Distal Radius Physeal Bar and Ulnar Overgrowth: Indications for Treatment.

BACKGROUND: Distal radius physeal bar with associated growth arrest can occur because of fractures, ischemia, infection, radiation, tumor, blood dyscrasias, and repetitive stress injuries. The age of the patient as well as the size, shape, and location of the bony bridge determines the deformity and associated pathology that will develop. METHODS: A search of the English literature was performed using PubMed and multiple search terms to identify manuscripts dealing with the evaluation and treatment of distal radius physeal bars and ulnar overgrowth. Single case reports and level V studies were excluded. RESULTS: Manuscripts evaluating distal radial physeal bars and their management were identified. A growth discrepancy between the radius and ulna can lead to distal radioulnar joint instability, ulnar impaction, and degenerative changes in the carpus and triangular fibrocartilage complex. Advanced imaging aids in the evaluation and mapping of a physeal bar. Treatment options for distal radius physeal bars include observation, bar resection±interposition, epiphysiodeses of the ulna±completion epiphysiodesis of the radius, ulnar shortening osteotomy±diagnostic arthroscopy to manage associated triangular fibrocartilage complex pathology, radius osteotomy, and distraction osteogenesis. CONCLUSIONS: Decision-making when presented with a distal radius physeal bar is multifactorial and should incorporate the age and remaining growth potential of the patient, the size and location of the bar, and patient and family expectations.

Does the Use of Sanders Staging and Distal Radius and Ulna Classification Avoid Mismatches in Growth Assessment with Risser Staging Alone?

