Complex, atypical clubfoot: follow-up after up to 16 years reveals a high risk of relapse but good functional and radiological outcomes.

INTRODUCTION: The treatment of complex atypical clubfoot poses many challenges. In this paper, we report on the course of complex clubfoot, primary correction using the modified Ponseti method and midterm outcomes. Special consideration is given to clinical and radiological changes in cases of relapse. MATERIALS AND METHODS: Twenty-seven cases of complex, atypical, non-syndromic clubfoot were treated in 16 children between 2004 and 2012. Patient data, treatment data, functional outcomes and, in the relapse cohort, radiological findings were documented during the course of treatment. The radiological findings were correlated with the functional outcomes. RESULTS: All atypical complex clubfeet could be corrected using a modified form of the Ponseti method. Over an average study period of 11.6 years, 66.6% (n = 18) of clubfeet relapsed. Correction after relapse showed an average dorsiflexion of 11.3° during a 5-years' follow-up period. Radiological results showed residual clubfoot pathologies such as a medialized navicular bone in four clubfeet. There were no instances of subluxation or dislocation of the talonavicular joint. Extensive release surgery was not necessary. Nevertheless, after 2.5 preoperative casts (1-5 casts), bone correction was performed in n = 3 feet in addition to Achilles tendon lengthening and tibialis anterior tendon transfer. CONCLUSION: Good primary correction of complex clubfoot using the modified Ponseti technique results in a high recurrence rate in the medium term. Relapse treatment without peritalar arthrolysis procedures produces good functional results even though minor residual radiological pathologies did persist in a minor number of cases.

[Hip dysplasia-new and proven methods]. / Hüftdysplasie ­ Neues und Bewährtes.

BACKGROUND: Hip dysplasia is one of the most common disorders in paediatric orthopedics. With the development of ultrasound techniques treatment has changed, and earlier diagnosis and treatment is possible. So, for more than 20 years diagnosis and treatment has been focused on ultrasound. Many papers reporting new diagnostic techniques like MRI have been published. Arthroscopic reduction is a new surgical procedure. However, established surgical procedures continue to play an important role in the treatment. CURRENT TREATMENT: This paper presents new and established diagnostic techniques, conservative and surgical treatment options. Unfortunately, due to the great number of publications, not all aspects could be taken into account. In particular, we describe the diagnostic and treatment standards in German-speaking countries based on ultrasound hip screening. However, also international aspects of diagnostic and treatment options have been included.

Limitation of flatfoot surgery in overcorrected clubfeet after extensive surgery.

INTRODUCTION: Flatfoot is a severe complication of extensive clubfoot surgery. In this retrospective study, we evaluated our results following flatfoot surgery in overcorrected clubfeet. The aim was to analyze the success of different surgical techniques, including tarsal osteotomies and arthrodesis, in correcting different types of flatfeet. MATERIAL AND METHOD: Between January 1, 2011 and December 31, 2015 we treated 25 severe cases of flatfeet after extensive clubfoot surgery. We classified the hindfoot deformities into rotational valgus, hinge valgus or translatory valgus based on AP standing X-rays. Tarsal osteotomies (Mitchell, Evans, Cotton) and arthrodesis were adapted based on age and severity. Age, gender, pain, hindfoot valgus and function were documented. Function and X-rays were compared pre- and postoperatively. RESULTS: There were 17 male and 4 female patients. Age at operation ranged from 11 to 26 years with an average age of 14.3 years. The mean follow-up was 27.6 months (7-60 months). Primary surgical treatment was a tarsal osteotomy in 19 cases and in six cases it was arthrodesis. Hindfoot valgus (Ø 18.6°-3.2°), calcaneal pitch (Ø 6.2°-14.6°), Costa Bartani angle (Ø155°-142°) and Meary angle (Ø 2.0°-8.8°) improved pre- to postoperatively. Range of motion did not improve after surgical correction. 81% were satisfied with the postoperative results. All flatfeet with translatory valgus, initially treated with a tarsal osteotomy, needed further arthrodesis due to primary undercorrection. CONCLUSION: Tarsal osteotomies are successful methods for correcting flatfeet following extensive clubfoot surgery with rotational valgus and mild hinge valgus. Tarsal osteotomies are unable to successfully correct flatfeet that have a translatory valgus. In such cases, we recommend double or triple arthrodesis. The functional outcome is limited by the preop range of motion and the appearance of talus deformities.

