it deals with the management of the ruptured cruciate ligaments in canines , i have gathered the information right from the predisposing factors , mechanism of injury , various diagnostic tests , and at last the treatment with old as well as latest techniques , all the pics that i have collected are from net , and few from books by pete muir and nunamaker ,
The cruciate ligaments of the stifle joint are the cranial cruciate ligament (CrCL) and the caudal cruciate ligament (CaCL). These ligaments are two strong, rounded bands . The CrCL is lateral and the CaCL is medial. They cross each other like the limbs of an X. The CrCL and CaCL remain distinct throughout and each has its own partial synovial sheath. Relative to the femur, the CrCL keeps the tibia from slipping forward and the CaCL keeps the tibia from slipping backward.
. 1 This is probably due to the fact that, with the exception of caudal displacement of the tibia, the caudal cruciate ligament is protected from extremes of motion by other joint structures.2 sometimes only on arthrotomy it is diagnosed that there is a ruptured caudal ligament , 3Experimentally, transection of the CaCL does not cause an obvious lameness and only leads to mild internal rotation of the tibia relative to the femur4Rupture of the CaCL often involves avulsion fracture of an attachment site and affected dogs usually have a history of trauma and may haveother complicating injuries
. In this position the cruciate ligaments begin to twist on each other and on themselves to limit the normal internal rotation of the tibia on the femur. With excessive internal rotation of the tibia, the cranial cruciate ligament becomes wound very tightly and is subject to trauma from the lateral femoral condyle as it rotates against it. This may cause the cranial cruciate ligament to rupture in its midportion or, in the case of younger animals, to avulse a portion of its bony attachment .Another mechanism of injury to the cranial cruciate ligament is hyperextension. The cranial cruciate ligament is the primary check against hyperextension of the stifle. Therefore, as the stifle is hyperextended, the cranial cruciate ligament is the first structure to be subject to injury
While acute cruciate ligament rupture due to trauma does occur, it is thought that the majority of cruciate lesions are a result of chronic degenerative changes within the ligaments themselves. Patellar luxation is a common problem that contributes to excessive stress on the cranial cruciate ligament owing to the fact that the stifle lacks the proper support of the quadriceps muscles and patellar ligament. In obese animals these stresses are increased and the possibility of degenerative joint changes is greater. As joint changes develop, the cruciate ligaments undergo alteration in their microstructure. Collagen fibrin become hyalinized, and the tensile strength of the ligament is reduced, making the ligament more susceptible to damage from minimal trauma. These changes also have been associated with the aging process and may explain the fact that the majority of cruciate injuries are seen in dogs over 4 years of age
In this maneuver the examiner grasps the metatarsus with one hand and places the palm of the hand over the cranial aspect of the distal femur and patella, extending the forefinger down over the tibial tuberosity. By flexing the hock, the reciprocal tightening effect of the gastrocnemius muscle acts to compress the tibia and the femur. If the cranial cruciate ligament is not intact, the tibial tuberosity will be felt to slide cranially. Tibial compression stress radiography is a valuableasset in the diagnosis of canine stifl e instabilitybecause of CrCL rupture. It is a useful techniqueto prove (or disprove) a tentative diagnosis ofCrCL damage, especially when there is a lack ofcranial drawer sign on clinical examination. Nofalse positive results were obtained. Tibial compressionstress radiography is able to detectcomplete or partial tears of the CrCL. It is aneasy and reliable technique that does not requireexpensive equipment or a high level of technicalproficiency.
Arthroscopic - assisted surgical techniques reduce postoperative pain and shorten the length of hospital stay and the time required for return to functionArthroscopic management of CrCL rupture reduces short - term postoperative morbidity compared to traditional arthrotomy technique A magnified view of anatomic structures of the stifle allows more accurate diagnosis and precise treatment of pathological conditionsArthroscopy of the stifle is commonly used to evaluate and treat CrCL tears, meniscal tears, osteochondrosis, osteochondral fragments, intraarticular foreign bodies, and septic arthritis.
A radiograph shows the spatial relationship between the bones at the joint level.On a neutral view of a normal canine stifle in 90 ° of flexion, the perpendicular on the femoral axis that runs just cranial to the fabellae, will be almost tangential to the caudal projection of the lateral tibial condyleThis particular sign is called “ Cazieux - positive, ” and always indicates a ruptured CrCL
It is the golden standard for diagnosing the cruciate ligament rupture,Traditional arthrotomy can be performed by a medial or lateral Para patellar approach depending on the surgeon ’ s preferenceSome surgeons prefer a medial parapatellar approach because they claim to have an improved view and better access to the medial meniscusA lateral arthrotomy may be best if a lateral extracapsular prosthetic CrCL is to be placed due to the need to have exposure to the caudolateral aspect of the joint
MRI recognition of joint lesions is based on alterations of signal intensity (SI) and morphologic changes.The combination of the joint capsule and synovial membrane is seen as a low SI structure on MR images.
Basically, the surgical procedures for cruciate ligament repair can be divided into the intraarticular and the extra-articular techniques. The intra-articular techniques use either an autogenous or a synthetic graft to actually replace the cruciate ligament) while the extra-articular techniques stabilize the joint by altering (tightening) extra-articular structures.(Before the individual techniques for cruciate ligament repair are discussed, it should be noted that in all cases of cruciate ligament repair, the joint should be opened by lateral or medial arthrotomy and inspected thoroughly for additional pathology. The remnants of the ruptured ligament should be removed and the joint irrigated thoroughly with lactated Ringer's or saline solution. If the joint has been unstable for a while, marginal osteophytes will be present along the margin of the femoral trochlea.(28) These osteophytes may be removed by sharp dissection with a scalpel blade if they appear too proliferative,It should be noted that in all cases of cruciate ligament repair, the joint should be opened by lateral or medial arthrotomy and inspected thoroughly for additional pathology. The remnants of the ruptured ligament should be removed and the joint irrigated thoroughly with lactated Ringer's or saline solution. If the joint has been unstable for a while, marginal osteophytes will be present along the margin of the femoral trochlea. These osteophytes may be removed by sharp dissection with a scalpel blade if they appear too proliferative