Bone Cuts Research Articles

Cartilage thickness can be accurately measured intraoperatively in total knee arthroplasty: A step further in calipered kinematic alignment.

Kinematic alignment (KA) in total knee arthroplasty (TKA) is by definition a pure femoral resurfacing procedure aiming to restore the individual prearthritic anatomy. However, when a 2 mm compensation is systematically used on the worn side, the variability in cartilage thickness in the unworn compartment might alter the accuracy of the technique. This study aimed to validate two intraoperative femoral cartilage thickness measurement techniques by comparing them to the photographic method, which measures cartilage thickness through pixel analysis of bone-cut images. The study hypothesized that the two intraoperative methods are comparable and similarly accurate within 0.5 mm of the photographic method. Seventy cartilage thickness measurements from seventy patients with end-stage knee osteoarthritis were prospectively collected. Two intraoperative techniques were evaluated: the electrocautery tip method (Method A) and the ruler method (Method B), performed before and after distal femoral bone resections, respectively. The postoperative photographic analysis (Method C) served as the reference method. Measurements were rounded to the nearest 0.5 mm for consistency. Data were analyzed using Kruskal-Wallis test, Wilcoxon rank-sum tests, Spearman's rank correlation, percentage of agreement and intraclass correlation coefficients (ICCs). No significant differences were observed between Method A and Method B in measuring femoral cartilage thickness. Agreement with Method C was 100% for Method B and 85% for Method A. In the 15% of discordant cases, Method A overestimated the measurements by one category of 0.5 mm compared to Method C. Correlation coefficients between the methods were high (ρ = 0.88-1.0). Intra- and interobserver reliability was high for all methods (ICCs 0.91-0.95). Both intraoperative methods are reliable and comparable to the photographic method when rounded to the closest 0.5 mm, with no significant differences among them. The electrocautery method has the added advantage of measuring cartilage thickness before bone cuts are performed. Level IV.

Navigated instrumentation and ligament tensioning device enhances initial gap acquisition during total knee arthroplasty procedure: A cadaveric study.

Gap-balanced total knee arthroplasty (TKA) technique relies on initial ligament evaluation, particularly in patient-specific implantation using computer-assisted technologies. This cadaveric study aimed to compare the reproducibility and reliability of medial and lateral gap measurements between manual stress testing and dynamic ligament balancer. Initial gap acquisitions were assessed from eight cadaveric knees (four specimens) during the same navigated TKA procedure by five differently skilled surgeons (three seniors and two juniors). Medial and lateral gaps were sequentially acquired from extension to maximum knee flexion, applying manual stress prior to any bone cuts (conventional technique), and using intra-articular tensioning device placed between the tibial cut and the native femur (instrumented technique). Reproducibility was assessed using intraclass correlation coefficient (ICC), stratified by the measurement technique, the type of gaps and the operator experience. Differences in gaps (mm) between techniques were assessed using the Bland and Altmann method. The instrumented technique showed higher ICCs than the conventional technique for medial and lateral gaps (0.87 vs. 0.60, P = 0.002, and 0.92 vs. 0.25, p < 0.0001, respectively), and showed no difference in ICCs between medial and lateral gap acquisitions (0.87 vs. 0.92, p = 0.8). Senior surgeons achieved higher ICCs than juniors, while non-significant with both techniques. Differences in gaps between techniques increased with knee flexion angle (0.8, 2.8 and 3.5 mm at 10°, 45° and 90° of flexion angle, respectively) and decreased with the operator experience (p = 0.003). The instrumented balancing technique offered better reproducibility than using manual valgus and varus stress, when measuring medial and lateral gaps. Tensioning devices may play a significant role in enhancing initial gap acquisition, disregarding the flexion angle and the operator experience. Level IV (observational study involving cadaveric specimens).

Guide-wire and K-wire readjustment jig for osteotomy and osteosynthesis: An instrument.

