Middle Patellar Ligaments Research Articles

Morphological and Morphometric Study on Stifle Joint of Dromedary Camel (Camelus dromedarius)

Morphological and morphometric study was conducted on 10 freshly collected stifle joints from cadaver of adult dromedary camels (Camelus dromedarius) of local breed. In morphological study all the important anatomical structures were identified. The medial patellar ligament could not be evidenced but a medial femoropatellar ligament running between the medial epicondyle of femur and patella was found. Another strap like ligament like structure originating from medial femoral fascia and inserted on the tibial tuberosity was evidenced and it was supposed to support the patella in its normal position. The medial collateral ligament was present but its lateral counterpart could not be evidenced. The medial intercondylar tubercle of tibia was found to be somewhat elevated and larger than the lateral one. Morphometric data (length, width and thickness) of the important ligaments and anatomical structures (articular surfaces) were measured. The orientation of the medial femoro patellar ligament was at an angle of 113.8° ± 1.93° with the middle patellar ligament. There was an angle of 82.7° ± 1.77° between the meniscofemoral ligament and the ligament connecting the menisci caudally. Descriptive statistics were given as Mean ± SD (standard deviation) along with coefficient of variation to show variability of a particular dimension.

Intermittent upward fixation of the patella in 12 cows: A retrospective study of treatment and long-term prognosis

This retrospective study investigated possible risk factors for intermittent upward fixation of the patella and the outcome of medial patellar desmotomy in 12 cows. All but one young cow had distinctive clinical signs, which usually started in the periparturient period. Medial patellar desmotomy led to normalisation of the stride in 10 cows but did not improve the condition of the young cow. Another cow developed instability and signs of lateral patellar luxation in the affected stifle and was euthanized. The 10 cows that were operated successfully remained in the long term free of symptoms. Medial patellar desmotomy is a suitable treatment for upward patellar fixation in cattle but should be reserved for cows with typical clinical signs. The medial patellar ligament should be cut 4 to 6 cm proximal to its insertion on the tibia to minimise the risk of injury to the middle patellar ligament.

Advanced imaging studies on normal stifle joint of camel (Camelus dromedarius)

Computed radiography and computed tomographic scanning of normal stifle joint of camel obtained from cadaver were studied and compared. The radiography revealed only the bony structures involved in the joint whereas CT scan revealed both bony and soft tissues. Lateral, cranio-caudal and caudo-cranial radiographs were taken which revealed all bones and articular surfaces of stifle joint. CT scan studies were done on 3-D, transverse and sagittal sections. Medial patellar ligament was not evidenced, however, the medial femoro-patellar ligament was distinguishable. Other important anatomical structures evident were cranial and caudal cruciate ligament, medial collateral ligament, lateral patellar retinaculum, middle patellar ligament, attachments of lateral and medial menisci and most of the associated muscles around stifle joint. CT scan also revealed the bony structures of the joint i.e. femoral trochlea, femoral condyles, tibial condyles, intercondylar tubercles, patella, tibial tuberosity etc.

Clinical aspects of the equine stifle joints Part 2: The femorotibial joint

The femoropatellar joint is the articulation between the femoral trochlea and the patella which acts as the surface over which the patella glides. The medial trochlear ridge is considerably larger than the lateral trochlear ridge.The patella has three distal ligaments: the medial patellar ligament originates via a wide attachment to both the medial aspect and base of the patella via a broad region of fibrocartilaginous tissue and attaches distally medial to the groove on the cranial aspect of the tibial tuberosity; the middle patellar ligament courses from the cranial aspect of the patella to an attachment on the tibial tuberosity; and the lateral patellar ligament which runs from the lateral part of the patella to the lateral aspect of the tibial crest.The femoropatellar joint is a voluminous joint that readily produces an effusion in the presence of pathology. Such effusions are usually readily palpable as fluid swellings discernible between the patellar ligaments. In some disease situations the effusion from the joint can be massive, completely obscuring the patellar ligaments.There is also a large proximal suprapatellar pouch, although

Normal ultrasonographic anatomy and injury of the patellar ligaments in the horse.

