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Rapid recovery after oxford unicompartmental arthroplasty through a short incision.

Forty Oxford medial unicompartmental arthroplasties (UCAs) were performed through a short incision medial to the patellar tendon, without dislocation of the patella, using updated instruments (Oxford Knee Phase III, Biomet Ltd., Bridgend, UK). The rate of recovery of these knees (measured by the time taken to achieve straight-leg raising, 70 degrees of flexion, and independent stair climbing) was compared with that of 20 Oxford UCAs performed through an open approach with dislocation of the patella. Both groups were compared with 40 AGC (Biomet) total knee arthroplasties performed for osteoarthritis during the same time period. The average rate of recovery after the short-incision UCA was twice as fast as after open UCA and 3 times as fast as after total knee arthroplasty. Accuracy of implantation, assessed from 11 variables seen on fluoroscopically centered postoperative radiographs, was the same after UCA by the short-incision approach as after the open approach, suggesting that the short-term advantage of increased speed of recovery was gained without affecting the long-term results. We now employ the short incision with the phase III instruments for all UCAs.

Aged↗

How iliotibial tract injuries of the knee combine with acute anterior cruciate ligament tears to influence abnormal anterior tibial displacement.

A knowledge of the patterns of injury to the components of the iliotibial tract allows a clearer interpretation of motion limits testing in patients with abnormal anterior tibial translation of the knee (anterior cruciate ligament-deficient knees). Eighty-two consecutive patients with acute knee injuries were classified as anteromedial-anterolateral rotatory instability (anterior cruciate ligament-deficient) based on the abnormal motion demonstrated by clinical examination tests for instability. At surgery, injuries to the intraarticular and extraarticular anatomic structures were identified and correlated to the abnormal grades of motion demonstrated by the knee motion limits examination. Tears of the anterior cruciate ligament occurred in 80 (98%) of the knees. However, the grade of abnormal motion demonstrated by the Lachman and pivot shift tests was quite variable. This variation did not correlate statistically with anterior cruciate ligament tears. Injuries to the anatomic components of the iliotibial tract were confirmed in 76 (93%) of the knees. These injuries correlated highly with variations in grades of abnormal motion detected by the following tests: lateral joint line opening at 30 degrees (r2 = 0.05); Lachman test (r2 = 0.08); pivot shift (r2 = 0.16); and anterior translation at 90 degrees of flexion (r2 = 0.34). Thus, injuries to the components of the iliotibial tract are thought to contribute to the variation in grades of abnormal motion observed in this complex subgroup of anterior tibial translation instabilities.

Acute Disease↗

Patellar instability: assessment on MR images by measuring the lateral trochlear inclination-initial experience.

Lateral trochlear inclination (LTI) of the knee was compared on magnetic resonance (MR) images obtained in 30 patients with patellar instability (PI) and 30 patients with nonspecific internal knee derangement. Differences in LTI values between the two populations were significant (P <.001). Reproducibility of the measurement was judged excellent with an intraclass correlation superior to 0.98. Below a threshold value fixed at 11 degrees, LTI appears to be an excellent diagnostic test of PI with a sensitivity of 0.93 (28/30), a specificity of 0.87 (26/30), and an accuracy of 0.90 (54/60).

Adolescent↗

Lesion of the anterior cruciate ligament and sagittal disalignment of the knee in weight-bearing.

Twenty-nine patients with late reconstructive surgery for anterior cruciate ligament lesions had a clinical and radiologic follow-up ten years after injury. Anterior sagittal displacement of the tibia was recorded on the routine standing radiographs in 16 knees all having a normal femoro-tibial alignment in the non-weight-bearing position. Five of eleven patients with sagittal displacement of between 10 and 19 mm had early osteoarthrosis, which was confirmed by magnetic resonance imaging in four cases; their ages ranged from 23 to 38 years. No radiographic signs of osteoarthrosis were observed in those with displacements of less than 10 mm. In some patients there was a discrepancy between the clinical and radiographic measurements of instability. In addition to the clinical tests of instability standing rather than non-weight-bearing lateral radiographs are suggested for the routine assessment of cruciate ligament injuries.

Adult↗

Evaluation of patients with persistent symptoms after lateral retinacular release by kinematic magnetic resonance imaging of the patellofemoral joint.

