Background & Methods: The aim of the study is to study the morphometric parameters of cruciate ligaments of the knee joint & clinical relevance in cadaveric study. The specimens used for this investigation consisted originally of the distal part of the femur, the proximal parts of tibia & fibula, & all structures of the knee joint. Results: The bivariate analysis it was found that the PCL proximal width left knee was significantly correlated along ACL proximal width left knee & rest others were insignificantly associated. Conclusion: In conclusion our study demonstrated morphometric parameter of both ACL & PCL & its variation between right & left knees in the Indian population. This can help surgeons make critical decisions concerning graft size, preference for double bundle reconstruction & appropriate position of tunnels in the tibial & femoral counterparts in arthroscopic ACL & PCL reconstruction procedures.
The knee is largest, & one of most complex joints in body. It is a hinge-like joint that is subject to constant impact, flexing, twisting from everyday activities as well as the impact of falls & the effects of arthritis. Injury to knee can significantly affect training & sports performance[1]. The treatment ranges from simple physiotherapy exercises to total knee replacement.
Long articulating bones that form the joint are femur & tibia. The articular surfaces are covered along articular cartilage which provides cushioning & smooth relative motion. The joint is protected anteriorly by patella[2]. Proximal end of patella is connected to quadriceps muscle & the distal portion is connected to anterior tibia through patellar tendon. The hamstring muscles connect to the posterior portion of tibia. Medial, & lateral collateral ligaments connect femur, & tibia on medial, & lateral sides respectively[3]. The anterior, lateral & medial aspects of the extra-articular structure of knee joint. Knee joint is covered by synovial membrane. The synovial fluid fills the synovial chamber. This fluid acts as a lubricant & a carrier of nutrients. The articular surfaces are covered by articular cartilage. A C-shaped tissue called meniscus fits in the space between tibia & femur. It helps to protect the joint & allows the bones to slide freely on each other[4].
The ACL can be divided in distinct functional bundles that represent the varying tension of the fibers through range of motion of knee. The most widely accepted view is the classification of fibers into two bundles, antero-medial & postero-lateral bundles. The bundles are named based on their position of insertion into the tibia. The bundles have a clinical application as well as functional significance. A positive anterior drawer sign is thought to more correspond to a torn antero-medial bundle, whereas a positive Lachman sign is thought to indicate a tear more likely in the postero-lateral bundle. During extension of knee, postero-lateral bundle is stretched & the antero-medial bundle is relaxed[5-7]. The opposite occurs during flexion when femoral attachment of ACL moves into a horizontal position, resulting in stretch of the antero-medial bundle & relaxation of the postero-lateral bundle.
Present study was conducted at Prathima Relief Institute of Medical Sciences, Warangal for 01 Year on 20 cadavers. An incision was made along the knee joint & removes the skin, soft tissues & muscles & cleans it properly. After that the capsule was remove from the posterior aspect of knee, The ACL & PCL were identified & measure in their different parameters. Black ink marker used to outline all the attachments. The length of the ACL measured by the point mark between posterolateral surface of the Intercondylar (IC) notch & anteriorly to the IC eminence. The length of the PCL measured by the point mark between lateral border of the medial femoral condyle & the posterior aspects of the medial & lateral tibial plateau. The width of ACL & PCL measured by their tibial femoral attachment as well as middle portion.
Inclusion Criteria:
Exclusion Criteria:
Fig 1: Specimen showing cruciate ligaments
Fig 2: Proximal width measuring
Fig 3: Central width measuring
Table No. 1: Comparison of the ACL Total Length knee right along left side & PCL Total Length knee right & left side
Parameters |
|
Mean ± SD |
P value |
ACL Total Length (mm)
|
Right Knee
|
29.39 ± 3.66
|
0.64 |
Left Knee
|
29.81 ± 3.03
|
||
PCL Total Length (mm)
|
Right Knee
|
32.16 ± 2.63
|
|
Left Knee
|
31.94 ± 2.80
|
The Comparison of the ACL Total Length right knee along left knee & PCL Total Length right knee & left knee & observed that total length ACL right knee 29.39 ± 3.66 which was insignificantly lower than the total length ACL left knee were 29.81 ± 3.03. While total length PCL right knee 32.16 ± 2.63 which was insignificantly higher than the total length PCL left knee 31.94 ± 2.80. Both ACL & PCL insignificantly associated between right knee & left knee.(P >0.05)
Table No. 2: Comparison of the Proximal, central & distal width ACL
ACL |
|
Mean ± SD |
P value |
Proximal width (mm)
|
Right Knee
|
8.6 ± 0.84
|
0.024 |
|
Left Knee
|
8.5 ± 1.29
|
|
Central width (mm)
|
Right Knee
|
9.2 ± 1.11
|
|
|
Left Knee
|
9.3 ± 1.32
|
|
Distal width (mm) |
Right Knee
|
8.6 ± 0.53
|
|
|
Left Knee
|
8.7 ± 1.34
|
The right knee Proximal, central & distal width ACL along the right knee Proximal, central & distal width PCL & we noted the ACL proximal width of right knee 8.6 ± 0.84 was significantly higher than the PCL proximal width of right knee 8.5 ± 1.29. While central & distal width ACL right knee 9.2 ± 1.11 & 8.6 ± 0.53 respectively were significantly lower than the central. (p <0.05).
