Aims

The primary aim of this prospective, multicentre study is to describe the rates of returning to golf following hip, knee, ankle, and shoulder arthroplasty in an active golfing population. Secondary aims will include determining the timing of return to golf, changes in ability, handicap, and mobility, and assessing joint-specific and health-related outcomes following surgery.

The function of the shoulder joint has traditionally been evaluated based on range of motion (ROM) in predefined anatomical planes and also by using functional scores, which assessed shoulder function based on the ability to conduct certain activities of daily living (ADLs). However, measuring ROM only in terms of flexion-extension, abduction-adduction and internal-external rotation may under-account for the 3-dimensional mobility of the shoulder joint. Furthermore, functional scores, such as the Oxford shoulder score or American shoulder and elbow surgeons (ASES) score, are subjective measures and are not an accurate assessment of shoulder joint function. In this study, we proposed the use of the globe model of the shoulder joint which can be used to provide an objective measure of the global ROM and also function of the shoulder joint – termed the Global and Functional arc of motion (GAM and FAM).

Thirty-three young, healthy male patients (23.7 ± 1.5 years) were recruited and tasked to perform eight ADLs and a full humeral circumduction movement which represented their active global ROM. Reflective markers were placed in accordance to the International Society of Biomechanics (ISB) and optical-based motion capture cameras were used to track relative motion of the dominant humerus with respect to the thorax (i.e. thoracohumeral motion). The GAM and FAM were generated by plotting the thoracohumeral on a spherical coordinate system during global ROM and the eight ADLs respectively. Shoulder joint global ROM and function were quantified by calculating the area enclosed by the closed loop of GAM and FAM respectively.

The spherical coordinate system, or more commonly referred to as the globe model, describes thoracohumeral movement using plane of elevation (POE), angle of elevation (AOE) and rotation. In our model, POE and AOE represents longitude and latitude of the globe respectively, and rotation is depicted using a red-green-blue (RGB) colour scale. Overall, subject's GAM of the shoulder joint covered an area of 4.64 ± 0.48 units2 compared to only 1.12 ± 0.26 units2 for the FAM. Subjects only required 24.4 ± 5.7 % of their global shoulder ROM for basic daily functioning.

Studies that reduced shoulder joint movement into planar movements (i.e. sagittal, coronal and rotation) do not account for the 3-dimensional nature of the joint and doing so may overestimate the requirement of the shoulder joint for ADLs relative to its ROM in each plane. While others have attempted to use the globe model, such studies tend to reduce the globe into its descriptive angles (i.e. POE, AOE and rotation), reducing its intuitiveness. In contrast, by keeping an intact globe, the proposed globe model was more intuitive and yet capable of quantifying both shoulder joint global ROM and function. Doing so, we found that young healthy subjects only required approximately a quarter of their global ROM of the shoulder joint to complete the most common daily tasks, which was significantly less than what was previously reported.

Age-related fragility fractures are highly correlated with the loss of bone integrity and deteriorated morphology of the osteocytes. Previous studies have reported low-magnitude high-frequency vibration(LMHFV) promotes osteoporotic diaphyseal fracture healing to a greater extent than in age-matched normal fracture healing, yet how osteoporotic fractured bone responds to the mechanical signal has not been explored. As osteocytes are prominent for mechanosensing and initiating bone repair, we hypothesized that LMHFV could enhance fracture healing in ovariectomized metaphyseal fracture through morphological changes and mineralisation in the osteocyte Lacuno-canalicular Network(LCN). As most osteoporotic fractures occur primarily at the metaphysis, an osteoporotic metaphyseal fracture model was established.

A total of 72 six-month old female Sprague-Dawley rats (n=72) were obtained(animal ethical approval ref: 16–037-MIS). Half of the rats underwent bilateral ovariectomy(OVX) and kept for 3 months for osteoporosis induction. Metaphyseal fracture on left distal femur was created by osteotomy and fixed by a plate. Rats were then randomized to (1) OVX+LMHFV(20 mins/day and 5 days/week, 35Hz, 0.3g), (2) OVX control, (3) SHAM+LMHFV, (4) SHAM control. Assessments of morphological structural changes, functional markers of the LCN(Scanning Electron Microscopy, FITC-Imaris, immunohistochemistry), mineralization status(EDX, dynamic histomorphometry) and healing outcomes(X-ray, microCT, mechanical testing) were performed at week 1, 2 and 6 post-fracture. One‐way ANOVA with post-hoc test was performed. Statistical significance was set at p < 0.05.