Numerous orthopaedic procedures including dynamic hip screw plating and various osteotomies require placement of a reference guide pin or K wire to direct bone cuts or for drilling screw holes. Appropriate positioning of these wires is a critical component of surgery. Irrespective of whether one is a seasoned surgeon or an apprentice, these wires often need repositioning and readjustment. Parallel wire positioning is needed even during procedures like osteotomies or patellar fracture fixation. Though there are several tools available to help with accurate placement of wires and saving operating time, there are very few tools which can actually control the direction or angulation of the wire. The ones which are available are usually difficult to use, are bulky, have long attachments arms or have too many fine adjustments. We propose a device that not only directs the positioning of the parallel wires but also helps with a 360-degree correction in direction of the wrongly positioned wire. It is a multipurpose jig that can be used in patella fracture, inter-trochanteric fracture femur, fracture neck of femur, osteotomies around knee, elbow and distal femur, etc. We proposed, designed and manufactured a new device for the guide wire insertion. Our jig design has three tunnels. Two tunnels, primary and secondary run parallel to each other and the oblique tunnel runs at an angle and is positioned 7mm away from the parallel tunnel at one end and shares a common opening with the secondary tunnel on opposite end. Other similar jigs either have only parallel tunnels (primary and secondary) or an oblique tunnel which is at the far end of metal bar, making it difficult to be used to correct the angular direction of the guidewire in reference to primary or secondary wire. Using our newer device, wires can be guided in all directions and in all planes (sagittal, coronal, axial, and 360°). Correction of the wire direction using this jig is significantly easier and faster, a process which can take anywhere between 15min and an hour of surgical time for a beginner orthopaedic surgeon. The need for multiple repeated attempts to insert wires, resulting in a bone void and damage to the surrounding structures, is minimised or eliminated. Applications include a variety of surgical procedures of osteosynthesis and osteotomies. In conclusion, our device is easier to use as it is smaller in size and available in different sizes and angles. It not only avoids bone loss and fragmentation due to repetitive insertion of wires but also improves the accuracy of primary reference wire placement or revision of its direction.

Robotic Assistance Is Not Associated With Decreased Early Revisions in Cementless TKA: An Analysis of the American Joint Replacement Registry.

Previously, we conducted a retrospective study of American Joint Replacement Registry (AJRR) data that examined the 2-year odds of revision between robotic-assisted and nonrobotic-assisted TKA, and we found no benefit to robotic assistance. However, proponents of robotic assistance have suggested that robot platforms confer more accurate bone cuts and precise implant sizing that might promote osteointegration of cementless implants by limiting micromotion at the bone-implant interface that could lead to aseptic loosening. Therefore, it seems important specifically to evaluate the odds of revision among patients with cementless implants only within our previous study population. (1) After controlling for potentially confounding variables, such as surgeon, institution, and patient comorbidity profile, was robotic assistance associated with a decreased odds of 2-year revision of cementless TKA for any reason compared with cementless TKAs performed without robotic assistance? (2) After again controlling for potentially confounding variables, was robotic assistance associated with a decreased odds of 2-year revision of cementless TKA for particular revision indications (such as aseptic loosening, infection, instability, or pain) compared with the cementless TKAs performed without robotic assistance? Using the AJRR, a retrospective cohort of patients ≥ 65 years of age with osteoarthritis who underwent primary TKA with cementless femur and tibial components from January 2017 through March 2020 was identified. Procedures performed with hybrid fixation (cement only on the tibia but not on the femur, or vice versa) were excluded. The AJRR was selected because it is the largest arthroplasty registry in the world by annual procedure volume, and it contains a data linkage with inpatient and outpatient Medicare claims data to ensure near-complete 2-year follow-up. A total of 9220 patients were identified, and robotic assistance was used in 45% (4130) of procedures. Patient age did not differ between groups (72 ± 5 years versus 72 ± 5 years; p = 0.29). However, the robotic-assisted cohort had a slightly higher proportion of female patients (56% [2332 of 4130] versus 53% [2693 of 5090]; p = 0.002) and higher Charlson comorbidity index (CCI) (2.9 ± 0.9 versus 2.8 ± 0.9; p = 0.003). Therefore, a mixed-effects model was used to analyze the ORs for all-cause linked revision with robotic assistance and was adjusted for age, gender, CCI, surgeon, and institution. Subanalyses were performed on indications for revision. A power analysis demonstrated the ability to measure a difference as small as one-half SD between risk of revision within each cohort (specifically, moderate effect sizes based on Cohen d). After controlling for potentially confounding variables, such as surgeon, location of surgery, and patient comorbidity profile, we found no difference regarding odds of all-cause revision between robotic-assisted and nonrobotic-assisted cementless TKA (OR of robotic-assisted versus nonrobotic-assisted cementless TKA 0.8 [95% CI 0.5 to 1.3]; p = 0.41). There were no differences in reasons for revision between robotic-assisted and nonrobotic-assisted cementless TKA, such as mechanical loosening (OR 3.2 [95% CI 0.8 to 12]; p = 0.09) and infection (OR 1.5 [95% CI 0.8 to 2.6]; p = 0.19). We found no evidence that robotic assistance improves the odds of cementless implant survival free from revision at 2 years. Importantly, the differences in odds of revision beyond 2 years as a function of robotic assistance in cementless TKA remains unknown and warrants further population-level investigation, but until or unless robotic assistance proves its value in well-designed studies in terms of endpoints that patients can perceive (such as pain, function, or survivorship), we recommend against widespread adoption until further evidence becomes available. Additionally, we encourage surgeons and healthcare facilities using robotic assistance in cementless TKAs to study its impact on patient outcomes, if any. Level III, therapeutic study.

