T. P. Lam

Closed reduction and percutaneous pinning for type III displaced supracondylar fractures of the humerus in children.

Summary: From 1985 to 1991, 623 cases of supracondylar fracture of the humerus in children were admitted to one center, of which 403 were analyzed in detail. Of these, 180 cases were classified as Gartland type III extension fractures, and 111 were treated via primary closed reduction and percutaneous smooth Kirschner wire pinning, of which 82 were followed up for an average of 3.5 years and were studied in detail clinically and radiologically. There were two cases of superficial pin tract infection and one of ulnar nerve palsy associated with the pinning. Nineteen fractures (10.5%) had an initial nerve palsy related to the injury. All recovered completely from 4 weeks to 40 weeks postinjury. Only one of nine cases (5%) with absent radial pulse required exploration. Eighty percent of all cases had excellent or good function according to the Flynn criteria of elbow assessment. The most important factor correlating with the final varus deformity was found to be the difference in Baumanns angle between the injured and the normal side after closed reduction and pin fixation. The results of cross pinning in eight cases were not found to be different from those of the lateral pinning group (74 cases). Ipsilateral fracture of the same limb occurred in 4.4% of the cases, the majority being a fracture of the distal radius. The average anesthetic time for the procedure was 54 min, and the average hospital stay was 2.9 days. Our study shows that cross or lateral percutaneous pinning was found to be effective in the treatment of Gartland type III extension fractures with a high success rate and minimal complications

Osteopenia: A New Prognostic Factor of Curve Progression in Adolescent Idiopathic Scoliosis

BACKGROUND Studies have shown that 27% to 38% of girls with adolescent idiopathic scoliosis have systemic osteopenia. The aim of this study was to investigate whether osteopenia could serve as one of the important prognostic factors in predicting curve progression. METHODS A prospective study was performed in 324 adolescent girls with adolescent idiopathic scoliosis who had a mean age of thirteen and a half years. Bone mineral density of the spine and both hips was measured at the time of the clinical diagnosis of scoliosis. All patients were followed longitudinally until skeletal maturity or until the curve had progressed > or =6 degrees . The univariate chi-square test and stepwise logistic regression were used to predict the prevalence of curve progression, and a receiver operating characteristic curve was plotted. RESULTS The overall prevalence of curve progression was 50%. The prevalence of osteopenia at the spine and hips was 27.5% and 23.1%, respectively. A larger initial Cobb angle (odds ratio = 4.6), a lower Risser grade (odds ratio = 4.7), premenarchal status (odds ratio = 2.5), osteopenia in the femoral neck of the hip on the side of the concavity (odds ratio = 2.3), and a younger age at the time of diagnosis (odds ratio = 2.1) were identified as risk factors in predicting curve progression. A predictive model was established, and the area under the receiver operating characteristic curve of the model was 0.80 (p < 0.01). CONCLUSION Osteopenia may be an important risk factor in curve progression. The measurement of bone mineral density at the time of diagnosis may serve as an additional objective measurement in predicting curve progression in adolescent idiopathic scoliosis. The bone mineral density-inclusive predictive model may be used in treatment planning for patients with adolescent idiopathic scoliosis who are at high risk of curve progression.

A study of bone marrow and subcutaneous fatty acid composition in subjects of varying bone mineral density

Osteoporosis is associated with an increase in marrow fat. Fats, particularly polyunsaturated fats, either in co-cultures or diet, have been shown to significantly influence bone remodeling. Whether the increase in marrow fat seen in osteoporosis is also associated with a change in fatty acid composition is not known. This study was undertaken to investigate the fatty acid composition in subjects of varying bone mineral density (BMD). Samples of marrow fat and subcutaneous fat from 126 subjects (98 females, 34 males, mean age 69.7+/-10.5 years) undergoing orthopedic surgery were analyzed for fatty acid composition by gas chromatography. These results were correlated with BMD assessed by DXA. A total of 22 fatty acids were identified in marrow and subcutaneous fat. Significant differences in fatty acid composition existed between marrow and subcutaneous fat as well as between marrow fat samples obtained from the proximal femur and proximal tibia. Other than cis-7-hexadecenoic acid [C16:1 (n=9)] and docosanoic acid [C22:0], no difference in marrow fatty acid composition was evident between subject groups of varying BMD (normal, low bone mass, and osteoporosis). In conclusion, there exists a wide range of individual fatty acids in marrow fat. Marrow fatty acid composition differs from that of subcutaneous fat and varies between predominantly erythropoetic and fatty marrow sites. Other than cis-7-hexadecenoic acid [C16:1 (n=9)] and docosanoic acid [C22:0], no difference in marrow fatty acid composition was evident between subjects of varying BMD.

