Cite this article: Bone Jt Open 2024;5(12):1120–1122.

Aims. Distal femoral osteotomies (DFOs) are commonly used for the correction of valgus deformities and lateral compartment osteoarthritis. However, the impact of a DFO on subsequent total knee arthroplasty (TKA) function remains a subject of debate. Therefore, the purpose of this study was to determine the effect of a unilateral DFO on subsequent TKA function in patients with bilateral TKAs, using the contralateral knee as a self-matched control group. Methods. The inclusion criteria consisted of patients who underwent simultaneous or staged bilateral TKA after prior unilateral DFO between 1972 and 2023. The type of osteotomy performed, osteotomy hardware fixation, implanted TKA components, and revision rates were recorded. Postoperative outcomes including the Forgotten Joint Score-12 (FJS-12), Tegner Activity Scale score, and subjective knee preference were also obtained at final follow-up. Results. A total of 21 patients underwent bilateral TKA following unilateral DFO and were followed for a mean of 31.5 years (SD 11.1; 20.2 to 74.2) after DFO. The mean time from DFO to TKA conversion was 13.1 years (SD 9.7) with 13 (61.9%) of DFO knees converting to TKA more than ten years after DFO. There was no difference in arthroplasty implant systems employed in both the DFO-TKA and TKA-only knees (p > 0.999). At final follow-up, the mean FJS-12 of the DFO-TKA knee was 62.7 (SD 36.6), while for the TKA-only knee it was 65.6 (SD 34.7) (p = 0.328). In all, 80% of patients had no subjective knee preference or preferred their DFO-TKA knee. Three DFO-TKA knees and two TKA-only knees underwent subsequent revision following index arthroplasty at a mean of 12.8 years (SD 6.9) and 8.5 years (SD 3.8), respectively (p > 0.999). Conclusion. In this self-matched study, DFOs did not affect subsequent TKA function as clinical outcomes, subjective knee preference, and revision rates were similar in both the DFO-TKA and TKA-only knees at mean 32-year follow-up. Cite this article: Bone Jt Open 2024;5(11):1013–1019

The trapeziometacarpal joint (TMCJ) is the most common hand joint affected by osteoarthritis (OA), and trapezium implant arthroplasty is a potential treatment for recalcitrant OA. This meta-analysis aimed to investigate the efficacy and safety of various trapezium implants as an interventional option for TMCJ OA. Web of Science, PubMed, Scopus, Google Scholar, and Cochrane library databases were searched for relevant studies up to May 2022. Preferred Reported Items for Systematic Review and Meta-Analysis guidelines were adhered to and registered on PROSPERO. The methodological quality was assessed by National Heart, Lung, and Blood Institute tools for observational studies and the Cochrane risk of bias tool. Subgroup analyses were performed on different replacement implants, the analysis was done via Open Meta-Analyst software and P values < 0.05 were considered statistically significant. A total of 123 studies comprising 5752 patients were included. Total joint replacement (TJR) implants demonstrate greater significant improvements in visual analogue scale pain scores postoperatively. Interposition with partial trapezial resection implants was associated with the highest grip strength and highest reduction in the Disabilities of the Arm, Shoulder, and Hand score. Revision rates were highest in TJR (12.3%), and lowest in interposition with partial trapezial resection (6.2%). Total joint replacement and interposition with partial trapezial resection implants improve pain, grip strength, and DASH scores more than other implant options. Future studies should focus on high-quality randomized clinical trials comparing different implants to accumulate higher quality evidence and more reliable conclusions

Cannulated hip screws are frequently used in the management of hip fractures. There have been concerns over the failure rate of the technique and the outcomes of those that subsequently require conversion to total hip replacement (THR). This study utilised a database of over 600 cannulated hip screw (CHS) fixations performed over a 14-year period and followed up for a minimum of one year (1-14). We identified 57 cases where a conversion to THR took place (40 females, 17 males, mean age: 71.2 years). Patient demographics, original mechanism of injury, fracture classification, reason for fixation failure, time until arthroplasty, implant type and post-arthroplasty complications were recorded. Clinical outcomes were measured using the Oxford Hip Score. The failure rate of cannulated screw treatment was 9.4% and the mean time from initial fixation to arthroplasty was 15.4 (16.5) months. Thirty six fractures were initially undisplaced and 21 were displaced. As one might expect the displaced cases tended to be younger but this didn't reach statistical significance [66.5(14.3) vs 72.7(13.1), p=0.1]. The commonest causes of failure were non-union (25 cases, 44%) and avascular necrosis (17 cases, 30%). Complications after THR consisted of one leg length discrepancy and one peri-prosthetic fracture. The mean Oxford score pre-arthroplasty was 12.2 (8.4), improving to 38.4 (11.1) at one-year. Although the pre op Oxford scores tended to be lower in patients with undisplaced fractures and higher ASA scores, the improvement was the same whatever the pre-op situation. The one-year Oxford score and the improvement in score are comparable to those seen in the literature for THR in general. In conclusion, CHS has a high success rate and where salvage arthroplasty is required it can provide good clinical outcomes with low complication rates

