Left handedness and risk of thoracic hyperkyphosis in prepubertal schoolchildren.

BACKGROUND: Hand dominance and spinal posture were studied for their prediction of the development of thoracic hyperkyphosis during the pubertal growth spurt. METHODS: The cohort consisted of all the fourth-grade school children of the Western School District of Helsinki, Finland, in the spring of 1986. They were examined annually from the mean age of 10.8 to 13.8 years. Handedness was determined at the baseline examination by observing the hand with which the child was writing. Anthropometric measurements, posture and growth were followed-up annually. A lateral standing radiograph was undertaken in those children who had pronounced thoracic kyphosis in spinal pantography. Kyphotic angles > or = 45 degrees were considered hyperkyphotic. RESULTS: In both girls and boys, left handedness was found to be a powerful determinant of hyperkyphosis. In left handed children the odds ratio (OR), adjusted for baseline spinal measurements, was 4.11 (95% confidence interval [CI]: 1.39-12.13). Hump size measured by the forward bending test also predicted significantly the development of thoracic hyperkyphosis (OR = 1.48; 95% CI: 1.23-1.76, per one degree). CONCLUSIONS: Left handedness may be a risk factor for thoracic hyperkyphosis during the pubertal growth spurt.

Spinal mobility and posture in 8- to 16-year-old children.

Spinal mobility and posture were measured in 294 8-16-year-old boys and girls, divided into five age groups. The upper thoracic sagittal alignment was more vertical among girls, but the postural curves showed no significant age-related differences for either sex. Among both boys and girls thoracic extension, lateral flexion, and rotation decreased significantly between the ages of 12 and 13, but with the exception of extension they returned to the previous level by age 16. Girls were significantly different from boys at 13 years of age. In the thoracic spine, girls had less kyphosis, and were stiffer in forward and lateral flexion, with more rotation to the right than to the left. In the lumbar spine, lateral flexion increased after the age of 10 in both sexes. Between the ages of 8 and 14 lumbar lateral flexion was significantly greater among girls than among boys, whereas extension and rotation was greater only at the ages of 8 and 10 years. With increasing age, a shift from left to right dominance in lumbar lateral flexion was found in girls only.

Spinal mobility and posture in adolescent idiopathic scoliosis at three stages of curve magnitude.

Spinal posture and mobility were studied in 71 girls with progressive adolescent idiopathic thoracic scoliosis. Measurements were carried out by inclinometers and a compass in three planes; sagittal, frontal, and horizontal. The patients were divided into three groups according to the curve magnitude. Group 1 had curves smaller than 25 degrees, group 2 had curves between 25 and 35 degrees, and group 3 had curves greater than 35 degrees. The positional inclines of sacrum, upper lumbar and upper thoracic areas became more vertical as the curve size increased resulting in smaller lumbar lordosis and thoracic kyphosis. In the thoracic spine flexion and bending to the right was smaller in group 3 than in the other groups. Rotations in both clockwise and counterclockwise directions decreased as the curve size increased. In the lumbar spine only bending to the left decreased significantly with the curve size increase. All thoracic and lumbar movements except lumbar rotations had a general tendency to stiffening as the curve size increased. Of the mobility measurements thoracic rotation most clearly decreased with increased curves, which together with straightening of the spine can be important features in the pathomechanism of a progressive idiopathic thoracic curve.

Spinal mobility and posture and their correlations with growth velocity in structurally normal boys and girls aged 13 to 14.

Spinal mobility and posture were measured and their correlations with growth velocity were calculated in 30 boys and 30 girls aged 13 to 14. The spinal measurements were carried out by noninvasive goniometric methods. In the thoracic spine kyphosis (P less than 0.01), forward flexion (P less than 0.01) and the sum of lateral flexions (P less than 0.05) were reduced in the girls compared with the boys. In the boys and girls alike, thoracic rotation to the left was smaller than to the right, but the difference was statistically significant (P less than 0.05) only for the girls. In the girls, thoracic forward flexion and rotation to the left had negative correlations (r = -0.38 and -0.39, P less than 0.05) with growth velocity. The hypothetical significance of the results for the explanation of the development of adolescent idiopathic scoliosis is discussed.

Scoliosis associated with lumbar spondylolisthesis. A clinical survey of 190 young patients.