The conservative management of acute pyogenic iliopsoas abscess in children

We describe three cases of acute pyogenic abscess of the iliopsoas in children treated conservatively. Two patients had image-guided aspiration and one was managed with antibiotics alone. All made a complete recovery. Acute pyogenic abscess of the iliopsoas in children can be treated effectively and safely with intravenous antibiotics and image-guided aspiration of the abscess.

Genome-wide association study identifies new susceptibility loci for adolescent idiopathic scoliosis in Chinese girls

Adolescent idiopathic scoliosis (AIS) is a structural deformity of the spine affecting millions of children. As a complex disease, the genetic aetiology of AIS remains obscure. Here we report the results of a four-stage genome-wide association study (GWAS) conducted in a sample of 4,317 AIS patients and 6,016 controls. Overall, we identify three new susceptibility loci at 1p36.32 near AJAP1 (rs241215, Pcombined=2.95 × 10−9), 2q36.1 between PAX3 and EPHA4 (rs13398147, Pcombined=7.59 × 10−13) and 18q21.33 near BCL-2 (rs4940576, Pcombined=2.22 × 10−12). In addition, we refine a previously reported region associated with AIS at 10q24.32 (rs678741, Pcombined=9.68 × 10−37), which suggests LBX1AS1, encoding an antisense transcript of LBX1, might be a functional variant of AIS. This is the first GWAS investigating genetic variants associated with AIS in Chinese population, and the findings provide new insight into the multiple aetiological mechanisms of AIS.

Femoral lengthening after type IVB septic arthritis of the hip in children.

Septic arthritis of the hip in the newborn baby can result in severe long-term sequelae in the form of dislocation of the hip, loss of movement, and growth disturbance with leg-length discrepancy. For more severe discrepancies often with concomitant hip dislocation, no good solutions are readily available. This series comprised four patients with Chois type IVB septic hip sequelae. They all had associated multiple-joint sepsis and resultant major leg-length discrepancies ranging from 6.9 to 14 cm. All underwent distraction lengthening with simultaneous correction of angulation and other deformities of the femur, three with the Ilizarov and one with the Orthofix system. The age at operation ranged from 9 to 13 years, with an average follow-up of 3 years. The overall lengthening achieved ranged from 4.5, 6.8, 12, to 13 cm, with the lengthening index from 24 to 51 days/cm. All hips remained stable, and the loss of range of hip and knee motion was not significant. Other complications included one deep pin-tract infection and one fracture of the callus.

[Closed reduction and percutaneous pinning for acute type III extension- Supracondylar fracture of distal humerus in children.].

SummaryGoal of SurgeryClosed reduction of acute type III (according to Gartland) supracondylar extension fractures of the distal humerus and unicondylar pin fixation.IndicationsType III and unstable type II supracondylar fractures.ContraindicationsSwelling of the elbow.Compartment syndrome.Preoperative Work UpRadiographs of both elbows in the anterior-posterior and lateral projections.Positioning and AnaesthesiaSupine with arm on arm board.General anaesthesia.Surgical TechniqueClosed reduction through manipulation under fluoroscopic control. Fixation with 2 Kirschner wires introduced percutaneously through the lateral condyle. Long arm cast for 4 to 5 weeks.Postoperative ManagementRadiographs on the first postoperative day, 1 week later and at time of cast and pin removal 4 to 5 weeks postoperatively. At that time active mobilisation of the elbow is started.Follow-up for 1 to 2 years is recommended.Possible ComplicationsDamage of ossific nucleus of physis.Damage to neurovascular structures.Wire migration.Pin tract infection.ResultsOut of 82 children (mean age 6.5 years) 73 had a follow-up of more than 6 months. 80.8% had good or excellent results. 15.1% had a decrease of the carrying angle of more than 10° (4.1% more than 20°). There were 2 pin tract infections and 1 iatrogenic transient ulnar palsy.

Geschlossene Reposition und perkutane Drahtfixation kindlicher suprakondylärer Extensionsfrakturen vom Typ III