BACKGROUND: Although Risser stages are visible on the same radiograph of the spine, Risser staging is criticized for its insensitivity in estimating the remaining growth potential and its weak correlation with curve progression in patients with adolescent idiopathic scoliosis. Risser staging is frequently accompanied by other skeletal maturity indices to increase its precision for assessing pubertal growth. However, it remains unknown whether there is any discrepancy between various maturity parameters and the extent of this discrepancy when these indices are used concurrently to assess pubertal growth landmarks, which are important for the timing of brace initiation and weaning. QUESTIONS/PURPOSES: (1) What is the chronologic order of skeletal maturity grades based on the growth rate and curve progression rate in patients with adolescent idiopathic scoliosis? (2) What are the discrepancies among the grades of each maturity index for indicating the peak growth and start of the growth plateau, and how do these indices correspond to each other? (3) What is the effectiveness of Risser staging, Sanders staging, and the distal radius and ulna classification in assessing peak growth and the beginning of the growth plateau? METHODS: Between 2014 and 2017, a total of 13,536 patients diagnosed with adolescent idiopathic scoliosis were treated at our tertiary clinic. Of those, 3864 patients with a radiograph of the left hand and wrist and a posteroanterior radiograph of the spine at the same visits including initial presentation were considered potentially eligible for this study. Minimum follow-up was defined as 6 months from the first visit, and the follow-up duration was defined as 2 years since initial consultation. In all, 48% (1867 of 3864) of patients were eligible, of which 26% (485 of 1867) were excluded because they were prescribed bracing at the first consultation. These patients visited the subsequent clinics wearing the brace, which might have affected body height measurement. Six percent (117 of 1867) of eligible patients were also excluded as their major coronal Cobb angle reached the surgical threshold of 50° and had undergone surgery before skeletal maturity. Another 21% (387 of 1867) of patients were lost before minimum follow-up or had incomplete data, leaving 47% (878) for analysis. These 878 patients with 1139 skeletal maturity assessments were studied; 74% (648 of 878) were girls. Standing body height was measured in a standardized manner by a wall-mounted stadiometer. Several surgeons measured curve magnitude as per routine clinical consultation, skeletal maturity was measured according to the distal radius and ulna classification, and two raters measured Risser and Sanders stages. Reliability tests were performed with satisfaction. Data were collected for the included patients at multiple points when skeletal maturity was assessed, and only up to when brace wear started for those who eventually had bracing. The growth rate and curve progression rate were calculated by the change of body height and major coronal Cobb angle over the number of months elapsed between the initial visit and next follow-up. At each skeletal maturity grading, we examined the growth rate (in centimeters per month) and curve progression rate (in degrees per month) since the skeletal maturity assessment, as well as the mean age at which this maturity grading occurred. Each patient was then individually assessed for whether he or she was experiencing peak growth and the beginning of growth plateau at each timepoint by comparing the calculated growth rate with the previously defined peak growth rate of ≥ 0.7 cm per month and the beginning of growth plateau rate of ≤ 0.15 cm per month in this adolescent idiopathic scoliosis population. Among the timepoints at which the peak growth and the beginning of growth plateau occurred, the median maturity grade of each maturity index was identified as the benchmark grade for comparison between indices. We used the McNemar test to investigate whether pubertal growth landmarks were identified by specific maturity grades concurrently. We assessed the effectiveness of these skeletal maturity indices by the difference in proportions (%) between two benchmark grades in indicating peak growth and the growth plateau. RESULTS: For girls, the chronological order of maturity grades that indicated peak growth was the radius grade, ulna grade, Sanders stage, and Risser stage. Curve progression peaked between the age of 11.6 and 12.1 years at a similar timing by all maturity indices for girls but was inconsistent for boys. For both sexes, radius (R) grade 6, ulna (U) grade 5, Sanders stage (SS) 3, and Risser stage 0+ were the median grades for peak growth, whereas Risser stage 4, R8/9, U7/8, and SS6/7 indicated the beginning of the growth plateau. The largest discrepancy between maturity indices was represented by Risser stage 0+, which corresponded to six grades of the Sanders staging system (SS2 to SS7) and to R6 in only 41% (62 of 152) of girls in the whole cohort. Despite Risser stage 0+ corresponding to the wide range of Sanders and distal radius and ulna grades, none of the R6, U5, SS3, and Risser stage 0+ was found more effective than another grade in indicating the peak growth in girls. R6 most effectively indicated the peak growth in boys, and Risser stage 0+ was the least effective. For the beginning of the growth plateau in girls, SS6/7 was the most effective indicator, followed by U7/8. Risser stage 4 was the least effective because it indicated 29% (95% CI 21% to 36%; p < 0.001) fewer patients who reached the beginning of the growth plateau than did those with R8/9. Risser stage 4 also indicated 36% (95% CI 28% to 43%; p < 0.001) fewer patients who reached the beginning of the growth plateau than those indicated by U7/8, and it identified 39% fewer patients than SS6/7 (95% CI 32% to 47%; p < 0.001). For boys, similarly, R8/9, U7/8, and SS6/7 were all more effective than Risser stage 4 in identifying when the growth plateau began. CONCLUSION: Risser stage 0+ corresponds to a wide range of Sanders and distal radius and ulna grades. Risser stage 0+ is least effective in indicating the peak growth in boys, and Risser stage 4 is the least effective maturity grade for indicating when the growth plateau starts in both sexes. The concurrent use of R6 and SS3 can be useful for detecting the peak growth, and SS6/7 in conjunction with U7/8 is most effective in indicating the beginning of the growth plateau. Using a combination of specific grades of Sanders staging and the distal radius and ulna classification can indicate pubertal growth landmarks with reduced risk of underestimating or overestimating skeletal maturity. These findings may aid in refining clinical decision-making of brace initiation and weaning at a more precise timing. Among Risser stage 0, the appearance of R6, U5, and SS3 provide the most effective assessment of peak growth that can indicate the most effective bracing period within which curve progression occurs. For initiation of the growth plateau, Risser 4 is not useful, and SS6/7, R8/9 and U7/8 should be used instead. LEVEL OF EVIDENCE: Level III, diagnostic study.

Curve Progression in Adolescent Idiopathic Scoliosis Does Not Match Skeletal Growth.

