Specific brace-fitting complications in idiopathic congenital talipes equinovarus (CTEV) have been rarely described in published series, and usually focus on non-compliance. Our primary aim was to compare the rate of persistent pressure sores in patients fitted with Markell boots and Mitchell boots. Our additional aims were to describe the frequency of other brace fitting complications and identify age trends in these complications. A retrospective analysis of medical files of 247 idiopathic CTEV patients born between 01/01/2010 - 01/01/2021 was performed. Data was collected using a REDCap database. Pressure sores of sufficient severity for clinician to recommend time out of brace occurred in 22.9% of Mitchell boot and 12.6% of Markell boot patients (X. 2. =6.9, p=0.009). The overall rate of bracing complications was 51.4%. 33.2% of parents admitted to bracing non-compliance and 31.2% of patients required re-casting during the bracing period for relapse. For patients with a minimum follow-up of age 6 years, 44.2% required tibialis anterior tendon transfer. Parents admitting to non-compliance were significantly more likely to have a child who required tibialis anterior tendon transfer (X. 2. =5.71, p=0.017). Overall rate of capsular release (posteromedial release or posterior release) was 2.0%. Neither medium nor longterm results of Ponseti treatment in the Australian and New Zealand clubfoot have been published. Globally, few publications describe specific bracing complications in clubfoot, despite this being a notable challenge for clinicians and families. Recurrent pressure sores is a persistent complication with the Mitchell boots for patients in our center. In our population of Australian clubfoot patients, tibialis anterior tendon transfer for relapse is common, consistent with the upper limit of tibialis anterior tendon transfer rates reported globally

Abstract. Congenital posteromedial bowing of tibia (CPMBT) progresses with decreasing deformity and increasing shortening. Lengthening in CPMBT has not been studied extensively. Our series compares duration and complications of lengthening in younger vs older children. Methods. 28 tibial lengthenings (23 patients) by a single surgeon, divided into two equal groups of 14 segments: group-A ≤ 5 years, Group-B > 5 years. Lengthening was done in all with external fixators. We measured preoperative (bo) and postoperative (po) deformities, initial limb length discrepancy (LLD), LLD at maturity (LLDm), % LLD, amount of lengthening (AmtL) and %L, external fixator duration (EFD) and external fixator index (EFI). We graded complications by Lascombes' criteria, results by ASAMI Bone score. Results. Mean age was 8.8 ± 7.1 years. Follow-up was 7.9 years. Group-A had significantly greater preoperative deformities. LLD was similar in both. Expected LLD at maturity (LLDM) using the multiplier method was greater than previously reported (group-A: 4.4 – 9.5 cm; group-B: 2.5 – 9.7 cm).%L was 24% in group-A and 15.7% in group-B (p=0.002). EFD and EFI were lesser in group-A than group-B. Lascombes' triple contract was fulfilled in 11/14 lengthenings in group-A vs. 3/14 in group-B. ASAMI bone score was good and excellent in both groups. Conclusions. In our large series of CPMBT lenghtenings, we found younger children presenting with large deformities and LLDm could be safely lengthened with lesser EFD and complications than older children

Introduction. Congenital posteromedial bowing of tibia (CPMBT) is characterized by a decreasing deformity and an increasing limb shortening. Our series compares the duration and complications of lengthening in younger vs older children. Materials and Methods. We studied 28 tibial lengthenings in 23 patients, divided into two equal groups of 14 segments: group-A ≤5 years (preschool) and Group-B >5 years. We measured preoperative (bo) and postoperative (po) sagittal, coronal, and oblique plane deformities, limb length discrepancy (LLD), amount of lengthening (AmtL), percentage lengthening (%L), external fixator duration (EFD) and external fixator index (EFI). Complications were graded by Lascombes’ criteria, results by ASAMI Bone score. Results. Mean age= 8.8 ± 7.1 years; mean follow-up= 7.9 years. Group-A had significantly greater bo-sagittal, coronal, and oblique plane deformities. LLD (3.4 cm in group-A vs. 4.1 cm in group-B) was similar in both. LLD at maturity (LLD. M. ) by multiplier method ranged 4.4–9.5 cm in group-A and 2.5–9.7 cm in group-B. Though AmtL (3.5 cm and 4.1 cm) was similar in both, %L was 24% in group-A and 15.7% in group-B (p=0.002). EFD (116.6 days) and EFI (33.7 days/cm) were lesser in group-A vs group-B (200.3 days, p=0.001; 50.2 days/cm, p=0.01). Lascombes’ criteria were fulfilled in 11/14 lengthenings in group-A vs. 3/14 in group-B. ASAMI bone score was good and excellent in both groups (p=0.44). Conclusions. Younger children with large deformities and LLD. M. could be safely lengthened with lesser external fixator duration and complications than in older children

