Medial Patellar Ligament Research Articles

Clinical presentation and surgical repair of traumatic lateral patellar luxation associated with a complete tear of the vastus medialis muscle in a neonatal Cob foal

SummaryPatellar luxation associated with traumatic injury is rare in the horse, and surgical correction has not been adequately described. This case report describes the clinical findings associated with traumatic lateral patellar luxation in a 2‐day‐old cob colt, and the technique used for successful surgical repair. A combination of computed tomography (CT), radiography and ultrasound was used to diagnose lateral luxation of the patella due to a complete tear of the vastus medialis muscle. All patellar ligaments were intact and no congenital abnormalities associated with the patellar luxation were present. Surgical correction of the patellar luxation was achieved using a lateral release of the patella performed by transection of the lateral femoropatellar ligament along with overlying fascia, and stabilisation of the patella by medial imbrication of the medial patellar ligament and parapatellar fascia to the distal tendon of the sartorius muscle. Radiographs at 18 weeks of age showed the patella in a normal position in a well‐developed trochlear groove. At 1 year of age the foal was walking and trotting sound, with normal range of motion of the affected stifle.

Quantitative and Qualitative Analysis of the Medial Patellar Ligaments: An Anatomic and Radiographic Study

Background: The qualitative and quantitative anatomy of the medial patellar stabilizers has been reported; however, a quantitative analysis of the anatomic and radiographic attachments of all 4 ligaments relative to anatomic and osseous landmarks, as well as to one another, has yet to be performed. Purpose: To perform a qualitative and quantitative anatomic and radiographic evaluation of the medial patellofemoral ligament (MPFL), medial patellotibial ligament (MPTL), medial patellomeniscal ligament (MPML), and medial quadriceps tendon femoral ligament (MQTFL) attachment sites, with attention to their relationship to pertinent osseous and soft tissue landmarks. Study Design: Descriptive laboratory study. Methods: Ten nonpaired fresh-frozen human cadaveric knees were dissected, and the MPFL, MPTL, MPML, and MQTFL were identified. A coordinate measuring device quantified the attachment areas of each structure and its relationship to pertinent bony landmarks. Radiographic analysis was performed through ligament attachment sites and relevant anatomic structures to assess their locations relative to pertinent bony landmarks. Results: Four separate medial patellar ligaments were identified in all specimens. The center of the MPFL attachments was 14.3 mm proximal and 2.1 mm posterior to the medial epicondyle and 8.3 mm distal and 2.7 mm anterior to the adductor tubercle on the femur and 8.9 mm distal and 19.9 mm medial to the superior pole on the patella. The MQTFL had a mean insertion length of 29.3 mm on the medial aspect of the distal quadriceps tendon. The MPTL and MPML shared a common patellar insertion and were 9.1 mm proximal and 15.4 mm medial to the inferior pole. The MPTL attachment inserted on a newly identified bony ridge, which was located 5.0 mm distal to the joint line. The orientation angles of the MPTL and MPML with respect to the patellar tendon were 8.3° and 22.7°, respectively. Conclusion: The most important findings of this study were the correlative anatomy of 4 distinct medial patellar ligaments (MPFL, MPTL, MPML, MQTFL), as well as the identification of a bony ridge on the medial proximal tibia that consistently served as the attachment site for the MPTL. The quantitative and radiographic measurements, while comparable with current literature, detailed the meniscal insertion of the MPML and defined a patellar insertion of the MPTL and the MPML as a single attachment. The data allow for reproducible landmarks to be established from previously known bony and soft tissue structures. Clinical Relevance: The findings of this study provide the anatomic foundation needed for an improved understanding of the role of medial-sided patellar restraints. This will help to further refine injury patterns and/or soft tissue deficiencies that result in lateral patellar instability, which can then be addressed with an anatomic-based reconstruction or repair technique and potentially lead to improved outcomes.

Canine cranial cruciate ligament deficient stifle biomechanics associated with extra-articular stabilization predicted using a computer model.