Our results showed LMHFV could significantly enhance the morphology of the LCN. There was a 65.3% increase in dendritic branch points(p=0.03) and 93% increase in canalicular length(p=0.019) in the OVX-LMHFV group at week 2 post-fracture. Besides, a similar trend was also observed in the SHAM+LMHFV group, with a 43.4% increase in branch points and 53% increase in canaliculi length at week 2. A significant increase of E11 and DMP1 was observed in the LMHFV groups, indicating the reconstruction of the LCN. The decreasing sclerostin and increasing FGF23 at week 1 represented the active bone formation phase while the gradual increase at week 6 signified the remodelling phase. Furthermore, Ca/P ratio, mineral apposition rate and bone formation rate were all significantly enhanced in the OVX+LMHFV group. The overall bone mineral density in BV was significantly raised in the OVX+LMHFV group at week 2(p=0.043) and SHAM+LMHFV at week 6(p=0.04). Quantitative analysis of microCT showed BV/TV was significantly increased at week 2 in OVX+LMHFV group(p=0.008) and week 6(p=0.001) in both vibration groups. In addition, biomechanical testing revealed that the OVX+LMHFV group had a significantly higher ultimate load(p=0.03) and stiffness(p=0.02) at week 2.

To our best knowledge, this is the first report to illustrate LMHFV could enhance osteocytes' morphology, mineralisation status and healing outcome in a new osteoporotic metaphyseal fracture animal model. Our cumulative data supports that the mechanosensitivity of bone would not impair due to osteoporosis. The revitalized osteocyte LCN and upregulated osteocytic protein markers implied a better connectivity and transduction of signals between osteocytes, which may foster the osteoporotic fracture healing process through an enhanced mineralisation process. This could stimulate further mechanistic investigations with potential translation of LMHFV to our fragility fracture patients.

Mathematical modeling provides an efficient and easily reproducible method for the determination of joint forces under in vivo conditions. The need for these new modeling methodologies is needed in the lumbar spine, where an understanding of the loading environment is limited. Few studies using telemetry and pressure sensors have directly measured forces borne by the spine; however, only a very small number of subjects have been studied and experimental conditions were not ideal for giving total forces acting in the spine. As a result, alternative approaches for investigating the lumbar spine across different clinical pathologies are essential. Therefore, the objective of this study was to develop of an inverse dynamic mathematical model for theoretically deriving in-vivo contact forces as well as musculotendon forces in patients having healthy, symptomatic, pathological and post-operative conditions of the lumbar spine.

Fluoroscopy and 3D-to-2D image registration were used to obtain kinematic data for patients performing flexion-extension of the lumbar spine. This data served as input into the multi-body, mathematical model. Other inputs included patient-specific bone geometries, recreated from CT, and ground reaction forces. Vertebral bones were represented as rigid bodies, while massless frames symbolized the lower body, torso and abdominal wall (Figure 1). In addition, ligaments were selected and modeled as linear spring elements, along with relevant muscle groups. The muscles were divided into individual fascicles and solved for using a pseudo-inverse algorithm which enabled for decoupling of the derived resultant torques defining the desired kinetic trajectory for the muscles.

The largest average contact forces in the model for healthy, symptomatic, pathological, and post-operative lumbar spine conditions occurred at maximum flexion at L4L5 level and were predicted to be 2.47 BW, 2.33 BW, 3.08 BW, and 1.60 BW, respectively. The FE rotation associated with these theoretical force values was 43.0° in healthy, 40.5° in symptomatic, 44.4° in pathological, and 22.8° in post-operative patients. The smallest forces occurred as patients approached the upright, standing position, followed by slight increases in the contact force at full extension. The theoretically derived muscle forces exhibited similar contributory force profiles in the intact spine (healthy, symptomatic, and pathologic); however, surgically implanted spines experienced an increase in the contribution of the external oblique muscles accompanied with decreased slope gradients in the muscle force profiles (Figure 2).

These altered force patterns may be associated with the decrease in the predicted contact forces in post-operative patients. In addition, the decreased slope gradients in surgically implanted patients corresponds with the observed difficulty of performing the prescribed motion, possibly due to improper muscle firing, thereby leading to slower motion cycles and less ranges-of-motion. On the contrary, patients having an intact spine performed the activity at a faster speed and to greater ranges-of-motion, which corresponds with the higher contact forces derived in the model. In conclusion, this research study presented the development of a mathematical modeling approach utilizing patient-specific data to generate theoretical in-vivo joint forces. This may serve to help progress the understanding for the kinetic characteristics of the native and surgically implanted lumbar spine.

