Tibial Bone Loss Research Articles

Extent of posterolateral tibial plateau impaction fracture correlates with anterolateral complex injury and has an impact on functional outcome after ACL reconstruction

PurposeThe impact of posterolateral tibial plateau impaction fractures (TPIF) on posttraumatic knee stability in the setting of primary anterior cruciate ligament (ACL) tear is unknown. The main objective was to determine whether increased bone loss of the posterolateral tibial plateau is associated with residual rotational instability and impaired functional outcome after ACL reconstruction.MethodsA cohort was identified in a prospective enrolled study of patients suffering acute ACL injury who underwent preoperative standard radiographic diagnostics and clinical evaluation. Patients were included when scheduled for isolated single-bundle hamstring autograft ACL reconstruction. Exclusion criteria were concurrent anterolateral complex (ALC) reconstruction (anterolateral tenodesis), previous surgery or symptoms in the affected knee, partial ACL tear, multi-ligament injury with an indication for additional surgical intervention, and extensive cartilage wear. On MRI, bony (TPIF, tibial plateau, and femoral condyle morphology) and ligament status (ALC, concomitant collateral ligament, and meniscus injuries) were assessed by a musculoskeletal radiologist. Clinical evaluation consisted of KT-1000, pivot-shift, and Lachman testing, as well as Tegner activity and IKDC scores.ResultsFifty-eight patients were included with a minimum follow-up of 12 months. TPIF was identified in 85% of ACL injuries (n = 49). The ALC was found to be injured in 31 of 58 (53.4%) cases. Pearson analysis showed a positive correlation between TPIF and the degree of concomitant ALC injury (p < 0.001). Multiple regression analysis revealed an increased association of high-grade TPIF with increased lateral tibial convexity (p = 0.010). The high-grade TPIF group showed worse postoperative Tegner scores 12 months postoperatively (p = 0.035).ConclusionHigher degrees of TPIFs are suggestive of a combined ACL/ALC injury. Moreover, patients with increased posterolateral tibial plateau bone loss showed lower Tegner activity scores 12 months after ACL reconstruction.Level of evidenceIII.

How metal augments, polyethylene thickness and stem length affect tibial baseplate load transfer in revision total knee arthroplasty

BackgroundIt is unclear howmetal augments,polyethylene (PE) liner thickness, and length of cemented stemcontribute to load transferwhen reconstructing uncontained tibial metaphyseal bone loss of Anderson Orthopedic Research Institute (AORI) Type II defects during revision total knee arthroplasty (rTKA).The aimof this study is to understand the impact of these three variableson load transfer through the tibial baseplate. For a fixed defect depth, we hypothesized that there is a particular combination of liner and augment thickness and stem length that minimizes bone stress, reducing the risk of aseptic loosening. MethodsWe conducted a finite element analysis (FEA) to model stresses at the bone-cement interface with different iterations of metal augments, PE liner thicknesses andfully-cemented stems lengths. ResultsFor a 20 mm tibial defect, constructs with thicker metal augments and thinner polyethylene liners were superior. Constructswith a fully cemented stem further reduced bone stress on the tibial plateau. Bone stress was lowest when a 100 mm fully-cemented stem was used, while stems between 30 mm – 80 mm produced similar results. ConclusionsWhen addressing a tibial bone defect of AORI Type II in rTKA, our FEA model demonstrates that surgeons should opt to use the thickest metal augments in combination with afully-cemented stem with an added length of at least 30 mm, which allows for surgical flexibility together with the most stable construct.Our study is notably limited by lack of modeling of knee joint moments, which are important when considering micromotion, bone-implant interface and stem effectiveness.

Custom-Made Implants in Ankle Bone Loss: A Retrospective Assessment of Reconstruction/Arthrodesis in Sequelae of Septic Non-Union of the Tibial Pilon.

