Voluntary femoro-tibial subluxations: a benign differential diagnosis in the snapping knee of a child.

PURPOSE: Voluntary femoro-tibial subluxation is a rare entity predominantly found in pretoddlers. It presents as a dynamic phenomenon with uni- or bilateral audible snapping of the knee, often in a context of fatigue or irritation at the end of the day. The aim of the study was to observe the evolution and recovery in these patients. METHODS: Ten children were included. Other causes of dislocating joints and pathologies with snapping of the lateral meniscus were excluded from this study. Six-week immobilisation with a splint at 70° of knee flexion was primarily recommended to all patients. RESULTS: The mean age at onset of symptoms was 10 months. Forty percent of the patients presented with bilateral symptoms. Clinically, four patients were hyperlax. In all patients, subluxations could be reproduced passively by rotating the foot externally and advancing the internal tibial plateau anteriorly. Three of the patients were treated with a dorsal splint and experienced significantly less or cessation of symptoms. Two patients underwent surgery, one for a concomitant anterior cruciate ligament (ACL) rupture and meniscus tear that worsened the symptoms, another for concomitant patella dislocation and a meniscus tear. One patient's parents refused treatment and four patients experienced less symptoms at the time of consultation and were not immobilized. Except for the two patients undergoing surgeries, no sequelae were observed. In general, the symptoms got less frequent when the patient began to walk. CONCLUSION: Voluntary femoro-tibial subluxation in children is a rare and benign condition that often resolves spontaneously without sequelae. The risk of meniscus tear should, however, be considered if subluxations do not cease. LEVEL OF EVIDENCE: IV.

Flexed-knee gait in children with cerebral palsy: a long-term follow-up study.

Aims: The purpose of this study was to evaluate the long-term outcome of adolescents with cerebral palsy who have undergone single-event multilevel surgery for a flexed-knee gait, followed into young adulthood using 3D motion analysis. Patients and Methods: A total of 59 young adults with spastic cerebral palsy, with a mean age of 26 years (sd 3), were enrolled into the study in which their gait was compared with an evaluation that had taken place a mean of 12 years (sd 2) previously. At their visits during adolescence, the children walked with excessive flexion of the knee at initial contact and surgical or therapeutic interventions were not controlled between visits. Results: Based on the change in flexed-knee gait over approximately ten years, improvements were seen in increased Gait Deviation Index (p < 0.001) and decreased flexion of the knee at initial contact (p < 0.001). Greater popliteal angle (p < 0.001), reduced Gross Motor Function Measure section D (p = 0.006), and reduced speed of gait (p = 0.007) suggested a mild decline in function. Quality-of-life measures showed that these patients fell within normal limits compared with typical young adults in areas other than physical function. Conclusion: While some small significant changes were noted, little clinically significant change was seen in function and gait, with gross motor function maintained between adolescence and young adulthood. Cite this article: Bone Joint J 2018;100-B:549-56.

[Osteoid osteoma on distal phalanx tip of second toe, without scintigraphy fixation]. / Ostéome ostéoïde de la phalange distale sans hyperfixation scintigraphique.

Osteoid osteoma is a very small painful, benign tumor, located preferentially on long bones. Cases on the phalanxes of the toes are very rare. Pain takes up nearly all the clinical presentation. Poor clinical signs and atypical location make diagnosis difficult and delayed. Sometimes, it can be confused with local infection. Various additional tests are described to help diagnosis. Technetium 99-m scintigraphy coupled with CT is the key exam with high sensitivity and morphological accuracy. We report on the case of a 10-year-old boy with an atypical location of osteoid osteoma on the distal phalanx tip of the second toe, without scintigraphy fixation and obvious nidus on X-ray and CT scan.

ACL reconstruction in children: a transphyseal technique.