To evaluate lateral fabellotibial suture (LFTS) and TightRope CCL (TR) extra-articular stabilization biomechanics in the cranial cruciate ligament (CrCL)-deficient canine stifle joint during the stance phase of gait. Computer simulations. Healthy 33-kg Golden Retriever. LFTS and TR were implemented in a previously developed 3-D quasi-static rigid body CrCL-deficient canine pelvic limb computer model simulating the stance phase of gait. Ligament loads, relative tibial translation, and relative tibial rotation were determined and compared across the CrCL-intact, CrCL-deficient, and extra-articular stabilized stifle joints. Compared to the CrCL-intact stifle, peak caudal cruciate and lateral collateral ligament (LCL) loads were increased in the LFTS-managed stifle, peak caudal cruciate and LCL loads were decreased in the TR-managed stifle, and peak medial collateral and patellar ligament (PL) loads were similar for both techniques. Compared to the CrCL-deficient stifle, peak caudal cruciate, lateral collateral, and medial collateral ligament loads decreased, and peak PL load was similar in the LFTS- and TR-managed stifle joints. Peak relative tibial translation decreased, and peak relative tibial rotation changed from internal rotation to external rotation in the LFTS- and TR-managed stifle joints compared to the CrCL-deficient stifle. Our computer model predicted controlled tibial translation, decreased cruciate and collateral ligament loads, and a change in femorotibial rotation from internal to external with LFTS and TR stifle management as compared to the CrCL-deficient stifle. This study demonstrates how computer modeling can be used to evaluate biomechanics of stifle stabilization surgical techniques.

Medial patellotibial ligament and medial patellomeniscal ligament: anatomy, imaging, biomechanics, and clinical review.

The purpose of this article is to review anatomical, biomechanical, and clinical data of the medial patellotibial ligament (MPTL) and medial patellomeniscal ligament (MPML), as well as studies focusing on the medial patellofemoral ligament (MPFL) but with relevant data about the MPTL and MPML. A literature search of articles specifically addressing the MPTL and/or MPML was included along with studies focusing on the MPFL but with relevant data about the MPTL and MPML. The medial patellar ligaments responsible for maintaining the stability of the patellofemoral (PF) joint include the MPFL, the MPTL, and the MPML. The MPFL is considered the primary restraint to lateral patellar translation, while the latter two are considered secondary restraints. There is robust literature on the anatomical, imaging, and biomechanical characteristics of the MPFL, and also the clinical outcome of its injury and surgical reconstruction; much less is known about the MPTL and MPML. Isolated MPFL reconstruction has good clinical and functional outcomes, with a low failure rate when defined as frank re-dislocation. Complications, including continued episodes of patellar apprehension and subluxation, remain present in most series. In addition, the current literature primarily includes a homogeneous population with few excessive anatomic dysplastic factors. There is lack of knowledge on the role of MPTL and MPML in (potentially) aiding patella stabilization and improving clinical outcomes. Understanding the role of the medial-sided patellar ligaments, in particular the role of the secondary stabilizers, in PF function and injury will aid in this goal. MPTL and MPML have consistent basic science literature, as well as favorable clinical outcomes of surgical patellar stabilization with reconstruction of the MPTL. However, there is much heterogeneity among clinical case series and lack of comparative studies to allow clear indication for the role of isolated or combined surgical reconstruction in patellar stabilization. Therefore, this comprehensive review helps understand the current knowledge and the possible applications in the orthopedic clinical practice. V.

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.

New Technique for Medial Patellar Desmotomy in Cattle and Donkeys

The present technique is designed to transect the medial patellar ligament indicated for treatment of upward fixation of patella in cattle and donkeys. A medial patellar desmotomy was performed first on cadavers and then on 21 live cattle or donkeys. In live animals under local anesthesia, a sterile silk strand (USP 1) mounted on a curved needle is inserted through skin at the medial aspect of the medial patellar ligament to the subcutaneous fascia and directed beneath the ligament to emerge at opposite side. The silk is then sawed to cut the ligament. In contrast to other procedures, the desmotomy is less invasive as skin at the surgical site is not incised, pericapsular fat and joint capsules not invaded, and the ligament is fully transected in a one-step procedure. Minimal tissue invasiveness limited infection of surgical site, minimized bleeding, and decreased related postoperative consequences.

