Tibial Lengthening Research Articles

Evaluation of Functional and Biomechanical Properties of Bone Regenerates

Functional tests with incrementing axial load on the affected limb were performed in patients with humerus, tibia and fibula fractures, or undergoing tibial bone lengthening using the Ilizarov apparatus (n = 75). It was found that oossification was associated with a decrease in the blood flow velocity in the arteries of the bone regenerate. In the humerus, the exercise tolerance was two to three times lower, while the micromotion rate of bone fragments and the blood flow velocity were higher. The micromotion rate and the blood flow velocity decreased by the end of the fixation period, since they were no longer affected by the incrementing load.

Sonographic evaluation of distraction osteogenesis in patients undergoing lengthening of tibia for increase in stature

Context: Limb lengthening demands constant monitoring of the regenerate bone by frequent radiological examinations. Aims: The aim of the study was to explore if sonography can be used in place of radiography for monitoring distraction osteogenesis. Settings and Design: This study was a prospective and observational study. Subjects and Methods: Thirty-five consecutive patients with a mean age of 24, where tibia was monofocally lengthened by mean of 5.5 cm ± 0.5 cm were included in the study. Along with all radiological assessments (every 2 weeks during Distraction Phase [DP] and 4 weeks during Maturation Phase [MP]), concurrent sonographic assessment was done and findings compared. Statistical Analysis Used: Descriptive methods. Results: Reparative granulation tissue in the distraction gap and endosteal reaction at both ends were visualized sonographically at 2 weeks before any radiological evidence of regeneration. The echolucent gap increased as distraction progressed with the internal hyperechoic signals getting organized to linear structures at 4 weeks when first radiological evidence was noted. This echopositive portion of the regenerate bone narrowed down by 6−8 weeks when radiographs showed bony trabeculae, more so in MP. By 14−16 weeks of MP, there was a significant reduction of echopositive zone, where more of regenerate got converted to hyperechogenic cortical bone. Sonography was poor in measuring distraction gap and assessing mechanical axis alignment. Sonographic findings correlated well with the findings of accelerated and poor regeneration on radiographs during DP and aided modification of distraction. Conclusions: Sonography is a valuable tool in DP and first half of MP and many radiographic examinations during these phases may be replaced by sonography. Judicious and combined application of sonography and radiography must be explored for superior characterization and monitoring during limb lengthening, with lesser radiation exposure.

Повторное удлинение голени как этап реконструкции ОДС пациентов с ахондроплазией

Objective To show that some achondroplasia cases of surgical locomotor reconstruction require repeated tibial lengthening to achieve optimal anthropometric parameters and review dynamics in reparative osteogenesis during repeated tibial lengthening using optical densitometry. Material and methods A group of patients who underwent double tibial lengthening included 25 achondroplasia and hypochondroplasia patients who underwent treatment at the Russian Ilizarov Scientific Centre “Restorative Traumatology and Orthopaedics” from 2000 to 2013. Results Review of dynamics in reparative osteogenesis revealed no specific course of the procedure. Conclusions Medical, ergonomic and esthetic aspects of achondroplasia treatment can partially be addressed by approaching anthropometric parameters to the biomechanical, ergonomic and esthetic standards through repeated lengthening of lower limb segments.

Оценка численности хондроцитов в суставном хряще при дистракционном остеосинтезе голени в комбинации с накостной пластиной

Introduction The number of chondrocytes in the articular cartilage of the femoral condyles and talus junction surface in the conditions of distraction osteosynthesis of the tibia with the Ilizarov apparatus combined with plating was estimated. Material and methods Seven dogs underwent tibial lengthening at a daily rate of 1 mm for 4 steps and to 14–16 % of the initial length of the segment with the use of the Ilizarov apparatus and plating. Stages of the study were days 30 and 90 in the fixation phase when only plating was left. Histomorphometry of semi-thin sections of the articular cartilage was carried out with the help of an Opton photomicroscope (Germany), DiaMorf software complex (Russia) and VideoTest-Master morphology program. The proportion of chondrocytes (N ch, %), the proportion of empty lacunae (NN em.lac, %), and isogenic groups (NN is.gr, %) were determined in the total sample volume of 200 lacunae. A control group was articular cartilage of five intact dogs. Results The articular cartilage of both articular surfaces retained the zonal structure. Disorder in the homogeneity of the superficial part of the surface zone and destruction of a part of chondrocytes were noted. In the articular cartilage of the femoral condyles, the Nch value was lower than in the control animals by 5.74 %. NN em.lac was increased 2.3 times while NN is.gr values decreased to 2.06 % in the femoral condyle articular cartilage after 30 days of fixation period with the plate. After 90 days of fixation, the N ch values were lower with respect to the controls by 3.73 %. Low values of NN is.gr (4.3 %) and high values of NN em.lac (27.54 %) were maintained. In the articular cartilage of the talus, N ch was lower than in the control group by 1.98 %; NN em.lac increased 1.5 times and NN is.gr decreased to 4.7 % relative to controls after 30 days of fixation. After 90 days, the value of NN em.lac remained at the same level as in the previous experiment stage. The values of NN is.gr were comparable with the control group. Conclusion The technique of distraction osteosynthesis of the tibia in combination with plating is of low traumatic effect on the adjacent joints. A comparative analysis of quantitative parameters of the articular cartilage revealed that the most vulnerable site was the articular cartilage of the femoral condyles.