A series of 190 patients with lumbar spondylolisthesis treated operatively during the years 1948-80 at the mean age of 15.2 years (8-19 years) and reexamined 4-36 years (mean 11.2 years) later are presented. In 92 of them (48%) scoliosis (more than 5 degrees) in association with olisthesis was seen. The slipping affected the fifth segment in 90 and fourth segment in two patients. The female predominance was characteristic in the scoliotic group. Dysplastic changes of the posterior arc were more often seen in the group of patients with scoliosis than in the nonscoliotic group, and they also presented a more severe grade of slipping and lumbosacral kyphosis. The curve was usually mild and was situated in the lumbar area. Patients with a higher degree of lumbosacral kyphosis and more severe slipping also had a statistically higher degree of lumbar scoliosis. Operative treatment of spondylolisthesis consisted of posterior or posterolateral fusion in situ, but two patients were treated using ventral fusion and three severe cases with removal of loose posterior element. Lumbar scoliosis classified as sciatic type disappeared in 25 out of 39 patients after lumbosacral fusion, suggesting the "sciatic muscle spasm" as an etiologic factor. The torsional type of curve resulting from asymmetrical slipping of the vertebra was also corrected in 19 out of 28 cases after fusion. At follow-up patients with remaining lumbar scoliosis represented more low-back pain than those without any curve. In our opinion lumbosacral fusion is indicated before lumbar curve changes to structural scoliosis in symptomatic patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Scoliosis in patients with diastrophic dysplasia: a new classification.

STUDY DESIGN: Scoliosis in patients with diastrophic dysplasia was analyzed. OBJECTIVES: To study the natural history of scoliosis and to classify the patients with different types of scoliosis. SUMMARY OF BACKGROUND DATA: Typical findings in diastrophic dysplasia are short-limbed short stature, multiple joint contractures, early degeneration of joints, and spinal deformities. The largest studies have reported scoliosis in 37% to 88% of the patients with this rare skeletal dysplasia. The natural history of the deformity is unknown. METHODS: Of the 130 unselected patients, 98 (75%) who were older than 16 years and/or had undergone surgery at the time of the last radiograph were included in the final analysis. These 98 patients included 37 males and 61 females. Their ages at the first radiograph ranged from newborn to 78 years (average, 21 years). The mean follow-up period was 20 years (range, 2-41 years) for 80 patients. Standard standing anteroposterior and lateral radiographs were taken. The degrees of scoliosis, kyphosis, and lordosis were measured according to the Cobb method. Classification of the scoliosis was based on the patient's age at onset of scoliosis, the rate of progression, the magnitude of the scoliosis at the end of growth, and the curve pattern. RESULTS: Of the 98 patients in this study, 86 (88%) had scoliosis. This difference was highly significant statistically (P < 0.001), as compared with the normal population. The frequency of scoliosis was 90% among females and 84% among males. Scoliosis can be divided further into three subtypes: early progressive (11 patients), idiopathic-like (41 patients), and mild nonprogressive (33 patients). One patient had a congenital scoliosis. CONCLUSIONS: Scoliosis is very common in patients with diastrophic dysplasia. The natural history of scoliosis varies from severe deformity with rapid progression to mild deformity without any progression. The authors suggest that the classification described in this report offers a tool for the predicting natural history of scoliosis in diastrophic dysplasia, and for adjusting the timing of surgery in individual patients.

Spinal mobility in adolescent girls with idiopathic scoliosis and in structurally normal controls.

Spinal mobility and posture were studied in 29 adolescent girls (mean age, 13.9 years) with thoracal idiopathic scoliosis, and in 30 healthy girls (mean age, 14.0 years) of the same age. Measurements of the mobility were conducted by inclinometers and a compass in three planes; sagittal, frontal, and horizontal. The structurally healthy girls were taller and heavier than the scoliotics; the difference was statistically significant for weight (P less than 0.01). The positional inclines of sacrum, upper lumbar and thoracic areas were significantly smaller in the scoliotics, resulting in smaller lumbar lordosis and thoracic kyphosis in them (P less than 0.001). In the thoracic spine, forward flexion was smaller (P less than 0.01), whereas extension (P less than 0.001) and the total sagittal mobility (P less than 0.01) were greater in the scoliotics. In the healthy controls, the thoracic clockwise rotation was significantly (P less than 0.05) larger than the counterclockwise. This side difference had disappeared in the scoliotics, and their total thoracic rotation was indicatively smaller than in the controls. In the lumbar spine, extension was smaller (P less than 0.01) in the scoliotics than in the controls. All spinal mobility measurements noted there was no change of general spinal flexibility in the scoliotics.

Trunk asymmetry, posture, growth, and risk of scoliosis. A three-year follow-up of Finnish prepubertal school children.