Modified Technique for Medial Patellar Desmotomy in Donkey (Equus acinus)

In our study, a modified technique of medial patellar desmotomy in donkey was performed on 10 apparently adult healthy alive donkeys of both sexes in addition to other two cadavers. In concern to the upward fixation of the patella in donkeys as native animals in Upper Egypt which recorded high incidence of the disease more than found in northern areas. Medial patel- lar desmotomy is the preferable sur- gical procedure of choice for treating such problem. Contrary to the stand- ard technique of treatment, the study aimed to introduce a modified easier, less expensive and field applicable desmotomy method. Our study gives a full detailed applied anatomical description of the patellar ligaments specially the medial one as well as its boundaries; osseous and muscular attachment as well as the extension of the joint capsule. The medial patellar ligament was the longest and the weakest among others on the other hand the middle one was the shortest and of considerable thickness. The best and ideal side for desmotomy was determined in order to avoid massive drawbacks as piercing the joint cap- sule or even cutting the tendon of the sartorius muscle. Generally nearly similar anatomical results were ob- served with the most of authors and the donkey was an ideal animal in equine experiment and the study al- low the anatomists for further com- parative anatomical researches.

A Biomechanical Comparison of Isometric and Anatomic Medial Patellofemoral Ligament Reconstruction.

The purpose of this study was to compare two different methods of medial patellar femoral ligament (MPFL) reconstructions: isometric and anatomic. These were then compared with the native MPFL. Fourteen fresh frozen cadaveric knees were carefully dissected to expose the MPFL. The patella was laterally translated 10 mm using an Instron and values were recorded for the intact ligament and the reconstructions. Neither the anatomic nor the isometric reconstructions completely restored the biomechanical properties of the intact MPFL. There were fewer differences between the isometric reconstruction and the intact specimens. The higher forces and stiffer constructs that occurred with the anatomic reconstruction may suggest that this reconstruction technique could overconstrain the patellofemoral joint.

Ultrasonographic Findings in the Stifle Joint of Active Jumping and Dressage Horses

Objective Ultrasonography (US) is frequently used to evaluate the equine stifle joint. Some soft tissue US findings are known to be clinically relevant, while others are considered incidental. These considerations are not always evidence-based. This study aims to describe the US findings observed in the stifle of clinically sound, active jumping and dressage horses. Design: Prospective study Animals: 46 Warmblood horses Procedures: To be included in this study, the horses had to fulfil 4 criteria: (1) in competition at least 1 time/month at national or international level, (2) in full work, (3) free of lameness, (4) no complains of the horse’s performances. Both stifle joints of each horse were scanned systematically by US and US findings were recorded. Results: 46 Warmblood horses fulfilled the criteria. US was normal in 21 horses, whereas abnormalities were detected in one or both stifles in 7 and 18 horses, respectively. Changes were seen in all compartments of the stifle joints: medial femorotibial joint (18 horses): osteophytes, effusion, subchondral cyst in the medial femoral condyle and lesions in the cranial meniscotibial ligament or medial collateral ligament; lateral femorotibial joint (4 horses): mild effusion, subchondral cyst in lateral femoral condyle; femoropatellar joint (16 horses): effusion, lesions in medial or intermediate patellar ligament or osteochondrotic lesions. Conclusion and Clinical relevance: Mild changes can be found ultrasonographically in the stifles of sport horses. Periarticular new bone formation was observed in 25% of the horses, apparently clinically not relevant. Lesions in the menisci, the tendinous portions of the popliteus muscle, long digital extensor muscle or peroneus tertius muscle or the lateral collateral ligament were not observed.

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.

Systematic arthroscopic investigation of the bovine stifle joint

The objective of the present study was to establish a protocol for arthroscopic exploration of the bovine stifle joint using craniomedial, caudolateral and caudomedial approaches. An anatomic and arthroscopic study using 26 cadaveric limbs from 13 non-lame adult dairy cows was performed. The craniomedial approach was created between the middle and medial patellar ligaments to investigate the cranial pouches of the stifle joint. The inter-condylar eminence, the proximal aspect of the medial femoral trochlear ridge and the lateral aspect of the lateral femoral condyle were used as starting points for systematic examination of the medial femorotibial, the femoropatellar and the lateral femorotibial joints, respectively.The observed structures were: the suprapatellar pouch, articular surfaces of the patella, femoral trochlear ridges, cruciate ligaments, menisci, and the meniscotibial ligaments. The arthroscopic portal for the caudomedial femorotibial pouch was about 6–8 cm caudal to the medial collateral ligament. The proximal and distal caudolateral femorotibial pouches were explored 3 cm and 1.5 cm caudal to the ipsilateral collateral ligament, respectively. The observed structures were the caudal aspect of femoral condyles, menisci, caudal cruciate ligament, popliteal tendon and the meniscofemoral ligament. Restricted joint size and risk of common peroneal nerve damage were the major limitations for exploration of the caudal femorotibial compartments. The study described the arthroscopic portals and normal intra-articular anatomy of the bovine stifle joint but further investigations are warranted to validate these techniques in clinical cases.

