Lower Extremity Deformities Research Articles

A case report of twin reversed arterial perfusion sequence with expectant management

Acardiac twin or TRAP (twin reversed arterial perfusion) sequence is a rare complication of monochorionic pregnancies. In these cases, the heart is either absent or non-functional. It’s controversial whether conservative management or therapeutic treatment is better in TRAP-sequence. In this case, we present a 19-years old, primigravida diagnosed with spontaneous monochorionic monoamniotic twin pregnancy at 7th week of gestation. One of the fetuses had a crown-rump length of 8 mm and fetal heart rate 122/minute while the other one had a crown-rump of 7 mm with no detected fetal heartbeat. At the 11th week of gestation, the acardiac twin continued growing despite the absence of the fetal heart beat and fetal extremities. The cranium could not be evaluated clearly. The diagnosis of TRAP sequence was confirmed by the reversed direction of flow observed in the umbilical artery. Since the patient and her husband did not want any intervention, no interventional diagnostic and treatment modalities were applied. Preterm labor started at the 32th week. Because the presentations were transverse and breech, pump and acardiac fetus, respectively, a cesarean delivery was performed. A healthy female baby, weighing 1650 gr with APGAR scores of 9-10, first and fifth minutes, respectively, was delivered along with the acardiac fetus which was 1550 gram in weight, fetal heart beat negative, with upper and lower extremity deformities. The uniqueness of the present case is that there was no significant difference in the weight of both twins. The acardiac twin was as large as the pump twin. Except for twenty days hospitalization because of neonatal respiratory distress syndrome, which was a consequence of preterm labor, there were no problems with the pump twin even though managed conservatively. In monochorionic twin pregnancies, when one of the twins is found to be fetal heartbeat negative and it continues to grow with concomitant structural abnormalities, the TRAP sequence should come to mind. If the acardiac fetus is small and the pump fetus has no complications, the conservative approach can be considered. Our goal should be to deliver the pump twin with minimal complications. To achieve this, follow-ups and treatment should be individualized for each patient, the pump fetus should be monitored closely.

Idiopathic Genu Valgum and Its Association With Obesity in Children and Adolescents.

Obesity as a cause of lower extremity deformity in children has been well established. This deformity is most often seen as tibia vara, however, at our institution we have observed more obese children and adolescents over age 7 years with excessive or progressive idiopathic genu valgum. Our hypothesis is that children with idiopathic genu valgum have high rates of obesity which impact the severity of their disease. Retrospective review of existing data was performed on 66 consecutive children/112 limbs over age 7 years with idiopathic genu valgum, seen from 2010 to 2013. Children with known metabolic or skeletal disease were excluded. Genu valgum was defined as mechanical axis in zone II or III and mechanical tibiofemoral angle ≥4 degrees on standing anteroposterior radiograph of the lower extremities. Body mass index (BMI) was calculated and classified by Center for Disease Control percentiles. Skeletal maturation was rated by closure of pelvic and peri-genu physes. Severity of genu valgum was also assessed by femoral and tibial mechanical axes and the mechanical axis deviation. Mean patient age was 12.2±2.2 years. 47% of patients had BMI≥30 and 71% were categorized as obese (>95th percentile). No sex differences were identified. Skeletal maturation explained 25% of the variance in the mechanical axis deviation and 22% of the mechanical tibiofemoral angle. BMI predicted 9.8% of the tibial valgus. Because of its skewed distribution, BMI percentile was a less useful parameter for assessment. The 71% obesity rate found in our children with idiopathic genu valgum is significantly higher than the normal population. Higher BMI is associated with more tibial valgum but skeletal maturation was the main predictor of overall valgus severity. This suggests that obesity may play a role in the etiology of idiopathic genu valgum which progresses with skeletal maturation, thereby increasing the risk of osteoarthritis in adulthood. Level III.

Comparison of Transtibial Amputations in Diabetic Patients With and Without End-Stage Renal Disease.

