Aims. Distraction osteogenesis with intramedullary lengthening devices has undergone rapid development in the past decade with implant enhancement. In this first single-centre matched-pair analysis we focus on the comparison of treatment with the PRECICE and STRYDE intramedullary lengthening devices and aim to clarify any clinical and radiological differences. Methods. A single-centre 2:1 matched-pair retrospective analysis of 42 patients treated with the STRYDE and 82 patients treated with the PRECICE nail between May 2013 and November 2020 was conducted. Clinical and lengthening parameters were compared while focusing radiological assessment on osseous alterations related to the nail’s telescopic junction and locking bolts at four different stages. Results. Osteolysis next to the telescopic junction was observed in 31/48 segments (65%) lengthened with the STRYDE nail before implant removal compared to 1/91 segment (1%) in the PRECICE cohort. In the STRYDE cohort, osteolysis initially increased, but decreased or resolved in almost all lengthened segments (86%) after implant removal. Implant failure was observed in 9/48 STRYDE (19%) and in 8/92 PRECICE nails (9%). Breakage of the distal locking bolts was found in 5/48 STRYDE nails (10%) compared to none in the PRECICE cohort. Treatment-associated pain was generally recorded as mild and found in 30/48 patients (63%) and 39/92 (42%) in the STRYDE and PRECICE cohorts, respectively. Temporary range of motion (ROM) limitations under distraction were registered in 17/48 (35%) segments treated with the STRYDE and 35/92 segments (38%) treated with the PRECICE nail. Conclusion. Osteolysis and periosteal reaction, implant breakage, and pain during lengthening and consolidation is more likely in patients treated with the STRYDE nail compared to the PRECICE nail. Temporary ROM limitations during lengthening occurred independent of the applied device. Implant-related osseous alterations seem to remodel after implant removal. Cite this article: Bone Joint J 2023;105-B(1):88–96

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

Aims. The Precice intramedullary limb-lengthening system has demonstrated significant benefits over external fixation lengthening methods, leading to a paradigm shift in limb lengthening. This study compares outcomes following antegrade and retrograde femoral lengthening in both adolescent and adult patients. Patients and Methods. A retrospective review of prospectively collected data was undertaken of a consecutive series of 107 femoral lengthening operations in 92 patients. In total, 73 antegrade nails and 34 retrograde nails were inserted. Outcome was assessed by the regenerate healing index (HI), hip and knee range of movement (ROM), and the presence of any complications. Results. The mean lengthening was 4.65 cm (1.5 to 8) in the antegrade group and 4.64 cm (1.6 to 8) in the retrograde group. Of the 107 lengthenings, 100 had sufficient datapoints to calculate the mean HI. This was 31.6 days/cm (15 to 108). There was a trend toward a lower (better) HI with an antegrade nail and better outcomes in adolescent patients, but these were not statistically significant. Hip and knee ROM was maintained and/or improved following commencement of femoral lengthening in 44 patients (60%) of antegrade nails and 13 patients (38%) of retrograde nails. In female patients, loss of movement occurred both earlier and following less total length achieved. Minor implant complications included locking bolt migration and in one patient deformity of the nail, but no implant failed to lengthen and there were no deep infections. Three patients had delayed union, five patients required surgical intervention for joint contracture. Conclusion. This study confirms excellent results in femoral lengthening with antegrade and retrograde Precice nails. There is a trend for better healing and less restriction in hip and knee movement following antegrade nails. There are clinical scenarios, that mandate the use of a retrograde nail. However, when these are not present, we recommend the use of antegrade nailing. Cite this article: Bone Joint J 2019;101-B:1168–1176

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

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

Limb length deficiency, secondary to trauma or infection, is a common reason for referral to our tertiary service. After experiencing troubles with the Intramedullary Skeletal Kinetic Distractor (ISKD), we changed implant to the magnet operated Precice nail. We evaluated the safety and reliability of this novel device and compared it to our early ISKD results. To minimise variables, we selected femurs only. In total, we reviewed medical and radiographic records of 20 cases (8 ISKD, 12 Precise) from 2010–2015. At each postoperative visit, the accuracy and precision of distraction and complications were recorded. Accuracy reflected how close the measured lengthening was to the prescribed distraction at each postoperative visit. Precision reflected how close the repeated measurements were to each other over the course of total lengthening period. No patients were lost to follow-up (1–3.5 years). With the Precice nail (2012–2015), 11/12 were male and 10/12 were caused by trauma. The mean age was 34. Mean total lengthening was 38mm (range, 29–53mm), with an accuracy of 98percnt; and precision of 92percnt;. All patients achieved target lengthening at a rate of 1mm lengthening per day. In one case, the Precice nail fractured and this was revised successfully. With the ISKD group (2010–2012), 8/8 had complications (magnet jamming, nail breakage, equinus contractures and claw toes), with 25percnt; achieving accurate lengthening and precision of 38percnt;. Our results so far have justified our change in implant choice and, in our experience, support the Precice nail as being safe and precise

