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The Bone & Joint Journal
Vol. 107-B, Issue 2 | Pages 239 - 245
1 Feb 2025
Evenhuis RE Bus MPA van Nes J Walter SG Cabrolier J Fiocco M van der Wal RJP Broekhuis D Sellevold S van de Sande MAJ

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.

Methods

The MUTARS Orthopaedic Registry Europe was used for a retrospective review of 316 patients (54% male (n = 170), median age 44 years (IQR 23 to 61)) who underwent a MUTARS knee arthroplasty for oncological indications between December 1995 and January 2023. The minimum follow-up was 12 months, and the median follow-up was 7.9 years (IQR 3.3 to 13.0). A competing risk model was used to estimate the cumulative incidence of first locking mechanism revision with death and revision for any other reason as competing events. Possible risk factors were assessed employing a univariate cause-specific hazards regression model.


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_III | Pages 256 - 256
1 Mar 2004
Majò J Gracia I Escribà I Doncel A
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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


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_7 | Pages 7 - 7
1 May 2018
Rodger M Davis N Griffiths-Jones W Lee A
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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%)


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_12 | Pages 37 - 37
1 Oct 2018
James EW Blevins J Gausden E Turcan S Satalich J Denova T Ranawat AS Ranawat AS Ranawat CS Warren RF
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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.

Methods

All patients with history of ACL or MLK reconstruction who underwent TKA between 2007–2018 were identified in a single institution registry. A matched cohort was identified based on patient age, body mass index (BMI), sex, and year of surgery. The primary outcome measure was utilization of constrained implants. Secondary outcomes included rates of deep vein thrombosis (DVT), pulmonary embolism (PE), infection, postoperative transfusion, postoperative knee range of motion (ROM), revision surgery, and patient reported outcomes (Knee Injury and Osteoarthritis Outcome Score for joint replacement (KOOS, JR).


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_2 | Pages 80 - 80
1 Jan 2016
Jenny J Diesinger Y
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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.

Methods

100 patients were consecutively operated on by implantation of a UKR with help of a well validated, non-image based navigation system, by one single surgeon. There were 41 men and 59 women, with a mean age of 68 years (range, 51 to 82 years). After data registration, the navigation system provided the dynamic measurement of the coronal tibio-femoral mechanical angle in full extension. The reducibility of the deformation was assessed by a manually applied torque in the valgus direction. The patient-specific analysis was based on the following hypotheses: 1) The normal medial laxity in full extension is 2° (after previous studies), 2) there was no abnormal medial laxity (which may be routinely accepted for varus knees) and 3) the total reducibility is the sum of the patient's own medial laxity and of the bone and cartilage loss. We assumed that the optimal correction may be calculated by the angle of maximal reducibility, less 2° to respect the normal medial laxity. The bone resections were performed accordingly to this calculated goal. No ligamentous balance or retension was performed. The fine tuning of the remaining laxity was performed by adapting the height of polyethylene component with a 1 mm step. The final measurements (coronal tibio-femoral angle in full extension and medial laxity in full extension) were performed with the navigation system after the final components fixation. The implantation had to fulfill these two parameters: optimal correction as defined previously, and a 2 ± 1° of medial laxity.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 412 - 412
1 Nov 2011
Ward WG Cooper J
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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.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_II | Pages 240 - 240
1 Jul 2008
BIAU D ANRACT P FAURE F MASCARD E BABINET A DUMAINE V LAURENCE V
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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.


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_8 | Pages 78 - 78
1 Aug 2020
Marwan Y Martineau PA Kulkarni S Addar A Algarni N Tamimi I Boily M
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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


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_18 | Pages 2 - 2
1 Dec 2023
Basheer S Kwaees T Tang C Ali F Haslam P Nicolaou N
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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


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_12 | Pages 94 - 94
1 Dec 2022
Versteeg A Chisamore N Ng K Elmoursi O Leroux T Zywiel M
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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


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_10 | Pages 54 - 54
1 Oct 2020
Freiman S Schwabe M Pashos G Barrack RL Nunley R Adelani M Pascual-Garrido C Clohisy J Lawrie C
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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


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_9 | Pages 11 - 11
1 Jun 2021
Munford M Jeffers J
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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


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 113 - 113
1 Mar 2008
Ranger P Dahan P De Oliveira E Berry G Talbot M Fernandes J
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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


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_5 | Pages 133 - 133
1 Apr 2019
Higa M Nakayama H Yoshiya S
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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