The primary purpose of this retrospective study was to report on a consecutive series of 102 patients with diabetes mellitus (DM) who underwent transtibial amputation (TTA) for chronic infections and nonreconstructable lower extremity deformities. A secondary aim was to compare the outcomes of TTA patients with end-stage renal disease on dialysis (ESRD) to patients without ESRD, and to identify risk factors for mortality after TTA. This cohort involved a consecutive series of patients who were treated by a single surgeon. The TTA patients were divided into 2 groups for analysis. The study group included those patients with ESRD who underwent TTA, and the control group included those patients who did not have ESRD. At the time of final follow-up, 64 of 102 patients were ambulatory with a prosthesis. There was a significant improvement in ambulatory status after amputation (preoperatively 45.1%, postoperatively 62.7%, P = .02). Wound healing complications (infection and/or dehiscence) occurred in 31 of 102 patients and led to a transfemoral amputation in 4 patients. After TTA patients with ESRD were significantly more likely to die (52.4% vs. 23.5%, p <0.05) and significantly less like to ambulate (42.9% vs. 67.9%, p <0.05) than patients without ESRD. Contralateral foot problems after the TTA occurred in 33 of 97 patients and resulted in 10 patients undergoing a contralateral transtibial amputation. Excluding patients with bilateral amputations (5 prior to and 10 after the index amputation), 64 of 87 patients with successful unilateral transtibial amputations were able to ambulate with a prosthesis. Thirty of 102 patients (29.4%) died during the follow-up period, and 6 of these deaths occurred during the perioperative period (within 30 days of surgery). There were no significant differences between the 2 groups with regard to the use of staged TTA, need for transfemoral amputation, or wound healing problems at the amputation site. Patients who were unable to walk postoperatively had a calculated 5-year survival rate of 30.1%, whereas those who were ambulatory had a 5-year survival rate of 68.8%. Cox proportional hazards model demonstrated a 62% reduced risk of mortality in patients who were able to ambulate after LEA compared with those patients who were not able to ambulate. TTA in patients with diabetes was associated with substantial morbidity and mortality. Risk factors that were significantly associated with an increased rate of mortality were the presence of ESRD, age ≥56 years, and inability to ambulate postoperatively. Level III, retrospective case controlled study.

Our Results of Modified Sofield Procedure in Lower Extremity Deformities with Osteogenesis Imperfecta

Introduction: Osteogenesis Imperfecta (OI) is a connective tissue disorder, which is the most common cause of genetic osteoporosis characterized by long bone deformities and fractures. The key defect is the qualitative and quantitative lack of type I collagen. The primary target in these patients is to fix deformities and to prevent fractures. The surgical application is often a basic surgical technique known as “Shish Kebab” osteotomy and mainly based on the principle of multiple osteotomies, fixation, and intramedullary nailing. In the present study, we present our results of the modified Sofield procedure for osteogenesis imperfecta-related lower extremity deformities. Materials and methods: The study retrospectively examined 12 OI patients who were surgically treated between March 2006 and November 2011. The modified Sofield procedure was applied to a total of 29 lower extremity bones including 21 femurs and eight tibias. Double intramedullary K-wire and single K-wire were used in surgeries for the femur and the tibia, respectively. Results: The median age of the patients was 7 (range: 6 to 16) years. The mean follow-up was 3.18 (range: 1 to 5) years. The revision rate was 42.8% for femoral surgery, 62.5% for tibial surgery, and 48.2% for all surgery. The mean time of union was 47.3 (range: 30 to 60) days including 46.3 (range: 30 to 60) days for femoral, and 49.3 (range: 30 to 60) days for tibial surgeries. The mean time from one surgery to another was 58 (range: 4 to 96) months for femoral revision, and the mean time of tibial revision was 27.7 (range: 9 to 60) months. The mean time required for total revision was 28 (range: 4 to 96) months. The complication rate was 39% and 46% for femur and tibia, respectively. The overall complication rate was 41%. Conclusion: Our study results suggest that this method is an effective and reliable method in the surgical treatment of osteogenesis imperfecta, as it is easy to practice and access as well as being cost-effective. Although surgical treatment does not change the patient ambulation, it maintains mobilization, reducing the incidence of fractures and deformities. The double-rod application used at the femur decreases the number of revisions and prolongs the time of revision.