Several anthropometric measurements were studied for their prediction of scoliosis in 896 children (430 girls and 466 boys) who were free from scoliosis at entry. The children were examined annually from the average age of 10.8 to 13.8 years to follow up their trunk asymmetry, posture, and growth. Scoliosis developed in 24 boys and 41 girls (Cobb angle > or = 10 degrees in a posteroanterior standing radiograph) during the 3 years. In both girls and boys, trunk asymmetry measured by the forward bending test was found to be the most powerful determinant of the incidence of scoliosis. In the whole cohort the adjusted odds ratio was 1.61 and its 95% confidence interval was 1.42-1.82 per one millimeter increase in trunk hump. Using spinal pantography the degree of thoracic kyphosis in girls (odds ratio = 1.05, 95% confidence interval = 1.01-1.09, per one degree) and the degree of lumbar lordosis in boys (odds ratio = 1.07, 95% confidence interval = 1.01-1.13, per one degree) were significant predictors of future scoliosis. In the children both sexes who eventually had scoliosis, body height, sitting height, and growth of sitting height were greater than in other children, but these factors carried no statistical significance in the logistic analyses. There were differences between the prescoliotic girls and other girls in both mean age (11.8 vs 12.1 years, P = 0.02) and value (5.5 cm vs 6.1 cm/yr, P = 0.08) of peak sitting height velocity.(ABSTRACT TRUNCATED AT 250 WORDS)

Thoracic and lumbar spine in diastrophic dysplasia: a clinical and magnetic resonance imaging analysis.

STUDY DESIGN: Cross-sectional study to evaluate the thoracic and lumbar spine in patients with diastrophic dysplasia (DD). OBJECTIVES: To find the causative factors behind the spinal deformities and restricted mobility of the spine. SUMMARY OF BACKGROUND DATA: Typical findings in this skeletal dysplasia are short-limbed stature, multiple joint contractures, early degeneration of joints, and spinal deformities such as cervical kyphosis, scoliosis, and exaggerated lumbar lordosis. The pathogenic mechanism of scoliosis is unknown. METHODS: A physical examination was performed on 88 patients (55 females, 33 males) with an average age of 31 years (range, 3-56). Magnetic resonance (MR) images from T2 to S1 and radiographs were obtained. Degree of scoliosis was measured according to Cobb from standing radiographs. The anatomy of the medulla and the size of the spinal canal were assessed. The transverse dural tube area was measured from L2 to S1. Disc space, degeneration, and protrusions were evaluated. Vertebral abnormalities, if any, facet joint degeneration and the state of the spinal muscles were also assessed. RESULTS: Physical examination showed diminished mobility of the spine. Scoliosis was noted in 70 patients with an average of 42 degrees (range, 11-188 degrees ). The mean transverse area of the dural tube ranged from 94 mm(2) at L2-L3 to 57 mm(2) at L5-S1. The area was smaller at all levels compared with reference values (P < 0.001). One patient had severe thoracic and lumbar spinal stenosis. Five patients had compression of neural structures in the lumbar spinal canal in MR images, but had no clinical symptoms. All patients exhibited narrowed disc heights and a decrease in the signal intensity of discs on T2-weighted images. The prevalence of disc protrusions was low; three patients had a prolapse in the lumbar spine. Two patients displayed vertebral anomalies. All patients also had muscular atrophy and degenerative-like facet joint hypertrophy. The severity of these changes increased with age. CONCLUSIONS: Abnormal disc structure and rapid degeneration explain the diminished decreased mobility of the spine and may be a causative factor in the development of scoliosis. Muscular atrophy may be caused by reduced physical activity and rigid spinal deformities. The spinal canal is narrowed, but symptomatic lumbar spinal stenosis is uncommon.

Anthropometric measurements and the incidence of low back pain in a cohort of pubertal children.