Background and Objectives: Treating segmental tibial and ankle bone loss after radical surgery for chronic osteomyelitis is one of the most challenging problems encountered by orthopaedic surgeons. Open tibia and ankle fractures occur with an incidence of 3.4 per 100,000 and 1.6 per 100,000, respectively, and there is a high propensity of developing fracture-related infection with associated chronic osteomyelitis in patients. Segmental tibial and ankle bone loss have recently received new and improved treatments. Materials and Methods: Above all, 3D printing allows for the customization of implants based on the anatomy of each patient, using a personalized process through the layer-by-layer deposition of materials. Results: This article presents different cases from the authors' experience. Specifically, four patients suffered tibia and ankle fractures and after radical surgery for chronic osteomyelitis combined with high-performance antibiotic therapy underwent ankle reconstruction/arthrodesis with custom-made tibial spacers. Conclusions: Thanks to 3D-printed patient-specific devices, it is possible to perform surgical procedures that, for anatomical reasons, would have been impossible otherwise. Moreover, an improvement in overall functionality and an important reduction in pain were shown in the last follow-up in all patients.

Mechanical Alignment in Total Knee Arthroplasty for Varus Knee Osteoarthritis Leads to Significant Tibial Bone Loss.

Background Obtaining a neutral postoperative alignment is said to be a guiding principle for performing a successful total knee arthroplasty (TKA). There are many different alignment philosophies and surgical techniques to attain the goal of proper alignment. This study aimed to radiologically measure the difference in the amount of tibial bony resection required to perform a mechanical alignment versus an anatomic alignment TKA. Methods Two observers retrospectively reviewed the long leg radiographs of 100 patients (61 females and 39 males) listed for TKA between 2015 and 2018, measuring the amount of tibial bony resection required to achieve mechanical or anatomic alignment TKA. Results These radiographs' overall lower limb mechanical axis ranged between 16° varus and 17.6° valgus (mean 4.4° varus, standard deviation (SD) 6.64). By referencing 4 mm from the worn side, the mean resection needed from the normal side of the tibial plateau is 7.6 mm in the mechanical alignment measurement and 5.2 mm in the anatomical alignment measurement (p<0.0001). Therefore, 17% of mechanical alignment cuts require a tibial cut of more than 10 mm (mean 12.382 mm). No anatomical alignment measurements exceed 10 mm. When a virtual tibial cut >10 mm is required, the medial proximal tibial angle (MPTA) is a stronger predictor of deformity than the mechanical axis. Conclusion This radiological study shows that an anatomical alignment tibial cut is more bone conserving on the tibia than a mechanical alignment tibial cut and may lead to less asymmetry of the bony cuts and greater bony preservation, but clinical correlation is needed.

The Incidence of Posterolateral Tibial Plateau and Central Lateral Femoral Condylar Impaction Fractures in a Pediatric and Young Adult Population.

Posterolateral tibial plateau and central lateral femoral condylar impaction fractures are known to occur in the setting of anterior cruciate ligament (ACL) tears. There have been no prior investigations into the incidence and morphology of posterolateral tibial plateau impaction fractures in the setting of ACL injury in a pediatric population. Patients between 9 and 22 years of age with knee magnetic resonance imagings (MRIs) performed demonstrating complete or partial ACL tear were included in this study. MRI reports were reviewed to denote the presence of posterior cruciate ligament, medial collateral ligament, or lateral collateral ligament injury, meniscus tears, cartilage lesions. MRIs were reviewed by 2 fellowship-trained orthopaedic surgeons to denote the presence of posterolateral tibial plateau and central lateral femoral condylar impaction fractures and physeal status of femoral and tibial physes. Statistical analysis performed included χ 2 analysis and the Student t testing. A total of 328 patients with a primary ACL tear were identified. The mean age of patients included was 16.5 years (range: 9.0-21.5). The incidence of posterolateral tibial plateau impaction fractures was 83/328 (25.3%) while the incidence of lateral femoral condylar impaction fractures was 119/328 (36.3%). Bipolar impaction fractures occurred in 37/328 (11.3%). Of the 83 tibial impaction fractures identified, 82 were low-grade morphologic subtypes. Patients with lateral tibial plateau impaction fractures were older than those with no fracture (17.2±2.2 vs. 16.3±2.1, P =0.001). Only 3/38 (7.9%) patients with an open tibial physis sustained a tibial plateau impaction fracture compared with 80/290 (27.6%) with a closed tibial physis (χ 2 value: 6.9, P =0.009). There was no difference in proportion of patients with lateral femoral condylar impaction fractures based on femoral physeal status ( P =0.484). The incidence of posterolateral tibial plateau impaction fractures in the setting of ACL tear in a pediatric and young adult patient population appears to be lower while lateral femoral condylar impaction fractures occur more frequently when comparing to previously reported incidences found in adult populations in the literature. Furthermore, posterolateral tibial plateau impaction fractures occur less frequently in those with an open proximal tibial physis and high-grade posterolateral tibial plateau bone loss is exceedingly rare in pediatric and young adult patients. Lateral femoral condylar impaction fractures are associated with lateral meniscal tears and medial meniscal ramp lesions. Level IV-cross-sectional study.