Alargamiento óseo tibial mediante fijación externa. Estudio comparativo entre la técnica tradicional y la asistida por clavo intramedular

ObjectiveTo compare outcomes and complications when performing bone lengthening with two different techniques: isolated external fixation versus external fixation combined with intramedullary nail. Material and methodComparative retrospective study of thirty cases of tibial lengthening divided in two symmetrical groups. Cases were matched based on several variables to maximise homogeneity between the groups.Variables used for comparison were external fixation time, external fixation index, rate of consolidation, clinical outcomes, complications and range of joint motion. ResultsMean external fixation time was 2.08 months in the group lengthened with nail while the standard group showed 5.85 months (P<.0001). Mean external fixation index was 0.42 months per centimetre in the nail group compared with 1.15 in the group without nail (P<.0001). There were no significant differences in the rate of consolidation (1.23 months per centimetre against 1.15) or in terms of clinical outcomes. We found differences in the rate of complications (1.2 per patient to 2.6) in favour of the technique with nail. There were no differences in the range of motion of ankle joint. Discussion and conclusionsLengthening over an intramedullary nail is more effective than using external fixation alone for tibial lengthening with regard to time of external fixation, index of external fixation and complication rate. We found no advantages in terms of consolidation and joint mobility.

Final adult height in long-term growth hormone-treated achondroplasia patients

The objective of this study was to evaluate the gain in final height of achondroplasia (ACH) patients with long-term growth hormone (GH) treatment. We analyzed medical data of 22 adult patients (8 males and 14 females) treated with GH at a dose of 0.05 mg/kg/day. Optionally, tibial lengthening (TL) was performed with the Ilizalov method in 15 patients and TL as well as femoral lengthening (FL) in 6 patients. Concomitant gonadal suppression therapy with buserelin acetate was applied in 13 patients. The mean treatment periods with GH were 10.7 ± 4.0 and 9.3 ± 2.5 years for males and females, respectively. GH treatment augmented the final height +0.60 ± 0.52 SD (+3.5 cm) and +0.51 ± 1.29 SD (+2.8 cm) in males and females compared to non-treated ACH patients, respectively. Final height of ACH patients that underwent GH and TL increased +1.72 ± 0.72 SD (+10.0 cm) and +1.95 ± 1.34 SD (+9.8 cm) in males and females, respectively. GH, TL, and FL increased their final height +2.97 SD (+17.2 cm) and +3.41 ± 1.63 SD (+17.3 cm) in males and females, respectively. Gonadal suppression therapy had no impact on final height.Conclusions: Long-term GH treatment contributes to 2.6 and 2.1% of final adult height in male and female ACH patients, respectively.