The arthroscopic lateral retinacular release is typically performed to treat patellar pain and instability. This procedure was previously considered to be relatively benign with a low associated complication rate. However, a high incidence of medial subluxation of the patella was recently reported in patients with persistent symptoms after lateral retinacular release. Because the use of physical examination criteria may not always be sufficient to assess patellar alignment, 40 patients (43 knees) were evaluated by the newly developed technique of kinematic magnetic resonance imaging of the patellofemoral joint. One (2%) patellofemoral joint had normal patellar alignment, 10 (23%) had lateral subluxation of the patella, 1 (2%) had excessive lateral pressure syndrome, 27 (63%) had medial subluxation of the patella, and 4 (9%) had lateral-to-medial subluxation of the patella. Seventeen of 40 patients (43%) with unilateral arthroscopic lateral retinacular releases had medially subluxated patellae on the unoperated joints. Because patellar malalignment commonly affects bilateral joints, medial subluxation of the patella may have been present before the lateral retinacular release but was not recognized in these patients.

Adult↗

Late results of transfer of the tibial tubercle for recurrent dislocation of the patella.

The authors wished to determine the late results of the Hauser operation, with special reference to the development of osteoarthritis. Predisposing factors associated with recurrent dislocation of the patella were also investigated. Thirty-five patients with forty-four surgically treated knees attended for review, ten to twenty-five (average sixteen) years after operation. Two patients had subsequently undergone excision of the patella. Ten patients gave a family history of recurrent dislocation of the patella and seven patients showed generalised joint laxity. Pain was present in eight knees before operation and was present in thirty-three knees (75 per cent) at the time of review. Patella crepitus was present in thirty-seven out of forty-two knees (88 per cent) at review. Osteoarthritis was present in thirty out of forty-two knees (70 per cent). The incidence increases with time since operation and the present age of the patient. It is concluded that the Hauser operation prevents further dislocation but does not prevent the development of osteoarthritis. It is possible that a simple soft-tissue operation which effectively prevents dislocation might achieve the same results.

Adolescent↗

Rotation of the tibia in the normal and ligament-deficient knee. A study using biplanar photography.

The difference between physiological tibial rotation and rotatory instability of the knee, particularly the 'pivot shift' phenomenon, was investigated by analysing knee movements under both rotatory and valgus torques using 29 fresh cadaveric knees. The knee movements were measured in three dimensions using biplanar photography, when all ligaments were intact, and then after the ligaments were sequentially sectioned. The axis of the physiological tibial rotation was shown to be located about the centre of the tibial plateaux, while that of the pivot shift is located about the medial collateral ligament (MCL). When the anterior cruciate ligament (ACL) was sectioned, little or no significant change in physiological tibial rotation was observed under rotary torques, while a significant rotatory instability, including the 'pivot shift' phenomenon, was observed under a valgus torque. It was thus concluded that the rotatory instability is not simply an increase in the magnitude of the physiological rotation of the tibia, but is an abnormal tibial rotation which occurs with a different mechanism.

Adult↗

The Porous-Coated Anatomic total knee experience. Special emphasis on complications and wear.

One hundred sixty knees in 141 patients with the Primary Porous-Coated Anatomic prosthesis (Howmedica, Rutherford, NJ) were evaluated after a follow-up period of 5.6 years (range, 1-10 years). One hundred six knees were in the latest follow-up evaluation, including clinical examination and a defined standing radiograph with a follow-up period of 6.3 years (range, 3-10 years). Survivorship analysis regarding the cumulative revision rate (including completion with a patellar component) was 0.88 at the 8-year and 0.84 at the 10-year follow-up examination. The clinical result was satisfying/good, with a mean Hospital for Special Surgery score of 83 (range, 39-97). Five percent had thinning greater than 30% of the tibial component. The wear was calculated to be 1.0 mm (range, 0-9 mm), including three revised tibial components with heavy wear. Excluding the revised cases, the wear was 0.7 mm.

Aged↗

Arthrodesis of the knee following failed total knee arthroplasty.

In forty-five patients, who had an arthrodesis because of failed total knee arthroplasty, the cause was infection in forty, instability in two, failure of the prosthesis in two, and loosening in one. The arthrodesis succeeded in twenty-nine (81%) of thirty-six patients who had had a minimally or partially constrained arthroplasty and in five (56%) of nine who had had a hinge-type prosthesis inserted. The reasons for failure were severe bone loss, persistent sepsis, and loss of bone apposition after manipulation. The technique of arthrodesis did not seem to influence the final result. External fixation most commonly had to be used because of the infections and the device was kept in place for an average of ten weeks, after which immobilization in a cast was used until the arthrodesis healed.

