Three-dimensional computed tomography confirmed that the meniscal root attachments and meniscofemoral ligaments are morphologically consistent.

PURPOSE: To clarify the characteristic features of the meniscal root attachments, meniscofemoral ligaments (MFLs), and related osseous landmarks on three-dimensional images using computed tomography. METHODS: Twenty-eight non-paired, formalin-fixed human cadaveric knees were evaluated in this study. The meniscal root attachments were identified and marked. Three-dimensional images were obtained after applying a contrast agent to the entire meniscal surfaces and MFLs, then the morphology of the meniscal root attachments and MFLs, and their positional relationships with osseous landmarks, were analyzed. RESULTS: Parsons' knob divided the medial meniscal anterior root attachment and lateral meniscal anterior root attachment on the anterior portion of the tibial plateau. The medial meniscal posterior root attachment was near the medial intercondylar tubercle. The lateral meniscal posterior root attachment (LMPRA) was closer to the lateral intercondylar tubercle. Both root attachments were near the posterior intercondylar fossa. The positional relationships between the meniscal root attachments and related osseous landmarks were consistent in all specimens. The MFLs originated from the lateral meniscus posterior horn, and the anterior MFL was closer to the LMPRA than the posterior MFL. The posterior MFL originated at approximately the midpoint between the LMPRA and the most posterior margin of the lateral meniscus. CONCLUSION: This study showed that the relationships between the characteristic features of the meniscal root attachments, MFLs, and related osseous landmarks were consistent. The clinical relevance of this study is that it improved understanding of the anatomy of the meniscal root attachments and MFLs.

Morphology of the Insertions of the Superficial Medial Collateral Ligament and Posterior Oblique Ligament Using 3-Dimensional Computed Tomography: A Cadaveric Study.

PURPOSE: To describe the insertions of the superficial medial collateral ligament (sMCL) and posterior oblique ligament (POL) and their related osseous landmarks. METHODS: Insertions of the sMCL and POL were identified and marked in 22 unpaired human cadaveric knees. The surface area, location, positional relations, and morphology of the sMCL and POL insertions and related osseous structures were analyzed on 3-dimensional images. RESULTS: The femoral insertion of the POL was located 18.3 mm distal to the apex of the adductor tubercle (AT). The femoral insertion of the sMCL was located 21.1 mm distal to the AT and 9.2 mm anterior to the POL. The angle between the femoral axis and femoral insertion of the sMCL was 18.6°, and that between the femoral axis and the POL insertion was 5.1°. The anterior portions of the distal fibers of the POL were attached to the fascia cruris and semimembranosus tendon, whereas the posterior fibers were attached to the posteromedial side of the tibia directly. The tibial insertion of the POL was located just proximal and medial to the superior edge of the semimembranosus groove. The tibial insertion of the sMCL was attached firmly and widely to the tibial crest. The mean linear distances between the tibial insertion of the POL or sMCL and joint line were 5.8 and 49.6 mm, respectively. CONCLUSIONS: This study used 3-dimensional images to assess the insertions of the sMCL and POL and their related osseous landmarks. The AT was identified clearly as an osseous landmark of the femoral insertions of the sMCL and POL. The tibial crest and semimembranosus groove served as osseous landmarks of the tibial insertions of the sMCL and POL. CLINICAL RELEVANCE: By showing further details of the anatomy of the knee, the described findings can assist surgeons in anatomic reconstruction of the sMCL and POL.

Morphology of the fibular insertion of the posterolateral corner and biceps femoris tendon.

PURPOSE: To clarify the fibular head insertion of the fibular collateral ligament (FCL), popliteofibular ligament (PFL), and biceps femoris tendon and related osseous landmarks on three-dimensional (3-D) images. METHODS: Twenty-one non-paired, formalin-fixed human cadaveric knees were evaluated in this study. The fibular head insertions of the FCL, PFL and biceps femoris tendon were identified and marked. 3-D images were created, and the surface area, location, positional relationships, and morphology of the fibular insertions of the FCL, PFL, and biceps femoris tendon and related osseous structures were analysed. RESULTS: The fibular head had a unique pyramidal shape, and the relationships of the fibular insertion of the FCL, PFL, and biceps femoris tendon were consistent. The fibular head consists of three aspects: lateral aspect, posterior aspect, and proximal tibiofibular facet. The insertions of the FCL, PFL, and biceps femoris tendon were attached to the centre from the distal side of the lateral aspects of the fibular head, posterior aspect of the fibular styloid process, and lateral aspect surrounding the FCL, respectively. The mean surface areas of the FCL and PFL fibular insertions were 100.1 ± 29.5 and 18.5 ± 7.2 mm2, respectively. CONCLUSION: This study showed that the relationships between the characteristic features of the fibular head and insertions of the FCL, PFL, and biceps femoris tendon were consistent. The clinical relevance of this study is that it improves understanding of the anatomy of the insertions of the PLC and biceps femoris tendon.

