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At least 613 records · Page 34Linked to original sources
PubMedDate not supplied

Clinical characteristics of patellar disorders in young athletes.

The clinical histories of 50 young athletes who complained of patellar instability or pain were analyzed, and their physical findings were compared to those of 50 controls. The patients were divided into three groups, based on their symptoms. Analysis of their physical findings confirmed the validity of these divisions. Those who complained of frank dislocation of the patella exhibited the most pronounced stigmata of quadriceps dysplasia, including vastus medialis deficiency and infrapatellar fat pad enlargement, and had increased general ligamentous laxity, increased mean patellar mobility, and out-facing patellae with concomitantly decreased Q angles in chronic, recurrent cases. Patients who complained of the classic patellar pain pattern, often called "chondromalacia patella," but who denied swelling were designated CMP. They had normal mean ligamentous laxity and mean patellar mobility, an increased incidence of in-facing patellae with concomitantly increased mean Q angle, and frequently palpable lateral patellofemoral bands. Patients who complained of pain and swelling had physical findings intermediate to the other two groups, and generally correspond to what is usually termed subluxation of the patella. They exhibited normal general laxity but increased mean patellar mobility, normal mean Q angle but an increased incidence of patellar infacing, and fat pad enlargement.

Adult↗
PubMedDate not supplied

Treatment of patellofemoral instability in childhood with creation of a femoral sulcus.

Four patients with six knees with patellofemoral instability and severe trochlear dysplasia were treated with creation of a femoral sulcus. None of the six knees have had recurrent dislocations at 3- to 11-year follow-up. All patients had chromosomal abnormalities and limited motor demands. We recommend this procedure for children with patellar instability refractory to standard treatment methods who have severe trochlear dysplasia and limited motor demands.

Adolescent↗
PubMed1997

Survivorship analysis of cementless meniscal bearing total knee arthroplasty.

Four hundred seventy-three consecutive cementless cruciate retaining meniscal bearing primary total knee replacements were done on 375 patients from May 1985 to February 1991. These were observed for a 10-year period (average, 5 years). Seventeen (3.6%) required change of components because of mechanical failure. There were 12 polyethylene fractures or dislocations. There were 5 tibial subluxations secondary to ligamentous instability occurring at an average of 21 months postoperatively. There were 2 component loosenings secondary to bone graft resorption (1 femoral, 1 tibial). There were 5 infections (4 Staphylococcus aureus, 1 Pseudomonas). Significantly, with the exception of the 2 knees with bone graft resorption, there was no component (femoral, tibial, or patellar) loosening. Kaplan-Meier survival estimates, using as an endpoint of revision surgery for any mechanical reason (polyethylene breakage, polyethylene dislocation, or ligamentous instability), showed a survivorship of 94.6% at the 8-year interval. Survivorship related to mechanical loosening of fixation of any component at the 8-year interval was 99%.

Adult↗
PubMed1997

The Rotaflex total knee replacement--a 5 year review.

We report the results of a retrospective analysis of 43 patients who received 56 Rotaflex total knee arthroplasties, with a mean follow-up of 55.7 months. The British Orthopaedic Association (BOA) knee assessment protocol was used in evaluating the clinical results. Two patients could not receive post-operative scores. In the remaining 54 knees, the mean pre-operative score was 25.6, improving to 30.8 post-operatively. Ten knees showed a decrease in knee score, two were unchanged and 42 improved. The greatest improvements were in pain relief and maximum flexion. Wound infection and dehiscences were common, the latter requiring further surgery in five cases. Later, there were eight fractures involving the prosthesis, seven dislocated or subluxed patellae, two deep infections and three cases of severe aseptic loosening. A common feature was severe patellar wear, due to the design fault of an absent femoral groove. The high rate of complications and poor functional result of the Rotaflex knee preclude its use in current practice.

Activities of Daily Living↗
PubMedDate not supplied

Soft tissue restraints to lateral patellar translation in the human knee.

The purpose of this investigation was to identify and quantify the soft tissue restraints, both medially and laterally, to lateral patellar translation. These restraints to lateral patellar translation at 20 degrees of knee flexion were tested biomechanically on a universal testing instrument in nine fresh-frozen cadaveric knees. After preconditioning the tissues, the patella of each intact knee was translated laterally to a distance at which a force of 200 N was recorded. This distance was used to translate the patella for the remaining structures to be sectioned. The contribution of each structure to the total restraining force was determined as the percent of the force to restrain the intact specimen by sectioning the restraints in a predetermined order. The contribution of each structure to the restraining force was defined as the difference between the restraining force before and after its sectioning. The medial patellofemoral ligament was found to be the primary restraint to lateral patellar translation at 20 degrees of flexion, contributing 60% of the total restraining force. The medial patellomeniscal ligament contributed 13% of the total force, and the lateral retinaculum contributed 10%. The medial patellotibial ligament and superficial fibers of the medial retinaculum were not functionally important in preventing lateral translation. The previously unrecognized contribution of the lateral retinaculum as a restraint to lateral patellar translation may shed new light on the failures of isolated lateral release for acute lateral dislocation of the patella.

