Heparin immobilized on proteins usable for arterial prosthesis coating: growth inhibition of smooth-muscle cells

Fifty-one patients with meniscal repair using the outside-in technique were reassessed with second-look arthroscopic procedures (N = 15), arthrographic examination (N = 41), magnetic resonance imaging (N = 36), or a combination of these techniques. Forty-one medial and 10 lateral menisci were repaired. The average clinical follow-up was 15 months (range, 3 to 80). Forty-five of 51 patients had tears that were located in or extended into the posterior horn of the medial or lateral meniscus. Complete healing occurred in 23 menisci (45%), partial healing was observed in 16 (15 medial, 1 lateral) (32%), and no healing occurred in 12 (24%). Remarkably, in all 15 patients who had tears extending from the posterior to the middle third of the medial meniscus that were partially healed, it was always the posterior third that had not fully healed. This finding is statistically significant. In addition, the middle third of these menisci had not fully healed in five patients. No healing occurred in the two patients with tears in the posterior third of the medial meniscus. Poor healing with the outside-in technique was observed in patients with tears into the posterior horn of the medial meniscus. For tears in the middle and anterior portion of the medial meniscus, as well as all lateral meniscus tears, the outside-in technique is our current method of choice.     

Osteochondritis dissecans of the femoral condyle in the growth stage

The site of lesion, spontaneous healing, onset mechanism, and magnetic resonance imaging findings of 51 knees in 38 patients with osteochondritis dissecans involving the femoral condyle in the growth stage were investigated. tercondylar site, and the remaining 1/4 were in other sites. Compared with those in the other sites, the lesions in a medial intercondylar site had a lower healing rate and required a longer time to heal. T2 weighted images of the lesions showed a progression from low signal areas to the appearance of a high signal line at the fragment to parent to bone interface, to a high signal double line at the interface and parent-bone surface, or to disappearance of the line. Magnetic resonance imaging often revealed discoid menisci or meniscal tears in patients with lesions in the lateral condyle, suggesting that endogenous forces play an important role in the onset of osteochondritis dissecans.     

Technical considerations in the management of complex meniscus tears

Meniscal repair continues to be an important procedure in patients with meniscal tears. The orthopedic literature has recommended excision of complex tears or tears that are located in the central avascular region. For the past 13 years, the authors have repaired all meniscal tears that can be reduced anatomically and that have healthy tissue that will support the multiple sutures required for a stable repair, regardless of tear pattern or location. Correct patient selection criteria continue to be important. In all cases, the risks of complications and retear must be considered carefully and judged against the potential benefits of repair. A postoperative rehabilitation program that allows early range of motion, and progression of weight bearing is not detrimental to the healing process if the repair is stable. Close postoperative follow-up examinations are necessary to determine the incidence of meniscal symptoms; however, the absence of joint line pain, catching, locking, or effusion does not guarantee complete healing of the tear. Follow-up arthroscopy is currently the most accurate method to determine if complete or partial healing has occurred.     

A comparison of results in acute and chronic anterior cruciate ligament ruptures of arthroscopically assisted autogenous patellar tendon reconstruction

We conducted a prospective study of 94 consecutive patients who received a patellar tendon autograft for anterior cruciate ligament rupture. Eighty-seven patients (93%) returned for followup a mean of 28 months postoperatively; 57 had chronic and 30 had acute or subacute ruptures. There were no significant differences between the subgroups for age, sex, articular cartilage lesions, or months of followup. Forty-six meniscal tears were repaired; 27 of these extended into the central avascular region. Rehabilitation emphasized immediate knee motion, but strenuous activity was delayed for at least 4 months. Only one patient had a knee motion complication, and stability (<3 mm, KT-2000 arthrometer, 134 N) was restored in 85% of knees with chronic ruptures and 92% of knees with acute ruptures. Earlier reconstruction should be considered in active persons as symptoms and limitations continued postoperatively in knees with chronic ruptures, leading to overall less satisfactory results. In patient rating of the overall knee condition, 69% of knees with chronic ruptures and 100% of knees with acute ruptures scored in the normal or very good range. Repair of meniscal tears that extend into the central avascular region should be considered, as 24 of the 27 (89%) menisci repaired showed clinical evidence of healing and did not require reoperation.     