The annual incidence of ACL tears is increasing steadily in pediatric patients. Chronic anterior instability causes meniscal lesions at a frequency that increases significantly with the injury-to-surgery interval. Conservative therapy, simple suturing, and isolated extra-articular tendon reconstruction are associated with high failure rates. Intra-articular arthroscopy-assisted tendon reconstruction is a good treatment method, although several different techniques have been described. We used a transphyseal technique with a hamstring tendon graft to treat 14 knees in 13 patients with a mean age of 13 years and 7 months. Mean injury-to-surgery interval was 6 months. Strict compliance with technical rules is required when using this technique. Bone tunnel diameter must not exceed 8 mm. Bone tunnels must be as vertical and central as possible. The fixation material must not bridge the physis (at the femur, cortical fixation; and at the tibia, fixation using a resorbable screw no longer than 25 mm combined with a staple). Meniscal lesions were present in half the knees and meniscal preservation considered mandatory. Conservative treatment of concomitant lesions was performed routinely. After a mean follow-up of 15 months, no recurrent tears or revision procedures for meniscectomy had been recorded. The IKDC grade was A or B in 93% of knees. The mean subjective IKDC score was 83.3 and the Lysholm score was in the excellent or good range in 93% of knees. Of the 14 knees, 2 exhibited signs suggesting femoral epiphysiodesis, with 4° of valgus deformity compared to the contra-lateral knee and no clinical consequences. Transphyseal reconstruction with open physes conducted in strict compliance with technical rules can be performed to control the instability and preserve the menisci. Nevertheless, this technique carries a risk of epiphysiodesis, chiefly at the femur.

The anatomical basis for anterior interosseous nerve palsy secondary to supracondylar humerus fractures in children.

INTRODUCTION: Various studies have found that 6.6 to 31% of supracondylar elbow fractures in children have nerve-related complications. One-third of these are cases of anterior interosseous nerve (AIN) palsy that usually result in a deficit of active thumb and index flexion. The goal of this cadaver study was to describe the course of the AIN to achieve a better understanding of how it may get injured. MATERIALS AND METHODS: On 35 cadaver specimens, the median nerve and its collateral branches destined to muscles were dissected at the elbow and forearm levels. The distance at which the various branches arose was measured relative to the humeral intercondylar line. Interfascicular dissection of the AIN was used to map its distribution within the median nerve. RESULTS: The AIN arises at an average of 45 mm from the humeral intercondylar line. Before emerging from the median nerve, the AIN fascicles were always found in the dorsal part of the median nerve. After emerging, the AIN was divided into two zones. Zone 1 was the transitional portion from its exit point until its entrance into the interosseous space, where it changes direction. Zone 2 was the interosseous portion between the radius and ulna that comes into contact with the anterior interosseous membrane to which it is attached over its entire length until it ends in the pronator quadratus (PQ) muscle. The muscle branches of the AIN destined for the flexor pollicis longus (FPL) and flexor digitorum profundus (FDP) muscles mostly originated in Zone 1, which is the transitional portion between the median nerve and the fixed Zone 2. The branches destined to the pronator teres (PT) and flexor carpi radialis (FCR) originating from the median nerve are more proximal and superficial. DISCUSSION: The injury mechanisms leading to selective AIN palsy secondary to supracondylar elbow fracture in children are probably the result of two factors: direct contusion of the posterior aspect of the median nerve, and thereby the AIN fascicles, by the proximal fragment; stretching of AIN in Zone 1, which has less ability to withstand stretching than the median nerve and its other branches because the AIN is fixed in Zone 2. CONCLUSION: Details about the origin and course of the AIN can explain the high percentage of AIN palsy in supracondylar elbow fractures in children. LEVEL OF EVIDENCE: Level IV. Anatomic study.

Analysis of segmental residual growth after progressive bone lengthening in congenital lower limb deformity.

INTRODUCTION: The issue of prognosis in limb length discrepancy in children affected by congenital abnormality remains a subject of concern. Therapeutic strategy must take length prediction into account, to adapt equalization techniques and the timing of treatment. Initial prognosis, however, may need revising after completion of one or several surgical interventions on the pathologic limb. The aim of this study was to determine the different types of growth response that a bone segment can present after progressive lengthening in case of congenital limb length discrepancy. MATERIALS AND METHODS: A series of 114 bone lengthenings with external fixator, performed in 36 girls and 50 boys with congenital lower limb length discrepancy, was retrospectively analyzed. Bone segment growth rates were measured before lengthening, during the first year after frame removal and finally over long-term follow-up, calculating the ratios of radiological bone length to the number of months between two measurements. Mean follow-up was 4.54±0.2 years. RESULTS: Changes in short- and long-term growth rate distinguished five patterns of bone behavior after lengthening, ranging from growth acceleration to total inhibition. DISCUSSION: These five residual growth patterns depended on certain factors causing acceleration or, on the contrary, slowing down of growth: age at the lengthening operation, percentage lengthening, and minimal period between two lengthenings. These criteria help optimize conditions for resumed growth after progressive segmental lengthening, avoiding conditions liable to induce slowing down or inhibition, and providing a planning aid in multi-step lengthening programs. LEVEL OF EVIDENCE: Level IV. Retrospective study.

