Aims. This study aims to enhance understanding of clinical and radiological consequences and involved mechanisms that led to corrosion of the Precice Stryde (Stryde) intramedullary lengthening nail in the post market surveillance era of the device. Between 2018 and 2021 more than 2,000 Stryde nails have been implanted worldwide. However, the outcome of treatment with the Stryde system is insufficiently reported. Methods. This is a retrospective single-centre study analyzing outcome of 57 consecutive lengthening procedures performed with the Stryde nail at the authors’ institution from February 2019 until November 2020. Macro- and microscopic metallographic analysis of four retrieved nails was conducted. To investigate observed corrosion at telescoping junction, scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDX) were performed. Results. Adjacent to the nail’s telescoping junction, osteolytic changes were observed in bi-planar radiographs of 20/57 segments (35%) after a mean of 9.5 months (95% confidence interval 7.2 to 11.9) after surgery. A total of 8/20 patients with osseous alterations (40%) reported rest and ambulation pain of the lengthened segment during consolidation. So far, 24 Stryde nails were retrieved and in 20 (83%) macroscopic corrosion was observed at the nail’s telescoping junction. Before implant removal 11/20 radiographs (55%) of lengthened segments with these 20 nails revealed osteolysis. Implant retrieval analysis by means of SEM showed pitting and crevice corrosion. EDX detected chromium as the main metallic element of corrosion. Conclusion. Patients are exposed to the risk of implant-related osteolysis of unclear short- and long-term clinical consequences. The authors advocate in favour of an early implant removal after osseous consolidation. Cite this article: Bone Joint Res 2021;10(7):425–436

Introduction. The practice of limb lengthening using intramedullary nails has surged in popularity in recent years. Our study explores the relationship between femur lengthening and overall height gain in adults undergoing cosmetic limb lengthening with telescoping magnetic intramedullary lengthening nails (MILNs). Materials & Methods. Demographic information, pre- and postoperative radiographic data, and secondary outcomes, such as mechanical angles and sagittal alignment, were analyzed for 42 adult femurs MILNs (PRECICE 2, NuVasive, Inc.). Height was assessed with a digital stadiometer. Limb lengthening was defined as the amount of nail distraction seen on a calibrated weight bearing X-ray at consolidation. mLDFA, mMPTA, MAD, AMA, and femoral sagittal bow were evaluated as secondary outcomes. Results. Mean starting height was 163.5 cm (SD 10.4, range 137–179) Post -lengthening mean height increased to 171.1 cm (SD 10.1, range 146.7–185.3). Average height gain was 7.5 cm (SD 1.3 cm, range 5.1–9.5). Average femoral lengthening was 7.3 cm (SD 1.14, range 4.1–10.1). There were no statistically significant difference between height gain and femur lengthening. Secondary outcomes showed reductions in femoral sagittal bow and AMA. Conclusions. We conclude that measuring femur lengthening is a reliable and accurate method of measuring gained height in deformity-free patients undergoing limb lengthening. We further reason that straightening of both femoral and spinal sagittal bow counteracts potential lengthening loss over the anatomical axis, versus mechanical axis lengthening

Introduction. Management of deformity involving limb length discrepancy (LLD) using intramedullary devices offers significant benefits to both patients and clinicians over traditional external fixation. Following the withdrawal of the PRECICE nail, the Fitbone became the primary implant available for intramedullary lengthening and deformity correction within our service. This consecutive series illustrates the advantages and complications associated with the use of this device, and describes a novel technique modification for antegrade intramedullary lengthening nails. Materials & Methods. A retrospective cohort review was performed of patient outcomes after treatment with the Fitbone nail at two tertiary referral limb reconstruction services (one adult, one paediatric) between January 2021 to December 2023. Aetiology, indications, initial and final LLD, use of concomitant rail assisted deformity correction (ORDER), removal time and healing index were assessed. Complications of treatment were evaluated and described in detail, alongside technique modifications to reduce the rate of these complications. Results. 21 nails (18 femoral, 2 tibial, 1 humeral) were inserted in 6 adult and 13 paediatric patients. Post-traumatic and congenital/developmental LLD were the most common indications for surgery in the adult and paediatric cohorts respectively. ORDER was employed in 11 cases (9 femurs and 2 tibias). Treatment goals were achieved in all but one case. Complications included superficial infection, locking bolt migration, periprosthetic fracture and component failure. Seven patients required unplanned returns to theatre. Conclusions. The Fitbone nail is an established option for intramedullary limb lengthening, however its use in the UK has been relatively limited compared to the PRECICE until 2021. Our data helps to define its place for limb lengthening and complex deformity correction in both adult and paediatric patients, including in humeral lengthening and retrograde femoral insertion across an open physis. We have identified important potential risks and novel techniques to simplify surgery and avoid complications