Incidence of Congenital talipes equino varus [CTEV] is 1 to 2 per 1000 birth, Out of all cases 20% cases are Non-idiopathic. The management of non-idiopathic CTEV, however, continues to be challenging due to Rigidity, Poor skin condition, Bony changes, Vascularity and Associated congenital abnormalities. In recent literature, short term results of Ponseti method for correction of non-idiopathic CTEV have been encouraging. As Ponseti method decreases the severity of deformity and hence decreases the need for extensive surgery. The aim of current study is to evaluate the results of Ponseti method in Non-idiopathic CTEV. Total 7 children below the age of one year with Non idiopathic clubfoot presented to us in the duration of 2013 to 2015 who were treated by us. The cases included are Streeters Dysplasia with congenital constriction rings 3, Arthrogryposis multiplex congenita with Developmental dysplasia of hip 2, Arthrogryposis multiple congenita spina Bifida 1, Pierre Robinson Syndrome with Ichthiosis 1. Initially all the patients treated with Ponseti casting technique and scoring was done using modified pirani scoring. At an average we could correct the foot from Pirani 7 to 2.5 with a relapse in 4 patients. 2 patients were treated again by Ponseti's method with success while treatment was discontinued in 2 feet. We recommended Ponseti's technique in Syndromic clubfoot as an non-surgical initial modality with good results given. The final outcome may depend more on the underlying condition than the CTEV

Adult presentation of neglected congenital muscular torticollis is rare. We report 12 patients with this condition who underwent a modified Ferkel’s release comprising a bipolar release of sternocleidomastoid with Z-lengthening. They had a mean age of 24 years (17 to 31) and were followed up for a minimum of two years. Post-operatively a cervical collar was applied for three weeks with intermittent supervised active assisted exercises for six weeks. Outcome was assessed using a modified Lee score and a Cheng and Tang score. The mean pre-operative rotational deficit was 8.25° (0° to 15°) and mean lateral flexion deficit was 20.42° (15° to 30°), which improved after treatment to a mean of 1.67° (0° to 5°) and 7.0° (4° to 14°) after treatment, respectively. According to the modified Lee scoring system, six patients had excellent results, two had good results and four had fair results, and using the Cheng and Tang score, eight patients had excellent results and four had good results. Surgical management of adult patients with neglected congenital muscular torticollis using a modified Ferkel’s bipolar release gives excellent results. The range of neck movement and head tilt improved in all 12 patients and cosmesis improved in 11, despite the long-standing nature of the deformity

Purpose. Congenital insensitivity to pain is a rare autosomal recessive condition that leads to varying degrees of sensory and autonomic neuropathy. The aim of the study was to explore the common orthopaedic presentations of congenital insensitivity to pain and provide guidance on their treatment and complications. Methods. This study presents the results of fifteen patients with congenital insensitivity to pain, which were referred and treated at our supra-regional referral centre. Intradermal histamine tests and quantitative sweat tests were performed on all fifteen patients. Results. The average age of presentation was 13.2 years (range, two to 28 years). Eight patients presented with Charcot arthropathies and joint dislocations, which involved the foot/ankle (n=4), knee (n=2) or spine (n=2). Four patients presented with fractures or avascular necrosis affecting the tarsal bones and three patients presented with recurrent infections of the lower limbs. Patient education regarding appropriate shoe ware, pedal hygiene, periods of non-weight bearing, spinal bracing and close follow-up within the multi-disciplinary team was the mainstay of treatment. Patients with infection underwent cultures, aspiration, magnetic resonance imaging and treatment with antibiotics. Only one patient required joint washout for septic arthritis of the ankle. Conclusions. Congenital insensitivity to pain presents with both acute and chronic pathology affecting the weight-bearing joints. Treatment should be aimed at off-loading the pressure on these joints and preventing the development of further complications. Surgical intervention should be reserved for patients not responding to conservative treatment or those requiring debridement/washout for extensive infection