Introduction. We have previously published limb lengthening using external fixation in pathological bone diseases. We would like to report a case series of femoral lengthening using the PRECICE system in a similar pathological group especially looking at it's feasibility and complications. Materials and Methods. This is a case series of four patients, two patients with osteogenesis imperfecta and two with Ollier's disease, who underwent femoral lengthening via distraction osteogenesis using the PRECICE intramedullary nail system. It was a retrospective study from a prospective database from clinical records and radiographs. Results. The mean age at the time of surgery was 15.5 years, the mean preoperative leg length discrepancy was 30mm, and the mean distraction distance achieved was 28.75mm. Since these patients were of shorter heigh, limb lengthening was considered. All 4 patients had successful insertion of the nail. The outcomes noted from the 4 patients are collated, with several complications occurring including delayed femoral union, fixed flexion deformity of the hip, persisting pain and quadriceps weakness. Those with Ollier's disease underwent an increased rate of distraction to prevent premature healing. The implications of long-term bisphosphonate therapy in OI are discussed with regards to the risk of delayed femoral union and intra-operative fracture. Conclusions. Intramedullary femoral lengthening in pathological bone disease is possible, but the surgeon needs to give attention to certain details. The regenerate formation is based on the background pathology irrespective of the hardware used. There is much more compliance with the nail technique

Background:. External fixators are not as well tolerated around the femur when compared to the tibia. Lengthening with an intramedullary device is therefore attractive. Method:. We reviewed all cases of femoral lengthening performed at our unit from 2007 to 2014. Cases of non-unions, concurrent deformities, congenital limb deficiencies and lengthening with an unstable hip were excluded. This left 33 cases for review. Healing index, implant tolerance and complications were compared. Results and Discussion:. In 20 cases the Precice lengthening nail was used and in 13 cases the LRS external fixator system. The desired length was achieved in all cases in the Precice group and in 12 of 13 cases in the LRS group. The Precice group had a more rapid return to full weight bearing. The mean healing index was 31.3 days/cm in the Precice and 47.1 days/cm in the LRS group. There was an increased incidence of complications with LRS lengthening, including pin site infections and regenerate deformity. Implant tolerance and the patients' perception of the cosmetic result were better with the Precice treatment. Conclusion:. We conclude excellent functional results with fewer complications and greater patient satisfaction in femoral lengthening with a Precice intramedullary nail

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. Limb-lengthening nails have largely replaced external fixation in limb-lengthening and reconstructive surgery. However, the adverse events and high prevalence of radiological changes recently noted with the STRYDE lengthening nail have raised concerns about the use of internal lengthening nails. The aim of this study was to compare the prevalence of radiological bone abnormalities between STRYDE, PRECICE, and FITBONE nails prior to nail removal. Methods. This was a retrospective case series from three centres. Patients were included if they had either of the three limb-lengthening nails (STYDE, PRECICE, or FITBONE) removed. Standard orthogonal radiographs immediately prior to nail removal were examined for bone abnormalities at the junction of the telescoping nail parts. Results. In total, 306 patients (168 male, 138 female) had 366 limb-lengthening nails removed. The mean time from nail insertion to radiological evaluation was 434 days (36 to 3,015). Overall, 77% of STRYDE nails (20/26) had bone abnormalities at the interface compared with only 2% of FITBONE (4/242) and 1% of PRECICE nails (1/98; p < 0.001). Focal osteolysis in conjunction with periosteal reaction at the telescoping interface was only observed in STRYDE nails. Conclusion. Bone abnormalities at the interface of telescoping nail parts were seen in the majority of STRYDE nails, but only very rarely with FITBONE or PRECICE nails. We conclude that the low prevalence of radiological changes at the junctional interface of 242 FITBONE and 98 PRECICE nails at the time of nail removal does not warrant clinical concerns. Cite this article: Bone Joint J 2021;103-B(11):1731–1735

