Condyle - Clinical Data
Publications
Safety of, and biological and functional response to, a novel metallic implant for the management of focal full-thickness cartilage defects: Preliminary assessment in an animal model out to 1 year.
Kirker-Head CA, Van Sickle DC, Ek SW, McCool JC.
Tufts Cummings School of Veterinary Medicine, 200 Westborough Road, North Grafton, Massachusetts 01536, USA. carl.kirker-head@tufts.edu
J Orthop Res. 2006 May;24(5):1095-108.
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Abstract
Focal full-thickness cartilage lesions of the human medial femoral condyle (MFC) can cause pain and functional impairment. Affected middle-aged patients respond unpredictably to existing treatments and knee arthroplasty may be required, prompting risk of revision. This study assesses the safety of, and biological and functional response to, a metallic resurfacing implant which may delay or obviate the need for traditional arthroplasty. The anatomic contour of the surgically exposed MFC of six adult goats was digitally mapped and an 11 mm diameter full-thickness osteochondral defect was created. An anchor-based Co-Cr resurfacing implant, matching the mapped articular contour, was implanted. Each goat's contralateral unoperated femorotibial joint was used as a control. Postoperative outcome was assessed by lameness examination, radiography, arthroscopy, synoviocentesis, necropsy, and histology up to 26 (n = 3) or 52 (n = 3) weeks. By postoperative week (POW) 4, goats demonstrated normal range of motion, no joint effusion, and only mild lameness in the operated limb. By POW 26 the animals were sound with only occasional very mild lameness. Arthroscopy at POW 14 revealed moderate synovial inflammation and a chondral membrane extending centrally across the implant surface. Radiographs at POWs 14 to 52 implied implant stability in the operated joints, as well as subchondral bone remodeling and mild exostosis formation in the operated and contralateral unoperated joints of some goats. By POW 26, histology revealed new trabecular bone abutting the implant. At POWs 26 and 52 MFC cartilage was metachromatic and intact in the operated and unoperated femorotibial joints. Proximal tibiae of some operated and unoperated limbs demonstrated limited subchondral bone remodeling and foci of articular cartilage fibrillation and thinning. The chondral membrane crossing the prosthesis possessed a metachromatic matrix containing singular and clustered chondrocytes. Our data imply the safety, biocompatibility, and functionality of the implant. Focal articular damage was documented in the operated joints at POWs 26 and 52, but lesions were much reduced over those previously reported in untreated defects. Expanded animal or preclinical human studies are justified
Effects of a contoured articular prosthetic device on tibiofemoral peak contact pressure: a biomechanical study.
Becher C, Huber R, Thermann H, Paessler HH, Skrbensky G.
Department of Orthopaedic Surgery, Phillips University Marburg, Baldinger Str, 35043 Marburg, Germany. becher.chris@web.de
Knee Surg Sports Traumatol Arthrosc. 2008 Jan;16(1):56-63. Epub 2007 Oct 13.
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Many middle-aged patients are affected by localized cartilage defects that are neither appropriate for primary, nor repeat biological repair methods, nor for conventional arthroplasty. This in vitro study aims to determine the peak contact pressure in the tibiofemoral joint with a partial femoral resurfacing device (HemiCAP, Arthrosurface Inc., Franklin, MA, USA). Peak contact pressure was determined in eight fresh-frozen cadaveric specimens using a Tekscan sensor placed in the medial compartment above the menisci. A closed loop robotic knee simulator was used to test each knee in static stance positions (5 degrees /15 degrees /30 degrees /45 degrees ) with body weight ground reaction force (GRF), 30 degrees flexion with twice the body weight (2tBW) GRF and dynamic knee-bending cycles with body weight GRF. The ground reaction force was adjusted to the living body weight of the cadaver donor and maintained throughout all cycles. Each specimen was tested under four different conditions: Untreated, flush HemiCAP implantation, 1-mm proud implantation and 20-mm defect. A paired sampled t test to compare means (significance, P < or = 0.05) was used for statistical analysis. On average, no statistically significant differences were found in any testing condition comparing the normal knee with flush device implantation. With the 1-mm proud implant, statistically significant increase of peak contact pressures of 217% (5 degrees stance), 99% (dynamic knee bending) and 90% (30 degrees stance with 2tBW) compared to the untreated condition was seen. No significant increase of peak contact pressure was evaluated with the 20-mm defect. The data suggests that resurfacing with the HemiCAP does not lead to increased peak contact pressure with flush implantation. However, elevated implantation results in increased peak contact pressure and might be biomechanically disadvantageous in an in vivo application.