Medial patellar ligament splitting in horses with upward fixation of the patella: A long-term follow-up.

Medial patellar ligament splitting (MPLS) has been shown to be a highly effective and minimally invasive treatment for upward fixation of the patella (UFP) in horses. However, long-term follow-up results of this procedure have not previously been reported. To evaluate the long-term resolution of UFP following MPLS and provide information on complications and recurrence. Retrospective case series. Data were collected from horses that underwent MPLS between 1999 and 2013. All cases had a confirmed diagnosis of UFP that had not responded to conservative therapy. Data were collected from medical records, including follow-up visits and through telephone conversations with the owner, trainer or referring veterinarian. A total of 85 horses were included. Fifty-eight horses (68%) had surgery under general anaesthesia in dorsal recumbency, while 27 horses (32%) underwent standing surgery and 97.6% had complete resolution of the UFP immediately after surgery or within the 2 week rehabilitation period. Two cases (2.4%) had only unilateral resolution after bilateral surgery, even after the procedure was repeated. The majority of cases (90.5%) were followed up at least 3 and up to 14 years after surgery. No short- or long-term complications were reported. No recurrence of UFP was observed in the horses that resumed exercise after surgery. Medial patellar ligament splitting is a highly effective and minimally invasive surgical procedure to treat UFP when conservative treatment is unsuccessful. In addition, it allows for a very rapid return to sports activity. No short- or long-term complications were observed and no recurrence of this condition was noted.

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.

Histopathological evaluation of medial patellar ligament and radiographic evaluation of the stifle joint of upward fixation of patella affected bovines

Aim: To evaluate the medial patellar ligament by histopathology and stifle joint by radiography of upward fixation of patella affected bovines. Materials and Methods: Present study was conducted on 24 clinical cases of bovines. Out of twenty four clinical cases of upward fixation of patella, twelve were buffaloes, six were cows and remaining six were bullocks. Histopathological evaluation of medial patellar ligament from the affected animals and radiographic evaluation of stifle joint were done as per standard procedure. Results: Histopathological observations were made as follows. Nuclei of the fibroblasts were oval shaped and hypertrophied, as compared to thin, elongated normal nuclei. There was an excessive proliferation of fibrous connective tissue. There was a presence of mononuclear cells and fibrin exudates in the surrounding loose connective tissue of the ligament and medial coat of the blood vessels of medial patellar ligament was thickened. Plain radiographs that were taken in the medio-lateral view did not reveal any evidence of upward or dorsal deviation of patella in relation to the femoral condyle. Conclusions: Histopathological evaluation of the medial patellar ligaments of upward fixation of patella affected bovines showed various pathological changes, while radiography of the stifle joint did not confirm the condition.

Long-term Outcome of Standing Medial Patellar Ligament Splitting to Manage Horses Exhibiting Delayed Patellar Release: 64 Horses

A standing surgical technique for splitting the medial patellar ligament is described, and the long-term (average 4.5-years) efficacy of the procedure in horses exhibiting delayed patellar release is reported. Medical records of 64 horses that underwent a standing medial patellar ligament splitting surgery performed to treat delayed patellar release were analyzed retrospectively. Horses were sedated in standing stocks. A number 15 scalpel blade was used to percutaneously split the medial patellar ligament from just proximal to its insertion on the tibial tuberosity to its attachment on the parapatellar fibrocartilage, with the goal of inducing a localized desmitis and subsequent thickening of the ligament. Aftercare consisted of oral antibiotics, 14 days stall rest with hand walking, light exercise for 14 days, and full work at 4 weeks. Follow-up information was obtained through telephone calls to owners and/or clinical evaluation by a veterinarian. Results showed that 89% of horses benefitted from the procedure, with complete resolution in 58% of horses and improvement in 31% of horses. A total of 73% of horses were able to perform at the desired level following the procedure; 63% of horses showed signs of improvement or resolution within 30 to 60 days. Two horses had complications following the procedure: 1 horse had an incisional infection, and 1 had a medial patellar ligament rupture. This study shows that standing medial patellar ligament splitting is a successful, long-term surgical option for treatment of delayed patellar release. The procedure has few complications and allows rapid return to desired performance.