Tibio-talo-calcaneal fusion after limb salvage procedures—A retrospective study

BackgroundThe treatment of limb threatening trauma on the distal tibia or hindfoot often results in posttraumatic osteoarthritis requiring tibiotalocalcaneal (TTC) arthrodesis. The purpose of this study was to present a case series of patients undergoing various techniques of joint fusion after bone reconstruction and deformity correction as a salvage procedure. The study should help trauma surgeons making decisions in limb salvage and deformity correction in complex lower leg and foot injuries by presenting options and treatment strategies. Patients and methodsEight patients (4 male, 4 female) after TTC arthrodesis as a definitive procedure after polytrauma or monotrauma involving the distal tibia or hindfoot were the subject of this retrospective analysis. We included patients treated by external ring fixation (1 case), external fixation+wires (1 case), external fixation+screws (1 case) and intramedullary nailing (1 ante- and 5 retrograde; 1 bilateral, 4 unilateral). Initial trauma included open fractures, subtotal foot amputations and closed fractures with failed osteosynthesis and failed ankle joint replacement. Bone defects were treated with callus distraction or segment transport in 5 cases. Various angles were measured to assess foot deformities in the lateral radiographic view and clinical results were presented. ResultsIndependent, pain-free mobilisation with full weight bearing was achieved in all 8 patients. In terms of subjective outcome, all patients reported a highly satisfying result. Complete consolidation at the fusion site was achieved in 8 out of 9 cases with a high rate of adjacent joint arthritis. Angles measures in the lateral radiographs showed values typical for a pes cavus tendency. ConclusionTibio-talo-calcaneal (TTC) arthrodesis is a viable treatment option for severe post traumatic arthritis and deformity of the ankle and subtalar joint. Despite bad bone quality retrograde intramedullary nailing does provide acceptable results providing stability, low invasiveness and low infection rate. Simultaneous TTC-fusion and tibial lengthening using the Ilizarov ring fixator may be necessary when the surgeon is confronted with large bone defects – often followed by a nailing after lengthening procedure. This study shows that limb preservation after limb threatening trauma with hindfoot injury and multiple fractures of the lower extremity is recommenced as the method of choice with reasonable clinical results.Level of Evidence: IV, Case series

Physeal and Subphyseal Distraction Osteogenesis in Atrophic-type Congenital Pseudarthrosis of the Tibia: Efficacy and Safety.

To examine the efficacy, safety, and clinical outcomes of distraction osteogenesis through the physis (PDO) or through subphyseal osteotomy (SPDO) in patients with atrophic-type congenital pseudarthrosis of tibia with proximal tibial dysplasia. To validate the efficacy and safety of PDO and SPDO, radiographic and clinical parameters were compared between 5 patients who underwent proximal tibial metaphyseal or metadiaphyseal lengthening as a control (group 1) and 7 patients who underwent PDO or SPDO (group 2). Postoperative complication was also compared between the groups. A significant difference in terms of healing index (group 1, 83.3±24.7 d/cm; group 2, 35.0±11.1 d/cm; P=0.001) and percentage increase (11.0%±3.7% vs. 23.1%±10.5%, P=0.034) was observed between the 2 groups. According to the Paley classification, group 1 included 1 "problems" case and 3 "obstacles" cases, whereas group 2 included 2 "problems" cases and 1 "obstacles" case. According to the Lascombes classification, group 1 included 2 grade IIIb cases and 3 grade IV cases, whereas group 2 included 6 grade I cases and 1 grade IIa case. Severe complications were significantly higher in group 1 compared with the group 2 (P=0.007). This study demonstrated that PDO or SPDO can be effectively and safely performed for tibial lengthening in atrophic-type congenital pseudarthrosis of tibia patients with proximal tibial dysplasia. Level III.

Limb lengthening and deformity correction of congenital and acquired deformities in children using the Taylor Spatial Frame

Background and purpose — Hexapod ring fixators such as the Taylor Spatial Frame (TSF) have shown good outcomes. However, there have only been a few studies comparing the use of TSF with various etiologies of the deformity. We compared the use of TSF in congenital and acquired deformities in children.Patients and methods — We reviewed 213 lower extremity reconstructive procedures with the TSF in 192 patients who were operated between October 2000 and October 2015. 128 procedures (67 proximal tibiae, 51 distal femora, and 10 distal tibiae) in 117 children (median age 14 (4–18) years; 59 girls) fulfilled the inclusion criteria. 89 procedures were done in children with congenital deformities (group C) and 39 were done in children with acquired deformities (group A). Outcome parameters were lengthening and alignment achieved, lengthening index, complications, and analysis of residual deformity in a subgroup of patients.Results — Mean lengthening achieved was 3.9 (1.0–7.0) cm in group C and 3.7 (1.0–8.0) cm in group A (p = 0.5). Deformity parameters were corrected to satisfaction in all but 3 patients, who needed further surgery for complete deformity correction. However, minor residual deformity was common in one-third of the patients. The mean lengthening index was 2.2 (0.8–10) months/cm in group C and 2.0 (0.8–6) months/cm in group A (p = 0.7). Isolated analysis of all tibial and femoral lengthenings showed similar lengthening indices between groups. Complication rates and the need for secondary surgery were much greater in the group with congenital deformities.Interpretation — The TSF is an excellent tool for the correction of complex deformities in children. There were similar lengthening indices in the 2 groups. However, congenital deformities showed a high rate of complications, and should therefore be addressed with care.