Morphology of insertion sites on patellar side of medial patellofemoral ligament.

PURPOSE: The purpose of this study was to clarify the insertion sites on the patellar side of the medial patellofemoral ligament (MPFL). METHODS: A total of 35 nonpaired human cadaveric knees were used in this study. After identification of the MPFL, the insertion sites on the patellar side of the MPFL were marked. Three-dimensional images were created, and the location and morphology of these insertion sites were analysed. RESULTS: The morphology of the insertion sites on the patellar side of the MPFL was consistent. The proximal fibres of the MPFL were inserted to the deep fascia of the vastus medialis obliquus (VMO) and medial margin of the vastus intermedius (VI). The distal fibres of the MPFL were inserted to the medial margin of the patella directly. The insertion lengths of the VMO, VI, and patella were 26.7 ± 5.0, 28.5 ± 4.4, and 18.5 ± 4.4 mm, respectively. The rate of the vertical distance from the superior pole of the patella to the superior edge of the MPFL in relation to the total patellar height was 12 ± 4.4 %. At the distal edge, the rate was 58 ± 9.6 %. CONCLUSION: The insertion sites on the patellar side of the MPFL were consistent. The MPFL inserted into the VMO and VI was significantly longer than into the patella. The clinical relevance of this study is to improve understanding of the anatomy of the insertion sites on the patellar side of the MPFL and the pathophysiology of patellar dislocation.

Morphology of the femoral insertion site of the medial patellofemoral ligament.

PURPOSE: The purpose of this study was to identify the femoral insertion of the medial patellofemoral ligament (MPFL) and related osseous landmarks. METHODS: A total of 31 unpaired human cadaveric knees were studied. The MPFL was identified, and the site of its femoral insertion was marked. Three-dimensional images were created, and the location and morphology of the femoral insertion of the MPFL and related osseous structures were analyzed. RESULTS: The MPFL was identified in all knees. The femoral insertion of the MPFL was elliptical in shape, and the mean surface area was 56.5 ± 16.9 mm(2). The characteristic features of the femoral insertion of the MPFL could not be identified, but the adductor tubercle was clearly identified in all knees. The centre of the femoral insertion of the MPFL was 10.6 ± 2.5 mm distal to the apex of the adductor tubercle on the long axis of the femur, and the position of the insertion site was consistent in all knees. CONCLUSION: The adductor tubercle was clearly identified as an osseous landmark. The femoral insertion of the MPFL was approximately 10 mm distal to the adductor tubercle. These findings may improve understanding of the anatomy of the femoral insertion of the MPFL and may assist surgeons in performing anatomical reconstruction.

Morphology of the femoral insertion of the lateral collateral ligament and popliteus tendon.

PURPOSE: To clarify the femoral insertion of the lateral collateral ligament (LCL) and popliteus tendon (PT) and related osseous landmarks on three-dimensional images. METHODS: Twenty-six non-paired, formalin-fixed human cadaveric knees were evaluated in this study. Femoral insertion of the LCL and PT was identified and marked. Three-dimensional images were created, and the surface area, location, positional relationships, and morphology of the femoral insertion of the LCL, PT, and related osseous structures were analysed. RESULTS: The mean surface areas of the LCL and PT femoral insertions were 55.8 ± 25.0 and 52.5 ± 24.2 mm(2), respectively. Variations in the positional relationships between the LCL and PT insertions (PT inserted parallel and posterior to the LCL insertion to the long axis of the femur) were observed. The lateral epicondyle and popliteal sulcus could be clearly identified as osseous landmarks on three-dimensional images in all knees. Most of the LCL was inserted postero-distal to the apex of the lateral epicondyle, and the PT was inserted at the anterior end of the popliteal sulcus in all knees. CONCLUSION: We observed variation in the positional relationship between the femoral insertion of the LCL and PT. However, the relationships between their insertions and osseous landmarks were consistent. The findings of this study contribute to the understanding of the PLC osseous anatomy and should assist surgeons in performing PLC surgery with a more anatomic perspective.

Morphology of the popliteomeniscal fascicles around the popliteal hiatus on three-dimensional images reconstructed from 7 T magnetic resonance imaging: A cadaveric study.