Aim. Debridement, antibiotics and implant retention (DAIR) are considered as an optimal curative treatment option for prosthetic joint infection (PJI) when the biofilm is still immature and radical debridement is achievable. There are two main groups of patients suitable for DAIR. Those with an early acute PJI and patients with acute hematogenous PJI. However, there is also a third group of early PJI resulting from a wound healing problem or leaking hematoma. These may be either high or low grade depending on the microorganisms that infected the artificial joint “per continuitatem”. Methods. We retrospectively analysed 100 successive DAIR procedures on prosthetic hip and knee joints performed between January 2010 and January 2022, from total of 21000 primary arthroplasties implanted within the same time period. We only included PJI in primary total replacements with no previous surgeries on the affected joint. Patients data (demographics, biochemical, microbiological, histopathological results, and outcomes) were collected from hospital bone and joint infection registry. The aim of surgery was radical debridement and the mobile parts exchange. The standardized antibiotic regime based on antibiofilm antibiotics. Results. The mean age of patients was 70 years (60% women, 43 hips, 57 knees) with a mean follow-up of 3 years. 45 cases were early acute or related to wound healing problems, 55 were hematogenous PJI. 25 patients received preoperative antibiotics. 6 of these were culture negative. The mean symptom duration was 7 days. Mean age of the prosthesis was 30 days for early, and 1064 days for the hematogenous group. Conclusions. In our cohort the success rate of DAIR is 94% which indicates that the protocol is highly successful in PJI with short-lasting symptoms and “debridable” joints. Antibiotic protocol violation and duration of symptoms may have a role in failures

Problem. The identification of unknown orthopaedic implants is a crucial step in the pre-operative planning for revision joint arthroplasty. Compatibility of implant components and instrumentation for implant removal is specific based on the manufacturer and model of the implant. The inability to identify an implant correctly can lead to increased case complexity, procedure time, procedure cost and bone loss for the patient. The number of revision joint arthroplasty cases worldwide and the number implants available on the market are growing rapidly, leading to greater difficulty in identifying unknown implants. Solution. The solution is a machine-learning based mobile platform which allows for instant identification of the manufacturer and model of any implant based only on the x-ray image. As more surgeons and implant representatives use the platform, the model should continue to improve in accuracy and number of implants recognized until the algorithm reaches its theoretical maximum of 99% accuracy. Market. Multiple organizations have created small libraries of implant images to assist surgeons with manual identification of unknown implants based on the x-ray, however no automated implant identification system exists to date. One of the most financially successful implant identification tools on the market is a textbook of hip implants which sells for a per unit cost of $200. Several free web-based resources also act as libraries for the manual identification of a limited number of arthroplasty implants. A number of academic and private organizations are working on the development of an automated system for implant identification, however none are available to the public. Product. Implant Identifier is mobile application which uses machine-learning to instantly detect the model and manufacturer of any common arthroplasty implant, based only on x-ray. The beta version offers a large library of implants for manual identification and is currently available for free download on iOS and Android. Its purpose is to further develop the model to its maximal theoretical accuracy, prior to official release. The beta version of the application currently has over 15,000 registered users worldwide and has the largest publicly available arthroplasty library available on the market. Over 200,000 implant images have been submitted by users to date. Timescales. The product was initially released in the form of a closed beta which became available to invited guests around 18 months ago. The current version is an open beta which can be downloaded and used by any individual. It was released roughly 12 months ago. The final rendition of the application will allow for free manual identification using the implant library, as well as subscription-based automated implant identification. The implementation, testing and release of this final subscription product is projected to be completed by Q3 2022. Funding. A small number of early investors have funded the initial research and development of the beta product; however, another round of investment will be beneficial in the final evolution of the product. This additional investment round will allow for completion of development of the identification algorithm, product dissemination, customer support, and lasting sustainability of the venture

