Simultaneous Lengthening Research Articles

Half-pin Breakage in Multiplanar External Fixators Used for Pediatric Deformity Correction.

Pediatric patients with leg length discrepancies and complex deformities may require multiplanar external fixators for correction. We have encountered 4 cases of half-pin breakage with the Orthex hexapod frame. The purpose of this study is to report factors associated with half-pin breakage and compare various deformity correction characteristics between 2 hexapod frames - Taylor Spatial Frame (TSF) and Orthex. Pediatric patients with lower extremity deformities treated with an Orthex or TSF at a single tertiary children's hospital between 2012 and 2022 were included for retrospective review. Variables compared between frame groups include frame configuration, half-pin/wire fixation, length achieved, angular correction, and frame time. There were 23 Orthex frames (23 patients) and 36 TSF (33 patients) included. Four Orthex and zero TSF had proximal half-pin breakage. The Orthex group was younger on average (10 vs. 12y, P =.04*) at the time of frame placement. The majority (52%) of Orthex frames were used for simultaneous lengthening and angular correction, while the majority (61%) of TSF was used for only angular correction. Orthex had more half-pins used for proximal fixation (median 3 vs. 2, P <0.0001*) and more frames with nonstandard configuration (7 (30%) vs. 1 (3%), P =0.004*). Orthex group had a longer total frame time (median 189 vs. 146 days, P =0.012*) and longer time required for regenerate healing (117 vs. 89d, P =0.02*). There were no significant differences in length gained, angular correction, or healing index between Orthex and TSF. Nonstandard configuration, increased number of proximal half-pins, younger age at index surgery, and increased lengthening were associated with pin breakage. This is the first study to report half-pin breakage while using multiplanar frames in pediatric lower extremity deformity correction. The Orthex and TSF groups consisted of significantly different patients and frame configurations, making it difficult to identify any specific cause for pin breakage. This study shows that pin breakage is likely caused by multiple factors and is associated with the increased complexity of deformity correction. Level III-Retrospective Comparison Study.

Does the technique of limb lengthening affect physeal growth in patient with achondroplasia? Comparison of the simultaneous and consecutive tibia and femur lengthening with external fixators.

We aimed to retrospectively investigate and compare patients who underwent bilateral simultaneous and consecutive lengthening surgery of the femur and tibia in terms of the effect on physeal growth. We hypothesize that compared with the sequential lengthening technique, simultaneous lengthening of the bilateral femur and tibia affects physeal growth to a greater extent. Twenty-six patients with achondroplasia who operated in our clinic between 1995 and 2015 for limb lengthening were included in the study. Fourteen patients with bilateral lengthening of the femur and tibia at the same time were named as simultaneous bilateral lengthening (SBL). Twelve patients with bilateral lengthening of the femur and then bilateral tibia lengthening in other sections or vice versa, at a different time was named consecutive bilateral lengthening (CBL). All patients were followed until at least 18 years old. The physeal arrest was measured with predicted final length at the first visit (investigated with the multiplier method), the total amount of lengthening, and final clinical, and radiological length. Mean limb lengthening was 145 mm (48.5%) and 151 mm (46.6%) for simultaneous and consecutive groups respectively. For lower extremity length, the first group reached 527.6 mm while the expected was 447.3 mm. Considering 151 mm lengthening, the mean growth disturbance for the SBL group was 70.7 mm and for the CBL group was 47.5 mm. For total height comparing between two groups, disturbance for height was 80.5 mm and 65.4 mm, respectively. Although there was no statistical difference, simultaneous bilateral femoral and tibial lengthening has more physiological physeal disturbance effects than consecutive lengthening in patients with achondroplasia.