Isolated Medial Patellar Femoral Ligament Reconstruction for Recurrent Patella Dislocation: A Prospective Cohort Study

Isolated Medial Patellar Femoral Ligament Reconstruction for Recurrent Patella Dislocation: A Prospective Cohort Study

Ultrasonographic and radiographic diagnosis of patellar fragmentation secondary to bilateral medial patellar ligament desmotomy in a Warmblood gelding

Ultrasonographic and radiographic diagnosis of patellar fragmentation secondary to bilateral medial patellar ligament desmotomy in a Warmblood gelding

EMPREGO DE DESMÓTOMO ESPECIAL NO TRATAMENTO CIRÚRGICO DA FIXAÇÃO DORSAL DE PATELA EM BOVINOS

Upward fixation of patella is a disease observed in large animals and it occurs in bovines in unilateral or bilateral form, affecting male and female, different breeds and usually adults. The aim of this study was to evaluate the efficiency of an special surgical instrument designed for surgical treatment of upward fixation of patella in bovines, compare the results to those obtained applying the usual incision technique for this disease and to evaluate the post-operative period. It was submitted to medial patellar desmotomy, 32 UFP carrier female bovines with unilateral form, divided in four groups with eight animals each (GI, GII, GIII and GIV). After 12 hours of fasting, sedation with 2% xylazine, restraining in lateral recumbency and local anesthesia with 2% lidocaine on medial patellar ligament, the bovines from GI and GII were submitted to desmotomy after 4 cm length skin incision. In animals from groups III and IV, it was proceeded skin incision of 0.5 cm, followed by section gracile and sartorium muscles fasciae and desmotomy with stainless steel instrument developed for this purpose. To visualize the desmotomy with this surgical instrument, it was used, experimentally, the video-surgery. For skin closure it was used 2-0 cotton thread in animals from groups I and II. In postoperative period, bovines from groups I and III received antimicrobial drugs and it was evaluated during 28 days the occurrence of edema, wound dehiscence, abscess formation, granuloma and cicatricial evolution of the surgical wound in the animals from all groups. It was not detected any difference concerned to the use of antimicrobiane drug. Edema, wound dehiscence and abscesses occurred on the bovines from GI and GII and the clinical healing was earlier on the animals from GIII and GIV. All animals healed, but the designed instrument allowed more quick and less invasive interventions, witch leaded to minor postoperative complications. Key words: Cows, desmotomy, locomotion system, surgical material.

Proprioception in the ACL-ruptured knee: The contribution of the medial collateral ligament and patellar ligament. An in vivo experimental study in the cat

In the absence of anterior cruciate ligament (ACL), secondary restraints such as menisci, ligaments, and tendons restrict anterior knee laxity. Strain detection at these sites could define the contribution of this alternative signalling system to knee proprioception after ACL injury. The hypothesis in this study questions if measurements of anterior tibial translation (ATT) from surface strain gauges on the insertions of the medial collateral ligament (MCL) and the patellar tendon (PT) are sufficiently sensitive and specific to differentiate normal, stable knees from acutely unstable knees due to ACL section. Twelve cats received miniaturized strain gauges on the surface of MCL and PT distal insertions. A purpose-made receiver transformed into measurements any voltage variation obtained during passive knee flexion–extension and anterior tibial translation manoeuvres. Variables under evaluation included first peak latency, normalized amplitude, and slope of voltage along time. Femorotibial displacements were video recorded, digitized, and used as the ATT reference. The proposed system detected significant changes in the slope of the voltage/time signal, with higher specificity and sensitivity during ATT after experimental ACL section. Changes were not significant during flexion or extension. It was found that a pattern of earlier and more intense strain in MCL and PT distal insertions was found during ATT in the ACL deficient knee. Enhanced pattern recognition learning from these structures could be a future target for proprioceptive training after ACL injury.

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