Arthrosurface: tecnica chirurgica nel ginocchio
R. Buda, A. Ferruzzi, R. Ghermandi, M. Cavallo, S. Giannini
Abstract
Le lesioni osteocondrali focali sono evenienze frequenti, in particolare nel ginocchio, a livello dei condili femorali o dell’articolazione femororotulea. Queste lesioni, se non adeguatamente trattate, costituiscono l’avvio di un processo che porta all’instaurarsi di artrosi precoce. Nella maggior parte dei casi risulta quindi necessario ricorrere alla chirurgia per ripristinare una superficie articolare regolare. Le tecniche proposte in letteratura sono numerose, ma il trattamento
delle lesioni osteocondrali focali di grado III o IV di medie o grandi dimensioni rappresenta ancora oggi un problema terapeutico: le tecniche biologiche o di ingegneria tissutale sono maggiormente indicate nei pazienti giovani. Il limite di applicabilità di queste metodiche è fissato a 50 anni; oltre questo limite si ricorre alla chirurgia protesica tradizionale o a quella mini-invasiva. Il sistema HemiCap® si pone nel panorama della chirurgia protesica mini-invasiva come un dispositivo
in grado di ripristinare a livello della sede di lesione una superficie liscia e regolare, che segue la fisiologica curvatura articolare, con i vantaggi di una ridotta invasività e senza precludere l’eventuale ricorso a successive procedure più invasive.Trattandosi di un sistema mini-invasivo, i limiti di applicabilità sono definiti dalle dimensioni della protesi (la protesi deve coprire almeno l’80% della superficie della lesione). Nel ginocchio il sistema è disponibile per l’applicazione a
livello sia dei condili femorali sia dell’articolazione femororotulea.
Tibiofemoral contact mechanics with a femoral resurfacing prosthesis and a non-functional meniscus.
Becher C, Huber R, Thermann H, Tibesku CO, von Skrbensky G.
Orthopaedic Department, Hannover Medical School, Anna-von-Borries-Str. 1-7, 30625 Hannover, Germany. becher.chris@web.de
Clin Biomech (Bristol, Avon). 2009 Oct;24(8):648-54. Epub 2009 Jun 26.
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Increased contact stress with a femoral resurfacing prosthesis implanted in the medial femoral condyle and a non-functional meniscus is of concern for potential deleterious effects on tibiofemoral contact mechanics.Peak contact pressures were determined in seven fresh frozen human cadaveric specimens using a pressure sensitive sensor placed in the medial compartment above the menisci. A knee simulator was used to test each knee in static stance positions (5 degrees/15 degrees/30 degrees/45 degrees) and through 10 dynamic knee flexion cycles (5-45 degrees) with single body weight ground reaction force which was adjusted to the living body weight of the cadaver donor. All specimens were tested in three different conditions: untreated knee (A); flush implantation of a 20mm resurfacing prosthesis (HemiCAP) in the weight bearing area of the medial femoral condyle (B); complete radial tear at the posterior horn of the medial meniscus with the femoral resurfacing device in place (C).On average, flush device implantation resulted in no statistically significant differences when compared to the untreated normal knee. The meniscal tear resulted in a significant increase of the mean maximum peak contact pressures by 63%, 57%, and 57% (all P< or =0.05) at 15 degrees , 30 degrees and 45 degrees static stance positions and 78% (P< or =0.05) through the dynamic knee flexion cycle. No significant different maximum peak contact pressures were observed at 5 degrees stance position.Although the condition of a meniscal tear without the resurfacing device could not be compared, possible effects of reduced meniscal tissue and biomechanical integrity of the meniscus must be considered in an in vivo application
Minimally-invasive arthroscopically-supported unicondylar surface replacement in discrete cartilage defects of the knee joint – initial results with the Arthrosurface® system
O. Meyer; and E. G. Godolias
Journal of Bone and Joint Surgery - British Volume, Vol 92-B, Issue SUPP_II, 325, 2010.