Classification of complications after progressive long bone lengthening: proposal for a new classification.

INTRODUCTION: Long bone lengthening surgery using progressive surgical methods has been the source of frequent complications. Some authors have classified these complications either descriptively, according to the date of onset after the operation, or based on their severity. The Caton classification (1985) has had the virtue of contributing the notion of the treatment contract stipulating the objective to reach in treatment. Within the context of the preoperative information delivered to patients and their family, this contract can be improved by adding a notion of maximum treatment duration. The objective of this study was therefore to propose a classification that includes honoring a triple contract associating the planned gain in bone length, the duration of treatment, and the occurrence of sequelae. MATERIALS AND METHODS: The classification of complications proposed includes four grades: grade I: triple contract honored, including a few treatments without general anesthesia; grade II: triple contract fulfilled, but with unplanned interventions under general anesthesia; grade III: the time stipulated was not honored because the time to obtain bone union was too long or because the program was interrupted; grade IV: sequelae are present. This classification was assessed based on a consecutive series of 34 surgical procedures in 32 patients (two patients underwent two lengthening procedures during this period) at 43 bone segments associating progressive lengthening with external fixation or with nail lengthening. The grade of each complication was determined by each of the authors according to the classification proposed and other classifications reported in the literature (Caton, Paley, Popkov, and Donnan). RESULTS: Approximately one-third (10) of the 34 lengthening procedures did not present any complications. Two-thirds (24) presented 30 complications. Consensus was obtained between all the authors on the grades proposed for our classification and the Caton classification, but consensus was not reached with the other classifications in which part of the interpretation was subjective (Paley, Popkov, and Donnan). DISCUSSION: The classification proposed required respecting predetermined objectives during limb lengthening surgery based on a triple contract: gain, duration, and function. It is reliable and reproducible by different operators because the criteria are objective. It can also be applied to diverse surgical techniques, whether with external fixation and/or internal osteosynthesis. LEVEL OF EVIDENCE: Level IV: retrospective study or historical series.

Early complications with flexible intramedullary nailing in childhood fracture: 100 cases managed with precurved tip and shaft nails.

BACKGROUND AND PURPOSE: Diaphyseal and metaphyseal fractures in children are frequently treated with the flexible intramedullary nailing (FIN) method. The aim of this study was to record postoperative complications and outcome in consecutive fracture patients treated with the new precurved tip and shaft nails and dedicated ergonomic instrumentation. METHODS: We report the analysis of 100 consecutive fractures followed up for a minimum of 6 months. Ninety-seven children were included, comprising 77 shaft and 23 metaphyseal fractures. Demographic data, duration of surgery, nail and medullary canal diameter, date of nail removal, clinical assessment, follow-up radiographs and all complications were recorded. RESULTS: Mean age was 9.7 years, and mean body weight 35.1 kg. Twenty-one fractures had associated lesions. Mean duration of surgery was 42.4 minutes. Nail removal was at a mean 6.1 months. Twelve percent of patients had complications, with six insufficient reductions, one delayed union, one non-union, one iterative fracture, and three skin impingements. Unexpected surgical revision was required in seven cases. At follow-up, only one patient showed functional impairment, with 20° pronation loss, and three showed more than 10° axial deviation on X-ray. CONCLUSION: The low rate of skin impingement compared with the literature may be due to the new dedicated instruments. We believe that other complications can be avoided if one follows the FIN principles, avoiding weak assembly due to an insufficient nail/medullary canal diameter ratio, which is a limiting factor for indications in adolescents. The surgeons reported that precurved shaft nails facilitated the FIN procedure, although this subjective judgment may be due simply to the novelty of the nails. LEVEL OF EVIDENCE: Level IV. Retrospective study.

Hip septic arthritis in children: assessment of treatment using needle aspiration/irrigation.

