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.

Distraction osteogenesis through an externally applied fixator is a well-established treatment for lower limb lengthening (De Bastiani et al. 1987, Paley 1988, Ilizarov 1990). However, complication rates of this treatment are high, amounting to 1–3.2 complications per patient (Tjernström et al. 1994, Noonan et al. 1998). The wires or pins penetrating soft tissues result in complications such as pin site infection, pain, scarring, muscle transfixation, reduced joint movement, and immobility (Paley 1990, Mazeau et al. 2012, Landge et al. 2015). When the external fixator is removed, there is a risk of further complications such as fracture or malalignment (Noonan et al. 1998, Simpson and Kenwright 2000). To reduce complications and improve patient comfort, limb lengthening by fully implantable bone lengthening nails has been introduced (Guichet 1999, Cole et al. 2001). Problems with purely mechanically driven lengthening nails were resolved by the introduction of motorized (FITBONE) or magnetically driven (PRECICE) bone lengthening nails (Baumgart et al. 1997, Kirane et al. 2014, Paley et al. 2014, Shabtai et al. 2014). A few case-control studies have compared these nails with external fixation (13–15 patients), and the largest case series on intramedullary bone lengthening reports on 92 patients (Black et al. 2015, Horn et al. 2015, Calder et al. 2019). However, the majority of reports of complications of the FITBONE and PRECICE lengthening nails are small case series (Krieg et al. 2008, Dinçyürek et al. 2012, Birkholtz and De-Lange 2016, Hammouda et al. 2017). In recent years motorized intramedullary lengthening nails have become increasingly popular, and we thus hypothesized that standardized data on complications could now be extracted from the literature. We performed a systematic literature review of complications using PRECICE and FITBONE bone lengthening nails in lower limb bone lengthening. The primary outcome was risk of complications imposing a new pathology or permanent sequelae in the patient.     

Limb lengthening and correction of deformity in the lower limbs of children with osteogenesis imperfecta

We performed limb lengthening and correction of deformity of nine long bones of the lower limb in six children (mean age, 14.7 years) with osteogenesis imperfecta (OI). All had femoral lengthening and three also had ipsilateral tibial lengthening. Angular deformities were corrected simultaneously. Five limb segments were treated using a monolateral external fixator and four with the Ilizarov frame. In three children, lengthening was done over previously inserted femoral intramedullary rods. The mean lengthening achieved was 6.26 cm (mean healing index, 33.25 days/cm). Significant complications included one deep infection, one fracture of the femur and one anterior angulation deformity of the tibia. The abnormal bone of OI tolerated the external fixators throughout the period of lengthening without any episodes of migration of wires or pins through the soft bone. The regenerate bone formed within the time which is normally expected in limb-lengthening procedures performed for other conditions. We conclude that despite the abnormal bone characteristics, distraction osteogenesis to correct limb-length discrepancy and angular deformity can be performed safely in children with OI.     

Humeral lengthening and deformity correction with the multiaxial correction system

Limb lengthening for humeral length discrepancy is typically accomplished using a traditional monolateral external fixator frame or an Ilizarov-type device, which have distinct shortcomings for the correction of concomitant deformity and application to the upper extremity, respectively. A new monolateral frame, the multiaxial correction (MAC) system, provides advantage over other monolateral frames and Ilizarov-type devices for humeral lengthening and may achieve similar outcomes. The purpose of this study was to report on the use of the MAC system for limb lengthening in pediatric patients, each with humeral length discrepancy and deformity. Surgical technique for applying the frame to the humerus is described briefly. A retrospective review of all pediatric patients with humeral length discrepancy treated with the MAC system by one orthopedic surgeon at a major teaching hospital was performed. Clinical data, operative records, and radiographs were reviewed for each patient. A total of three humeri in three children were lengthened over a 3-year period. There were two girls and a boy, with a mean age of 10.3 ± 1.9 years. Etiologies for their discrepancies were osteomyelitis and posttraumatic physeal arrest. Mean initial humeral length discrepancy was 9.4 ± 2.3 cm. All patients had proximal varus deformities, which were partially corrected during treatment. Mean lengthening was 6.5 ± 0.8 cm, and mean healing index was 27.1 ± 4.1 days/cm. Mean follow-up was 23.0 ± 9.9 months. There were no major complications. In conclusion, the MAC system is well suited to the correction of humeral length discrepancies and associated humeral deformities in children. Level of evidence: level IV case series.     