Adult↗

Clinical and roentgenological studies on malalignment disorders of the patello-femoral joint. Part I: Classification of patello-femoral alignments using dynamic sky-line view arthrography with special consideration of the mechanism of the malalignment disorders.

Dynamic sky-line view arthrography at 30, 60, and 90 flexion degrees was carried out on 1,242 knees of 621 cases who claimed trouble with at least one knee. The patient's age range was from 15 to 35 years. Alignment of the patello-femoral joint was classified into four groups; Grade I: The patello-femoral joint is congruent in all the three views. Grade II: The view taken at 30 degrees shows the joint space open in the medial facet but closed in the view at 60 degrees. Grade III: The medial interspace is open at 60 degrees but closed at 90 degrees. Grade IV: The medial joint space is open in all three views. Grade distribution of all cases studied was: Grade I, 62.1%; Grade II, 25.8%; Grade III, 6.7%; and Grade IV, 5.4%. Clinical disorders thus occur at high percentages in the groups of Grades III and IV. Based on this observation, the mechanism of the malalignment disorders of the patello-femoral joint is discussed.

Adolescent↗

[Postero-internal menisco-capsular disinsertions associated with chronic instabilities of the knee caused by rupture of the anterior cruciate ligament].

Posterior menisco-capsular tears of the medial compartment of the knee can be considered as a complication of rupture of the anterior cruciate ligament and the consequent medial instability. The lesion is more a capsular lesion than a true meniscal one and it is related to an excessive stress on the oblique fibres of the ligament of Hughston attached to the meniscus. The diagnosis is based on arthrography made with meticulous technique. The lesion must be differentiated from true meniscal tears because it can be sutured. One hundred and twenty five such lesions have been operated on and reviewed after a follow-up of an average of two years. The technique must be very precise to prevent any secondary lesion due to surgery and to avoid any plaster cast immobilisation. The results have been satisfactory in 69 p. 100. They should be improved with more accurate surgical technique and with more precise indications.

Arthroscopy↗

Experimental hyaline cartilage lesions: two-dimensional spin-echo versus three-dimensional gradient-echo MR imaging.

The value of magnetic resonance (MR) imaging, with two-dimensional (2D) spin-echo and FISP (fast imaging with steady-state precession) and FLASH (fast low-angle shot) three-dimensional (3D) gradient-echo sequences, for the detection of hyaline cartilage defects of the femoral condyle and the tibial plateau, was investigated in an animal model. In eight dogs, the anterior cruciate ligament was transected in one knee joint, resulting in rapid development of osteoarthritis with degeneration of the hyaline cartilage. At autopsy, 24 cartilage lesions were found, which were classified into four grades. The overall detection of cartilage lesions with MR imaging was poor. Only five of the 24 lesions were visible on 2D spin-echo images, while 11 of 24 were visible on 3D FISP images and 15 of 24 were seen on 3D FLASH images. The best results were obtained in advanced stages of cartilage degeneration, involving ulceration and complete abrasion of the cartilage layer. Signal loss or signal intensity increase in the cartilage layer was seen inconsistently in grades 3 and 4 degeneration. In this animal model, 2D spin-echo imaging was inadequate for the diagnosis of hyaline cartilage lesions, while 3D gradient-echo imaging permitted satisfactory diagnosis in only grade 4 cartilage disease.

Animals↗

[Dysplasia of the femoral trochlea].

Dysplasia of the trochlea was studied on a strict profile image of the knee. 1305 radiographs were analysed corresponding to several patello-femoral conditions (major and subjective patello-femoral osteoarthritis) and to control subjects. Two criteria are defined: the depth and the eminence of the trochlea. The depth was often minimal in instabilities that give a radiological characteristic image of intersection between the trochlear end line and the lateral condyle. This picture had a great diagnostic value for patellar instability. The eminence represented the owerhang of the trochlear end line in relation to the anterior cortex of the femur. By measuring it, it was possible to establish a statistically significant variability of the degree of instability on one hand, between instabilities, patellar syndromes and controles on the other hand. The intersection sign and the trochlear eminence in isolated patello-femoral osteoarthritis allows the direct filiation between dysplasia of the trochlea and osteoarthritis to be confirmed. Taking into account the size of the eminence, the hollowing out type trochleoplasties appears more fiable than raising of the lateral edge.