Introduction

Numerous studies have been conducted to investigate the kinematics of the lumbar spine, and while many have documented its intricacies, few have analyzed the complex coupled out-of-plane rotations inherent in the low back. Some studies have suggested a possible relationship between patients having low back pain (LBP) or degenerative conditions in the lumbar region and various degrees of restricted, excessive, or poorly-controlled lumbar motion. Conversely, others in the orthopedic community maintain there has been no distinct correlation found between spinal mobility and clinical symptoms. The objective of this study was to evaluate both the in-plane and coupled out-of-plane rotational magnitudes about all three motion axes in both symptomatic and asymptomatic patients.

Introduction

Different subclinical neurological dysfunction has been reported in adolescent idiopathic scoliosis (AIS), including poor postural control and asymmetric otolith vestibulo-ocular responses when compared with normal controls. The objective of this pilot study is to establish whether abnormal MRI morphoanatomical changes arise in the CNS (brain and vestibular system), among left-thoracic versus right-thoracic AIS when compared with normal adolescent controls, with use of advanced computerised statistical morphometry techniques.

Introduction

Genetic predisposition is a key causal factor in adolescent idiopathic scoliosis (AIS), which is the most common form of spinal deformity. However, common quantitative genetic effect estimates such as hereditability have not been fully evaluated and reported for this disorder. We aimed to determine the sibling recurrent risk and hereditability of AIS in first-degree relatives of 513 Chinese patients with this disorder.

Introduction

Despite extensive research, the cause of adolescent idiopathic scoliosis (AIS) is still largely unclear. Girls with AIS tend to be taller and leaner, and have a lower body-mass index (BMI) and lower bone mass, than do healthy girls. Recent MRI studies have shown the presence of relative anterior spinal overgrowth in girls with AIS. The lower bone mineral status and BMI could be related to dysfunctional central regulation pathway of growth, bodyweight, and bone metabolism. Following several interesting reports on the role of leptin in regulation of the above pathway in animals and human beings, our recent study has shown a low leptin concentration in girls with AIS girls compared with healthy adolescents. This finding leads to our new hypothesis that abnormal leptin bioavailability could be associated with the lower bodyweight, lower bone mineral density, and relatively disproportional endochondral skeletal growth in AIS. This study aimed to investigate the leptin bioavailability in girls with AIS.

Introduction

Adolescent idiopathic scoliosis (AIS) is associated with low bone mineral density, which could be related to its etiopathogenesis. Apart from bone density, bone micro-architectures are equally important for better understanding of disease initiation and progression in AIS. Quantitative assessment of bone quality is hampered by the invasive nature of investigations, until recently when the high-resolution pQCT (XtremeCT) became available for revolutionary in-vivo microimaging and derivation of bone micro-architectural parameters. Our objective was to use this powerful instrument to study bone qualities in AIS and compare findings with those from healthy controls.

Introduction

The main challenge in management of adolescent idiopathic scoliosis (AIS) is to predict which curve will progress so that appropriate treatment can be given. We previously reported that low bone mineral density (BMD) was one of the adverse prognostic factors for AIS. With advancement in imaging technology, quantitative ultrasound (QUS) becomes a useful method to assess bone density and bone quality. The objective of this study was to assess the role of QUS as a radiation-free method to predict curve progression in AIS.

The purpose of this study is to investigate the incidence of patients with isolated bundle ACL tear (either isolated posterolateral or anteromedial bundle) during arthroscopy, and its correlation with physical exam. The relevant surgical technique to reconstruct the ligament is discussed.

Between September 2006 and March 2009, patients with ACL injuries who received double- bundle ACL reconstruction were reviewed retrospectively. A specialist fellow performed a physical exam before and after anaesthesia. Intraop status of the ACL tear was assessed with correlation of the physical findings. Patients with isolated bundle tear would receive anatomical reconstruction of the torn bundle with preservation of the intact bundle.

Double-bundle hamstrings reconstruction would be performed to those with complete tear. Medical notes of 159 patients were reviewed. There were 118 patients (74%) with complete ACL tear, 36 (23%) with isolated AM tear, and 5 (3%) with PL tear.