STUDY DESIGN: The authors studied the anthropometric measurements to predict low back pain (LBP) in a cohort of growing adolescents. SUMMARY OF BACKGROUND DATA: The cohort consisted of all the fourth-grade school children of the western school district of Helsinki, Finland, in the spring of 1986. They were examined annually from the mean age of 11.8 to 13.8 years. METHODS: The forward bending test, measurements of total arm length, pelvic equilibrium, and spinal pantographs were carried out by the same physiatrist. A standardized pain questionnaire presented at the final examination obtained the history of LBP. Of the original cohort of 1060 children, those 859 (408 girls and 451 boys) who participated in all the examinations and had not had LBP until the age of 12.8 years were included in this study. RESULTS: The 1-year (from 12.8 to 13.8 years) incidence of LBP was 18.4% in girls and 16.9% in boys. Trunk asymmetry measured by the forward bending test and sitting height were significant determinants of the incidence of LBP. In the whole cohort, the odds ratio (OR) of trunk asymmetry adjusted for all the other risk determinants was 1.19 and its confidence interval (CI) was 1.00-1.39 per one standard deviation increase of the trunk hump. In the multivariate analysis comprising both sexes, OR per one standard deviation increase of sitting height was 1.24, (95% CI 1.03-1.46). In boys, standing height (OR 1.40, 95% CI 1.13-1.65, per one standard deviation) and sitting height (OR 1.35, 95% CI 1.09-1.63, per one standard deviation) were positively associated with the risk of LBP. These associations were not significant in girls. CONCLUSIONS: Sitting height and trunk asymmetry may contribute to LBP in pubertal children. The role of anthropometric characteristics seems, however, modest.

The spine in diastrophic dysplasia.

Diastrophic dysplasia is an autosomal recessive disorder of the skeleton, characterized by disproportionate short stature, generalized joint deformities, club feet, deformed ear pinnae, and, frequently, spinal deformity and cleft palate. Diastrophic dysplasia is more common in Finland than elsewhere. We studied 101 patients with an age range from newborns to 79 years to find out the frequency and type of spinal deformities, the early signs of progressive cases, and to follow the natural history of the disease. In the follow-up study, 17 patients were under 10 years, 21 under 21 years, and 63 over 21 years of age. One-third of the patients had cervical kyphosis; in the most severe case the kyphosis was 180 degrees and led to quadriplegia during anesthesia. In three patients, cervical kyphosis resolved spontaneously before the age of 5 years. The overall frequency of scoliosis was 37%; 49% in women and 22% in men. Only 13 patients had curves greater than 50 degrees; these curves constituted distinct rotation at the apex from the early evolution of the curve. The early signs of severe curves were detectable at the age of 2 to 4 years. Only two patients were operated on because of scoliosis; one with fusion in situ and the other instrumented with the pediatric Cotrel-Dubousset instrumentation. Three patients had a brace, which did not prevent the progression of the curve. Symptoms referring to a narrow spinal canal were registered in four patients, two of which were operated on; a lumbar posterior decompressive procedure was made at adult age.

Cervical kyphosis in diastrophic dysplasia.

STUDY DESIGN: An evaluation of cervical kyphosis in diastrophic dysplasia from newborn to adult life. OBJECTIVES: To discover the prevalence and natural history of cervical kyphosis in diastrophic dysplasia. SUMMARY OF BACKGROUND DATA: Typical findings in this rare skeletal dysplasia are sport-limbed short stature, multiple joint contractures, early degeneration of joints, and spinal deformities such as cervical kyphosis, scoliosis, and exaggerated lumbar lordosis. In diastrophic dysplasia, spontaneous resolution of cervical kyphosis has been reported, but so have severe forms causing medullar compression leading to quadriplegia and death. The prevalence and clinical outcome of the kyphosis are not known. METHODS: The radiographic natural history of the cervical spine was studied in 120 patients. They varied in age from newborns to 63-year-olds. The average follow-up time in 26 living patients with cervical kyphosis was 10.0 years. RESULTS: Midcervical kyphosis was noted in 29 patients (24%) in their first radiograph. In 25 patients, the first radiographs were taken before the age of 18 months, and 24 of these patients (96%) had cervical kyphosis. The most severe case was that of a 32-year-old patient with a 165 degrees kyphosis. In the 24 patients, the kyphosis resolved spontaneously at an average age of 7.1 years. Three patients with a severe kyphosis died; one patient is alive. One patient, a 4-year-old child has mild resolving deformity. CONCLUSIONS: Cervical kyphosis in diastrophic dysplasia usually is shown at the time of birth. It resolves spontaneously during growth and seldom needs treatment. Careful follow-up study and treatment, if necessary, are important tools for avoiding the neurologic problems and fatal outcome.

Lumbar isthmic spondylolisthesis in children and adolescents. Radiologic evaluation and results of operative treatment.

