Joints of the Lower Limb PDF

Here is the converted markdown format of the document # CHAPTER 32 Joints of the Lower Limb The joints of the lower limb include: 1. Hip joint 2. Knee joint 3. Tibiofibular joints 4. Ankle joint 5. Foot joints *The hip joint is already described in detail in Chapter 26. The remaining joints are d...

Here is the converted markdown format of the document # CHAPTER 32 Joints of the Lower Limb The joints of the lower limb include: 1. Hip joint 2. Knee joint 3. Tibiofibular joints 4. Ankle joint 5. Foot joints *The hip joint is already described in detail in Chapter 26. The remaining joints are described in this chapter* ## KNEE JOINT The knee joint is the largest and most complicated joint in the body. It is the major weight-bearing point in the body, It is prone to undergo degenerative changes with advanced age leading to osteoarthritis, hence it should be studied thoroughly. ### TYPE It is a synovial point of modified hinge variety. Is is not a typical hinge joint because it undergoes some degree of automatic (conjunct) rotation during flexion and extension of the knee. Actually, it is a compound Joint consisting of three articulations: right and left condylar joints between the condyles of the femur and tibia, and one saddle joint between the femur and patella (Figs 32.1 and 32.2). ### ARTICULAR SURFACES (Figs 32.1-32.3) The articular surfaces of the knee joints are: 1. Articular surfaces of medial and lateral condyles of the femur. 2. Trochlear surface of the femur. 3. Articular surface of the patella. 4. Articular surfaces of medial and lateral condyles of the tibia *Image shows the different parts of the knee joints, labels : Femur, Patello- femoral, Femur, Trochlear surface of femur, Patella Articular cartilage, Lateral femora tibial joint, Medial femora tibial. Head of fibula, Tibia -fibula* **Fig. 32.1** Three primitive joints included in the knee joint: A condylar type of medial and lateral femorotibial points; B, saddle type of patellofemoral joint. The articular surfaces of the knee joint are described in detail in the following text: 1. Articular surfaces of medial and lateral condyles of the femur occupy the anterior, inferior, and posterior surfaces of these condyles respectively. They are convex anteroposteriorly and from side to side. The medial condylar surface is longer anteroposteriorly and narrower or mediolaterally than that of lateral condyles. Anteriorly the anterior with each other through trochlear surface of the femur but posteriorly they are separated from each other by an intercondylar notch. 2. Trochlear surface of the femur is located on the anterior aspect of the lower end of the femur. It articulates with the posterior surface of the patella. It is pulley-shaped, consisting of medial and lateral sloping surfaces meeting with each other in a median vertical groove. The lateral sloping surface is longer than that of medial. *Image shows the inferior aspect of patella and lower and femur B, posterior aspect of the patella C, superior aspect of the tibia, labels Patellar articular surface of femur, Lateral condyle, Full flexion, Anterior cruciate ligament, Anterior horn of lateral meniscus, Lateral Condyle, Posterior horn of A, B, lateral meniscus C, Patella, corresponding facets in full knee flexion Medial condyle Flexion, slight Flexion, Extension Ligamentum patellae, anterior horn of medial meniscus Medial condyle, posterior horn of medial meniscus, posterior cruciate ligament* **Fig. 32.2** Articular surfaces of the knee joint: A, inferior aspect of the patella and lower end of the femur; B, posterior aspect of the patella; C, superior aspect of the tibia. 3. Articular surface of the patella is on the posterior aspect of patella and articulates with the trochlear surface of the femur. It has larger lateral area and a smaller medial area. Near the medial margin of patella, there is a narrow semilunar strip which comes in contact with a similar strip on the medial condyle of femur in full flexion. 