INTRODUCTION The menisci play a fundamental biomechanical role in the knee and also help in the m... more INTRODUCTION The menisci play a fundamental biomechanical role in the knee and also help in the maintaining of the articular homeostasis; thus, either a lesion or the complete absence of the menisci can invalidate the physiological function of the knee causing important damages, even at long term. Unfortunately, meniscal tears are often found during the ordinary orthopaedic practice while the regenerative potential of this kind of tissue is very low and limited to its peripheral-vascularized part; this is why the majority of these common arthroscopic findings are not reparable and often the surgeon is almost forced to perform a partial, subtotal or even total meniscectomy, regardless of the well-known consequences of this kind of surgery. MATERIALS AND METHODS Recently a porous, biodegradable scaffold made of an aliphatic polyurethane (Actifit(tm),Orteq Ltd) has been developed for the arthroscopic treatment of partial and irreparable meniscal tears; thanks to its particular structure, this scaffold facilitates the regeneration of the removed meniscal part, preventing the potential cartilage damage due to its complete or partial lack. We performed a prospective clinical study on 17 patients affected by a massive loss of meniscal substance either medial or lateral associated with intraarticular or global knee pain and/or swelling. We analyzed the patient both clinically and by using the International Knee Document Committee9s (IKDC) Subjective and Objective Knee Evaluation Form. We also assessed the sport activity resumption by comparing the Tegner score at the time of the very first visit with the presurgery and prelesional ones. Finally, we also organized a control MRI at 6 and 12 months after surgery. DISCUSSION Our preliminary results are encouraging and they confirm the clinical experiences of other study groups. Apparently, the properties of this scaffold help in vessels formation and tissue regeneration potentially allowing the restoration of the surgically removed portion and preventing, or delaying at least, both chondral and articular degeneration. We also performed some biopsy associated arthroscopic “second-looks” that reinforced the already good clinical results; the biopsies also confirmed the new tissue ingrowth into the biomaterial, potentially leading to the replacement of the previously removed damaged tissue. CONCLUSIONS Preliminary results suggest that this surgical procedure can be considered a really promising method for the treatment of both inveterate and symptomatic meniscal tears; however, other randomized studies with a longer follow-up should be done to confirm its reliability and potentialities.
Surgical navigation systems are currently used to guide the surgeon in the correct alignment of t... more Surgical navigation systems are currently used to guide the surgeon in the correct alignment of the implant. The aim of this study was to expand the use of navigation systems by proposing a surgical protocol for intraoperative kinematics evaluations during knee arthroplasty. The protocol was evaluated on 20 patients, half undergoing unicondylar knee arthroplasty (UKA) and half undergoing posterior-substituting, rotating-platform total knee arthroplasty (TKA). The protocol includes a simple acquisition procedure and an original elaboration methodology. Kinematic tests were performed before and after surgery and included varus/valgus stress at 0 and 30 degrees and passive range of motion. Both UKA and TKA improved varus/valgus stability in extension and preserved the total magnitude of screw-home motion during flexion. Moreover, compared to preoperative conditions, values assumed by tibial axial rotation during flexion in TKA knees were more similar to the rotating patterns of UKA knees. The analysis of the anteroposterior displacement of the knee compartments confirmed that the two prostheses did not produce medial pivoting, but achieved a postoperative normal behavior. These results demonstrated that proposed intraoperative kinematics evaluations by a navigation system provided new information on the functional outcome of the reconstruction useful to restore knee kinematics during surgery.
Background Anterior cruciate ligament reconstruction surgery and technique have changed over the ... more Background Anterior cruciate ligament reconstruction surgery and technique have changed over the past decade. Hypothesis Modern arthroscopic management of an anterior cruciate ligament tear using patellar tendon autograft offers a high Patient satisfaction rate and good clinical results over the long term. However, it may be associated with osteoarthritis changes over time. Study Design Case series; Level of evidence, 4. Methods In 1992, a prospective computerized database of anterior cruciate ligament reconstruction was established. Since that time, 101 anterior cruciate ligament arthroscopic reconstructions performed at our institution have been observed. Inclusion criteria were as follows: reconstruction with bone-patellar tendon-bone graft, a minimum 10-year follow-up, a standardized operative procedure, and no previous anterior cruciate ligament repair or associated ligament lesions. Before surgery, the mean age of the patients was 28.8 years ± 8.3 (mean ± SD). The follow-up as...
