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Modified Elmslie-Trillat procedure for instability of the patella.

The purpose of this study was to determine whether or not the modified medial transfer of the ligamentum patellae in case of objective instability of the patella is an adequate therapy and if it is possible to improve the patellar congruence angle by this method. Between October 1987 and April 1993, 41 operations were performed in 37 patients with medialization of the medial third of the ligamentum patellae with the corresponding part of the tibial tubercule. Four patients needed a bilateral operation; the two interventions were not performed at the same time. Thirty-six operated knees (88%) were examined at a median clinical and radiological follow-up of 62.8 months (+/- 15.8 SD). For evaluation, the objective and subjective Turba score was used, and pre- and postoperative X-rays were compared. The patients' average age at the time of intervention was 23.2 years (+/- 7 years SD). The operation was performed 39 times for recurrent dislocation or subluxation, for patella alta with cartilage tissue damage, and for first time traumatic dislocation. The only postoperative complication was a temporary peroneal paresis. There were no redislocations seen at the follow-up. One patient with repeated subluxations underwent an additional lateral release combined with a repair of the medial retinaculum. In all other cases, the Turba score showed good or excellent results (subjective 1.9; objective 0.8), the patellar congruence angle was significantly improved (P < 0.001), and there were no medial subluxations. We conclude that the transfer of the medial third of the ligamentum patellae for objective instability of the patella is a minimally invasive and adequate technique to improve significantly a pathological patellar congruence angle.

Adolescent↗

[The diagnosis and treatment of patellar instabilities].

In connection with 23 different patellar instabilities, the author makes some diagnostical and treatment consideration. The patients were between 18 and 40 years old, 13 women and 10 men. From the clinical point of view there were found 2 simple instabilities, 3 external dislocations, 6 permanent dislocations, 9 relapsed dislocations and 3 of them were habitual. The results in first time were good and excellent in 90 percent. It was a single relapse and by 4 of the patients which have been in watch for five years it was found arthrosis without major functional signs.

Adolescent↗

[Mid-term results of Wallaby I posterior cruciate retaining total knee arthroplasty: a prospective study of the first 425 cases].

PURPOSE OF THE STUDY: Posterior Wallaby I is a fixed polyethylene tibial plateau prosthesis enabling preservation of the posterior cruciate ligament (PCL). Its asymmetrical and divergent femoral condyles articulate with also asymmetrical tibial plateaus. The purpose of this prospective study was to analyze outcome of the first 425 Wallaby I prosthesis of the Guepar group implanted for first-intention treatment. MATERIALS AND METHODS: These 425 prostheses were implanted from December 1992 to February 1995 by senior and junior surgeons. Mean patient age at implantation was 70.5 years. 91% had primary or secondary osteoarthritis and only 8.9% had inflammatory rheumatoid disease. The mean preoperative IKS score was 25.34 points and the IKS function score was 29.04. 10.35% of knees were aligned normally (mechanical axis between 2 degrees varus and 3 degrees valgus) according to the IKS criteria (Ewald), 24% presented valgus > or = 4 degrees and 65.6% varus > or = 3 degrees. All tibial and patellar components (except one) were cemented, 5.8% of the femoral pieces were inserted without cement. All but 11 patellae were resurfaced. Clinical outcome was assessed with the IKS score and radiological outcome with the IKS criteria. The patella was considered to be tilted when the alpha angle was > 5 degrees and dislocated when the AA' distance was > 5 mm. The chi-square test was used for comparison of quantitative variables (significance set at 0.05). RESULTS: Early postoperative complications were rare: two infections cured with debridement-lavage and antibiotics without removal of the prosthesis, one peronal nerve palsy which regressed partially, ten late unions without clinical consequence (particularly in the inflammatory rheumatoid patients). Twenty-six prostheses were followed less than one year (eight patients died and eighteen were lost to follow-up) and 84 less than five years (27 patients died and 57 lost to follow-up before five years). 315 prostheses were followed for more than five years (5-9 years) with a mean follow-up of 6.3 years. Among the 399 prostheses followed for one year or more, we noted: four infections including three requiring change of the prosthesis (one cured by arthroscopic lavage), two aseptic loosenings which were revised (one global one tibial), one tibial loosening and three patellar loosenings which were not revised, and two femoral ossifications limiting joint motion but improved by arthrolysis and resection of the ossifications. Three patients experienced anterior pain requiring secondary patellar resurfacing in two and section of the lateral patellar wing in one. Ninteen patellar fractures (4.7%) were noted, including 17 with no significant functional impact which were not revised. The mean IKS knee score among prostheses followed for five years was 90.5 points, with mean motion 110.5 degrees. Mean IKS function score was 61.63 points. 72.9% of the knees were aligned, 22.2% in varus and 4.9% in valgus. The mechanical axis of 94.3% of the knees was between 5 degrees varus and 5 degrees valgus. Prosthesis survival at eight years (Kaplan-Meier method) was 97.7% considering all reasons for prosthesis removal and 98.5% for removal for aseptic loosening. CONCLUSION: This prospective multicentric study demonstrated that the results obtained with the Wallaby I prosthesis are as good as those obtained with other prostheses sparing the PCL and published in the literature. Preservation of the PCL enables better knee stability, correct motion (110.5 degrees in our series) with almost no radiological wear of the tibial polyethylene at eight years. The only worrisome complication is patellar fracture.