Purpose of study:. Congenital hallux varus is a rare condition presenting with medial deviation of the big toe. It consists of 2 variants: classical congenital hallux varus caused by an abnormal metatarsal-phalangeal articulation, and a more recently described variant due to a “bracket physis” of the first metatarsal. Our aim was to perform an audit of the spectrum of presentation of congenital hallux varus with its management and complications in our unit over a five year period. Description of methods:. A retrospective review of congenital hallux varus treated by a single surgeon was performed. Clinical notes, photographs and x-rays were reviewed. Two surgical methods of treatment were used as directed by clinical and radiological findings. Summary of results:. Four patients with congenital hallux varus were identified. Three had bilateral involvement, i.e. seven feet were treated. The ages of the patients ranged from 1 to 9 years, with 2 boys and 2 girls receiving treatment. In two patients (4 feet) the deformity was associated with pre-axial polydactyly. One patient had associated hand deformities. Only one of our four patients had a “bracket physis” and was treated with a metatarsal osteotomy. The other three patients (6 feet) were treated by soft tissue realignment using the Farmer procedure. One patient who had bilateral Farmer procedures subsequently developed a bunion over the 1st metatarso-phalangeal joint of one foot due to uncovering of the metatarsal head. No complications or recurrences were recorded in the other three patients on follow up visits. Conclusion:. Careful clinical and X-ray analysis is important to determine the type of congenital hallux varus and which method of surgical treatment is appropriate. Long term follow up is required to identify subsequent deformities

Complex congenital foot deformities pose a challenge to the surgeon due to poor results after extensive surgery. We report the clinical outcomes of children with complex congenital foot deformities treated with UMEX® (Universal mini-external fixator System) frames. This is a prospective review of our experience in patients treated in this way, from 2004 to 2011. The indications for treatment included resistant/recurrent Congenital Talipes Equino Varus (CTEV), cavo-varus deformity secondary to Charcot-Marie-Tooth disease, arthrogryposis, fibular hemimelia and other congenital abnormalities. A total of 32 children (35 feet) have been treated, out of which 22 were male and 10 were female patients. Age at surgery ranged from 3 to 15 years (median age – 7 years). Three patients underwent bilateral procedures; the reminder (29 patients) underwent unilateral foot operations. Twenty-eight patients had undergone previous surgery including soft-tissue and/or bony corrective procedures. The frames were removed at an average of 69 days after application, and the patients spent a further 6 weeks in a walking cast. Good functional outcomes were noted in 26 patients in the first postoperative year and in 19 patients in the fifth postoperative year. Further operations were needed in 10 patients. Complications occurred in 10 patients, predominantly pin-site infections and 1 case of bony overgrowth at pin-site and 1 of proximal tibio-fibular diastasis. This is a simple fixator to use with a short learning curve. In groups of patients with complex congenital abnormalities, we achieved good functional outcome with low-complication rates

Untill recently, major reduction defects of the tibia were treated by amputation and prosthetic fitting. However, Wada et al (1) and Weber (2) recently reported impressive results of limb reconstruction in children with tibial aplasia. If an attempt is being made to reconstruct the leg and foot, a clear understanding of the nature of anomalies is necessary. A retrospective study of case records and radiographs of children with congenital anomalies of the tibia seen at our centre was undertaken to determine the patterns of associated anomalies in the leg and foot. In addition, five amputated specimens of the leg and foot from children with complete tibial aplasia were dissected. A wide spectrum of congenital anomalies of the tibia was seen and this included complete aplasia, partial aplasia, hypoplasia, dyplastic trapezoidal tibia and congenital bowing. Complete and partial aplasia was seen either with or without duplication of the formed skeletal elements. The patterns of duplication that were seen included fibular dimelia, pre-axial mirror polydactyly, duplication of the calcaneum, cuboid and lateral cuneiforms. Trapezoidal dysplastic tibia was associated with duplication of the talus and pre-axial mirror polydactyly. Dissection of the amputated specimens of complete tibial aplasia revealed aplasia of some muscles, aberratant tendinous structures, abnormal insertion of muscles and absence of the plantar arterial arch. An understanding the nature of these associated anomalies in children with tibial aplasia and dyplasia will help the surgeon to decide the strategies for reconstruction of the limb if that is the desired option. At the other end of the spectrum of congenital anomalies of the tibia is posteromedial bowing which was considered an innocuous condition that required little or no treatment. A review of 20 cases of posteromedial bowing demonstrated that there are number of problems related to the leg, ankle and foot that may require surgical intervention