Intraarticular anatomic variants associated with discoid meniscus in Koreans

From July 1990 through June 1994, 106 knees (102 patients) were treated for discoid meniscus. Fifteen knees (15 patients) were associated with other intraarticular anatomic variants. There were eight knees (8 patients) with anomalous insertion of the anterior horn of the medial meniscus into the anterior cruciate ligament, and seven knees (7 patients) with anterior expansion of the anterior portion of the anterior cruciate ligament below the anterior tibial margin. Among the latter, one patient also had anterior transposition of the anterior insertion of the medial meniscus, while obliteration of the popliteal hiatus was seen in another patient. The discoid menisci were reshaped in 13 knees (13 patients), totally resected in one knee, and in one patient the discoid meniscus was treated with repair of a peripheral tear and reshaping. Followup ranged from 24 to 54 months (average, 37 months) after surgery. The results were excellent in eight knees, good in five knees, and fair in two knees as graded using the Ikeuchi scale. These anatomic variants, other than the discoid meniscus, did not seem to be related to the patient's symptoms.     

Relationship of the meniscofemoral ligaments of the knee to lateral meniscus tears: magnetic resonance imaging evaluation

This study sought to determine if the presence or absence of meniscofemoral ligaments exerts an influence on the prevalence of tears of the lateral meniscus. We reviewed the sagittal and coronal magnetic resonance images of 173 knees for lateral meniscus tears and the presence of the meniscofemoral ligaments. One or both meniscofemoral ligaments were present in 142 of 173 knees (82%). Fifty-four knees had lateral meniscus tears, 27 of which involved the posterior horn. Thirty-three percent of knees with meniscofemoral ligaments had a lateral meniscus tear, and 23% of knees without meniscofemoral ligaments had a lateral meniscus tear (no significant difference). We found no association between the presence of the meniscofemoral ligaments and tears of the lateral meniscus. Our study questions the importance of preserving or reconstructing these ligaments in instances of meniscal transplantation.     

Clinical results of meniscus repair in patients 40 years and older

The critical role that the meniscus plays in the knee along with the advantages of preserving as much of the meniscus as possible have both been well documented. Whenever possible, meniscus repair has become the procedure of choice for treatment of meniscal tears. However, some researchers have reported less favorable results in older patients. To determine the results of meniscus repair in older patients, patients 40 years and older who underwent arthroscopically assisted meniscus repair were prospectively followed up. Thirty-seven patients were included in the study, all of which had a minimum 2-year follow-up (average, 26.5 months). The average age of the patients at the time of the repair was 44.2 years (range, 40 to 52 years); 26 were males and 11 were females. There were 19 left knees and 18 right knees included in the study. Twenty-two patients had associated anterior cruciate ligament reconstructions. Physical examination at follow-up included swelling, joint line tenderness, locking, and McMurray testing and radiographs. Five of 37 menisci repaired (13.5%) were symptomatic at latest follow-up. All of these patients had joint line tenderness and two had a positive McMurray test. Three of these patients had repeat arthroscopy confirming that the meniscus had not healed. Because of the small number of patients with symptoms at follow-up, the authors feel that meniscus repair in patients 40 years and older is an effective treatment for peripherally located meniscus tears. With 86.5% of the patients having good clinical results, these findings are comparable with other studies with a younger population and signify that repair of peripheral tears is indicated in this age group especially in conjunction with anterior cruciate ligament reconstruction. The findings suggest that the location and meniscal tear, rather than the age of the patient, determine the potential for successful repair.     