Adult↗

Subluxation of the patella: evaluation of patellar articular cartilage with MR imaging.

In patients with subluxation of the patella, injury of the patellar articular cartilage is frequently observed, and correct evaluation of this cartilage injury is extremely important for the management of these patients. Magnetic Resonance (MR) studies were performed on 102 patellofemoral (PF) joints of 51 patients with subluxation of the patella and 20 PF joints of 10 healthy volunteers. In 77 of the 102 PF joints with subluxation, arthroscopy and/or operation were performed. MR images were obtained with spin-echo and FLASH sequences, and para-axial images were obtained. We retrospectively analysed the MR findings of the 77 joints with special attention to the surface and thickness of the cartilage, and classified them into four grades. These MR grades were compared with the grades on arthroscopy, and the following results were obtained: MR grade 0, normal cartilage (n = 27, sensitivity 90.9%, specificity 74.2%); MR grade 1, thickening of the cartilage (n = 24, sensitivity 50%, specificity 89.1%); MR grade 2, surface irregularity of the cartilage (n = 20, sensitivity 85%, specificity 94.7%); MR grade 3, loss of the cartilage (n = 6, sensitivity 100%, specificity 100%). Although the early changes observed by arthroscopy were underestimated from the MR images, MR imaging proved to be extremely useful for evaluating moderately or advanced patellar cartilage injury.

Adolescent↗

Progressive subluxation and polyethylene wear in total knee replacements with flat articular surfaces.

One hundred eighty-six Microloc tricompartmental, cruciate-sparing, primary total knee replacements in 136 patients were performed between 1983 and 1987. Femoral components were made of cobalt-chrome-molybdenum alloy. The tibial component baseplates were made of titanium-aluminum-vanadium alloy. The baseplates were made with three small porous-coated pegs for fixation with or without cement, or with a central stem for fixation with cement. The polyethylene was affixed to the baseplate by a mechanical locking mechanism that was nonmodular. The articular surfaces of both components were flat mediolaterally and anteroposteriorly. The patellar components were dome shaped and metal backed with titanium-aluminum alloy. Seventy-three percent of the femoral components, 26% of the tibial components, and 48% of the patellar components were inserted without bone cement. The average time to maximum follow-up examination was 6.1 years (range, four to nine years). Of implants that had not been revised, 84.4% had good or excellent results (using the Hospital for Special Surgery scoring system) at final follow-up examination. The average range of motion of functioning implants at final follow-up examination was 108 degrees. Revisions for failure only of the metal-backed patellar component were performed in 22 knees (11.8%). Forty knees (21.5%) required revision for failure of the femoral-tibial articulation. Reasons for failure in this group included: polyethylene wear (57.5%); loosening (15.0%); tibial tray fracture (10.0%); sepsis (12.5%); and dislocation or ligament laxity (5.0%). An additional 15 functioning knees (8.1%) have radiographic evidence of progressive femoral-tibial subluxation. Future failure of these devices is considered likely. Polyethylene wear requiring revision was not statistically associated with patient age, gender, preoperative diagnosis, height, weight, or component size. Polyethylene failure leading to revision was related to the radiographic appearance of femoral-tibial component subluxation. This subluxation was most likely to occur after five years of component implantation. The development of progressive femoral-tibial subluxation was statistically associated with postoperative extremity malalignment, excessive varus positioning of the tibial component, bone grafting of the tibial plateau, the use of the small-pegged tibial component, and the use of this component without cement. Polyethylene wear associated with progressive femoral-tibial subluxation occurred at the periphery of the tibial plateau and along the raised portion of the tibial spine. The metal baseplate at the edge of the plateau was frequently exposed and worn. Bone lysis associated with the presence of polyethylene, metal, and cement debris was frequently observed.