Summary Autologous chondrocyte implantation (ACI) is an effective means of treating symptomatic a... more Summary Autologous chondrocyte implantation (ACI) is an effective means of treating symptomatic articular cartilage defects. This two-stage cartilage repair strategy relies on the cultured expansion of harvested chondrocytes; these cells are subsequently reimplanted into the host defect ...
Surgical navigation systems are currently used to guide the surgeon in the correct alignment of t... more Surgical navigation systems are currently used to guide the surgeon in the correct alignment of the implant. The aim of this study was to expand the use of navigation systems by proposing a surgical protocol for intraoperative kinematics evaluations during knee arthroplasty. The protocol was evaluated on 20 patients, half undergoing unicondylar knee arthroplasty (UKA) and half undergoing posterior-substituting, rotating-platform total knee arthroplasty (TKA). The protocol includes a simple acquisition procedure and an original elaboration methodology. Kinematic tests were performed before and after surgery and included varus/valgus stress at 0 and 30 degrees and passive range of motion. Both UKA and TKA improved varus/valgus stability in extension and preserved the total magnitude of screw-home motion during flexion. Moreover, compared to preoperative conditions, values assumed by tibial axial rotation during flexion in TKA knees were more similar to the rotating patterns of UKA kne...
Introduction: Several in vitro and in vivo studies have found correspondence between transepicond... more Introduction: Several in vitro and in vivo studies have found correspondence between transepicondylar axis (TEA) and mean helical axis (MHA) in healthy subjects. In addition some studies suggest that the use of MHA for rotational alignment of femoral implant may be more accurate than TEA. Ostheoarthritis (OA) may modify limb alignment and flexion axis, introducing a bias during kinematic acquisition. An in-vivo study comparing normal and osteoarthritic knees using MHA is still lacking. The purposes of this study were: to understand whether arthritis affects somehow the functional axis evaluation and then to assess whether the MHA could be considered as reference flexion axis also for osteoarthritic knees; starting from hypothesis that there is a correspondence between TEA and MHA, to evaluate whether in pathologic subjects there still is the same correspondence. Material and Methods: We included a group of 15 OA patients undergoing TKA and, as control group, 60 patients that underwent ACL reconstruction, since in vivo studies reported small differences in kinematics between ACL reconstructed and uninjured limbs. With a surgical navigation system we recorded intraoperative kinematic data of different passive ranges of motion (PROM) and calculated the MHA applying a least square approach to the set of finite helical axes (FHA) obtained in three different ranges of motion (0°–120°; 35°–80°; 35°–120°). We compared the difference in orientation of MHA in the three ranges with respect to the TEA on frontal (XZ) and axial (XY) planes. The correlation of preoperative limb deformity with MHA-TEA angle was also performed. Results: The results of difference of MHA-TEA angle between the OA and ACL groups for all the three ranges of flexion and in XZ and XY views showed no statistical difference (p=0.5188; p=0.7147 respectively). No statistical difference was found also about MHA-TEA angle between the three ranges in frontal and axial views (ANOVA p=0.6373; p=0.4183 respectively). There was no difference between the flexion and extension movements in the three ranges. We also found that correlation between limb alignment and MHA-TEA angle showed good correlation (r>0.54, p Conclusions: Our work has demonstrated that pathologic knees shows no differences in MHA orientation compared to nearly healthy subjects, moreover there is the same correspondence between TEA and MHA both in XZ and XY plane. We also found that preoperative limb alignment does not correlate with MHA-TEA angle. results are in agreement to studies on healthy subjects. Therefore the MHA may be considered a reliable reference for determining femoral flexion axis and a useful tool in the determination of femoral implant positioning on axial plane, even in surgical setup on osteoarthritic patients.