Adult↗
PubMed1984

The treatment of patellar instability by lateral release.

A simple procedure of using a Smillie knife to release the lateral patellar retinaculum and the capsule in the unstable patella syndrome is described. The syndrome includes recurrent dislocation, recurrent subluxation and acute dislocation of the patella. Arthroscopy, to exclude any other pathology such as chondromalacia patellae, is performed before proceeding to closed lateral release. The results of this procedure are as good as those after more major surgical procedures. In a small percentage of patients a second operation such as tibial tubercle transfer or patellectomy may be necessary, especially in patients with an underlying congenital abnormality; but in many patients this type of major surgery has proved unnecessary.

Adolescent↗
PubMed1995

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

PURPOSE: To characterize the magnetic resonance (MR) imaging features of patellar tendinitis. MATERIALS AND METHODS: Fifteen patients with a clinical diagnosis of patellar tendinitis underwent gadolinium-enhanced MR imaging of the knee. RESULTS: 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. CONCLUSION: Patellar tendinitis demonstrates a consistent spectrum of changes at MR imaging that can aid understanding of the origin and treatment of damage.

Adolescent↗
PubMed2004

[Dislocation of the proximal tibio-fibular joint due to severe leg and knee trauma].

PURPOSE OF THE STUDY: Dislocation of the proximal tibio-fibular joint is a rare lesion generally described in athletes. In our experience, high-energy trauma in traffic accident victims was a frequent cause. Dislocation of the proximal tibio-fibular joint is generally described as anterolateral, posteromedial, superior, or subluxation. We describe an inferior form of dislocation. MATERIALS AND METHOD: The study population included eight men aged 21-55 years (mean 31 years). One patient had bilateral dislocation. There were four superior, one posterior, and four inferior dislocations. All patients also had an associated fracture of the tibia which was an open fracture in eight cases. Five patients suffered a lesion to the common fibular nerve. Three had tibial nerve involvement in a context of inferior disclocation. The lateral collateral ligament was torn in six cases. The central pivot was involved in four. Two patients had an avulsion of the patellar ligament on the tibial tuberosity. Five patients had vessel damage. Three required emergency amputation. Two patients (one superior and one inferior dislocation) underwent emergency bypass surgery but required below-knee amputation later due to persistent ischemia. All dislocations, excepting the one case of complete fibular avulsion and one emergency above knee amputation were treated by transarticular screw fixation of the proximal tibio-fibular joint. RESULTS: Mean follow-up was 5.8 years (1-9 years). At last follow-up, there were no cases of instability or pain in the proximal tibio-fibular joint. The patient with an initial neurapraxia in territory of the common fibular nerve recovered totally. The five amputated patients had prostheses and walked without crutches. DISCUSSION: Dislocation of the proximal tibio-fibuilar joint is a rare entity, but the frequency is probably underestimated. The dislocation can go unrecognized in patients with multiple injuries. Careful search should nevertheless be undertaken due to the risk of secondary involvement of the common fibular nerve. The Harrisson and Hindenach classification, inspired by the Lyle classification, does not mention inferior dislocation of the proximal tibio-fibular joint, a recently described entity. Our series included dislocations resulting from high-energy trauma associated with numerous ligament, nerve, and vessel injuries. In this context, dislocation of the proximal tibio-fibular joint constitutes an epiphenomenon.

Adult↗
PubMedDate not supplied

Kinematic MRI of the knee using a specially designed positioning device.

To evaluate the benefits of a specially designed positioning device, kinematic MR studies of the patellofemoral joint and the cruciate ligaments were performed. Handling of the device and positioning of the patient's leg were easy and took only a few minutes. The positioning device was helpful for patients to guide their joint motion and to obtain sufficient image quality for kinematic MR studies of both cruciate ligaments and the patellar tracking.

Adult↗
PubMed2000

Diagnosis and surgical repair of patellar luxations in a flock of sheep.

Eleven sheep with a common ancestry were evaluated for clinical signs of hind limb lameness. Physical examination revealed advanced forms of patellar luxation. Radiography confirmed the diagnosis of patellar luxation; flexed dorsoproximal-dorsodistal radiographic views were obtained and revealed hypoplasia of the femoral trochlea. Because of the advanced form of patellar luxation and trochlear hypoplasia, surgical intervention was recommended in the form of recession trochleoplasty and a modified tibial tuberosity transposition, along with imbrication and releasing incisions. Sheep may have a genetic predisposition for patellar luxation.

Animals↗