INTRODUCTION: This retrospective series evaluated the surgical treatment of hip arthritis in children by needle aspiration-irrigation alone. PATIENTS AND METHODS: Forty-three cases of septic hip arthritis were treated by needle aspiration-irrigation under general anesthesia associated with intravenous then oral administration of antibiotics. Clinical and biological criteria at admission, during hospitalization and at final follow-up were studied to identify any criteria carrying a predictive value for unsuccessful needle aspiration-irrigation. RESULTS: Thirty-eight hips had a favorable outcome in this series, while secondary open arthrotomy was required in five hips for further irrigation. Common criteria found in the group requiring open arthrotomy were a diagnosis delay of at least 6 days between initial clinical symptoms and treatment as well as markedly abnormal biological results at admission. A threshold for the predictive value of certain variables was identified including C-reactive protein above 100, white polynuclear blood count above 15000, and sedimentation rate above 25 in the first hour and 50 in the second hour. DISCUSSION: Treatment modalities for septic arthritis of the hip remain controversial in children and various techniques have been shown to be effective in the literature. Needle aspiration-drainage, the least invasive of these, has been shown to have good results, even in the hip, even though this is a deep, tight, joint which is known to be difficult to drain. Prognostic criteria are difficult to identify, however all authors agree that delayed treatment makes evacuation of intra-articular debris especially difficult. CONCLUSION: Needle aspiration-irrigation is effective in septic arthritis of the hip, as long as basic principles are followed. Delayed treatment and certain biological criteria should be taken into account when selecting a treatment, since negative predictive criteria identified in this series were present in the five hips requiring secondary arthrotomy.

Child calcaneonavicular coalitions: MRI diagnostic value in a 19-case series.

INTRODUCTION: In case of hindfoot pain, diagnosis of calcaneonavicular tarsal coalition may be missed on X-ray due to the absence of any visible synostosis. All other possible etiologies (too-long anterior process (TLAP) of the calcaneum, synchondrosis, syndesmosis) must be investigated. The literature tends to recommend imaging associating standard X-ray and CT, and possibly bone scintigraphy. MRI is, however, also worth assessing, due to the many non-osseous forms calcaneonavicular pain may take. MATERIAL AND METHODS: Thirty-two cases of surgically treated calcaneonavicular tarsal coalition were studied. Nineteen cases, in 14 children, over a 10-year period, showed no visible synostosis on initial standard X-ray. In seven cases, bone scintigraphy was performed, CT in seven and MRI in 12. On the basis of the literature, our attitude was in favor of X-ray associated to CT in our early experience. Repeated diagnostic difficulties, however, led us to replace CT by MRI in case of foot pain combined to symptomatology suggestive of coalition. RESULTS: The series comprised four cartilaginous forms, four fibrous forms and eight TLAPs. In 10 of the 19 feet, radiology was strictly normal, the others showing indirect osseous signs. Only three of the seven scintigraphies showed hyperfixation. CT-scan enabled diagnosis in seven cases (two synchondroses and five rudimentary forms), and missed diagnosis in four (two cartilaginous and two fibrous forms). Second intention MRI showed two synchondroses and two syndesmoses. In the light of these 11 cases, a subsequent series of eight feet was assessed by MRI in first intention, obtaining systematic diagnosis. In all the feet of the series, the symptomatic coalition was treated by surgery, allowing peroperative findings to be compared with the imaging data. DISCUSSION: Given a rigid and painful foot syndrome suggestive of tarsal coalition, two diagnostic situations arise: (a) the clinical aspect is suggestive and standard X-ray enables diagnosis; (b) the clinical aspect is suggestive, but radiography proves non-contributive, in which case we recommend MRI with sagittal, frontal and axial slices in gadolinium-enhanced T1-weighted and fat-sat T2-weighted sequences, revealing direct (cartilaginous or fibrous coalition) or indirect signs (peripheral inflammation, osteomedullary edema, chondral lesion) unobtainable on CT scans. MRI is particularly effective in as much as most of the children concerned will not have reached bone maturity. CONCLUSION: We consider MRI to be the most effective means of precise diagnosis (causes and consequences) of tarsal coalition, especially for calcaneonavicular locations. It entails minimal invasion and irradiation, at a lower cost than CT associated to scintigraphy. LEVEL OF EVIDENCE: IV. Diagnostic study.

Ollier's disease limb lenghtening: should intramedullary nailing be combined with circular external fixation?