Rehabilitation of children with arthrogryposis

Arthrogryposis is a congenital, multiple and non-progressive deformation of the joints, which is characterized by a multiple contractures of the joints at the child's birth. Stiff joints are cylindrical in shape, retaining usual contours, with partially erased muscle and skin outlines. The classic form of arthrogryposis is usually referred to as amyoplasia in the current literature. The case presented here is of a female child aged 17, with the diagnosis of Arthrogryposis multiplex, categorized as mildly mentally disabled, semi-mobile and using wheelchair. The female subject is with deformities of both upper and lower extremities and is completely dependent on the help of another person in matters of usual daily activities, such as maintaining her personal hygiene and satisfying her basic living needs, also in practicing her basic skills. The rehabilitation plan is grounded upon the diagnosis of disease, as well as on the results based on a functional assessment. The rehabilitation plan included daily exercises, passive exercises for lengthening of the soft tissue structures, active sustained exercises, active exercises and those with load on all joints according to the estimation made by the manual muscle test. The plan was being implemented during the research over the course of one whole month. The patient cooperated greatly and was motivated to work. Treating children with arthrogryposis requires cooperation between physiatrists, surgeons, physiotherapists, occupational therapists, social workers, orthotics, with early and complete engagement of parents. Therefore, the treatment of arthrogryposis necessitates to be approached by all aforementioned experts as a team.

Clinical and Radiological Analysis of Angular Deformity of Lower Extremities

Clinical and Radiological Analysis of Angular Deformity of Lower Extremities

Treatment of pediatric patients with lower extremity deformities using software-assisted Ortho-SUV Frame: analysis of 213 cases

Aim. To retrospectively assess treatment outcomes of long bone deformities of the lower extremities accompanied by shortening in pediatric patients using a software-assisted Ortho-SUV Frame.Materials and methods. The accuracy of deformity correction (AC), period of deformity correction (PDC), external fixation index (EFI), and number of complications in 213 patients were retrospectively analyzed.Results. According to different parameters, AC of femur deformity correction (group 1) varied from 90% to 96%. The average length increase was 47 ± 12 mm. The average distraction duration was 38 ± 14 days. The average PDC was 8 ± 6 days for simple deformities (SDs), 14 ± 7 days for moderate deformities (MDs), and 23 ± 12 days for complex deformities (CDs). EFI was 26 ± 8 days/cm for SDs, 31 ± 6 days/cm for MDs, and 35 ± 12 days/cm for CDs. According to different parameters, AC of the lower leg deformity correction (group 2) varied from 89% to 95%. The average length increase was 52 ± 20 mm. The average distraction duration was 45 ± 18 days. PDC was 11 ± 5 days for SDs, 16 ± 9 days for MDs, and 27 ± 16 days for CDs. EFI was 32 ± 14 days/cm for SDs, 42 ± 12 days/cm for MDs, and 49 ± 8 days/cm for CDs. There were 48 (50.5%) complications in group I with the majority (71%) classified as Caton grade I and 29% as grade II. There were 62 (45%) complications in group 2, where 50% were Caton grade I and 50% were Caton grade II. There were no serious complications (Caton grade III) in either group that influenced the final functional results.Conclusion: Use of a software-assisted Ortho-SUV Frame increased the efficiency of treatment of pediatric patients with long bone deformities because of the great accuracy of deformity correction.

Limits of Growth Modulation Using Tension Band Plates in the Lower Extremities.