A clinical and radiologic follow-up study of a group of 75 children and adolescents, comprised of both boys and girls, who underwent spondylodesis for spondylolisthesis between the years 1979 and 1984 is reported. Sagittal rotation, lumbosacral joint angle, lumbar lordosis, wedging of olisthetic vertebrae, and the rounding of the upper sacrum showed considerable statistical correlation to the amount of slipping and accordingly should be noted when estimating the risk of progression of the spondylolisthesis. When the spondylolisthesis was accompanied by scoliosis, it was noted that seriousness of the former was closely correlated to that of the latter. Most patients profited by the operation, and solid fusion was achieved in almost all cases. The posterolateral spondylolysis performed using graft from the iliac crest, the interbody fusion technique, or their combination turned out to be the most reliable surgical methods. The combined technique was especially required in cases with a high degree of slipping.

Progression of spondylolisthesis in children and adolescents. A long-term follow-up of 272 patients.

The radiologic progression of spondylolisthesis during a long-term follow-up was studied in 272 children and adolescents. There were 134 girls and 138 boys. The mean age at the first visit was 14.3 years (girls, 13.8 years; boys, 14.9 years). The radiologic follow-up time was 14.8 years on average (range, 5-32). The operation was done in 190 patients younger than 20 years of age. Fusion in situ, using a posterior or posterolateral technique, had no statistically significant effect on progression. Surgically treated patients did not differ from conservatively treated patients. Ninety percent of the slip, on average, had already occurred at the first radiologic examination compared with the final amount of slip. More than 10% progression occurred in 62 patients, mainly within the first year postoperatively or after the first examination. Progression of the lumbosacral kyphosis and sinking of the vertebral body was noted in severe slips. Although female gender and dysplasia (spina bifida) at the lumbosacral junction were more frequent in severe slips, they statistically had no value in predicting progression. A wedge form of L5 or sacral rounding also had no prognostic value. These were secondary to the slip and expressed it but did not predict it. The only radiologic variable with predictive value of progression was the percentage amount of the primary slip. In age groups corresponding to the growth spurt in early puberty (girls, 9-12 years; boys, 11-14 years), there was a tendency to progress.

Surgical treatment of severe isthmic spondylolisthesis in adolescents. Reduction or fusion in situ.

Twenty-two adolescent patients with severe (more than 50%) slip were surgically treated. Eleven were reduced with Magerl/Dick transpedicular screw devices and fused posteriorly from L4 to S1, and 2 weeks later anteriorly L5-S1; the other 11 were fused in situ L4-S1 (6 patients) or L5-S1 (5 patients) using a circumferential (6 patients), anterior (4 patients) or posterolateral (1 patient) technique without instrumentation. The two groups were comparable as to age at operation, age at follow-up, follow-up time, and preoperative radiologic measurement of the slip, lumbosacral kyphosis, and clinical findings. The mean follow-up times were 56.5 and 59.8 months, respectively. In the reduction group an improvement in the slip of 36.1 percentage points was achieved as compared with 7.7 percentage points in the in situ-fusion group. The sagittal rotation angle improved by 11 in the reduction group and worsened by 2.8 in the in situ-fusion group. There were no differences between the groups in the functional tests or clinical findings concerning pain. Subjective assessment was good in both groups at follow-up; that is, the pain had disappeared. Mean operation time and intraoperative blood loss were significantly higher in the reduction group. Reduction procedures were also associated with a higher number of complications and reoperations. No neurologic complications, however, occurred in the reduction group. Based on this study, in situ fusions are to be preferred in adolescents with severe spondylolisthesis.

Development of trunk asymmetry in a cohort of children ages 11 to 22 years.

STUDY DESIGN: A cohort study with a follow-up period of 11 years. OBJECTIVES: To study the growth of the spine with a focus on the development of trunk asymmetry and scoliosis. SUMMARY OF BACKGROUND DATA: Trunk asymmetry, a common phenomenon at adolescence, can be considered the clinical expression of scoliosis. The importance of the pubertal growth spurt has been stressed in the natural history of scoliosis. However, no cohort studies have focused on the ascending and descending phase of the spine's peak growth and the development of trunk asymmetry. METHODS: The cohort consisted of all the fourth-grade school children in the Western school district of Helsinki, Finland, in the spring of 1986. These 1060 children (515 girls and 545 boys), from the average age of 11 to 14 years, were invited to undergo annual examinations. The 855 children (80.7%) who had participated in the study at the age of 14 years were invited to a reexamination at the age of 22 years. This invitation was accepted by 430 (208 women and 222 men; 54%) of those invited. The forward bending test, the spinal pantography, and the anthropometric measurements were carried out by the same author (M.N.) throughout this study. RESULTS: At 22 years of age, 30% of the adults were found to be symmetric, with a hump less than 4 mm in the forward bending test, whereas 51% had a hump of 4 to 9 mm, and 19% had a hump 10 mm or larger (major asymmetry). The directional asymmetry of trunk surface, a skew to the right at the thoracic level and to the left at the lumbar level at puberty, remained constant at adult age. The prevalence of major trunk asymmetry at adult age was the same in both women and men, in contrast to the female predominance at puberty in this cohort. There were close correlations in the degrees of thoracic and lumbar asymmetry between puberty and adult ages. CONCLUSIONS: The shape of the back develops mainly during the pubertal growth spurt at ages 12 to 14 years in girls and boys. Trunk asymmetry (and mild scoliosis) seems as prevalent in young adult women as in men, although at puberty idiopathic scoliosis was twice as prevalent among girls as among boys in this cohort.