We present a retrospective review of a single-surgeon series of 30 consecutive lengthenings in 27 patients with congenital short femur using the Ilizarov technique performed between 1994 and 2005. The mean increase in length was 5.8 cm/18.65% (3.3 to 10.4, 9.7% to 48.8%), with a mean time in the frame of 223 days (75 to 363). By changing from a distal to a proximal osteotomy for lengthening, the mean range of knee movement was significantly increased from 98.1° to 124.2° (p = 0.041) and there was a trend towards a reduced requirement for quadricepsplasty, although this was not statistically significant (p = 0.07). The overall incidence of regenerate deformation or fracture requiring open reduction and internal fixation was similar in the distal and proximal osteotomy groups (56.7% and 53.8%, respectively). However, in the proximal osteotomy group, pre-placement of a Rush nail reduced this rate from 100% without a nail to 0% with a nail (p < 0.001). When comparing a distal osteotomy with a proximal one over a Rush nail for lengthening, there was a significant decrease in fracture rate from 58.8% to 0% (p = 0.043). We recommend that in this group of patients lengthening of the femur with an Ilizarov construct be carried out through a proximal osteotomy over a Rush nail. Lengthening should also be limited to a maximum of 6 cm during one treatment, or 20% of the original length of the femur, in order to reduce the risk of complications

We report the clinical outcomes of children with complex congenital foot deformities treated with UMEX® mini-external fixators. This is a prospective review of our experience in patients treated in this way, from 2004. The indications for treatment were resistant/recurrent Congenital Talus Equina Varus(CTEV), cavo-varus deformity secondary to Charcot-Marie-Tooth disease, arthrogryposis, fibular hemimelia and other congenital abnormalities. In addition, one patient underwent this treatment since he was allergic to casting material. A total of 32 children (35 feet) have been treated, with a male to female ratio of 22:10 respectively. The patient-age at operation ranged between 3 and 15 years (median age −7 years). Three patients underwent bilateral procedures and 29 patients underwent unilateral foot operations. Twenty-eight patients underwent previous soft-tissue and bony corrective operations with serial casting. The frames were removed at an average of 69 days after application with a further 6 weeks in a walking cast. Seventy-nine percent of the patients had good functional outcome. Further operations were needed in 10 patients. Complications occurred in 10 patients, including pin-site infections, bony overgrowth at pin-site and proximal tibio-fibular diastasis. In conclusion, this is a simple fixator to use with a small learning curve. In groups of patients with complex congenital abnormalities, we achieved good functional outcome with low-complication rates

Malformation and hypoplasia of the clavicle can result in pain, impaired function, restricted shoulder movement, subjective feeling of instability and cosmetic deformity. There are no reports of clavicle lengthening by osteotomy and distraction osteogenesis (DO). This is a retrospective review of 5 patients (7 clavicles) who underwent clavicle lengthening by DO using a monolateral external fixator for clavicular hypoplasia. There were 3 males and 2 females with mean age 15 years (9 to 23) and mean follow-up 21 months (8 to 51). Preoperative diagnoses included Klippel-Feil syndrome, cleidocranial dysplasia with torticollis, congenital myopathy and Noonans syndrome and obstetric brachial plexus injury. Mean length gained was 31 mm (15 to 41) which represens an average of 24.7% of overall bone length. Mean time in fixator was 174 days (161 to 263) and mean external fixation index was 56 days/cm. Two patients required internal fixation following fixator removal to consolidate union and one required additional internal fixation for atrophic regenerate. Mean preoperative oxford shoulder score improved from 28.5 to 41 and all patients were extremely satisfied with their result. Two patients developed pin site infections. Clavicular lengthening by distraction osteogenesis for congenital clavicular hypoplasia is a previously unreported technique that enables gradual correction of deformity without risking brachial plexus traction injury following acute correction. It has the potential to improve shoulder pain, function, range of movement and cosmesis. Distraction ≥25% of overall bone length may require additional plate fixation to consolidate union

This is the first study in the Ponseti-era to compare severity and outcomes in cases of idiopathic congenital talipes equinovarus (CTEV) diagnosed antenatally versus those diagnosed at birth. Small pre-Ponseti studies showed antenatal diagnosis to be a predictor of severity and poor prognosis. Prospective data collection was used to compare indicators of severity and outcomes for idiopathic CTEV between these two groups. These include Pirani score, number of casts, follow-up Roye score and need for surgery. 68 children with 106 affected feet were included. Antenatal diagnosis (AD) was made in 45 children (71 feet), with birth diagnosis (BD) in 23 children (35 feet). Mean follow-up age was 4.8 years (AD = 4.9, BD = 4.7), male:female ratio 2:1 (AD=BD) with bilateral CTEV in 55% (AD = 58%, BD=52%). Mean initial Pirani scores were 5.25 in the AD group vs 4.86 in the BD group (p=0.06). Mean Roye score at follow-up was 1.39/4 in the AD group vs 1.26/4 in the BD group (p=0.33) with 33% vs 30% complaining of pain respectively (p=0.80). Surgery was needed in 11/71 (15.5%) in the AD group vs 1/35 (2.9%) in the BD group (p=0.06)). There is no significant difference in severity between antenatal and birth diagnoses of idiopathic CTEV and no difference in outcomes between these groups when treated with the Ponseti regime. Although small, our sample size is greater than the largest published comparable study