Guidelines for safe bilateral tibial lengthening for stature

Context: Limb lengthening has its own share of problems, obstacles, and complications, which is of great concern when used for a cosmetic indication. Aims: This study explores safe limits for cosmetic tibial lengthening and examines how age of the patient and length gained influences osteogenesis and complications. Settings and Design: This was a retrospective analytical study. Subjects and Methods: We reviewed 70 consecutive cases (140 segments) of monofocal tibial cosmetic lengthening with minimum of 1-year follow-up operated between 2006 and 2010. Statistical Analysis Used: We correlated patient's age and percentage by which bone was lengthened with external fixator index (EFI) and occurrence of obstacles and complications and did receiver operator characteristic (ROC) curve analysis to determine the safe limit. Results: Mean age of patients was 27 (16–52) years. Mean tibial lengthening was by 16.5% (4.1–27.9) of the preoperative length. Sixty segments faced 76 difficulties comprising 16 problems, 47 obstacles, and 13 complications. Patient's age positively correlated with EFI, but did not correlate with the incidence of obstacles and complications. Percentage by which bone was lengthened negatively correlated with EFI and positively correlated with incidence of obstacles and complications. ROC curve analyses (with optimum balance of sensitivity and specificity) revealed lengthening by more than 18.1% and 16.4% to be significantly associated with the occurrence of complication and more than one obstacle, respectively. Conclusions: In cosmetic tibial lengthening, increasing age increases the duration of external fixation and increased lengthening increases obstacles and complications. Great caution must be exercised in cosmetic tibial lengthening beyond 16%.

Combined tibial lengthening and ankle arthrodesis for patients with certain type of sequelae of poliomyelitis.

Following far advancement of modern medicine and technology, functional disability in a certain type of sequelae of poliomyelitis may be effectively improved. Eight consecutive adult patients with unilateral sequelae of poliomyelitis were treated. These patients had shortened lower extremity of an average of 4.8 cm (range, 4.0-5.5 cm) in the lesion side. Muscle power of the ipsilateral knee was nearly intact (grade 4 or 5) but the ankle extension was completely flaccid. The tibia was osteotomized and lengthened with external fixation. Consequently, all external fixators were converted to plates supplemented with autogenous corticocancellous bone graft and bone graft substitute. Ankle arthrodesis was performed concomitantly. Seven patients were followed up for an average of 3.7 years (range, 2.2-5.4 years). All seven lengthened sites healed with an average union time of 3.9 months (range, 3.5-4.5 months) after plating. One ankle infection occurred. Gait function significantly improved by modified Mazur scoring evaluation ( p = 0.02). At the latest follow-up, all patients had a minimal or unnoticed limp in level walking. The described combined techniques may be an excellent alternate for treating selected patients with sequelae of poliomyelitis. The procedure is not complex but the efficiency is extremely prominent.

Экспериментальное обоснование комбинированного дистракционного остеосинтеза накостной пластиной и аппаратом Илизарова

Introduction The decrease in the external osteosynthesis index during limb lengthening is a relevant problem to solve by the current orthopaedics, especially in regard to children. Intramedullary rods in pediatric orthopaedics are contraindicated due to open growth plates. The use of intramedullary wires reduces the period with the fixator on the patient’s limb but the index of osteosynthesis remains rather high. Purpose To analyze the results of the combined use of the Ilizarov fixator and an internal plate of an original design for experimental tibial lengthening. Material and Methods Leg lengthening was performed in 6 experimental dogs using the Ilizarov fixator and plating. The procedure of segmental lengthening by 14-16 % from the initial length was performed in the manual mode with the rate of 1 mm per day produced with 4 steps. Results The planned amount of lengthening was achieved in all the animals. The use of plating enabled to remove the fixator on the day of distraction completion. The index of external osteosynthesis was 12.7±0.7 day/cm. The regenerated bone was of normoplastic type. It acquired a homogenous structure after 30 days of fixation in the majority of cases. As for the complications, the resorption round one of the screws that fixed the plate was observed along with soft tissue inflammation but it did not affect the experiment results. Conclusion The combined use of plating and the Ilizarov fixator decreased the external osteosynthesis index and prevented the complications related to regenerated bone fracture or deformity after the fixator removal.

