Intramedullary Lengthening Nails Research Articles

Research progress of intramedullary lengthening nail technology

To review the research progress of intramedullary lengthening nail technology. The foreign literature on the development history, types, advantages and disadvantages, indications and contraindications, complications, and effectiveness of intramedullary lengthening nail were reviewed and analyzed. The intramedullary lengthening nail system mainly includes mechanical type, electric motor drive type, and magnetic drive type. Compared with traditional external fixation and lengthening technology, the intramedullary lengthening nail technology has certain advantages in incidence of complications, bone healing, postoperative functional rehabilitation, incision aesthetics, convenience, and patient satisfaction. However, there are also shortcomings, such as pain, uncontrollable distraction rate, device failure, etc. In the clinical application of intramedullary lengthening nails for limb lengthening, the indications should be grasped reasonably, and the related complications should be prevented and treated. Intramedullary lengthening nails provide a new option for limb lengthening, and the initial effectiveness is good. It is one of the development direction of limb lengthening technology.

Retrograde Extramedullary Lengthening of the Femur Using the PRECICE Nail: Technique and Results.

Lengthening of long bones by distraction osteogenesis is now possible using intramedullary lengthening nails. Constraints of bone size, medullary canal obstruction, and the presence of an open physis are contraindications in skeletally immature patients. We present a technique describing the "off-label" use of a magnetic lengthening nail placed extramedullary and in retrograde manner, for lengthening of the femur in skeletally immature patients. A retrospective review of 5 skeletally immature patients with significant length discrepancy of the femur are presented along with a description of the surgical technique. Data collected included age, sex, date of surgery, diagnosis, presence of associated deformities, the magnitude of length discrepancy, the amount of length gained, the amount of time to achieve full weight-bearing, the time to hardware removal, and any complications. There were 5 patients (3 females). The mean age was 7.2±2.7 years (4 to 10 y). The mean limb length discrepancy was 6.5±3.7 cm (3.5 to 11 cm). A mean length of 3.46±0.4 cm (3.1 to 4 cm) was achieved which represents 12.9±1.8% (10.32 to 13.47%) of the bone length. The time taken to achieve full weight-bearing ambulation was 89.2±19.3 days (60 to 109 d) or 12.7 weeks. All hardware was removed 247.6±215.6 days (99 to 628 d) after surgery. Patients were followed up for a mean duration of 19.2 months (11 to 30 mo). No supplemental fixation was required and no complications were noted. Acute deformity correction was also performed at the time of surgery in 2 patients who had distal femur valgus deformity. Retrograde extramedullary lengthening of the femur is an option that should be considered for limb length equalization in skeletally immature patients. It avoids the inconvenience of external fixation and can be used to simultaneously correct deformities of the distal femur. Although the total amount of length gained is modest, we believe it is a promising limb lengthening technique that merits further investigation. Level III.

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.

Patient perspectives in the choice of management of leg length discrepancy

Background: The traditional limb length discrepancy management algorithm dictates that patients with less than 5 centimeters (cm) of leg length discrepancy should not be offered lengthening surgery as a treatment option. With the development of intramedullary lengthening nails, the procedure for limb lengthening has become more patient friendly and reliable. This study investigated current patient preferences for management when faced with a projected final length discrepancy of less than 5 cm. Materials and Methods: Following IRB approval, a retrospective chart review of a single surgeon's experience with patients presenting with clinical and radiological evidence of limb length discrepancy between 2017 and 2020 was performed. Patients were excluded from the study if the final discrepancy or projected discrepancy was more than 5 cm. The same management options for the LLD were presented to each patient and their family: 1) Observation, 2) Shoe lift, 3) Epiphysiodesis/Acute shortening of the longer limb, 4) Limb lengthening of the shorter limb. Results: Sixty-two (62) patients met the inclusion criteria. This was comprised of 45 skeletally immature patients and 17 skeletally mature patients. Forty-four (44) patients (71% of the entire group) preferred to have the shorter limb lengthened. This represents 27 (60%) of the skeletally immature patients and all 17 (100%) of the skeletally mature patients. No patients chose acute shortening or a shoe lift as definitive management. Conclusion: With 71% of patients opting for a lengthening procedure, this study demonstrates that patients prefer limb lengthening over limb shortening for discrepancies less than 5 cm. With improvements in the knowledge and techniques of limb lengthening as well as better patient experience particularly with the intramedullary lengthening nails, surgeons should not feel obligated to only offer lengthening to patients with LLD > 5 cm.