Femoral lengthening in young patients: An evidence-based comparison between motorized lengthening nails and external fixation

BACKGROUNDFemoral lengthening is a procedure of great importance in the treatment of congenital and acquired limb deficiencies. Technological advances have led to the latest designs of fully implantable motorized intramedullary lengthening nails. The use of these nails has increased over the last few years.AIMTo review and critically appraise the literature comparing the outcome of femoral lengthening in children using intramedullary motorized lengthening nails to external fixation.METHODSElectronic databases (MEDLINE, CINAHL, EMBASE, Cochrane) were systematically searched in November 2019 for studies comparing the outcome of femoral lengthening in children using magnetic lengthening nails and external fixation. The outcomes included amount of gained length, healing index, complications and patient reported outcomes.RESULTSOf the 452 identified studies, only two (retrospective and non-randomized) met the inclusion criteria. A total of 91 femora were included. In both studies, the age of patients treated with nails ranged from 15 to 21 years compared to 9 to 15 years for patients in the external fixation group. Both devices achieved the target length. Prevalence of adverse events was less in the nail (60%-73%) than in the external fixation (81%-100%) group. None of the studies presented patient reported outcomes.CONCLUSIONThe clinical effectiveness of motorized nails is equivalent or superior to external fixation for femoral lengthening in young patients. The available literature is limited and does not provide evidence on patient quality of life or cost effectiveness of the interventions.     

Limb lengthening with simultaneous correction of deformities]

In congenital malformation of the limbs the shortening of the extremity appears frequently together with its deformity. With Ilizarov's apparatus the limb may be lengthened simultaneously with the correction of the deformity. In spite of the fact that the use of the apparatus is rather complicated and complications are frequent, in 75 cases out of 102 excellent, in 23 good results were achieved. The various indications and results are demonstrated in 7 cases.     

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.     

Humeral lengthening and deformity correction in Ollier's disease: distraction osteogenesis with a multiaxial correction frame

A case of Ollier's disease with deformity and shortening of the humerus is presented. Lengthening of 9 cm and deformity correction of 50 degrees were accomplished with excellent functional and cosmetic results. Unique features of this case were the use of a multiaxial correction monolateral frame and the formation of normal bone within the region of diseased Ollier's bone.     

Tibial lengthening and concomitant foot deformity correction in 14 patients with permanent deformity after poliomyelitis

Background In neuromuscular diseases, limb lengthening and foot deformity correction are associated with a high risk of complications associated with distraction callus and joint contracture. We have found no published articles of tibial lengthening and concomitant foot deformity correction using the Ilizarov method or traditional methods. To compare result of gradual distraction with triple arthrodesis for foot deformity combined with tibial lengthening, we investigated healing index and complications of two methods.

Patients and methods We reviewed 14 patients with permanent deformity after poliomyelitis who underwent tibial lengthening and concomitant foot deformity correction using the Ilizarov external fixator. Tibial lengthening over an intramedullary nail was performed in 3 patients and lengthening without a nail was performed in 11 patients.

Results The mean external fixation time was 6 (3.6- 10) months without nail and 1.6 (1.5-1.7) months with nail, whereas the mean healing index was 1.8 (0.8-3.1) months/cm without nail and 2 (1.8-2.3) months/cm with nail. Concomitant foot treatments included triple arthrodesis in 7 patients, pantalar arthrodesis in 2 patients with fiail ankle, and gradual foot frame distraction without bony foot procedures in 5 patients. Delayed consolidation and recurrent equinus contracture of the ankle requiring additional lengthening of the Achilles tendon were the most common bone and joint complications during tibial lengthening.

Interpretation The gradual foot frame distraction method was associated with major complications, such as recurrent foot deformity, joint luxation, and arthritis. We therefore recommend triple arthrodesis as a concomitant procedure during tibial lengthening     

Tibial lengthening and concomitant foot deformity correction in 14 patients with permanent deformity after poliomyelitis