Bone defect classifications in revision total knee arthroplasty, their reliability and utility: a systematic review.

There are various classification systems described in the literature for managing bone defects in revision knee arthroplasty (RTKA). We analysed the reliability and usefulness of these classification systems. (1) To review and critique the various classification systems proposed for bone loss in RTKA. (2) Among all the proposed classifications which one is the most commonly used by surgeons to report their results. (3) What is the reliability of various bone defect classification systems for RTKA. In this review, we have assessed the studies validating those classifications with a detailed description of the limitations and the proposed modifications. This systematic review was conducted following PRISMA guidelines. Pubmed/Medline, CINAHL, EMBASE, Scopus, Cochrane databases and Web of Science databases were searched using multiple search terms and MeSH terms where possible. Studies meeting inclusion criteria were assessed for statistical parameters of reliability of a classification system. We found 16 classification systems for bone defects in RTKA. Six studies were found evaluating a classification system with reporting their reliability parameters. Fifty-four studies were found which classified bone loss using AORI classification in their series. AORI classification is most commonly reported for classifying bone defects. Type T2B and F2B are the most common bone defects in RTKA. The average kappa value for AORI classification for femoral bone loss was 0.38 (0.27-0.50) and 0.76 (0.63-1) for tibial bone loss assessment. None of the available classification systems is reliably established in determining the bone loss and treatment plans in RTKA. Among all, AORI classification is the most widely used system in clinical practice. The reliability of AORI Classification is fair for femoral bone loss and substantial for tibial bone loss.

Activation of Focal Adhesion Kinase Restores Simulated Microgravity-Induced Inhibition of Osteoblast Differentiation via Wnt/Β-Catenin Pathway.

Simulated microgravity (SMG) inhibits osteoblast differentiation (OBD) and induces bone loss via the inhibition of the Wnt/β-catenin pathway. However, the mechanism by which SMG alters the Wnt/β-catenin pathway is unknown. We previously demonstrated that SMG altered the focal adhesion kinase (FAK)-regulated mTORC1, AMPK and ERK1/2 pathways, leading to the inhibition of tumor cell proliferation/metastasis and promoting cell apoptosis. To examine whether FAK similarly mediates SMG-dependent changes to Wnt/β-catenin in osteoblasts, we characterized mouse MC3T3-E1 cells cultured under clinostat-modeled SMG (µg) conditions. Compared to cells cultured under ground (1 g) conditions, SMG reduces focal adhesions, alters cytoskeleton structures, and down-regulates FAK, Wnt/β-catenin and Wnt/β-catenin-regulated molecules. Consequently, protein-2 (BMP2), type-1 collagen (COL1), alkaline-phosphatase activity and matrix mineralization are all inhibited. In the mouse hindlimb unloading (HU) model, SMG-affected tibial trabecular bone loss is significantly reduced, according to histological and micro-computed tomography analyses. Interestingly, the FAK activator, cytotoxic necrotizing factor-1 (CNF1), significantly suppresses all of the SMG-induced alterations in MC3T3-E1 cells and the HU model. Therefore, our data demonstrate the critical role of FAK in the SMG-induced inhibition of OBD and bone loss via the Wnt/β-catenin pathway, offering FAK signaling as a new therapeutic target not only for astronauts at risk of OBD inhibition and bone loss, but also osteoporotic patients.