Introduction. There is no doubt that the future of limb lengthening lies with internal lengthening. Complication rates are reduced and patient satisfaction is increased. The evolution of internal lengthening peaked with the dual direction, easily inserted and externally controlled PRECICE Nail. It has excelled in performance in accuracy and satisfaction. Its versatility increased with smaller sizes and increased excursion. A field safety notice was issued was issued in October 2021 by the parent company NuVasive. The advice was monitoring of current cases and a hold on implantation until after a review of process. At the National Orthopaedic Hospital Cappagh we elected to remove all implanted nails and assess the nail integrity and physiological changes associated with implantation. Materials & Methods. All patients in who a retained Precice nail at the time of the field safety notice were identified. Patients and families were contacted to explain the issued safety notice from the company and explain that we would be scheduling them for nail removal. This was part of our standard care but we prioritised this group on our waiting list. Consent was obtained for nail removal but also for histological assessment of canal scrapings, blood ion level analysis and independent assessment of the retrieved nail by our academic collaborators at University College Dublin. Ion levels were then repeated at an interval post removal with consent. Results. We identified 7 Precice nails in 5 patients still implanted. All patients had consolidated after lengthening and were ready for nail removal. Elevated Titanium blood ion levels were identified at the time of retrieval. Histological abnormalities consistent with metalosis were identified. In all cases the nail was grossly intact and examination of the motor showed no evidence of wear or failure. Follow up ion levels obtained post retrieval showed persistent elevation. Conclusions. Our retrieval audit shows persistent elevation of Titanium ion levels and abnormal histology despite apparent nail integrity. These findings require further evaluation in a larger retrieval series to determine if there is a high incidence of this phenomenon and if ion levels have a clinical effect

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

Aims. The STRYDE nail is an evolution of the PRECICE Intramedullary Limb Lengthening System, with unique features regarding its composition. It is designed for load bearing throughout treatment in order to improve patient experience and outcomes and allow for simultaneous bilateral lower limb lengthening. The literature published to date is limited regarding outcomes and potential problems. We report on our early experience and raise awareness for the potential of adverse effects from this device. Methods. This is a retrospective review of prospective data collected on all patients treated in our institution using this implant. We report the demographics, nail accuracy, reliability, consolidation index, and cases where concerning clinical and radiological findings were encountered. There were 14 STRYDE nails implanted in nine patients (three male and six female) between June 2019 and September 2020. Mean age at surgery was 33 years (14 to 65). Five patients underwent bilateral lengthening (two femoral and three tibial) and four patients unilateral femoral lengthening for multiple aetiologies. Results. At the time of reporting, eight patients (13 implants) had completed lengthening. Osteolysis and periosteal reaction at the junction of the telescopic nail was evident in nine implants. Five patients experienced localized pain and swelling. Macroscopic appearances following retrieval were consistent with corrosion at the telescopic junction. Tissue histology was consistent with effects of focal metallic wear debris. Conclusion. From our early experience with this implant we have found the process of lengthening to be accurate and reliable with good regenerate formation and consolidation. Proposed advantages of early load bearing and the ability for bilateral lengthening are promising. We have, however, encountered concerning clinical and radiological findings in several patients. We have elected to discontinue its use to allow further investigation into the retrieved implants and patient outcomes from users internationally. Cite this article: Bone Joint J 2021;103-B(6):1168–1172

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. Methods. We collected ten nails removed from six patients, together with patient clinical data and plain radiograph imaging. We performed macro- and microscopic analysis of all surfaces and graded the presence of corrosion using validated semiquantitative scoring methods. We determined the elemental composition of surface debris using energy dispersive x-ray spectroscopy (EDS) and used metrology analysis to characterize the surface adjacent to the extendable junctions. Results. All nails were removed at the end of treatment, having achieved their intended lengthening (20 mm to 65 mm) and after regenerate consolidation. All nails had evidence of corrosion localized to the screw holes and the extendable junctions; corrosion was graded as moderate at the junction of one nail and severe at the junctions of five nails. EDS analysis showed surface deposits to be chromium rich. Plain radiographs showed cortical thickening and osteolysis around the junction of six nails, corresponding to the same nails with moderate – severe junction corrosion. Conclusion. We found, in fully united bones, evidence of cortical thickening and osteolysis that appeared to be associated with corrosion at the extendable junction; when corrosion was present, cortical thickening was adjacent to this junction. Further work, with greater numbers of retrievals, is required to fully understand this association between corrosion and bony changes, and the influencing surgeon, implant, and patient factors involved. Cite this article: Bone Jt Open 2021;2(8):599–610