A POLYOSTIC FORM OF FIBROUS DYSPLASIA: CORRECTION OF THE SHORTENED AND DEFORMED RIGHT UPPER LIMB WITH TSF EXTERNAL FIXATOR SYSTEM– CASE REPORT

Fibrous dysplasia (FD) is a congenital skeletal disorder characterized by the replacement of the bone marrow with fibrous tissue. FD may occur in isolation or association with endocrinopathies, and in that case, labeled McCune–Albright syndrome (MAS). FD can cause bone deformities or/and limb length discrepancies. The surgical intervention aims to correct limb deformities and length discrepancies while improving regional aesthetics. We report a case of a 14-year-old girl with FD that had affected her upper limbs. More characteristic had been the shortening of the right humerus (10 cm discrepancy from the left humerus) and the gun-stock deformity of the elbow. On the X-ray, a prominent feature was the shortening of the humerus and the valgus deformity of its distal end. The lengthening and correction of the deformity of the right humerus had been performed using the Taylor spatial frame (TSF) system. The software program had provided us with the estimated minimum correction time of 143 days for 7 cm humeral lengthening. A total of 157 days had been needed to lengthen and correct the deformity. The TSF system allows the simultaneous lengthening and correction of all the components of a multiplanar malformation of a limb and minimizes the required time.

Simultaneous Bilateral Femoral and Tibial Lengthening in Achondroplasia

Previous studies on lengthening for achondroplasia have reported bilateral extensive femoral lengthening followed by bilateral extensive tibial lengthening. To decrease trauma on soft tissues and joints, we propose bilateral simultaneous moderate femoral lengthening and moderate tibial lengthening followed by a similar repeat lengthening a few years later. Fifty patients with achondroplasia underwent 65 simultaneous bilateral femoral and tibial lengthening procedures. Segment lengthening amount and adverse events were obtained from medical records. Mean follow-up after bone healing was 35.6 months. Mean tibial lengthening was 52 mm; mean femoral lengthening was 72 mm. Average healing index was 1.4 months/cm for the tibia and 1 month/cm for the femur. Mean duration of treatment with external fixation was 6.7 months (range, 4.4–10.5 months). Thirty-eight (76%) of 50 patients experienced one or more adverse events during lengthening. We observed 78 adverse events, 35 (45%) of which required additional surgical procedures. All resolved by the end of treatment. Mechanical axis deviation improved from a mean of 15 mm medially to 8 mm medially. Simultaneous lengthening of four segments in patients with achondroplasia is a feasible strategy. Compared with isolated femoral or tibial lengthening, distributing the lengthening between the femur and tibia decreases total external fixator time.

Amine-rich quartz nanoparticles for Cu(II) chelation and their application as an efficient catalyst for oxidative degradation of Rhodamine B dye.

The study describes the loading of the quartz SiO2 nanoparticles (NPs) with (3-aminopropyl)triethoxysilane (APTES) linker with simultaneous lengthening of the linker through the terminal amine group by glutaraldehyde (GA). The reactive polyethylenimine (PEI) was introduced to the surface to increase the ability to capture Cu(II) ions. The composite got the abbreviation SiO2/PEI-Cu(II). The Cu(II) ions were the active center with a peroxo-complex activation state. The composite characterization included scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron-dispersive X-ray analysis (EDX), Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), and Brunauer-Emmett-Teller (BET) surface analyzer. The kinetics of the oxidative degradation of Rhodamine B (RhB) dye obeyed the pseudo-first order under flooding conditions. The reaction parameters including the catalyst dose, solution pH, initial concentration of reactants, and temperature got some attention. The obtained results showed that more than 91.7 ± 1% of RhB dye was degraded to CO2, NH4+, NO3-, H2O, and some inorganic acids after 30 min as confirmed by gas chromatography mass spectrometry and total organic carbon (TOC) measurements. Also, GC-MS spectra for water samples drawn from the reaction in successive periods had suggested a conceivable degradation pathway for RhB by hydroxyl radicals. Degradation starts with de-alkylation then carboxyphenyl removal followed by two successive ring-opening stages. Both the effects of the catalyst recycling and treated water reusability on the reaction rate were studied. The catalyst provided noticeable stability over three consecutive cycles.