High accuracy of component positioning and restoration of lower limb alignment using robotic medial unicompartmental knee arthroplasty.

Unicondylar arthroplasty was performed using robotic medial unicompartmental knee arthroplasty (R-mUKA) and gap-balancing instrumentation. Our hypothesis was that robotic unicondylar knee arthroplasty accurately restores component positioning and lower limb alignment when compared to preoperative planning with actual implantation throughout the range of knee motion due to proper knee balancing. Data were collected prospectively and were analysed for patients undergoing RM-UKA. A cemented UKA was implanted using the MAKO® robotic system. Lower limb alignment at 0°, 30°, 45°, 60° and 90° of flexion was recorded of the native knee, with the trial components in place and finally after component implantation. A spacer according to the femorotibial gap was introduced and the alignment was measured. The position of the final component was planned based on three-dimensional computed tomography images before making the bone cuts. The positioning of the femoral and tibial components was analysed in all three planes. A total of 52 patients were included (mean age 66.3 ± 6.7 years; 34 males, 18 females). The difference in femoral component position after planning and final implantation was 0.04° ± 0.58° more valgus in the coronal plane (p = 0.326) and 0.6° ± 1.4° more flexion relative to the sagittal plane (p = 0.034). The tibial component was placed in the coronal plane in 0.3° ± 0.8° of more varus (p = 0.113) and in the sagittal plane in 0.6° ± 1.2° of more posterior tibial slope (p = 0.001). Lower limb alignment of the native knee in extension was 5.8° ± 2.6° of varus and changed to 3° ± 2.1° varus after UKA (p ≤ 0.01). R-mUKA helps to achieve the target of alignment and component position without any significant differences to the planning. Ligament balancing causes non-significant changes in component position. It allows optimal component position even for off-the-shelf implants respecting the patient's specific anatomy. II.

Assessing the Feasibility of Selective Piezoelectric Osteotomy in Transorbital Approach to the Middle Cranial Fossa: Anatomical and Quantitative Study and Surgical Implications

ObjectivesTo verify the feasibility and to discuss advantages and disadvantages of a piezoelectric orbitotomy (PO) during Superior Eyelid Endoscopic Transorbital Approach (SETOA). MethodsFive adult specimens underwent exoscopic/endoscopic SETOA to middle cranial fossa. The surgical corridor was created via piezoelectric orbitotomy by performing three selective and safe micrometric bone cuts providing a one-piece trapezoid bone flap which was repositioned and secured at the end of procedure. A 3D scan of the bone flap allowed us to reconstruct a 3D model and calculate its volume. An illustrative case demonstrating the application of this novel technique was also presented. ResultsAnatomical-morphometric quantitative analysis showed a mean bony-volume gain of 1,574.26 mm3 by using PO.PO yielded concrete surgical advantages and theoretical benefits in terms of functional and esthetic outcomes. All osteotomies were micrometric clear-cut and precise, resulting in a very thin bony gap; a complete sparing of soft tissues and neurovascular structures in- and around the orbit was observed. Lateral orbital wall reconstruction by replacing the bone flap aims to mitigate the risk of enophthalmos, proptosis, CSF leakage, pseudomeningocele and pulsatile headache, which represent significant challenges in the relevant literature. ConclusionPO may offer a viable, selective, effective, safe alternative to high-speed drilling during SETOA, especially for patients affected by intra-axial pathologies in which a watertight closure is mandatory. This procedure could prevent/decrease the risk of some of the main postoperative complications associated to the standard SETOA, resulting potentially in better functional and esthetic outcome.

