Mandar Vikas Agashe

Comparison between upper and lower limb lengthening in patients with achondroplasia: a retrospective study

Lengthening of the humerus is now an established technique. We compared the complications of humeral lengthening with those of femoral lengthening and investigated whether or not the callus formation in the humerus proceeds at a higher rate than that in the femur. A total of 24 humeral and 24 femoral lengthenings were performed on 12 patients with achondroplasia. We measured the pixel value ratio (PVR) of the lengthened area on radiographs and each radiograph was analysed for the shape, type and density of the callus. The quality of life (QOL) of the patients after humeral lengthening was compared with that prior to surgery. The complication rate per segment of humerus and femur was 0.87% and 1.37%, respectively. In the humerus the PVR was significantly higher than that of the femur. Lower limbs were associated with an increased incidence of concave, lateral and central callus shapes. Humeral lengthening had a lower complication rate than lower-limb lengthening, and QOL increased significantly after humeral lengthening. Callus formation in the humerus during the distraction period proceeded at a significantly higher rate than that in the femur. These findings indicate that humeral lengthening has an important role in the management of patients with achondroplasia.

New proposed clinico‐radiologic and molecular criteria in hypochondroplasia: FGFR 3 gene mutations are not the only cause of hypochondroplasia

We applied a comprehensive set of clinical and radiological criteria for the diagnosis of hypochondroplasia (HCH) in 160 patients with short stature 58 of whom were diagnosed to have HCH. Taking into account the genotypic and phenotypic variations in HCH, we conducted a study with these 58 patients and tested them for mutations in the fibroblast growth factor receptor 3 (FGFR3) and the short stature homeobox (SHOX) gene. We characterized the phenotypes by clinical and radiologic findings. In the patients with HCH, 19 were included in Group I (FGFR3 mutations—mutations of definite significance), and 39 were in Group II (6 SHOX mutations and 33 negative for disease‐causing FGFR3 mutations). The clinical findings were similar in two groups regardless of the presence or absence of mutations. More than 95% of the patients had mesomelic proportions. In Group I, the radiological findings of mesomelia of upper and lower limbs and, L1/L4 ratio in anterior–posterior and lateral view were more typical than in Group II. This study proposes comprehensive clinico‐radiological criteria for the diagnosis of HCH, which would help in detecting the true incidence of this underdiagnosed condition. The presence of SHOX mutations suggest genotypic–phenotypic overlap between HCH and Leri–Weill dyschondrosteosis, though further investigation is needed to effectively elucidate the importance of these mutations. Also, the 56.9% of HCH patients with negative mutations for FGFR3 suggests that there are other undiscovered gene mutations associated with this phenotypic entity.

Reliability of Overcoverage Parameters With Varying Morphologic Pincer Features: Comparison of EOS ® and Radiography

BackgroundMultiple radiographic parameters used for diagnosis and quantification of morphologic pincer features have emerged, but the degree to which pelvic tilt or rotation affects conventional radiography and EOS® is unknown.Question/purposesWe asked: (1) What is the reliability of EOS® and conventional radiography at increasing sizes of morphologic pincer features with varying degrees of tilt and rotation? (2) What is the effect of tilt and rotation on acetabular overcoverage measurements?MethodsUsing a dry cadaveric pelvis, AP conventional radiographs and EOS® images were taken at intervals of increasing modeled pincer size with 0° to 15° varying tilt and rotation. Lateral center-edge angle, Sharp angle, Tönnis angle, crossover sign, and retroversion index were measured on all images. Statistical analysis was conducted.ResultsThe intermodality intraclass correlation coefficients for conventional radiography and EOS® radiography across all pincer sizes, rotations, and tilts were excellent (0.93–0.98). Crossover sign was in perfect agreement in conventional radiography and EOS®. Rotation of the hip away from the beam source and/or increased anterior tilt falsely increased all overcoverage parameters except for Tönnis angle. Rotation away from the beam of 10°or greater or anterior tilt of 5° or greater produced a false-positive crossover sign.ConclusionsEOS® radiography maintained excellent reliability in comparison to conventional radiography but both were equally vulnerable to the effects of tilt and rotation for quantification of hip parameters used in acetabular overcoverage assessment. A standardized pelvic radiograph ensuring that the pelvis is not excessively tilted or rotated should be used for assessing acetabular overcoverage parameters.

Congenital pseudarthrosis of the tibia treated with a combination of Ilizarov's technique and intramedullary rodding.