BACKGROUND: In neuromuscular diseases, limb lengthening and foot deformity correction are associated with a high risk of complications associated with distraction callus and joint contracture. We have found no published articles of tibial lengthening and concomitant foot deformity correction using the Ilizarov method or traditional methods. To compare result of gradual distraction with triple arthrodesis for foot deformity combined with tibial lengthening, we investigated healing index and complications of two methods. PATIENTS AND METHODS: We reviewed 14 patients with permanent deformity after poliomyelitis who underwent tibial lengthening and concomitant foot deformity correction using the Ilizarov external fixator. Tibial lengthening over an intramedullary nail was performed in 3 patients and lengthening without a nail was performed in 11 patients. RESULTS: The mean external fixation time was 6 (3.6-10) months without nail and 1.6 (1.5-1.7) months with nail, whereas the mean healing index was 1.8 (0.8-3.1) months/cm without nail and 2 (1.8-2.3) months/cm with nail. Concomitant foot treatments included triple arthrodesis in 7 patients, pantalar arthrodesis in 2 patients with flail ankle, and gradual foot frame distraction without bony foot procedures in 5 patients. Delayed consolidation and recurrent equinus contracture of the ankle requiring additional lengthening of the Achilles tendon were the most common bone and joint complications during tibial lengthening. INTERPRETATION: The gradual foot frame distraction method was associated with major complications, such as recurrent foot deformity, joint luxation, and arthritis. We therefore recommend triple arthrodesis as a concomitant procedure during tibial lengthening     

Functional outcome after lengthening with and without deformity correction in polio patients

Poliomyelitis is one of the causes of limb length discrepancy. The aim of lengthening and deformity correction in such patients is to improve the functional mobility of the patient. This study aims to find out whether or not improvement of limb length inequality with or without deformity correction affects or improves ambulation. This prospective study included 32 skeletally mature patients managed using the Ilizarov technique and external fixation for limb lengthening with or without deformity correction. Functional Mobility Scale scoring was used for assessment of ambulation before lengthening and at the final follow-up. The average duration of follow-up was 2 years and 9 months. Lengthening alone did not change the Functional Mobility Scale score. While lengthening associated with deformity correction improved the mobility scale at 5 m only (in the house), it had no effect on the 50 and 500 m score.     

Tibial lengthening over humeral and tibial intramedullary nails in patients with sequelae of poliomyelitis: a comparative study

Leg discrepancy is common after poliomyelitis. Tibial lengthening is an effective way to solve this problem. It is believed lengthening over a tibial intramedullary nail can provide a more comfortable lengthening process than by the conventional technique. However, patients with sequelae of poliomyelitis typically have narrow intramedullary canals allowing limited space for inserting a tibial intramedullary nail and Kirschner wires. To overcome this problem, we tried using humeral nails instead of tibial nails in the lengthening procedure. In this study, we used humeral nails in 20 tibial lengthening procedures and compared the results with another group of patients who were treated with tibial lengthening over tibial intramedullary nails. The mean consolidation index, percentage of increase and external fixation index did not show significant differences between the two groups. However, less blood loss and shorter operating time were noted in the humeral nail group. More patients encountered difficulty with the inserted intramedullary nail in the tibial nail group procedure. The complications did not show a statistically significant difference between the two techniques on follow-up. In conclusion, we found the humeral nail lengthening technique was more suitable in leg discrepancy patients with sequelae of poliomyelitis.     

Acute correction of lower limb deformity and simultaneous lengthening with a monolateral fixator

We have reviewed, retrospectively, all children with a lower limb deformity who underwent an acute correction and lengthening with a monolateral fixator between 1987 and 1996. The patients were all under the age of 19 years and had a minimum follow-up of eight months after removal of the fixator. A total of 41 children had 57 corrections and lengthening. Their mean age was 11.3 years (3.2 to 18.7) and there were 23 girls and 18 boys. The mean maximum correction in any one plane was 23 degrees (7 to 45). In 41 bony segments (either femur or tibia) a uniplanar correction was made while various combinations were carried out in 16. The site of the osteotomy was predominantly diaphyseal, at a mean of 47% (17% to 73%) of the total bone length and the mean length gained was 6.4 cm (1.0 to 17.0). Univariate analysis identified a moderately strong relationship between the bone healing index (BHI), length gained, maximum correction and grade-II to grade-III complications. For logistic regression analysis the patients were binary coded into two groups; those with a good outcome (BHI < or = 45 days/cm) and those with a poor outcome (BHI > 45 days/cm). Various factors which may influence the outcome were then analysed by calculating odds ratios with 95% confidence intervals. This analysis suggested a dose response between increasing angular correction and poor BHI which only reached statistical significance for corrections of larger magnitude. Longer lengthenings were associated with a better BHI while age and the actual bone lengthened had little effect. Those patients with a maximum angulatory correction of less than 30 degrees in any one plane had an acceptable consolidation time with few major complications. The technique is suitable for femoral deformity and shortening, but should be used with care in the tibia since the risk of a compartment syndrome or neurapraxia is much greater.     

