Tibial lengthening over nails in children using modified Ender nails: preliminary results of a new treatment

Femoral lengthening using limb reconstruction system augmented with only one antegrade flexible nail in children: early results

Several techniques have been described for decreasing the duration of external fixator use, augmenting stability, and minimizing complications. The purpose of the present study was to evaluate the clinical results and complications of femoral lengthening procedures using the Limb Reconstruction System (LRS) in combination with a single antegrade flexible intramedullary nail (FIN). Femoral lengthening with LRS and FIN was applied to 14 patients (aged 6-16 years) between 2017 and 2021. The etiology was a congenital femoral deficiency in 12 patients and post-traumatic growth arrest in two. A single nail was inserted antegradely through the trochanteric apophysis in each patient. Radiographs and medical records of the patients were assessed retrospectively. The mean lengthening achieved was 4.8 ± 1.0 cm. The mean duration of external fixation was 181 days (range 139-248 days) and the mean healing index was 39.6 ± 12.1 days/cm. The mean values of mechanical medial proximal tibial angle, mechanical lateral distal tibial angle, mechanical lateral proximal femoral angle, and mechanical lateral distal femoral angle were within the normal range at the last follow-up. Seven of the 14 cases had a regenerate deformity that caused a displacement of more than 2 mm in the mechanical axis deviation, none of them was greater than 10 mm and considered clinically insignificant. Fracture was seen in two limbs with regenerate deformity. This study suggests that LRS in combination with only one FIN may be an effective alternative for femoral lengthening, with acceptable complication rates.

Combined lengthening for acquired leg length discrepancy: Are there advantages of hydroxyapatite-coated intramedullary nails?

INTRODUCTION

The aim of this multicenter prospective study was to analyze the outcomes of bone lengthening by external fixator associated with flexible intramedullary nailing (FIN) in acquired limb length discrepancy (LLD).

HYPOTHESIS

Hydroxyapatite (HA)-coated FIN enables reduced External Fixation Index in limb lengthening for acquired leg length discrepancies in comparison to non-HA-coated FIN.

MATERIAL AND METHODS

This study included 54 patients (mean age, 17.9 years) operated on for femoral or tibial lengthening by combined technique (External fixator with FIN) for acquired length discrepancy. Titanium non-HA-coated FIN (29 cases) or HA-coated FIN (25 cases) were used. The factors that might influence external fixation index, complication occurrence and outcome were analyzed: age, amount of lengthening, nail diameter, HA-coating vs. non-HA-coated nails.

RESULTS

The mean External Fixation Indexes (EFI) of groups compared for non-HA-coated nails vs. HA-coated nails were not significantly different: 26.5 d/cm and 27.2 d/cm in femoral lengthening and 34.9 d/cm and 31.7 d/cm in tibial lengthening. Positive correlation between the "nail diameter/inner distance between cortices at osteotomy site" ratio and EFI in tibial lengthening was revealed (p=0.034). The nail types and the "nail diameter/medullary canal diameter" ratio interact and have significant simultaneous effect on EFI in femoral lengthening (p=0.021).

DISCUSSION

The results of this study revealed no differences with regards to EFI using HA-coated or non-HA-coated titanium FIN in lengthening for acquired leg-length discrepancies. Combined technique allowed reduced EFI and avoided major complications. Both non-HA-nail and HA-coated nail lengthening provided good and excellent outcomes.

LEVEL OF EVIDENCE

III; (controlled trial without randomization) prospective comparative study.

Limb Lengthening for Congenital Deficiencies Using External Fixation Combined With Flexible Intramedullary Nailing: A Multicenter Study

BACKGROUND

Hydroxyapatite (HA) coated flexible intramedullary nailing (FIN) stimulates osteogenic activity. The role of HA-coated intramedullary nails remains unclear in normal bone lengthening. The goal of this study was to quantify the influence of FIN on the External Fixation Index (EFI) in patients with congenital lower limb discrepancy.

METHODS

Patients with femoral deficiency and fibular hemimelia underwent lengthening by the combined technique of external fixation with titanium (Ti) FIN or HA coated FIN and returned for follow-up at least 12 months after frame removal.

RESULTS

Seventy patients (mean age of 12.6 y) were included: 19 monofocal femoral lengthenings, 35 tibial monofocal lengthenings, 16 tibial bifocal lengthenings. The mean EFI's for those treated with and without HA-coated nails were not significantly different. The Conover posthoc analysis did not reveal a significant influence of the type of FIN on EFI in any subgroup. However, 2-way analysis of variance revealed simultaneous effects of nail types and age on the EFI in tibial bifocal lengthening.Significant positive correlation between the ratio "nail diameter/medullary shaft diameter" and EFI in tibial bifocal non-HA-coated FIN lengthening, and a significant positive correlation between age and EFI for femoral non-HA-coated FIN lengthening, tibial monofocal and bifocal HA-coated FIN lengthening were revealed.There were 4 cases of fracture at lengthening site required unscheduled surgery. In the non-HA-coated group, there was a statistically significant negative correlation between nail diameter and fracture occurrence at the lengthening site after frame removal. A ratio of <0.15 likely does not ensure required mechanical stability and support.