Surgical dislocation for pediatric and adolescent hip deformity: clinical and radiographical results at 3 years follow-up.

INTRODUCTION: The aim of this study is to evaluate the clinical, radiographic short-term results and complications after surgical hip dislocation in young patients (≤18 years). MATERIALS AND METHODS: Clinical and radiographic outcomes were assessed in patients who underwent a surgical hip dislocation Ganz-type approach between 2008 and 2012. Diagnosis included Legg-Calvé-Perthes disease, slipped capital femoral epiphysis, femoroacetabular impingement, osteonecrosis of the femoral head, multiple hereditary exostoses and pigmented villonodular synovitis. Clinical data, the modified Harris hip score, nonarthritic hip score, 12-item short form health survey, the Stulberg classification, morphometric indexes, signs of osteonecrosis and osteoarthrosis were used for the evaluation. RESULTS: After a mean 3 years follow-up (range 0.5-6 years), 53 hips (51 patients) were evaluated. The most common diagnoses were Legg-Calvé-Perthes disease, slipped capital femoral epiphysis, femoroacetabular impingement and multiple hereditary exostoses. Mean age at surgery was 14 years (range 10-18 years). Through this approach femoral head-neck osteoplasty, Dunn-type osteotomy, labrum refixation, synovectomy, femoral head mosaicplasty open reduction and fixation for slipped capital femoral epiphysis were performed, finally in association with pelvic or intertrochanteric osteotomy. At follow-up, better outcome scores were obtained, progression of the osteonecrosis of the femoral head was observed in four cases and three further patients required the implant of a total hip prosthesis. CONCLUSIONS: After 3 years follow-up, results are comparable to previous studies and patients have a high rate of satisfaction, however the effectiveness of those procedures have to be proved on the long term. Results and complications seem to be related with preoperative lesion(s) and type of treatment. LEVEL OF EVIDENCE: Level IV, retrospective study, case series.

Solitary bone cyst: a comparison of treatment options with special reference to their long-term outcome.

BACKGROUND: Solitary bone cysts (SBC) are benign, tumor-like lesions, which most frequently occur in the proximal metaphyseal-diaphyseal region of the humerus and femur of children and adolescents. The lack of a clear pathoetiology has impeded the development of treatment strategies. Up to date there is no consensus or official guideline for when and how treat SBC. The purpose of this study was to evaluate the effectiveness and the longterm clinical outcome of the treatment of SBC. Different techniques have been used dependant of the site of lesion, dimension, medical history and activity status. METHODS: 135 skeletal immature patients with a solitary bone cyst were included. A follow up of 36 months or more was available for all patients. 22 patients were treated conservatively. All the other patients had at least one surgical intervention. The following four surgical treatment modalities were used: injection of methylprednisolon acetat (steroids), intramedullary nailing (IN), IN + steroids and curettage plus bone grafting. RESULTS: There was no significant difference between the treatment groups with respect to secondary fractures, function, pain, or complications. In the individual groups the failure rate after initial treatment was 36,6% with steroids, 50% with intramedullary nailing, 21,4% with intramedullary nailing plus steroids and none in the remaining group. CONCLUSION: Steroid injection remains a reliable method for treating solitary bone cysts owing to its low invasiveness. To prevent fractures and allow a full weight bearing, internal fixation in combination with methylprednisolon acetat injections seems to be the most favorable in weight bearing bones.

Arthroscopic Anatomy of the Dislocated Hip in Infants and Obstacles Preventing Reduction.