Growth modulation using tension band plates (TBP) has been shown to be a safe, effective, and popular method for correcting pediatric frontal plane angular deformity around the knee. Recently, TBPs have been used to achieve reversible epiphysiodesis to treat limb-length discrepancy. Many surgeons have expanded the indications to include diagnoses other than frontal plane angular deformities, anatomic sites other than the knee, and correction of sagittal and oblique plane deformities. Despite the rapid acceptance of TBPs, the limits of this option have not been explored. We undertook a systematic literature review and found that the success rate for idiopathic cases approaches 100% with a low complication rate. Pathologic cases have a slightly lower success rate and a higher complication rate. The potential to avoid osteotomy with growth modulation makes TBPs a reasonable option for all but the most extreme pediatric frontal and sagittal plane lower extremity deformities. Applications to hip deformities remain unproven.

The Tibial Slope in Patients With Achondroplasia: Its Characterization and Possible Role in Genu Recurvatum Development.

Genu recurvatum, a posterior resting position of the knee, is a common lower extremity deformity in patients with achondroplasia and has been thought to be secondary to ligamentous laxity. To the best of our knowledge, the role of the tibial slope has not been investigated, and no studies describe the tibial slope in patients with achondroplasia. Our goals were to characterize the tibial slope in children and adults with achondroplasia, explore its possible role in the development of genu recurvatum, and compare the tibial slope in patients with achondroplasia to that in the general population. We reviewed 252 lateral knee radiographs of 130 patients with achondroplasia seen at our clinic from November 2007 through September 2013. Patients were excluded if they had previous lower extremity surgery or radiographs with extreme rotation. We analyzed patient demographics and, on all radiographs, the tibial slope. We then compared the mean tibial slope to norms in the literature. Tibial slopes >90 degrees had an anterior tibial slope and received a positive prefix. Statistical analysis included intraclass and interclass reliability, Pearson correlation coefficient, and the Student t tests (significance, P<0.05). The overall mean tibial slope for the 252 knees was +1.32±7 degrees, which was significantly more anterior than the normal slopes reported in the literature for adults (7.2 to 10.7 degrees, P=0.0001) and children (10 to 11 degrees, P=0.0001). The Pearson correlation coefficient for mean tibial slope and age showed negative correlations of -0.4011 and -0.4335 for left and right knees, respectively. This anterior tibial slope produces proximal and posterior vector force components, which may shift the knee posteriorly in weightbearing. The mean tibial slope is significantly more anterior in patients with achondroplasia than in the general population; however, this difference diminishes as patients' age. An anterior tibial slope may predispose to a more posterior resting knee position, also known as genu recurvatum. Level IV-retrospective case series.

Lower Extremity Deformity Management in MPS IVA, Morquio-Brailsford Syndrome: Preliminary Report of Hemiepiphysiodesis Correction of Genu Valgum.

Morquio-Brailsford syndrome or mucopolysaccharidosis type IV-A (MPS IV-A) is an inherited metabolic disease in which skeletal deformities can be extreme. An international registry has shown that 46% of patients are unable to walk 200 m and 30% use a wheelchair. Lower limb surgery is performed to restore alignment with the expectation of maintaining mobility. We are, however, not aware of reports correlating function with alignment. This study assesses the role of orthopaedic intervention with reference to anatomic and functional outcome in MPS IV-A: specifically hemiepiphysiodesis correction of genu valgum. Interrogation of the MPS patient database identified 63 patients. Patient demographic and radiographic data were collected along with information on deformity, correction, mobility, and genotype. Genu valgum was assessed by intermalleolar distance and mobility by a standardized 6-minute walk test. Sequential hip anatomy was assessed radiographically. Twenty-six surgical hemiepiphysiodesis episodes were performed on 23 patients. There were no cases of implant failure, loosening, or infection. The average intermalleolar distance reduction was 6.12 cm (paired t test, P=0.0001) (95% confidence interval, 7.6-4.7 cm) and the mean change in 6-minute walk test was +69.5 m (P=0.0339). There was no correlation between hip subluxation/dislocation and mobility (Fisher exact test, P=1.000), although hip parameters deteriorated over time. Three patients required repeat 8-plate insertion and 1 a femoral osteotomy. Eight-plate hemiepiphysiodesis correction of genu valgum in MPS IV-A is an effective treatment with low complication rates. The insult of surgery is minimal compared with that of osteotomy which can reduce mobility further. Our outcomes suggest that mobility is maintained or improved even in severe genotypes where mobility typically worsens. We have found hip pathology to be less debilitating, but further studies are needed to assess the effect of genu valgum correction upon femoral head subluxation and collapse.We suggest hemiepiphysiodesis should be considered as part of the treatment strategy for limb alignment in MPS IV-A patients, depending on remaining growth, mobility status, and genotype. Level IV-therapeutic case series.