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_8 | Pages 90 - 90
1 May 2014
Duncan C
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Much is made of the role of good judgment in the reduction of error, although it is undeniable that error has a role in the development of such judgment. Hence retrospectives from those with experience have merit if we can assume they have introspection and insight as well. In this panel discussion we will explore the experience of a group of renowned surgeons in the field of hip and knee reconstruction, and we will seek their wisdom on new techniques and technology, honed over a few decades of exciting discovery and oft-times unexpected disappointment. In addition, as the session title suggests, these revered colleagues will be invited to reflect on those they encountered, in person or otherwise, by happenstance or design, who profoundly influenced their careers and how that influence shaped their lives and the lives of those entrusted to their care. “If I have seen further than others, it is by standing upon the shoulders of giants” Sir Isaac Newton


Orthopaedic Proceedings
Vol. 97-B, Issue SUPP_16 | Pages 60 - 60
1 Dec 2015
Giordano G Gracia G Lourtet J Felice M Bicart-See A Gauthie L Marlin P Bonnet E
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To evaluate the value of the use of massive prostheses in periprosthetic infections both in one stage and two stages procedures. Between 2008 and 2014, 236 revisions for PJI had been performed in our hospital by the same surgeon. For the most complex cases, we decided to introduce megaprostheses in our practice in 2011. We report a prospective series of 33 infected patients treated between 2011 and the end of 2014, 14 male and 19 female with on average 67.9 years old (38–85) Infection involved TKA in 22 cases (17 TKA revisions, 4 primary TKA), THA in 9 cases (6 revisions, 3 primary THA), a femoral pseudo-arthrosis with posttraumatic gonarthrosis in one case and a septic humeral pseudoarthrosis in one case. We used a total femoral component for two patients: the first one for a hip PJI with extended diaphyseal bone loss and multiples sinus tracks, and the second one for a massive infected knee prosthesis used in a knee reconstruction for liposarcoma. We used one stage procedures in 20 cases (8 hips, 12 knees, 1 shoulder) and two stages in 13 cases (12 knees and 1 hip). Additional technics included 3 massive extensor system allografts, two local flaps. Perioperative hyperbaric treatment was used for 2 patients. The average follow up is 19.8 months (6–48 months). The most frequent complications were wound swelling and delayed healing in 8 cases;). In 3 cases of one stage surgery a complementary debridement was necessary in the three weeks after the surgery with always a good local and infectious evolution. VAC therapy was used in four cases with good results. We report one early postoperative dead. In summary, the use of massive prostheses in PJI is a good option for complex cases. It can be a good alternative to knee arthrodesis. These components must be used preferentially for older patients, in cases of extreme bone loss or extensive osteomyelitis to secure the bone debridement and the quality of the reconstruction. In our series, the one stage procedure is a validated option even by using complementary technics as bone allografts, extensor system allografts or flaps. We believe the two stages surgery is a secondary option, particularly when soft tissues status is compromised before or after the debridement, and mostly for the knees. The longevity of the implantation must be evaluate by a long term follow up


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_II | Pages 150 - 150
1 Apr 2005
Sefton GK Naguib A Sherief TI
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Purpose: This study was carried out in order to assess the results of reconstruction of a deficient extensor mechanism in the presence of total knee replacement using Connective Tissue Prosthesis (CTP). Methods & results: The CTPs are available as flat tapes constructed from polyester in an open weave structure. They were used to reinforce and reconstruct the extensor mechanism which was deficient in three patients who had undergone total knee replacement or were about to undergo total knee replacement. Two cases had extensor mechanism deficiency as a complication following total knee replacement while the third case had extensor mechanism deficiency at the time of the primary knee reconstruction. The average follow-up was one year. All three cases showed good results with no extension lag and good range of movement at follow up. Conclusion: A Connective Tissue Prosthesis Reconstruction of the knee extensor mechanism offers a good option for the management of the uncommon but difficult problem of extensor mechanism deficiency in patients with a total knee arthroplasty