Total Knee Replacement with an Uncemented Porous Tantalum Tibia Component: A Failure Analysis.

Porous tantalum has been extensively used in orthopaedic surgery, including uncemented total knee arthroplasty (TKA). Favourable results were reported with earlier monobloc tibial components and the design evolved to modular implants. We aimed to analyse possible causes for extensive medial tibia bone loss, resulting in modular porous tantalum tibia baseplate fracture after primary TKA. Retrieved tissue samples were scanned with 3 MeV focused proton beam for Proton-Induced X-ray Emission (micro-PIXE) elemental analysis. Fractographic and microstructural analysis were performed by stereomicroscopy. A full 3D finite-element model was made for numerical analysis of stress–strain conditions of the tibial baseplate. Histological examination of tissue underneath the broken part of the tibial baseplate revealed dark-stained metal debris, which was confirmed by micro-PIXE to consist of tantalum and titanium. Fractographic analysis and tensile testing showed that the failure of the tibial baseplate fulfilled the criteria of a typical fatigue fracture. Microstructural analysis of the contact surface revealed signs of bone ingrowth in 22.5% of the surface only and was even less pronounced in the medial half of the tibial baseplate. Further studies are needed to confirm the responsibility of metal debris for an increased bone absorption leading to catastrophic tibial tray failure.

The use of tantalum cones and diaphyseal-engaging stems in tibial component revision: a consecutive series

IntroductionRevision knee arthroplasty presents a number of challenges, including management of bone loss. The goal in managing moderate to large bone defects is fixation that is sufficient enough to allow early weight-bearing. The purpose of this study was to describe the surgical technique and clinical and radiographic outcomes of patients treated with porous tantalum metaphyseal cones in combination with long uncemented diaphyseal-engaging stems to manage tibial bone loss in revision total knee arthroplasty (TKA).Materials and methodsThirty-six aseptic revision TKAs were performed at our institution between 2016 and 2019 by two senior authors. A single trabecular metal tantalum cone combined with a long (100 or 155 mm) press fit, diaphyseal-engaging stem was used in all cases to reconstruct metaphyseal bone defects and to augment tibial fixation. Cemented stems were excluded. The tibiofemoral angle was measured along the tibial and femoral shaft axes on the weight-bearing anteroposterior radiograph at final follow-up (range 15–56 months). All clinical and surgical complications, reoperations, and revisions of any component were recorded. Survivorship free of revision was evaluated at the time of the latest follow-up.ResultsThe mean Knee Society Score (KSS) and Knee Society Function Score (KSS-F) improved significantly from 29.7 points preoperatively (range 11–54 points) to 86 points (range 43–99 points) and from 20.4 points preoperatively (range 0–55 points) to 72.3 points (range 30–90 points) (p < 0.05), respectively. Eleven tibial constructs (30.5%) had incomplete, nonprogressive radiolucent lines (≤ 2 mm). All tibial cones demonstrated osteointegration. One patient underwent a full revision for periprosthetic joint infection, and survivorship free of any component revision was 91.7% at final follow-up.ConclusionsHybrid fixation with uncemented diaphyseal-engaging stems and porous tantalum metaphyseal cones resulted in radiographic lack of osteolysis, good clinical outcomes, and survivorship of 91.7% at a median follow-up of 33 months when considering all-cause revision as the endpoint.

Radiographic Comparative Analysis on Medial Tibial Bone Loss for Fixed Bearing Unicompartmental Knee Arthroplasty and Total Knee Arthroplasty at 3 Year Period

Radiographic Comparative Analysis on Medial Tibial Bone Loss for Fixed Bearing Unicompartmental Knee Arthroplasty and Total Knee Arthroplasty at 3 Year Period

Management of Segmental Tibial Bone Defects With a Motorized Intramedullary Bone Transport Nail: A Case Review With Follow-Up

