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At least 865 records · Page 48Linked to original sources
PubMed2005

The multiple-ligament injured knee: evaluation, treatment, and results.

The multiple-ligament injured knee is a complex problem in orthopaedic surgery. Most dislocated knees involve tears of the anterior and posterior cruciate ligaments (ACL/PCL) and at least 1 collateral ligament complex. Careful assessment of the extremity vascular status is essential because of the possibility of arterial and/or venous compromise. These complex injuries require a systematic approach to evaluation and treatment. Physical examination and imaging studies enable the surgeon to make a correct diagnosis and to formulate a treatment plan. Arthroscopically assisted combined ACL/PCL reconstruction is a reproducible procedure. Knee stability is improved postoperatively when evaluated using knee ligament rating scales, arthrometer testing, and stress radiographic analysis. Acute medial collateral ligament (MCL) tears, when combined with ACL/PCL tears, may in certain cases be treated with bracing. Posterolateral corner injuries combined with ACL/PCL tears are best treated with primary repair as indicated, combined with reconstruction using a post of strong autograft (split biceps tendon, biceps tendon, semitendinosus) or allograft (Achilles tendon, bone-patellar tendon-bone) tissue. Surgical timing depends on the ligaments injured, the vascular status of the extremity, reduction stability, and the overall health of the patient. We prefer to use allograft tissue for reconstruction in these cases because of the strength of these large grafts and the absence of donor site morbidity.

Achilles Tendon↗
PubMed1998

[Resilience of tibial transplant fixation for replacement of the anterior cruciate ligament. Interference screws vs. staples].

The endoscopic single incision technique for ACL reconstruction with a femoral half-tunnel may lead to a graft/tunnel mismatch and subsequent protrusion of the block from the tibial tunnel. The typical tibial fixation with an interference screw is not possible in these cases. Fixation with staples in a bony groove inferior to the tunnel outlet can be used as an alternative technique. Current literature does not provide biomechanical data of both fixation techniques in a human model. This study was performed to evaluate primary biomechanical parameters of this technique compared to a standard interference screw fixation of the block. 55 fresh-frozen human cadaver knee joints of a younger age (mean age: 44 years) were used. Grafts were harvested from the patellar tendon midportion with bone blocks of 25 mm length and 9 mm width. A 10 mm tibial tunnel was drilled from the anteromedial cortex to the center of the tibial insertion of the ACL. 3 different sizes of interference screws (7 x 30, 9 x 20 and 9 x 30 mm) were chosen as a standard control procedure (n = 40). For tibial bone-block fixation the graft was placed through the tunnel, the screw was then inserted on the cancellous or the cortical surface respectively. 15 knees were used for staple fixation. A groove was created inferior to the tunnel outlet with a chisel. The bone block was fixed in this groove with 2 barbed stainless steel staples. Tensile testing in both of the groups was carried out under axial load parallel to the tibial tunnel in a Zwick-testing-machine with a velocity of 1 mm/sec. Dislocation of the graft and stiffness were calculated at 175 N load. Maximum load to failure using interference screws varied between 506 and 758 N. Load to failure using staples was 588 N. Dislocation of the graft ranged between 3.6 and 4.7 mm for interference screw fixation and was 4.2 mm for staples. With both fixation techniques, the recorded failure loads were sufficient to withstand the graft loads which are to be expected during the rehabilitation period. Staple fixation of the bone block outside of the tunnel resulted in fixation strength comparable to interference screw fixation.

Adult↗
PubMedDate not supplied

The torsion angle of the patellar tendon. A new CT parameter used for classification and treatment planning in femoropatellar syndrome.