BACKGROUND: Determining the peak growth velocity of a patient with adolescent idiopathic scoliosis (AIS) is important for timely treatment to prevent curve progression. It is important to be able to predict when the curve-progression risk is greatest to maximize the benefits of any intervention for AIS. The distal radius and ulna (DRU) classification has been shown to accurately predict skeletal growth. However, its utility in predicting curve progression and the rate of progression in AIS is unknown. QUESTIONS/PURPOSES: (1) What is the relationship between radius and ulna grades to growth rate (body height and arm span) and curve progression rate? (2) When does peak curve progression occur in relation to peak growth rate as measured by months and by DRU grades? (3) How many months and how many DRU grades elapse between peak curve progression and plateau? METHODS: This was a retrospective analysis of a longitudinally maintained dataset of growth and Cobb angle data of patients with AIS who presented with Risser Stages 0 to 3 and were followed to maturity at Risser Stage 5 at a single institute with territory-wide school screening service. From June 2014 to March 2016, a total of 513 patients with AIS fulfilled study inclusion criteria. Of these, 195 were treated with bracing at the initial presentation and were excluded. A total of 318 patients with AIS (74% girls) with a mean age of 12 ± 1.5 years were studied. For analysis, only data from initial presentation to commencement of intervention were recorded. Data for patients during the period of bracing or after surgery were not used for analysis to eliminate potential interventional confounders. Of these 318 patients, 192 were observed, 119 were braced, and seven underwent surgery. Therefore 192 patients (60.4%) who were observed were followed up until skeletal maturity at Risser Stage 5; no patients were lost to followup. The mean curve magnitude at baseline was 21.6 ± 4.8. Mean followup before commencing intervention or skeletal maturity was 4.3 ± 2.3 years. Standing body height, arm span, curve magnitude, Risser stage, and DRU classification were studied. A subgroup analysis of 83 patients inclusive of acceleration, peak, and deceleration progression phases for growth and curve progression was studied to determine any time lag between growth and curve progression. Results were described in mean ± SD. RESULTS: There was positive correlation between growth rate and curve progression rate for body height (r = 0.26; p < 0.001) and arm span (r = 0.26; p < 0.001). Peak growth for body height occurred at radius grade (R) 6 (0.56 ± 0.29 cm/month) and ulna grade (U) 4 (0.65 ± 0.31 cm/month); peak change in arm span occurred at R5 (0.67 ± 0.33 cm/month) and U3 (0.67 ± 0.22 cm/month); and peak curve progression matched with R7 (0.80 ± 0.89 cm/month) and U5 (0.84 ± 0.78 cm/month). Subgroup analysis confirmed that peak curve progression lagged behind peak growth rate by approximately 7 months or one DRU grade. The mean time elapsed between the peak curve progression rate and the plateau phase at R9 U7 was approximately 16 months, corresponding to two DRU grades. CONCLUSIONS: By using a standard skeletal maturity parameter in the DRU classification, this study showed that the maximal curve progression occurs after the peak growth spurt, suggesting that the curve should be monitored closely even after peak growth. In addition, the period of potential curve continuing progression extends nearly 1.5 years beyond the peak growth phase until skeletal maturity. Future studies may evaluate whether by observing the trend of growth and curve progression rates, we can improve the outcomes of interventions like bracing for AIS. LEVEL OF EVIDENCE: Level II, prognostic study.

Ulna Growth Patterns After Soft Tissue Release With Bilobed Flap in Radial Longitudinal Deficiency.

BACKGROUND: Centralization is commonly utilized for treating the severely deviated wrist in radial longitudinal deficiency (RLD). Individuals with RLD have congenital shortening of the ulna and previous studies have shown that traditional centralization, in particular with notching of the carpus, results in additional ulnar growth retardation. At our institution, we use a technique of soft tissue release with bilobed flap. We examined if this technique preserves the growth potential of the distal ulna, therefore, avoiding an additionally shortened forearm. METHODS: We retrospectively reviewed serial radiographs of 16 patients with 18 wrists who had at least 3 years of follow-up after a soft tissue release with bilobed flap. Radiographic lengths were measured using the method described by Heikel. Percentage of normal growth was calculated using normative data published by Maresh. Comparisons were made with preoperative, postoperative, and final follow-up studies. RESULTS: The average length of follow-up was 9.2 years (range, 3 to 16.3 y) with an average age of 11.6 years (range, 5.2 to 17.5 y). The average age at the time of surgery was 27 months (range, 14 to 48 mo). A minimum of 3 radiographic studies were available for each subject. The average ulna length preoperatively was 63.9% of age-matched normal length (51.4% to 75.3%). The average ulna length at final follow-up was 61.9% of age-matched normal length (48.5% to 70.3%). The difference was not statistically significant. In addition, there were no distal ulnar physeal arrests. CONCLUSIONS: Soft tissue release with bilobed flap does not affect ulna growth like traditional centralization procedures can. This procedure has previously been shown to retain motion and have similar recurrence rates to formal centralizations. Therefore, we advocate that it be considered more widely for use in patients with RLD and significant wrist deviation to maximize growth and improve hand position. Soft tissue release with bilobed flap can be safely used on young children and preserve ulnar growth. LEVEL OF EVIDENCE: Level IV-therapeutic.

