Medial Retinaculum Research Articles

The Diagnostic Validity of Magnetic Resonance Imaging in Acute Knee Injuries With Hemarthrosis: A Single-Blinded Evaluation in 69 Patients Using High-Field MRI Before Arthroscopy

Sixty-nine patients with traumatic knee hemarthrosis were evaluated an average of 3 days after trauma by high field (1.5T) magnetic resonance imaging (MRI) using sagittal T1, T2-weighted and coronal 3D-gradient echo images. All knees were arthroscopically examined shortly afterwards. The diagnostic validity of MRI for intraarticular pathology was determined using arthroscopy as golden standard. All patients had pathological findings on arthroscopy. The injuries were sports-related in 77% of the cases. MRI was highly sensitive (86%) and specific (92%) for diagnosis of anterior cruciate ligament tears. Diagnosis of medial meniscal tears showed a 74% sensitivity and 66% specificity. MRI detected lateral meniscal tears in 50% with an 84% specificity. As such, MRI missed 10 significant meniscus ruptures requiring surgical treatment. The sensitivity for partial or total medial collateral ligament tears was 56%, the specificity 93%. Rupture of the medial retinaculum in cases with patellar dislocation or significant damage of articular cartilage were only detected by MRI in a few cases (27% and 20% sensitivity, respectively). MRIs low diagnostic validity for intraarticular pathology with hemarthrosis may be attributed to the shifting paramagnetic properties of the blood remains and catabolic processes in meniscal and chondral tissues during the hemoglobin degradation process. Accordingly, MRI, with the technique used, could neither replace arthroscopy in the diagnosis and screening of acute knee injuries, nor select patients with need for immediate arthroscopic meniscal surgery.

Patellar tendinitis: MR imaging features, with suggested pathogenesis and proposed classification.

To characterize the magnetic resonance (MR) imaging features of patellar tendinitis. Fifteen patients with a clinical diagnosis of patellar tendinitis underwent gadolinium-enhanced MR imaging of the knee. Grades of patellar abnormality, based on findings in the enthesial region at MR imaging, correlated with signs of increasing fibrovascular repair: grade 1 (n = 4), enhancing area adjacent to patellar apex, with marginal zone of intermediate signal intensity, and a patellar apical chondral-bone avulsion; grade 2 (n = 5), same signs as grade 1 damage but without avulsion; grade 3 (n = 6), homogeneous, nonenhancing area of intermediate signal intensity adjacent to the patellar apex seen on all images. Changes were most obvious posteriorly and involved the central and medial thirds of the tendon. Chronic injury to the medial retinaculum was a common associated finding. Patellar tendinitis demonstrates a consistent spectrum of changes at MR imaging that can aid understanding of the origin and treatment of damage.

Stellenwert der MR-Tomographie bei traumatischen Patellaluxationen

To describe the MR imaging findings in patients with lateral patellar dislocation. The MRIs of 31 patients with patellar dislocation were evaluated retrospectively. Arthroscopic surgery was performed in 23 cases. Hemarthrosis was found in 30/31, contusions of the lateral femoral condyle in 30/31 and of the medial patellar facet in 26/31 cases. Injury of the medial patellar retinaculum was seen in 28/31 cases. Osteochondral fractures were found in 18 patients; compared to arthroscopy there were one false-positive and 5 false-negative findings concerning loose cartilage bodies. In 7 cases, patellar dislocation was not suspected before MR imaging. Hemarthrosis, lateral femoral and medial patellar contusion, and retinacular disruption are typical findings after lateral patellar dislocation. A careful search for free osteochondral fragments is mandatory as it influences the indication and performance of arthroscopic surgery.

Acute dislocation of the patella: MR findings.

The authors describe magnetic resonance (MR) imaging findings of acute traumatic dislocation of the patella. MR imaging at 0.1 T was performed in 25 patients with an acute patellar dislocation, 24 of whom underwent surgery. All patients were young male conscripts, aged 18-22 years. Signal intensity abnormalities of bone, seen as areas of decreased signal intensity on T1-weighted images, were found in all 25 patients (100%). The lateral femoral condyle was involved in all cases. Signal intensity changes also appeared in the patella in eight patients and in the lateral tibial plateau in three. Osteochondral fragments seen at plain radiography and cartilage fissuring noted at arthroscopy were not visible at MR imaging. Injury of the medial patellar retinaculum was seen at MR in each case. All patients had a joint effusion. Lateral subluxation of the patella was a common finding. Constant findings at MR imaging were (a) contusion of the lateral femoral condyle, (b) tear of the medial retinaculum, and (c) joint effusion.