PURPOSE: The purpose of this study was to describe the anatomy as seen arthroscopically, the role of the labrum and its relevance in luxation and reduction procedures, and secondary changes to the cartilaginous acetabular roof and to determine the main obstacles preventing reduction of dislocated hips in infants and young children. METHODS: A specialized pediatric medial approach to hip arthroscopy was performed on 25 hip joints in 21 patients younger than 4 years of age. The arthroscopic procedure was conducted using a 2.7-mm cannulated instrument. A subadductor portal was used for the 70° arthroscope, and a high anterolateral portal served as a working portal. The anatomic findings of the individual hip joints were recorded. We examined the femoral head, the teres ligament, the transverse ligament, the acetabulum, and the acetabular labrum. The obstacles preventing reduction were successively resected. RESULTS: An arthroscopic investigation of all major structures and arthroscopic reduction was possible in 25 hip joints. A hypertrophic teres ligament was present in 23 of the 25 hips. Capsular constriction prevented reduction in 22 of the 25 hips. The acetabular labrum was not inverted in any of the examined hip joints and was also never an obstacle to reduction. Secondary changes to the cartilaginous preformed acetabular roof were present in 10 hips. CONCLUSIONS: We have shown that arthroscopy of a developmentally dislocated hip can be safely performed using the subadductor portal. Through this arthroscopic approach, we were able to identify the previously described pathologic structures-the limbus, neolimbus, pulvinar, hypertrophic teres ligament, and capsular constriction. The capsule was the most common block to reduction, followed by the teres ligament. Successful reduction can be achieved by removal of intra-articular tissues, the pulvinar, and the teres ligament, and nearly always a capsular release. The limbus and neolimbus were not factors in achieving reduction in our series. LEVEL OF EVIDENCE: Level IV, case series.

Arthroscopic reduction and acetabuloplasty for the treatment of dislocated hips in children of walking age: a preliminary report.

INTRODUCTION: This paper presents our initial findings on the use of arthroscopic hip reduction in conjunction with acetabuloplasty to treat patients of walking age who had congenital dislocation of the hip. MATERIALS AND METHODS: Arthroscopic reduction with acetabuloplasty was performed on nine children of walking age with nine dislocated hips. The average age of the patients was 21.4 months (14-41 months). Arthroscopic reduction was performed using a two-portal method with a 2.7-mm mini cannulated arthroscopic instrument. We used a subadductor portal and a high anterolateral portal. The obstacles preventing reduction-hypertrophic teres ligament, pulvinar, capsular constriction, hypertrophic transverse ligament-were eliminated. RESULTS: We treated one grade 4 hip, four grade 3 hips and four grade 2 hips, as classified by Tönnis. We were able to perform arthroscopic reduction on all of the hips. The main obstacles preventing reduction were a capsular constriction and a hypertrophic teres ligament. During the investigation period, which averaged 15.4 months (6-29 months), no repeat dislocation occurred. According to the Tönnis classification system for avascular necrosis, there were two cases of a grade 2 necrosis of the femoral head. The average preoperative AC angle was 40° (34°-47°). The average AC angle at the follow-up examination was 18.7° (11°-27°). CONCLUSIONS: We can conclude that the standardized arthroscopic surgical technique presented here can also be used to safely perform arthroscopic reduction in toddlers. The new arthroscopic method is an alternative to open reduction for selective hip dislocations. We believe this approach can be used to treat dislocated hips that are classified as grades 2 and 3 dislocations according Tönnis. Early results are promising. Medium-term results are needed to make a definitive statement on the rates of necrosis of the femoral head.

[Stress injuries of bone in children and adolescents]. / Stressverletzungen des Knochens bei Kindern und Jugendlichen.

Stress injuries of bone in childhood and adolescence are the result of an imbalance between physical stress on the growing musculoskeletal system and its intrinsic resilience. Children who are very active in sports are particularly affected. The classical stress injuries mainly occur in the area of the lower leg, the metatarsus and the lower lumbar spine due to the disproportionate load on healthy bone; however, overuse syndromes can also occur in the area of the growth plates and possibly lead to growth plate disorders. The anamnesis usually shows stress-related pain that has existed for a long time without trauma. As part of the differential diagnosis, a stress injury must first be included in the considerations due to it being a rare entity. An X­ray examination can show the first signs of a stress reaction. In the event of a conspicuous periosteal reaction, a malignant event must also be considered. As a rule, the MRI examination is then groundbreaking and in some rare cases biopsies have to be considered. The treatment of stress injuries is usually conservative. Recurrences should be counteracted by exercise control.