Acquired Upper Extremity Growth Arrest.

This study reviewed the clinical history and management of acquired growth arrest in the upper extremity in pediatric patients. The records of all patients presenting from 1996 to 2012 with radiographically proven acquired growth arrest were reviewed. Records were examined to determine the etiology and site of growth arrest, management, and complications. Patients with tumors or hereditary etiology were excluded. A total of 44 patients (24 boys and 20 girls) with 51 physeal arrests who presented at a mean age of 10.6 years (range, 0.8-18.2 years) were included in the study. The distal radius was the most common site (n=24), followed by the distal humerus (n=8), metacarpal (n=6), distal ulna (n=5), proximal humerus (n=4), radial head (n=3), and olecranon (n=1). Growth arrest was secondary to trauma (n=22), infection (n=11), idiopathy (n=6), inflammation (n=2), compartment syndrome (n=2), and avascular necrosis (n=1). Twenty-six patients (59%) underwent surgical intervention to address deformity caused by the physeal arrest. Operative procedures included ipsilateral unaffected bone epiphysiodesis (n=21), shortening osteotomy (n=10), lengthening osteotomy (n=8), excision of physeal bar or bone fragment (n=2), angular correction osteotomy (n=1), and creation of single bone forearm (n=1). Four complications occurred; 3 of these required additional procedures. Acquired upper extremity growth arrest usually is caused by trauma or infection, and the most frequent site is the distal radius. Growth disturbances due to premature arrest can be treated effectively with epiphysiodesis or osteotomy. In this series, the specific site of anatomic growth arrest was the primary factor in determining treatment. [Orthopedics. 2017; 40(1):e95-e103.].

A new formula for assessing skeletal age in growing infants and children by measuring carpals and epiphyses of radio and ulna.

The aim of this study is to develop a specific formula for the purpose of assessing skeletal age in a sample of Italian growing infants and children by measuring carpals and epiphyses of radio and ulna. A sample of 332 X-rays of left hand-wrist bones (130 boys and 202 girls), aged between 1 and 16 years, was analyzed retrospectively. Analysis of covariance (ANCOVA) was applied to study how sex affects the growth of the ratio Bo/Ca in the boys and girls groups. The regression model, describing age as a linear function of sex and the Bo/Ca ratio for the new Italian sample, yielded the following formula: Age = -1.7702 + 1.0088 g + 14.8166 (Bo/Ca). This model explained 83.5% of total variance (R(2) = 0.835). The median of the absolute values of residuals (observed age minus predicted age) was -0.38, with a quartile deviation of 2.01 and a standard error of estimate of 1.54. A second sample test of 204 Italian children (108 girls and 96 boys), aged between 1 and 16 years, was used to evaluate the accuracy of the specific regression model. A sample paired t-test was used to analyze the mean differences between the skeletal and chronological age. The mean error for girls is 0.00 and the estimated age is slightly underestimated in boys with a mean error of -0.30 years. The standard deviations are 0.70 years for girls and 0.78 years for boys. The obtained results indicate that there is a high relationship between estimated and chronological ages.

Elevated mechanical loading when young provides lifelong benefits to cortical bone properties in female rats independent of a surgically induced menopause.