Publisher Abstract: http://proceedings.jbjs.org.uk/cgi/content/abstract/92-B/SUPP_II/325-b
Abstract
The treatment of discrete but advanced cartilage damage to the knee joint, such as in osteonecrosis in patients older than 45 years, has not been satisfactorily resolved to date. The objective of this prospective study was to investigate the utility of a minimally-invasive unicondylar surface replacement system and to record the first clinically-obtained results. We are reporting on the results of the first 19 operations of discrete knee joint defects performed in our clinic since October 2004 using the Arthrosurface System. The Arthrosurface System consists of specially-preformed convex implantat dowels and an adapted integrative fraise system for handling the femur condylus. The knee joint function, the activity level and the patient’s quality of life were evaluated pre–and postoperative using the Knee Society Score, the Tegner Activity Index and the Lysholm Score. In the operating room, the system was impressive in its utility. No implantat-related complications have occurred in the short follow-up time thus far. In the early postoperative phase, the patients achieved rapid increase in their activity level which paralleled the reduction in pain relief attained. The Arthrosurface® System shows beneficial properties for treating localized but advanced cartilage damage to the knee joint of patients older than 45 years of age. In particular, it enables arthroscopically-supported minimally-invasive implantation. Intact structures are thus not damaged and the patient rehabilitation is rapid.
Treatment of Focal Full Thickness Cartilage Lesions of the Femoral Condyle in Middle-Aged Patients. Comparison of Biological Procedures to Focal Prosthetic Inlay Resurfacing. Arthrosurface 2010
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Related Poster Presentation, ISAKOS 2011, Rio de Janeiro, Brazil
Abstract
Introduction: Middle-aged patients have been shown to achieve significantly lower clinical improvement after focal biological cartilage treatment options compared to younger patients. The objective of this study was to compare prospectively collected outcomes in patients (> 35 years) with focal, full thickness articular cartilage lesions of the femoral condyle. One cohort was treated with biological procedures (BIO), the other underwent prosthetic focal articular inlay resurfacing (CAP).
Materials and Methods: Both cohorts included patients with a full thickness, focal articular cartilage lesion of the medial or lateral femoral condyle which was treated with either a biological procedure or with a HemiCAP® Focal Femoral Condyle Resurfacing Prosthesis. All patients had preoperative and 2 year follow-up data. Comparative cohort parameters included age, gender, BMI, smoking status, lesion location, diameter, procedure failure, associated pathology, subsequent surgery, and adverse events. Both studies used WOMAC (normalized scale from 0-100, 100=best), SF-12 and satisfaction data. Success for both cohorts was defined as the minimum clinically important difference of 20% improvement (MCID-20) on Pain and Function WOMAC sub-domains at 2 years compared to baseline and no additional defect or device related surgical intervention.
Results: Thirty patients were included in BIO group and 32 in the CAP group. Patients in both groups were similar in all aspects of their demographics and lesions. Patients were followed on average for 2.55 years in BIO and 2.0 years in CAP. Fifty-three percent (n=16/30) of the BIO patients were considered a success vs. 75% (n=24/32) in the CAP group. There were 4/30 secondary defect or device related procedures in the BIO group and 2/32 in the CAP group. At last follow-up, combined MCID-20 levels for WOMAC Pain and Function were achieved by 63% (n=19/30) in the BIO Group and by 78% (n=25/32) in the CAP Group (p=0.20599). For all WOMAC domains, patients in the CAP group were worse, more symptomatic at baseline, but higher (better) on their post-op scores compared to patients in the BIO group. In the BIO Group, the mean Total WOMAC score significantly improved from 57.91 to 78.04, in the CAP Group, the mean Total WOMAC score significantly improved from 42.05 to 86.40. Physical (not mental) subcomponent scores (SF-12 PCS) showed a significant improvement in both groups. Conclusion: The results of this study showed significant improvement for both cohorts with a higher success rate for focal prosthetic resurfacing based on the study endpoint definition. Limitations of this study are that this is a cohort study and not a prospective comparison of two identical groups of patients. Based on 2 year comparative data, results support the concept of focal prosthetic inlay resurfacing as a new treatment option in the continuum of care for isolated defects of the femoral condyle effectively adding to the range of biological procedures. Continuation of localized treatment in middle aged patients provides significant joint preservation benefits in the long term management of knee arthrosis and arthritis.
Effects of a surface matching articular resurfacing device on tibiofemoral contact pressure: results from continuous dynamic flexion-extension cycles.
Becher C, Huber R, Thermann H, Ezechieli L, Ostermeier S, Wellmann M, von Skrbensky G.
Orthopaedic Department, Hannover Medical School, Anna-von-Borries-Str. 1-7, 30625, Hannover, Germany. becher.chris@web.de
Arch Orthop Trauma Surg. 2011 Mar;131(3):413-9. Epub 2010 Oct 22.
