Review article http://dx.doi.org/10.4322/jms.053513 Reviewing morphology of Quadriceps femoris muscle CHAVAN, S. K.* and WABALE, R. N. Department of Anatomy, Rural Medical College, Pravara Institute of Medical Sciences, At.post: Loni- 413736, Tal.: Rahata, Ahmednagar, India. *E-mail: [email protected] Abstract Purpose: Quadriceps is composite muscle of four portions rectus femoris, vastus intermedius, vastus medialis and vatus lateralis. It is inserted into patella through common tendon with three layered arrangement rectus femoris superficially, vastus lateralis and vatus medialis in the intermediate layer and vatus intermedius deep to it. Most literatures do not take into account its complex and variable morphology while describing the extensor mechanism of knee, and wide functional role it plays in stability of knee joint. It has been widely studied clinically, mainly individually in foreign context, but little attempt has been made to look into morphology of quadriceps group. The diverse functional aspect of quadriceps group, and the gap in the literature on morphological aspect particularly in our region what prompted us to review detail morphology of this group. Method: Study consisted dissection of 40 lower limbs (20 rights and 20 left) from 20 embalmed cadavers from Department of Anatomy Rural Medical College, PIMS Loni, Ahmednagar (M) India. Results: Rectus femoris was a separate entity in all the cases. Vastus medialis as well as vastus lateralis found to have two parts, as oblique and longus. Quadriceps group had variability in fusion between members of the group. The extent of fusion also varied greatly. The laminar arrangement of Quadriceps group found as bilaminar or trilaminar. The insertion level of vastus medialis and vastus lateralis on patella varied greatly. Vastus lateralis found to extent to whole extent of lateral border of patella. The extension of fibrous band like structure from lower horizontal fibers of vastus medialis to adductor tubercle also noticed in one case. Conclusion: There is wide variability in the quadriceps group of muscles that we came across, then believed. This variability in the quadriceps group might affect the stability of the knee joint but needs, to prove clinically. The finding may also help in the understanding the factors associated with anterior knee pain and its management. Keywords: Quadriceps, vastus medialis oblique, vastus medialis longus, vastus lateralis longus, laminar arrangement, extent of insertion. 1 Introduction Quadriceps muscle is composed of four parts namely rectus prevents posterior displacement of tibia. The strongest of the femoris, vastus medialis, vastus lateralis and vastus intermedius. group represented by VL apply lateral force to patella. As a The composite muscle inserted through common tendon on whole VM is extensor, VMO is medial stabilizer of patella. patella and through it to the smooth part of tibial tuberosity. RF of the quadriceps group works as knee extensor only when The common tendon has three layered arrangement, rectus hip joint is in extension, by lengthening the rectus femoris femoris (RF) superficially, vastus lateralis (VL) and vastus (HAMILL and KNUTZEN, 2009).In activities of daily living medialis (VM) in the intermediate layer and vastus intermedius contraction of QF required primarily to raise and lower the (VI) deep to it (WALIGORA, JOHANSON and HIRSCH, weight of body while upright. Such activities include getting 2009). Vastus Medialis has been described as having two discrete in and out of chair or climbing stairs (OATIS, 2009). parts the vastus medialis oblique (VMO) and vastus medialis The line of traction of these muscles is along the axis of longus (VML) (LIEB and PERRY, 1968). There are also two femur but is not in line with tibia. It results in the tendency to parts of VL, the vastus lateralis oblique (VLO) and vastus displace the patella in lateral direction (PEELER, COOPER, lateralis longus (VLL) described by (SCHARF, WEINSTABL PORTER et al., 2005). This is prevented by three morphological and FIRBAS, 1986) for the first time. All muscles in the group formations. The expanded anterior surface on the lateral cause extension at the knee except RF that is also a flexor at condyle of the femur behaves like a buttress preventing lateral the hip joint. Quadriceps femoris (QF) muscle group, the displacement of patella. Secondly, the pull of medial extensor producer of extension at knee is three times stronger than its retinacula also said to resist lateral pull and the third factor antagonistic group, the hamstrings because it is involved in is the stabilization imparted to patella by horizontal fibers of negatively accelerating the leg and continuously acting against VMO (OATIS, 2009). In spite of that, the Patellar instability gravity. By its extension to tibial tuberosity it contribute to is one of the common problems that orthopaedician come stability of patella. As a muscle group, they also pull the