Introduction. Motorised intramedullary lengthening nails are considered more expensive than external fixators for limb lengthening. This research aims to compare the cost of femoral lengthening in children using the PRECICE magnetic lengthening nail with external fixation. Materials and Methods. Patients: Retrospective analysis of 50 children who underwent femoral lengthening. One group included patients who were treated with PRECICE lengthening nails, the other group included patients who had lengthening with external fixation. Each group included 25 patients aged between 11–17 years. The patients in both groups were matched for age. Cost analysis was performed following micro-costing and analysis of the used resources during the different phases of the treatments. Results. : Each group's mean patient age was 14.7 years. Lengthening nails were associated with longer operative times compared to external fixators, both for implantation and removal surgery (P-value 0.007 and <0.0001 respectively). Length of stay following the implantation surgery, frequency of radiographs, frequency of outpatient department appointments were all more favourable with lengthening nails. The overall cost of lengthening nails was £1393 more than external fixators, although this difference was not statistically significant (P-value 0.088). Conclusions. The cost of femoral lengthening with lengthening nails was not significantly higher than the external fixators’ cost. Further research to review the effectiveness of the devices and the quality of life during the lengthening process is crucial for robust health economic evaluation

Introduction. The purpose of this research is to compare the quality of life in children during gradual deformity correction using external fixators with intramedullary lengthening nails. Materials and Methods. Prospective analysis of children during lower limb lengthening. Group A included children who had external fixation, patients in group B had lengthening nails. Patients in each group were followed up during their limb reconstruction. CHU-9D and EQ-5DY instruments were used to measure quality of life at fixed intervals. The first assessment was during the distraction phase (1 month postop.), the second was during the early consolidation phase (3 months postop.) and the final one was late consolidation phase (6–9 months depends on the frame time). Results. Group B patients reported significantly better utility compared to Group A. This was observed during all the stages of the treatment. Group B children were less worried (P 0.004), less sad (P 0.0001), less pain (p <0.0001), less tired (P 0.0002), better school work (P0.0041), better sleep (p 0.016), more able to do sports activities (p 0.004) and, they were more independent (p <0.0001) compared to group B. QALYS was better for the nails group compared to external fixation group 0.44 compared to 0.36 for external fixators. Conclusions. Lengthening nails had the potential to improve the quality of life and utility compared to external fixation. This will help further economic evaluation to measure ICER to further explore the cost effectiveness of these devices

Introduction: Limb lengthening using external fixation may be associated with problems such as pin-track infections, poor patient acceptance, muscle transfixation, secondary axial deformity and re-fractures. Intramedullary lengthening nails have been designed to address these issues. Aim: To review the outcomes for femoral limb lengthening in adults managed by intramedullary lengthening nails. Materials and Methods: A retrospective review was undertaken for 8 femoral lengthening procedures performed using intra-medullary lengthening nails over a three-year period. The average age of our patients was 34 years and the average duration of follow up was 26.5 months (Range 8 to 40 months). Either an Albizzia nail (5 femurs) or an ISKD (3 femurs) nail was used for the procedure. Results: Target lengthening was achieved in 7 out of 8 femurs with a average of 38 mm (Range 19 to 70 mm) length gained. The distraction index (length gained per day) was 0.68 on an average and the consolidation index (length of bone consolidating per day) being 0.27 on an average. Premature consolidation in 4 cases, runaway acute lengthening in one patient, prominent metalwork in 4 patients and a bent nail were frequent obstacles and meant multiple visits to theatre. Conclusions: The desired femoral lengthening is achievable using intra-medullary lengthening nails, thereby avoiding problems associated with callostasis using external fixation methods. It is however, important to counsel patients regarding possibilities of significant obstacles and multiple visits to theatre during the process

Introduction and Objectives: Our aim is to analyze results using an Albizzia® gradual lengthening intramedullary nail in the femur. Materials and Methods: From October 1997 to November 2000, 7 femoral lengthenings were performed on 5 patients (2 were bilateral) in our unit, using an intramedullary lengthening nail. Average age was 19 years (15–22). Aetiologies included congenital deformity with symmetric shortening (1 case), fibrous cortical defects (1 case), iatrogenic shortening secondary to trauma (1 case), and 2 cases of symmetric dwarfism (idiopathic drawfism, Turner’s syndrome). Distraction was achieved at 15 cycles/day (1 mm/day). Clinical and radiographic results were evaluated using the Paley criteria, considering the indices of consolidation and distraction. Average follow-up time was 48 months (30–60 months). Results: Average lengthening obtained was 5.7 cm (4–7 cm), with a distraction period of 99 days (45–214 days) and a distraction index of 0.71 mm/day (17 days/1 cm). In bilateral cases, the distraction index was 0.57 mm/day. Consolidation time was 187 days with a consolidation index of 33 days/cm. Complications included 3 mechanical (2 broken screws and one intramedullary saw failure); one involving bone (1 intraoperative fracture), and one case requiring spinal anaesthesia to achieve lengthening in the first few days. No nerve, joint, or infection-related complications were observed. Average duration of surgery was 2 hours 40 minutes. Discussion and Conclusions: The use of a gradual intramedullary lengthening nail yields good results, since it is a more stable system which minimises complications compared to external fixators. It is also a more comfortable procedure for the patient