BACKGROUND: This study aimed to clarify the characteristic features of the anteroinferior and posterosuperior popliteomeniscal fascicles (aiPMF and psPMF, respectively) and popliteal hiatus using three-dimensional (3D) reconstructions of 7 T magnetic resonance imaging (MRI) arthrography. METHODS: Six knees from human cadavers fixed using the Thiel embalming method were examined using 7 T MRI arthrography. 3D Images of the structures around the popliteal hiatus were reconstructed. Morphologies of the psPMF, aiPMF, and popliteal hiatus were investigated and their positional relationships analyzed. RESULTS: The PMFs attached to the periphery of the lateral meniscus (LM) to form the popliteal hiatus. Each coursed in an oblique direction. The mean length of the psPMF and aiPMF attachments to the LM were 6.8 and 21.6 mm, respectively; mean popliteal hiatus length was 12.8 mm. These lengths corresponded to 7.5%, 24.3%, and 14.5% of the total length of the LM, respectively. The aiPMF was thick near the lateral aspect of the articular capsule and became thinner towards the posteromedial aspect of the LM. The psPMF was thick near the posterior aspect of the articular capsule and became thinner towards the posterolateral aspect of the LM. CONCLUSION: Morphological properties of the aiPMF, psPMF, their attachments to the LM, and the popliteal hiatus were consistent across the cadaver specimens examined. Each PMF was thin near the popliteal hiatus and became thicker towards its attachment to the articular capsule. These findings may be useful for anatomical repair for the LM hypermobility.

Morphology of the proximal tibiofibular joint and ligaments using three-dimensional computed tomography: A cadaveric study.

BACKGROUND: The aim of our study was to clarify the morphology of the proximal tibiofibular joint (PTFJ), insertion sites of the proximal tibiofibular ligaments (PTFLs), and related osseous landmarks on three-dimensional (3D) computed tomography (CT) images. METHODS: Cadaveric knees were evaluated by dissection and 3D CT imaging. The anterior PTFL (A-PTFL) and posterior PTFL (P-PTFL) were isolated, and their tibial and fibular insertion sites were identified. The morphology and location of insertion sites and their positional relationships with osseous structures were analyzed on 3D CT images. RESULTS: The A-PTFL comprised up to four bundles, and the P-PTFL comprised two bundles. The mean length of the A-PTFL and P-PTFL was 11.3 mm and 10.3 mm, respectively. On the tibial side of the PTFJ, bony prominences were present at the A-PTFL and P-PTFL insertion sites and were clearly identified as osseous landmarks in all knees. On the fibular side, the A-PTFL and P-PTFL insertion sites were at the edge of the triangular pyramid of the fibular head. The mean PTFJ area was 198.8 mm2, and the mean inclination angle between PTFJ and tibial plane was 38.4°. There was an inverse correlation between the PTFJ surface area and the inclination angle. CONCLUSION: The present study clearly identified PTFL insertion sites on the tibia and fibula and showed the relationships between these insertions and osseous landmarks. These data improve our understanding of the anatomy of PTFL insertions, which may assist surgeons in performing anatomical reconstruction.

Morphology of the quadriceps tendon and its patella insertion site on three-dimensional computed tomography and magnetic resonance imaging: A cadaveric study.

AIM: This study was conducted to clarify the morphological properties of the quadriceps tendon (QT) and its patella insertion site using three-dimensional computed tomography and magnetic resonance imaging. METHODS: Twenty-one right knees from human cadavers were evaluated using three-dimensional computed tomography and magnetic resonance imaging. The morphologies of the QT and its patella insertion site were evaluated, along with intra-tendon differences in length, width, and thickness. RESULTS: The QT insertion site on the patella was dome-shaped without characteristic bony features. The mean surface area of the insertion site was 502.5 ± 68.5 mm2 (range, 336.0-610.7). The QT was longest 2.0 mm lateral to the central width of the insertion and gradually became shorter toward both edges (mean length, 59.7 ± 8.3 mm). The QT was widest at the insertion site (mean width, 39.1 ± 5.3 mm) and gradually became narrower toward the proximal side. The QT was thickest 2.0 mm medial to the center (mean thickness, 11.4 ± 1.9 mm). CONCLUSION: The morphological properties of the QT and its insertion site were consistent. The characteristics of the QT graft depend on the harvested region.

Analysis of characteristics required for gait evaluation of patients with knee osteoarthritis using a wireless accelerometer.