The objective of this study was to quantify, in vivo, the reduction of knee laxity obtained by an... more The objective of this study was to quantify, in vivo, the reduction of knee laxity obtained by an extra-articular procedure, added to hamstring single-bundle (SB) anterior cruciate ligament (ACL) reconstruction in controlling coupled tibial translation during the Lachman and drawer tests. Twenty-eight patients were evaluated with a computer-assisted kinematic evaluation protocol; patients with associated ligament tears or meniscal damages were not included in the study. All patients underwent an hamstring ACL with an additional extra-articular procedure. During the intervention, tibia was tracked during the Lachman and drawer tests with ACL-deficient knee, after SB fixation and after extra-articular plasty fixation, performed with the remnant part of the hamstring tendons, from end of lateral condyle to Gerdy's tubercle. Statistical analysis was performed to see whether there was a difference in knee laxity after the tests in the three steps. At 30 degrees , the SB graft reduces...
A total of 22 cases of Kinemax prostheses implanted consecutively from January to June 1990 for t... more A total of 22 cases of Kinemax prostheses implanted consecutively from January to June 1990 for the treatment of primary gonarthrosis were evaluated; in these cases remodeling of the patella was performed, and the corresponding component of the prosthesis was not used. The mean age of the patients was 64 years, mean follow-up was obtained after 48 months. According to the HSS form results were: excellent: 9 (40.9%); good: 12 (54.5%); fair: 1 (4.6%). The postoperative femorotibial axis measured a mean of 173.8 degrees. There were no complications in the patella, only in 1 case did we observe mild anterior pain. Knee arthroplasty without substitution of the patella seems to guarantee good results in patients with primary gonarthrosis, as long as patellar reconstruction is performed and correct femoropatellar alignment is guaranteed, as well as recovery of the femorotibial axis with accurate positioning of the prosthetic components.
Radio-Stereometric-Analysis and x-ray fluoroscopy are radiological techniques that require dedica... more Radio-Stereometric-Analysis and x-ray fluoroscopy are radiological techniques that require dedicated software to process data. The accurate calibration of these software is therefore critical. The aim of this work is to produce a protocol for evaluating the softwares' accuracy according to the ISO-5725. A series of computer simulations of the radiological setup and images were employed. The noise level of the images was also changed to evaluate the accuracy with different image qualities. The protocol was tested on a custom software developed by the authors. Radiological scene reconstruction accuracy was of (0.092 +- 0.14) mm for tube position, and (0.38 +- 0.31) mm / (2.09 +- 1.39) deg for detectors oriented in a direction other than the source-detector direction. In the source-detector direction the accuracy was of (2.68 +- 3.08) mm for tube position, and of (0.16 +- 0.27) mm / (0.075 +- 1.16) deg for the detectors. These disparate results are widely discussed in the literatur...
A tissue engineering, cell-based therapeutic approach could be essential for extensive bone or ca... more A tissue engineering, cell-based therapeutic approach could be essential for extensive bone or cartilage reconstruction. This article is divided in two chapters and describes new cell-based surgical techniques for cartilage and bone reconstruction. The second part of the article, regarding cartilage repair, describes a new arthroscopic surgical technique for tissue engineered cartilage grafting. A 3-dimensional hyaluronic acid support is used for autologous chondrocyte culturing. The technique reduces morbidity of classic autologous implant avoiding open surgery and periosteal flap use. With this technique is possible to reduce the patient morbidity, time and cost of surgery.
In transverse and longitudinal paraffin-embedded sections, the human anterior cruciate ligament (... more In transverse and longitudinal paraffin-embedded sections, the human anterior cruciate ligament (ACL) is made up of wavy bundles of collagen fibres arrayed in various directions, the majority around the axis of the ligament with a few running parallel to it. The fascicles making up the larger bundles are also characterised by this undulating appearance. In thin sections 2 types of collagen fibrils are observed: small (with a single diameter peak at 45 nm) and large (3 peaks at 35, 50 and 75 nm respectively), organised into distinct areas made up of either large or small bundles of fibrils. The numerous fibroblasts that are present appear elongated in the direction of the bundles with branches and short cytoplasmic processes. The elastic system is made up of both elastic and oxytalan fibres. The varied orientation of the bundles in the ACL, the complex ultrastructural organisation and the abundant elastic system make it very different from other ligaments and tendons, providing a str...