Adult↗

[MRI evaluation of the patellar articular cartilage in patients with subluxation of the patella].

In patients with subluxation of the patella, injury of the patellar articular cartilage is frequently observed and correct evaluation is important to manage these patients. We examined 11 patients with subluxation of the patella and five normal volunteers. In 12 patellofemoral joints of seven patients with subluxation of the patella, the abnormalities observed on MRI were compared with those on arthroscopy and/or at operation. MRI was performed with a Magnetom 1.5 T (Siemens) using the round surface coil. Pulse sequences were SE (TR 400 ms/TE 19 ms), FLASH (TR 320 ms/TE 15 ms FA 90 degrees and 40 degrees), and SE (TR 2000 ms/TE 26, 70 ms). We analysed MR findings of the 12 abnormal joints and 10 normal joints according to the following classification of abnormalities observed on arthroscopy. (1) normal appearance (n = 3 joints), (2) softening and fibrillation (n = 6), (3) fragmentation (n = 3), and (4) erosion to bone (n = 0). In only one of the six cases with softening and fibrillation observed on arthroscopy, MRI could visualize the thickening of patellar articular cartilage, but in all three cases with fragmentation observed on arthroscopy, MRI could visualize the thin inhomogenous cartilage with irregular surface. The combination of SE (TR 400 ms/TE 19 ms) and FLASH (TR 320 ms/TE 15 ms FA 90 degrees) are extremely effective pulse sequence to detect the abnormalities of patellar articular cartilage. We conclude that MRI is a useful noninvasive method of detecting advanced changes in patellar articular cartilage.

Adolescent↗

The value of computed tomography for the diagnosis of recurrent patellar subluxation in adolescents.

OBJECTIVE: To determine if computed tomography of the patellofemoral joint has any advantage over standard radiologic techniques in the evaluation of recurrent patellar subluxation. DESIGN: A case series. SETTING: A tertiary children's hospital out-patient clinic. PARTICIPANTS: Forty consecutive adolescents with a clinical diagnosis of recurrent patellar subluxation (study group) and 14 volunteers with normal knees (control group). INTERVENTIONS: A standardized radiologic protocol, including axial views of the patella at 30 degrees of knee flexion, with and without external torsion of the tibia, and computed tomography (CT) of the patella at 15 degrees of knee flexion. MAIN OUTCOME MEASURES: The lateral patellofemoral angle on the axial views and on the CT scan and patellar centralization on the CT scan. RESULTS: In the control group, no radiologic evidence of recurrent patellar subluxation was found. In the study group, an abnormal lateral patellofemoral angle was found in 25% of axial views; this rate increased to 42% with external rotation and 86% on the CT scan. Patellar centralization was abnormal in 79% of cases. CONCLUSIONS: CT of the patellofemoral joint is more sensitive than standard radiographs for the diagnosis of recurrent patellar subluxation. The use of CT is recommended when standard radiographs appear normal.

Adolescent↗

The patello-femoral joint--a critical appraisal of its geometric assessment utilizing conventional axial radiography and computed arthro-tomography.

In the quest for treatable causes of anterior knee pain, plain film skyline views of the patello-femoral joint are requested, often in 30 degrees, 60 degrees and 90 degrees of flexion, to assess the functional relationships of the joint. Patello-femoral malalignment predisposes to recurrent subluxation and dislocation, articular cartilage damage and premature degenerative change. The aim of this study is to evaluate critically, by comparative assessment, the information provided by skyline views and axial computed arthro-tomography (CTA). Measurements of the patello-femoral angle (assesses patellar tilt), the congruence angle (assesses patellar lateralization) and the trochlear depth were made on Merchant's skyline views and on axial CTA on each of 50 symptomatic knees. Results are presented in graphic form with visual examples indicating a poor correlation between the two imaging methods. We conclude that skyline views are inaccurate and unsuitable primarily because they cannot be obtained in less than 30 degrees of flexion. We suggest that skyline views have no role to play in screening for maltracking as even florid examples must be missed, and would strongly urge that no surgery be performed on their basis alone as this would result in inappropriate operations. Although computed tomography is the preferred mode of assessing patello-femoral geometry, difficulties are still encountered and the ways of circumventing them are discussed.

Femur↗

Arthroscopic reduction and fixation of osteochondral fracture of the patellar ridge.