Outcomes following femoral lengthening: An initial comparison of the Precice intramedullary lengthening nail and the LRS external fixator monorail system.

Patients undergoing femoral lengthening by external fixation tolerate treatment less well when compared to tibial lengthening. Lengthening of the femur with an intramedullary device may have advantages. We reviewed all cases of simple femoral lengthening performed at our unit from 2009 to 2014. Cases of nonunions, concurrent deformities, congenital limb deficiencies and lengthening with an unstable hip were excluded, leaving 33 cases (in 22 patients; 11patients had bilateral procedures) for review. Healing index, implant tolerance and complications were compared. In 20 cases (15 patients) the Precice lengthening nail was used and in 13 cases (sevenpatients) the LRS external fixator system. The desired length was achieved in all cases in the Precice group and in 12 of 13 cases in the LRS group. The mean healing index was 31.3days/cm in the Precice and 47.1 days/cm in the LRS group (p < 0.001). This was associated with an earlier ability to bear full weight without aids in the Precice group. There were more complications with LRS lengthening, including pin site infections and regenerate deformity. Implant tolerance and the patients' perception of the cosmetic result were better with the Precice treatment. Femoral lengthening with the Precice femoral nail achieved excellent functional results with fewer complications and greater patient satisfaction when compared with the LRS system in our patients. Cite this article: Bone Joint J 2016;98-B:1382-8.

PARACRINE REGULATORS IN DISTRACTION OSTEOGENESIS (pilot study)

Purpose – to evaluate effect of protein extracted from lengthened skeletal muscles on callus formation in dogs after tibia lengthening using Ilizarov method.Materials and methods. The authors studied properties of distraction callus formation in three groups of dogs after tibia lengthening by Ilizarov method. In the first group (n = 10) distraction was achieved at a rate of 1 mm in four stages during 28 days. In the second (n = 4) and third (n = 4) groups distraction was done at a rate of 1.5 mm in 6 stages per day within 20 days. Mean lengthening value in all groups amounted to 14,64±0,67% of the overall segment length. At the 10th day of distraction the authors introduced to animals of the second group into anterior tibial and gastrocnemius muscles of the lengthened segment at callus level the extract of sarcoplasmic proteins in amount of 1.5ml based on 1 mg of lyophilizate per 1 kg of body weight (protein concentration in injectate amounted to 30±2 gr/l). Animals in the third group received natural saline solution in the same manner. Extract consisted of lyophilized sarcoplasmic proteins harvested from anterior tibial muscle of animal at 14th day of lengthening by Ilizarov method (rate of 1 mm per day in 4 stages). Extraction was performed according to patented method (Russian Federation patent for invention №2476234) by consecutive muscle proteins sedimentation in KCl solutions of varied ionic strength. The lyophilizate was sterilized after obtaining and dissolved in normal saline solution prior to introduction.Results. Radiographic signs of anatomically solid callus in the first group were observed in the average at 33±1 day of fixation; in the second group – at 24±2 day; in the third group – at 39±3. Difference in mean values of fixation in animals of second group as compared to first and third groups was significant (р = 0,04). After extract introduction the animals of the second group demonstrated a greater growth of γ-globulins and α2-globulins fraction volumes.Conclusion. Skeletal muscles of limb segment lengthened by Ilizarov method produce specific factors that impact the process of distraction osteogenesis.

CLINICAL APPLICATION OF AXIAL LOAD MECHANICAL TESTING IN REMOVING EXTERNAL FIXATOR AFTER TIBIA AND FIBULA FRACTURES SURGERY

To explore the efficacy and safety of the axial load mechanical testing for removing external fixator. Between January 2014 and August 2015, 27 patients with tibia and fibula fractures caused by trauma underwent an external fixation. Of 27 patients, 21 were male and 6 were female with the average age of 45 years (range, 19-63 years), including 7 cases of closed fracture and 20 cases of open fracture. X-ray film results showed spiral unstable fracture in 4 cases and comminuted unstable fracture in 23 cases. All patients underwent an external fixation. Bone nonunion occurred in 3 cases because of infection, and bone nonunion combined with bone defect occurred in 1 case, who received tibial osteotomy lengthening surgery. When X-ray film showed continuity high density callus formation at fracture site, axial load mechanical test was performed. If the axial load ratio of external fixator was less than 10%, the external fixator was removed. At 21-85 weeks after external fixation (mean, 44 weeks), axial load mechanical test was performed. The results showed that the axial load ratio of external fixation was less than 10% in 26 cases, and the external fixator was removed; at 6 weeks after removal of external fixator, the patients could endure full load and return to work, without re-fracture. The axial load ratio was 14% in 1 case at 85 weeks, and the X-ray film result showed that fracture did not completely heal with angular deformity; re-fracture occurred after removing external fixator, and intramedullary fixation was used. External fixator axial load mechanical testing may objectively reveal and quantitatively evaluate fracture healing, so it is safe and reliable to use for guiding the external fixator removal.