Diastasis of Bipartite Sesamoids of the First Metatarsophalangeal Joint

Injury to the metatarsophalangeal (MP) joint of the great toe, often termed "turf-toe", is a common occurrence in football. We have identified four cases of first MP plantar capsular injury with diastasis of a bipartite sesamoid. In three cases, observation and protection resulted in progressive widening of the fragments associated with pain and disability. These players required resection of the distal sesamoid fragment and repair of the volar capsule. The fourth player underwent acute repair of the medial retinaculum and capsule. All players have had a full return to sports activity. Diastasis of components of a partite sesamoid provides objective evidence of disruption of the plantar capsular mechanism. Early recognition of this condition confirmed by stress radiographs is recommended. Treatment may include early protection followed by resection, if painful, or acute repair of the retinaculum. Previous descriptions of turf-toe have not included injuries to the sesamoid complex of the first MP joint. In our opinion, the term turf-toe should represent the consequences of a hyperextension injury to the first MP joint in which the volar capsule has been disrupted proximal to the sesamoid. A classification for first MP joint injuries is presented.

Transient lateral patellar dislocation: diagnosis with MR imaging.

Transient lateral patellar dislocation is frequently difficult to diagnose accurately on the basis of clinical findings. Accordingly, we studied the MR findings in 26 cases to determine if MR imaging is useful in establishing the diagnosis. A retrospective review of 1450 MR examinations of acutely injured knees was performed to determine the MR findings resulting from transient lateral patellar dislocation. A distinctive constellation of MR findings reflecting the known mechanism of injury indicative of transient lateral patellar dislocation was found in 26 patients. Patellar dislocation was not clinically suspected before imaging in 19 (73%) of these 26 patients; most patients had been referred for suspected injury of the cruciate ligaments or menisci. Axial, sagittal, and coronal MR images were obtained in all patients, and all had clinical follow-up. Correlation of MR findings with surgical findings was possible in six. Specific components of the constellation of MR findings included disruption or sprain of the medial retinaculum in 25 (96%) of 26 patients, lateral patellar tilt or subluxation in 24 patients (92%), lateral femoral condyle contusion in 21 patients (81%), osteochondral injury in 15 patients (58%), and joint effusion in all 26 patients (100%). Concomitant injury to major ligaments or menisci was present in eight (31%). Our findings suggest that patients with transient lateral patellar subluxation have a distinctive constellation of MR findings that can be used to distinguish this entity from other common knee injuries.

Arthroscopically assisted proximal extensor mechanism realignment of the knee

An arthroscopically assisted proximal extensor mechanism realignment procedure has been designed and performed on 27 knees in 24 patients. The study group has been followed a minimum of 18 months. The procedure consists of a lateral retinacular release and an arthroscopically controlled plication of the medial patellar retinaculum and oblique fibers of the vastus medialis. The indications for this procedure include recurrent patellar instability and acute initial patellar dislocation with a concomitant fracture of either the patella or lateral margin of the intertrochlear sulcus. Using a simple subjective rating system for the patellofemoral joint, 25 of the 27 knees (92.5%) were subjectively rated good or excellent by the patient. Objective criteria also indicated a high success rate. There were two recurrent subluxations. There were two relatively minor complications. The average time for return to full presurgical activities, including previous sports, was 4 months.

The Use of Polypropylene Mesh for Revision of Failed Repair of Superficial Digital Flexor Tendon Luxation in Three Dogs

Polypropylene mesh was used to reinforce the medial calcaneal retinaculum in three dogs which required revision of failed repair of superficial digital flexor tendon luxation. All three dogs were sound at follow-up examination three months after surgery.