Exercise that mechanically loads the skeleton is advocated when young to enhance lifelong bone health. Whether the skeletal benefits of elevated loading when young persist into adulthood and after menopause are important questions. This study investigated the influence of a surgically induced menopause in female Sprague-Dawley rats on the lifelong maintenance of the cortical bone benefits of skeletal loading when young. Animals had their right forearm extrinsically loaded 3 d/wk between 4 and 10 weeks of age using the forearm axial compression loading model. Left forearms were internal controls and not loaded. Animals were subsequently detrained (restricted to cage activities) for 94 weeks (until age 2 years), with ovariectomy (OVX) or sham-OVX surgery being performed at 24 weeks of age. Loading enhanced midshaft ulna cortical bone mass, structure, and estimated strength. These benefits persisted lifelong and contributed to loaded ulnas having greater strength after detraining. Loading also had effects on cortical bone quality. The benefits of loading when young were not influenced by a surgically induced menopause because there were no interactions between loading and surgery. However, OVX had independent effects on cortical bone mass, structure, and estimated strength at early postsurgery time points (up to age 58 weeks) and bone quality measures. These data indicate skeletal loading when young had lifelong benefits on cortical bone properties that persisted independent of a surgically induced menopause. This suggests that skeletal loading associated with exercise when young may provide lifelong antifracture benefits by priming the skeleton to offset the cortical bone changes associated with aging and menopause.

Ulnar shortening for adolescent ulnar impaction syndrome: radiological and clinical outcomes.

PURPOSE: To determine the amount of shortening needed in an ulna to achieve final neutral ulnar variance in adolescents with ulnar impaction syndrome. Radiological and clinical outcomes were evaluated after ulnar shortening and after growth had stopped. METHODS: From February 2006 to February 2009, we prospectively followed 16 consecutive patients treated with a shortening osteotomy for positive ulnar variance. The study group included 10 boys and 6 girls with an average age of 16.1 years. The closed medial half-side of the physis of the distal radius was used to measure the variance as a reference for the ulna. Based on the radius without any growth potential, the amount of shortening was determined for the ulna with potential for further growth. The preoperative, postoperative, and final ulnar variances were evaluated. The clinical results were compared before surgery and at the time of growth termination. RESULTS: Preoperative ulnar variance was 3.4 mm ± 0.6 mm and the amount to be shortened was 6.1 mm ± 1 mm. The final ulnar variance was 0.2 mm ± 0.3 mm. The mean visual analog scale pain score improved from 6.6 ± 1.0 before surgery to 2.2 ± 0.5 after surgery. The mean range of forearm rotation increased from 132° ± 11° before surgery to 170° ± 16° at final follow-up. In addition, grip strength was 15.3 kg ± 7.6 kg (71% of grip strength on the unaffected side) before surgery and 19.8 kg ± 4.9 kg (90% of grip strength on the unaffected side) at final follow-up. The modified Mayo Wrist Score was 85 ± 8 at the final follow-up. No cases of complications or treatment failure occurred. CONCLUSIONS: Ulnar shortening was considered a useful procedure for adolescents with ulnar impaction syndrome, particularly if the measurement for the shortening amount was determined using the physis of the distal radius and ulna.

Functional adaptation in female rats: the role of estrogen signaling.

BACKGROUND: Sex steroids have direct effects on the skeleton. Estrogen acts on the skeleton via the classical genomic estrogen receptors alpha and beta (ERα and ERß), a membrane ER, and the non-genomic G-protein coupled estrogen receptor (GPER). GPER is distributed throughout the nervous system, but little is known about its effects on bone. In male rats, adaptation to loading is neuronally regulated, but this has not been studied in females. METHODOLOGY/PRINCIPAL FINDINGS: We used the rat ulna end-loading model to induce an adaptive modeling response in ovariectomized (OVX) female Sprague-Dawley rats. Rats were treated with a placebo, estrogen (17ß-estradiol), or G-1, a GPER-specific agonist. Fourteen days after OVX, rats underwent unilateral cyclic loading of the right ulna; half of the rats in each group had brachial plexus anesthesia (BPA) of the loaded limb before loading. Ten days after loading, serum estrogen concentrations, dorsal root ganglion (DRG) gene expression of ERα, ERß, GPER, CGRPα, TRPV1, TRPV4 and TRPA1, and load-induced skeletal responses were quantified. We hypothesized that estrogen and G-1 treatment would influence skeletal responses to cyclic loading through a neuronal mechanism. We found that estrogen suppresses periosteal bone formation in female rats. This physiological effect is not GPER-mediated. We also found that absolute mechanosensitivity in female rats was decreased, when compared with male rats. Blocking of adaptive bone formation by BPA in Placebo OVX females was reduced. CONCLUSIONS: Estrogen acts to decrease periosteal bone formation in female rats in vivo. This effect is not GPER-mediated. Gender differences in absolute bone mechanosensitivity exist in young Sprague-Dawley rats with reduced mechanosensitivity in females, although underlying bone formation rate associated with growth likely influences this observation. In contrast to female and male rats, central neuronal signals had a diminished effect on adaptive bone formation in estrogen-deficient female rats.