Fractures of the Humeral Ulnar Condyle in Children - a Rare but Complicated Injury. / Die Condylus-ulnaris-humeri-Fraktur des Kindes ­ eine seltene, aber komplikationsträchtige Verletzung.

BACKGROUND: Ulnar humeral condyle fractures are rare paediatric elbow fractures, classified as Salter-Harris IV paediatric elbow injuries. Due to constant radiological changes in the elbow with varying manifestation of ossification centres as well as late ossification of the trochlea, diagnosis of these injuries is challenging. To avoid long-term complications, the treating surgeon should be familiar with the rare injury picture, diagnostics and adequate therapeutic measures. MATERIAL AND METHODS: The present retrospective study includes data on all paediatric cases from 2002 to 2019 with primary or secondary treatment at a paediatric traumatology centre for ulnar condyle fracture with a minimum follow-up of 12 months. Range of motion, joint stability under valgus and varus stress as well as axial ratios of the injured and uninjured side were evaluated in a clinical follow-up examination. The Mayo Elbow Performance Score was used to objectify functional results. RESULTS: 20 children, average age 8.6 years (4 - 13) and average follow-up time 25 months, were included. Radiological evaluation based on Jakob and Fowles classification revealed a type I fracture in three cases, a type II fracture in one case and a type III fracture in 16 cases. Three cases were treated nonoperatively with an upper arm cast. 17 children were treated with open reduction and internal fixation. Diagnosis of three fractures was delayed. No postoperative complications such as infections, nerve damage or nonunions. 15 children showed free elbow function. Three children showed slightly restricted elbow extension by less than 10° and two by 10°-20°. All children showed free pro/supination. 18 children showed a physiological and bilaterally identical arm axis compared to the uninjured side. Two children showed a slightly increased cubitus valgus with a 5 - 10° difference between sides. Radiologically, two children with delayed fracture treatment showed partial necrosis of the trochlea. The Mayo Elbow Score showed good (2) to excellent results in all children (18). CONCLUSION: Very good clinical and functional results can be expected if the injury is diagnosed without delay followed by adequate therapy. Misdiagnosis of ulnar condyle fractures can be associated with the development of nonunions and functional restrictions as well as, after operative therapy, trochlear necrosis. Children up to the age of 6 in particular are at risk of misdiagnosis due to faulty assessment of the cartilaginous trochlea.

A CT-free protocol to treat osteoid osteoma of the hip region in childhood and adolescence by percutaneous drilling and by hip arthroscopy.

INTRODUCTION: It is often difficult to clinically and radiologically diagnose intra-articular osteoid osteomas and osteoid osteomas of the hip joint. Treatment can also be difficult due to complex locational relationships. CT-guided radiofrequency ablation is currently the standard form of treatment.In this paper we report on a minimally-invasive concept for treating osteoid osteomas near the hip joint in children and adolescents which does not involve using computed tomography. MATERIAL AND METHOD: 10 patients with an average age of 12.1 years underwent treatment for osteoid osteomas in the hip joint region. The diagnosis was made using a contrast-enhanced MRI. The osteoid osteomas were marked percutaneously using x-ray and MRI guidance. MRI-guided drilling/curettage was performed in 4 cases and arthroscopic resection in 6 cases. RESULTS: All lesions were successfully treated using the MRI-guided method. All patients were free of pain after the treatment. There was no instance of recurrence during the follow-up period, which averaged 10 months. The effective dose for marking the lesion was between 0.0186 mSv and 0.342 mSV (mean 0.084 mSV). CONCLUSIONS: Our MRI diagnostics protocol, the MRI-guided drilling and the minimally invasive hip arthroscopy represent an alternative to CT-guided radiofrequency ablation in the treatment of osteoid osteomas. Radiation exposure can thereby be significantly reduced. Hip arthroscopy can also be used to treat secondary pathologies such as femoroacetabular impingement.

Nonunion of the radial neck in children: a rare but severe complication after fractures of the radial neck.