Surgical treatment of habitual dislocation of the patella in childhood

Surgical Principles Medial displacement of the medial half or the medial two thirds of the patellar ligament on the proximal tibia; the detached ligament is anchored to a chiselled trough in the bone with a cancellous bone screw and serrated washer. Division of the fibres of the tractus iliotibialis leading into the patella and of the lateral extensor retinaculum up to the vastus medialis (so-called “lateral release”). Transfer of the vastus medialis in lateral and distal direction by approximately 1 to 1.5 cm onto the patella. Double breasting of the medial extensor retinaculum.

Bilateral acute knee ligament injuries (2 case report)

The lesions were found to be bilateral in two of the patients who were admitted to our clinic for traumatic knee injuries. First patient was a 22 year old female. Physical and radiological examinations revealed that she had ruptures of the ACL+LCL in her right knee, ACL and MCL in her left knee. She had been operated on at two sessions; first for the primary repairs of the ACL and LCL ruptures of the right knee and second for the primary repairs of the ACL and MCL ruptures of the left knee. Follow-up period is 24 months. According to the Lysholm knee scale her scores for both knees are 98 and according to the Marshall knee scale scores for her both knees are 44. The second patient was a 16 years old male and came after a traffic accident. He had ruptures of the ACL, LCL and the joint capsule in her Ieft knee and right tibiofemoral luxation together with MCL,ACL, PCL and posterior oblique ruptures, total peripheral tears of the medial meniscus and tears of the medial retinaculum. ACL and repairs of the left knee and primary repairs of all torn Iigaments and structures were performed after reposition of the Iuxation of the right side. The follow-up period is 7 months in this patient with a Lysholm score of 68 for both knees. The Marshall score is 29 on the right and 35 on the Ieft.

Acute dislocation of the patella

We report a prospective study of 55 patients with acute primary patellar dislocation, all treated by operation and followed up for at least two years. Diagnosis was based on the history of a lateral displacement, with medial tenderness and a positive apprehension test; redislocations were excluded. Before operation, the difference in lateral shift on skyline views of the injured and control patellae was highly significant. At operation, rupture of the medial retinaculum of the patella was seen in all but one case. There were medial marginal fractures of the patella in 23 cases. Subjective results of the operation were excellent or good in 44 of the 55 at two years with a redislocation rate of only 9%. Most patients were able to return to the same level of sporting activity as before the injury.

Pathologie, Diagnose und Therapie von Patellaluxationen

Patella dislocation in sports trauma is a common injury and is influenced by minor alterations or derangements of dynamic or static factors. The sulcus angle should not exceed 138 degrees and the Q angle should not be more than 15 degrees. Patella alta has some influence on the dislocation tendency, and so has weakness and atrophy of the musculus vastus medialis obliquus, causing muscular imbalance. Diagnosis is made via x-ray in tangential as well as a.p. and lateral view. Clinical examination of the patella reveals in lateral dislocation or redislocation can be provoked after positioning. Tenderness is present along the medial retinaculum associated with haemarthrosis in most of the cases. Conservative treatment includes evaluation of haemarthrosis and physiotherapy especially with regard to strengthening the vastus medialis obliquus. Surgery includes lateral release and medial capsular plication or transposition of the patellar tendon for correction of the Q-angle.

Acute dislocation of the patella. A prospective review of operative treatment

We report a prospective study of 55 patients with acute primary patellar dislocation, all treated by operation and followed up for at least two years. Diagnosis was based on the history of a lateral displacement, with medial tenderness and a positive apprehension test; redislocations were excluded. Before operation, the difference in lateral shift on skyline views of the injured and control patellae was highly significant. At operation, rupture of the medial retinaculum of the patella was seen in all but one case. There were medial marginal fractures of the patella in 23 cases. Subjective results of the operation were excellent or good in 44 of the 55 at two years with a redislocation rate of only 9%. Most patients were able to return to the same level of sporting activity as before the injury.

Ｎａｉｌ‐ｐａｔｅｌｌａ Ｓｙｎｄｒｏｍｅの膝障害について

We have found three patients with nail-patella syndrome. A 17-year-old female with parmanent dislocations of the patella bilatrally had hypoplastic patellae in addition to hypoplasia of the lateral femoral condyle. Reefing of the medial retinaculum, release of the lateral retinaculum of the patella and transposition of the tuberositus tibiae have led to good results.