Large segment bone defects of the tibia are challenging problems. Although caused by a wide range of conditions, tibial critical bone loss defects often require complex reconstructive plans with prolonged inability to weight-bear on the effected extremity. Reconstruction options frequently require harvesting of autograft leading to further morbidity. Distraction osteogenesis allows reconstruction of large segmental defects of the tibia while avoiding donor site morbidity. Historically, distraction osteogenesis of tibia was most reliably performed with circler ring external fixation. This process allowed early weight-bearing but unfortunately has considerable drawbacks. Negative effects include pin tract irritation and inability to wear normal clothes. The advent of the bone transport nail now allows management of tibial critical bone loss defects through distraction osteogenesis negating the need for external fixation. This new technique allows treatment of large segmental tibial defects by means of distraction osteogenesis with an all-internal device avoiding the negative effects of external fixation while simultaneously allowing early weight-bearing.

Proximal tibial bone loss in the first 2 years after unicondylar knee arthroplasty: Anatomical pattern, predictors and clinical correlation

BackgroundTibial stress fracture, anteromedial bone pain, and early subsidence could occur after unicondylar knee arthroplasty (UKA). The change in metaphyseal tibial bone density (MTBD) in the coronal and sagittal planes after UKA might be a contributing factor, but this has rarely been investigated. The aim of this study was to assess the regional and temporal change in MTBD in the coronal and sagittal planes in the first 2 years after UKA. MethodsPatients with fixed-bearing medial UKA were recruited. The change in MTBD in the first 24 months after UKA using digital radiological densitometry (DRD) was measured. Potential predictors and clinical correlations were analyzed. ResultsEighty-four cases (female 60%) were selected for review. The follow up time was 63 (±17) months. Anterior and medial regions had the largest proportion of cases with MTBD reduction (90–97%, P < 0.05). Reduction was largest at anterior and medial regions (21–29%, P < 0.05) and smallest at posterior and lateral regions (5–15%, P < 0.05). Maximal reduction occurred at 12 months for the medial region and 24 months for the anterior region. MTBDs of both regions were not significantly influenced by any confounding factors. Significant correlation was found between medial MTBD and Function Score at 6 months. ConclusionsBone loss in a zonal pattern occurs in the first 2 years after UKA with the largest loss in the anterior region below the tibial tray. It is not affected by body mass index, perioperative alignment, or angle of correction. This suggests a physiological response to trauma other than a mechanical response to the change in bone strain.

The Use of Metaphyseal Cones and Sleeves in Revision Total Knee Arthroplasty.

The burden of revision total knee arthroplasty (rTKA) is expected to increase with the rise in the number of TKA procedures being performed yearly. Management of bone loss during rTKA is challenging and necessitates appropriate surgical planning. Metaphyseal cones and sleeves have emerged as an increasing popular option for addressing metaphyseal femoral and tibial bone loss when performing rTKA. Understanding what cones and sleeves are commercially available and when to use them are critical parts of preoperative evaluation and planning. The purpose of this comprehensive review was to present different design philosophies, types of manufacturing, clinical outcomes, and the versatility and interchangeability of varying cones and sleeves with different TKA revision systems.

Custom-made endofemoral sleeves in knee revision surgery: case report and technical notes

Revision total knee arthroplasty is a challenging procedure for every orthopaedic surgeon, especially when a megaprosthesis is involved. Possible surgical solutions in case of distal femur megaprosthesis revision are total femoral replacement (TFR) or amputation/disarticulation. TFR is affected by an extremely high rate of complications, while amputation/ disarticulation leads to unacceptable functional results. We report the case of a 59-year-old woman who underwent a staged left knee megaprosthesis revision for infection with massive femoral and tibial bone loss and complete disruption of extensor mechanism following 7 prior surgeries. To manage these problems, we developed a new, custom porous titanium endofemoral sleeve for the femoral side and a custom porous titanium cone for tibial reconstruction that were tailored to the patient’s specific bone loss and matched with the tumor prosthetic design used. A custom-made endofemoral sleeve may be a viable solution introducing an intermediate step between distal femur megaprosthesis and total femur substitution. Accurate and detailed surgical planning as well as intraoperative management of soft tissues and residual bone stock are key factors for optimal outcomes.