BACKGROUND: Knee osteoarthritis (KOA) is associated with reduced quality of life due to knee pain and gait disturbance. However, the evaluation of KOA is mainly based on images and patient-reported outcome measures (PROMs), which are said to be insufficient for functional evaluation. Recently, gait analysis using an accelerometer has been used for functional evaluation of KOA patients. Nevertheless, evaluation of the entire body motion is insufficient. The aim of this study was to clarify the gait characteristics of KOA patients using the distribution of scalar products and the interval time of heel contact during spontaneous walking and to compare them with healthy subjects. METHODS: Participants wore a three-axis accelerometer sensor on the third lumbar vertebra and walked for 6 min on a flat path at a free walking speed. The sum of a composite vector (CV) scalar product and a histogram for distribution were used for body motion evaluation. The CV consisted of a synthesis of acceleration data from three axes. In addition to the summation of the CV, a histogram can be created to evaluate in detail the magnitude of the waves. The amount of variation was measured in the left-right and front-back directions. Variability was evaluated from the distribution of heel contact duration between both feet measured from the vertical acceleration. RESULTS: KOA patients showed a smaller sum of CV that converged to small acceleration in the distribution when compared with healthy subjects. In the KOA group, the amount of variation in the forward and backward directions was greater than that in the forward direction. The variability of heel-ground interval time was greater in the KOA group than in healthy subjects. CONCLUSION: KOA patients walked with less overall body movement, with limited movable range of the knee joint and pain-avoiding motion. The gait of the KOA group was considered unstable, with long time intervals between peaks. The increase in the amount of forward variation was thought to be due to the effect of trunk forward bending during walking. The clinical relevance of this study is that it was possible to evaluate KOA patients' gait quantitatively and qualitatively.

Characteristic features of the insertions of the distal tibiofibular ligaments on three-dimensional computed tomography- cadaveric study.

PURPOSE: The purpose of this study was to clarify the insertion sites of the anterior inferior tibiofibular ligament (AITFL) and posterior inferior tibiofibular ligament (PITFL) and related osseous landmarks on three-dimensional computed tomography images. METHODS: Twenty-nine non-paired, formalin-fixed human cadaveric ankles were evaluated. The tibial and fibular insertion sites of the AITFL and PITFL were identified. The morphology and location of the insertion sites and their positional relationships with osseous structures were analyzed on three-dimensional computed tomography images. RESULTS: The AITFL had a trapezoidal shape, with fibers that ran obliquely lateral from a wider insertion at the lateral distal tibia to the medial distal fibula. The PITFL had a similar shape to the AITFL; however, it ran more horizontally, with fibers running in the same direction. In the tibia, the anterior capsular ridge and the Chaput's and Volkmann's tubercles were useful osseous landmarks for the insertion sites. In the fibula, the centers of the insertion sites of the AITFL and PITFL were located on the edges of the distal anterior and posterior fibula, which were useful osseous landmarks. The mean distances between the center points of the tibial and fibular insertion sites of the AITFL and PITFL were 10.1 ± 2.4 mm and 11.7 ± 2.6 mm, respectively. CONCLUSIONS: The relationships between the characteristic features of the distal tibia and fibula and the insertions of the AITFL and PITFL were consistent. The present findings improve the understanding of the anatomy of the insertions of the distal tibiofibular syndesmotic joint.

Morphology of the patellar tendon and its insertion sites using three-dimensional computed tomography: A cadaveric study.

BACKGROUND: To clarify, with three-dimensional (3D) images, the morphological properties of the patellar tendon and both of its insertion sites. METHODS: Thirty-two human cadaveric left knees were evaluated, and 3D computed tomography images were created. These images were used to analyse the morphology of both insertion sites of the patellar tendon, and the width, length and thickness of each region of the patellar tendon. RESULTS: The insertion sites of the patellar tendon on the patellar and tibial sides were V-shaped and crescent-shaped, respectively, with the respective bony apexes located at 44.5 ±â€¯2.2% (standard deviation) and 35.5 ±â€¯2.8% of the tendon width from its medial edge. The proximal, central and distal widths of the patellar tendon were 29.9 ±â€¯2.7 mm, 27.3 ±â€¯2.5 mm and 25.0 ±â€¯2.4 mm, respectively. The length of the patellar tendon was shortest at 40.6% ±â€¯6.7% of the central width and gradually became longer toward both edges. The patellar tendon was thickest in the central portion of 40-75% and gradually became thinner toward both edges. CONCLUSIONS: The morphological properties of the patellar tendon and its insertion sites on both the patellar and tibial sides were consistent. These findings indicate that the characteristics of the bone-patellar tendon-bone graft markedly depend on the location from which it is harvested, and that these characteristics contribute to predicting the length, width and shapes of the bone plugs of the graft when performing bone-patellar tendon-bone surgery.