Bone Cutter versus Oscillating Saw for Ray Amputation: A Protocol for Randomised Controlled Feasibility Trial comparing Outcomes between Metatarsal Methods of Transection (MetaMet)

Background Ray amputation is commonly performed for irretrievable digital infections and/or ischemia, particularly in diabetic foot disease. Re-ulceration and reoperation rates after toe amputation range from 43-65%. Numerous studies have investigated patient-dependent factors of wound healing, including diabetes, malnutrition, smoking, and renal failure. However, there has been minimal research on the impact of technical surgical factors on patient outcomes. Methods This protocol describes a single-center, prospective, randomized controlled, assessor-blinded feasibility study comparing outcomes after ray amputation between two accepted methods: metatarsal transection, manual bone cutter (BC), or an oscillating microsaw (OS). The inclusion criteria were adults undergoing toe amputation via metatarsal transection capable of providing informed consent. The exclusion criteria were significant peripheral arterial disease (ABPI &lt;0.4) and en bloc resection of three or more toes. Participants will be allocated to one of two parallel groups in a 1:1 fashion using randomization by minimization, stratifying for chronic kidney disease (eGFR &lt;60 mL/min/1.73 m2) and palpable pulses. The primary objective was to gather sufficient data to accurately power a future definitive trial. Secondary outcomes included differences between the two trial arms in re-operation and readmission rates at six months, time to wound healing post-index procedure, and patient-reported postoperative pain scores. Ethical approval was granted for recruitment in January, 2023. Discussion We hypothesized that an OS reproducibly achieves a smoother and more precise cut and produces less bony debris to act as an infective nidus with minimal inter-surgeon variation. Due to a lack of guiding evidence, surgeon preference for ray amputation technique evolves from the ‘apprenticeship’ training model, personal experience, and local equipment availability. We aimed to provide robust data to guide decision-making as the incidence of diabetes increases and the number of minor amputations increases. Trial Registration ClinicalTrials. gov registration NCT05804565 on 26/03/2023

High Tibial Osteotomy in Sport-Related Cases

High Tibial Osteotomy (HTO) is a surgical procedure increasingly employed in sport-related cases with the aim of preserving knee joint function and delaying or altogether avoiding knee compromise. This technique involves the realignment of the tibial plateau through controlled bone cuts, resulting in an optimized distribution of forces on the knee joint. Sport-related activities often lead to unique knee joint stresses, particularly in cases of chronic anterior cruciate ligament (ACL) deficiency, varus malalignment, or early-stage osteoarthritis. HTO offers an alternative treatment option for athletes and active individuals seeking to maintain their performance levels while simultaneously addressing their knee joint issues. This procedure offers an effective approach to alleviate symptoms, correct alignment, improving stability, preserve meniscal tissue and cartilage, The HTO procedure can be a procedure offered along with ligament reconstruction procedures and other soft tissue repairs in the knee in mal-aligned knee conditions. Studies show that there is a relationship between failure of ACL reconstruction and others soft tissue procedurs and mal alignment of the knee Although HTO offers many advantages, careful patient selection and evaluation is essential to maximize the likelihood of a successful outcome. A comprehensive preoperative assessment, including physical examination, radiographic evaluation, and review of detailed medical history, type of exercise, and patient expectations will help identify eligible patients and reduce the potential for complications.

Effect of design and surgical parameters variations in mobile-bearing versus fixed-bearing unicompartmental knee arthroplasty: A finite element analysis.