Utility of Ipsilateral Medial Fibular Transport Using the Ilizarov Frame in the Treatment for Non-elderly Patients Sustaining Massive Tibial Bone Defects as a Sequela of Trauma and Infection: A Systematic Review

Introduction and Objectives. Segmental tibial bone loss from tumor, trauma, or infection is a debilitating, limb-threatening scenario where treatment principles involve aggressive resection of infected tissues usually leading to large defects requiring reconstruction. A systematic review was conducted to determine the best available evidence related to the ipsilateral medial fibular transport using the Ilizarov frame in the management of these massive tibial bone defects.&#x0D; Methods. Multiple medical online database search for articles containing the keywords: ipsilateral medial fibular transport, medial fibula transport, medialization of the fibula using the Ilizarov fixator, ring external fixator, vascularized free fibula, vascularized fibula transfer, and other related MeSH terms was done. Data was summarized to describethe mean age, bone defect, external fixator time, external fixator index, and bone and functional results using the ASAMI criteria.&#x0D; Results. Eight studies with a total of 43 patients with massive tibial bone defects treated by fibular transport using the Ilizarov methods were identified. The mean age was 25.27 years (6.5-44.4) with a mean bone defect of 13.57 cm (9.52-17). The mean length of follow-up was 37.67 months (18-70.2). The bone union rate was 100%. Mean external fixation time was 9.59 months (8.31-10.88) and external fixation index was 0.61 months/cm (0.52-0.70). The majority of patients have an excellent bone (84%) and functional (52%) results. The average rate of complication was determined at 0.74/patient (95% CI, 0.60-0.89). The most common complications include pin-tract infection (37%), residual loss of motion/stiffness of knee and ankle (35%), and pain on the transport site (21%).&#x0D; Conclusion. Ipsilateral medial fibular transport using the Ilizarov frame provides a viable alternative treatment option for the treatment of massive tibial bone defects.

Clinical Faceoff: The Complex Tibial Plafond Fracture: ORIF or Circular External Fixation?

Clinical Faceoff: The Complex Tibial Plafond Fracture: ORIF or Circular External Fixation?

Midterm Outcomes of Tantalum Metal Cones for Severe Bone Loss in Complex Primary and Revision Total Knee Arthroplasty.

BackgroundManaging severe periarticular bone loss poses a major challenge in complex primary and revision total knee arthroplasty (TKA). Impaction bone graft, structural allografts, metal augments, and mega prosthesis are some of the methods used to address major bone loss. Tantalum metal (TM) Cones (Zimmer, Warsaw, IN) were introduced as an alternative to address this cohort of patients. The advantages of these cones include excellent biocompatibility, high porosity with osteoconductive potential, and a modulus of elasticity between cortical and cancellous bone. In addition, it is bioactive and offers an intrinsically high friction fit.MethodsA cohort of 62 patients with severe distal femoral and proximal tibial bone loss were operated for primary and revision TKA between January 2007 and December 2014 and followed up for a mean period of 108.5 months (range: 60-156 months). Preoperative and postoperative range of motion and Knee Society score were documented. Postoperatively long leg X-rays were performed at each follow-up visit to determine osteointegration, evidence of loosening, and migration.ResultsThe range of motion and Knee Society score improved considerably from preoperative a value of 63.9 ± 13.9° and 52 ± 14.9 to 102.1 ± 9.9° and 76.1 ± 10.03, respectively, at the final follow-up visit in the primary cohort and 52.14 ± 13.3° and 38.1 ± 9.1 to 92 ± 8° and 68.5 ± 4.3, respectively, in the revision cohort. Serial radiographs demonstrated complete osteointegration of the TM cones at the final follow-up.ConclusionsOur study demonstrates excellent midterm survivorship of TM cones with predictable osteointegration and good outcomes (clinical and radiological) in treatment of severe femoral and tibial metaphyseal bone defects in complex primary and revision TKAs.