A method of arthroscopic reduction and anterograde fixation of osteochondral fracture of the patella ridge is described. This type of fracture was previously treated through arthrotomy. An arthroscopic approach is possible using manipulation of the patella in a loosened medial retinaculum. This method was used in a 14-year-old patient with an osteochondral fracture following the dislocation of the patella.

Absorbable Implants↗

Primary repair of the cruciate and collateral ligaments after traumatic dislocation of the knee.

The management of traumatic dislocation of the knee in 40 patients (41 knees) with a mean age of 26.3 years is described. They were treated by primary repair and reconstruction with autologous grafting of the anterior (ACL) and posterior cruciate ligaments (PCL) and repair injuries to the collateral ligament and soft-tissue. The ACL and PCL were reconstructed using the patellar tendon and the gracilis and semitendinosus tendons, respectively. Early mobilisation using a continuous-passive-movement machine and active exercises was started on the second day after operation. At a mean follow-up of 39 months no patient reported 'giving way' and all except one had good range of movement. Of the 41 knees, 21 were rated as excellent, 15 good, four fair and one poor. Early reconstruction of the cruciate ligaments and primary repair of the collateral ligaments followed by an aggressive rehabilitation programme are recommended for these young, active patients.

Adolescent↗

Results of treatment of displaced patellar fractures by partial patellectomy.

The results of partial patellectomy as a treatment for displaced patellar fractures were assessed retrospectively with use of clinical, radiographic, and isokinetic strength-testing criteria. Forty patients who had been followed for an average of 8.4 years were studied. In the extremity that had been operated on, the mean active range of motion was 94 per cent, the circumference of the thigh was 100 per cent, and the strength of the quadriceps was 85 per cent of these measurements in the contralateral extremity. The over-all result was rated as excellent in twenty patients, good in eleven, fair in six, and poor in three. There was a significant statistical correlation between the type of fracture and the outcome. The results of this study indicate that partial patellectomy can be an effective treatment for selected patellar fractures.

Adult↗

A comparison of four models of total knee-replacement prostheses.

Twenty-nine knees with unicondylar, sixty-four with duocondylar, fifty with Guepar, and fifty with geometric prostheses were studied. The follow-up ranged from two to three and one-half years. The unicondylar prosthesis was used in the mildest cases and gave the least complications, but the quality of results was not superior to that achieved with the other prostheses. The duocondylar model was best suited for knees with rheumatoid arthritis and mild deformity. The geometric prosthesis was the best condylar prosthesis for osteoarthritis with moderate to severe deformity, but gave the worst results in knees with rheumatoid arthritis. The Guepar prosthesis was used in the worst knees and gave the best results, but it had the highest infection rate and was the most difficult to salvage. A radiolucency was observed in about 60 per cent of the condylar replacements around the tibial component and in 45 per cent of the Geupar replacements around the femoral component. The significance of this cannot yet be determined but it suggest that the fixation may not be ideal. In all types, residual pain was most frequently attributed to the patellar compartment. Patellectomy was not a solution.

Aged↗

[Recurrent dislocation of the patella--arthroscopic therapy].