For patients with complete ACL tear, 94% and 100% had positive Lachman, 50% and 87% had positive pivot shift, before and after anaesthesia. For patients with isolated AM tear, 100% had positive Lachman, 36% and 19% had positive pivot shift, before and after anaesthesia.

For patients with isolated PL tear, 100% had positive Lachman, 20% and 80% had positive pivot shift, before and after anaesthesia.

With better understanding of ACL, patients with isolated-bundle tear can preserve their intact bundle during reconstruction. However, in this study we find that physical exam correlates poorly with the arthroscopic findings.

Further imaging (e.g. MRI) may be helpful to differentiate patients from isolated- bundle tear to complete tear.

Low back pain (LBP) in the region of the lumbar spine is a significant problem among individuals, and efforts focused on treating both the symptoms and causes of LBP have proven to be difficult. Aside from conservative treatments, the predominant surgical approach for treating degenerative spine conditions has been to fuse the vertebral bodies at the symptomatic level. Even today, surgical fusion and its effect on adjacent levels are still not fully understood. Therefore, the objective of this study was to use fluoroscopy and mathematical modeling techniques to identify the in vivo kinematics and kinetics in subjects having either a normal, degenerative or fused condition of the lumbar spine.

Twenty-five subjects (ten normal, ten degenerative, and five fusion) were evaluated under fluoroscopic surveillance while performing flexion/extension of the lumbar spine. Subjects within the normal and degenerative groups were analyzed only once, while subjects from the fusion group were analyzed both pre-operatively and at a minimum of six months post-operative. The fusion group consisted of three subjects symptomatic at L4/L5, with the remaining two subjects symptomatic at L5/S1. In vivo kinematics data were derived using a 3D-to-2D model fitting algorithm and served as input into a 3D mathematical model of the lumbar spine. The parametric, inverse dynamics mathematical model was created to allow for the determination of the bearing surface contact and muscle forces at each level of the lumbar spine.

Three-dimensional kinematics analyses revealed that subjects classified as having a normal lumbar spine experienced a more uniform motion pattern compared to those observed in the degenerative and fusion groups. Alternatively, the degenerative and fusion subjects demonstrated a more coupled motion pattern in order to perform in plane flexion/extension. Compared to the normal group, rotations in the sagital plane decreased by an average of 28% at the pathological level in the degenerative group, while in the fusion group segmental motions slightly increased at the adjacent levels. Results from the mathematical model also revealed higher out-of-plane forces and increased loading at symptomatic and adjacent levels in both the degenerative and fused groups compared to forces observed in the normal spine.

The abnormal motion patterns, which result from decreased or loss of motion at pathological levels in the degenerative and fusion groups, are believed to result in higher resultant forces in the spine. This may be subjecting the intervertebral discs to increased stresses, and as a consequence may be linked to more rapid degeneration at levels where the abnormal kinematics are occurring.

Observation of sub-clinical neurological abnormalities has led to the proposal of a neuro-developmental etiologic model for AIS. Our research group have demonstrated longer latency in somatosensory–evoked potential (SSEP) and impaired balance control in AIS subjects. A previous pilot study compared the regional brain volume between right thoracic AIS subjects and normal controls. Significant regional brain differences were found relating to corpus callosum, premotor cortex, proprioceptive and visual centers. Most of these regions involved the brain unilaterally, indicating there might be abnormal asymmetrical development in the brain in right thoracic AIS. In this pilot study, we investigated whether similar changes are present in left thoracic AIS patients who differ from matched control subjects. Nine AIS female patients with atypical left thoracic AIS (mean age 14.8, mean Cobb angle 19°) and 11 matched controls as well as 20 right thoracic AIS (mean Cobb angle 33.8°) and 17 matched controls, underwent three-dimensional isotropic magnetization prepared rapid acquisition gradient echo (3D_MPRAGE) magnetic resonance (MR) imaging of the brain. Fully automatic morphometric analysis was used to analyse the MR images; it included brain-tissue classification into grey matter (GM), white matter (WM) and cerebrospinal fluid (CSF). and non-linear registration to a template brain. Tissue densities were compared between AIS subjects and controls. There was no significant difference between AIS subjects and normal controls when comparing absolute and relative (i.e. brain-size adjusted) volumes of grey and white matter. Using voxel-based morphometry, significant group differences (controls > left AIS) were found in the density of WM in the genu of the corpus callosum, the left internal capsule (anterior arm) and WM underlying the orbitofrontal cortex of the left hemisphere. The above differences were not observed in the right AIS group. This first controlled study of regional tissue density showed that corpus callosum, which is the major commissural fiber tract, was different in the atypical left thoracic scoliosis while significant regional brain changes have not yet been found in those with typical right thoracic scoliosis. Further investigation is warranted to see whether the above discrepancy is related to laterality of the scoliotic curves and infratentorial neuroanatomical abnormalities. A larger sample and a longitudinal study is required to establish whether the brain abnormalities are predictive of curve progression.