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXIV | Pages 11 - 11
1 Jul 2012
Sarraf K Atherton D Sadri A Jayaweera A Gibbons C Jones I
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Full-thickness burns around the knee can involve the extensor mechanism. The gastrocnemius flap is well described for soft tissue reconstruction around the knee. We describe a method where a Whichita Fusion Nail¯ knee arthrodesis, combined with a medial gastrocnemius muscle flap was used to salvage the knee and preserve the lower leg following a full-thickness contact burn. The gastrocnemius flap for wound coverage of an open knee joint was originally described in 1970 and remains the workhorse for soft tissue knee reconstruction. There are a number of local alternatives including the vastus lateralis, medialis and sartorius flap; and perforator flaps such as the medial sural artery perforator island flap and islanded posterior calf perforator flap, however many of these are unsuitable for larger defects. Full-thickness burns around the knee can put the extensor mechanism at risk and subsequent rupture is a possible consequence. The gastrocnemius flap has been used to cover a medial knee defect with exposed joint cavity following a burn and also been used in post burn contracture release around the knee. The primary indication for Wichita fusion nail is a failed total knee replacement. It allows intramedullary stabilization with compression at the arthrodesis site to stimulate bone union. With fusion rates reported up to 100% and low complication rates as compared to other methods of fusion, the technique has a useful role in limb salvage type procedures. While use of the gastrocnemius flap in knee burns has been described before we believe this is the first time that this combination of techniques, namely knee arthrodesis with soft tissue reconstruction using a gastrocnemius flap, has been reported. Combining these procedures with a multidisciplinary approach provides a useful alternative leading to limb salvage and avoiding the need for an above knee amputation when extensor reconstruction is not possible


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_III | Pages 415 - 415
1 Jul 2010
Banks J Pengas I Hatcher A Meyers P Sprott D McNicholas M
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The purpose of this study was to evaluate the outcome of posterior cruciate ligament (PCL) reconstruction with a double tunnel technique, using prospective pre & post-operative functional scoring and clinical evaluation. We reviewed those patients who underwent PCL reconstruction between October 2001 and October 2006. 24 patients were identified, 23 male and 1 female. Mean age 30.1 years (range 17–43). Mean follow up 56 months (range 29–86). The commonest mode of injury was football. 3 patients had isolated PCL injuries, 21 had concomitant knee ligament injuries which were treated surgically at the same operation. Patients were prospectively scored pre-operatively and at 3, 6, 12 & 24 months post-op using the Lysholm, IKDC 2000 & KOOS scoring systems. These scores were compared to an injury matched control group who underwent comparable knee ligament reconstructions, but who had intact PCL’s. The knee scores showed a significant improvement in all PCL reconstructed patients post-op (p< 0.05). However, significant differences were found between the PCL reconstructed and PCL intact groups. Both groups had high return to employment and return to sports rates. We describe our method of double tunnel reconstruction. Conclusions: PCL injury is usually associated with concomitant soft tissue knee injuries. PCL deficiency contributes significantly to the morbidity of the multiple ligament injured knee. Reconstruction with the double tunnel technique described gives excellent functional improvement and high rates of return to employment and sports


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XIV | Pages 43 - 43
1 Apr 2012
Manfrini M Colangeli M Staals E Bianchi G Mercuri M
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Aim. The use of megaprostheses for knee reconstruction after distal femur resection in young bone sarcoma patients has become popular since early ′80. The authors reviewed their experience with different distal femur megaprostheses in children. Method. Clinico-radiographic evolution in a consecutive series of 113 children, that had implanted below age 15 (range 6-14) a distal femur megaprosthesis in the period 1984-2007, was analized. A modular implant was used in 97 cases with uncemented femoral stem (three different models along the period). The implant presented fixed-hinge joint in 78 cases while rotating-hinge knee was utilized in 19 cases. In 39 cases the fixed-hinge joint had a tibial component with a polished stem to allow the residual growth of proximal tibia; in two cases a mechanically extendable prosthesis was used. A custom-made noninvasive extendable prosthesis with cemented femoral stem and smooth uncemented tibial stem was used in 15 cases since 2002. Radiological and functional results were analysed and a statistical comparison of implant outcome according different stems was obtained. Results. At a 74 months follow-up (29-294), 72 patients are alive; but 43 of them (60%) had further surgery related to primary implant. Surgical revision rate was 88% (39% for mechanical failure) in long survivors treated before 1995 and 50% (14% with mechanical failure) in more recent cases (p< 0.05). Three long survivors progressed in time to total femur megaprostheses. Five out the 15 cases treated by custom made expandable prostheses were revised before completion of skeletal growth because of implant failure. Conclusion. In limb-salvage for bone sarcoma, megaprostheses are the preferred method to reconstruct distal femur in growing children, but a durable reconstruction is not easy to be achieved. The use of new devices specially addressed to younger patients deserves a serious scientific survey by musculoskeletal oncology community