Multicentre review of intramedullary lengthening nails: A middle-income country perspective

Background: Lengthening nails (ILN) are an established method of limb reconstruction for leg length discrepancy (LLD). Literature on these nails is predominantly from developed countries, with more accessible resources for the procurement of devices and post-operative therapies. This paper aims to present the results and lessons learned from four tertiary level limb reconstruction units working within two middle-income countries (MIC). Methods: Ethical approval was obtained from all four units. All ILN (PRECICE II, NuVasive, USA) undertaken between 2013 and 2020 were included. Demographics, etiology, surgical approach, and information about the planned versus achieved correction were compared. Data on time to consolidation and complications were recorded with a 12-month minimum follow-up. Complications were classified according to the Black et al. criteria. Results: Sixty limb segments lengthened in 56 patients, of which 46 were femora, 12 tibiae and two humeri. Etiology of LLD was predominately posttraumatic (33%), congenital (26%), and growth plate injuries (22%). Mean distraction length was 46 mm (20–90 mm). Fifty-four segments (90%) had <5 mm discrepancy of planned distraction lengths. Mean healing index was 34.6 days/cm (range: 18–180 days/cm). Thirteen patients experienced complications, of which ten required further surgery. Conclusion: The findings of our work support the use of intramedullary ILN in MIC with equivalent complication rates and healing indices compared to the literature. Patient compliance and remote geography were not an issue during treatment. The lack of access to weekly rehabilitation therapy did not seem to impact the majority of patients. Reusing nails for extensive LLD cases were safe but should be used with caution.

Multicentre Review of Intramedullary Lengthening Nails: A Middle-Income Country Perspective

Multicentre Review of Intramedullary Lengthening Nails: A Middle-Income Country Perspective

Systematic review of complications with externally controlled motorized intramedullary bone lengthening nails (FITBONE and PRECICE) in 983 segments

Background and purpose — In recent years motorized intramedullary lengthening nails have become increasingly popular. Complications are heterogeneously reported in small case series and therefore we made a systematic review of complications occurring in lower limb lengthening with externally controlled motorized intramedullary bone lengthening nails. Methods — We performed a systematic search in PubMed, EMBASE, and the Cochrane Library with medical subject headings: Bone Nails, Bone Lengthening, and PRECICE and FITBONE nails. Complications were graded on severity and origin. Results — The search identified 952 articles; 116 were full text screened, and 41 were included in the final analysis. 983 segments were lengthened in 782 patients (age 8–74 years). The distribution of nails was: 214 FITBONE, 747 PRECICE, 22 either FITBONE or PRECICE. Indications for lengthening were: 208 congenital shortening, 305 acquired limb shortening, 111 short stature, 158 with unidentified etiology. We identified 332 complications (34% of segments): Type I (minimal intervention) in 11% of segments; Type II (substantial change in treatment plan) in 15% of segments; Type IIIA (failure to achieve goal) in 5% of segments; and Type IIIB (new pathology or permanent sequelae) in 3% of segments. Device and bone complications were the most frequent. Interpretation — The overall risk of complications was 1 complication for every 3 segments lengthened. In 1 of every 4 segments, complications had a major impact leading to substantial change in treatment, failure to achieve lengthening goal, introduction of a new pathology, or permanent sequelae. However, as no standardized reporting method for complications exists, the true complication rates might be different.

Pediatric Lower Limb Lengthening Using the PRECICE Nail: Our Experience With 50 Cases.