The authors report a study conducted on 107 CT scans taken between January and December 2001 in 76 patients affected with femoropatellar pain, that did not benefit from physiotherapy. It is the purpose of this study to present a new CT scan parameter denominated torsion angle of the patellar tendon (TAPT) and to define an algorithm of treatment for this complex pathology based on the changes revealed by CT scan according to the Lyonese protocol. CT scan based on the Lyonese protocol provides an explanation of the symptoms and the objectivity via traditional parameters in 59.63% of patients. Thanks to the introduction of this new parameter (TAPT), which allows us to reveal the presence of an extrarotation of the proximal metaphysis of the tibia, the percentage of sensitivity with CT scan has been increased to 83.92%.

Adolescent↗
PubMed1986

Radiographic assessment in patellar instability and chondromalacia patellae.

Minor degrees of malalignment of the patella and anatomical abnormalities including a flattened sulcus angle and an increased ratio between patellar tendon length and patellar length (PT:P) have been suggested as predisposing factors in the causation of chondromalacia patellae, as well as patellar instability. In order to confirm or refute this hypothesis a prospective study has been performed comparing the congruence and sulcus angles and the PT:P ratio in a group of 35 patients with chondromalacia confirmed by arthroscopy and a group of 33 patients with instability, with those of a group of 50 knees in normal volunteers. While there was a statistically significant correlation between an increased sulcus and congruence angle and a high-riding patella in patients with instability, no correlation could be identified in patients with idiopathic chondromalacia.

Adolescent↗
PubMed1989

Alignment of the extensor apparatus of the knee by alar and tuberosity transposition in recurrent subluxation of the patella and in external patellar hypertension syndrome.

In consideration of the multiple anatomical structures involved in recurrent subluxation of the patella and in external patellar hypertension syndrome, the authors propose an operation which allows for complete realignment of the extensor apparatus by transposition of the anterior tibial tuberosity, division of the external alar ligament, tightening of the internal alar ligament, and correction of the muscular insertions. In particular, removal of a capsulofascial band medially and its reimplantation into the external incision is proposed, thus avoiding the formation of retractive scar tissue. The long-term results, which were overall satisfactory, confirm the effectiveness of the operation proposed.

Adolescent↗
PubMed1997

[Clinical experiences with the therapy for patella luxation of small animals using sulcoplasty and lateral and cranial relocation of the tuberositas tibiae].

Twenty cases with patellar luxation in dogs and cats, in which a sulcoplasty and cranialisation of the tuberositas tibiae were performed, were investigated and reviewed retrospectively. Twelve knees were available for follow-up after a mean period of 15 months. Clinical scoring of patients showed eight with no lameness, three with an occasional weightbearing lameness, and one with a frequent weightbearing lameness. The patella was stable and could not be luxated in ten out of twelve cases. Degenerative joint disease was slightly progressive in the postoperative period. It did not impair the outcome of the procedure.

Animals↗
PubMed2001

One-stage arthroscopically assisted anterior and posterior cruciate ligament reconstruction.

PURPOSE: To retrospectively evaluate 15 consecutive patients who underwent simultaneous isolated, arthroscopically assisted anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) reconstruction. TYPE OF STUDY: Case series. METHODS: A bone-patellar tendon-bone autograft was used as the PCL substitute and doubled hamstring tendons were used as the ACL graft. The IKDC evaluation form and the HSS, Lysholm, and Tegner clinical rating scales were used to make clinical evaluations. Anteroposterior translation was measured with the KT-2000 arthrometer and stress view radiography. RESULTS: At final IKDC evaluation, 3 patients (20%) were graded A, 7 (46.7%) were graded B, 3 (20%) were graded C, and 1 patient (6.7%) was graded D. One patient underwent revision surgery in another hospital for severe postoperative residual laxity. Two C-graded patients had an unsatisfactory outcome as a result of serious complications related to knee injuries. All patients with a grade A or B returned to sports activity. At stress view examination, mean posterior side-to-side translation measured at the lateral tibial plateau was 5.8 +/- 1.1 mm and the mean translation at the medial tibial plateau was 7.3 +/- 1.5 mm; the mean anterior dislocation was 3.3 +/- 0.4 mm. The preoperative HSS score rated an average of 32 +/- 9. Postoperatively, the average score reached was 89.6 +/- 8.3. The preoperative Lysholm score was 65.5 +/- 9.1 (range, 48 to 78) in patients with chronic lesions and at follow-up was 95.1 +/- 4.5 (range, 88 to 100). The average Tegner activity score decreased in patients with chronic lesions from 6.9 +/- 1.7 (range, 4 to 9) before injury to 5.5 +/- 1.6 (range, 2 to 9) at follow-up (P =.053 ). At follow-up, 7 patients (50%) returned to their preinjury level after surgery. CONCLUSIONS: These results show the effectiveness and safety of simultaneous arthroscopic reconstruction of both cruciate ligaments using autografts that can adequately restore satisfactory stability, even in the presence of minimal peripheral laxity (1 degrees or 2 degrees ). We conclude that the use of autografts can restore ligament function with good patient compliance and without significant surgical complications.