Effect of four monthly doses of a human monoclonal anti-FGF23 antibody (KRN23) on quality of life in X-linked hypophosphatemia

X-linked hypophosphatemia (XLH) is characterized by lower extremity deformities that lead to bone and/or joint pain that result from decreased renal tubular reabsorption leading to hypophosphatemia caused by elevated levels of fibroblast growth factor 23 (FGF23). ObjectiveValidate the use of SF-36v2 Health Survey (SF-36v2) and the Western Ontario and McMaster Osteoarthritis Index (WOMAC) to measure previously unstudied health-related quality of life (HRQoL) in XLH patients and determine the change in HRQoL before and after treatment with KRN23, a human monoclonal anti-FGF23 antibody. MethodsTwenty-eight adult outpatients with XLH received up to four doses of KRN23 administered subcutaneously every 28days. General HRQoL was measured with the SF-36v2 and condition-related HRQoL with the WOMAC at baseline and study endpoint as a secondary outcome of a Phase 1/2, open-label, multicenter, dose-escalation trial. ResultsTesting for scale discriminant validity and convergent-divergent validity supported the use of these scales in the assessment of HRQoL in XLH. Both instruments indicated impairment of physical function at baseline with all mean scores showing a trend to improved health at study endpoint compared to baseline. When corrected for multiple comparisons, the score for Role Limitations due to physical health on the SF-36v2 which measures the patient's perception of their own chronic functional impairments due to poor physical health remained significantly improved (P<0.05), increasing to the mean score of US adults. For the WOMAC, Physical Functioning and Stiffness scores were significantly improved (P<0.05). ConclusionKRN23 administration was associated with significantly improved patient perception of their Physical Functioning and Stiffness due to their disease. This study demonstrates that the SF-36v2 and WOMAC are valid tools for assessing HRQoL in XLH.

Effects of physical characteristics and residence style on alignment of lower extremity.

This research was performed to identify the incidence of deformity of lower extremity and to identify the relationship of the incidence between the deformities. Once the incidences and relationship are found, next purpose was to find the effects of physical characteristics and residence styles on the development of lower extremity deformities. One hundred fifteen males and 108 females participated in this study. Data collecting was performed by questionnaire and visual postural evaluation. The incidence of genu varus was significantly high in standing-up life style compared to sitting-on life style (chi-square=8.28; P=0.004). However, the incidences of heel varus (chi-square=13.223; P=0.004) and femoral torsion (chi-square=19.347; P<0.0001) were significantly high in sitting-on life style than standing-up life style. The incidences of genu varus (chi-square=24.18; P<0.0001), heel varus (chi-square= 15.412; P<0.0001), and tibial torsion (chi-square=6.285; P<0.012) were significantly high in sitting-on life style compared to standing-up life style (P<0.05). The odd ratio result for sitting-on life style against standing-up life style showed 6.6 times significantly high relationship in femoral torsion (95% confidence range, 1.64–26.47) in men.

Lengthening for functional acetabular dysplasia due to limb length discrepancy: A report of two cases

Osteoarthritis of the hip joint as a complication of limb length discrepancy (LLD) caused by lower extremity deformity is rarely reported in the literature. We report two such cases of osteoarthritic changes of the long leg hip joint due to severe LLD but no developmental dysplasia of the hip. Both underwent limb lengthening, and the symptoms were improved without further treatment. The osteoarthritic changes are secondary to functional acetabular dysplasia resulting in insufficient acetabular coverage of the femoral head and lateral inclination of the pelvis caused by LLD. Thus, lengthening treatment may be one option for such patients with osteoarthritis due to functional acetabular dysplasia.