Congenital Talipes Equinovarus (CTEV) occurs in approximately 1 in 1000 live births. Most cases occur as an isolated birth defect and are considered idiopathic. The widespread adoption of the Ponseti technique of serial casting followed by Achilles tenotomy and long term bracing has revolutionised the outcomes in CTEV. In most cases, plantigrade, flexible, pain-free feet may be produced without the need for extensive surgery. It is estimated that about 10% of cases of CTEV are not idiopathic. These feet are stiffer and more challenging to treat. In particular, there is little evidence in the literature concerning the efficacy of the Ponseti method in these cases. In our institution, a dedicated weekly Ponseti clinic has operated since 2005. To date 140 patients have been treated. We prospectively enter all details regarding their management onto an independent international database. The aim of this study was to audit the non-idiopathic cases of CTEV and to assess the effectiveness of the Ponseti technique in these challenging cases. Outcome measures included the Pirani score and eventual need for surgical intervention. We identified 29 cases (46 feet) with non-idiopathic CTEV. This comprises 21% of our workload. Seventeen were bilateral. The commonest diagnoses were neuromuscular conditions such as spina bifida (5 cases) and cerebral palsy (3 cases). There were 4 cases of Trisomy 21. Other causes included Nail Patella syndrome, Moebius syndrome, Larsen syndrome and Ito syndrome. In approximately 12% of cases, the underlying disorder remained undiagnosed despite thorough medical and genetic testing. In cases of non-idiopathic CTEV, the mean starting Pirani score was 5.5 (out of 6). After serial casting and Achilles tenotomy, the average score was 2.0. Twenty-one of 46 feet (46%) ultimately required further surgical intervention (mostly posteromedial release). We found that certain conditions were more likely to be successfully treated with the Ponseti method – these included conditions characterised by ligamentous laxity such as Trisomy 21 and Ehlers Danlos syndrome. All patients showed some improvement in Pirani score after serial casting. We believe that it is essential to attempt the Ponseti method of serial casting in all cases of CTEV. More than half of all non-idiopathic cases will not require further surgical intervention – and those that do are not as stiff thanks to the effects of serial casting. Thus, the surgery required is not as complex as it might otherwise have been. This is the largest series of its kind in the current medical literature

Congenital talipes equinovarus occurs in 1.2 per 1000 live births in Europe and is twice as common in boys. Over the last decade, non-surgical management has re-established itself as the first line treatment; after long-term follow-up of surgically treated patients, revealed high rates of over correction, stiffness and pain. The commonly practiced non-surgical approaches are the Ponseti technique of serial manipulation and casting, and French taping. Ram's technique of taping is a truly conservative approach with a higher success rate to address this problem. Unlike French taping, it involves taping alternate days during the first week followed by twice in the second week, then once the following week, which is left in situ for a further two weeks. After the initial five weeks of taping, patients are provided with talipes splint for all time use, up till a year. This is followed by talipes shoes for walking and splint for nighttime use for another year. At the end of two years patients can wear normal shoes. The study includes 225 patients with 385 clubfeet, who were treated with Ram's taping technique from September 1991 to August 2008. Inclusion criteria were age up to three months and previously untreated clubfeet. Average follow up was of 5.6 years. Outcome ratings at a minimum of two years were performed. Initial correction rate at the end of five weeks was 99%. A relapse of 21% was noted, two-third of which was salvaged via further taping and exercise, while remaining one third needed some form of surgical intervention. The comparative outcome for Ram's taping is better to Ponseti or French taping with good outcome in 93%, in comparison to 72% and 67% respectively. To conclude Ram's taping is a fast, more effective, less cumbersome and fully conservative approach of correcting the clubfoot deformity

Introduction

This is a report of the outcome of management of congenital pseudoarthrosis of the tibia (CPT) at skeletal maturity.