The purposes of this study were to investigate the ultrasonographic appearance of the patellar ligaments in clinically normal horses and to describe the clincical features, diagnosis and outcome of patellar ligament injury. The medial, middle and lateral patellar ligaments of 5 Thoroughbred and 5 Warmblood horses, free from lameness and in full work, were examined ultrasonographically. The ligaments were all of uniform echogenicity and each ligament was fairly consistent in its shape. The size of the ligaments of the Warmblood horses tended to be bigger than the lighter bodyweight Thoroughbred horses. The bone surfaces were smooth at the ligament insertions on the patella and tibia. Nine horses, including 7 showjumpers, were identified with a unilateral hindlimb lameness associated with ultrasonographic evidence of damage to one or more patellar ligaments. Four horses had primary desmitis of the middle patellar ligament, one of which had concurrent intermittent upward fixation of the patella and a second had abnormal movement of the patella. Two additional horses had desmitis of the middle patellar ligament associated with previous medial patellar desmotomy. Two horses had desmitis of both the middle and lateral patellar ligaments, and one horse had desmitis of the lateral patellar ligament alone. None of the 9 horses were able to return consistently to their former level of competition. Careful clinical evaluation and ultrasonographic examination of the patellar ligaments should be considered in horses with hindlimb lameness of otherwise undetermined cause.

Production of patellar lesions by medial patellar desmotomy in normal horses.

Medial patellar desmotomy was performed on one (treated) hindlimb, and a sham operation on the other (control) hindlimb, of 12 normal horses. The horses were examined for lameness before medial patellar desmotomy and at months 1, 2, and 3. The femoropatellar joints were examined radiographically and arthroscopically at month 3. All horses were lame on the treated limb at months 1, 2, or 3. Radiographic changes, including fragment formation at the distal aspect of the patella and bone production at the attachment of the middle patellar ligament on the patella, were present in 11 horses at month 3. Articular cartilage fibrillation or detachment was seen arthroscopically on the patellas of all treated limbs. In six horses, loosely attached fragments of bone and cartilage were removed arthroscopically from the distal aspect of the patella of the treated limb. The control limbs were clinically, radiographically, and arthroscopically normal throughout the study. Medial patellar desmotomy results in pathologic changes in the articular cartilage of the patella and adjacent soft tissues. Use of this surgical procedure should be reserved for persistent and confirmed cases of upward fixation of the patella.

The effects of injection of an iodine counterirritant into the patellar ligaments of ponies: Application to stifle lameness

Patellar fixation is a common cause of lameness in horses and has been successfully treated by injection of the patellar ligaments with counterirritants. To investigate the effects of this treatment, the medial and middle patellar ligaments of 10 ponies were injected with an oil-based iodine counterirritant solution and then examined morphologically. Vacuoles of counterirritant were present in the paratenon and endotenon of the ligaments and caused severe necrosis and inflammation. At 1 day after injection, there was a marked neutrophilic infiltration which progressed to a lymphocytic infiltrate by 3 days. By 7 days, fibroplasia was present and became more organized with time. Disrupted collagen fibers and numerous, large, pale fibroblasts were present in the fasciculi, but neutrophilic infiltration was absent. The fibrous response in the fasciculi was similar to that present in the paratenon and endotenon. At 28 days, the drug was still present as lipid vacuoles in the paratenon and endotenon, and the damaged fasciculi had not regained their normal appearance. The clinical effect of this treatment was attributed to the change in size and shape of the patellar ligaments resulting from the inflammatory response.

The effects of injection of an iodine counterirritant into the patellar ligaments of ponies: Application to stifle lameness