Cambridge Protocol for Management of Segmental Bone Loss

Introduction:Segmental long bone defects are some of the most challenging to surgically reconstruct; however, there is no clear guidance on which of the myriad of techniques is superior in a given clinical context. We describe three cases of segmental bone loss presenting to a major trauma center and have use these to develop a treatment algorithm for the sub-acute management of such fractures.Case Report:Case 1 - Acute shortening and delayed lengthening using lengthening intramedullary (IM) nail to treat diaphyseal non-union of the femur with associated 3 cm shortening. Case 2 - 15 cm traumatic bone loss of femur, failed Masquelet, treated with IM nail, monolateral external-fixation and cable with a mean lengthening rate of 46 days/cm. Case 3 – 12 cm tibial traumatic bone loss, failed Masquelet, treated with fine wire frame with a mean lengthening rate of 49 days/cm.Conclusion:As our cases illustrate; attempting complicated, definitive management in the acute phase generates complications and necessitates re-intervention. As such, we have developed a treatment algorithm for traumatic segmental bone loss. We recommend waiting 6 weeks and reimaging to check for evidence of spontaneous bone formation before deciding on definitive treatment. First-line treatment for femoral defects <4 cm is acute limb shortening with delayed lengthening using lengthening IM nail. First-line treatment for femoral defects >4 cm is lengthening over nail with monolateral external fixator. First-line treatment of tibial segmental bone defects in our hands is fine wire circular frames which provide excellent scope for soft tissue coverage and deformity correction. Treatment times of over 2 years in a frame are not uncommon and patients must diligently comply with pin sites management and lengthening protocols. This is the first paper providing an algorithm to guide surgeons in choosing the best lower limb reconstruction options in the sub-acute setting; considering the skill set and resources of the center in which one works.

Tibial bone loss in revision TKA: Options for management without sleeves and cones –a schematic review

The current study is to distinguish between osteochondrosis and osteochondritis, utilizing surface microscopy of individuals with documented pathology. Osteochondrosis is associated with smooth borders and gradient from edge to defect base, while osteochondritis and subchondral impaction fractures are associated with subsidence of the affected area of articular surface with irregular edges. The base of osteochondrosis is penetrated by multiple channels, smoothly perforate its surface, indistinguishable from unfused epiphyses, confirming their vascular nature. This study provides a technique for distinguishing osteochondrosis and osteochondritis and further documents of the value of epi-illumination microscopy in expanding our understanding of bone and joint disease.

Ilizarov bone transport using an intramedullary cable transportation system in the treatment of tibial bone defects.

Segmental tibia defects remain challenging for orthopedic surgeons to treat. The aim of this study was to demonstrate bone-related and functional outcomes after treatment of complex tibial bone defects using Ilizarov bone transport with a modified intramedullary cable transportation system (CTS). We conducted a single-center, retrospective study including all 42 patients treated for tibial bone loss via Ilizarov bone transport with CTS between 2005 and 2018. Bone-related and functional results were evaluated according to the Association for the Study and Application of Methods of Ilizarov (ASAMI) scoring system. Complication and failure rates were determined by the patients' medical files. Patients had a mean age of 45.5 ± 15.1 years. The mean bone defect size was 7.7 ± 3.4 cm, the average nonunion scoring system (NUSS) score was 59 ± 9.5 points, and the mean follow-up was 40.8 ± 24.4 months (range, 13-139 months). Complete bone and soft tissue healing occurred in 32/42 patients (76.2%). These patients had excellent (10), good (17), fair (2), and poor (3) results based on the ASAMI functional score. Regarding bone stock, 19 patients had excellent, 10 good, and 3 fair results. In total, 37 minor complications and 62 major complications occurred during the study. In 7 patients, bone and soft tissue healing occurred after CTS failure with either an induced membrane technique or classic bone transport; 3 patients underwent lower leg amputation. Patients with treatment failure were significantly older (57.6 vs. 41.8 years; p=0.003). Charlson score and treatment failure had a positive correlation (Spearman's rho 0.43; p=0.004). Bone transport using both intramedullary CTS and Ilizarov ring fixation is viable for treating patients with bone loss of the tibia and complex infection or soft tissue conditions. However, a high number of complications and surgical revisions are associated with the treatment of this severe clinical entity and should be taken into account.