Ilizarov tibial lengthening in the skeletally immature patient.

We wished to examine the effectiveness of tibial lengthening using a two ring Ilizarov frame in skeletally immature patients. This is a potentially biomechanically unstable construct which risks the loss of axial control. We retrospectively reviewed a consecutive series of 24 boys and 26 girls, with a mean age of 8.6 years (4 to 14), who underwent 52 tibial lengthening procedures with a mean follow-up of 4.3 years (4.0 to 16.9). Tibial alignment was measured before and after treatment using joint orientation lines from the knee and a calculation of the oblique plane axis. The mean percentage length gain was 20% (13 to 31) with a mean bone-healing index (BHI) of 34 days per centimetre (20 to 54). Age at surgery and location of the osteotomy site showed a strong relationship as the location of the osteotomy migrated more proximally with age. However, no significant correlation was found between BHI and the position of the osteotomy. The coronal and sagittal joint orientation of the lengthened tibias were within the normal range in 67% and 92% of cases, respectively. The oblique plane angulation calculation revealed a statistically significant change pre- to post-operatively in both magnitude (p < 0.05) and direction (p < 0.01), but without clinical consequence. The majority of complications were minor (n = 40 in 27 patients; 1.48 complications per segment lengthened) with no residual disability reported. Two-ring tibial lengthening is effective in maintaining segmental alignment, efficient in callous production and relatively comfortable for the patient with few significant complications. Cite this article: Bone Joint J 2016;98-B:1276-82.

Pediatric clubfoot : Treatment of recurrence

Over the last 10 years the Ponseti method has become established as the gold standard for initial treatment of clubfeet nearly worldwide. Nevertheless, there are considerable fluctuations regarding the authenticity and quality in the application of the Ponseti method. Especially the efforts to ensure and promote compliance with the foot abduction brace and subsequently the recurrence rate show great variation. As a result, we are still faced with a significant number of recurrent or residual clubfeet. In recent years it has been shown in high-volume clinics that even these can almost always be successfully treated with recasting and with minor interventions, such as anterior tibial tendon transfer and lengthening of the Achilles tendon. More invasive surgical procedures are only very rarely indicated and are reserved for severe recurrence in previously surgically treated and secondary clubfeet.

Limb lengthening in achondroplasia.

Background:Stature lengthening in skeletal dysplasia is a contentious issue. Specific guidelines regarding the age and sequence of surgery, methods and extent of lengthening at each stage are not uniform around the world. Despite the need for multiple surgeries, with their attendant complications, parents demanding stature lengthening are not rare, due to the social bias and psychological effects experienced by these patients. This study describes the outcome and complications of extensive stature lengthening performed at our center.Materials and Methods:Eight achondroplasic and one hypochondroplasic patient underwent bilateral transverse lengthening for tibiae, humeri and femora. Tibia lengthening was carried out using a ring fixator and bifocal corticotomy, while a monolateral pediatric limb reconstruction system with unifocal corticotomy was used for the femur and humerus. Lengthening of each bone segment, height gain, healing index and complications were assessed. Subgroup analysis was carried out to assess the effect of age and bone segment on the healing index.Results:Nine patients aged five to 25 years (mean age 10.2 years) underwent limb lengthening procedures for 18 tibiae, 10 femora and 8 humeri. Four patients underwent bilateral lengthening of all three segments. The mean length gain for the tibia, femur and humerus was 15.4 cm (100.7%), 9.9 cm (52.8%) and 9.6 cm (77.9%), respectively. Healing index was 25.7, 25.6 and 20.6 days/cm, respectively, for the tibia, femur and humerus. An average of 33.3% height gain was attained. Lengthening of both tibia and femur added to projected height achieved as the 3rd percentile of standard height in three out of four patients. In all, 33 complications were encountered (0.9 complications per segment). Healing index was not affected by age or bone segment.Conclusion:Extensive limb lengthening (more than 50% over initial length) carries significant risk and should be undertaken only after due consideration.