INTRODUCTION The menisci play a fundamental biomechanical role in the knee and also help in the m... more INTRODUCTION The menisci play a fundamental biomechanical role in the knee and also help in the maintaining of the articular homeostasis; thus, either a lesion or the complete absence of the menisci can invalidate the physiological function of the knee causing important damages, even at long term. Unfortunately, meniscal tears are often found during the ordinary orthopaedic practice while the regenerative potential of this kind of tissue is very low and limited to its peripheral-vascularized part; this is why the majority of these common arthroscopic findings are not reparable and often the surgeon is almost forced to perform a partial, subtotal or even total meniscectomy, regardless of the well-known consequences of this kind of surgery. MATERIALS AND METHODS Recently a porous, biodegradable scaffold made of an aliphatic polyurethane (Actifit(tm),Orteq Ltd) has been developed for the arthroscopic treatment of partial and irreparable meniscal tears; thanks to its particular structure, this scaffold facilitates the regeneration of the removed meniscal part, preventing the potential cartilage damage due to its complete or partial lack. We performed a prospective clinical study on 17 patients affected by a massive loss of meniscal substance either medial or lateral associated with intraarticular or global knee pain and/or swelling. We analyzed the patient both clinically and by using the International Knee Document Committee9s (IKDC) Subjective and Objective Knee Evaluation Form. We also assessed the sport activity resumption by comparing the Tegner score at the time of the very first visit with the presurgery and prelesional ones. Finally, we also organized a control MRI at 6 and 12 months after surgery. DISCUSSION Our preliminary results are encouraging and they confirm the clinical experiences of other study groups. Apparently, the properties of this scaffold help in vessels formation and tissue regeneration potentially allowing the restoration of the surgically removed portion and preventing, or delaying at least, both chondral and articular degeneration. We also performed some biopsy associated arthroscopic “second-looks” that reinforced the already good clinical results; the biopsies also confirmed the new tissue ingrowth into the biomaterial, potentially leading to the replacement of the previously removed damaged tissue. CONCLUSIONS Preliminary results suggest that this surgical procedure can be considered a really promising method for the treatment of both inveterate and symptomatic meniscal tears; however, other randomized studies with a longer follow-up should be done to confirm its reliability and potentialities.
Surgical navigation systems are currently used to guide the surgeon in the correct alignment of t... more Surgical navigation systems are currently used to guide the surgeon in the correct alignment of the implant. The aim of this study was to expand the use of navigation systems by proposing a surgical protocol for intraoperative kinematics evaluations during knee arthroplasty. The protocol was evaluated on 20 patients, half undergoing unicondylar knee arthroplasty (UKA) and half undergoing posterior-substituting, rotating-platform total knee arthroplasty (TKA). The protocol includes a simple acquisition procedure and an original elaboration methodology. Kinematic tests were performed before and after surgery and included varus/valgus stress at 0 and 30 degrees and passive range of motion. Both UKA and TKA improved varus/valgus stability in extension and preserved the total magnitude of screw-home motion during flexion. Moreover, compared to preoperative conditions, values assumed by tibial axial rotation during flexion in TKA knees were more similar to the rotating patterns of UKA knees. The analysis of the anteroposterior displacement of the knee compartments confirmed that the two prostheses did not produce medial pivoting, but achieved a postoperative normal behavior. These results demonstrated that proposed intraoperative kinematics evaluations by a navigation system provided new information on the functional outcome of the reconstruction useful to restore knee kinematics during surgery.
Background Anterior cruciate ligament reconstruction surgery and technique have changed over the ... more Background Anterior cruciate ligament reconstruction surgery and technique have changed over the past decade. Hypothesis Modern arthroscopic management of an anterior cruciate ligament tear using patellar tendon autograft offers a high Patient satisfaction rate and good clinical results over the long term. However, it may be associated with osteoarthritis changes over time. Study Design Case series; Level of evidence, 4. Methods In 1992, a prospective computerized database of anterior cruciate ligament reconstruction was established. Since that time, 101 anterior cruciate ligament arthroscopic reconstructions performed at our institution have been observed. Inclusion criteria were as follows: reconstruction with bone-patellar tendon-bone graft, a minimum 10-year follow-up, a standardized operative procedure, and no previous anterior cruciate ligament repair or associated ligament lesions. Before surgery, the mean age of the patients was 28.8 years ± 8.3 (mean ± SD). The follow-up as...
