Dmitry Popkov

Flexible Intramedullary Nail Use in Limb Lengthening

Background The aim of this study is to evaluate the influence of the external fixation associated with flexible intramedullary nailing (FIN) on the healing index (HI) in limb lengthening. Methods We compared the healing index between 2 groups of children undergone the lengthening of upper and lower limbs carried out with the Ilizarov external fixator alone (group I, 194 cases of lengthening) or with the combination of the Ilizarov external fixator and intramedullary nailing (group II, 92 cases). Two nails of the diameter from 1.5 to 2.0 mm with the ray of curvature about 40 degrees to 50 degrees were used for the intramedullary nailing. Results The HI was less in every subgroup of Group II compared with Group I. A significant difference was noted in congenital pathologies: monofocal monosegmental lengthening at the level of femur and forearm, bifocal lengthening of the tibia, polysegmental lengthening; and in acquired discrepancy: monofocal tibial lengthening, bifocal femoral lengthening, and the forearm lengthening. The reduction of HI was between 60% and 85% in congenital pathologies: monosegmental femur and forearm, bifocal femur and tibia lengthening; and in acquired discrepancy: femur, tibia, humerus and forearm monosegmental lengthening, humerus and tibia bifocal lengthening, and polysegmental in upper and lower limbs. This difference varies from 1.9 days/cm to 19.1 days/cm. That means that the duration of the external fixator was decreased of 20% to 33% of the number of days between the Group I and the Group II. Maximum diminution of HI was noted for monofocal acquired forearm cases (51.3%) and bifocal acquired femoral lengthening cases which (59.9%). Conclusions The flexible intramedullary nailing allows adding multiple advantages to the method of limb lengthening with the external fixator. Correctly applied the FIN indeed respects the bone biology that is essential during the limb lengthening. The major effect of application of the combination of Ilizarov frame fixation with FIN is a significant decrease of duration of the external osteosynthesis. Level of Evidence II.

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.

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.

Elastic intramedullary nailing as a complement to Ilizarov's method for forearm lengthening: A comparative pediatric prospective study

PURPOSE Most of the techniques for forearm lengthening involve external fixation to achieve stability and provide progressive distraction. We introduce the use of elastic stable intramedullar nailing (ESIN) in combination with external circular assembly for the procedure. The purpose of this prospective study was to compare Ilizarovs classical technique with this combined technique. METHODS Fifty-seven patients, with forearm length discrepancies or deformities either congenital or acquired, were prospectively followed-up. Patients were divided in two groups: 35 had only external fixation, and 22 had external fixation-ESIN combined techniques. Patients were assessed for clinical and radiographic outcome with a mean follow-up of 21 months after external device removal. RESULTS Overall lengthening was 45.0mm. Healing index (HI) was 22.2d/cm with the combined technique, and 32.0 d/cm with external fixation. HI was 30% better when ESIN was used, for congenital and for overall cases. Combined technique has a lower complication rate. CONCLUSION Although forearm lengthening still remains a time-consuming procedure, ESIN can shorten external fixator wearing time. No additional complication occurred and bony complications seem to be limited by the nails. We recommend this technique, which we now use for most of our patients undergoing limb lengthening. LEVEL OF EVIDENCE Level IV.

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

INTRODUCTION During progressive lower limb lengthening in the management of Olliers 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 Olliers disease. LEVEL OF EVIDENCE Level III, comparative retrospective study.

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.

Current approaches to flexible intramedullary nailing for bone lengthening in children

Limb-length discrepancies and extremity deformities are among the most common non-traumatic orthopaedic conditions for which children are hospitalised. There is a need to develop new treatment options for lower-limb length discrepancy in order to ameliorate treatment outcomes, avoid or reduce rates of complication and provide early rehabilitation. The authors report on the basic principles, experimental and clinical data, advantages, problems and complications of a combined technique associating the Ilizarov method and flexible intramedullary nailing (FIN) in limb lengthening and deformity correction in children. They describe features of the use of hydroxyapatite-coated intramedullary nails in patients with certain metabolic bone disorders and in cases where bone consolidation has been compromised. The advantages of bone lengthening using a combined technique (circular fixator plus FIN) are a lower healing index, quicker distraction-consolidation, a reduced rate of septic and bone complications, the ability to correct deformities gradually and the increased stability of bone fragments during the external fixation period and after frame removal.

The use of flexible intramedullary nails in limb lengthening

ABSTRACT Introduction: Lower and upper limb length discrepancy and deformity, congenital or acquired, are amongst the most common conditions in children for orthopaedic referral. Over the last twenty years, surgical techniques have evolved in an attempt to decrease Healing Index and minimise these complications. Areas covered: The flexible intramedullary nailing (FIN) is a minimally invasive intramedullary osteosynthesis. In combination with an external fixator, it is appropriated for pediatric bone lengthenings and lengthening of bones of small diameter in adults. In the study the Scopus and/or PubMed indexed publications about this combined technique were analyzed. Expert commentary: The use of titanium or stainless steel or hydroxyapatite-coated bent elastic nails is appropriate in limb lengthening for congenital and acquired limb length discrepancy. Hydroxyapatite-coated FIN should be applied for long-term reinforcement of lengthened bone in patients with metabolic bone disorders, skeletal dysplasias with compromised bone formation. Osteoinductive surface of nails is favorable for bone formation and as well as for stable position of nails without risks of migration in long-term follow-up. The FIN is an unique intramedullary fixation which respects the bone biology which is mandatory for a good bone consolidation.

Residual bone growth after lengthening procedures

The prognosis of limb length discrepancy is a major subject in paediatric orthopaedic surgery. The strategy depends on the prognosis and must be adapted to each patient. The residual growth of the lengthened segment often remains unknown, but is dependent on age, the percentage of lengthening and other factors. Using a large cohort of 150 children who had undergone bone lengthening procedures, we describe five patterns of post-intervention growth and identify factors that are favourable for normal residual growth. The criteria for bone lengthening which should maintain good residual growth are—bone age at lengthening should be before the pubertal growth spurt; the interval between two lengthening procedures should be over three years; the percentage of lengthening should be <30% of the initial segment; and no more than two lengthening procedures should be carried out during infancy.