PURPOSE: Nonunion of the radial neck poses an enormous challenge for treating surgeons. It is a very rare complication of the radial neck with limited experiences. In this current major study, the authors report of their own experiences concerning this problem. METHODS: 11 patients with severe displaced radial neck fracture Metaizeau type IV with elbow dislocation and 2 ongoing fractures. 9 fractures had to be treated with open reduction, six with intramedullary nailing, two with K-wires and one with periosteal suture fixation. In two children, aged 4 and 5, the fracture was not diagnosed initially. The patients showed a successful reduction intraoperatively. RESULTS: All patients developed nonunion of the radial neck. 9 out of 11 children presented with pain and 5 out of 11 with valgus deformity. All children underwent surgical management of the complications. 3 children received a debridement of the elbow joint with resection of the fragmented radial head. 7 cases needed a following reduction, spongiosa-plasty and periosteal flap reconstruction and plate osteosynthesis. One patient received radial intramedullary pinning. All nonunions showed reunion. All patients with obtained radial head showed significant improvement concerning complaints and range of motion. Only one child showed a slight deterioration in range of motion. Children with resected radial head showed good range of motion but complaints and instability in loaded joint needing further surgical treatment. CONCLUSION: Treatment of radial neck nonunion in children should not be delayed until pain, deformity and limited function occurs because this goes along with severe transition of the radial head right up to bone atrophy.

Treatment of nonunion after forearm fractures in children: a conservative approach.

PURPOSE: Nonunions are a very rare complication after surgical treatment of displaced forearm fractures in children, but can occur in both the radius or ulna. The aim of this study is to evaluate predisposing factors for non-unions and to discuss treatment options. METHODS: We conducted a retrospective analysis of all patients who were treated primarily or secondary at our institution for nonunion after forearm fractures and operative treatment. Therefore, we retrospectively reviewed the medical charts and radiographs of affected patients from 1990 to 2020. We analysed demographic and fracture-related data as well as treatment options. RESULTS: Twenty-seven cases were identified. Median age was 12 years (7-16 years). The ulna was affected in 20 cases and the radius in 7. The most common location for ulna nonunion was the middle third of the shaft, and for the radius the mid and distal shaft. In 21 cases an open reduction was required. In 9 cases technical problems were identified. In most cases (26/27) a hypertrophic nonunion occurred. 10 of 27 (37%) nonunions healed without any surgical management after 9 (7-15) months. The median age of the conservatively managed group was 10 (6-13) years, younger than in the group with managed with reoperation [median 13 (7-16) years]. Indications for surgical intervention were increasing deformity, pain and limitation of movement. CONCLUSION: Open reduction and technical problems seem to be influencing factors. A conservative approach can be adopted in asymptomatic patients, otherwise an operative management, constituting plate osteosynthesis with or without bone grafting, should be performed.

Pseudo paralysis of the shoulder and increased C-reactive protein are predictive factors for septic shoulder in children superior to other clinical symptoms: a retrospective case series of 25 patients.

PURPOSE: The aim of the study was to evaluate predictable parameters with the highest sensitivity used in the diagnosis of children septic shoulder arthritis. METHODS: All children treated in our paediatric orthopaedic hospital between 2000 and 2017 with intraoperative verified septic arthritis of the shoulder were included in this retrospective study. Diagnostic procedures e.g. ultrasound, MRI, radiograph or blood samples as well as typical clinical symptoms were evaluated as predictable parameters for septic shoulder arthritis in paediatric patients. Descriptive statistics as well as sensitivity analysis were performed. RESULTS: In all, 25 children, 20 boys and five girls, aged from eight days to 15 years, were included for further statistical analysis. All parameters included were tested for sensitivity with binomial confidence intervals (Cis) of 95%. Predictive parameters with highest sensitivity were pseudo paralysis (100%, CI 0.86 to 1.00) and C-reactive protein (CRP) (96%, CI 0.79 to 0.99) superior to temperature (52%, CI 0.3 to 0.73), white blood count (11%, CI 0.01 to 0.34), radiograph (21%, CI 0.04 to 0.50), ultrasound (71%, CI 0.47 to 0.88) or MRI (100%, CI 0.78 to 1.00). CONCLUSION: The diagnosis of a septic arthritis of the shoulder in children can be challenging for the clinician and especially for the resident doctor. Clinical symptoms such as pseudo paralysis and increased CRP level must be considered as predictive markers not to delay further diagnostics and treatment. LEVEL OF EVIDENCE: IV.