Limb lengthening using intramedullary externally controlled motorized devices is becoming increasingly popular. There is limited literature regarding their use in the pediatric and adolescent population. This study reviews outcomes on 50 consecutive cases of intramedullary lower limb lengthening surgery in this population. A retrospective review of all pediatric and adolescent patients treated in our institution by intramedullary lengthening for lower limb length discrepancy using the PRECICE and STRYDE intramedullary lengthening nails between 2013 and 2019. All patients were operated by a single surgeon. Data were prospectively recorded. We report on nail accuracy and reliability, consolidation index, time to full weight-bearing from completion of lengthening, joint range of movement, ASAMI bone and functional scores, presence of problems, obstacles and complications, and patient reported outcome measures (PROMS). Fifty cases (43 femoral and 7 tibial nails) were performed in 42 patients (20 males, 48% and 22 females, 52%). Six patients had bilateral lengthening and 2 patients had sequential lengthening. There were 28 antegrade femoral, 13 retrograde femoral and 5 tibia PRECICE nails, 2 tibial and 2 femoral PRECICE STRYDE nails. Mean age at surgery was 15 years old (12 to 17). Mean preoperative length discrepancy was 49 mm (20 to 90). Mean achieved lengthening was 46.5 mm (20 to 80). Mean percentage lengthening was 12.6% (5% to 25%). Nail accuracy was 96% and reliability 90%. Average distraction rate was 0.92 mm/d for femur and 0.64 mm/d for tibias. Consolidation index was 28 d/cm (18 to 43) and 39 d/cm (20 to 47), respectively. Time from completion of lengthening to independent full weight-bearing as observed in clinic was 45 days (21 to 70) and 34.2 days (23 to 50), respectively. ASAMI bone and functional scores were favorable and PROMS demonstrated high patient satisfaction levels. No significant complications were observed. We have demonstrated excellent clinical results and high patient satisfaction with intramedullary lengthening in a pediatric/adolescent population. We highly recommend thorough preoperative preparation, patient education, and a multidisciplinary approach. Level IV.

Principles of Motorized Internal Lengthening of Long Bones

Motorized intramedullary lengthening nails (ILNs) have revolutionized limb lengthening surgery and led to an expansion of indications utilizing them for both upper and lower limb lengthening, fracture compression, and nonunion treatment. There are biological and mechanical differences between using ILNs and using external fixators for lengthening surgery that the treating surgeon must be familiar with. Biological factors include regenerate quality, healing indices, and regenerate complications. Mechanical differences pertain to the lengthening axis, stability, and postoperative weight-bearing. Practical principles of ILNs use such as nail selection (entry point, nail length, lengthening nail problems), use of blocking screws, soft tissue releases (for nerve decompression, joint subluxation, and contractures) and physical therapy protocols are discussed.

Long Bone Lengthening in Children

Intramedullary lengthening nails have revolutionized the field of limb lengthening. Although pediatric patients can benefit from this new technology, the size of the bones and the presence of open physes create potential impediments that must be recognized by the surgeon. This review of pediatric intramedullary limb lengthening describes the key elements and nuances that will help guide the surgeon towards a successful outcome.

Motorized Internal Limb Lengthening: International Perspectives

The remote-controlled, motorized, intramedullary lengthening nail is a disruptive technology that has fundamentally changed the approach to limb lengthening and reconstruction surgery globally. This new paradigm for limb reconstruction, marked by a decreased need for external fixation, has ignited a fervor among limb deformity surgeons. Although the origins of the Ilizarov method of distraction osteogenesis are deeply entwined with circular external fixation, the disadvantages of external fixators are well known and include pin track infections, skin pain, soft-tissue tethering, and joint stiffness. Integrated fixation techniques were developed combining internal and external fixation such as lengthening over a nail, lengthening and then nailing, lengthening and then plating, and bone transport over a nail to minimize the treatment time in external fixation. Building on these incremental advances, bone lengthening with a fully implantable device has enabled us to entirely avoid external fixation in most cases. Early designs of the internal lengthening nail (ILN) were telescopic and lengthened through a ratchet mechanism requiring mechanical rotation of the limb. Issues with mechanical integrity and accurate control of distraction by these implants have vastly improved over the last decade with the latest remote-controlled ILN delivering a predictable outcome. The remote-controlled ILN is available in different nail types with varied mechanics, material properties, and surgical indications. One design employs an electric motor imbedded into the telescopic rod, activated by intermittent transcutaneous transmission of radiofrequency waves to an implanted antennae/receiver which converts these waves into an electrical impulse discharged via a connecting cable. The second design, now most widely used in the United States, is a telescopic rod with a magnetic drive mechanism, activated by a hand-held external electromagnetic actuator. Furthermore, in addition to the functional mechanism differences, there are nails made from titanium or from stainless steel, and these have different biomechanical properties. The indications range by bone and nail orientation. The femur can be approached antegrade through a piriformis or greater trochanteric entry or can be entered retrograde. A short residual femur after amputation can be lengthened with a specially designed nail. The tibia is approached antegrade. Although the ILNs are primarily used for distraction osteogenesis bone lengthening, the magnetic ILN can also be used for compression of nonunions. In the last several years, there has been some experience with bone transport nails but recently, a motorized magnetic bone transport nail for treatment of segmental bone defects up to 10 cm has been launched, and the early experience is currently being accumulated. Creative, off-label uses of the commercially available nails have included humerus lengthening, retrograde tibia through an ankle/subtalar arthrodesis, extramedullary lengthening with a nail, and bone transport over a plate. Additional internal lengthening designs are in development including humerus nails, ankle fusion/retrograde tibia nails, and internal lengthening plates. In the absence of angular deformity, lengthening of a long bone with the ILN is an ideal surgical indication. Rotation may be corrected over the nail. Blocking screws may be needed to prevent predictable deformities that occur during lengthening. In the presence of preoperative angular deformity, adjuvant techniques such as fixator assisted nailing and blocking screws may be utilized in many, but not all cases, to acutely correct deformity and then gradually lengthen with the ILN. With increased periosteal disruption, latency and distraction may need to be modified. In addition, a staged approach may be used where deformity correction is performed and then at a second surgery, lengthening with the ILN is done. Furthermore, a bifocal approach may be used where deformity correction is performed at one end of the bone and lengthening with the ILN is done at the other end of the bone. The ILNs have created excitement among surgeons from separate sub specialties and diverse nationalities. Both pediatric and adult patients share common pathologies that require bone lengthening and deformity correction including congenital and posttraumatic deformity and leg length discrepancy. These pathologies have inspired global collaboration between orthopedists trained in pediatrics, trauma, foot and ankle, oncology, sports, knee/hip reconstruction, or limb deformity. Through annual meetings and a common body of literature, we all come together to teach and learn from each other. The motorized ILN is an ingenious technology has encouraged us to build new paradigms for limb reconstruction surgery. Although there is continued need for external fixation in selected cases, the modern limb deformity surgeon will use the ILN when possible. The ILN is, however, not available yet in many developing countries. In this edition of Techniques in Orthopedics, dedicated to internal limb lengthening, we have gathered an international panel of experts to discuss specialized applications of this most recent evolution of the Ilizarov method.