Adolescent↗
PubMed1996

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↗
PubMed1996

Modified Hauser operation for patellar instability. Immediate mobilization of 35 knees, a 5-8 year follow-up study.

We performed a follow-up examination of 35 knees with chronic patellar instability treated by a modified Hauser operation: medialization and distalization of the tibial tubercle without dorsal transfer, and fixation of the tubercle rigidly with 2 cortical screws. Cast immobilization was not used and the patients were allowed to mobilize the knee immediately. The follow-up period was 6 (5-8) years. 27 of 35 knees were excellent or good at follow-up, while 8 patients were more or less dissatisfied with the result. 5 knees had arthrosis at follow-up. No severe complications occurred, nor did the rate of minor complications differ from earlier reports.

Adolescent↗
PubMed1991

[An experimental study on early changes of articular cartilages in subluxated patella of rabbits].

The pathogenesis and clinical progress of chondromalacia patellae have not been well studied in experimental models. We, therefore, studied the patellar subluxation produced experimentally in rabbit knees. In this model, sequential changes of the patellar cartilage were followed by simple X-rays, CT, macroscopic, histologic and scanning electron microscopic examinations up to 32 weeks. Pathological changes extending from horizontal fissures in the middle to the deep layers of the patellar cartilage and thinning of the subchondral bone were found at about six weeks after operation. The early changes of chondromalacia patellae were mostly what is called the basal degeneration, which was presumably attributed to the shearing stress on the articular cartilage. The sequential changes were not very remarkable; none of the rabbits developed OA changes by thirty-two weeks after operation. From these findings, we have that the cartilaginous changes in chondromalacia patellae progress very slowly which probably result from the vigorous repair by the cartilage and also from the acquisition of adaptability on the patellofemoral joint.

Animals↗
PubMed2000

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↗
PubMed1995

Complications of extensor mechanism surgery for patellar malalignment.

This review focuses on the complications of extensor mechanism surgery for symptomatic patellar malalignment and ways to avoid those complications. We combined a review of new and referred patients who had complications resulting from extensor mechanism surgery with a review of selected literature specifically addressing similar complications. By studying the pathologic anatomy at the time of arthrotomy, it was possible in many cases to determine the causes of adverse outcomes with this type of surgery. The complications of extensor mechanism surgery can be avoided by performing a thorough preoperative evaluation, determining each component of the malalignment, tailoring the procedure to correct each patient's unique pathomechanics, and respecting the functional anatomy of the extensor mechanism.

Diagnostic Errors↗
PubMed2005

[Seven-year clinical experience with the SVL/Beznoska implant for total knee arthroplasty].