Unicompartmental knee arthroplasty (UKAs) are available in the market as fixed- and mobile-bearing (FB and MB) and can be characterised by a different set of design parameters in terms of geometries, materials and surgical approaches, with overall good clinical outcomes. However, clear biomechanical evidence concerning the consequences of variations of these features on knee biomechanics is still lacking; therefore, the present study aims to perform a sensitivity analysis to see which outcomes are affected by these variations. For both MB-UKA and FB-UKA, five design and surgical parameters were defined (bearing insert thickness, tibial component material, implant components friction coefficient, antero-posterior slope angle and level of tibial bone resection). Two control models were defined based on standard configurations for both implants. Finite element analysis was chosen to perform this study, and different parameter combinations (216 models in total) were implemented and tested at both 0° and 90° of flexion, using a previously validated finite element knee model. The results were then evaluated in terms of bone and polyethylene Von Mises stress and tibio-femoral contact area. Bearing thickness, tibial bone cut and slope angle were found to be the most sensitive parameters for both types of UKAs. Specifically, changes in these parameters in the FB-UKA appeared to induce more significant variations in the polyethylene insert (both in terms of polyethylene stress and contact area), while in the MB-UKA, these changes influenced bone stress distribution more. Surgical parameters returned to have a more significant influence than material and friction variations; furthermore, the outcomes most affected by parameter variations were the insert-related ones for FB-UKA while for the MB-UKA were the ones regarding tibial bone stresses. Not Applicable.

Efficacy of the Coronoid Notch and Occlusal Plane As Predictable Landmarks for Determining the Medial Cut Height in Bilateral Sagittal Split Osteotomy: A Split-Mouth Observational Study.

This split-mouth observational study was conducted to assess the reliability and safety of using the coronoid notch and occlusal plane as landmarks to aid surgeons during bilateral sagittal split osteotomy(BSSO). Thirteen patients between the ages of 18 and 30 years, with class II and class III mandibular skeletal malocclusion requiring BSSO, were randomly selected and assigned to each of the study and control groups. A split-mouth study was chosen to conduct this research. Cone beam computed tomography (CBCT) imaging was conducted before the surgery to evaluate the anatomical structure, and three predefined points were marked at the superiormost point of the mandibular foramen, the inferiormost point of the mandibular foramen, and the deepest point of the sigmoid notch. A conventional sagittal split osteotomy was carried out in the control group. Preoperative values were obtained in the study group using the CBCT imaging technique by drawing an imaginary line from the inferiormost part of the mandibular foramen to the line corresponding to the occlusal plane that extended beyond the last molar. The lingual flap reflection was restricted to the internal oblique ridge. The posterior border of the mandible was not reflected. The measurements acquired via CBCT imaging were accurately transferred to the intraoperative surgical site using a vernier caliper. This facilitated the precise completion of the horizontal osteotomy, ascending ramus cuts, and vertical osteotomies. BSSO was performed, the mandibular setback or advancement was done with intermaxillary fixation, and the procedure was completed by rigid fixation. Types of lingual splits, types of lateral bone cut ends (LBCEs), any unfavorable split, and the time taken for the surgery (in minutes) were assessed. The surgery time in the control group (20.1538 ± 2.85325 min) was found to be higher than that in the study group (17.6154 ± 3.59487 min), with a p-value of 0.02. No significant differences were observed when assessing the presence of unfavorable splits in both groups (p = 0.500). Buccal LBCEs were the most prevalent, followed by inferior types. Type I lingual split was the most common in the study group (70%). This technique offers a dependable anatomical reference and significantly reduces surgical time for beginners. Additionally, the patterns of the lingual split were correlated with the types of lateral bone cut ends.

Optimizing the patellofemoral compartment in total knee arthroplasty: Is it time for dynamic assessment?

Despite improvements in implant design, surgical techniques and assistive technologies for total knee arthroplasty (TKA), anterior knee pain (AKP) remains frequently reported, even by satisfied patients. This persistent problem calls for better understanding and management of the patellofemoral or anterior compartment during surgery, just as the techniques and strategies deployed to optimize the flexion and extension spaces through personalized alignment, bone cuts and ligament balancing. Assistive technologies such as navigation and robotics provide new tools to manage this 'third space' through precise pre-operative planning and dynamic intra-operative assessment. Such endeavors must start with clear definitions of the 'third space', how it should be measured, what constitutes its 'safe zone', and how it affects outcomes. There are yet no established methods to evaluate the patellofemoral compartment, and no clear thresholds to define over- or under-stuffing. Static assessment using lateral radiographs provides a limited understanding and depends considerably on flexion angle, while dynamic evaluation at multiple flexion angles or using intra-operative computer or robotic-assistance enables a broader perspective and solutions to manage patellar tracking and anterior offset. Future studies should investigate the impact of variations in anterior offset in TKA, define its safe zone, and understand the effects of of thresholds for over- or under-stuffing. Experimental methods such as in-vivo motion analysis and force sensors could elucidate the influence of anterior offset on flexion and extension biomechanics.

