Aims

Over time, the locking mechanism of Modular Universal Tumour and Revision System (MUTARS) knee arthroplasties changed from polyethylene (PE) to polyether-ether-ketone Optima (PEEK) and metal-on-metal (MoM) in an attempt to reduce the risk of mechanical failure. In this study, we aimed to assess the cumulative incidence of locking mechanism revision for symptomatic instability by type of material, and assess potential associated risk factors.

Aims: The knee is the commonest articular location in osteosarcoma (OS). We study the complications in limb salvage due to OS in knee reconstructions. Methods: In our series of 107 OS for the period 1983–1998, limb salvage procedure was possible in 78 cases and the amputation was necessary in 29 patients. The Knee reconstruction includes 62 cases (39 due to femur OS and 23 due to tibia OS). All cases were treated with preoperative and postoperative chemotherapy. The average follow-up was 87.4 months with a range of 55 to 183 months. Results: Complications in re-constructions due to femur OS:. – Local recurrence 2/39 (5.13%). – Infection 2/39 (5.13%). – Fatigue fracture (7.6%) Complications in tibia re-constructions:. – Local recurrences 3/23 (13%). – Infection 5/23 (21.7%). Patellar tendon tear off 2/23 (8.7%). Fatigue fracture 1/23 (4.35%). Conclusions: The rate of complications in tibia is higher than in femur. The infections in tibia limb salvage are related to skin coverage. The local recurrence in tibia is related to anatomical problems to achieve wide resections

A patient in his thirties developed synovitis with grade 4 chondrolysis and a stiff knee with a fixed flexion deformity between three and six years following PLC and PCL reconstruction using LARS (Ligament Augmentation and Reconstruction System, Corin). There was histologic evidence of foreign body reaction, the knee was painful, swollen and stiff. We did not use any further LARS ligaments for soft tissue reconstructions of the kneein our practice. We commenced a recall programme for all 83 patients patients who underwent a soft tissue knee reconstruction using LARS. Of those contacted, 41 replied (49%) and 16 patients had symptoms (19%) and were investigated further with XRay, MRI and arthroscopy as indicated. We discovered a total of five patients had histologically proven synovitis with foreign body reactions (6%), three of whom had life-changing symptomatic pain, swelling and stiffness with degenerate changes (3.6%). These patients had undergone various reconstructions, including a) PLC only, b) ACL and PCL, c) PCL and PLC and d) ACL, PCL and PLC. A further single case of massive bone cyst formation was noted, following PCL reconstruction using LARS (1.2%)

Aims

Anterior cruciate ligament (ACL) and multiligament knee (MLK) injuries increase the risk of development of knee osteoarthritis and eventual need for total knee arthroplasty (TKA). There are limited data regarding implant use and outcomes in these patients. The aim of this study was to compare the use of constrained implants and outcomes among patients undergoing TKA with a history of prior knee ligament reconstruction (PKLR) versus a matched cohort of patients undergoing TKA with no history of PKLR.

Introduction

Anterior cruciate ligament (ACL) and multiligament knee (MLK) injuries increase the risk of development of knee osteoarthritis and eventual need for total knee arthroplasty (TKA). There is limited data regarding implant use and outcomes in these patients. The aim of this study was to compare the use of constrained implants and outcomes among patients undergoing TKA with a history of prior knee ligament reconstruction (PKLR) to a matched cohort of patients undergoing TKA with no history of PKLR.

Objectives

How to position a unicompartmental knee replacement (UKR) remains a matter of debate. We suggest an original technique based on the intra-operative anatomic and dynamic analysis of the operated knee by a navigation system, with a patient-specific reconstruction by the UKR. The goal of the current study was to assess the feasibility of the new technique and its potential pitfalls.

The presence of an unremovable cemented tibial nail presents a unique challenge for limb salvage reconstructions utilizing a rotating hinge knee. All manufacturers’ designs except Link America incorporate a vertically-oriented rotational channel in the proximal tibia to provide the housing for a rotational axis stem. Such channel placement may be impossible in patients with pre-existing tibial hardware that obliterates the proximal tibial intramedullary canal. The Link America design utilizes a superiorly-projecting rotational stem that articulates with a housing located on the rotational yoke component; however it requires an intramedullary tibial stem for component stabilization. Thus all currently available rotating hinge knees require placement of a stem or a stem equivalent into the tibial intramedullary canal.