PURPOSE OF THE STUDY: The aim of the study was to evaluate our seven-year experience with the anatomic, non-constrained SVL/Beznoska implant for total knee replacement. MATERIAL: A total of 374 cemented total knee replacements, using the SVL/Beznoska implant, were evaluated in 333 patients treated at the First Orthopedic Clinic Charles University in Prague, during a seven-year period. In addition, a patellar replacement was used in five of these patients. Included in the evaluation were also eight non-cemented and hybrid SVL/Beznoska implants used 6 years ago. METHODS: The aim of the study was to evaluate the results in terms of implant function. Therefore, the longevity of implants was assessed by Kaplan-Meier's survival analysis. Another criterion was the flexion achieved. To be able to compare our clinical results involving the SVL/Beznoska implant with other, foreign types of implants, the patients were evaluated on the basis of the New Jersey Orthopaedics Hospital Knee Evaluation System. RESULTS: The Kaplan-Meier's survival score was evaluated. The mean maximum flexion achieved in the patients with SVL implants was 107 degrees . The evaluation by the New Jersey Orthopaedics Hospital Knee Evaluation System showed excellent outcomes in 269 (72 %) patients, good outcomes in 79 (21 %) patients, satisfactory in 19 (5 %) and poor in 7 (2 %) patients. There was no mechanical failure of the implant, such as break of an implant or dislocation of a PE component. Six infected implants and four aseptic loosenings were recorded. Three patients diagnosed with an infected total knee replacement had been treated for rheumatoid arthritis for a long time. One patient was on dialysis for renal insufficiency and one had erysipelas. DISCUSSION: The results of our group with the SVL/Beznoska implant were compared with those obtained from the group of 63 patients who underwent total knee arthroplasty with the LCS implant. In these patients, the mean maximum flexion achieved was 105 degrees , and the criteria of the Knee Evaluation System showed excellent outcomes in 81 %, good in 16 % and satisfactory in 3 % of the patients. No unsatisfactory outcome was recorded. Considering the fact that the LCS implant was used only in younger and active patients, the outcomes achieved with the SVL/Beznoska system can be regarded as very good. Of the six patients with infectious complications, three were treated with immunosuppressive therapy for rheumatoid arthritis, one was on dialysis for renal insufficiency and one experienced a flare-up of erysipelas. CONCLUSIONS: The most important outcome of the evaluation of 374 total knee replacements, using the SVL implant carried out at the First Orthopedic Department of the First Faculty of Medicine, Charles University, was the finding of a perfect function of all components in all patients treated. None of the complications occurring in our group was associated with the use of this implant.

Adult↗
PubMed1986

The evaluation of patellofemoral pain using computerized tomography. A preliminary study.

There are well-recognized limitations of conventional axial radiographs of the patellofemoral joint in assessing patients with peripatellar pain, particularly in the first 20 degrees of knee flexion. Computerized tomography (CT) was used, therefore, to evaluate 20 patients with persistent patellofemoral pain and ten asymptomatic volunteers. Multiple midpatellar images were obtained between zero degrees and 30 degrees -40 degrees (sometimes 40 degrees) of flexion, with and without maximal quadriceps contraction. Three distinct patterns of malalignment were identified. When compared to controls, 11 patients had lateralized patellae based on high-congruence angles in extension. With progressive flexion to 30 degrees, all but one reduced into the trochlea. This group was subdivided into those lateralized with or without associated patellar tilting. There were seven patients whose patellae progressively tilted between zero degrees and 30 degrees of flexion while remaining centered in the trochlea. Anatomic differences demonstrated by CT appear to be a factor in distinguishing these groups. Computerized tomography may be the optimal method of radiographically evaluating the patellofemoral joint. Patients have been identified with lateralized patellae in extension that subsequently become congruent by 30 degrees of flexion and therefore may not be appreciated on traditional radiographs. An awareness of different patterns of malalignment is a significant advantage of computerized tomography when planning selective surgical realignment for these patients.

Adolescent↗
PubMedDate not supplied

A retrospective evaluation of stifle osteoarthritis in dogs with bilateral medial patellar luxation and unilateral surgical repair.