Intermediate-term results of meniscal repair in anterior cruciate ligament-reconstructed knees

We investigated the incidence of and risk factors for recurrent tears of repaired menisci in anterior cruciate ligament-reconstructed knees. We observed 63 patients whose menisci had been evaluated at second-look arthroscopy as healed (N = 50) or incompletely healed (N = 13) for an average of 4 years (range, 2 to 9.5). Of the 13 patients with incompletely healed menisci, 6 (46%) required additional meniscal surgery and 2 (15%) had recurrence of meniscal symptoms such as catching or locking. Among the 50 patients with healed menisci, 5 (10%) required additional meniscal surgery and 9 (18%) had recurrence of meniscal symptoms after second-look arthroscopy. The timing of the recurrence of these symptoms was from 12 to 28 months after surgical repair. Of the 11 patients who had undergone additional surgery, 6 had sustained second injuries during sports activities and the other 5 had no identifiable cause of injury. When comparing age, tear sites, rim width, side-to-side differences with KT-1000 arthrometer testing, and the pivot shift test, there were no differences between the group requiring additional surgery, the symptomatic group, and the asymptomatic group. However, the postoperative Tegner activity score of the group requiring additional surgery was statistically significantly higher than the others.     

Magnetic resonance imaging arthrography of the ankle

Magnetic resonance imaging (MRI) arthrography of the ankle is a useful diagnostic modality in the detection and staging of lateral ankle ligament tears, particularly in patients who fail to respond to conservative management. MRI arthrography also may be helpful in determining the extent of ligamentous injury in professional athletes, for whom immediate surgical repair may be the initial treatment. Preoperative planning is optimized with MRI arthrography. Frequently, alternative diagnoses may be made for conditions that can simulate lateral ligamentous injury, thus obviating the need for diagnostic arthroscopy.     

Influence of magnetic resonance imaging on indications for arthroscopy of the knee

In a prospective study, magnetic resonance imaging was performed before arthroscopy for all patients (n = 121) with a meniscal tear (n = 125). Criteria of the study were stable cruciate and collateral ligaments, absence of pathologic radiographic findings, and absence of prior surgical interventions of the involved knee joint. In 43 knees (34%), the clinical diagnosis of a meniscal tear was discarded because of the results of the magnetic resonance imaging examination. Synovitis was diagnosed in 16 patients (13%), articular cartilage damage in 10 patients (8%), bone bruise injuries in 10 patients (8%), osteochondritis dissecans in 3 patients (2%), disruption of the inner layer of the medial collateral ligament in 3 patients (2%), and osteonecrosis in 1 patient. The use of magnetic resonance imaging in establishing diagnosis of disorders of the knee joint altered treatment in a significant proportion of patients. Magnetic resonance imaging should be done before arthroscopy of the knee in all cases in which the clinical diagnosis has been reduced to a suspected meniscus injury.     

Glenohumeral instability: evaluation with MR arthrography

Magnetic resonance arthrography is superior to other imaging techniques in evaluation of the glenohumeral joint. Normal variants that can be diagnostic pitfalls include the anterosuperior sublabral foramen, the Buford complex, and hyaline cartilage under the labrum. Anteroinferior dislocation is the most frequent cause of anterior glenohumeral instability and produces a constellation of lesions (anteroinferior labral tear, classic and osseous Bankart lesions, Hill-Sachs lesion). Variants of anteroinferior labral tears include anterior labroligamentous periosteal sleeve avulsion and glenoid labral articular disruption. Anterior glenohumeral instability can also involve tears of the anterior or anterosuperior labrum or the glenohumeral ligaments. Posterior glenohumeral instability can involve a posterior labral tear, posterior capsular stripping or laxity; fracture, erosion, or sclerosis and ectopic ossification of the posterior glenoid fossa; reverse Hill-Sachs lesion; McLaughlin fracture; or posterosuperior glenoid impingement. Superior labral anterior and posterior lesions involve the superior labrum with varying degrees of biceps tendon involvement.     