We describe a limb salvage case employing a Link America rotating hinge knee with a tibial component incorporating a custom hollow stem in a patient with an unremovable centralized, straight, cemented tibial nail. This reconstruction was required following an intra-articular fracture of a successfully incorporated massive proximal tibial osteoarticular allograft. The allograft had been implanted seven years previously following resection of a proximal tibia osteosarcoma.

This custom device allowed a relatively simple limb salvage reconstruction with good results and only a two day hospital stay.

This custom hollow-stemmed device allowed limb salvage in a situation that otherwise would have required either an amputation or resection of a healed tibial allograft that had successfully incorporated, replacing approximately 50% of the length of the tibia shaft. While rarely required, such an implant can allow a relatively simple and straight-forward functional salvage of an extremity in those patients whose only other choices for limb salvage include much more extensive bone resections and complex reconstructions. The potential for subsequent articular level failure should be considered whenever utilizing an osteoarticular allograft. A cemented, retrograde inserted, intramedullary nail can provide reliable internal fixation of such an allograft. If such fixation is selected, a straight intramedullary nail (as in this case) should be utilized, so that the intramedullary device is centered in the proximal tibia. This will allow for future revision to a total knee with a hollow stemmed tibial component should the need arise.

Purpose of the study: The rate of failure can be high for massive reconstruction prostheses after tumor resection. We studied the causes and possible factors of failure.

Material and methods: The series included 91 patients who underwent surgery from 1972 to 1994 for resection of a bone tumor involving the knee joint. A GUEPAR prosthesis was implanted in all cases for reconstruction (megaprosthesis in 58 cases and composite prosthesis in 33). The extensor system had to be reconstructed in 37 patients. A GUEPAR II implant was used in 73 patients; 48 of these implants had an antirotation system. The analysis was retrospective. Outcome was studied in terms of survival and independent factors predictive of failure unrelated to the tumor.

Results: Mean follow-up was 72 months. At last follow-up, 68 patients were living disease free. There were nine cases of rupture of the extensor system. Preservation of a continuous extensor system at the time of bone resection reduced the risk of rupture (p=0.036). Seven allografts fractured, two loosened, and six became infected. Use of an allograft did not reduce the risk of loosening (p=0.17). Intraxial laxity was observed in 17 patients. Use of an antirotation system was a factor of risk of intraxial laxity (p=0.0023) but not of aseptic loosening. Aseptic loosening was observed in 18 patients: 10 femur reconstruction and 8 tibia reconstruction. The difference was not significant (p=0.6). In all, 104 revisions were required in 53 patients; 36 revisions of the prosthesis, 23 of them for mechanical causes. Overall median survival, excepting tumor-related causes, was 130 months. It was 130 months for femur reconstructions and 117 for tibia reconstructions (p=0.57). Age, length of resection, tumor location, use of an allograft, and use of an antirotation system were not found to be significant prognostic factors for implant survival.

Discussion: As reported by many others, we found that the rate of failure of massive prostheses for infectious and mechanical causes remained high in patients treated for bone tumors involving the knee joint. Survival of massive implants is much lower than that of gliding prostheses.

Conclusion: Technical progress is required to improve the survival of massive implants used for the treatment of bone tumors involving the knee joint.

The February 2025 Sports Roundup. 360. looks at: Long-term outcomes of focal cartilage lesions of the knee; Comparison of early and delayed multiligament knee reconstruction; Platelet-rich plasma does not improve recovery after partial meniscectomy; Patient height and sex predict semitendinosus autograft diameter

The anterolateral ligament (ALL) is considered as an important stabilizer of the knee joint. This ligament prevents anterolateral subluxation of the proximal tibia on the femur when the knee is flexed and internally rotated. Injury of the ALL was not investigated in patients with knee dislocation. The aim of the current research is to study the prevalence and characteristics of ALL injury in dislocated knees. A retrospective review of charts and radiological images was done for patients who underwent multiligamentous knee reconstruction surgery for knee dislocation in our institution from May 2008 to December 2016. Magnetic resonance imaging (MRI) was used to describe the ALL injury. The association of ALL injury with other variables related to the injury and the patient's background features was examined. Forty-eight patients (49 knees) were included. The mean age of the patients was 32.3 ± 10.6 years. High energy trauma was the mechanism of dislocation in 28 (57.1%) knees. Thirty-one knees (63.3%) were classified as knee dislocation (KD) type IV. Forty-five (91.8%) knees had a complete ALL injury and three (6.1%) knees had incomplete ALL injury. Forty (81.6%) knees had a complete ALL injury at the proximal fibres of the ALL, while 23 (46.9%) knees had complete distal ALL injury. None of the 46 (93.9%) knees with lateral collateral ligament (LCL) injury had normal proximal ALL fibres (p = 0.012). Injury to the distal fibres of the ALL, as well as overall ALL injury, were not associated with any other variables (p >0.05). Moreover, all patients with associated tibial plateau fractures (9, 18.4%) had abnormality of the proximal fibres of the ALL (p = 0.033). High grade ALL injury is highly prevalent among dislocated knees. The outcomes of reconstructing the ALL in multiligamentous knee reconstruction surgery should be investigated in future studies