Bone Diseases, Developmental↗

Recurrent dislocations and subluxations of the patella.

Seventy-four patients with patellar dislocations and subluxations were treated with a procedure described by Trillat. The Trillat method consists of stepwise correction of predisposing anatomic abnormalities including lateral retinacular release, patellar tubercle transfer, and advancement of the vastus medialis, if necessary. The follow-up period in 42 knees was from two to nine years with an average of 4.2 years. The results were excellent in six knees, good in 28 knees, fair in five knees, and poor in three knees. Thorough intraarticular examination is essential. If significant patellofemoral arthritis is present, a Maquet procedure should be performed.

Adolescent↗

A modified Hauser procedure for recurrent dislocation of the patella. A long-term follow-up study with special reference to osteoarthritis.

A modified Hauser operation was used for the treatment of recurrent dislocation of the patella. Thirty-seven patients (40 knees) were traced for the purpose of long-term follow-up with regard to subjective and objective results and the degree of osteoarthritis in the patellofemoral joint. The mean follow-up time was 18 years. Only 12% of the patients had objectively satisfactory results, but 48% were satisfied with their operation. There was no correlation between the opinion of the patients and the objective findings. Dislocation recurred in 20% of the knees. More than two-thirds of the patients had some degree of osteoarthritis, and a poor result was always combined with osteoarthritis. The incidence of osteoarthritis increased with the time of follow-up and the age of the patient, but it was also found in younger patients. It seems that distal realignment of the patella enhances the development of osteoarthritis.

Adolescent↗

Acute dislocation of the patella. A correlative pathoanatomic study.

The objective of our study was to elucidate the characteristic pathoanatomy associated with patellar dislocation and report the preliminary results of early surgical repair. Twenty-three patients with documented patellar dislocation had standard radiographs and a magnetic resonance imaging scan. Intraarticular lesions were evaluated and treated arthroscopically followed by an open exploration of the medial aspect of the knee in 16 patients. Twelve patients were observed for a minimum of 2 years after surgical repair (average, 34 months). Eleven patients returned for a follow-up examination. Magnetic resonance imaging revealed effusion (100%), tears of the femoral insertion of the medial patellofemoral ligament (87%), increased signal in the vastus medialis muscle (78%), and lateral femoral condyle (87%) and medial patellar (30%) bone bruises. Arthroscopic examination revealed osteochondral lesions involving the patella and the lateral femoral condyle in 68% of cases. Open surgical exploration revealed tears of the medial patellofemoral ligament off the femur in 15 of 16 patients (94%). After medial patellofemoral ligament repair, none of the patients experienced recurrent dislocation. Overall 58% of the results were considered to be good or excellent and 42% were fair. Fifty-eight percent of the group returned to their previous sport with no or minor limitations.

Acute Disease↗

Inter- and intraobserver reproducibility in radiographic diagnosis and classification of femoral trochlear dysplasia.

Dejour's radiographic criteria are commonly used to diagnose and assess femoral trochlear dysplasia in case of patello-femoral instability. The aim of this study was to establish the intra- and interobserver reliability of these radiographic criteria. Sixty-eight lateral knee radiographs were examined independently by 7 observers (2 juniors, 5 seniors) to assess interobserver agreement, and the 2 juniors repeated the observations to test intraobserver agreement. These 68 true lateral views were harvested from clinical records of 64 patients who underwent a trochleoplasty because of patellofemoral instability. To evaluate the agreement on analytic data (morphologic type of trochlea) we used the kappa statistical method, and to evaluate the agreement on numerical data (depth and prominence of the trochlear groove) we used interclass correlation analysis. The "crossing sign" (between the trochlear groove and the anterior aspect of both condyles) was reliable since the probability of rating as normal a pathologic trochlea was only 3.1% (0 to 8.8%). In classifying trochlear morphology interobserver agreement was slight (kappa = 0.17) and intraobserver agreement was fair (kappa = 0.3). On the other hand, the measurements of the depth and prominence of the trochlear groove were more reliable since the interclass coefficients between observers were 0.62 and 0.38 respectively. The most frequent interobserver error was related to misdiagnosis of type II. To clarify Dejour's criteria we propose a diagnosis of type II only when 5 mm or more are measured between the intersections with the medial and lateral femoral condyles. We recommend the use of the prominence of the trochlear groove to evaluate the grade of bony trochlear dysplasia.

Adult↗