Introduction & Aims. In other medical fields, smart implantable devices are enabling decentralised monitoring of patients and early detection of disease. Despite research-focused smart orthopaedic implants dating back to the 1980s, such implants have not been adopted into regular clinical practice. The hardware footprint and commercial cost of components for sensing, powering, processing, and communicating are too large for mass-market use. However, a low-cost, minimal-modification solution that could detect loosening and infection would have considerable benefits for both patients and healthcare providers. This proof-of-concept study aimed to determine if loosening/infection data could be monitored with only two components inside an implant: a single-element sensor and simple communication element. Methods. The sensor and coil were embedded onto a representative cemented total knee replacement. The implant was then cemented onto synthetic bone using polymethylmethacrylate (PMMA). Wireless measurements for loosening and infection were then made across different thicknesses of porcine tissue to characterise the sensor's accuracy for a range of implantation depths. Loosening was simulated by taking measurements before and after compromising the implant-cement interface, with fluid influx simulated with phosphate-buffered saline solution. Elevated temperature was used as a proxy for infection, with the sensor calibrated wirelessly through 5 mm of porcine tissue across a temperature range of 26–40°C. Results. Measurements for loosening and infection could be acquired simultaneously with a duration of 4 s per measurement. For loosening, the debonded implant-cement interface was detectable up to 10 mm with 95% confidence. For temperature, the sensor was calibrated with a root mean square error of 0.19°C at 5 mm implantation depth and prediction intervals of ±0.38°C for new measurements with 95% confidence. Conclusions. This study has demonstrated that with only two onboard electrical components, it is possible to wirelessly measure cement debonding and elevated temperature on a smart implant. With further development, this minimal hardware/cost approach could enable mass-market smart arthroplasty implants

Radiostereometric analysis (RSA) allows for precise measurement of interbody distances on X-ray images, such as movement between a joint replacement implant and the bone. The low radiation biplanar EOS imager (EOS imaging, France) scans patients in a weight-bearing position, provides calibrated three-dimensional information on bony anatomy, and could limit the radiation during serial RSA studies. Following the ISO-16087 standard, 15 double exams were conducted to determine the RSA precision of total knee arthroplasty (TKA) patients in the EOS imager, compared to the standard instantaneous, cone-beam, uniplanar digital X-ray set-up. At a mean of 5 years post-surgery, 15 TKA participants (mean 67 years, 12 female, 3 male) were imaged twice in the biplanar imager. To reduce motion during the scan, a support for the foot was added and the scan speed was increased. The voltage was also increased compared to standard settings for better marker visibility over the implant. A small calibration object was included to remove any remaining sway in post-processing. The 95% confidence interval precision was 0.11, 0.04, and 0.15 mm in the x, y, and z planes, respectively and 0.15, 0.20, and 0.14° in Rx, Ry, and Rz. Two participants had motion artifacts successfully removed during post-processing using the small calibration object. With faster speeds and stabilization support, this study found an in vivo RSA precision of ≤ 0.15 mm and ≤ 0.20° for TKA exams, which is within published uniplanar values for arthroplasty RSA. The biplanar imager also adds the benefits of weight bearing imaging, 3D alignment measurements, a lower radiation dose, and does not require a reference object due to known system geometry and automatic image registration

Aims

To explore the clinical efficacy of using two different types of articulating spacers in two-stage revision for chronic knee periprosthetic joint infection (kPJI).

Introduction. Automated identification of arthroplasty implants could aid in pre-operative planning and is a task which could be facilitated through artificial intelligence (AI) and deep learning. The purpose of this study was to develop and test the performance of a deep learning system (DLS) for automated identification and classification of knee arthroplasty (KA) on radiographs. Methods. We collected 237 AP knee radiographs with equal proportions of native knees, total KA (TKA), and unicompartmental KA (UKA), as well as 274 radiographs with equal proportions of Smith & Nephew Journey and Zimmer NexGen TKAs. Data augmentation was used to increase the number of images available for DLS development. These images were used to train, validate, and test deep convolutional neural networks (DCNN) to 1) detect the presence of TKA; 2) differentiate between TKA and UKA; and 3) differentiate between the 2 TKA models. Receiver operating characteristic (ROC) curves were generated with area under the curve (AUC) calculated to assess test performance. Results. The DCNNs trained to detect KA and to distinguish between TKA and UKA both achieved AUC of 1. In both cases, heatmap analysis demonstrated appropriate emphasis of the KA components in decision-making. The DCNN trained to distinguish between the 2 TKA models also achieved AUC of 1. Heatmap analysis of this DCNN showed emphasis of specific unique features of the TKA model designs for decision making, such as the anterior flange shape of the Zimmer NexGen TKA (Figure 1) and the tibial baseplate/stem shape of the Smith & Nephew Journey TKA (Figure 2). Conclusion. DCNNs can accurately identify presence of TKA and distinguish between specific designs. The proof-of-concept of these DCNNs may set the foundation for DCNNs to identify other prosthesis models and prosthesis-related complications. For any figures or tables, please contact the authors directly