Combined antegrade femur lengthening and distal deformity correction: a case series

BackgroundLeg length discrepancy is often associated with distal femur angular deformities such as valgus or flexion. This study aims to report a new technique for simultaneous limb lengthening and acute distal femoral angular correction.MethodsA retrospective chart review of patients undergoing a single procedure was conducted. Patients included had a single operation where they underwent distal femur osteotomy stabilized with a plate followed by antegrade nailing with a magnetically controlled intramedullary lengthening nail (PRECICE, Ellipse Technologies, Inc., Irvine, CA, USA) using a trochanteric entry.ResultsSeven femurs from 7 patients were included. The average age at operation was 13.6 years, and the leg length difference was 51 mm (range 30–105 mm). Associated deformities were valgus (4), knee flexion contracture (2), and both valgus and flexion contracture (1). Lengthening achieved was 43 mm (P = 0.0036), with a consolidation index of 27 days/cm and reliability of 0.87 (6/7). The 5 patients with angulation had an improvement of valgus from 12 to 4° (P = 0.006) and of the mechanical axis deviation from 34 to 3 mm (P = 0.0001). The range of motion also improved in the 3 patients with contractures. Preoperative gait disturbance, hip and knee pain, and functional scoliosis resolved after the limb deformities were corrected.ConclusionCombining a magnetic internal lengthening nail with a second distal osteotomy stabilized with a plate can successfully correct limb length and distal femur deformity acutely without altering the expected result of each procedure.

Retrograde Femur Technique for Motorized Internal Limb Lengthening

Deformities of the femur that combine deviations of axis and torsion with length discrepancies are seen quite often. Nevertheless, the surgical treatment can be demanding, especially if fully implantable lengthening nails are used for simultaneous lengthening and deformity correction. The technique of retrograde insertion of a lengthening nail into the femur offers a wider range for correction and allows the treatment of even complex deformities with a single-step procedure. The key to successful application of the technique is meticulous preoperative analysis and planning. The surgical procedure should follow a standardized protocol to avoid pitfalls. A complete overview of the technique of retrograde insertion of lengthening nails into the femur is given.

Low-intensity pulsed ultrasound enhances callus consolidation in distraction osteogenesis of the tibia by the technique of lengthening over the nail procedure

BackgroundLow-intensity pulsed ultrasound (LIPUS) has been widely accepted in promoting the fracture healing process. However, there have been limited clinical trials focused on the efficacy of LIPUS during distraction osteogenesis (DO) by the technique of lengthening over the nail procedure. The purpose of the current study was to evaluate the efficacy of LIPUS during DO.MethodsWe retrospectively evaluated 30 patients (60 segments) who underwent simultaneous bilateral tibial lengthening over the nail. The patients were grouped into the LIPUS group and the control group based on LIPUS stimulation. The two patient groups were compared for demographic data (sex, age at operation, preoperative height, BMI, and smoking history), qualitative assessments of the callus (callus shape and type), external fixation index, and four cortical healing indexes.ResultsFifteen patients (30 segments) were classified as the LIPUS group, and another 15 patients (30 segments) were classified as the control group. No significant differences were found in the assessed demographic data between the groups. LIPUS stimulated a more cylindrical, more homogenous, and denser type of callus formation at the end of the distraction phase. The two groups exhibited equivalent outcomes in terms of external fixation index (p = 0.579). However, significant differences were found in healing indexes of the anterior and medial cortices (p < 0.001 and p = 0.002, respectively). The healing indexes of those cortices in the LIPUS group (mean of 36.6 days/cm and 32.5 days/cm, respectively) reflected their significantly faster healing compared to the control group (mean HI of 57.5 days/cm and 44.2 days/cm, respectively). There were no LIPUS-related complications.ConclusionsLIPUS is a noninvasive and effective adjuvant therapy to enhance callus maturation during DO. It enhances callus consolidation and may have a positive effect on the appropriate callus shape and type.

Osteotomies for deformity correction on the pediatric knee

Fractures in childhood can result in malalignment and/or leg shortening due to insufficient reduction, malunion or injury to the growth plate. Different types of posttraumatic deformities around the knee as well as the diagnostic approach and correction are discussed. While deformities without shortening can often be corrected during surgery with internal fixation, limb shortening with or without malalignment has to be treated with external fixation or internal lengthening nails. Modern six-axis external fixators enable simultaneous lengthening and axial correction in all planes in patients from childhood onwards. Acorrection using lengthening nails is possible at the end of growth or if the physis has already been closed by trauma. Precise analysis of the deformity and leg length discrepancy is necessary to select the best point in time and the right surgical procedure and hardware for correction.