Compression of Nonunions With the PRECICE Magnetic Intramedullary Compression Nail

The magnetic intramedullary lengthening nail can be predistracted and used to compress bony interfaces to assist in the healing of nonunions of long bones and to accelerate union at difficult to heal fractures and osteotomy sites. This requires no special implant apart from the lengthening nail. Technical considerations include predistraction of the nail on the back table, overreaming of the canal, shortening at the defect site, and applying compression over several days. Patients can weight-bear immediately and often return to work quickly. The same nail can be used for bone lengthening, after union is achieved, by creating an osteotomy around the implant. Results show high union rates with minimal morbidity.

Motorized Intramedullary Lengthening Nails: Outcomes and Complications

The outcomes of motorized intramedullary lengthening nails are overwhelmingly good with acceptable complication rates and high surgeon satisfaction. While patients report overwhelming approval to surgeons, universal orthopedic outcomes scores fail to capture the true benefits of these procedures. Many studies have been cited in table format in this report. Pearls from experienced surgeons are reviewed and include the benefits of antegrade nailing over retrograde, prophylactic soft tissue release, and blocking screw use. Pitfalls are explored to keep the reader vigilant for mechanical failure of the nail, delayed healing, and common tibial difficulties. Through compiling data, estimates of collective complication incidence are presented.

Tibial lengthening using a retrograde magnetically driven intramedullary lengthening device in 10 patients with preexisting ankle and hindfoot fusion

Background and purpose — Motorized intramedullary lengthening nails (ILNs) have been developed as an alternative to external fixators for long bone lengthening. The antegrade approach represents the standard method for tibial ILN insertion. In patients with preexisting ankle and hindfoot fusion a retrograde approach provides an alternative technique that has not been evaluated so far. We report the outcome of this method in 10 patients. Patients and methods — This retrospective study included 10 patients (mean age 18 years [13–25]) with preexisting ankle and hindfoot fusion who underwent tibial lengthening with a retrograde ILN (PRECICE). The mean leg length discrepancy (LLD) was 58 mm (36–80). The underlying conditions were congenital (n = 9) and post tumor resection (n = 1). The main outcome measures were: ILN reliability, distraction achieved, distraction index (DIX), time to bone healing, consolidation index (CIX), complications, and functional results. Results — All patients achieved the goal of lengthening (mean 48 mm [26–80]). Average DIX was 0.6 mm/day (0.5–0.7) and mean CIX was 44 days/cm (26–60). Delayed consolidation occurred in 2 patients and healed after ILN dynamization or nail exchange with grafting. Toe contractures in 2 other patients were resolved with physiotherapy or tenotomy. Until last follow-up (mean 18 months [12–30]) no true complications were encountered, knee motion remained unaffected, and full osseous consolidation occurred in all patients. Interpretation — In patients with LLD and preexisting ankle and hindfoot fusion distal tibial lengthening using a retrograde ILN is a reliable alternative to the standard approach with equivalent bone healing potential and low complication rates leaving the knee unaffected.