Arthroscopic treatment of cysts of the lateral meniscus

We have treated 69 patients with 72 cystic lateral menisci by arthroscopic surgery. Meniscal tears were observed in all cases, and 69 of these had a horizontal cleavage component. Three types of tear were identified and may be progressive. Treatment was by arthroscopic resection of the meniscal tear, and decompression of the cyst through the substance of the meniscus. After a mean follow-up of 34 months the results were good or excellent in 64 knees (89%) and there were few complications. We recommend this technique as the treatment of choice for cysts of the lateral meniscus.     

Influence of the status of the contralateral carotid artery on the outcome of carotid surgery

This is a preliminary report of four cases of meniscal displaced tears: two bucket handle medial meniscus tears, one complex tear in the avascular zone or lateral meniscus, and one longitudinal full-thickness tear on the lateral meniscus. These tears were treated by applying hi-frequency current stimulation to the tissues and obtaining total meniscal visual healing on a second arthroscopic view after 6 weeks.     

Magnetic resonance imaging of the musculoskeletal system. Part 6. The Shoulder

The role of magnetic resonance imaging in the diagnosis and treatment of patients with shoulder pain has increased remarkably in recent years, largely because of improved resolution of images and increased experience of musculoskeletal radiologists. In rotator cuff disease/impingement and instability, magnetic resonance imaging adds a new dimension to the clinical findings through the noninvasive visualization of either the pathology itself or frequently associated abnormalities. It is the associated abnormalities that are depicted in instability: glenoid irregularities, labral tears, capsular laxity, and Hill-Sachs deformities. Glenoid, labral, and Hill-Sachs abnormalities can be assessed with either magnetic resonance imaging or computed tomography arthrography. Magnetic resonance imaging has the advantages of noninvasiveness, multiplanar imaging capability and exquisite soft tissue contrast. In rotator cuff disease, magnetic resonance imaging depicts the status of the rotator cuff itself, revealing partial and full thickness tears, allowing an estimation of size and quality of tendon edges. Possible impingement sites can be identified. Primary instability with secondary impingement may be first suspected on magnetic resonance imaging. Postoperative complications, including recurrent tendon detachment, deltoid dehiscence, and infection, are clarified. Unsuspected but clinically important lesions, such as neoplasm, osteonecrosis, and ganglion with entrapment of the suprascapular nerve, each have characteristic magnetic resonance imaging appearances.     

A 2.5-Mb transcript map of a tumor-suppressing subchromosomal transferable fragment from 11p15.5, and isolation and sequence analysis of three novel genes

The purpose of this prospective study was to determine whether or not abrasion arthroplasty promotes cartilage regeneration in osteoarthritic (OA) knees with eburnation. Patients with OA knees were divided into a group of 51 knees treated by osteotomy with abrasion arthroplasty (Group A) and another group of 37 knees treated by osteotomy alone (Group B). Regeneration of cartilage was compared between the groups both arthroscopically and histologically. The Outerbridge classification was used for arthroscopic grading with Grade 0 being normal and Grade IV representing eburnation. On arthroscopic examination, around 12 months after surgery, Group A showed a significantly higher incidence of Grade II repair (a smooth articular surface and small fissures) and a lower incidence of Grade IV repair than Group B on both the femoral (P < .001) and tibial (P < .01) joint surfaces. Age was the only factor influencing the grade of tibial cartilage in Group A. Histological examination showed that 64% of the regenerated tissue studied consisted of fibro-cartilage at around 12 months after surgery. There was no difference in the clinical outcome at 2 to 9 years postoperatively between Groups A and B.     