Ankle Arthrodesis with Simultaneous Lengthening of the Lower Limb Using the Ilizarov Fixator.

Patients with advanced ankle arthrosis or joint deformities and co-existing lower limb shortening present a complex therapeutic problem. This paper presents the Ilizarov treatment as a comprehensive method of simultaneous ankle arthrodesis and equalisation of lower limb length in 18 patients. Eighteen patients with arthrosis, deformities or other conditions of the ankle joint and ipsila-teral lower limb shortening were treated with the Ilizarov method. The patients were assessed with the Foot and Ankle Outcomes Questionnaire before the treatment and one year after Ilizarov Fixator removal. The Ilizarov Fixator allows early weight-bearing of the operated limb, which is undoubtedly convenient for the patient. The mean treatment duration was 8.2 months (range 4-18 months). Lower limb lengthening was 4.1 cm on ave-rage (range 2.5-8.5 cm). Bone union was achieved in all cases. Radiological and clinical outcomes were satisfactory in all 18 cases. Prolonged regenerate calcification was recorded in 1 patient. Ten patients developed soft tissue pin-tract infec-tions and in 1 patient the Kirschner wire broke. According to the Foot and Ankle Outcomes Questionnaire, patients achiev-ed a notable improvement in daily functioning and quality of life. 1. The outcomes of a comprehensive treatment con-sisting of ankle arthrodesis and lower-leg leng-then-ing using the Ilizarov method confirm its effec-tiveness. 2. The Ilizarov Fixator allows early weight-bearing of the operated limb and evaluation at all treat-ment stages, creating an optimal biological envi-ron-ment for bone healing. 3. The patient recovers functionally to allow satis-fac-tory and pain-free functioning as well as re-sum-ption of daily responsibilities. The low inci-den-ce of complications adds to the attractiveness of the method.

Simultaneous Radial Lengthening and Ulnar Shortening for a Delayed Presentation of Radius Distal Physeal Arrest: A Case Report

Simultaneous Radial Lengthening and Ulnar Shortening for a Delayed Presentation of Radius Distal Physeal Arrest: A Case Report

Congenital tibial pseudarthrosis, changes in treatment protocol.

Ten children with congenital pseudarthrosis of the tibia were treated with resection of pathologic bone, bone grafting, intramedullary rodding, compression with circular frame, simultaneous proximal tibia lengthening, and bone morphologic proteins. Thirteen operations were performed to achieve union. Four patients underwent simultaneous lengthening and four patients received recombinant human bone morphologic protein. Six children required complementary operations for residual ankle and knee valgus, and shortening. Union of the pseudarthrosis was achieved in all cases with lengthening up to 5 cm. This protocol is effective in achieving union of congenital pseudarthrosis of tibia; attention should be paid to the ankle joint to achieve functionality of the limb.

Simultaneous femoral bifocal non-union compression and lengthening over an intramedullary nail. A novel technique and case report

A first report of simultaneous femoral lengthening with concomitant non-union compression over a previously implanted intramedullary nail is described. A 38 year old male sustained a femoral segmental fracture and developed a persisting atrophic femoral non-union with significant femoral shortening. Combined simultaneous lengthening to correct limb discrepancy with compression of the established non-union with an intramedullary nail in situ was performed using circular external fixation. Successful bifocal non-union compression and femoral lengthening over a nail to address sequelae of a fracture is here described for the first time.

Simultaneous bilateral lengthening of femora and tibiae in achondroplastic patients.