Extramedullary Motorized Lengthening of the Femur in Young Children.

Limb lengthening by distraction osteogenesis is now achievable via motorized intramedullary devices, mitigating many complications of lengthening by external fixation. In young patients, antegrade intramedullary nailing of the femur risks avascular necrosis of the femoral head. A method of extramedullary placement of a motorized expandable intramedullary nail has been employed by the senior author to safely achieve femoral lengthening without the use of an external fixator in young patients. Eleven skeletally immature patients with lower limb length discrepancy were reviewed who underwent extramedullary placement of a magnetic, expandable intramedullary nail for lengthening of the femur. Surgical details, lengthening parameters, and complications were reviewed and classified according to the modified Clavien-Dindo Classification. Average lengthening was 32.3 mm (range: 27 to 40 mm) comprising an average 14.8% of femoral segment length. The average lengthening duration was 6.3 weeks, and average full weight-bearing began at 12.6 weeks. All but 1 patient underwent early removal of the device at an average of 4.5 months, and 5 had immediate plating of the femur. Complications rates were comparable to other methods of femoral lengthening, including varus or procurvatum through the regenerate, and unplanned reoperation in 3 of 11 cases. Preoperative considerations included careful planning of implant length due to short femoral segments and protection of the knee joint from contracture or iatrogenic instability. Extramedullary placement of a magnetic expandable intramedullary lengthening nail can achieve lengthening of the femur without the use of external fixation. Considerations with this technique include careful planning of implant length relative to trochanteric-physeal distance, protection against knee subluxation during lengthening, and mitigating deformity of the regenerate. Off-label, extramedullary use of these devices can be considered to decrease the burdens of external fixation in young children. The technique begs the advent of future all-internal technology specifically designed for safe limb lengthening in this age group. Level IV-retrospective case series.

New Category III Code Introduced for Humeral Osteotomy With Intramedullary Lengthening Device

Effective for dates of service on and after July 1, 2020, new Current Procedural Terminology® Category III code 0594T may be reported for implantation of an externally controlled intramedullary lengthening nail via osteotomy of the humerus.

Limb lengthening in down syndrome

Introduction: The average life expectancy for Down syndrome patients has markedly improved. Musculoskeletal disorders occur in 20%–27% of patients with Down syndrome, with hip or knee instability among the most common presentations. Leg length discrepancy has rarely been reported in Down syndrome but can occur as the result of previous lower extremity surgery. This case report presents our experience with the first documented use of an intramedullary lengthening nail to correct a 4.5 cm iatrogenic leg length discrepancy in a skeletally mature Down syndrome patient. Materials and Methods: A single patient surgically treated for leg length discrepancy was followed over a 1-year period and retrospectively reviewed. Results: An 17-year-old male with Down syndrome presented with a 4.5 cm leg length discrepancy secondary to a previously attempted hip fusion. He had been treated with a shoe lift but had difficulty walking with the lift and resorted to toe walking whenever the lift was not being used. His mother, who was his full-time caregiver, was interested in surgical options for permanently correcting his discrepancy. After long discussions over multiple visits covering the risks and benefits of the various choices, the decision to proceed with lengthening of the short limb using a retrograde femoral intramedullary lengthening nail was made. Distraction osteogenesis of 4.5 cm with full consolidation was achieved in this patient without complications. He was able to return to full independent ambulation without a lift by 4 months. Conclusion: Limb lengthening requires a detailed postoperative protocol that may appear to be difficult for a Down syndrome patient with cognitive developmental delay to manage. However, this report documents that if the patient has a reliable caregiver and close postoperative monitoring is maintained, a successful outcome is possible. This represents the first published case of limb lengthening in a Down syndrome patient.