Objectives. Congenital cruciate ligament deficiency is a rare condition that may occur in isolation or in association with longitudinal limb deficiencies such as fibular hemimelia or proximal femoral focal deficiency. Often anomalies of the menisci and their attachments can be very abnormal and impact on surgical management by standard techniques. Arthroscopic surgical knee reconstruction is undertaken to improve symptomatic instability and/or to stabilise and protect the knee for future planned limb lengthening surgery. The aim of this study is to evaluate the arthroscopic findings of patients undergoing surgery for congenital cruciate ligament deficiency, and specifically to determine the frequency and types of meniscal anatomical variations seen in these cases. Methods. Patients undergoing surgery for congenital cruciate ligament deficiency were identified from a prospectively collated database. Diagnosis was confirmed through review of the clinical notes and imaging. Operative notes and 4K saved arthroscopic images and video recordings for these cases were reviewed. Results. Over a six-year period (July 2017 – September 2023), 42 patients underwent surgery for congenital ligament deficiency and tibiofemoral instability (45 surgical episodes). Median age of patients at time of surgery was 10 years (range 4 – 17 years). The most frequent diagnosis was congenital longitudinal limb deficiency syndromes in 27 cases, with the most frequent being fibular hemimelia. Isolated congenital ligament deficiency without any other associated extra-articular manifestations occurred in 11 cases. Absence of meniscal root attachments or hypertrophy of meniscofemoral ligaments acting as ‘pseudo-cruciates’ were seen in over 25% of patients. In isolated ACL deficiency these were injured causing onset of instability symptoms and pain following trauma. Often these abnormal structures required addressing to allow surgical reconstruction. Conclusions. Our findings demonstrate that there are often meniscal variations seen in association with congenital absence or hypoplasia of the cruciate ligaments. In these patients hypertrophied meniscofemoral ligaments may act as cruciate-like structures and play a role in providing a degree of sagittal plane stability to the knee. However, when the knee becomes unstable to the point that cruciate ligament reconstruction is indicated, these meniscal variants may often require stabilisation using complex meniscal root repair techniques or variations to standard cruciate ligament reconstruction techniques to accommodate the variant anatomy

While surgeon-industry relationships in orthopaedics have a critical role in advancing techniques and patient outcomes, they also present the potential for conflict of interest (COI) and increased risk of bias in surgical education. Consequently, robust processes of disclosure and mitigation of potential COI have been adopted across educational institutions, professional societies, and specialty journals. The past years have seen marked growth in the use of online video-based surgical education platforms that are commonly used by both trainees and practicing surgeons. However, it is unclear to what extent the same COI disclosure and mitigation principles are adhered to on these platforms. Thus, the purpose of the present study was to evaluate the frequency and adequacy of potential COI disclosure on orthopaedic online video-based educational platforms. We retrospectively reviewed videos from a single, publicly-accessible online peer-to-peer orthopaedic educational video platform (VuMedi) that is used as an educational resource by a large number of orthopaedic trainees across North America. The 25 highest-viewed videos were identified for each of 6 subspecialty areas (hip reconstruction, knee reconstruction, shoulder/elbow, foot and ankle, spine and sports). A standardized case report form was developed based on the COI disclosure guidelines of the American Academy of Orthopaedic Surgery (AAOS) and the Journal of Bone and Joint Surgery. Two reviewers watched and assessed each video for presentation of any identifiable commercial products or brand names, disclosure of funding source for video, and presenter's potential conflict of interest. Additionally, presenter disclosures were cross-referenced against commercial relationships reported in the AAOS disclosure database to determine adequacy of disclosure. Any discrepancies between reviewers were resolved by consensus wherever possible, or with adjudication by a third reviewer when necessary. Out of 150 reviewed videos, only 37 (25%) included a disclosure statement of any kind. Sixty-nine (46%) videos involved the presentation of a readily identifiable commercial orthopaedic device, implant or brand. Despite this, only 13 of these (19%) included a disclosure of any kind, and only 8 were considered adequate when compared to the presenter's disclosures in the AAOS database. In contrast, 83% of the presenters of the videos included in this study reported one or more commercial relationships in the AAOS disclosure database. Videos of presentations given at conferences and/or academic meetings had significantly greater rates of disclosure as compared to those that were not (41% vs 14%; p=0.004). Similarly, disclosures associated with conference/meeting presentations had significantly greater rates of adequacy (21% vs 7%; p=0.018). Even so, less than half of the educational videos originating from a conference or meeting included a disclosure of any kind, and only about half of these were deemed adequate. No differences were seen in the rate of disclosures between orthopaedic subspecialties (p=0.791). Online orthopaedic educational videos commonly involve presentation of specific, identifiable commercial products and brands, and the large majority of presenters have existing financial relationships with potential for conflict of interest. Despite this, the overall rate of disclosure of potential conflict of interest in these educational videos is low, and many of these disclosures are incomplete or inadequate. Further work is needed to better understand the impact of this low rate of disclosure on orthopaedic education both in-training and in practice