Background and purpose Ilizarov’s technique and intramedullary rodding have often been used individually in congenital pseudarthrosis of the tibia. In this series, we attempted to combine the advantages of both methods while minimizing the complications. Methods We reviewed 15 cases of congenital pseudoarthrosis of the tibia (CPT) who were treated with a combination of Ilizarov’s apparatus and antegrade intramedullary nailing between 2003 and 2008. The mean age at surgery was 7.5 (3–12) years and the mean limb length discrepancy was 2.5 (1.5–5) cm. At a mean follow-up time of 4.5 (1.6–7.2) years after the index surgery, the patients were evaluated clinically and radiographically for ankle function (AOFAS score) and for malalignment, signs of union, limb length discrepancy, and complications. Results 14 patients achieved union, in 6 patients primary union and in 8 patients after secondary procedures. The AOFAS score improved from a preoperative mean of 40 (20–57) to 64 (47–75). The main complication was refracture in 1 patient, and non-union in 1 patient. Interpretation The combination of the Ilizarov technique and conventional antegrade intramedullary nailing was successful in achieving union with few complications, though this should be shown in long-term studies lasting until skeletal maturity.

Serial bone mineral density ratio measurement for fixator removal in tibia distraction osteogenesis and need of a supportive method using the pixel value ratio

Distraction osteogenesis is one of the common procedures for limb lengthening. However, attempts are being made constantly to establish objective guidelines for early and safe removal of a fixator using a sensitive and quantitative measurement technique. Dual-energy X-ray absorptiometry (DEXA) has been evaluated in the past for understanding callus stiffness, and the present study is a step further in this direction. The purpose of this study was to evaluate the correlation between bone mineral density ratio (BMDR) obtained by a DEXA scan and the pixel value ratio (PVR) on plain digital radiographs at each cortex and various callus pathways and callus shapes as described by Ru-Li’s classification. A retrospective analysis of 40 tibial segments in 23 patients operated upon for various indications for limb lengthening was carried out. There were 11 male and 12 female patients with a mean age of 18 years. The Ilizarov method was applied after monofocal osteotomy, and distraction and consolidation were monitored using digital radiographs and DEXA scanning. BMDR was positively correlated with PVR, and the optimal BMDR for removal of the fixator was found to be 0.511. PVR of all cortices, except the anterior cortex, showed significant positive correlation with BMDR of the regenerate. There was good correlation between BMDR and PVR in the homogenous or heterogenous pathway according to callus shape and pathway. Thus, this study shows that BMD measurement can provide an objective and noninvasive method for assessing the rate of new bone formation during tibial distraction osteogenesis. It can thus function as an effective adjunct to measure callus stiffness, along with PVR, using digital radiographs, especially in cases in which callus maturation and stiffness is doubtful. Further studies especially dealing with callus progression through the lucent pathway as well as those dealing with regenerate fractures may be needed to conclusively prove the efficacy of this method for measurement of callus maturation.

Subtrochanteric valgus osteotomy with monolateral external fixator in hips for patients with severe cerebral palsy.

Subtrochanteric valgus osteotomy has been used for painful hip joint dislocation in patients with severe cerebral palsy. The goal of this study was to evaluate 11 patients (17 hips) with severe cerebral palsy who had chronically dislocated and painful hips treated with subtrochanteric valgus osteotomy using a monolateral external fixator. A retrospective review was performed of 11 patients (average age, 17.8 years) with severe quadriplegic cerebral palsy with flexion-adduction contractures due to chronically dislocated and painful hips. A subtrochanteric valgus osteotomy with a monolateral fixator was performed in all patients. Patients were analyzed clinicoradiologically, and caregivers were asked about ease of handling, transfers, and perineal care. At an average follow-up of 37 months (range, 14-72 months), all caregivers were satisfied with the surgery and felt that their child was more comfortable and could sit with support for a longer time period and that perineal care, wheelchair mobilization, and transfers were much easier. A total of 11 complications in 7 patients were observed, including pin-tract infections, delayed consolidation, abduction deformity, and hypostatic pneumonia. The complication rate of subtrochanteric valgus osteotomy was comparable with other methods, and this method had the advantage of shorter surgical time, ease of application, no internal implant with lesser chance of infection or heterotopic calcification, and less intraoperative blood loss with less morbidity.