Introduction: Observation of sub-clinical neurological abnormalities has led to the proposal of a neuro-developmental etiologic model for adolescent idiopathic scoliosis (AIS). We have previously demonstrated prolonged latency in somatosensory evoked potentials (SSEP) and impaired balance control in subjects with AIS. Furthermore we have compared regional brain volumes in right thoracic AIS subjects and normal controls. Significant neuro-anatomic regional differences were observed in the corpus callosum, premotor cortex, proprioceptive and visual centers of the AIS subjects compared to control subjects. Most of these regional differences involved the brain unilaterally, indicating there may be abnormal asymmetrical development in the brain of subjects with right thoracic AIS.

Methods: Following ethical committee approval a total of 29 subjects with AIS were recruited. Patients with congenital, neuromuscular or syndromic scoliosis were excluded from the study. Twenty-eight age- and sex-matched controls were recruited from local schools. All recruits underwent three-dimensional isotropic magnetization prepared rapid acquisition gradient echo (3D_MPRAGE) magnetic resonance (MR) imaging of the brain. Modern morphometric analyses of the MR images were carried out including classification of tissue into grey matter (GM), white matter (WM) and cerebrospinal fluid (CSF). Tissue densities were compared between AIS subjects and controls. Comparisons were made between those subjects with left thoracic AIS (n=9) and age and sex-matched controls (n=11) and those subjects with right thoracic AIS (n=20) and age and sex-matched controls (n=17).

Results: For subjects with left thoracic curves the mean Cobb angle was 19 degrees. For subjects with right thoracic curves the mean Cobb angle was 33.8 degrees There was no significant differences observed between AIS subjects and normal controls when comparing both absolute and relative (i.e. adjusted for brain size) volumes of GM and WM. However voxel-based morphometric analysis identified significant differences in the density of WM in the genu of the corpus callosum, the left internal capsule and WM underlying the left orbitofrontal cortex when comparing those subjects with left thoracic scoliosis to controls. The above differences were not not observed when those subjects with right thoracic scoliosis were compared to controls..

Discussion: This controlled study of regional brain tissue density has demonstrated important differences in the corpus callosum, the left internal capsule and the left orbitofrontal cortex when the brain of those subjects with left thoracic scoliosis is compared to age and sex matched controls. In this study significant regional brain differences have not been identified in those subjects with right thoracic scoliosis. Further studies are warranted to ascertain whether these morphologial differences in the brain are linked with the etiopathogenisis of left sided thoracic scoliosis. A larger sample and a longitudinal study are required to establish whether brain abnormalities are predictive of curve progression.

Background: Adolescent Idiopathic Scoliosis is a 3-dimensional deformity of the spine affecting peri-pubertal adolescents (10-17-y) mostly. Although generalised osteopenia is well documented in AIS, the patho-physiology of AIS related osteopenia is uncertain.

Aim: We studied the association between pubertal-growth, BMD, bone-turnover, calcium intake (CA) and physical-activity (PA) in AIS and compared to those of healthy girls.

Methods: 894 girls (594 AIS & 300 healthy controls) aged 11–16-y entered the study. Anthropometric parameters, areal-BMD of the proximal-femur and volumetric-BMD of the distal-tibia were determined by Dual-x-ray-Absorptiometry and peripheral QCT respectively. Bone-turnover-markers: bone-alkaline-phosphatase (bALP) and deoxypyridonine (Dpd) were assayed. CA and weight-bearing PA were assessed by FFQ method.