Patellar fixation is a common cause of lameness in horses and has been successfully treated by infection of the patellar ligaments with counterirritants. To investigate the effects of this treatment, the medial and middle patellar ligaments of 10 ponies were injected with an oil-based iodine counterirritant solution and then examined morphologically. Vacuoles of counterirritant were present in the paratenon and endotenon of the ligaments and caused severe necrosis and inflammation. At 1 day after injection, there was a marked neutrophilic infiltration which progressed to a lymphocytic infiltrate by 3 days. By 7 days, fibroplasia was present and became more organized with time. Disrupted collagen fibers and numerous, large, pale fibroblasts were present in the fasciculi, but neutrophilic infiltration was absent. The fibrous response in the fasciculi was similar to that present in the paratenon and endotenon. At 28 days, the drug was still present as lipid vacuoles in the paratenon and endotenon, and the damaged fasciculi had not regained their normal appearance. The clinical effect of this treatment was attributed to the change in size and shape of the patellar ligaments resulting from the inflammatory response. Approximately 90–95% of stifle lamenesses have been attributed to problems involving the patellar ligaments, 2 which are essentially continuations of the tendons of insertion of the quadriceps femoris and biceps femoris muscles. 3 Upward fixation of the patella has long been recognized in horses in which the stifle joint becomes locked in extension, thus preventing flexion and normal advancement of the limb. 6 If forced to advance the limb, the horse may drag its toe on the ground. A more common and subtle form of this condition also occurs. A momentary fixation of the patella may occur which results in a painful, inflamed joint, but obvious locking of the stifle is not seen. 8 This problem is common in performance horses. Diagnosis of the mild form of patellar fixation can be made by standing the horse squarely with the affected stifle in extension and the patella in its most proximal position. According to Habel, 4 this is the resting position of the patella as described by Preuss and Henschel. 10 With the palm of the hand placed on the patella (left hand for left patella, right hand for right patella), the examiner forces it caudally and slightly proximolaterally (Figure 1). While pressure is maintained on the patella in this manner, the person handling the horse is instructed to move the horse ahead one step. Normally, the medial parapatellar fibrocartilage, which is considered part of the medial patellar ligament, 3 will readily disengage from the medial femoral trochlea, 4 in our clinical experience, this is not the case in conditioned horses. Medial patellar desmotomy is commonly performed on horses with patellar fixation. 6 8 1 9 This procedure has the disadvantage of interrupting the horse's training program. An infrequent but disastrous sequel is rupture of the middle patellar ligament and the resulting inability to extend the stifle joint. As an alternative, application of external blisters to the stifle was recommended many years ago. 6 9 Injection of counterirritants into the medial and middle patellar ligaments has been described. 8 This latter treatment, in conjunction with a continued exercise program, has been used successfully by one of the authors (MPB) to treat clinical cases of patellar fixation. The purpose of this study was to evaluate the histological effects of injection of an iodine counterirritant solution into the patellar ligaments of ponies and relate these changes to the apparent clinical effectiveness of this treatment in horses with patellar fixation.

Surgical stabilisation of the stifle in cranial cruciate ligament injury in cattle.

Surgical stabilisation of cranial cruciate ligament injury was performed on 23 stifles in 22 dairy cattle ranging in age from 11 months to 14 years. Duration of time from injury until surgery varied from two days to three years. A row of Lembert sutures was placed in both the lateral and medial retinacular tissues. In addition, an imbrication suture was placed from the lateral femorotibial ligament to the lateral or middle patellar ligament in five cattle. External support was used in 15 cattle in the form of a modified Robert Jones/Thomas-Schroeder splint. Thirteen cattle improved markedly, four recovered completely and three improved moderately. Surgery was unsuccessful on seven cases. When surgery was unsuccessful, moderate to severe lesions of degenerative joint disease were usually present.

A Study on the Nerve Supply of the Knee Joint In Cattle

The nerve supply of the knee joint in cattle was studied by dissections on sucking-calves and by nerve staining of section series of foetal joints. Four distinct nerves to the joint were observed. They were given off by the N. saphenus to the medial and distal anterior regions of the joint, by a branch from the N. femoralis within the M. rectus femoris, to the middle patellar ligament, by the N. tibialis to the posterior capsule, and by the N. peronaeus to the region of the lateral collateral ligament. The microscopical studies revealed minor additional bundles to the posterior capsular r egion from the N. saphenus, the N. tibialis, and the N. peronaeus, as well as some bundles from the N. femoralis to the M. vastus intermedius, possibly innervating the proximal part of the femoro-patellar joint capsule. Many of the largest fibres ramified on or near the surfaces of the collateral ligaments and the middle patellar ligament.