The pharmacological profile of the vesicular monoamine transporter resembles that of multidrug transporters

Since meniscal healing is region-specific, we studied the regional (peripheral compared with central) response of meniscal explants to human, recombinant platelet-derived growth factor-AB. Meniscal explants from the hindlimbs of both knees of mature sheep were sectioned and were cultured with variable doses of human, recombinant platelet-derived growth factor-AB, and incorporation of [3H]-thymidine was measured. The mitogenic response was measured at different times in culture (48 or 96 hours) and by location (lateral or medial). In the absence of the growth factor, the peripheral third of both menisci incorporated 10-fold more [3H]-thymidine on a weight basis than did the central two-thirds. Cellularity was equivalent in the two regions. Doses of less than 100 ng/ml of growth factor produced either no stimulation or a variable response. A dose of 100 ng/ml resulted in consistent, significant (p < 0.05) stimulation in all groups in the peripheral region, and a dose of 200 ng/ml provided more than a 2.5-fold increase. Multiple-factor analysis of variance demonstrated that there were no significant differences between experiments, times in culture, or menisci. The central region did not respond to stimulation with the growth factor at any of the doses tested. These data suggest that regional differences (peripheral compared with central) in responsiveness to human, recombinant platelet-derived growth factor-AB may reflect a different level of signal transduction machinery for growth factor receptors and distinct fibrobchondrocyte populations. These findings are consistent with the variable healing capacity of the meniscal regions in vivo and suggest a pharmacological means to promote the repair of the peripheral meniscal region.     

Tears of the medial collateral ligament: magnetic resonance imaging findings and associated injuries

For 23 patients with a surgically proven tear of the medial collateral ligament the findings from magnetic resonance imaging (MRI) of the knee were evaluated retrospectively. MRI revealed the tear in all cases, although when the injury was severe, distinguishing high-grade partial tears from complete tears was difficult. Physical examination had indicated a tear in 22 (96%) of the cases. A high prevalence of associated cruciate and meniscal injuries was seen (in 23 [100%] and 12 [52%] of the cases respectively). Tears of the fibular collateral ligament occurred in 13 (57%) of the patients and at least one bony infraction in 22 (96%); most of the infractions were in the lateral compartment. Infractions of the lateral femoral condyle were frequently geographic (in 14 [70%] of the 20 cases) or impacted (in 5 [25%]). The spectrum of injuries associated with tears of the medial collateral ligament was consistent with the findings of previous studies focusing on cruciate and meniscal abnormalities; the minor variations were likely due to the severity of valgus stress in this sample.     

Patterns of meniscal tears associated with anterior cruciate ligament lesions in athletes

In this study, 400 clinically anterior cruciate ligament (ACL) deficient knees were arthroscoped and studied prospectively in the period January 1986 to April 1992. An ACL tear was always confirmed, and 41 per cent of these patients did not have an associated meniscal tear. In 30.25 per cent the lateral meniscus was torn; in 21.25 per cent the ACL tear was associated with a medial meniscus tear, and in the remaining 7 per cent both menisci were torn. The most frequently associated meniscal injury was the bucket handle tear of the medial meniscus (9 per cent), followed by the posterior horn tear of the lateral meniscus, which showed the same frequency as the ragged (or degenerated) tear of the lateral meniscus (6 per cent). The horizontal tear of the posterior part of the lateral meniscus showed a prevalence of 4.3 per cent. This picture is probably dependent on a secondary referral nature of the centre surveyed, in which the average time between injury and arthroscopy was 23.3 months.     

Magnetic resonance imaging of the musculoskeletal system. Part 4. The knee

Since its introduction to musculoskeletal imaging in the early 1980s, magnetic resonance imaging has proven to be an excellent technique for evaluating patients with knee problems. Studies have shown it to be accurate in the identification of abnormalities of the menisci, ligaments, patellofemoral joints, and other soft tissue and osseous structures in the knee. The main advantages of magnetic resonance imaging are its noninvasive nature and its high accuracy and negative predictive value in evaluating the menisci and anterior cruciate ligament. Magnetic resonance imaging has been shown to be useful in the detection and diagnosis of various traumatic and nontraumatic knee abnormalities. It has also proved useful in the diagnosis of occult or unsuspected bone lesions. Magnetic resonance imaging can therefore help in the selection of those patients who need therapeutic arthroscopy. There is evidence that magnetic resonance imaging of the knee is a cost effective screening technique when used in conjunction with the clinical findings in patients who are candidates for arthroscopy. Magnetic resonance imaging of the knee is still a relatively expensive modality.