Results: Weight of AIS at < 12-y and 13-y was significantly lower than controls (P< 0.05). From 13-y, corrected right and arm-span of AIS were significantly longer than the controls (P< 0.02). aBMD and vBMD were 6.7% and 8.4% respectively lower than the controls across the ages (P< 0.05). The disparity in BMD compared with controls increased with age. CA was not different between the AIS and controls (361 mg/d, IQR:230–532mg/d vs. 319 mg/d, IQR:220–494mg/d; P=0.063). Weight-bearing PA of AIS was significantly lower than those of controls (P< 0.02).

CA of AIS and controls reached < 40% of the Chinese calcium DRI (1000 mg/d). Both CA and weight-bearing PA were correlated with BMD in AIS (P< 0.04 & P=0.002 respectively). Both CA and PA were independent predictors on the variations of aBMDs (P< 0.03) and vBMDs (P< 0.04) in AIS after controlling for confounders in multivariate analysis. Regarding bone turn-over rate, bALP in AIS was 38.6% higher than the controls from 13-y onwards (P< 0.005) while Dpd of AIS was 30.4% lower than controls at age 15-y (P=0.003). Furthermore, bALP in AIS was negatively correlated with age-adjusted BMD (r=−0.34, P< 0.001) while the correlation was weaker in the controls (P=0.14, P< 0.002).

Conclusion: The correlation of calcium intake and physical activity with BMD occurred predominantly in AIS only and that these two factors were also independent determinants on BMD of AIS implying that calcium intake and physical activity were significant modulators on BMD in AIS. Significantly faster physical-growth, higher bone formation rate were associated with lower BMD. Osteopenia in AIS could be interplayed by abnormally faster pubertal-growth and bone-turnover. In fact, Calcium intake of AIS was too low to meet the calcium demand for bone-mineralization. A controlled calcium supplementation and programmed physical activity intervention trial is merited to confirm the effect of Calcium intake and physical activity on bone acquisition in AIS at peripubertal period.

Background: Low bone mass in patients with adolescent idiopathic-scoliosis has been well reported in cross-sectional studies. No large-scale longitudinal-study has been conducted to track bone-mineral-density (BMD) trajectory in peripubertal AIS with varying scoliosis-severity.

Aim: We evaluated the BMD trajectory and factors determining BMD accretion in AIS during peripubertal period.

Method: One hundred and ninety-six newly diagnosed AIS girls with Cobb-angle > 100 and 122 healthy girls, aged 12–15 years were followed-up for two years. Weight, height, leg length, menarche and Cobb-angle were determined. Areal lumbar-spinal BMD (LSBMD) and femoral-neck BMD (FNBMD), and volumetric distal-tibial BMD (TiBMD) were evaluated by dual-energy-x-ray-absorptiometry and peripheral QCT respectively. BMD growth-models were fitted by multilevel modelling (mixed longitudinal design).

Results: At baseline, 93% participants were pre-menarchial or within three years of menarche. Average Cobb-angles at baseline and subsequent follow-ups were 260, 230 and 260 respectively. TiBMD of AIS (moderate- and severe-severity) was significantly lower than the controls from 13–16 years (ANOVA, P< 0.05). Posthoc-test showed that TiBMD of severe-AIS was lower than moderate-AIS at 15–16 years (P< 0.05). LSBMD accrual was significantly lower among AIS (moderate- and severe-severity) than the controls from age 13–17 years (ANOVA, P< 0.05). FNBMD of AIS (moderate- and severe-severity) was lower than the controls at 15 years (ANOVA, P< 0.05). BMD trajectories of individuals differed inter-personally and intra-personally over time and that BMD growth followed a curvilinear pattern. The rates of BMD accretion reduced with retarded growth across peripubertal-period. Weight and height were significant time-varying predictors on BMD growth. BMD of AIS was persistently lower than the healthy girls throughout the study (P< 0.05).

Conclusions: This large-scale longitudinal study in AIS girls with moderate to severe-curve-severity showed for the first time that both the volumetric and areal BMD were persistently lower when compared to the age-matched healthy girls throughout 12–17 years. AIS with more severe curve-severity were found to have much lower BMD throughout the peripubertal period. Promotion of a higher bone-mass is important for AIS to modify scoliosis-progression and to achieve peak bone mass in order to reduce the risk of osteoporosis later in life.