INTRODUCTION: During progressive lower limb lengthening in the management of Ollier's disease, the mean bone-healing index usually reported in the literature stands around 35 days/cm. One of the therapeutic objectives is to reduce the duration of the external fixation. HYPOTHESIS: The use of an elastic stable intramedullary nailing system (ESIN) combined with a circular external fixator significantly reduces the healing index. MATERIAL AND METHODS: Two groups of patients were compared. In group I, seven patients were operated on for progressive limb lengthening using a circular external fixator associated with an ESIN system: four monosegmental femoral lengthenings, one monosegmental tibial lengthening and two polysegmental femorotibial lengthenings. Nailing was performed via two intramedullary nails already used in traumatology. The date of external fixator removal coincided with that of radiographic healing. The nails were left in place. Group II included 37 patients who underwent limb lengthening by means of an external fixator only. The healing index was calculated and complications were analysed in both groups. RESULTS: The mean healing index (HI) values were: in group I: 23.3 days/cm for the femur, 22.4 days/cm for the tibia and 11.6 days/cm for polysegmental lengthenings ; in group II: 31.6 days/cm for the femur, 35.7 days/cm for the tibia and 19.9 days/cm for polysegmental lengthenings. Group I demonstrated a statistically significant decrease in the HI for monosegmental femoral lengthenings. CONCLUSION: A substantially reduced duration of external fixation, limited postoperative complications and prevention of later pathologic fractures are the reported advantages of the associated use of a circular external fixator with an ESIN system in the management of Ollier's disease. LEVEL OF EVIDENCE: Level III, comparative retrospective study.

Is combining massive bone allograft with free vascularized fibular flap the children's reconstruction answer to lower limb defects following bone tumour resection?

PURPOSE OF THE STUDY: Bone tumours are frequent conditions in children, and their surgical resection may lead to extensive defects which reconstruction is often challenging. Indeed, local conditions do not promote bone healing, and the achieved surgical result requires to be life-lasting. Capanna suggested a reconstruction technique combining massive allograft and free vascularized fibular flap. The first one is intended to withstand mechanical stress, and the second one offers biological and vascular support to improve bone healing and prevent infections. MATERIAL AND METHODS: We report our experience with this technique when applied to the lower limb in a prospective study including seven children, with a mean follow-up of 44 months. RESULTS: Bone healing was achieved by one single procedure in 85.7% of the cases, usually 7 months after surgery. Six out of seven patients achieved a final and long-lasting outcome, five of them following a simple surgical history. Partial weight-bearing was post-operatively allowed at about 2 months, full weight-bearing was initiated at about 5.5 months. DISCUSSION: A low complication rate was reported despite the extent of the disease and the type of the surgical procedure. Capanna's combined reconstructive technique appears very efficient in the management of massive bone defects following tumour resection in children's lower limb. LEVEL OF EVIDENCE: Level IV. Retrospective therapeutic study.

[Bilateral upper femoral physis injury in a case of epilepsy in a young child]. / Décollement épiphysaire fémoral proximal bilatéral chez un nourrisson atteint d'épilepsie généralisée. A propos d'une observation.

Detachment of the proximal epiphyseal plate of the femur is a rare observation in infants. The context usually involves obstetrical injury or child abuse. There is however a high risk in certain children with epilepsy. Fractures and dislocations can occur during hypertonic seizures in a context of iatrogenic bone weakening due to drug treatments. Emergency reduction is required and requires a double fixation with osteosynthesis and plaster cast in order to reduce the risk of secondary displacement in this particular context. The risk of major impact on growth requires prolonged radiographic and clinical follow-up.

The practice of physical and sporting activity in teenagers with idiopathic scoliosis is related to the curve type.

Idiopathic scoliosis (IS) is correlated with a muscular disequilibrium of the spine and an alteration of balance control, efficient performance of the latter being necessary for physical and sporting activities (PSA). However, the type of the IS curve has different effects on muscle and on balance control according to the primary curve location. This study aimed to determine the relationships between IS type and PSA practice. One hundred and sixty-nine girl adolescents with IS [double major curve (DMC) scoliosis: n=74; single major curve (SMC) scoliosis: n=95] and 100 age-matched control girl adolescents completed an epidemiological questionnaire informing on curricular and extracurricular PSA. Adolescents with DMC scoliosis practised more PSA than those with SMC scoliosis. Moreover, among all PSA referenced, gymnastic activities are the most practiced PSA both in IS teenagers, whatever the curve type, and in controls. Besides, teenagers practising gymnastics were more numerous in those with DMC scoliosis than those with SMC scoliosis and controls. The highest proportion of adolescents with DMC scoliosis practising PSA, especially gymnastics, could be linked to the fact that they are less subject to scoliosis-related biomechanical repercussions leading to a better balance control, which is essential in these PSA.

Extensor retinaculum syndrome after distal tibial fractures: anatomical basis.