Introduction. Pixel Value Ratio (PVR) is a radiographic measure of the relative density of the regenerate to the adjacent bone. This has been reported as an objective criterion for regenerate healing and a guide for when to allow full weight bearing (FWB) in lengthening with intramedullary telescopic nails. The threshold for which magnitude of PVR is adequate to allow bearing full weight is not yet agreed. The aim of this study was to identify from our cohort of adult limb lengthening patients the time to FWB following lengthening, the PVR at this point, and how this compared with the recommended values in the literature. Materials and Methods. A retrospective database review identified 30 adult patients treated with the PRECICE femoral nail by two senior authors. Time from completion of lengthening to instruction to fully weight bear was noted. The PVR was calculated for each cortex on plain radiographs taken at each postoperative visit following completion of lengthening. Significance was set at p <0.05. Results. The median age was 30.5 years (IQR 22.5 – 42.5), 19 male and 11 female patients were included. The underlying cause of shortening was post traumatic in 12 (40%) with the remaining due to a wide variety of causes including congenital, infective, and idiopathic leg length discrepancies. Twenty-two nails were antegrade and the mean distance lengthened was 42 mm. Median time from completion of lengthening to full weight bearing was 42 days (IQR 28 – 69). The overall mean PVR at FWB was 0.79. Each surgeon had differing protocols for weightbearing, however there was no statistical difference between time to weight bearing, nor the mean PVR at FWB. There were no implant failures, shortening, or regenerate fractures. Conclusions. We report on our cohort of adult patients treated with intramedullary lengthening nails with a mean PVR of 0.79 at time of full weightbearing. This is considerably lower than the values reported in the literature ranging from 0.90 to 0.93. We therefore suggest that weightbearing following lengthening nails can be permitted earlier than previously reported without an increased risk of complication

Introduction. At Sheffield Children's Hospital, treatment of leg length discrepancy is a common procedure. Historically, this has been done with external fixators. With the development in intramedullary technology, internal nails have become the preferred modality for long bone lengthening in the adolescent population. However, it is important to review whether this technology practically reduces the known challenges seen and if it brings any new issues. Therefore, the aim of this review is to retrospectively evaluate the therapeutic challenges of 16 fit-bone intramedullary femoral lengthening's at Sheffield Children's Hospital between 2021–2022. Materials & Methods. The international classification of function (ICF) framework was used to differentiate outcomes. The patient's therapy notes were retrospectively reviewed for themes around structural, activity and participation limitation. The findings were grouped for analysis and the main themes presented. Results. There were 8 males, mean age 17.4 years (range 17–18) and 8 females, mean age 15.9 years (range 14–18). 5 right and 11 left femurs were lengthened. Underlying pathology varied amongst the 16 patients. All patients went into a hinged knee brace post operatively. Structural limitations included: pain, fixed flexion deformity of the knee, loss of knee flexion, quadriceps muscle lag, muscle spasms and gluteal weakness. The primary activity limitation was reduced weight bearing with altered gait pattern. Participation limitations included reduced school attendance and involvement in activities with peers. Access to Physiotherapy from local services varied dramatically. Five of the cohort have completed treatment. Conclusions. Anecdotally, intramedullary femoral lengthening nails have perceived benefits for families compared to external fixators in the adolescent population. However, there remain musculoskeletal and psychosocial outcomes requiring therapeutic management throughout the lengthening process and beyond. Therefore, quantifying these outcomes is essential for measuring the impact on each patient for comparison. To interpret these themes, we need to evaluate the outcomes objectively, this was not done consistently in this review. Future research should look at outcome measures that are sensitive to all aspects of the ICF. With an aim of improving the therapeutic treatment provided and the overall outcome for the children treated

