limits, we determined that if one were to be 95 per cent confident that a measured difference represented a true change, the difference would have to be 10 degrees for scoliosis radiographs and 11 degrees for kyphosis radiographs. The probability that a measured difference is due to measurement error alone (that is, a false-positive reading) was calculated.

Analysis of Variance↗
PubMed1987

Relationship of kyphosis to physical fitness and bone mass on post-menopausal women.

Kyphosis is commonly associated with ageing and osteoporosis of the spine. This study was conducted to evaluate whether physical fitness and bone mass in post menopausal women, between the ages of 50-60 years, may influence the degree of kyphosis. The level of physical fitness was determined by 1) calculating maximum oxygen uptake, (VO2 max), attained by a graded exercise treadmill test, and 2) evaluating the muscle strength in performing one repetition maximum on the bench press. In vivo neutron activation analysis was used to measure the bone mineral content in the axial skeleton and proximal femurs. It is expressed as Calcium Bone Index (CaBI). The normal range was 1.00 +/- 0.12 (I.S.D.). The degree of kyphosis was measured indirectly by calculation of an index of kyphosis, (I/K), using a surveyor's flexicurve. Individuals with I/K greater than 13 showed a clinically apparent kyphosis. Fit individuals (VO2 max greater than 29 ml/kg/min) had a significantly lower I/K (p less than 0.001) than average persons. Individuals with normal bone mass (CaBI greater than 0.8) also had a significantly lower I/K (p less than 0.05) than those with bone loss. Similarly, subjects who were fit, and had normal bone mass, had a significantly lower I/K (p less than 0.001) than those who were less fit and had bone loss. There was a significant correlation between I/K and VO2 max (p less than 0.02, df 45), I/K and CaBI (p less than 0.05, df 45) and I/K and bench press (p less than 0.05, df 45).(ABSTRACT TRUNCATED AT 250 WORDS)

Bone and Bones↗