The aim of this study was to analyze the results and complications of simultaneous bilateral femoral and tibial lengthening in achondroplastic patients. The study included the 44 femora and 44 tibiae of 22 achondroplastic patients (16 females, 6 males; mean age: 6.36 years, range: 3 to 11 years) that underwent simultaneous lengthening. Orthofix LRS monolateral fixators were used for femoral lengthening and either Ilizarov-type or hexapod-type circular external fixators for tibial lengthening. Tenotomies of the hip flexors and the Achilles tendon were performed to prevent injury to the growth plates and to prevent joint contractures. Results and complications were evaluated according to Paley's scoring and complication systems. Average follow-up time was 35 (range: 26 to 76) months. The femora were lengthened by an average of 7.07 cm (46.1%), and the tibiae by an average of 6.64 cm (52.9%). Patients gained an average of 16.9 cm in height, including physiological growth. The mean bone-healing index (BHI) was 31.2 days/cm for the femora (range: 17.4 to 43.3 days/cm) and 34.3 days/cm for the tibiae (range: 19.5 to 60.0 days/cm). Complications included 3 delayed maturations, 3 pin track infections, 5 transient fibular paralyses, 5 regenerate fractures, 1 late varus deformity, 1 knee contracture and 1 knee contracture secondary to knee dislocation. Functional scores were excellent in 78 segments, good in 8, fair in 1 and poor in one. There was no growth inhibition related to the lengthening. Bilateral simultaneous lengthening of the femora and tibiae in achondroplastic patients provided a reduction in total treatment and external fixation time, with a low rate of complications.

Femoral lengthening by combined technique in melorheostosis: a case report

Melorheostosis is a rare mesenchymal bone dysplasia characterized by a radiographic pattern of flowing hyperostosis along the cortex with sclerotomal distribution [1]. This condition is typically characterized by cortical hyperostosis and pain in the involved extremity, but can also be associated with soft tissue masses and limb discrepancies and deformities that may be additional sources of disability for those affected by this disease [2–4]. Characteristic radiographic findings can aid in establishing an accurate diagnosis [1, 5]. Cases of progressing and/or significant stiffness with limitations of motion, leg-length discrepancy, and limb deformity provide indications for operative treatment [6, 7]. Because of a low incidence of the disease, there are no universal recommendations for operative treatment of orthopedic complications of melorheostosis and the postoperative period. Thus, a surgeon faces the necessity of intervention with insufficient personal experience and lack of published results. We present a case of operative treatment of an 11-year-old boy affected with melorheostosis, who underwent a simultaneous lengthening and deformity correction of the left lower limb with Ilizarov frame in combination with intramedullary nailing.

Domain evolution processes during poling of a near-morphotropic Pb(Zr, Ti)O3 ceramic

Domain wall motion during the poling of near-morphotropic Pb(Zr,Ti)O3 PZT was observed using Piezoresponse Force Microscopy (PFM). Poling was conducted on bulk polycrystalline PZT in a series of steps, interrupted by vertical PFM scans, which were used to identify the domain evolution processes. The mechanisms of evolution in complex domain patterns such as herringbone and checkerboard structures are revealed. Of interest, in the case of a herringbone pattern consisting of two sets of lamellae angled to each other, one set of lamellae expands and is observed to overwrite the other, transforming the herringbone structure into a single lamination. Also, lengthening without broadening, and simultaneous lengthening and broadening of lamellar domain bands in checkerboard structures are observed. The observations show that 180° and non-180° domain switching can occur simultaneously in complex domain patterns. Methods are developed for identifying the polarization directions of the individual domains in near-morphotropic PZT. The methods combine a knowledge of the compatible domain configurations with crystallographic data from electron backscatter diffraction and PFM data. The resulting map of polarization directions enables clear identification of the polarization switching mechanisms.

The Abbé flap in cleft lip and palate repair

The Abbé flap is a procedure where the volume of the upper lip is increased at the expense of the lower lip. This study reviewed the Abbé flaps done at Skåne University Hospital during the years 1991–2006 and identified 14 patients. Data was collected from medical records. Eleven patients were deemed fit for interviews and were called to the hospital by standard mail. Six patients responded and were interviewed, examined, and photographed. One patient was interviewed over the telephone. Median age at surgery was 14 years (range = 6–22). The operation time was 152 minutes (range = 90–215). The Abbé flap was divided after 12 days (range = 11–16). All 14 flaps survived and no complications were noted. Secondary corrections were done in nine patients. Three patients experienced having their lips sutured together as difficult, and four patients described this period as easy. All patients described their lips as having better appearance after the operation and, in three of four cases, where a simultaneous columella lengthening was done, the patients described their noses as having better appearance. The scar on the lower lip was negative but also a prerequisite for the operation. All seven patients said the operation was worth all the effort and would recommend it to patients in similar situations. This data supports that the Abbé flap is a safe technique that effectively improves the appearance of the upper lip and satisfies the cleft lip and palate patients.