Bilateral Tibial Tubercle Avulsion Fractures in Children - Clinical Results of a Rare Fracture. / Die bilaterale Avulsionsfraktur der Tuberositas tibiae ­ klinische Ergebnisse einer seltenen Verletzung im Wachstumsalter.

BACKGROUND: Tibial tubercle avulsion fractures are rare, they represent less than 1% of all physeal fractures. Compared to monolateral tibial tubercle avulsion fractures, bilateral occurrence is even rarer. The purpose of this study is to report about the so far largest group of bilateral avulsion fractures and to compare them to unilateral fractures as well as to current literature. METHOD: All patients who suffered from bilateral tibial tubercle fractures between January 2009 and March 2019 were included. All medical records and radiographs were reviewed and a clinical follow-up was performed. The examined criteria were age, gender, mechanism of injury, classification, risk factors, complications, management and outcomes. Clinical outcome was measured using the well established Tegner activity scale and Lysholm-Gillquist score. The same criteria were analyzed in a literature review of bilateral tibial tubercle fractures to compare our results to available literature. RESULTS: We found four children with bilateral tibial tubercle avulsion fractures. All patients were male with a mean age of 14.5 ± 0.7 years (13 - 15). Mean follow-up examination was 13.6 ± 6.5 months (8 - 29) after surgery. The avulsions occurred during jumping activities in all cases. All children could no longer stand or move because of sudden pain in the knee. We found type IV fractures in three cases, type III fractures in four cases and one type V fracture according to the Ogden classification. All children were treated by open or closed reduction and stabilization with screws or K-wires. Follow-up showed complete fracture healing without complications in all patients. There were no changes in Tegner activity scale and Lysholm-Gillquist Score and knee function comparable to prior to the accident was achieved in all cases. CONCLUSION: Good clinical results without restrictions regarding function of the knee joint can be achieved by direct operative treatment of bilateral tibial avulsion fractures. A reduction in sporting activity has not to be expected. There were no differences between bilateral or unilateral tibial tubercle avulsion fractures.

The role of the labrum in early treatment of unstable developmental dysplasia of the hip.

The objective of the paper is to analyse the role of the labrum with particular attention to its morphological changes in unstable dysplastic hips during treatment.Between January 2013 and December 2015, data were collected on 86 unstable, dysplastic hips, which were divided into type D (n = 13), type III (n = 49) and type IV (n = 24). The labrum was evaluated with ultrasound examination (US) for echogenicity and dimensions with inter-/intra-observer tests comparing the US images at diagnosis and at the end of treatment. Statistical analysis was performed.At the end of treatment of unstable, dysplastic hips, the labrum was more echogenic with a frequency of 97% and was larger with a frequency of 96%.The labrum has an active stabilizing role in unstable dysplastic hips and it undergoes a statistically significant increase of echogenicity and dimensions after treatment. Cite this article: EFORT Open Rev 2019;4 DOI: 10.1302/2058-5241.4.180053.

[S2-Guideline: Pediatric Flat Foot]. / S2-Leitlinie: der kindliche Knick-Senk-Fuß.

In pediatric flat foot a differentiation has to be made between the flexible and the rigid form. The diagnosis is based on the history, clinical examination as well as pedobarography, gait analysis and imaging techniques. It is important to rule out neuropediatric conditions such as muscular dystrophies, Ehlers-Danlos- or Marfan syndrome. In children six years of age and younger a flexible flat foot is nearly always physiological (97% of all 19 months old children). Up to the age of ten years the medial column of the foot is developing. Only a minority of children (4% in ten year olds) has a persistent or progressive deformity. Beyond to age of ten there is a danger of deformity decompensation as well as an increased rigidity. Only a minority of children develops some pain (< 2%). A clear risk factor for persistent pediatric flat foot is obesity (62% of six year old children with flat foot are obese). Pathogenetic factors include muscular, bony or soft tissue conditions. However, there specific rule is still unclear. Prevention consists in a thorough parent information about the normal development as well as encouragement of regular sportive activities. Soft and large enough shoes should be carried as a protection. Barfoot walking has to be encouraged on uneven grounds. If physiotherapy is needed different methods can be applied. Orthosis treatment should include a proprioceptive approach. Surgical interventions in children are rare. If surgical treatment is planned a detailed algorhythm should be used before utilizing one of the many different surgical methods.