Table No. 3: Comparison of the Average width of ACL & Average width of PCL
Parameters |
|
Mean ± SD |
P value |
Average width of ACL (mm)
|
Right Knee
|
8.4 ± 0.66
|
0.017 |
Left Knee
|
9.1 ± 1.14
|
||
Average width of PCL (mm)
|
Right Knee
|
9.4 ± 1.11
|
|
Left Knee
|
9.9 ± 1.33
|
The average width of ACL right knee along left knee & average width of PCL right knee along left knee & we observed that the average width of ACL right knee 8.4 ± 0.66 were significantly lower than the average width of ACL left knee 9.1 ± 1.14. But average width of PCL right knee 9.4 ± 1.11 was insignificantly lower than the average width of PCL left knee 9.9 ± 1.33 (p<0.05).
Table No. 4: Association between ACL proximal width of Knee & PCL proximal width of Knee of both left & right
Parameters |
ACL Proximal Width Right Knee
|
ACL Proximal Width Left Knee
|
PCL Proximal Width Right Knee
|
0.284
|
0.361
|
PCL Proximal Width Left Knee
|
0.578
|
0.047
|
In this table on applying the bivariate analysis it was found that the PCL proximal width left knee was significantly correlated along ACL proximal width left knee & rest others were insignificantly associated.
The site of the attachment of ACL is on the anterior condylar area of tibia along the relation of partly along lateral meniscus. ACL provides stability to the knee joint & acts as passive restrain for the tibia in the respect of femur & prevent the hyperextension of the knee joint. Therefore the incidence of injury of ACL is higher than the other ligaments of knee[8]. The other most important ligament is PCL which is active & primary stabilizer of the knee joint because it acts as principal restrain against posterior tibial translation.
PCL is made up of two bundles, Anterolateral which is larger, stiffer & tighter in flexion. Another bundle is posteromedial which is smaller, short & taut in extension.. It has low incidence of injury than the ACL. therefore it occurring more frequent in traumatic patients.Error! Bookmark not defined[9]. During the surgical repair of cruciate ligaments, the orthopedic surgeon should have detailed knowledge about the different parameters of cruciate ligaments, which will guide them in appropriate size of the allografting procedure in surgical reconstruction. The present research seeks to study the morphometric parameters of cruciate ligaments of the knee joint.
ACL injuries shows long term effects on knee joint such as degenerative joint disease, secondary osteoarthritis. So, reconstruction of ACL is essential in injured cases. For planning reconstruction surgery techniques it is essential to know the detailed anatomy & morphometric measurements of ACL. The Morphometric analysis of PCL has great value during surgical treatment of injured PCL, in fact it is observed that graft stretching or shortening along flexion when the tunnels are misplaced while reconstructing the PCL[10].
In this study we measured length of ACL by the point mark between postero-lateral surface of the Inter-condylar (IC) notch & anteriorly to the IC eminence. The length of PCL was measured by the point mark between lateral border of the medial femoral condyle & the posterior aspects of the medial & lateral tibial plateau. & width of ACL & PCL measured by their tibial femoral attachment as well as middle portion of antero-medial & posteromedial bundles separately. In this study we have measured length & width of ACL at 900 angles. Rajarshi D et al, Geetha Rani BG et al. & Yelicharla AK et al also opted the similar methodology in their respective study[11-12].
In conclusion our study demonstrated morphometric parameter of both ACL & PCL & its variation between right & left knees in the Indian population. This can help surgeons make critical decisions concerning graft size, preference for double bundle reconstruction & appropriate position of tunnels in the tibial & femoral counterparts in arthroscopic ACL & PCL reconstruction procedures.