CONCLUSIONS

Both Ti-nail and HA-coated nail lengthening provide good and excellent outcomes for femoral and tibial monosegmental lengthening procedures and ensure reduced EFI. In congenital disorders which were not associated with abnormal bone, there are no differences with regard to EFI using HA-coated or non-HA-coated FIN. The ratio of "elastic Ti-nail diameter/medullary canal diameter at narrowest site" <0.15 seems to be associated with higher risk of fracture at the lengthening site after frame removal.

Tibial Lengthening Using a Fixator-Assisted Lengthening Plate: A New Technique

Background

There are many techniques that are used for limb lengthening. Lengthening a limb over a plate is an alternative choice used in children or when using an intramedullary nail is difficult.

Objectives

In this study, we presented a new technique for tibial lengthening using a monolateral external fixator over a lengthening plate.

Materials and Methods

For tibial lengthening, a monolateral external fixator was attached to the composite bone model medially. After a corticotomy was performed, the lengthening plate was placed laterally. Three locking screws were inserted proximally, and two cortical screws were inserted into a lengthening hole that was 1 cm below the osteotomy site. We avoided contact between the screws of the lengthening plate and the pins of the external fixator. During bone lengthening with the monolateral external fixator, the screws at the lengthening hole were able to slide distally with the distal segment of the tibia to allow for tibial elongation. Two locking screws were fixed at the distal locking holes of the plate when the bone elongation was complete. The external fixator was then removed.

Results

The fixator-assisted lengthening plate allowed bone lengthening without malalignment. There were no mechanical problems associated with the external fixator during the lengthening process. Plate osteosynthesis was stable after the fixator was removed. There was no contact between the screws of plate and the Schanz pins of the external fixator under C-arm fluoroscopy.

Conclusions

The fixator-assisted lengthening plate technique helps to maintain the stability and alignment at both sides of an osteotomy during tibial elongation. It allows the early removal of the external fixator immediately after lengthening is completed. This technique can be applied in children with open physes and in patients with a narrow medullary canal who are unsuitable for limb lengthening over an intramedullary nail.

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.

Tibial lengthening over intramedullary nails: A matched case comparison with Ilizarov tibial lengthening

Objectives

The purpose of this study was to compare the results and complications of tibial lengthening over an intramedullary nail with treatment using the traditional Ilizarov method.

Methods

In this matched case study, 16 adult patients underwent 19 tibial lengthening over nails (LON) procedures. For the matched case group, 17 patients who underwent 19 Ilizarov tibial lengthenings were retrospectively matched to the LON group.

Results

The mean external fixation time for the LON group was 2.6 months and for the matched case group was 7.6 months. The mean lengthening amounts for the LON and the matched case groups were 5.2 cm and 4.9 cm, respectively. The radiographic consolidation time in the LON group was 6.6 months and in the matched case group 7.6 months. Using a clinical and radiographic outcome score that was designed for this study, the outcome was determined to be excellent in 17 and good in two patients for the LON group. The outcome was excellent in 14 and good in five patients in the matched case group. The LON group had increased blood loss and increased cost. The LON group had four deep infections; the matched case group did not have any deep infections.

Conclusions

The outcomes in the LON group were comparable with the outcomes in the matched case group. The LON group had a shorter external fixation time but experienced increased blood loss, increased cost, and four cases of deep infection. The advantage of reducing external fixation treatment time may outweigh these disadvantages in patients who have a healthy soft-tissue envelope.

Cite this article: J. E. Herzenberg. Tibial lengthening over intramedullary nails: A matched case comparison with Ilizarov tibial lengthening. Bone Joint Res 2016;5:1–10. doi: 10.1302/2046-3758.51.2000577

Experimental study of progressive tibial lengthening in dogs using the Ilizarov technique. Comparison with and without associated intramedullary K-wires

A delay in the union of bone regenerate in surgical lengthening procedures and the healing index (HI) are major factors in the quality of the results in progressive bone lengthening. Early removal of the external fixator (EF) is associated with a low rate of postoperative complications, including pin track infection, and with better muscle and joint function recovery. Addition of intramedullary wires (IMWs) to the EF led to a 9-49% decrease in the HI depending on the clinical series. We hypothesized that IMWs may accelerate the ossification process of bone regenerate and tested it in this experimental study.