Diagnosis and therapy of traumatic patellar dislocation in the athlete

Traumatic dislocations of the patella usually occur in sport activities. The review of our in-patient collective between 1980 and 1985 showed twenty traumatic dislocations of the patella among 1106 sport injuries. Most patients were adolescents. Seventeen of these injuries resulted from a typical valgus-flexion-external rotation-mechanism. Only three cases followed direct trauma. The therapy of choice in fresh traumatic dislocations of the patella in sportsmen is a suture of the medial retinaculum and if necessary refixation of osteochondral fragments. We performed operative treatment in sixteen of our own patients.

Arthroscopic repair of the medial retinaculum and capsule in acute patellar dislocations

Treatment for acute dislocations of the patella is highly controversial among many knee surgeons. This study proposes an arthroscopic technique for the surgical repair of the retinacular-capsular defects caused from acute patellar dislocation. The clinical material used involved 30 cases with no previous history of patellar instability and with history of documented lateral dislocation accompanied by an acute hemarthrosis. All individuals in this study were treated with arthroscopic medial capsular-retinacular repair and lateral retinacular release. The follow-up on these patients, ranging from 1 to 7 years postoperatively, revealed that the results of treatment were gratifying in all instances with the exception of one traumatic redislocation. It appears that the arthroscopic procedure used in this study was successful in stabilization of the acute dislocation of the patella, and that it is a beneficial addition to present surgical treatment for the acute dislocation of the patella. This technique provides early accurate diagnosis and, thus, early accurate restoration of normal anatomy. This technique is by no means the only way, but it it one way to obtain satisfactory results in the treatment of this most difficult problem.

Recurrent dislocation of the patella treated by the modified Roux-Goldthwait procedure. A prospective study of forty-seven knees.

We studied the results in forty-seven knees in thirty-seven patients - ten male and twenty-seven female - who had recurrent dislocation of the patella and were treated by a modified Roux-Goldthwait procedure (lateral retinacular release, medial transfer of the lateral patellar tendon without advancement, plication of the medial retinaculum, and advancement of the vastus medialis). Ten of the female patients had bilateral dislocation. The results were analyzed after follow-ups ranging from 3.0 to 16.3 years (average, 5.8 years). The study confirmed that a tangential radiograph of the patellofemoral joint, made with the knee in 20 degrees of flexion, is reliable in determining patellar displacement. The results were excellent in twelve knees, good in thirty-one, fair in one, and poor in three. The fair and poor ratings were due to pain caused by severe chondromalacia patellae. The patient with a fair result had had recurrent dislocations after the Roux-Goldthwait procedure due to a very lax synovial and capsular sac. Reoperation with tightening of the sac medially and laterally eliminated hypermobility of the patella in this patient and established straight patellar tracking. There was one serious complication, a large subcutaneous hematoma with necrosis of a skin flap. The patients with mild chondromalacia improved and showed no progressive patellofemoral arthritis after simple realignment, while those with severe chondromalacia were not improved by shaving, drilling, and realignment. Preliminary results indicated that a modified Maquet procedure, in addition to realignment, may be indicated for patients with severe chondromalacia. This study demonstrated that the modified Roux-Goldthwait procedure, without advancement of the tibial attachment of the patellar ligament, can stabilize the patella without increasing patellofemoral compression. The procedure does not relieve the symptoms of severe chondromalacia of the patella but realignment is the first step in treatment of any form of patellofemoral arthrosis.

Stressing on the human femoro-patellar joint. I. Components of a vertical and horizontal tensile bracing system.

Horizontal and vertical tensions act on the femoropatellar joint. In both knee joints of 60 human corpses the muscles and ligaments participating in the tensile bracing of the knee joint were studied macroscopically. While the structures acting in the vertical direction are very constant, the components participating in horizontal tensile bracing show large variations. Components of vertical tensile bracing are the quadriceps femoris muscle, the ligamentum patellae as well as the vertical patellar retinacula. The active part of horizontal tensile bracing consists of the medial and lateral vastus muscles. The passive components of this system are arranged in three layers. The superficial layer is formed by the fascia lata. The middle layer consists of the horizontal retinacula. A medial horizontal retinaculum was present in one third of our cases. It passes from the medial margin of the patella towards the medial femoral epicondyle. A lateral horizontal retinaculum is demonstrable in all cases studied. It passes horizontally from the lateral margin of the patella and inserts into the deep layer of the iliotibial tract. Insertion of the lateral horizontal retinaculum into the lateral femoral epicondyle was not observed in our material. The third layer is formed by ligaments supporting the joint capsule. These originate from the medial and lateral margin of the patella and pass towards their respective meniscus as well as variably towards the femoral or tibial condyle. These structures are found both medially and laterally in two thirds of the cases studied.