across. Patellar instability, including sub-luxation, relates menisci anteriorly in extension via meniscopatellar ligament. to the imbalance of the soft tissues. Atrophy, (WILLAN, When they contract, they also reduce the strain in medial MAHON and GOLLAND, 1990) weakness, (FARAHMAND, collateral ligament. Working with posterior cruciate ligament SEJIAVONGSE and AMIS, 1998) a more proximal attachment 112 J. Morphol. Sci. , 2016, vol. 33, no. 2, p. 112-117 Quadriceps Femoris Morphology of the VMO (FULKERSON, 2004) and overdevelopment hyperextension at hip and leg is fixed at knee (HAMILL and of the VL (HUGHSTON, WALSH and PUDDU, 1984) KNUTZEN, 2009). have been suggested as causes of patella-femoral dysfunction. In climbing stairs after the limblift initiations by iliopsoas, Considering the two parts of VL as VLO and VLL, (HALLISAY, RF becomes active to flex the thigh and eccentrically slow DOHERTY, BENNETT et al., 1987) stressed the importance the knee flexion. In pull-up phase in which limb is placed on of surgically releasing this muscle to reduce the lateral tension the upper step, extension in the knee joint is brought about on the patella. by quadriceps of the same side to bring body to that step Recently the QF complex is been the subject of renewed (HAMILL and KNUTZEN, 2009). interest with regard to histological composition, the anterior There is considerable muscle activity in multiple muscles lateral part of the muscle frequently chosen for electromyography during running. At knee joint, both hamstring and quadriceps and skeletal muscle biopsy (SWASH and SCHWARTZ, 1997). are active during stance phase. The heel strike phase in running Most biopsy samples from VL show considerable variation in is followed by activation of QF, which initially act eccentrically muscle fiber size and fiber type proportions between individuals to slow the negative verticals of body velocity, this action and even between samples from the same individual (MAHON, lasts till mid support phase. The QF then act concentrically TOMAN, WILLAN et al., 1984). It is interesting to note that to produce positive vertical velocity of body, both hamstring Edgerton, Smith, and Simpson (1975) showed quantitative and QF is active to generate extension at hip. In propelling histological differences between samples from VL and the phase of support, quadriceps is eccentrically active as the heel underlying VI (WILLAN, MAHON and GOLLAND, 1990). lifts off and then becomes concentrically active up through Amongst the various group of muscles, the Quadriceps group toe-off phase. During initial portion of swing phase, quadriceps considered to have least variations (STANDING, COLLINS, is active eccentrically to slow rapid knee flexion (HAMILL CROSSMAN et al., 2008). This group is crucial for stability of and KNUTZEN, 2009). knee joint in all possible knee joint positions, since it is active In walking, after the arrest of movement at the hip joint in both extension as well as controlled flexion. We thought at heel strike, the quadriceps begins to contract to control it essential to explore detailed morphology of this muscle weight imposed on knee joint by the body and by the reaction considering its massive presence on anterior aspect of thigh. force coming up from ground, the knee moves into flexion As well as its varied functional and clinical aspects and paucity eccentrically controlled by the QF. Co-contraction of QF and of literature on detailed morphology of quadriceps group in hamstring continues until foot is flat on ground. The activity Indian populations, hence this study was undertaken. of QF diminishes at 30% of stance. During late swing phase, quadriceps becomes active which slows knee flexion after toe-off, 2 Materials and Method and initiate knee extension prior to heel strike (HAMILL and KNUTZEN, 2009). The study carried out in Department of Anatomy, Rural In cycling, the QF is very active from 0 to 90°. RF is active Medical College, Pravara institute of Medical Sciences, Loni, through arch of 200 to 130° of next cycle. VM is active from Ahmednagar (M) India. The study material consisted lower 300 to 135° and VL is active from 315 to 130° of next cycle. limbs of 20 human unclaimed cadavers in whom the cause From 270 to 360° the RF is actually involved as the leg brought of death could not be ascertained. The cadavers were fixed up into top position (HAMILL and KNUTZEN, 2009). in embalming fluid. Eighteen were male cadavers and two In our study in all the specimen four parts of quadriceps were female cadavers with an age in the range of 60 years group, were recognized easily. RF was a separate entity in and above. Total lower limbs dissected were 40; 20 of right all of the 40 limbs. None of the specimen showed fusion and 20 of left side. The limbs that were in straight position (HAMILTON, 1976) of RF with VM and VL. The tendon and devoid of any obvious pathology were included in the of RF receives VM and VL on either side 5 cm above the study.