Growth potential of different zones of the growth plate-an experimental study in rabbits.

Despite clinical efforts to treat growth disturbances only little is known about the growth potential of the different zones of the growth plate. The aim of this study was to investigate the growth potential of different zones of the growth plate. A total of 20 New Zealand White rabbits were used for this experiment. The right and left ulna of each animal were used resulting in a total of 40 ulnae. Animals were assigned into five groups. In groups I and II resection of the metaphyseal (n = 12) or the epiphyseal (n = 6) segment of the growth plate was performed. In group III resection of the growth plate and re-implantation was performed (n = 6). In group IV the growth plate was resected and re-implanted after a 180° rotation (n = 6). Animals in group V served as controls. Histologic and radiologic examinations were performed to evaluate the growth process at 1, 2, 4, and 12 weeks following surgery. In group I, III, and IV temporary growth disturbance which was compensated within a short time was observed. Resection of the epiphyseal part resulted in growth arrest of the distal ulna in combination with normal growth of the radius which led to and valgus deformity of the limb. The results of this study indicate the importance of the reserve zone for the functioning of the growth plate.

Developmental anterior dislocation of the radial head resulting from a congenital solitary osteochondroma of the proximal ulna in an infant.

A 4-month-old female infant was brought to our office by her parents, who had noticed a lump on the child's right elbow. Examination revealed a hard, painless lump in the antero-external region that was not reducible in flexion-extension or in pronation-supination. Neither palpation nor passive motion produced pain. Preoperative radiographs revealed a bony mass in the anteroexternal region of the proximal ulnar metaphysic (solitary osteochondroma), which was displacing the radial head into anteroexternal dislocation. No physiological bowing of the proximal metaphysis of the ulna was present. The infant underwent surgery at 6 months of age. No remains of the annular ligament were found. A complete resection of the tumour mass was performed, after which it was possible to reduce the radial head, together with the humeral condyle. Trans-radiocapitellar fixation was applied, with immobilization for 6 weeks. Subsequent radiological study revealed a congruent reduction of the radial head, with a progressive periosteal reaction of the posterior cortex of the ulna that evolved towards remodeling of the physiological bowing. Eight years after the surgery, the child remains asymptomatic, with complete range of motion and symmetric carrying angles. There were no relapses of osteochondroma, the deformity, or radioulnar synostosis.

Ulnar metaphyseal osteochondrosis in seven captive bred cheetahs (Acinonyx jubatus).

Distal ulna metaphyseal osteochondrosis was identified in seven captive bred cheetahs raised in Australia between 1984 and 2005. The disorder was characterized by bilateral carpal valgus conformation. In the metaphyseal region of the distal ulnae, an osteolucent defect that appeared as a proximal extension of the lucent physis was identified radiographically between 6 and 10 months of age. Ulna ostectomy was done to correct the angular limb deformity. Histologically, changes were identified in the osteolucent lesion that resembled osteochondrosis. We propose that the condition is probably familial and/or dietary in origin.

Treatment of radial dysplasia by a combination of distraction, radialisation and a bilobed flap - the results at 5-year follow-up.

Thirty-nine hands with radial dysplasia were prospectively treated between 1998 and 2005 by a combination of distraction, followed by radialisation, using bilobed flaps to redistribute the skin at the wrist. Correction of radial deviation and volar subluxation in 29 hands with an average follow-up of 6.5 years has been assessed. In 21 hands, the length and breadth of the ulna were measured in the corrected hands and compared to the contralateral normal ulna for length and contralateral normal radii for breadth at 5-year follow-up. The average length of the ulna was 72%, which was notably better than that reported in earlier series.

Skeletal age assessment from the olecranon for idiopathic scoliosis at Risser grade 0.