PURPOSE OF THE STUDY: The authors present results of the surgical treatment of the recurring patella dislocation. They use the surgical technique of medial percutaneous raphe by absorbable PDS suture and lateral release with arthroscopis assistance. MATERIAL: The operation was performed for recurring dislocation in 19 cases in 16 patients. Three patients underwent a surgery on both knees. The average age of patients was 22 years (range, 14-29 years). The average period after the surgery was 22 months (range, 12-45 months). Minimal number of dislocations prior to operation was 3, maximal more than 20. METHOD: The surgical technique consists in medial raphe by percutaneously inserted absorbable PDS suture with arthroscopic assistance and in performing a lateral release in the "closed manner" under the check of the arthroscope. After-care consists in the application of a rigid orthesis which is starting from the first postoperative day removed for physiotherapy by CPM. After two weeks a hinged orthesis is used with a gradual increase of the range of motion. After 6 weeks the patient starts full weightbearing without any fixation. The authors evaluated the results of the operation after Bentley. They also followed the duration of turniquet of the operated on limb, the duration of hospitalization and the period necessary for the achievement of the full range of motion. Radiograph was used for the determination of the shape of patella after Baumgartl and Wiberg, the angle of the femoral sulcus, the height of patella after the Insall-Salvati index and lateral shift of patella. Arthroscopic examination focused on the evaluation of the patellar and femoral chondromalacy and its classification after Outerbridge. Clinically, Q angle was measured, the axis of the limb, anxiosity test was made and the presence of crepitation was checked. RESULTS: Ninety per cent of the patients evaluated the condition after the surgery as very good or good, twice as poor. In one patient there occurred one recurrence of dislocation after the surgery. In the second patient after the surgery pain aggravated in connection with a severe degenerative damage of the femoropatellar joint. Neither avascular necrosis of the patella nor any more extensive bleeding was encountered. There was no infectious complication in the group of patients. Chondral lesion was recorded in 80% of patients. The degree of the damage increased with the number of dislocations. A frequent complication was a recurring knee effusion with the necessity of its evacuation. The relation between the number of dislocations and the final outcome of the surgery was proved. No patient with the number of dislocations 10 and more was evaluated as excellent. DISCUSSION: AS release and medial raphe is a surgical technique which brings very good and good results in a high number of patients. Independently performed raphe or release do not have comparable good results in the therapy of recurring dislocation. The authors' results do not differ from data in specialised literature. CONCLUSION: Arthroscopically performed lateral release and medial raphe by percutaneously inserted suture and with AS assistance has a number of unquestionable benefits. The performance is associated with only minimum complications. It reduces the duration of hospitalization, immobilization of the limb, duration of physiotherapy as well as the total duration of the incapacity to work. The cosmetic result is good. It is possible to operate on also on young patients prior to the final ossification in the area of the tibial tubercle. A prerequisite of a good result is an accurate performance of the operation and subsequent physical therapy. Contraindications include marked degenerative changes in the femoropatellar joint, instability of the knee, patella dislocation in TKR. Q angle exceeding 30 degrees and valgus deformity of the limb exceeding 15 degrees. A high number of dislocations and the resulting more severe damage to the cartilage reduce the potential for achieving excellent results.

Adolescent↗

Patellofemoral joint motion: evaluation by ultrafast computed tomography.

Patellofemoral maltracking is a recognized cause of peripatellar pain. Measurements of the patellofemoral relationships during active motion are not available, and clinicians currently rely on observation, palpation, and static radiographic images to evaluate the symptomatic patient. Ultrafast computed tomography (ultrafast CT) offers objective observations of the dynamic influences of muscle contraction on the patellofemoral joint as the knee is actively moved through a range of motion from 90 degrees flexion to full extension. This study reports our initial observations and establishes a range of normal values so that patients with a clinical suspicion of patellar maltracking may be evaluated.

Adult↗

Surgical treatment of patellar instability: indications and results.

The purpose of this study was to evaluate a consecutive series of 465 patients with patellar subluxation. Both knees were involved in some patients. Therefore, 557 knees were studied. The average age was 24 years. Specific symptoms and signs were reviewed. Instability, swelling, and patella alta were more common in the group requiring surgery. All patients were treated conservatively with specific exercises initially. Failure of this conservative treatment to significantly improve the symptoms, inability to do the activities of daily living, or expected associated pathology were indications for surgery. Surgery was required in 139 patients (27%). Some patients had surgery on both knees. Therefore 149 knees were repaired. The surgical technique consisted of an extensor mechanism realignment. This consisted of release of the lateral patellofemoral ligaments, advancement of the vastus medialis obliquus muscle and, in some cases, transfer of the tibial tubercle. Arthrotomy was done in all cases. Results were evaluated in terms of pain, function, and patellar instability. Signs evaluated preoperatively and postoperatively were tenderness of the retinaculum or bone, patellar mobility, effusion, muscle atrophy, and tone. Range of motion was also evaluated. The average followup lasted three years.

Athletic Injuries↗

The correlation between arthroscopic findings and the patellofemoral pain syndrome.

For this study, 1,784 arthroscopies were analysed. Abnormalities of the patellofemoral joint consisting of patellar malalignment and/or patellar chondral damage were present in 175 (10%). Two types of lesion were identified, distinguished by the alignment of the patellofemoral joint, namely, subluxation with or without chondral damage (group I) and chondral damage without subluxation (group II). Group I (mean age, 25 years) included a greater proportion of women than group II; in 72%, the predominant clinical feature was patellofemoral pain syndrome (PFPS). Group II (mean age, 43 years) included fewer women; PFPS was found in only 32%, but in 82% there were signs of degenerative joint disease, which could explain the symptoms. Patellar subluxation was correlated to the PFPS, whereas chondral damage alone was not.

Adult↗