The synovial membrane is attached to the articular margins of the joint and lines the capsule and annular ligament. The capsule attaches to the articular margin except at the coronoid, radial, and olecranon fossae, where it attaches to the rim of the fossae (Fig. 1.11). The joint capsule does not attach to the radius; it is confluent with the annular ligament that attaches to the anterior and posterior margins of the sigmoid notch and encircles the radius. Haversian fat pads are located in each of these fossae between the capsule and synovial membrane. Distention of the joint by hemarthrosis displaces these fat pads out of their respective fossae and produces the characteristic "fat pad sign" seen on lateral radiographs. The anterior capsule is normally a thin transparent structure through which the surgeon can visualize the prominences of the articular condyles. The anterior capsule becomes taut in extension and is an important stabilizer of the extended elbow. The maximum joint capacity is 25 to 30 mL at approximately 80° of flexion.20
The ligamentous complexes that stabilize the joint are thickenings of the capsule on its medial and lateral as-pects.The medial collateral ligament complex consists of three components: the anterior and posterior bundles and the transverse ligament (Fig. 1.12).The anterior bundle is structurally and biomechanically the significant component of the medial collateral ligament complex and has three functional bands. The first band arises from the anterior surface of the medial epicondyle and is taut in extreme joint positions. The second band arises below the tip of the epicondyle and is taut in intermediate joint po-
Fat pad within the
Fat pad within the olecranon fossa
Fat pad within the
FIGURE 1.11. Elbow capsule and synovial reflections. (A) Anterior view. (B) Posterior view. (C) Lateral view of capsule showing its relationship to annular ligament. (D) Sagittal section of the elbow showing intracapsular extrasynovial Haversian fat pads.
sitions. The third band, which arises from the inferior edge of the epicondyle, is taut throughout the full range of joint motion (isometric).21 The anterior bundle attaches to the sublime tubercle on the medial aspect of the coro-noid process. Its mean length and width are 27 mm and 4 to 5 mm, respectively.
The posterior bundle (Bardinet's ligament) of the medial collateral ligament complex is fan shaped and attaches inferior and posterior to the axis of rotation on the medial epicondyle.21 It attaches to the middle of the medial margin of the trochlear notch and is taut during flexion. Its mean length is 24 mm, and its mean width is 5 to 6 mm at the middle portion. This ligament is important because it provides stability to the elbow against pronation. The transverse ligament of Cooper (olecra-non coronoid ligament) is not always well defined and does not contribute to joint stability because it is limited only to the ulna.
The medial collateral ligament complex lies under the prominence of the medial epicondyle. Therefore, when performing a medial epicondylectomy, the surgeon can excise the medial fifth of the width of the epicondyle (1 to 4 mm) without violating the medial collateral liga-ment.22 O'Driscoll et al. recommend that the osteotomy should be in a plane between the sagittal and coronal planes, with removal of a greater amount of the posterior portion of the epicondyle.22
The lateral ligament complex consists of four components: the radial collateral ligament, the annular ligament, the lateral ulnar collateral ligament, and the accessory lateral collateral ligament (Fig. 1.13). The radial collateral ligament attaches to the lateral epicondyle and merges indistinguishably with the annular ligament. Its mean length and width are 20 mm and 8 mm, respectively. The annular ligament attaches to the anterior and posterior margins of the radial notch of the proximal ulna, encircling the radius but not attaching to it. The most dis
tal aspect of the annular ligament has a smaller diameter that encircles the neck to provide greater stability.
The lateral ulnar collateral ligament attaches prox-imally to the lateral epicondyle and distally to the tubercle of the supinator crest of the ulna. It is the primary lateral stabilizer of the ulnohumeral joint, and its deficiency is the "essential lesion" that produces posterolateral rotatory instability.23,24 The humeral attachment is at the isometric point on the lateral side of the elbow. In some patients, this ligament cannot be distinguished from the capsule.25 The capsule posterior to this named ligament is also important because it provides resistance against supination.
The accessory lateral collateral ligament blends proximally with the fibers of the annular ligament and distally attaches to the tubercle of the supinator crest. The function of the accessory ligament is to stabilize the annular ligament during varus stress.
The quadrate ligament of Denuce is a thin fibrous layer between the inferior margin of the annular ligament and the ulna. It is a stabilizer of the proximal radioulnar joint during full supination.
The oblique ligament is a small and inconstant ligament formed by the fascia overlying the deep head of the supinator between the ulna and radius just below the radial tuberosity. It has no known functional importance, but some authors believe this ligament is a cause of rotatory contractures of the forearm.26
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Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.