Validation of a modified Scoliosis Research Society instrument for patients with limb deformity: The limb deformity-Scoliosis Research Society (LD-SRS) score

Background: Despite the large negative effect of limb deformity on health-related quality of life (QoL), there exists no patient-reported instrument to quantify this impact. Rather, limb deformity research has been performed using global QoL measurements concurrently with joint-specific and/or arthritis outcome scales, thereby requiring the completion of multiple instruments. Furthermore, joint- and arthritis-specific instruments focus on the impact pain has on function, whereas limb deformities may be pain-free with greater social and functional impairment. The purpose of this study was to validate a patient-reported instrument to quantify limb deformity-related QoL. Materials and Methods: Because of the similarities with regard to pain, function, and body image between limb deformity and scoliosis, the Scoliosis Research Society-30 (SRS-30) spine deformity instrument was modified such that the words back and trunk were replaced with limb to create a novel instrument: the limb deformity-SRS (LD-SRS). Testing for construct validity (both convergent and discriminant), reliability, floor and ceiling effects, and minimal clinically important difference (MCID) was performed in a validation cohort of 62 subjects aged 18 years or older with nonarthritic, unilateral lower extremity deformity. Results: Scale reliability was excellent (test-retest reliability, intraclass correlation coefficient = 0.977; internal consistency, Cronbach's alpha = 0.906), scores were normally distributed, and there were no floor or ceiling effects. There was also robust construct validity: convergent validity testing revealed positive correlations between the LD-SRS and all short-form-36 domains, the American Academy of Orthopaedic Surgeons-Lower Limb Module, and higher scores in those who were postcorrection. Discriminant validity was demonstrated with no correlations between the LD-SRS and subject age, sex, body mass index, surgeon-scored Limb Lengthening and Reconstruction Society-AIM Index, or surgeon-generated deformity measurements. MCID was calculated to be 0.3 (on a 4.0-point scale). Conclusions: The LD-SRS score is a reliable and valid instrument to measure limb deformity-related QoL in patients with nonarthritic lower extremity deformity. It is a valuable tool which allows clinicians to quantify patients' deformity-related QoL with a single instrument, rather than repurposing scales which have been validated for other conditions and have limited applicability to the unique challenges of treating patients with a lower limb deformity. Level of Evidence: Diagnostic, Level 2.

Normal values of foot arch parameters in adult Hausa population of Nigeria

Background: Deformities of foot arches have been implicated in various lower extremity injuries. Normal values of foot arch parameters have been studied in various populations. However, studies in Nigerian population are very limited and therefore require attention. Objective: The objectives of this study were to establish the normal values of foot arch parameters in adult Hausa population of Nigeria, to find the effect of gender on these parameters and to make comparison with previous studies in other populations. Materials and Methods: A total of 59 consented subjects (44 males, 15 females) that have no history of lower extremity deformity were recruited. Lateral radiograph of the right foot of each participant was taken in a bilateral standing position. For the medial longitudinal arch, navicular height (NH), first cuneiform height (FCH), calcaneal inclination angle (CIA), and calcaneal- first metatarsal angle (C1MA) were measured. Cuboid height (CH) and calcaneal-fifth metatarsal angle (C5MA) were measured for the lateral longitudinal arch. Measurements for angles and heights were performed using a universal plastic goniometer and a plastic ruler, respectively. Results: The mean (standard deviation [SD]) value of the NH was found to be 2.89 (0.54) cm, FCH 2.08 (0.44) cm, CIA 16.57° (3.30°), and C1MA 140.05° (5.63°). The mean (SD) of CH and C5MA was found to be 1.19 (0.31) cm and 160.96° (4.69°), respectively. There was no significant mean difference in those parameters between males and females. Conclusion: The mean values of foot arch parameters in adult Hausa population of Nigeria is comparable to previous studies on other populations, but generally lower than those of Caucasians. Similarly, our findings showed that gender has no significant effect on foot arch parameters.