Acute deformity correction and lengthening using the PRECICE magnetic intramedullary lengthening nail

Background: External fixators have been used to treat patients with limb length discrepancy with deformity. Implantable intramedullary (IM) lengthening nails are an attractive alternative achieving accurate results with fewer complications than external fixators. We report on PRECICE™ nail utilization for simultaneous lower limb lengthening and acute deformity correction. Materials and Methods: A retrospective institutional study included a total of 22 segments (13 femurs, 9 tibias; mean age = 17 years) that underwent simultaneous acute deformity correction and lengthening using fixator-assisted nailing and the PRECICE™ IM nail between 2012 and 2015. Results: All segments were corrected with mean final mechanical axis deviation 0.8 cm (0–2.0 cm). Femoral segments achieved frontal plane correction from a preoperative mean lateral distal-femoral angle of 86° to a postoperative mean of 89°; and a sagittal plane correction from a preoperative mean posterior distal femoral angle of 76° to a postoperative mean of 84°. Tibial segments achieved frontal plane correction from a preoperative mean medial proximal tibial angle of 94° to a postoperative mean of 89°; and a sagittal plane correction from a preoperative mean posterior proximal tibial angle of 72° to a postoperative mean of 79°. Rotational malalignment was corrected in all cases based on clinical examination of the rotational profile. The mean length achieved was 4.7 cm. One femoral segment (4.5%) did not achieve the lengthening goal. The mean consolidation index was 42 days/cm. Mean distraction index was 0.7 days/mm. Conclusions: Internal lengthening can permit both lengthening and acute deformity correction, with appropriate preoperative planning, using fixator assisted nailing techniques.

Lower limb lengthening over an intramedullary nail: a long-term follow-up study of 28 cases

BackgroundLimb lengthening using an external fixator requires a long period of external fixation and may be associated with several complications such as axial deformity, fracture of the regenerated bone, and joint stiffness. With the goal of reducing the time of external fixation as well as some of these complications, we performed femoral or tibial lengthening over an intramedullary nail, according to Paley’s technique, in 28 patients, followed up after a mean period of 8 years.Materials and methodsTwenty-eight patients treated for lower limb discrepancy by limb lengthening over an intramedullary nail were reviewed from 5 to 11 years after healing of regenerated bone. There were 20 femurs and 8 tibiae, with average age at surgery of 14.2 years and average length inequality of 6.1 cm for femurs and 5.3 cm for tibiae.ResultsThe mean lengthening was 5.8 cm for femurs and 4.8 cm for tibiae. The mean period of radiographic consolidation of the regenerated bone was 6 months for femoral lengthening and 4.5 months for tibial lengthening. At follow-up, we observed 8 excellent results, 15 good results, 4 fair results, and 1 poor result, based on Paley’s evaluation criteria. The main complications were one deep infection, one nonunion of the distracted segment, one breakage of the distal fiche of the external fixator, and one breakage of both distal locking screws of the intramedullary nail.DiscussionWe believe that limb lengthening over an intramedullary nail still represents a good method to treat limb length discrepancy because it reduces the time of external fixation, prevents axial deformities and fractures of regenerated bone, and allows early rehabilitation. The new intramedullary lengthening nails, which theoretically are the ideal device for treating limb length inequality, are still very expensive and need longer follow-up for definitive evaluation.Level of evidence4.

Repeated intramedullary stabilization following failed telescopic nail lengthening – An appropriate treatment strategy

Externally magnetic-controlled intramedullary telescopic nails for bone lengthening have recently gained popularity due to many advantages when compared to more traditional lengthening methods. Patients requiring lengthening often present with a clinical history of previous multiple surgeries increasing the risk for complications of further procedures. However, studies regarding the treatment of complications following implantation of these devices remain scarce in literature. Therefore, we report our experience with revision surgery after lengthening with a telescopic intramedullary lengthening nail. In 6 out of 20 cases (30%) of lower limb lengthening for leg length discrepancy revision surgery was necessary. Two revisions were necessary due to nail breakage while the other 4 cases required a secondary procedure for non-union. In all cases, revision surgery included standard intramedullary locking nailing with additional autologous bone grafting. The median interval between index and revision surgery was 11.5 months (range 2–15 months). Satisfying clinical results, the intended extend of lengthening and bony consolidation was observed in all 6 patients. We conclude that revision surgery using an intramedullary locking nail with autologous bone grafting after failed telescopic nail-based lengthening represents an useful salvage procedure in these cases.