The effects of surgical and nonsurgical therapy on the development of osteoarthritis were compared in 12 dogs with bilateral medial patellar luxation and unilateral surgical repair. Evaluations included severity of lameness and patellar luxation, ligamentous stability, range of motion, and radiographic evidence of osteoarthritis before surgery and at a mean of 33 months after surgery. Stifles without surgical treatment served as controls for the contralateral stifles with surgery. All stifles treated surgically had reduced patellofemoral joints, normal range of motion, and improved limb use. Osteoarthritis progressed significantly and comparably in both groups of stifles. Progression of osteoarthritis was not correlated with luxation grade, body weight, or interval from surgery to follow-up. Age at surgery was correlated positively with severity of osteoarthritis in the stifles treated surgically.

Animals↗
PubMed2006

Full arthroscopic inlay reconstruction of posterior cruciate ligament.

We report a full arthroscopic inlay reconstruction technique to avoid the morbidity of traditional open inlay procedure. With the transeptal approach a trough is created arthroscopically at the anatomical tibial insertion of the PCL, which must fit with the patellar bone block of a quadriceps tendon autograft. The bone plug is harvested with two nonabsorbable sutures, each end of which is passed through two holes from the cortical to the cancellous side. The graft is introduced into the knee joint from the posteromedial portal using two traction sutures passed previously through two transtibial tunnels exiting at the middle of the trough. Tibial graft fixation is achieved using the sutures knotted at the anterior aspect of the tibial cortex. Arthroscopic inlay procedure may be a rational surgical alternative because it reduces the crucial steps of an open inlay procedure, such as extensive exposure of the posterior capsule, the need of position change with risk of contamination, longer surgical time, and the risk of bone block fracture if an autograft is harvested. The arthroscopic procedure may also be performed also when hardware presence of previous surgery limits use of the open technique. We initially limited use of this technique to patients: (1) undergoing PCL revision surgery, (2) having hardware from previous tibial surgery, and (3) presenting a PCL lesion following posterior dislocation with previous vascular surgery. The results have been good, and we are now also using this technique for primary PCL reconstruction with favorable results.

Adolescent↗
PubMed1993

Comparison of neural network and k-NN classification methods in medical image and voice recognitions.

We make a comparison of classification ability between BPN (Back Propagation Neural Network) and k-NN (k-Nearest Neighbor) classification methods. Voice data and patellar subluxation images are used. The result was that the average recognition rate of BPN was 9.2 percent higher than that of the k-NN classification method. Although k-NN classification is simple in theory, classification time was fairly long. Therefore, it seems that real time recognition is difficult. On the other hand, the BPN method is long in learning time but is very short in recognition time. Especially if the number of dimensions of the samples is large, it can be said that BPN is better than k-NN in classification ability.

Algorithms↗
PubMed1993

Long-term follow-up study on the Maquet procedure with special reference to the causes of failure.

Thirty-nine patients with symptomatic osteoarthrosis (OA) of the patellofemoral joint were treated with 42 anterior tibial tubercle elevations, also known as the Maquet procedure. The patients all had symptomatic OA of the patellofemoral joint that fell into one of three categories: old patellar fracture, chronic patellar subluxation, or postpatellectomy pain. In the latter group, the OA was manifested by erosions of trochlear articular cartilage from the articulating quadriceps tendon-patellar ligament suture line. All 39 patients had a 1.5-2.5-cm tibial tubercle elevation with medial displacement, as necessary, to centralize their patellofemoral mechanisms. Follow-up period averaged 6.1 years. Seventy-nine percent (33 of 42 procedures) had good to excellent results. There was a major complication rate of 7%. Six of the nine failures were attributable to social/psychiatric reasons. Previously unrecognized tibiofemoral OA was the reason for poor results in two of the other failures, and one failure was unexplained. Patients with long-standing symptoms caused by patellofemoral OA should preoperatively be psychologically evaluated and diagnostically arthroscoped before the Maquet procedure is carried out.

Adolescent↗