This study is a mid-term follow up of an original series of 51 babies treated with a modified Ponseti technique for idiopathic congenital talipes equinovarus using below-knee Softcast (easier to remove and hygienic). 1. to determine whether this method is as effective as traditional above-knee plastering. Methods. 51 consecutive babies were treated (April 2003-May 2007) and serial Pirani scores were recorded. Dennis Browne Boots (DBB) were applied when correction was achieved and an Achilles tenotomy was performed if necessary to complete the correction. DBB were worn fulltime for 3 months and at night for 3.5 years. Results. Of the original 51, 3 were lost to follow up and 3 were diagnosed with a neuromuscular condition and excluded. 45 patients, 34 boys and 11 girls were followed up for a mean of 55.3 months (range 36–85 months). Mean age at presentation was 16 days with a median Pirani score of 6.0 (5.5, 60). 75.7% required an Achilles tenotomy before DBB. Median Pirani score at tenotomy was 2.5 (2.0, 2.5). Time to boots (weeks) was mean 5.0 (4.2, 6.0) in the non-tenotomy group and 10.7 (9.8, 11.8) in the tenotomy group. 2 patients had residual deformity after plastering requiring surgery and there were 6 recurrences requiring surgery (4 tibialis anterior tendon transfers and 2 open releases). There appears to be a greater risk of operative intervention for girls and non-compliance with DBB. The estimate of 5-year (60 month) survival without surgery was 85% (96% CI; 70,99%). Conclusion. Below knee Softcast allows correction of CTEV with comparable results to traditional above knee techniques. Consistent with current literature, our series found that compliance with DBB is one of the strongest predictors of success. Brewster MB, Gupta M, Pattison GT, Dunn-van der Ploeg ID. Ponseti casting: a new soft option. JBJS(Br) 2008 Nov; 90(11): 1512–1515

CPT is a uniquely difficult condition, often associated with Neurofibromatosis (NF1), where bone healing is compromised. Although rare, the severity of this condition and the multiple procedures often entailed in treating it, warrant research attention. As study material is limited, animal models of the disorder are desirable for testing new treatments.

We sought to create a model of CPT where both copies of the NF1 gene were ablated at the fracture site, as has been found in some clinical specimens. NF1 floxed mice had fracture surgery; both closed fracture and open osteotomy were performed. Either a Cre- or control GFP-adenovirus was injected into the fracture site at day zero. Recombination was confirmed in ZAP reporter mice. Additionally, cell culture studies were used to examine the possible responses of NF1+/+ (wild type) NF1+/− or NF1−/− to drugs which may rescue the dysregulated Ras/MAPK pathway in NF1.

In closed fractures, radiographic bridging was 100% in NF1+/+ calluses and <40% in NF1−/− calluses (P<0.05). In open fractures, radiographic bridging was 75% in NF1+/+ calluses and <30% in NF1−/− calluses (P<0.05). In both fracture repair models the NF1−/− state was associated with a significant up to 15-fold increase in fibrotic tissue invading the callus by week 3. In NF1−/− fractures, large numbers of TRAP+ cells were observed histologically in the fibrotic tissue. Closed fractures also showed a significant increase in BRDU labelled proliferating cells in the callus. In cell culture models of NF1 deficient osteogenesis, NF1−/− progenitors were found to be significantly impaired in their capacity to form a calcified matrix as measured by Alizarin Red S staining and osteogenic markers (Runx2, Osteocalcin, Alp expression). However, when differentiated calvarial NF1 floxed osteoblasts were treated with Cre adenovirus, mineralization was not affected, suggesting that NF1 impacts on osteogenic differentiation rather than mature cell function. Treatment with MEK inhibitor PD0325901 was found to rescue the NF1−/− progenitor differentiation phenotype and permit robust mineralization. Treatment with the JNK inhibitor SP600125 was also able to improve ALP activity and mineralization in NF1+/− osteoprogenitors compared to control cells.

This model of NF1 −/− induction at a fracture or osteotomy site closely replicates the clinical condition of CPT, with lack of bone healing and fibrous tissue invasion. Underlying defects in bone cell differentiation in NF1 deficiencies can be at least partially rescued by JNK and MEK inhibitors.

Presenters Position:

Aim

To determine the preferable treatment for congenital pseudarthrosis of the tibia, we retrospectively reviewed 19 patients (20 limbs) treated consecutively over a 22 year period (1988–2007). Fifteen were followed up to maturity. The patients were assessed for union, leg length discrepancy (LLD), ankle valgus, range of ankle movement and distal tibial physeal injury.