BACKGROUND: The main progression of idiopathic scoliosis occurs during peak height growth velocity, which is between the ages of eleven and thirteen years in girls and thirteen and fifteen years in boys and corresponds to the accelerating phase of pubertal growth. The Risser sign remains at grade 0 during this stage of growth. Triradiate cartilage closure occurs at approximately twelve years of age in girls and fourteen years in boys, which is in the middle of this phase. In addition to regular height measurements, a more detailed evaluation of skeletal maturity would be desirable prior to the identification of Risser grade 1. From the method of Sauvegrain et al., Diméglio derived a simplified method based on the radiographic appearance of the olecranon, which allows skeletal age to be assessed in six-month intervals. The purpose of this study was to determine the accuracy and the value of this simple method for the follow-up of patients with scoliosis. METHODS: Five radiographic images demonstrate the typical characteristics of the olecranon during pubertal growth: two ossification nuclei, a half-moon image, a rectangular shape, the beginning of fusion, and complete fusion. This classification method was evaluated by three experienced and independent observers from lateral radiographs of the elbow in 100 boys and 100 girls with idiopathic scoliosis during the time of peak height velocity. Skeletal ages were correlated with the integral Sauvegrain method. The degree of interobserver concordance was determined, and skeletal age was compared with chronological age and the time of triradiate cartilage closure. RESULTS: For the three observers, the average concordance between the Sauvegrain and olecranon methods was excellent (r = 0.977 for boys and r = 0.938 for girls). The interobserver agreement was also excellent (r = 0.987 for the olecranon method and r = 0.958 for the Sauvegrain method for boys, and r = 0.992 and r = 0.985, respectively, for girls). Skeletal and chronological age were considered to correspond to each other within a six-month range for 49% of the boys and 51% of the girls, while 25% of the boys and 26% of the girls had an advanced skeletal age and 26% of boys and 23% of girls had a delayed skeletal age. Triradiate cartilage closure occurred at the same time as the appearance of the rectangular shape of the olecranon in 65% of the boys and 61% of the girls, corresponding to skeletal ages of fourteen and twelve years, respectively. In 91% of the boys and 88% of the girls, the triradiate cartilage fused within six months before to six months after the appearance of the rectangular shape of the olecranon, which occurred between the half-moon image and the beginning of fusion of the olecranon. CONCLUSIONS: The method of assessing skeletal age from the olecranon allows skeletal maturity to be evaluated in regular six-month intervals during the phase of peak height velocity. This method is simple, precise, and reliable. It complements the Risser grade-0 and the triradiate cartilage evaluation.

A new type of radiographic bone remodeling in the distal radial and ulnar metaphysis in 54 Newfoundland dogs.

In this longitudinal observational study, 118 growing Newfoundland dogs were followed with sequential radiographic examination of the right front limb, which were scheduled at ages 3, 4, 6, 12, 18, and 24 months to record evidence of skeletal changes. All affected dogs had evidence of changes at 6 months and dogs included in this study had radiographic examination at 6 months and at least two other scheduled examinations that included either 4 or 12 months. The dogs were privately owned and had individualized nutrition and environment with no maintenance protocol required by the project leaders. Irregularities in bone remodeling in the distal radius and ulna were seen in radiographs of 54 of 118 (45.8%) dogs. These irregularities differ from changes previously described in the Newfoundland dog. The reported irregularities were seen as islands of reduced opacity outlined by thickened, radiopaque osseous trabeculae, which were aligned with the axis of stress. All the 54 dogs with irregularities during some phase of development consistently had changes at 6 months of age. Reorganization of the changes in the bone was slow, and residual changes were visible at 18-24 months of age in many cases. The significance of these findings may lie in their potential for misinterpretation if they had been discovered in the presence of clinical signs such as any lameness or growth arrest. Radiographic appearance indicates disturbances in the bone maturation. The etiopathogenesis is unclear. Nutritional, environmental and genetic factors have to be studied.

Ulnar focal cortical indentation: a previously unrecognised form of ulnar dysplasia.