Summary Autologous chondrocyte implantation (ACI) is an effective means of treating symptomatic a... more Summary Autologous chondrocyte implantation (ACI) is an effective means of treating symptomatic articular cartilage defects. This two-stage cartilage repair strategy relies on the cultured expansion of harvested chondrocytes; these cells are subsequently reimplanted into the host defect ...
Surgical navigation systems are currently used to guide the surgeon in the correct alignment of t... more Surgical navigation systems are currently used to guide the surgeon in the correct alignment of the implant. The aim of this study was to expand the use of navigation systems by proposing a surgical protocol for intraoperative kinematics evaluations during knee arthroplasty. The protocol was evaluated on 20 patients, half undergoing unicondylar knee arthroplasty (UKA) and half undergoing posterior-substituting, rotating-platform total knee arthroplasty (TKA). The protocol includes a simple acquisition procedure and an original elaboration methodology. Kinematic tests were performed before and after surgery and included varus/valgus stress at 0 and 30 degrees and passive range of motion. Both UKA and TKA improved varus/valgus stability in extension and preserved the total magnitude of screw-home motion during flexion. Moreover, compared to preoperative conditions, values assumed by tibial axial rotation during flexion in TKA knees were more similar to the rotating patterns of UKA kne...
Introduction: Several in vitro and in vivo studies have found correspondence between transepicond... more Introduction: Several in vitro and in vivo studies have found correspondence between transepicondylar axis (TEA) and mean helical axis (MHA) in healthy subjects. In addition some studies suggest that the use of MHA for rotational alignment of femoral implant may be more accurate than TEA. Ostheoarthritis (OA) may modify limb alignment and flexion axis, introducing a bias during kinematic acquisition. An in-vivo study comparing normal and osteoarthritic knees using MHA is still lacking. The purposes of this study were: to understand whether arthritis affects somehow the functional axis evaluation and then to assess whether the MHA could be considered as reference flexion axis also for osteoarthritic knees; starting from hypothesis that there is a correspondence between TEA and MHA, to evaluate whether in pathologic subjects there still is the same correspondence. Material and Methods: We included a group of 15 OA patients undergoing TKA and, as control group, 60 patients that underwent ACL reconstruction, since in vivo studies reported small differences in kinematics between ACL reconstructed and uninjured limbs. With a surgical navigation system we recorded intraoperative kinematic data of different passive ranges of motion (PROM) and calculated the MHA applying a least square approach to the set of finite helical axes (FHA) obtained in three different ranges of motion (0°–120°; 35°–80°; 35°–120°). We compared the difference in orientation of MHA in the three ranges with respect to the TEA on frontal (XZ) and axial (XY) planes. The correlation of preoperative limb deformity with MHA-TEA angle was also performed. Results: The results of difference of MHA-TEA angle between the OA and ACL groups for all the three ranges of flexion and in XZ and XY views showed no statistical difference (p=0.5188; p=0.7147 respectively). No statistical difference was found also about MHA-TEA angle between the three ranges in frontal and axial views (ANOVA p=0.6373; p=0.4183 respectively). There was no difference between the flexion and extension movements in the three ranges. We also found that correlation between limb alignment and MHA-TEA angle showed good correlation (r>0.54, p Conclusions: Our work has demonstrated that pathologic knees shows no differences in MHA orientation compared to nearly healthy subjects, moreover there is the same correspondence between TEA and MHA both in XZ and XY plane. We also found that preoperative limb alignment does not correlate with MHA-TEA angle. results are in agreement to studies on healthy subjects. Therefore the MHA may be considered a reliable reference for determining femoral flexion axis and a useful tool in the determination of femoral implant positioning on axial plane, even in surgical setup on osteoarthritic patients.