Fibula-related complications during bilateral tibial lengthening: 60 patients followed for mean 5 years

Background and purpose Complications related to the fibula during distraction osteogenesis could cause malalignment. Most published studies have analyzed only migration of the fibula during lengthening, with few studies examining the effects of fibular complications. Patients and methods We retrospectively reviewed 120 segments (in 60 patients) between 2002 and 2009. All patients underwent bilateral tibial lengthening of more than 5 cm. The mean follow-up time was 4.9 (2.5–6.9) years. Results The average lengthening percentage was 34% (21–65). The ratio of mean fibular length to tibial length was 1.05 (0.91–1.11) preoperatively and 0.83 (0.65–0.95) postoperatively. The mean proximal fibular migration (PFM) was 15 (4–31) mm and mean distal fibular migration (DFM) was 9.7 (0–24) mm. Premature consolidation occurred in 10 segments, nonunion occurred in 12, and angulation of fibula occurred in 8 segments after lengthening. Valgus deformities of the knee occurred in 10 segments. Interpretation PFM induced valgus deformity of the knee, and premature consolidation of the fibula was associated with the distal migration of the proximal fibula. These mechanical malalignments could sometimes be serious enough to warrant surgical correction. Thus, during lengthening repeated radiographic examinations of the fibula are necessary to avoid complications.

Paravertebral ligament ossification in vitamin D-resistant rickets: incidence, clinical significance, and genetic evaluation.

Study Design. A retrospective observational study. Objective. The objective of this study was to analyze the cases of paravertebral ossification in vitamin D–resistant rickets (VDRR) and elucidate its incidence and clinical significance, and report specific genetic mutations uniquely associated with this phenomenon. Summary of Background Data. Paravertebral ligament ossification has been described in VDRR in a few cases previously. However, supraspinous and interspinous ligament ossification has so far not been described to occur in association with VDRR. We reviewed 6 cases of paravertebral ligament ossification with the added feature of supraspinous and interspinous ligament calcification. Methods. Forty-four patients with clinical, radiological, and biochemical diagnoses of VDRR, who were positive for mutations in the PHEX gene, were screened for the presence of paravertebral ossification with plain radiographs and computed tomography/magnetic resonance imaging if necessary. This was correlated with the severity of disease, and we looked for specific genetic mutations. Results. Six patients had paravertebral ligament ossification, which included supraspinous and interspinous ligament ossification. These patients had a more severe systemic disease, with all patients requiring at least 1 surgery for deformity correction of the limbs, with a total of 10 surgical procedures performed in these 6 patients. c.1601C>T, c.1699C>T, c.1363G>T, and c.466_467insAC were the genetic mutations associated with these cases. Conclusion. The spinal changes with paravertebral ligament ossification in VDRR were described in this study. Four different gene mutations related to the PHEX gene were detected in them. The presence of these changes was suggestive of a more severe systemic disease.

Convergent radioulnar translocation with radial head fracture in a child: a case report and review of the literature.

SUMMARY Convergent type radioulnar translocation is an extremely rare form of injury occurring in a growing child. We report a case of convergent radioulnar translocation along with a radial head fracture in a young child. Open reduction of the elbow and internal fixation of the radial head fragment helped in achieving concentric reduction and good functional outcome at 2 years of follow-up. This case has been shown to highlight the diagnostic and management issues of this rare condition, which may be easily missed initially.

Physeal growth arrest after tibial lengthening in achondroplasia 23 children followed to skeletal maturity

Background and purpose Bilateral tibial lengthening has become one of the standard treatments for upper segment-lower segment disproportion and to improve quality of life in achondroplasia. We determined the effect of tibial lengthening on the tibial physis and compared tibial growth that occurred at the physis with that in non-operated patients with acondroplasia. Methods We performed a retrospective analysis of serial radiographs until skeletal maturity in 23 achondroplasia patients who underwent bilateral tibial lengthening before skeletal maturity (lengthening group L) and 12 achondroplasia patients of similar height and age who did not undergo tibial lengthening (control group C). The mean amount of lengthening of tibia in group L was 9.2 cm (lengthening percentage: 60%) and the mean age at the time of lengthening was 8.2 years. The mean duration of follow-up was 9.8 years. Results Skeletal maturity (fusion of physis) occurred at 15.2 years in group L and at 16.0 years in group C. The actual length of tibia (without distraction) at skeletal maturity was 238 mm in group L and 277 mm in group C (p = 0.03). The mean growth rates showed a decrease in group L relative to group C from about 2 years after surgery. Physeal closure was most pronounced on the anterolateral proximal tibial physis, with relative preservation of the distal physis. Interpretation Our findings indicate that physeal growth rate can be disturbed after tibial lengthening in achondroplasia, and a close watch should be kept for such an occurrence—especially when lengthening of more than 50% is attempted.