4. Alticular surfaces of the medial and lateral condyles of tibia are on the upper surfaces of these condyles. They are separated from each other by a rough intercondylar area. * The articular surface on medial tibial condyle is oval and larger, It's anteroposterior diameter is more than the transverse diameter. * The articular surface on the lateral tibial condyle is circular. The articular surfaces on the upper surfaces of the medial and lateral condyles of the tibia are slightly concave centrally and flat at the periphery where they are covered by the corresponding menisci. ### STABILITY OF THE KNEE JOINT Structurally, the knee joint is relatively weak because of the incongruence of its articular surfaces. The tibial condyles are *Image shows Radiography of the knee joint AP view, B, lateral view C, sky view, labels, intercondylar, Patella-Femur femoral notch, Femoral Condyle, Tibia, Head of fibula, Femoral, Medial femoral condyle, Neck of fibula, Tibial tuberosity, Patella, Medial femoral condyle, C, Lateral Femoral condyle* **Fig. 32.3** Radiograph of the knee joint: A, AP view; B, lateral view; C, sky view. (Source: Fig 8.2, Page 220, Integrated anatomy, Heylings, David JA; Spence, Roy JA; Kelly, Barry E. Oxford: Churchill Livingstone, 2007. All rights reserved) Too small and shallow to hold the large complex femoral condyles. The femoropatellar articulation is also not quite stable because their shallow articular surfaces and due to an outward angulation between the wrong axes of the femur and tibia. ### Factors Maintaining the Stability of the Knee Joint The stability of the knee point is maintained by the following factors: 1. Strength and actions of the surrounding muscles and tendons. 2. Medial and lateral collateral ligaments maintain side-to-side stability. 3. Cruciate ligaments maintain the anteroposterior stability. 4. Iliotibial tract helps in stabilizing partly flexed knee. ## LIGAMENTS The important ligaments of the knee joints as follows (Fig 32.4): 1. Capsular ligament 2. Ligamentum patellae 3. Tibial and fibular collateral ligaments. 4. Anterior and posterior cruciate ligaments. 5. Medial and lateral menisci. *Image shows ligaments of the knee joint posterior aspects of the femur and tibia. The arrows indicate gaps in the capsule, labels, Femur, Capsular ligament, Lateral epicondyle, Gap for suprapatellar bursa, Addictor tubercle, Medial epicondyle Posterior cruciate ligament. iliotibial, ligament, patella, Tibia, B capsule, Femur Ligament Addictor tubercle, Capsule of femur, Anterior for tendon capsule Anterior cruciate ligament, Capsule ligament for tendon popliteus, Groove of, fibular facet, Tendon of Soleal Line. B* **Fig 32.4** Attachment of capsular ligament of the knee point: A, anterior aspects of the femur and tibia; B posterior aspects of the femur and tibla. The arrows indicate gaps in the capsule. Anteriorly it descends along the margins of the condyles to tibial tuberosity where it is deficient for the attachment the ligamentun patellae. Posteriorly it presents a gap behind the lateral condyle for the passage of the tendon of poplitues muscle. ### Synovial Membrane The synovial membrane (Fig 32.5) lines the inner aspect of the fibrous capsule and the portions of the bones enclosed within in but ceases the periphery of the articular cartilages medial and lateral menisci. In front above the patella, it is prolonged as suprapatellar bursa, and below the patella, it covers deep surface of the infrapatellar pad of fat, which separates it from the ligamentums patellae. The apex of suprapatellar bursa is attached to the articularis genu muscle. A median triangular fold of the synovial membrane called infrapatellar fold extends upward and backward forward from the patella of fat intercondylar fossa of the femur. The lateral margins of the infrapatellar Synovial fold are free from alarm folds which contain the fibrotty tissue. From the posterior aspect of the fibrous capsule, the synovial membrane projects forward in the intercondylar regions as cul-de-sac to envelope the sides of both cruciate ligaments in front of the interior cruciate ligament. *Image shows Knee Joint, labels, Anterior cruciate ligament, posterior ligament, capsule tibial collateral ligaments, meniscal, femeral, compartment tendon of semimembranosus, fibula A and tibia, Quadreceps femoris, Supra pateller bursa, patella, infrapatellar synovial, ligamentum patellae, lateral menisucus, medial meniscus, Tibia* **Fig 32.5** Knee point: A coronal Section. B sagittal Section, L- lateral meniscus, M-medial