We performed 52 total hip replacements in 52 patients using a cementless acetabular component combined with a circumferential osteotomy of the medial acetabular wall for the late sequelae of childhood septic arthritis of the hip. The mean age of the patients at operation was 44.5 years (22 to 66) and the mean follow-up was 7.8 years (5 to 11.8). The mean improvement in the Harris Hip Score was 29.6 points (19 to 51) at final follow-up. The mean cover of the acetabular component was 98.5% (87.8% to 100%). The medial acetabular wall was preserved with a mean thickness of 8.3 mm (1.7 to 17.4) and the mean length of abductor lever arm increased from 43.4 mm (19.1 to 62) to 54.2 mm (36.5 to 68.6). One acetabular component was revised for loosening and osteolysis 4.5 years postoperatively, and one had radiolucent lines in all acetabular zones at final review. Kaplan-Meier survival was 94.2% (95% confidence interval 85.8% to 100%) at 7.3 years, with revision or radiological loosening as an end-point when two hips were at risk.

A cementless acetabular component combined with circumferential medial acetabular wall osteotomy provides favourable results for acetabular reconstruction in patients who present with late sequelae of childhood septic hip arthritis.

Out of a total of 112 children with displaced forearm shaft fracture treated with Percutaneous Kirschner (K) wire fixation in the past 9 years, 84 cases with fracture of both the radius and ulna were reviewed. 64 (76%) had fixation of both the radius and ulna, 10 (12%) the radius only and the other 10 (12%) the ulna only. In 60 (71%) patients were successful with one stage close reduction and pinning, while in the remaining 24 (29%) a semi- open reduction through a small incision was required. The K-wire was inserted through the radial styloid or the Lister tubercle for the radius, and through the tip of the olecranon for the ulna. All the patients reviewed were found to have good functional results with no non-union, deep infection or premature physeal closure at a mean follow-up of 48 months. Initial pre-operative shortening or translation of the fracture were associated with significantly higher chance of open reduction. We concluded that percutaneous K-wiring for forearm diaphyseal fracture in children is a convenient, effective and safe operation, with minimal complications.

“Subacute Synovities of the Hip”, which runs a more fluctuant clinical progress and slower response to treatment than those of acute transient synovitis, is always posing diagnostic and management challenge in children presented with acute hip pain. This study aims to identify the special features of this distinct entity, and the important diagnostic parameters in differentiation of acute transient synovitis, subacute arthritis and also septic arthritis in children presented with acute painful pain. From 1985–1999, 427 children have been admitted into our centre with subsequent diagnosis of acute transient synovitis, subacute synovitis & septic arthritis. 320 cases with full records are available for review, with 270 cases 85%) having acute transient synovitis, 35 cases (10%) of subacute arthritis and 15 cases (5%) of septic arthritis. Statistical results showed that patient having subacute arthritis different significantly from those with acute transient synovitis in terms of age of presentation & duration of symptoms before hospitalization. Moreover, patient having transient synovitis significantly different from those with septic arthritis in terms of temperature on admission, ESR and White Cell Count.

In Northern China, Ca intake and serum vitamin-D level of adolescents are low due to non-dairy-based diets and insufficient sunshine exposure. Maximisation of bone mineral accretion in childhood and adolescence requires adequate dietary calcium (Ca) intake and body vitamin-D status. This study focused on nutritional adaptation in Chinese adolescents under these adversed conditions by determining Ca absorption (CaAbn) and urinary calcium excretion (CaEx).

16 healthy individuals (12 girls, 4 boys) aged 9–17-y were recruited from Beijing during December. CaAbn was determined by a dual stable-isotope technique (44Ca and 42Ca) coupled with a Thermal-Ionization -Mass-Spectrometer.

Mean ± sd Ca intake, 24-h CaEx, and serum 25-(OH) vitamin D3 were 603 ±158 mg/d, 87.5 ± 59.2 mg/24-h and 13.7 ± 4.8 ng/mL respectively. Mean serum 25-(OH) vitamin D3 reached the lower normal-limit of 11 ng/mL. 24-h-CaEx (< 100 mg/d) reflected a higher efficiency of Ca retention. CaAbn was found 57.4 ± 15.4% which was significantly higher than the U.S. counterparts (25–34%; Ca intake: 925 mg/d), P< 0.05. However, CaAbn in the current study was comparable to a group of healthy Hong Kong children aged 7-y (CaAbn: 54.8%, Ca intake: 862 mg/d, serum 25-(OH) vitamin D3:33.3 ng/mL).

The study showed that growing individuals with suboptimal vitamin D status are still capable of enhancing calcium absorption and reducing urinary calcium excretion to allow adequate bone Ca accretion.