Clubfoot associated with preaxial polydactyly.

We report on three children with bilateral, congenital clubfoot. Four of the six clubfeet were associated with preaxial polydactyly. Five of the six clubfeet were treated without extensive surgery. A plantigrade foot was achieved, even in the three clubfeet with polydactyly, using serial casting and percutaneous Achilles tenotomy. Casting was adapted according to the existing polydactyly. One case with tibial hemimelia and a complex clubfoot deformity with preaxial tarsal polydactyly required more comprehensive surgery. A foot with good weight-bearing function was also achieved in this case following resection of the accessory medial ray, including resection of the accessory tarsal bones and posterior release. Remaining limitations in mobility were ascribed to hindfoot pathologies.

Mathematical modeling of biochemical systems with PottersWheel.

The program PottersWheel has been developed to provide an intuitive and yet powerful framework for data-based modeling of dynamical systems like biochemical reaction networks. Its key functionality is multi-experiment fitting, where several experimental data sets from different laboratory conditions are fitted simultaneously in order to improve the estimation of unknown model parameters, to check the validity of a given model, and to discriminate competing model hypotheses. New experiments can be designed interactively. Models are either created text-based or using a visual model designer. Dynamically generated and compiled C files provide fast simulation and fitting procedures. Each function can either be accessed using a graphical user interface or via command line, allowing for batch processing within custom Matlab scripts. PottersWheel is designed as a Matlab toolbox, comprises 250,000 lines of Matlab and C code, and is freely available for academic usage at www.potterswheel.de .

The talar axis-first metatarsal base angle in CVT treatment: a comparison of idiopathic and non-idiopathic cases treated with the Dobbs method.

PURPOSE: Congenital vertical talus (CVT) appears as an idiopathic or non-idiopathic deformity. In this study, we analysed the talar axis-first metatarsal base angle (TAMBA) values of idiopathic and non-idiopathic CVT cases treated with the Dobbs method. MATERIALS AND METHODS: Between January 2007 and July 2012, 20 cases of CVT were treated, starting with a manipulation, casting and a minimally invasive surgical approach. We analysed retrospectively the TAMBA values in idiopathic and non-idiopathic CVT. As a new indicator for the mobility in the talonavicular complex, we used the difference of the TAMBA in neutral position and the TAMBA in plantarflexion. TAMBA measurements of CVT successfully treated with the Dobbs method were compared to TAMBA values of CVT unsuccessfully treated using a minimally invasive approach. RESULTS: Out of 20 CVT, 14 were successfully treated with the Dobbs method. Of these 14, five feet were non-idiopathic and nine feet were idiopathic. Six feet did not have complete correction following the Dobbs protocol, and were associated with arthrogryposis or caudal regression syndrome. The initial TAMBA in idiopathic feet ranged from 70 to 110° (mean 88°). The TAMBA in non-idiopathic feet ranged from 75 to 128° (mean 105). Feet successfully treated with the Dobbs method had an initial TAMBA between 74 and 110° (mean 87°). Feet unsuccessfully treated with the Dobbs method had an initial TAMBA between 95 and 128° (mean 118°).The measurement difference between the TAMBA in neutral and plantarflexion positions in cases unsuccessfully treated with the Dobbs method were smaller compared to values of feet successfully treated with the Dobbs method. These differences were statistically significant (p < 0.0001). CONCLUSION: In our series, the success of the Dobbs method in CVT treatment depended on the flexibility in the talonavicular complex. The TAMBA value and TAMBA difference (TAMBA neutral minus TAMBA plantarflexion) express the flexibility in the talonavicular joint and could be predictive for the success of a minimally invasive treatment. Only in a few cases is the success of the Dobbs method limited. These feet are associated with a TAMBA greater than 120° in neutral position and, particularly, a TAMBA difference smaller than 25°.