The objective of this study was to quantify, in vivo, the reduction of knee laxity obtained by an... more The objective of this study was to quantify, in vivo, the reduction of knee laxity obtained by an extra-articular procedure, added to hamstring single-bundle (SB) anterior cruciate ligament (ACL) reconstruction in controlling coupled tibial translation during the Lachman and drawer tests. Twenty-eight patients were evaluated with a computer-assisted kinematic evaluation protocol; patients with associated ligament tears or meniscal damages were not included in the study. All patients underwent an hamstring ACL with an additional extra-articular procedure. During the intervention, tibia was tracked during the Lachman and drawer tests with ACL-deficient knee, after SB fixation and after extra-articular plasty fixation, performed with the remnant part of the hamstring tendons, from end of lateral condyle to Gerdy's tubercle. Statistical analysis was performed to see whether there was a difference in knee laxity after the tests in the three steps. At 30 degrees , the SB graft reduces...
A total of 22 cases of Kinemax prostheses implanted consecutively from January to June 1990 for t... more A total of 22 cases of Kinemax prostheses implanted consecutively from January to June 1990 for the treatment of primary gonarthrosis were evaluated; in these cases remodeling of the patella was performed, and the corresponding component of the prosthesis was not used. The mean age of the patients was 64 years, mean follow-up was obtained after 48 months. According to the HSS form results were: excellent: 9 (40.9%); good: 12 (54.5%); fair: 1 (4.6%). The postoperative femorotibial axis measured a mean of 173.8 degrees. There were no complications in the patella, only in 1 case did we observe mild anterior pain. Knee arthroplasty without substitution of the patella seems to guarantee good results in patients with primary gonarthrosis, as long as patellar reconstruction is performed and correct femoropatellar alignment is guaranteed, as well as recovery of the femorotibial axis with accurate positioning of the prosthetic components.
Radio-Stereometric-Analysis and x-ray fluoroscopy are radiological techniques that require dedica... more Radio-Stereometric-Analysis and x-ray fluoroscopy are radiological techniques that require dedicated software to process data. The accurate calibration of these software is therefore critical. The aim of this work is to produce a protocol for evaluating the softwares' accuracy according to the ISO-5725. A series of computer simulations of the radiological setup and images were employed. The noise level of the images was also changed to evaluate the accuracy with different image qualities. The protocol was tested on a custom software developed by the authors. Radiological scene reconstruction accuracy was of (0.092 +- 0.14) mm for tube position, and (0.38 +- 0.31) mm / (2.09 +- 1.39) deg for detectors oriented in a direction other than the source-detector direction. In the source-detector direction the accuracy was of (2.68 +- 3.08) mm for tube position, and of (0.16 +- 0.27) mm / (0.075 +- 1.16) deg for the detectors. These disparate results are widely discussed in the literatur...
A tissue engineering, cell-based therapeutic approach could be essential for extensive bone or ca... more A tissue engineering, cell-based therapeutic approach could be essential for extensive bone or cartilage reconstruction. This article is divided in two chapters and describes new cell-based surgical techniques for cartilage and bone reconstruction. The second part of the article, regarding cartilage repair, describes a new arthroscopic surgical technique for tissue engineered cartilage grafting. A 3-dimensional hyaluronic acid support is used for autologous chondrocyte culturing. The technique reduces morbidity of classic autologous implant avoiding open surgery and periosteal flap use. With this technique is possible to reduce the patient morbidity, time and cost of surgery.
In transverse and longitudinal paraffin-embedded sections, the human anterior cruciate ligament (... more In transverse and longitudinal paraffin-embedded sections, the human anterior cruciate ligament (ACL) is made up of wavy bundles of collagen fibres arrayed in various directions, the majority around the axis of the ligament with a few running parallel to it. The fascicles making up the larger bundles are also characterised by this undulating appearance. In thin sections 2 types of collagen fibrils are observed: small (with a single diameter peak at 45 nm) and large (3 peaks at 35, 50 and 75 nm respectively), organised into distinct areas made up of either large or small bundles of fibrils. The numerous fibroblasts that are present appear elongated in the direction of the bundles with branches and short cytoplasmic processes. The elastic system is made up of both elastic and oxytalan fibres. The varied orientation of the bundles in the ACL, the complex ultrastructural organisation and the abundant elastic system make it very different from other ligaments and tendons, providing a str...
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