Introduction. The purpose of the study was to determine access to and, ability to use telemedicine technology in an adult hip and knee reconstruction patient population and we seek to understand these patients' perceived benefits, risks and preferences of telemedicine. Methods. We performed a cross-sectional telephone administered survey on patients scheduled to undergo primary THA and TKA by one of six surgeons at a single academic institution between March 23 and June 2, 2020. Results. 163 patients were contacted and 113 (69.3%) completed the survey. Of the patients that completed surveys, 88% of patients reported using the internet with 94% reporting owning a device capable of videoconferencing. 78% of patients had participated in a video call in the past year and 37% having done a video visit with their physician. When asked for their preferred method for a physician visit, 80% ranked in-person as their first choice, followed by 18% preferring a video visit. Perceived benefits of telemedicine visits included reduced travel to appointments (87% agree or strongly agree) and reduced cost of attending appointments (63% agree or strongly agree). However, patients were concerned that they would not establish the same patient-physician connection (51% agree or strongly agree) and would not receive the same level of care (33% agree or strongly agree) through telemedicine visits versus in person visits. Conclusion. The majority of total hip and knee arthroplasty patients have access to and are capable of using the technology required for telemedicine visits. However, patients still prefer to have in person visit over concern that they will not establish the same patient-physician connection and will not receive the same level of care, despite benefits of reduced time spent traveling to and cost of attending appointments, and making it easier to attend appointments

OSSTEC is a pre-spin-out venture at Imperial College London seeking industry feedback on our orthopaedic implants which maintain bone quality in the long term. Existing orthopaedic implants provide successful treatment for knee osteoarthritis, however, they cause loss of bone quality over time, leading to more dangerous and expensive revision surgeries and high implant failure rates in young patients. OSSTEC tibial implants stimulate healthy bone growth allowing simple primary revision surgery which will provide value for all stakeholders. This could allow existing orthopaedics manufacturers to capture high growth in existing and emerging markets while offering hospitals and surgeons a safer revision treatment for patients and a 35% annual saving on lifetime costs. For patients, our implant technology could mean additional years of quality life by revising patients to a primary TKA before full revision surgery. Our implants use patent-filed additive manufacturing technology to restore a healthy mechanical environment in the proximal tibia; stimulating long term bone growth. Proven benefits of this technology include increased bone formation and osseointegration, shown in an animal model, and restoration of native load transfer, shown in a human cadaveric model. This technology could help capture the large annual growth (24%) currently seen in the cementless knee reconstruction market, worth $1.2B. Furthermore, analysis suggests an additional market of currently untreated younger patients exists, worth £0.8B and growing by 18% annually. Making revision surgery and therefore treatment of younger patients easier would enable access to this market. We aim to offer improved patient treatment via B2B sales of implants to existing orthopaedic manufacturer partners, who would then provide them with instrumentation to hospitals and surgeons. Existing implant materials provide good options for patient treatments, however OSSTEC's porous titanium structures offer unique competitive advantages; combining options for modular design, cementless fixation, initial bone fixation and crucially long term bone maintenance. Speaking to surgeons across global markets shows that many surgeons are keen to pursue bone preserving surgeries and the use of porous implants. Furthermore, there is a growing demand to treat young patients (with 25% growth in patients younger than 65 over the past 10 years) and to use cementless knee treatments, where patient volume has doubled in the past 4 years and is following trends in hip treatments. Our team includes engineers and consultant surgeons who have experience developing multiple orthopaedic implants which have treated over 200,000 patients. To date we have raised £175,000 for the research and development of these implants and we hope to gain insight from industry professionals before further development towards our aim to begin trials for regulatory approval in 2026. OSSTEC implants provide a way to stimulate bone growth after surgery to reduce revision risk. We hope this could allow orthopaedic manufactures to explore high growth markets while meaning surgeons can treat younger patients in a cost effective way and add quality years to patients' lives