SummaryGoal of SurgeryClosed reduction of acute type III (according to Gartland) supracondylar extension fractures of the distal humerus and unicondylar pin fixation.IndicationsType III and unstable type II supracondylar fractures.ContraindicationsSwelling of the elbow.Compartment syndrome.Preoperative Work UpRadiographs of both elbows in the anterior-posterior and lateral projections.Positioning and AnaesthesiaSupine with arm on arm board.General anaesthesia.Surgical TechniqueClosed reduction through manipulation under fluoroscopic control. Fixation with 2 Kirschner wires introduced percutaneously through the lateral condyle. Long arm cast for 4 to 5 weeks.Postoperative ManagementRadiographs on the first postoperative day, 1 week later and at time of cast and pin removal 4 to 5 weeks postoperatively. At that time active mobilisation of the elbow is started.Follow-up for 1 to 2 years is recommended.Possible ComplicationsDamage of ossific nucleus of physis.Damage to neurovascular structures.Wire migration.Pin tract infection.ResultsOut of 82 children (mean age 6.5 years) 73 had a follow-up of more than 6 months. 80.8% had good or excellent results. 15.1% had a decrease of the carrying angle of more than 10° (4.1% more than 20°). There were 2 pin tract infections and 1 iatrogenic transient ulnar palsy.

Bone Metabolism in AIS

Adolescent idiopathic scoliosis (AIS) occurs in children during their pubertal growth spurt. Rapid skeletal growth and abnormal anthropometric parameters are associated with the development and progression of scoliotic curves, with the curves stabilized when skeletal maturity is reached. Systemic osteopenia affecting multiple skeletal sites, defined as bone mineral density (BMD) of Z-score ≤ −1 with reference to the age and ethnic-matched population, was found by dual-energy X-ray absorptiometry (DXA) in over 30% of the AIS patients. The osteopenia could persist into adulthood, thus predisposing the AIS patients to osteoporosis and other related complications in later life. Osteopenia in AIS was shown to be an important prognostic factor for curve progression. Recent studies with advanced high-resolution peripheral quantitative computed tomography (HR-pQCT) revealed significant alterations in systemic bone geometry, micro-architecture, volumetric BMD, and mechanical bone strength (finite element analysis) in addition to osteopenia in AIS. Serological and cellular functional studies supported the presence of abnormal bone formation and resorption that might have contributed to the abnormal bone qualities and bone strength which could be linked to the etiopathogenesis of AIS. Physical activities, calcium and vitamin D intake, and genetics are important factors affecting bone mass in AIS. Recent RCT studies on whole-body vibration therapy and supplement therapy with calcium and vitamin D have shown to improve low bone mass in AIS significantly. A better understanding on the possible association between bone qualities and curve progression will shed light on future development of novel prognostic biomarkers and therapeutic strategies in AIS.

Altered White Matter Microstructure in the Corpus Callosum and Its Cerebral Interhemispheric Tracts in Adolescent Idiopathic Scoliosis: Diffusion Tensor Imaging Analysis

BACKGROUND AND PURPOSE: Neural system was one of the important contributors to the etiopathogenesis of adolescent idiopathic scoliosis; additionally, the morphology of corpus callosum interconnecting both hemispheres of the brain was found to be altered morphologically. Our aim was to evaluate and compare the microstructural changes of the corpus callosum and its interhemispheric white matter fiber tracts interconnecting both cerebral hemispheres in patients with adolescent idiopathic scoliosis and matched controls using diffusion tensor imaging. MATERIALS AND METHODS: Brain DTI was performed in 69 patients with adolescent idiopathic scoliosis (female, right thoracic/thoracolumbar curve) and 40 age-matched controls without adolescent idiopathic scoliosis (female). 2D and 3D segmentation of the corpus callosum were performed using a region-growing method, and the corpus callosum was further divided into 6 regions, including the rostrum, genu, anterior and posterior midbodies, isthmus, and splenium. The laterality index was calculated to quantify the asymmetry of the corpus callosum. Interhemispheric fiber tractography were performed using the Brodmann atlas. RESULTS: 2D ROI analysis revealed reduced fractional anisotropy in the genu and splenium (P = .075 and P = .024, respectively). Consistently reduced fractional anisotropy on the left sides of the genu and splenium was also found in 3D ROI analysis (P = .03 and P = .012, respectively). The laterality index analysis revealed a pseudo-right lateralization of the corpus callosum in adolescent idiopathic scoliosis. Interhemispheric fibers via the splenium interconnecting Brodmann 3, 1, and 2; Brodmann 17; and Brodmann 18 (corresponding to the primary somatosensory cortex and primary and secondary visual cortices) were also found to have reduced fractional anisotropy (P ≤ .05). CONCLUSIONS: Reduced fractional anisotropy was found in the genu and splenium of the corpus callosum and corresponding interhemispheric fiber tracts interconnecting the somatosensory and visual cortices via the splenium. Our results are suggestive of altered white matter microstructure within the brain of those with adolescent idiopathic scoliosis, which could be related to abnormal brain maturation during adolescence in adolescent idiopathic scoliosis and could possibly explain the previously documented somatosensory function impairment and visuo-oculomotor dysfunction in this condition.