Comparing three infant positions in paediatric life support

right proximal tibia was placed using a power driven device EZ-IO (Vidacare, San Antonio, TX, USA) and a15mm needle. The purpose of this study was to analyse the possible technical and anatomical factors leading into this complications. Material and methods: We measured the size of medullary diameter of the proximal tibia at the recommended site of IO access in 30 X-rays in three age groups: 1–28 days old full term neonates, 1–12 month old infants and 3–4 year old children. Children with syndromes or deformities in lower extremities were excluded. Results: The mean medullary diameter of the proximal tibia in neonates was 7.7mm, in infants 9.9mm and in 3–4 years old 12.4mm. The length of tip of the stylet and Y-shaped EZ-IOpaediatric needle, which had to be placed within the medullary cavity, is 4mm. Conclusion: The small size of intraosseous space especially in neonates and infants makes the correct placement of the IO needle and the avoidance of needle dislocation extremely challenging. In this patient group, the possibility of the rare complications: compartment syndrome and leg amputation should be taken into consideration.

Conventional Therapy in Adults With XLH Improves Dental Manifestations, But Not Enthesopathy.

X-Linked hypophosphatemia (XLH; OMIM no. 307800) is an X-linked dominant disease due to inactivating mutations in the PHEX gene that increase fibroblast growth factor 23 (FGF23) expression in bone, resulting in renal phosphate wasting and inappropriately normal calcitriol concentrations (1). Although there are currently no approved therapies for XLH, high-dose calcitriol and phosphate salts have been the mainstay of therapy for the past three decades (1, 2). There is general agreement that most affected children should be treated (if the administration and safety of therapy can be adequately monitored), but there is a lack of consensus regarding when to treat adults (1, 2). Features of XLH that frequently affect adults include short stature, lower extremity deformity (from rickets during childhood), bone pain, pseudofractures, osteoarthritis, stiffness from enthesopathy, and tooth abscesses. Obviously, treating adult patients will not correct lower extremity deformities or short stature, and except for patients with pseudofractures, XLH patients do not have increased fracture risk (3). However, some investigators have reported improvements in bone pain and osteomalacia in treated adults (4). In this issue of the JCEM, Connor et al (5) report retrospective observations made in 52 XLH patients regarding two important disease manifestations, enthesopathy and dental disease. Unfortunately, there are no large prospective trials on the effects of medical therapy on enthesopathy or dental disease. As for many other rare diseases, large, prospective, randomized, controlled trials are not feasible. The present study is the largest to date on the effect of therapy on these two disease manifestations, and it provides important information for the care of persons having XLH.

William John Little (1810-1894).

William John Little (1810-1894).

Updates in pediatric lower extremity deformity

During growth and development, a number of changes occur in the alignment of the child’s lower extremity. These dynamic changes, combined with the number of disease processes that can cause lower limb deformity can make evaluation and treatment challenging. In children with pathologic malalignment, a number of treatment options exist for correction, and over the last few years a number of innovative ideas have become more commonplace. This article discusses the normal development of childhood lower extremity alignment and reviews the current literature regarding treatment options for lower extremity deformities.

Opsismodysplasia: Phosphate Wasting Osteodystrophy Responds to Bisphosphonate Therapy

We present two siblings affected with opsismodysplasia (OPS), a rare skeletal dysplasia caused by mutations in the inositol polyphosphate phosphatase-like 1 gene. The skeletal findings include short stature with postnatal onset micromelia, marked platyspondyly, squared metacarpals, delayed skeletal ossification, metaphyseal cupping, and postnatal micromelia. Respiratory compromise, delayed ambulation, and progressive lower extremity deformities are described. The severity of findings is variable. Renal phosphate wasting is associated with severe bone demineralization and a more severe phenotype. This report represents the first described cases of opsismodysplasia treated with intravenous bisphosphonate (pamidronate). Surgical management for lower extremity deformities associated with OPS is also reviewed.Level of Evidence: IV Case series