The use of artificial intelligence (AI) is rapidly growing across many domains, of which the medical field is no exception. AI is an umbrella term defining the practical application of algorithms to generate useful output, without the need of human cognition. Owing to the expanding volume of patient information collected, known as ‘big data’, AI is showing promise as a useful tool in healthcare research and across all aspects of patient care pathways. Practical applications in orthopaedic surgery include: diagnostics, such as fracture recognition and tumour detection; predictive models of clinical and patient-reported outcome measures, such as calculating mortality rates and length of hospital stay; and real-time rehabilitation monitoring and surgical training. However, clinicians should remain cognizant of AI’s limitations, as the development of robust reporting and validation frameworks is of paramount importance to prevent avoidable errors and biases. The aim of this review article is to provide a comprehensive understanding of AI and its subfields, as well as to delineate its existing clinical applications in trauma and orthopaedic surgery. Furthermore, this narrative review expands upon the limitations of AI and future direction.

Cite this article: Bone Joint Res 2023;12(7):447–454.

Aims

This study aimed to analyze kinematics and kinetics of the tibiofemoral joint in healthy subjects with valgus, neutral, and varus limb alignment throughout multiple gait activities using dynamic videofluoroscopy.

Aims

Periprosthetic fractures (PPFs) following hip arthroplasty are complex injuries. This study evaluates patient demographic characteristics, management, outcomes, and risk factors associated with PPF subtypes over a decade.

Aims

The proximal tibia (PT) is the anatomical site most frequently affected by primary bone tumours after the distal femur. Reconstruction of the PT remains challenging because of the poor soft-tissue cover and the need to reconstruct the extensor mechanism. Reconstructive techniques include implantation of massive endoprosthesis (megaprosthesis), osteoarticular allografts (OAs), or allograft-prosthesis composites (APCs).

Aims

The aim of the HIPGEN consortium is to develop the first cell therapy product for hip fracture patients using PLacental-eXpanded (PLX-PAD) stromal cells.

The age spectrum for patients undergoing shoulder arthroplasty is broadening. Many younger patients now demonstrate shoulder pathology precluding non-arthroplasty reconstruction. The senior population is living longer and “younger”. Therefore, the demands of this patient population to participate in an active lifestyle are growing. Patients with osteoarthritis, cuff tear arthropathy, post-traumatic arthropathy, avascular necrosis, and even forms of inflammatory arthropathy present seeking not only return to simple activities of daily living but the ability to participate in aerobic recreational activities and even work activities which can stretch the limits of shoulder arthroplasty in the physiologic environment of the shoulder. This presentation will provide an overview of patient demands, concerns and activity level following shoulder arthroplasty. We will provide a prospective of allowable, recommended and discouraged activities depending on the underlying source of pathology in the type of arthroplasty implants employed. An overview of our four phases of rehabilitation protocol will be presented focusing on phase four, “work in sports hardening”

The Failed Femoral Neck Fracture. For the young patient: Attempt to preserve patient's own femoral head. Clinical results reasonably good even if there are patches of avascular necrosis. Preferred methods of salvage: valgus-producing intertrochanteric femoral osteotomy: puts the nonunion under compression. Other treatment option: Meyer's vascularised pedicle graft. For the older patient: Most reliable treatment is prosthetic replacement. Decision to use hemiarthroplasty (such as bipolar) or THA based on quality of articular cartilage, perceived risk of instability problem. In most patients THA provides higher likelihood of excellent pain relief. Specific technical issues: (1) hardware removal: usually remove after hip has first been dislocated (to reduce risk of femur fracture); (2) Hip stability: consider methods to reduce dislocation risk: larger diameter heads/dual mobility/anteriorly-based approaches; (3) Acetabular bone quality: poor because it is not sclerotic from previous arthritis; caution when impacting a pressfit cup; low threshold to augment fixation with screws; don't overdo reaming; just expose the bleeding subchondral bone. A reasonable alternative is a cemented cup. The Failed Intertrochanteric Hip Fracture. For the young patient: Attempt to salvage hip joint with nonunion takedown, autogenous bone grafting and internal fixation. For the older patient: Decision to preserve patient's own hip with internal fixation versus salvage with hip arthroplasty should be individualised based on patient circumstances, fracture pattern, bone quality. THA is an effective salvage procedure for this problem in older patients. If prosthetic replacement is chosen special considerations include:. THA vs. hemiarthroplasty: hemiarthroplasty better stability; THA more reliable pain relief. Removal of hardware: be prepared to remove broken screws in intramedullary canal. Management of bone loss: bone loss to level of lesser trochanter common. Often requires a calcar replacement implant. Proximal calcar build-up size dictated by bone loss. Length of stem: desirable to bypass screw holes from previous fixation, if possible. Stem fixation: cemented or uncemented fixation depending on surgeon preference, bone quality. If uncemented, consider diaphyseal fixation. Greater trochanter: often a separate piece, be prepared to fix with wires or cable grip. Residual trochanteric healing, hardware problems not rare after THA