Patellar tendon rupture.

A patellar tendon rupture involves a complete tear of the tendon that runs from the patella's inferior pole to the tibial tubercle. It is typically seen in males in their third or fourth decade of life. It tends to result from an overall weakened tendon placed under high tensile forces. These tendon ruptures are best classified into acute versus chronic tears, depending on the time from rupture. This type of injury requires prompt diagnosis and surgical repair as the patellar tendon is a part of the extensor mechanism. The extensor mechanism of the knee is crucial to the function of the lower extremity, including ambulation. It is solely responsible for extending and straightening the knee and resisting knee flexion – a crucial aspect of standing with a flexed knee and, therefore, ambulation. Without a properly functioning knee extensor mechanism, the patient is severely limited functionally. Surgical intervention depends on the timing and location of the rupture. Acute ruptures are amenable to primary repair, whereas chronic ruptures often require tendon reconstruction. Anatomy The knee extensor mechanism is composed of the quadriceps muscle, quadriceps tendon, medial and lateral patellar retinaculum, patella, patellar tendon, and tibial tubercle.The quadriceps muscle is composed of four separate muscles with different origins but a common insertion point on the patella through the quadriceps tendon. Quadriceps Muscles with Origins Rectus femoris – anterior superior iliac spine and superior acetabular rim Vastus lateralis – greater trochanter and lateral linea aspera Vastus intermedius – proximal femoral shaft Vastus medialis – intertrochanteric line and medial linea aspera The medial and lateral patellar retinaculum are on their respective sides of the patella and are continuous with the vastus fascia to the tibia and the patella. They are minor patellar stabilizers and, if intact, can provide knee extension and straight leg raising despite a patellar or quadriceps tendon rupture.The patella is a sesamoid bone. It functions to increase the moment arm from the knee joint axis, thereby increasing the mechanical advantage and quadriceps pull in extension. The patella begins to engage the trochlea at 20 degrees of flexion and is fully engaged by 40 degrees of flexion. Joint reaction forces in the patellofemoral joint can be up to three times the body weight with stair climbing and seven times the bodyweight with deep bending.The patellar tendon, by definition, is a ligament as it connects bone (patella) to bone (tibial tubercle). The patellar tendon is approximately 30 mm wide by 50 mm long, with a thickness of 5 to 7 mm. The origin on the inferior pole of the patella is juxtaposed on the articular cartilage on the deep side and becomes confluent with the periosteum of the patella anteriorly. The tibial insertion is narrower and invests the entirety of the tibial tubercle, connecting the quadriceps muscles to the lower leg.

Operative procedures for the unstable patellae

Since 1977, the operative procedures were used variously in ten cases of the unstable patellae. According to Ficat, they were classified as follows, 1) recurrent dislocation: 5 cases 2) recurrent subluxation: 4 cases 3) permanent dislocation: 1 case.Their ages ranged from 15 to 43 years (average 20 years).There were 2 males and 8 females.The interaval between onset and operation averaged 64 months (1 month to 312 months).The diagnosis was determined by the clinical findings the hypermobility of the patella-Q angle, and the findings of the tangencial views of the patella, arthrography and arthroscopy.The operative procedures were used as follows, a): a) release of the lateral retinaculum and a tightening of the medial retinaculum and capsule; 1 case.b): a) and the procedure of Elmslie-Trillat; 7 cases.c): b) and semitendinosus transfer; 1 case.d): b) and McCarroll; 1 case.The follow up period ranged from 7 to 21 months and averaged 13 months. The results were rated according to the Ficat's criteria, consequently, 2 cases were exellent, 7 good, and 1 fair.