A novel robotic surgical assistant for total knee arthroplasty has a learning curve ranging from 6 to 14 cases and exhibits high accuracy in tibial bone cuts

BackgroundThe adoption of robot-assisted total knee arthroplasty (TKA) aims to enhance the precision of implant positioning and limb alignment. Despite its benefits, the adoption of such technology is often accompanied by an initial learning curve, which may result in increased operative times. This study sought to determine the learning curve for the ROSA (Robotic Surgical Assistant) Knee System (Zimmer Biomet) in performing TKA and to evaluate the accuracy of the system in executing bone cuts and angles as planned. The hypothesis of this study was that cumulative experience with this robotic system would lead to reduced operative times. Additionally, the ROSA system demonstrated reliability in terms of the accuracy and reproducibility of bone cuts.MethodsIn this retrospective observational study, we examined 110 medical records from 95 patients who underwent ROSA-assisted TKA performed by three surgeons. We employed the cumulative summation methodology to assess the learning curves related to operative time. Furthermore, we evaluated the accuracy of the ROSA Knee System in performing TKA by comparing planned versus validated values for femoral and tibial bone cuts and angles.ResultsThe learning curve for the ROSA Knee System spanned 14, 14, and 6 cases for the respective surgeons, with operative times decreasing by 22 min upon reaching proficiency (70.8 vs. 48.9 min; p < 0.001). Significant discrepancies were observed between the average planned and validated cuts and angles for femoral bone cuts (0.4 degree ± 2.4 for femoral flexion, 0.1 degree ± 0.6 for femoral coronal alignment, 0.3 mm ± 1.2 for distal medial femoral resection, 1.4 mm ± 8.8 for distal lateral femoral resection) and hip–knee–ankle axis alignment (0.3 degree ± 1.9 )(p < 0.05) but not for tibial bone cuts. Differences between planned and validated measurements during the learning and proficiency phases were nonsignificant across all parameters, except for the femoral flexion angle (0.42 degree ± 0.8 vs. 0.44 degree ± 2.7) (p = 0.49).ConclusionThe ROSA Knee System can be integrated into surgical workflows after a modest learning curve of 6 to 14 cases. The system demonstrated high accuracy and reproducibility, particularly for tibial bone cuts. Acknowledging the learning curve associated with new robot-assisted TKA technologies is vital for their effective implementation.

Femoral cartilage thickness measured on MRI varies amongindividuals: Time to deepen one of the principles of kinematic alignment in total knee arthroplasty. A systematic review.

Kinematically aligned total knee arthroplasty (KA TKA), as a pure resurfacing procedure, is based on matching implant thickness with bone cut and kerf thickness, plus cartilage wear. However, the assumption of a consistent 2 mm femoral cartilage thickness remains unproven. This study aimed to systematically review the available literature concerning magnetic resonance imaging (MRI) assessment of femoral cartilage thickness in non-arthritic patients. Our hypothesis was that cartilage thickness values would vary significantly amongindividuals, thereby challenging the established KA paradigm of 'one-cartilage-fits-all'. Systematic literature searches (Pubmed, Scopusand Cochrane Library) followed PRISMA guidelines. English-language studies assessing distal and posterior femoral cartilage thickness using MRI in non-arthritic adults were included. Studies lacking numerical cartilage thickness data, involving post-operative MRI, considering total femoro-tibial cartilage thickness, or failing to specify the compartment of the knee being studied were excluded. Overall, 27 studies comprising 8170 MRIs were analysed. Weighted mean femoral cartilage thicknesses were: 2.05 ± 0.62 mm (mean range 1.06-2.6) for the distal medial condyle, 1.95 ± 0.4 mm (mean range 1.15-2.5) for the distal lateral condyle, 2.44 ± 0.5 mm (mean range 1.37-2.6) for the posterior medial condyleand 2.27 ± 0.38 mm (mean range 1.48-2.5) for the posterior lateral condyle. Femoral cartilage thickness varies significantly across patients. In KA TKA, relying on a fixed thickness of 2 mm may jeopardize the accurate restoration of individual anatomy, leading to errors in implant coronal and rotational alignment. An intraoperative assessment of cartilage thickness may be advisable to express the KA philosophy at its full potential. Level IV.