Aims

Unicompartmental and total knee arthroplasty (UKA and TKA) are successful treatments for osteoarthritis, but the solid metal implants disrupt the natural distribution of stress and strain which can lead to bone loss over time. This generates problems if the implant needs to be revised. This study investigates whether titanium lattice UKA and TKA implants can maintain natural load transfer in the proximal tibia.

Demographic changes will increase the number of surgical procedures in the next years. Therefore, quality assurance of clinical processes, such as the reprocessing of surgical instruments as well as intraoperative workflows will be of increasing importance to ensure patient safety. Surgical procedures are often complex and may involve risks for the patient. For fixation of screws, e.g. in case of pedicle screws, osteosynthesis plates or revision joint replacement surgery implants, the application of defined torques may be crucial in order to achieve optimal therapeutic results and minimal complication rates. In many cases a subjective rating of the surgeon is necessary as no adequate instrumentation is available. With the same subjective feeling, hammering or screwing in are performed to implant e.g. the acetabular component in THA. Our actual work is dedicated to the implementation of a functional prototypes of sensor- integrated instruments for specific types of intervention (especially in traumatology) and the evaluation of the sensor integrated surgical instruments in combination with RFID technology for smart process optimisation in the operating room as well as for reprocessing of surgical instruments and surgical management in combination with a knowledge-based planning, control and documentation system. Complementary (preferably wireless) sensors such for instrument identification, tracking or more complex measurements such as forces, torques, temperature or impacts during surgery as well as during reprocessing of reusable instruments could enable computer network based quality assurance in a much broader and comprehensive manner. Within the framework of the OR.NET initiative we follow the approach to integrate wireless sensors for measurement of temperature, force-torque as well as inertial sensors for orientation and impact control, depending on the specific type of application for monitoring of workflows during surgery as well as during reprocessing of reusable instruments and devices. The integration of smart surgical instruments into an open networked operating room based on the open communication standard IEEE 11073 knowledge-based workflow system, can help to improve the process and quality management

Arthroplasty implant modularity enables the surgeon to adapt the joint replacement construct to the patient's requirements, and often facilitates revision procedures. Total shoulder arthroplasty humeral modularity exists for many implant systems. Glenoid modularity with convertibility between anatomic and reverse shoulder arthroplasty is a recent development. Glenoid modularity is very useful when reconstructing glenoid bone deficiencies, or in providing a method for reverse shoulder arthroplasty joint lateralization. The live surgery will demonstrate a bio-reverse total shoulder arthroplasty (bRTSA). The humeral component is a modular press fit stem that can accommodate either reverse or anatomic metaphyseal components. The metaphyseal components can be exchanged without removing the stem or changing the humeral height. The glenoid base has three components. The trabecular titanium peg is available in two diameters, and four lengths for each diameter. The peg is fixed to a metal base plate via Morse taper. In revision settings, these components can be easily dissociated in situ, and a coring drill inserted over a well-fixed peg allows removal with minimal bone loss. Either a polyethylene component, or glenosphere can be attached to the baseplate to complete the glenoid construct. An innovative set of instruments have been developed to reliably prepare the glenoid and humeral bone graft. While the live surgery will demonstrate the grafting technique in a bRTSA, it can also be used to reconstruct glenoid deficiencies (eg, Walch B2). Implants have been developed to solve these issues, but often do so at the expense of very limited glenoid bone stock. Bone grafting actually creates a net increase in glenoid bone stock that may improve implant durability, and decrease revision complexity. The technique is quite simple and adds approximately ten minutes to operative time. I have used this technique for 5 years with no cases of graft failure