Knee arthrodesis with lengthening: Experience of using Ilizarov techniques to salvage large asymmetric defects following infected peri-articular fractures

We present four patients with large bone defects due to infected internal fixation of knee condylar fractures. All were treated by debridement of bone and soft tissue and stabilisation with flap closure if required, followed by bone transport arthrodesis of the knee with simultaneous lengthening. Four patients (three male and one female), mean age 46.5 years (37-57 years), with posttraumatic osteomyelitis at the knee (three proximal tibia and one distal femur) were treated by debridement of infected tissue and removal of internal fixation. Substantial condylar bone defects resulted on the affected side of the knee joint (6-10 cm) with loss of the extensor mechanism in all tibial cases. Two patients required muscle flaps after debridement. All patients received intravenous antibiotics for at least 6 weeks. Bone transport with a circular frame was used to achieve an arthrodesis whilst simultaneously restoring a functional limb length. In three cases a 'peg in socket' docking technique was fashioned to assist stability and subsequent consolidation of the arthrodesis. Arthrodesis of the knee, free of recurrent infection, was successfully achieved in all cases. None has since required further surgery. Debridement to union took an average of 25 months (19-31 months). The median number of interventions undertaken was 9 (8-12). Two patients developed deep vein thrombosis (DVT), one complicated by PE, which delayed treatment. Two required surgical correction of pre-existent equinus contracture using frames. The median limb length discrepancy (LLD) at the end of treatment was 3 cm (3-4 cm). None has required subsequent amputation. Bone loss and infection both reduce the success rate of any arthrodesis. However, by optimising the host environment with eradication of infection by radical debridement, soft-tissue flaps when necessary and bone transport techniques to close the defect, one can achieve arthrodesis and salvage a useful limb. The residual LLD can result from not accounting for later impaction at peg and socket sites, which had the effect of increasing LLD beyond the desirable amount. We therefore recommend continuing the lengthening for an additional 1-2 cm to allow for this.

PHOTON-INDUCED FORMATION OF MOLECULAR HYDROGEN FROM A NEUTRAL POLYCYCLIC AROMATIC HYDROCARBON: 9,10-DIHYDROANTHRACENE

Experimental results from infrared spectroscopy and mass spectrometry provide compelling evidence that UV irradiation of the neutral polycyclic aromatic hydrocarbon (PAH) 9,10-dihydroanthracene (DHA), trapped in solid argon (12 K), results in efficient (i.e., 90% yield) conversion to anthracene and molecular hydrogen. A number of dissociation pathways involving single or double hydrogen loss are investigated computationally. Among these, two mechanisms are most credible for a one-photon dissociation process involving UV photons <5.5 eV. For the lowest-energy pathway (2.3 eV), a simultaneous lengthening of the C-H bonds of H9 and H10 gives rise to an anthracene-H2 complex. A higher-energy mechanism (3.4 eV) involves an initial lengthening of the H9 C-H bond, followed by this hydrogen grabbing H10, and forming H2. The high yield of this photolysis reaction suggests that similar reactions may take place for other neutral PAHs, with implications for the formation of molecular hydrogen in regions of low UV exposure, such as in dark clouds.

New treatment for peripheral nerve defects: Reconstruction of a 2 cm, monkey median nerve gap by direct lengthening of both nerve stumps

We have developed a new treatment for peripheral nerve defects: nerve-lengthening method, and confirmed the efficacy and safety of our method using cynomolgus monkeys. A 20-mm defect in the median nerve of monkey's forearms was repaired through the simultaneous lengthening of both nerve stumps with original nerve-lengthening device. To evaluate nerve regeneration after neurorrhaphy, electrophysiological, histological, and functional recovery were examined and compared to the standard autografting. Nerve conduction velocity, axon maturation, and the result of functional test were superior in the nerve-lengthening method than in the autografting. And there were no adverse events associated with our method. We concluded that this method is practical for clinical application.