METHODS

Progressive tibial lengthening of 28 mm was obtained in 12 dogs operated with the classical Ilizarov technique (group I) and in 12 dogs operated with the same technique and addition of two IMWs 1.5 mm in diameter (group II). The following criteria were assessed: HI, X-ray measurements, and histological aspect of the bone regenerate and postoperative complications.

RESULTS

The mean HI was 32.3% lower in group II than in group I. The radiological bone union criteria were observed on day 15 of the fixation period in group II versus day 30 in group I. Histology showed that maturation occurred earlier and bone cortices were thicker in group II than group I. Intramedullary ossification was present along the IMW in group II, whereas it was absent in group I. No clinical complications were observed in either group.

DISCUSSION

The presence of the IMWs clearly contributes to stimulation of the ossification processes of the bone regenerate and to acceleration of bone union. IMWs allowed an earlier removal of the external fixator for a 32% time reduction compared to cases without IMWs. In addition, new intramedullary bone formation and presence of IMWs are expected to increase the mechanical resistance of the bone regenerate.

CONCLUSION

Improvement of quantitative and qualitative criteria of bone regenerate in progressive bone lengthening with an EF combined with IMWs was demonstrated in this experimental study.

SIGNIFICANCE

Favorable results encourage the authors to continue using IMWs in addition to the EF in patients treated with long-bone progressive lengthening.

LEVEL OF EVIDENCE

II.

Bilateral tibial lengthening over the nail: our experience of 143 cases

INTRODUCTION

Using lengthening over an intramedullary nail as a technique for cosmetic purposes improves the individuals' quality of life and provides more satisfactory results due to less external fixator period.

METHODS

This study reports a case series of 143 individuals who underwent bilateral tibial lengthening over an intramedullary nail for cosmetic purposes together with the review of parameters related to the surgery and complications. Level of satisfaction was measured with the standard visual analog scale at least 1 year after removal of external fixator.

RESULTS

In this study, mean (SD) age of patients was 26.6 (7.26) years. 85 (59.4%) participants were male and 58 (40.6%) were female. Mean end lengthening of all individuals was 6.65 cm. The mean external fixator period was 93.7 days. Complication rate was 0.74 per segment but it decreased to 0.45 when pin-tract infection was excluded. Complications were categorized based on Paley et al.'s classification as 129 problems, 85 obstacles and no sequelae. Interestingly, 44 (30.8%) individuals had no problem and obstacle.

CONCLUSIONS

Lengthening over an intramedullary nail provides bone formation in equal quality to that obtained by the conventional Ilizarov method, along with lower rate of complications. The large number of individuals involved in our study is a remarkable benefit which could be used as an appropriate sample to compare results for outcomes and complications.

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 Ilizarov's 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.

Lower limb lengthening and deformity correction using the Fitbone motorized nail system in the adolescent patient

Leg lengthening by an external fixation is associated with various difficulties. Pin-tract infections are commonly encountered, and muscle contractures and joint stiffness are additional complications associated with this method. Several researchers explored a purely intramedullary solution for leg lengthening since the 1970s. The purpose of this study was to evaluate the results of 10 adolescent patients who underwent leg lengthening with a motorized intramedullary lengthening device (the Fitbone System). We aimed to evaluate the effectiveness of the Fitbone system in deformity correction and lengthening of the femur and tibia in the pediatric and adolescent patients looking at whether the incidence of complications commonly associated with external fixators could be reduced. We compared our preliminary results with those from other reports, with a focus on leg length achieved and rate of complications. Ten patients were included, nine femoral nails and five tibial nails were implanted. The average lengthening distance was 4.8 cm (range, 2.8-10 cm). In 10 patients, leg lengthening was combined with successful correction of the mechanical axis alignment in three patients. The consolidation index averaged 24 days/cm (range, 20-39 days/cm). The average hospital stay was 8 days. No bone or soft tissue infections were observed. Only one patient had irritation and pain from the antenna system after lengthening and recovered fully after antenna removal. Our results suggest that the difficulties commonly associated with external fixators can be reduced with this method. It also allows good angular correction in patients with mechanical axis deviation. These features combined with a short time of hospitalization make it a promising procedure for limb lengthening in adolescent patients.

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.