meniscus ### Ligamentum Patellae It is actually the tendon of insertion of the quadriceps femoris, which extends from the apex of the patella to the upper joint of the tibial tuberosity. Ligamentum patellae is about 7.5cm long and 2.5cm broad. It is attached above to the margins and rough posterior surface of the apex of patella and below it attached to the smooth upperpart of tibial tuberosity. It is related to the subcutaneous and deep infrapatellar bursa, and infrapatellar of fat. ### Tibal (Medial) Collateral Ligament (Fig 32.6a) It is a strong, long (about 10cm), thick is flat band or fibrous tissue. It consists of superficial and deep parts. Parts are attached about to the middle below the adductor tubercle. The superficial part of the ligament is long and attached below the upper part of the middle boarders adjoining posterior middle surface of the tibia. It covers inferior middle genecular serve vessels, anterior part of tendon of semimembranosus. The tendons of sartorius, gracilis, and semitendiosus across its lowerpart superficially. The deep part of the ligament is short blends in the cartlidge blend in the peripheral margins of tendons medial meniscus. is attaced below boarder the medial condyle tibia above tendon for the groove or semimembranosus ### Fibular (Lateral) Collateral Ligament (Fig. 32.6b) It is short (about 5cm long) chord light ligament. Above is attached to the part of the ligament just above the popiteal groove. Below is embraced by the tendon *Image shows the Attachments and relations of collateral ligaments of the knee Joint. The tibial lateral collateral ligaments, labels, Capsular ligament, Tendon of, popliteius Parts tibial Collateral ligament, of biceps, ligament femoral, tendon , superficial, semimembranosus Inferior middle genocular serve, the sartorius, gracilis semitendonosus* **Fig 32.6** Attachments and re lations of collater al ligaments of the knee point: A, fibular (lateral collateral and relations Biceps remoris attached to the head of fibula attached to head of ribula attached from of the apex. Its surface does not attached to the part of the fibrous capsule. It is separated from the capsules, its lower separated separated Morphologically, the medial collaterals morphological represents. the middle represents Degernerated insertion ischial hades, Degenerated longus strongers stabillization side ### Cruciate Ligaments These are two points with axis and union are direct bones maintain and are named The cruciate is intracasuportial *Image shows Anterior and posterior, note that the knee extension, posteior Knee extension, Labels Anterior cruciate ligament, posterior ligaments* **Fig 32.7** Anterior and posterior are taunt posterior is taut anterior for dislocation femur posterial dislaction lateral #### Medial Lateral Menisci (Semilunar Cartilages, Fig 32.8) These desc are central, the central lower the *ligament with transvese ligiment CO Posterier , fibula Tendon of Popliteus* **Fig 32.8** Medial and lateral points |Table 32.1 Differences | | | -------- | -------- | | Medial| Laterai| |C shaped | O shaped| |Atached to the medial | Poplitues | |More Prone | Less prone to damage| ### Funtions of the menisci These are as follows 1. The menens increase the better conguence femur. 2. The act to joint. 3. They absorb to during weight is important from *Image shows Obilque tibial ligament and Lateral Lateral side* ### Obilque tibial ligament The tibial blends from blend *Image shows Bursae around the knee joint and Tibia* **Figure 32.9** Bursae of the knee front of the knee ### Arterial Supply 1. Knee it can make a big and take it original position *Note* The is to take knee to original and take knee to original ## Relations of the Knee They are as follows *Image Show Knee Joint Section Section Labels for joint* ### Functions of the menisci These are as flows; The increase concave tibial and Clinical Correialtion *Image Shows leg in action with torn legiaments* Fig 32.11 Points for the of Joints THE points These are for joint and points . ## THE JOINTS These section the and the sections for for ## INFERIOR POINT This of all is due *Image Shows the fibula and how joints look on a AP and side of views* *The* body, the of three of the to show how look ## TIBIA LOOK ### Stability of the Ankle