Acute total knee dislocations are uncommon injuries for which some surgeons use artificial ligaments as their choice of graft for reconstruction. The goal of this study is to evaluate on a short and long term basis the stability and function of the LARS reconstructed knee. Flexion ROM was the only parameter which showed significant difference (p< 0.05) between subgroups. Therefore this treatment option for dislocated knee reconstruction seems to give good and lasting results even though patient’s quality of life may suffer. Although a variety of options have been proposed for the treatment of knee dislocations, the optimal one remains controversial. Allografts and autografts have both been used for reconstruction of the cruciate ligaments. The purpose of this study is to evaluate acute reconstruction of both cruciate ligaments using Ligament Advanced Reinforced System (LARS) artificial ligaments. We reviewed treatment of forty-eight acute knee dislocations. All patients had reconstruction of both cruciate ligaments with LARS ligaments. Patients were assed using SF-36, Lysholm and IKDC questionnaires as well as a physical exam. Stability of the reconstructed knee was evaluated radiologically using TELOS instrumentation. The controlateral knee was used as reference. The forty-eight patients were subdivided into four groups of post-operative intervals ranging from six months to seven years. The average ROM was 120°of flexion and −1.4° of extension. The differential average TELOS for LCA, LCP at 30° and LCP at 90° were respectively 2.9 mm, 2.8 mm, 6.9 mm. and their average Lysholm, SF-36 and IKDC scores were 72.0, 72.5, 53.5. Statistical results showed no significant difference (p> 0.05) between subgroups in terms function, laxity and extension but did in flexion. Our data show that patients treated by this method can regain a functional knee in terms of motion, stability and functional status and does not seem to deteriorate with time. Knee reconstruction with artificial ligaments shows promising results at short and longer term even though it seems to affect quality of life in this population. Financing: This study was partially financed by JK Orthomedic Inc

Introduction. Although total knee replacement became a widespread procedure for the purpose of knee reconstruction, osteotomies around the knee were regularly performed. Total knee arthroplasty should be performed for advanced arthritis of the knee. With the advent of biplanar open wedge high tibial osteotomy (HTO) combined with locking plate fixation, HTO has been expanded and its surgical outcome has been improved in recent years. However, post-operative joint-line obliquity has been raised as a concern with this procedure, which may affect the outcome especially in the knees with severe varus deformity. Hence the purpose of this study is to analyze the compression and shear stresses in the knee cartilage with joint line obliquity after HTO. Methods. Using a three-dimensional computer aided design software, the digital knee model with soft tissues was developed. The geometrical bone data used in this study were derived from commercially available human bone digital anatomy media (3972 and 3976, Pacific Research Laboratories, Inc., WA, USA). The three-dimensional knee model was transferred to finite element model. Material properties of the soft tissues and bones were derived from previous studies. The loading condition was adjusted to the load during a single-leg stance of the gait cycle, which resulted in an axial compressive load of 1200 N. Two different conditions were subjected to the analysis: normal alignment and joint-line obliquity after HTO. For the normal alignment, a static force of 1200 N was applied along the mechanical axis. For the joint-line obliquity models, a single force of 1200 N was applied rotating force directions in the frontal plane from the normal direction by 2.5º, 5º, 7.5º, and 10º, respectively. Results. The maximum values of the axial stresses in the cartilages for the normal condition showed almost same values in medial and lateral compartments. In the joint-line obliquity models, the maximum axial stress values in the medial compartment did not exhibit substantial change up to the level of 7.5º obliquity, while a rise in maximum stress value was observed for the model with 10º obliquity. The shear stress showed a different tendency. In the joint-line obliquity models, a steep rise of laterally directed shear stress in the medial compartment was observed for models with obliquity of 5º or more. Discussion. The shear stress in the medial cartilage increased to almost twice as high as the normal knee level for the joint- line obliquity model with an inclination of 5º. The maximum shear stress values increased in accordance with the obliquity angle. The elevated stress could be deleterious to the cartilage. In such large amount of correction by tibial osteotomy leads to unfavorable mechanical environment in the knee. For those severe situations, double-level osteotomy, which retains anatomical knee joint line by simultaneous femoral and tibial osteotomies, should be considered to correct the joint-line obliquity