(294) A CASE OF METAL RING ENTRAPMENT CAUSING PENOSCROTAL STRANGULATION

Abstract Introduction Penile “tension rings” have been described as early as the 3rd century in Chinese literature as men were described as wrapping goat eyelids around the base of their penis for increased erection potency. There have been other materials used to prevent blood outflow from the penis during an erection such as rubber bands, plastic bottlenecks, rubber bands, silicone rings, and metal rings. Wearing a penile/penoscrotal constriction device for longer than 30 minutes can lead to serious complications such as tissue edema, ischemia, and eventual necrosis. Thus, if unable to remove a constrictive device, emergent medical intervention is required. Objective We report a case of an otherwise healthy 56 year-old male who presented to the emergency department with a titanium metal ring around his penis and scrotum for 72 hours. Methods We studied the details of patient presentation, our various treatments attempted, and patient outcome at our institution. We additionally performed a literature review on PubMed (keywords: penile ring entrapment, penile ring strangulation, penile ring treatment) to review other treatment options. Results A 56 year-old male with a history of HIV who presented to the emergency department with a titanium metal ring around his penis and scrotum for 72 hours (Fig. 1). Patient was afebrile, hemodynamically stable, and with unremarkable labs. Initial attempts at reducing penoscrotal edema by compression to subsequently slide off the ring using mineral oil were unsuccessful. We then attempted the “string pull” technique by sequentially advancing 0 silk sutures over the ring which was also unsuccessful. We then used an orthopedic bone cutter which was also unsuccessful as the titanium material was too strong. Finally, we resorted to using a Dremel circular rotary saw (which provided to the hospital by the local fire department) to cut the titanium metal ring off in the operating room (Fig. 2). The patient did well post-operatively and passed his trial of void before being discharged on post-operative day one. The patient did not follow up in clinic afterwards. Conclusions Penile ring entrapment is a true urologic emergency. Treatment aims to remove the ring while protecting underlying tissue. Treatment is based on case severity and what tools a physician may have at their respective hospital. Noninvasive techniques such as edema compression, lubricant use, and the “string pull” method. When these noninvasive techniques fail, various bone/bolt cutters or saws may be used. Disclosure No.

Real-world accuracy of robotic-assisted total knee arthroplasty and its impact on expedited recovery.

Despite total knee arthroplasty (TKA) being the gold standard for end-stage knee osteoarthritis, 20% of patients remain dissatisfied. Robotic-assisted arthroplasty promises unparalleled control of the accuracy of bone cuts, implant positioning, control of gap balance, and resultant hip-knee-ankle (HKA) axis. Patients underwent clinical and radiological assessments, including knee CT scans and patient-reported outcome measures (PROMs), preoperatively. Follow-up assessments were conducted at 2weeks, 6weeks, and 3months post-operatively, with imaging repeated at 6weeks. A total of 155 patients underwent robotic-assisted TKA and have completed 3months of follow-up. Mean pre-operative HKA axis was 7.39 ± 5.52 degrees varus, improving to 1.34 ± 2.22 degrees varus post-operatively. Restoration of HKA axis was 0.76 ± 1.9 degrees from intra-operative planning (p < 0.0005). Implant placement accuracy in the coronal plane was 0.08 ± 1.36 degrees (p = 0.458) for the femoral component and 0.71 ± 1.3 degrees (p < 0.0005) for the tibial component. Rotational alignment mean deviation was 0.39 ± 1.49 degrees (p = 0.001). Most patients (98.1%) had ≤ 2mm difference in extension-flexion gaps. PROM scores showed improvement and exceeded pre-operative scores by 6weeks post-surgery. Robotic-assisted knee arthroplasty provides precise control over traditionally subjective factors, demonstrating excellent early post-operative outcomes.Level of evidence Prospective observational study-II.

Correlation Between Planned and Executed Bone Cuts Using Robotics in Total Knee Arthroplasty: A Prospective Study of 500 Patients.