DEXA as a predictor of fixator removal in distraction osteogenesis

Premature removal of the fixator after a lengthening procedure can result in gradual bending or acute fracture of the regenerate. We reviewed the records of 26 patients who underwent 28 limb lengthenings between 1997 and 2005 to assess the post lengthening regenerate fracture rate and bone healing index when using dual energy xray absorptiometry (DEXA) to aid in deciding on when to remove the fixator. Sixteen male and 10 female patients with an average age at lengthening of 12.3 years underwent an average lengthening of 5.2 cm (range, 3-9.1 cm). Nineteen femurs and nine tibiae were lengthened. Serial monthly DEXA scans were analyzed for bone mineral density. Bone healing indices and post fixator removal complications were assessed. The fixators were removed once the bone mineral density had plateaued to a less than 10% increase and plain radiographs showed no obvious defects precluding fixator removal. There were no regenerate fractures and only one fracture in the proximal segment of the lengthened bone after apparatus removal and the healing index for the series averaged 47 d/cm (range, 20-73 d/cm). Using serial DEXA scans during the consolidation phase of lengthening has a low rate (3.6%) of fractures while maintaining an acceptable bone healing index without excessively increasing fixation time.

LEVEL OF EVIDENCE

Level IV, therapeutic retrospective study. See the Guidelines for Authors for a complete description of levels of evidence.

Submuscular plating after distraction osteogenesis in children

Although distraction osteogenesis has solved limb length discrepancies, many complications are inevitable from long duration of external fixation. Use of intramedullary nails for early removal of fixators has its own challenges especially in pediatric age group. To facilitate early removal of external fixators in children, we tried a novel method of submuscular plating over the distraction callus, which is described, and the results and complications of this technique are presented. In eight children (four girls and four boys), of limb lengthening (four cases) and bone transport (four cases) done in three femurs and five tibiae with external fixators (five Ilizarov ring fixators and three monofixators), submuscular plating was done over the distraction callus. The causes of limb length discrepancy included traumatic and septic growth arrest, congenital pseudoarthrosis of tibia, fibular hemimelia, tumor salvage, and Perthes' disease. The purpose of plating was to remove the external fixator earlier after achieving the target length. Mean age of plating procedure was 11.62 years, and mean amount of distraction was 5.47 cm. In all patients, the distraction callus healed on maintaining its length or correcting into the original alignment. The mean external fixation index was 26.93 days/cm and healing index was 52.01 days/cm. One complication of superficial pin-track infection occurred, which resolved completely with conservative treatment. None of the patients developed deep infection or implant failures. The mean follow-up after plating was 28 months (range, 18-62 months). Submuscular plating over the distraction callus may be a successful method that permits early removal of fixator with fewer complications. This method can be a useful alternative in children or when nailing is difficult.

Limb lengthening over a nail can safely reduce the duration of external fixation

BACKGROUND

Limb lengthening using Ilizarov external fixation is safe, but the consolidation phase tends to take too long. A method that can safely reduce the time spent in external fixation would help increase patient tolerance and comfort. We report our results of lengthening over nails (LON) method in which an interlocking nail was used along with an Ilizarov external fixator to reduce external fixation duration in limb lengthening. This is a retrospective study.

MATERIALS AND METHODS

Twenty-seven lengthening surgeries were done with the LON method in 23 patients with 22 tibiae and five femora during the last 12 years. Length gain ranged from 1.5 cm to a maximum of 9.8 cm with a mean of 4.6 cm. The mean modified Paley difficulty score was 7.6 points. Fourteen associated procedures were performed in these patients, including equinus contracture releases, supracondylar osteotomies, ilizarov hip reconstruction and ankle fusion. We had a 29% rate of complications which included one problem, three obstacles and four complications with no serious deep intramedullary infections. Our rate of complications compares favorably with series reported in the literature. External fixation duration was reduced significantly to a mean of 17.8 days per cm.

CONCLUSIONS

A combination of intramedullary nailing along with external fixation significantly reduces external fixation time while maintaining low rate of complications. Great care needs to be taken to prevent pin track infection and deep intramedullary sepsis.

Leg lengthening with a motorized nail in adolescents : an alternative to external fixators?

Leg lengthening by external fixation is associated with various difficulties. We evaluated eight adolescent patients who underwent leg lengthening with a motorized intramedullary lengthening device. We asked whether this method could reduce the time of hospitalization and rehabilitation and whether the incidence of complications commonly associated with external fixators could be reduced. We compared our preliminary results with those from other reports, with a focus on leg length achieved, time of rehabilitation, and rate of complications. The average leg-length discrepancy was 3.8 cm (range, 3-5 cm). The average lengthening distance was 3.8 cm (range, 2.9-4.7 cm). In six patients, leg lengthening was combined with successful correction of the mechanical axis alignment. The consolidation index averaged 26 days/cm (range, 19-41 days/cm). The average hospital stay was 9.6 days. No bone or soft tissue infections were observed. In comparison to other studies (1.0-2.8 complications/patient), our results suggest that the difficulties commonly associated with external fixators can be reduced with this method. It also allows good angular correction in patients with mechanical axis deviation. These features combined with a short time of hospitalization and rehabilitation make it a promising procedure for limb lengthening.

LEVEL OF EVIDENCE

Level IV Therapeutic study.