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. Intramedullary lengthening devices have been in use in older children with closed /open growth plates with good success. This study aims to present the early experience of the FITBONE nail since withdrawal of the PRECICE nail. Materials & Methods. Retrospective analysis of both antegrade and retrograde techniques were utilized. Only patients where union was achieved and full weight bearing commenced were included. The complication rate, length gained, distraction index, weight bearing index (WBI) as well as mechanical axes were analysed. Results. 14 (7 males, 7 females) of a total of 16 (7 males, 7 females) patients with a mean age of 16.9 years with varied diagnosis of LLD were analysed. The mean length gained was 38 mm with an average distraction index of 0,74 mm/day. WBI in these patients on average was 59,6 days/cm lengthened. 6 complications were observed, including two nonunions (successfully treated) and a knee subluxation. Mechanical axis deviation improved from 13,3 mm to 6 mm on average. Overall there has been a nonsignificant tendency for WBI to decrease (Spearman's rank correlation coefficient −0.47, p=0.08) with increasing number of cases done, while no correlation between length gained and WBI (−0.01, p=0.96, respectively) was observed. Some nuances will be discussed. Conclusions. Limb lengthening with the FITBONE nail is relatively safe and efficient, however no significant change was seen in the outcome with previous motorized nails

Introduction. The FitBone lengthening nail (Orthofix UK) is an intramedullary device licensed for the lengthening of long bones in adults in the UK. It contains a motor powered by electricity transmitted via an induction coil placed underneath the skin. It was developed in Germany two decades ago but uptake in the UK has only started more recently. The aim of this study was to review the first cohort of FitBone lengthening nails in a unit with significant experience of other lengthening nails (including PRECICE and Stryde). Materials & Methods. Demographic, clinical and radiological data was prospectively collected on all FitBone cases starting in February 2022. Accuracy of lengthening rate, patient satisfaction and implant issues were all considered. Complications and learning points were recorded and discussed by the multidisciplinary team involved in the patients care. Results. Eleven lengthening nails were inserted between February and November 2022 (6 right femurs, 5 left femurs). The average patient age was 31 (16–57) with 4 females and 7 males. The average lengthening achieved was 44mm (13– 70) over an average of 59 days (35 to 104). Significant technical issues were encountered in this cohort of patients including slow opening up at osteotomy site (3 requiring speeding up of programme), early consolidation (one requiring re-do osteotomy) and backing out of locking screws (3 out of 11 nails). There were also patient use concerns with difficulty using the motor and the inability to reverse the lengthening without an additional component to the motor. Conclusions. We present the first UK cohort of patients with femoral lengthening using the FitBone implant and device. We highlight the technical and patient issues encountered during this learning curve and propose solutions to avoid these pitfalls

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

Introduction. The STRYDE nail is an evolution of the PRECICE Intramedullary Limb Lengthening System, with unique features regarding its composition. It is designed for load bearing throughout treatment in order to improve patient experience and outcomes and allow for simultaneous bilateral lower limb lengthening. The literature published to date is limited with regards to both outcomes and potential issues. In this paper we report on our early experience and raise awareness for the potential of adverse effects from this device. Materials and Methods. This is a review of all patients treated in our institution using this implant. Data were prospectively recorded. We report on demographics, nail accuracy, reliability, consolidation index and cases where concerning clinical and radiological findings were encountered. Results. 14 Stryde nails were implanted in nine patients (three males and six females) between June 2019 and September 2020. Mean age at surgery was 33 years old (14–65 years old). Five patients underwent bilateral lengthening (two femoral and three tibial) and four patients unilateral femoral lengthening for multiple aetiologies. By the time of this report eight patients (13 implants) had completed lengthening. Osteolysis and periosteal reaction at the junction of the telescopic nail was evident in nine implants. Five patients experienced localised pain and swelling. Macroscopic appearances following retrieval were consistent with corrosion at the telescopic junction. Tissue histology was consistent with effects of focal metallic wear debris. Conclusions. From our early experience with this implant we have found the process of lengthening to be accurate and reliable with good regenerate formation and consolidation. Proposed advantages of early load bearing and the ability for bilateral lengthening are promising. We have, however, encountered cases with concerning clinical and radiological findings. We have elected to discontinue its use to allow further investigation into the retrieved implants and patient outcomes from users internationally

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