This study evaluated the precision of robotic-arm-assisted total knee arthroplasty (RATKA) in performing bone resection, predicting component size, managing soft tissue tension, and determining postoperative range of motion (ROM). A total of 500 participants were enrolled in this prospective cohort research. The procedures were conducted at a single facility, with a uniform method and implant design. The Cuvis system, a fully automated robot, was utilized for the study. The precise removal of bone at both the tibial and femur sites, the positioning of the implant, and the release of soft tissue were documented and then compared to the preoperative plan. The distal (medial and lateral) femoral cuts had a mean absolute deviation from the plan of 0.23mm, while the posterior (medial and lateral) femoral cuts had a mean absolute difference of 1mm and 1.4mm, respectively. The absolute discrepancies in the medial and lateral tibial cuts are 0.93mm and -0.06mm, respectively. Out of 1000 bone resections, 980 (98%) were within < 1mm from the preoperative plan. The predictions for the sizes of the tibial and femoral components had accuracies of 100% and 98.9%, respectively. These findings collectively underscore the effectiveness of the fully automated Cuvis robotic system in achieving consistent and accurate results in bone resections and implant sizing, highlighting its potential as a valuable tool in orthopedic surgery.

Piezosurgery in endoscopic-assisted trigonocephaly correction: a technical note.

This study aims to evaluate the effectiveness of the Piezosurgery® device in endoscopic-assisted correction of trigonocephaly. Trigonocephaly is a type of craniosynostosis characterized by a triangular-shaped forehead due to the premature fusion of the metopic suture. Traditional open cranial vault reconstruction, although common, is invasive and poses risks. The study explores a less invasive alternative using ultrasonic microvibrations for bone cutting, potentially reducing soft tissue damage and improving surgical outcomes. The Piezosurgery® device was employed in endoscopic trigonocephaly correction surgeries performed on patients under 4months old at the French Referral Center for Craniosynostosis in Lyon. The technique involves making a small skin incision and performing osteotomies from the anterior fontanel to the glabella. A rigid 0° endoscope provides visibility, and the Piezosurgery® device enables precise bone cutting while preserving the dura mater. Post-surgery, patients were discharged within 3days and required to wear a remodeling helmet for 6-8months. The use of Piezosurgery® device allowed precise osteotomies with minimal soft tissue damage. No dura mater injuries occurred in the patient series. The procedure was efficient, with an average duration of 80min, and blood loss was minimal, reducing the need for blood transfusions. The endoscopic approach facilitated shorter surgical times and reduced postoperative infection risks. Enhanced visibility during surgery, due to cavitation effects, improved the accuracy of bone cuts. The technique demonstrated promising safety and esthetic outcomes, although it incurred higher costs compared to traditional methods. Piezosurgery® device provides a safe and effective method for minimally invasive endoscopic correction of trigonocephaly. The device's ability to selectively cut bone while preserving soft tissues offers significant advantages, despite longer surgical times and higher costs. This technique represents a viable alternative to traditional open surgery, promoting better clinical outcomes and reduced recovery times.

Technology in Total Knee Arthroplasty in 2023

Over the past few decades, instrumentation and techniques for total knee arthroplasty have evolved from conventional manual tools to a wide range of technologies, including calibrated guides for accurate bone cuts and alignment, smart tools, dynamic intraoperative sensors for soft tissue balancing, patient-specific guides, computer navigation, and robotics. This review is intended to provide an overview of the latest advancements in total knee arthroplasty technology, address potential challenges and solutions related to the application of these technologies, and explore their limitations.

Tracking of Infectious Diseases and Deadly Injuries through Signs Observed in Excavated Human Skeletons of 2000 BC/Iron Age in Iran.

Throughout history, many wars have occurred for various reasons, and many empires and kings have fallen or many people killed by wars. Wars were not always due to the conquest of the country. in the Iron Age, societies were governed by tribes at the head of the tribe, and war was only for to seize property, slaves, and food. Our research area is the same period as the Medes Kingdom, which included the union of small, large tribes, wars between tribes existed in that period, and their signs can be seen on the remains of the people of that period. Our research is related to human remains from Sagezabad cemetery, Qazvin plain, which dates back to 2000 BC (Iron Age 2 and 3) in Iran. The blows on the remains were very serious and caused death. We have discussed how to kill by "considering the injured body". Our investigation of how people were killed in war based on injury marks and bullet holes in bones, and simulating those injuries to body tissues and organs also, people who had bone cuts from the war and survived and had bone repair and died due to lack of nutrients and infection were also discussed.

Bone cutter, gomco clamp, and plastibell device for circumcision in neonates and infants: A comprehensive review

Bone cutter, gomco clamp, and plastibell device for circumcision in neonates and infants: A comprehensive review