Calcaneal lengthening: investigation of deformity correction in a cadaver flatfoot model

BACKGROUND: Evans showed that lengthening the lateral column by inserting structural bone graft into the anterior calcaneus could correct abduction and valgus deformity in flatfoot. To better understand the mechanism of correction and the three-dimensional effect of this procedure a cadaver study was done. METHODS: Three cadaver flatfoot models were used. Computed tomographic (CT) scans were made of each specimen before and after lengthening. Data from these scans were used to determine the center of volume of the talus, navicular, cuboid, and calcaneus. The angular and translational motions for each bone were determined. RESULTS: On average, relative to the talus, the navicular moved 18.6 degrees of rotation in adduction, 2.6 degrees of rotation in pronation, and 3.4 degrees in plantarflexion. The average translation was 5.6 mm medial, 0.4 mm posterior, and 1.8 mm plantar. The cuboid moved an average of 24.2 degrees of rotation in adduction and lengthening, 13.9 degrees in pronation, and 1.9 degrees in plantarflexion. The average translation was 9.4 mm medial, 2.6 mm distal, and 1.5 mm plantar. The calcaneus moved an average of 4.4 degrees of rotation in adduction, 0.1 degrees of rotation in eversion, and 1.3 degrees of plantarflexion. The average translation was 3 mm medial and 0.7 mm posterior with no plantar translation. CONCLUSIONS: The mechanism of Evans calcaneal lengthening involves adduction and plantarflexion of the midfoot relative to the hindfoot. The cuboid and navicular appear to move as a unit. The shape of the talar head, axis of the subtalar joint, degree of initial deformity, competence of plantar soft tissues, such as the long plantar ligament, and adequate length of the Achilles tendon are important. Knowing what qualitative three-dimensional changes take place allows a better understanding of the mechanics of the procedure and its possible applications.     

Pitfalls of lengthening over an intramedullary nail in tibia: a consecutive case series

Background  

Lengthening over a nail was introduced to reduce the overall complication rate in the classic Ilizarov method. Previous studies reported that an intramedullary nail could decrease the time of external fixation, prevent anatomic malalignment and collapse; Internal friction, damage to endosteal blood supply and infection rates, however, may be higher. Whether the approach achieves it goals with acceptable complication rates is unclear. The aim of this study was to describe the results and complications of tibial lengthening over a nail.     

Biomechanical evaluation of primary stiffness of tibiotalocalcaneal fusion with intramedullary nails

BACKGROUND: Intramedullary implants are being used with increasing frequency for tibiotalocalcaneal fusion (TTCF). Clinically, the question arises whether intramedullary (IM) nails should have a compression mode to enhance biomechanical stiffness and fusion-site compression. This biomechanical study compared the primary stability of TTCF constructs using compressed and uncompressed retrograde IM nails and a screw technique in a bone model. METHODS: For each technique, three composite bone models were used. The implants were a Biomet nail (static locking mode and compressed mode), a T2 femoral nail (compressed mode); a prototype IM nail 1 (PT1, compressed mode), a prototype IM nail 2 (PT2, dynamic locking mode and compressed mode), and a three-screw construct. The compressed contact surface of each construct was measured with pressure-sensitive film and expressed as percent of the available fusion-site area. Stiffness was tested in dorsiflexion and plantarflexion (D/P), varus and valgus (V/V), and internal rotation and external rotation (I/E) (20 load cycles per loading mode). RESULTS: Mean contact surfaces were 84.0 +/- 6.0% for the Biomet nail, 84.0 +/- 13.0% for the T2 nail, 70.0 +/- 7.2% for the PTI nail, and 83.5 +/- 5.5% for the compressed PT2 nail. The greatest primary stiffness in D/P was obtained with the compressed PT2, followed by the compressed Biomet nail. The dynamically locked PT2 produced the least primary stiffness. In V/V, PT1 had the (significantly) greatest primary stiffness, followed by the compressed PT2. The statically locked Biomet nail and the dynamically locked PT2 had the least primary stiffness in V/V. In I/E, the compressed PT2 had the greatest primary stiffness, followed by the PT1 and the T2 nails, which did not differ significantly from each other. The dynamically locked PT2 produced the least primary stiffness. The screw construct's contact surface and stiffness were intermediate. CONCLUSIONS: The IM nails with compression used for TTCF produced good contact surfaces and primary stiffness. They were significantly superior in these respects to the uncompressed nails and the screw construct. The large contact surfaces and great primary stiffness provided by the IM nails in a bone model may translate into improved union rates in patients who have TTCF.