Application of "4-in-1 osteosynthesis" in the combined surgical technique for the treatment of congenital pseudarthrosis of tibia in children

Objective To investigate the indications, operative technique, and outcomes of combined surgical technique and 4-in-1 osteosynthesis for congenital pseudarthrosis of the tibia (CPT). Methods A retrospective study was performed on 12 patients (10 boys and 2 girls) with CPT and fibular pseudarthrosis who were treated with combined surgical technique and 4-in-1 osteosynthesis from May 2012 to September 2014. The average age during surgery was 4.4 years (1.2-10.1 years). Five patients were under the age of 3 years old. Seven patients had no previous surgery, but 5 patients underwent between one and four unsuccessful procedures in other hospital. Of the 12 patients, two had proximal tibia dysplasia, seven cases exhibited neurofibromatosis type Ⅰ. 10 cases showed limb length discrepancy (LLD) with an average limb length of 4.5 cm (2-11 cm). Combined surgical technique and 4-in-1 osteosynthesis included intramedullary rod insertion, installation of Ilizarov's fixator, tibio-fibular cross union, and wrapping autogenic iliac bone graft. Seven patients were planned by proximal tibial lengthening. The incidence of refracture, ankle valgus, tibial valgus and LLD in patients were investigated with an average followup time of 28.5 months (14.3-45.7 months). Results Seven patients were treat by tibia lengthen at the same time. The average operating time was 4 h (3.5-4.5 h); the average blood loss was 113 ml (60 -150 ml). All patients achieved primary union, and the average primary union time was 4.1 months (3.3-4.8 months). Seven (58%) cases showed LLD with an average limb length of 2.9 cm (0.8-5.0 cm), four patients were treat by tibia lengthen. Two (17%) cases exhibited tibial valgus; one case with the tibial valgus deformity of 13°; one case with the tibial valgus deformity of 15°. The cross sectional area of bone graft was enlarged to 2.3 times (1.5-2.8 times) of the tibia shaft. No case showed refracture and ankle valgus during the follow-up periods. Eight cases restored movement of ankle joint with an average dorsiflexion 23° (20°-30°) and an average plantar flexion 42° (40°-50°), and the function of ankle joint was normal. The ankle joint in other 4 cases were fixed in neutral position. Conclusion Combined surgical technique and 4-in-1 osteosynthesis can provide satisfactory results in short-term follow-up in treating CPT. By the help of this procedure, the early healing rate is high with larger cross-sectional area in fusion joint. However, some complications, such as tibial valgus and unequal leg length, should be considered. Key words: Child; Pseudarthrosis; Tibia; Treatment outcome

Clinical Results and Complications of Lower Limb Lengthening for Fibular Hemimelia: A Report of Eight Cases.

Fibular hemimelia is a rare but the most common congenital long bone deficiency, encompassing a broad range of anomalies from isolated fibular hypoplasia up to substantial femoral and tibial shortening with ankle deformity and foot deficiency. Most cases of fibular hemimelia manifest clinically significant leg length discrepancy (LLD) with time that requires adequate correction by bone lengthening for stable walking. Bone lengthening procedures, especially those for pathological bones, are sometimes associated with severe complications, such as delayed consolidation, fractures, and deformities of the lengthened bones, leading to prolonged healing time and residual LLD at skeletal maturity. The purpose of this study was to review our clinical results of lower limb lengthening for fibular hemimelia.This study included 8 Japanese patients who diagnosed with fibular hemimelia from physical and radiological findings characteristic of fibular hemimelia and underwent single or staged femoral and/or tibial lengthening during growth or after skeletal maturity. LLD, state of the lengthened callus, and bone alignment were evaluated with full-length radiographs of the lower limb. Previous interventions, associated congenital anomalies, regenerate fractures were recorded with reference to medical charts and confirmed on appropriate radiographs. Successful lengthening was defined as the healing index <50 days/cm without regenerate fractures.A significant difference was observed in age at surgery between successful and unsuccessful lengthening. The incidence of regenerate fractures was significantly correlated with callus maturity before frame removal. LLD was corrected within 11 mm, whereas mechanical axis deviated laterally.Particular attention should be paid to the status of callus maturation and the mechanical axis deviation during the treatment period in fibular hemimelia.