Fractures of the distal extremity of the tibia include physeal injuries among teenagers and more complex fractures among adults. Displacement causes the compression of the muscles located between the distal tibia and the superior extensor retinaculum (SER). Among the muscles of anterior compartment of the leg, the extensor hallucis longus (EHL) is particularly vulnerable due to the amount of muscle fibers extending under the SER. Consequently, a partial anterior compartment syndrome could result, affecting only the distal portion located under the SER. In clinical practice, Mubarak measured the intramuscular pressure isolated under the SER and suggested the physio-pathological hypothesis of a compression of distal muscle fibers. The aim of this study is to compare the ratios of anterior compartment muscle fibers extending under the SER. Twenty legs were dissected in order to study how much of these muscles extend under the SER, their passages possibly dividing into two of the SER, as well as their vascularization and their innervation. On the last seven legs, the engagement of the muscles were measured in the spontaneous position and with a dorsal flexion of 0 degrees . The posterior muscle fibers of this compartment always descend lower than the anterior fibers. EHL muscle fibers and those of the inconsistent fibularis tertius always extend under the retinaculum, unlike those of the tibialis anterior and of the extensor digitorum longus. The EHL muscle extends under the SER more than the other muscles. Its posterior fibers are longer when this muscle goes through a dividing into two of the retinaculum. Its vascularization seems lesser, which could explain why this muscle tends to suffer more. The deep fibular nerve innervates the anterior compartment of the leg, yet no nerve branches can be found under the upper edge of the retinaculum. In all cases, the muscle fibers do not extend as much under the SER in a 0 degrees of dorsal flexion. This anatomical study allows us to explain why the EHL is more likely to suffer from this partial compartment syndrome and confirms that when the latter occurs it is necessary, in all cases, to do emergency surgery opening the distal crural fascia and necessarily including the SER.

Why do idiopathic scoliosis patients participate more in gymnastics?

The influence of physical and sporting activities (PSA) on idiopathic scoliosis (IS) is still obscure. The aim of this study was to investigate whether such an influence exists and if so, to determine its characteristics. Two hundred and one teenagers with IS and a control group of 192 adolescents completed an epidemiological questionnaire. Those practising gymnastics were more numerous in the IS group than in the control group. Moreover, the practice of gymnastics was chosen before IS was diagnosed. As gymnastic activities are considered neither as a therapy nor as a precursor of IS, the distribution observed could be linked to a common factor that both increases the likelihood of IS and favors the practice of gymnastics. Joint laxity (JL) may be such a common factor, and was therefore tested (wrist and middle finger) on 42 girls with IS and 21 girls of a control group. IS patients, practising gymnastics or not, showed a higher JL than the control group practising gymnastics or not. Furthermore, the groups practising gymnastic activities did not show higher JL levels than the other groups. Children with a high JL could be drawn toward gymnastics because of their ability to adapt to the constraints of this sport. Girls with a high JL may therefore be prone to developing IS. The fact that most teenagers with IS practise gymnastics could be related to a higher JL.

The effect of inturning of the foot on knee kinematics and kinetics in children with treated idiopathic clubfoot.

OBJECTIVE: To assess the effect of internal foot progression angle (inturning) on knee dynamics in children with treated clubfeet. DESIGN: Prospective study dividing a population of clubfeet according to the factor inturning. BACKGROUND: Excessive internal or external foot progression angle increases knee flexion by a backward shift of the ground reaction force to the knee joint in children with cerebral palsy. Similarly, inturning in clubfeet was hypothesized to shift the ground reaction force backwards with reference to the knee joint, increasing the external knee flexion moment and the maximal knee flexion at stance. METHODS: Three-dimensional gait analysis was performed on 20 children with surgically treated clubfeet (n=28) to assess alterations of knee dynamics related to inturning (>7 degrees ) and on 13 normal children. RESULTS: Inturning occurred in 46% of the clubfeet and was associated during stance, at maximal knee flexion, to an increase in maximal knee flexion (+7 degrees ), external knee flexion moment (+60%) and related lever arm to the knee (+100%) and at minimal knee flexion, to a reduction in external knee extension moment (-62%) and related lever arm (-58%). Inturning was associated with a more frequent prolongation of internal knee extension moment and of rectus femoris activity exceeding 50% of stance. CONCLUSION: Inturning in clubfeet is associated with knee dynamics alteration, which might contribute to the long-term development of knee osteoarthritis. RELEVANCE: The therapeutic correction of inturning in clubfeet would be of importance if the consecutive knee dynamics alteration is shown by further studies to contribute to long-term degenerative knee pathology.