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The application of a defect-size metal implant for the treatment of focal articular cartilage lesions of the femoral condyle is of potential concern resulting in cartilage damage to opposing biological structures. This in vitro study aims to determine the tibiofemoral contact pressure with a contoured articular partial femoral resurfacing device under continuous dynamic pressure loads. Peak and area contact pressures were determined in eight fresh-frozen cadaveric specimens using a pressure-sensitive sensor placed in the medial compartment above the menisci. All knees were tested in the untreated condition and after implantation of the prosthetic device in the weight-bearing area of the medial femoral condyle. A robotic knee simulator was used to test each knee under continuous pressure load for 400 s during 40 dynamic knee bending cycles (5°-45° flexion) with body weight ground reaction force (GRF). The GRF was adjusted to the living body weight of the cadaver donor and maintained throughout all cycles.Comparison of the untreated condition to focal inlay resurfacing showed no statistically significant differences (P ≤ 0.05) between all testing conditions. The average maximum peak contact pressure across all 40 flexion cycles increased by 5.1% after resurfacing compared to the untreated knees. The average area contact pressure essentially stayed the same (+0.9%).The data suggest that resurfacing with the contoured articular prosthetic device does not pose any immediate deleterious effects to the opposing surfaces based on peak and area contact pressure in a continuous dynamic in vitro application. However, long-term in vivo effects remain to be evaluated.
Minimum 5-year results of focal articular prosthetic resurfacing for the treatment of full-thickness articular cartilage defects in the knee.
Becher C, Kalbe C, Thermann H, Paessler HH, Laprell H, Kaiser T, Fechner A, Bartsch S, Windhagen H, Ostermeier S.
Department of Orthopaedic Surgery, Hannover Medical School, Anna-von-Borries-Strasse 1-7, Hannover, Germany. becher.chris@web.de
Arch Orthop Trauma Surg. 2011 Aug;131(8):1135-43. Epub 2011 Jun 4.
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The purpose of this study was to evaluate the results of a contoured focal articular femoral condyle resurfacing prosthetic in the treatment of full-thickness cartilage and osteochondral defects at the medial femoral condyle of the knee beyond 5 years. In a multicenter case series, preoperative and follow-up scores of the Knee Injury and Osteoarthritis Outcome Score (KOOS), SF-36 and Tegner activity scale were evaluated. Standard radiographs were performed to evaluate the progression of osteoarthritis. Patients were also asked to report their satisfaction. A total of 21 patients were included in this study. The average follow-up was 5.3 years. The average age at the time of resurfacing was 54 years. Average KOOS scores significantly (P ≤ 0.005) improved for pain (51.1 to 77.6), symptoms (57.9 to 79.5), activities of daily living (ADL) (58.8 to 82.4), sports (26.3 to 57.8) and quality of life (QOL) (34.4 to 55.0). The Tegner activity level improved significantly (P ≤ 0.02) from 2.9 to 4. The physical health value of the SF-36 increased by 15.2 to 46.9 compared to the preoperative value. The mental health value almost (51.2) remained unchanged. As many as 16/21 of the patients in this series were satisfied with their outcome and would have the operation again. Radiographic results demonstrated solid fixation, preservation of joint space and no change in the osteoarthritic stage. The device appears to be an effective reconstructive treatment option for large full-thickness cartilage and osteochondral lesions of the knee in middle-aged patients.
Current State of Focal Prosthetic Resurfacing of the Femoral Condyles: review of Basic Science and Midterm Clinical Updates. Arthrosurface 2011
Uribe J, Schepsis A, Bollars P, Bosquet M, Becher C, Paessler H, Miniaci A
Abstract
Full thickness cartilage defects of the femoral condyles are frequent, can be highly symptomatic, and pose treatment challenges when encountered in middle-aged patients. Biological procedures are plentiful but are more effective in younger than older patients. Standard arthroplasty should be delayed in patients with isolated defects to foster joint preservation. The purpose of this report is to provide an overview on basic science and clinical evidence of focal prosthetic inlay resurfacing. Preclinical results from a caprine model, finite element analysis, static and dynamic robotic transarticular pressure testing, and mid-term clinical assessment are reviewed.
Basic science and clinical outcomes at two and three years show significant benefits of focal resurfacing in middle aged patients. Patient selection and correct placement recessed to the surrounding healthy cartilage surfaces are crucial parameters for successful outcomes. The procedure adds a new layer to reconstructive treatment options in the long-term management of arthrosis and arthritis and allows for a sound clinical exit strategy into standard arthroplasty.