Deformity of the forearm due to growth disturbance of the ulna occurs in a number of conditions such as ulnar deficiency, multiple exostoses, and neurofibromatosis. We report a previously unrecognised form, caused by focal cortical indentation. We have treated five children with this condition, three girls and two boys; the mean age at presentation was 5 years (2 to 8). The deformity was first recognised about the age of two years, and progressed gradually. The radiological findings were the same in all cases. The focal cortical indentation was seen at the distal end of the ulna with anteromedial bowing and dysplasia. The radial head was dislocated posterolaterally. In one patient the histological findings at the site of indentation were of a fold of tissue resembling periosteum, which interfered with enchondral ossification. Treatment by ulnar lengthening using an external fixator and osteotomy which corrected both the ulnar deformity and reduced the dislocated radial head in two cases gave the best results.

Wrist anomalies in Turner syndrome compared with Leri-Weill dyschondrosteosis: a new feature in Turner syndrome.

UNLABELLED: We analysed bone age radiographs in 102 girls with Turner syndrome and compared the findings with 93 control girls and nine girls with Leri-Weill syndrome. Various signs were analysed: radial bowing or Madelung deformity, maximal/minimal height of the radial epiphysis, brachymetacarpia of the 4th digit, carpal and epiphyseal angle, as well as a new sign the distal radio-ulnar physeal disparity. Two values differed significantly between the Turner group and the control group, the first being the epiphyseal angle which has already been reported to be greater in Turner syndrome, and the second being the new sign we have been able to describe. Turner patients had an increased distance between the ulnar and radial metaphysis, or "distal radio-ulnar physeal disparity", the ulnar being shorter. Furthermore, in 27% of cases the medial extremity of the ulnar epiphysis was flattened and passed below the distal extremity of the radius, whose medial part projected over the distal extremity of the ulna, thus reproducing in reverse the characteristic feature of Leri-Weill syndrome. In the growth hormone-treated Turner patients, we found a significant correlation between distal radio-ulnar physeal disparity and growth velocity expressed in cm/year (r = 0.28; P < 0.002) or in SDS/bone age (r = 0.21; P < 0.03) during the first year of treatment. CONCLUSION: the value of this new sign requires further investigation.

Multiple roles of Hoxa11 and Hoxd11 in the formation of the mammalian forelimb zeugopod.

Mutations in the 5' or posterior murine Hox genes (paralogous groups 9-13) markedly affect the formation of the stylopod, zeugopod and autopod of both forelimbs and hindlimbs. Targeted disruption of Hoxa11 and Hoxd11 or Hoxa10, Hoxc10 and Hoxd10 result in gross mispatterning of the radius and ulna or the femur, respectively. Similarly, in mice with disruptions of both Hoxa13 and Hoxd13, development of the forelimb and hindlimb autopod is severely curtailed. Although these examples clearly illustrate the major roles played by the posterior Hox genes, little is known regarding the stage or stages at which Hox transcription factors intersect with the limb development program to ensure proper patterning of the principle elements of the limb. Moreover, the cellular and/or molecular bases for the developmental defects observed in these mutant mice have not been described. In this study, we show that malformation of the forelimb zeugopod in Hoxa11/Hoxd11 double mutants is a consequence of interruption at multiple steps during the formation of the radius and ulna. In particular, reductions in the levels of Fgf8 and Fgf10 expression may be related to the observed delay in forelimb bud outgrowth that, in turn, leads to the formation of smaller mesenchymal condensations. However, the most significant defect appears to be the failure to form normal growth plates at the proximal and distal ends of the zeugopod bones. As a consequence, growth and maturation of these bones is highly disorganized, resulting in the creation of amorphous bony elements, rather than a normal radius and ulna.

Fractures of the olecranon during growth: a 15-25-year follow-up.

Ten girls and 13 boys with mean age 11 years when sustaining a fracture of the olecranon were examined at a mean of 19 years after the injury. Ten fractures were displaced less than 2 mm, three 2-3 mm, eight more than 3 mm and two were multifragmental. The treatment consisted of mobilization in three cases, plaster treatment in nine and open reduction and internal fixation in 11 cases. At follow-up, 21 children had no subjective complaints while two had occasional mild pain. The upper arm circumference was thinner in the former injured extremities than in the uninjured (P<0.05). No other objective deficits were found. None had developed non-union or elbow osteoarthritis. Olecranon fractures during growth have an excellent long-term outcome.