Objectives. The Precice nail is the latest intramedullary lengthening nail with excellent early outcomes. Implant complications have led to modification of the nail design. The aim of this study was to perform a retrieval study of Precice nails following lower-limb lengthening and to assess macroscopical and microscopical changes to the implants and evaluate differences following design modification, with the aim of identifying potential surgical, implant, and patient risk factors. Methods. A total of 15 nails were retrieved from 13 patients following lower-limb lengthening. Macroscopical and microscopical surface damage to the nails were identified. Further analysis included radiology and micro-CT prior to sectioning. The internal mechanism was then analyzed with scanning electron microscopy and energy dispersive x-ray spectroscopy to identify corrosion. Results. Seven male and three female patients underwent 12 femoral lengthenings. Three female patients underwent tibial lengthening. All patients obtained the desired length with no implant failure. Surface degradation was noted on the telescopic part of every nail design, less on the latest implants. Microscopical analysis confirmed fretting and pitting corrosion. Following sectioning, black debris was noted in all implants. The early designs were found to have fractured actuator pins and the pin and bearings showed evidence of corrosive debris. The latest designs showed evidence of biological deposits suggestive of fluid ingress within the nail but no corrosion. Conclusion. This study confirms less internal corrosion following modification, but evidence of titanium debris remains. We recommend no change to current clinical practice. However, potential reuse of the Precice nail, for secondary limb lengthening in the same patient, should be undertaken with caution. Cite this article: V. C. Panagiotopoulou, K. Davda, H. S. Hothi, J. Henckel, A. Cerquiglini, W. D. Goodier, J. Skinner, A. Hart, P. R. Calder. A retrieval analysis of the Precice intramedullary limb lengthening system. Bone Joint Res 2018;7:476–484. DOI: 10.1302/2046-3758.77.BJR-2017-0359.R1

Introduction. The Precice nail is the latest intramedullary lengthening nail with excellent early outcomes. Implant complications have led to modification of the nail design. The aim of this study was to perform a retrieval study of Precice nails following lower limb lengthening. To assess macroscopic and microscopic changes to the implants and assess differences following design modification, with identification of potential surgical, implant and patient risk factors. Method. 15 nails were retrieved from 13 patients following lower limb lengthening. Macroscopic and microscopic surface damage to the nails were identified. Further analysis included radiology and micro-CT prior to sectioning. The internal mechanism was then analysed with Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy to identify corrosion. Results. 7 male and 3 females underwent 12 femoral lengthenings, 9 antegrade and 3 retrograde. 3 females underwent tibial lengthening. All patients obtained the desired length with no implant failure and full regenerate consolidation. Surface degradation was noted on the telescopic part of every nail design, less on the latest implants. Microscopic analysis confirmed fretting and pitting corrosion. Following sectioning black debris was noted in all implants. The early designs were found to have fractured actuator pins and the pin and bearings had evidence of corrosive debris. The latest designs had evidence of biological deposits suggestive of fluid ingress within the nail. Conclusion. This study suggests fluid ingress occurs with every generation of Precice nail despite modifications. The presence of biological fluid could be an early warning sign of potential corrosion. This in theory could lead to actuator pin fracture and implant failure. The clinical relevance is the potential re-use of a “dormant” nail in patients requiring secondary limb segment lengthening. Retraction of the nail in-situ and re-use for further lengthening requires careful consent for potential implant failure

We present the results of a new non-invasive lengthening nail enabling accurate control of the lengthening process and joint rehabilitation. Introduction. The use of intramedullary lengthening nails have gained popularity as they reduce common complications associated with external fixators, including infection, joint stiffness, bone regenerate deformity, late fracture and patient implant acceptance. Current nails however are associated with complications including implant breakage, mechanical failure, runaway nail and requiring MUA to restart or obtain segment lengthening. The Precice nail incorporates magnet technology with a hand held device allowing non-invasive lengthening. The nail is also reversible allowing shortening if required. Physiotherapy can continue throughout treatment to maintain joint range of motion without concern of uncontrolled nail runaway. The lengthening is axial reducing shear/torsional forces on the regenerate. Method. The lengthening of 4 femora was undertaken in 3 patients, mean age 34 yrs for post-traumatic shortening and short stature. A standard technique included an Ilizarov corticotomy followed by a 6 day latent period. Patients were mobilised partial weight bearing and knee range of motion maintained. The femora were lengthened one third of a millimetre three times per day. Radiographic and clinical review was performed every 2 weeks. Results. The desired femoral length was obtained in all patients, mean 5.6 cms (4.5–6.5). There were no complications of infection, poor bone regenerate or premature consolidation. One patient undergoing bilateral femoral lengthening underwent surgical release of a tight Tensor Fascia Lata following completion of lengthening due to hip flexion contracture. One patient required slowing of the lengthening rate due to knee flexion contracture. Physiotherapy corrected the deformity and the normal lengthening rate could be resumed. Conclusion. The Precice nail is a new device that offers accurate control of the lengthening process and rehabilitation. This should reduce complications of poor regenerate formation and soft tissue contractures

Aims

The aim of this study was to present the first retrieval analysis findings of PRECICE STRYDE intermedullary nails removed from patients, providing useful information in the post-market surveillance of these recently introduced devices.