Foot deformities in diastrophic dysplasia. An analysis of 102 patients.

The exceptionally high prevalence of diastrophic dysplasia in Finland has enabled us to analyse the foot deformities of 102 patients at their first orthopaedic evaluation and classify 204 feet into five categories. The most common finding (43%) was a foot with tarsal valgus deformity and metatarsus adductus; 37% showed either equinovarus adductus (29%) or equinus (8%) deformities. At the first examination 13% showed metatarsus adductus deformity alone, and 7% were clinically normal. The expression 'club foot', generally used for the foot deformity in diastrophic dysplasia is a misnomer. There is a wide spectrum of deformities, some of them specific for the condition.

The knee joint in diastrophic dysplasia. A clinical and radiological study.

We examined clinically and radiologically the knees of 46 patients (27 females and 19 males) with diastrophic dysplasia. The age of the patients varied from newborn to 38 years. A total of 18 patients was followed during their growth until adolescence. The knees of two legally aborted fetuses appeared on examination to be macroscopically normal and congruous. Excessive valgus deformity of the tibiofemoral weight-bearing angle with a mean of 14 degrees was noted in infancy. Most of the patients had marked instability of the knees. The range of movement of the knee began to decrease before the age of five years. There were signs of early degeneration and deformation of the bony epiphyses before the age of six years. The patellofemoral joint was abnormal from an early age. A marked patella infera, often associated with a lateral position of the patella with bony fragmentation, was noted. The knee in diastrophic dysplasia is basically unstable, showing early deformation of the subchondral bone and degeneration of the joint.

Severe spondylolisthesis in children and adolescents. A long-term review of fusion in situ.

From 1948 to 1980, 93 children and adolescents had fusion in situ for severe spondylolisthesis with a slip of 50% or more, at a mean age of 14.8 years. Of these, 52 girls and 35 boys were reviewed after a mean follow-up of 13.8 years. The mean pre-operative slip was 76% and pain frequency correlated with the severity of the lumbosacral kyphosis but not with that of the slip. Posterior fusion was used in 54, posterolateral in 30 and anterior fusion in three patients. There were no major complications but 16 had re-operations for non-union or root symptoms. At follow-up there were three non-unions. After operation, 19 patients had 10% or more progression of the slip, but 10 showed correction by more than 10% as a result of remodelling. The lumbosacral kyphosis had increased by more than 10 degrees in 45%. Postoperative progression of the slip and of lumbosacral kyphosis was significantly more if the posterior element had been removed. At follow-up 77 patients were subjectively improved, four were unchanged, and one was worse. These results did not correlate with either the degree of the slip, or the angle of lumbosacral kyphosis. Fusion in situ is safe and gives good long-term clinical results. Secondary changes are associated with increased lumbosacral kyphosis, so reduction of this should be considered in severe cases.

Development of the hip in diastrophic dysplasia.

We examined 50 patients with diastrophic dysplasia both clinically and radiologically. Two legally aborted fetuses were dissected. The mean age of the patients was 16.2 years (newborn to 38) and the mean follow-up was 11.4 years (3 months to 34 years). The fetal hips and MRI of newborn infants showed congruity and no significant joint deformity. Flexion contracture of the hip became evident later in 93% and was progressive. The radiological appearance of the proximal femoral ossific nuclei was delayed and in 17% of males and 28% of females the ossific nuclei had not appeared by the age of 12 years. Radiological measurements differed considerably from reference values and were related to the rapid and progressive restriction of rotational movement and the increase in flexion contracture. The typical findings were flattening and inferomedial bulking of the femoral head and a double-hump deformation. The changes in the hip led to secondary osteoarthritis before early middle age. We describe the clinical and radiological measurements which define the early degeneration of the joint.