The pathological plica in the knee. Results after arthroscopic resection

Arthroscopic treatment of symptomatic lateral synovial plica of the knee

INTRODUCTION

Synovial plicae are often observed when performing arthroscopic surgery, but their pathological nature and the necessity for treatment are still controversial. There are few reports regarding lateral synovial plicae because it is considered extremely rare. The purpose of this study was to report the clinical outcomes of athletes with symptomatic lateral synovial plicae who underwent arthroscopic surgery.

METHODS

Ten patients with lateral synovial plica underwent arthroscopic surgery. Of the 10 patients, 5 were male and 5 were female, and their average age was 19.1 years. The chief symptoms were anterolateral knee pain, limited range of motion due to pain, and catching. All patients failed nonoperative management.

RESULTS

The average period between the onset of lateral synovial plica syndrome and the knee surgery was 5.6 months. The average follow-up period after surgery was 8.4 months. The arthroscopic findings revealed that a plica-like structure existed in the lateral patellofemoral joint. After surgery, pain and limited range of joint motion were improved in all cases and catching and locking disappeared. No complications were observed; however, the pain relapsed after surgery in one patient who had slow onset. In this patient, another resection of the synovial plica provided symptomatic improvement.

CONCLUSIONS

Arthroscopic resection of symptomatic lateral synovial plicae was performed with good results. Lateral synovial plica syndrome is a rare condition. However, when treating athletes with anterolateral knee pain, lateral synovial plicae should be considered.

'The Sneaky Plica' revisited: morphology, pathophysiology and treatment of synovial plicae of the knee

PURPOSE

To comprise current knowledge on morphology, embryology and pathophysiology of synovial plicae as well as on clinical and therapeutic aspects of the plica syndrome.

METHODS

Review of the literature combined with a meta-analysis of studies assessing the outcome of open or arthroscopic plica excision including the author's own series.

RESULTS

The term synovial plica has been devised to describe a number of intra-capsular folds thought to represent remnants of a membranous knee joint partition present during foetal development. Although four such folds have been defined, it is mainly the medial patellar plica which is implicated in carrying clinical significance as a potential cause of anteromedial knee pain particularly in adolescents. Blunt trauma, a sudden increase in athletic activity or any form of transient synovitis are associated with plica inflammation leading to tissue fibrosis and subsequent loss of elasticity. A plica affected in this way may impinge against intra-articular structures in its proximity, often creating localised chondromalacia particularly of the patello-femoral joint. The diagnosis is based on history and clinical examination although MRI can be of value. Twenty-three studies assessing the clinical out-come of 969 patients following open or arthroscopic plica excision were identified. The average age was 25 years with equal male-to-female ratio. Trauma was considered the cause in 57 %. At a mean follow-up of 27.5 months, 64 % of patients were symptom free, 26 % improved and 10 % considered failures.

CONCLUSION

Symptomatic plicae may initially be treated with physiotherapeutic measures and structured exercise regimes but success rates are generally low. Intra-plical or intra-articular corticosteroid injections may be beneficial if administered early in the disease process. Arthroscopic excision of the entire plical fold becomes indicated in recalcitrant cases and once a plica has undergone irrevocable morphological changes. The procedure carries low morbidity, and results are universally good especially if the plica is the sole pathology. Factors associated with a favourable outcome are young patient age, localised symptoms of short duration and absence of plica induced chondromalacia.

Synovial plicae around the knee

Synovial plicae around the knee are a relatively common occurrence but one that is rarely responsible for symptoms. The Plica syndrome has been well described but controversy still exists regarding its diagnosis and treatment. We have reviewed and studied the published literature both past and present in detail regarding synovial plicae around the knee to provide a comprehensive and up-to-date review on the subject. The aim is to outline previous significant research into the embryology and pathology of synovial plicae as well as providing a review of the current thinking on treatment options available for the different synovial plicae with reference to the evidence available.

Arthroscopic resection of medial plica of the knee in young adults

The purpose of this study was to evaluate the long-term results of arthroscopic resection of a medial plica and to describe the usefulness of the clinical findings and MRI for preoperative diagnostics. From the baseline population of 172,777 military conscripts, thirty-three consecutive young adult patients with normal preoperative MRIs of the knee and a sole postoperative diagnosis of medial plica were treated with arthroscopic plica resection. Functional outcome was evaluated at a final follow-up in 25 patients with 34 knees with Kujala, Lysholm and visual analog scale (VAS) scores. Functional results were excellent to good in 17 patients, fair in three patients, and poor in 3 patients. The median Kujala score was 92 (25-100), the median Lysholm score 89 (26-100), and the median VAS 1.4 (0-8.8). Median follow-up time was 6.6 years (3.6-8.7 years). Most patients had no history of direct knee trauma preceding the symptoms. No statistically significant correlation was seen between MRI classification of the plica size or clinical findings compared to arthroscopic classification. Resection of the medial plica in a symptomatic knee has good to excellent functional long-term outcome in the majority of cases, and the procedure is not associated with postoperative complications. MRI and preoperative clinical examination seem to be unreliable in detecting medial plicae.

Treatment of pathological synovial plicae of the knee

OBJECTIVE

To analyze the incidence, clinical significance, and clinical manifestations of pathological synovial plicae of the knee.

MATERIAL AND METHODS

Between 2002 and 2006, 63 patients with pathological synovial plicae of the knee were studied. Of those 63 patients, 21 had the diagnosis confirmed by previously performed magnetic resonance imaging. All of the patients initially underwent conservative treatment for 90 days that involved strengthening and improving the flexibility of the muscles surrounding the knee as well as modification of their sports activities.

RESULTS

A total of 55 patients improved after conservative treatment. Six of these patients eventually experienced a recurrence of symptoms, but the symptoms were not incapacitating in any of these patients. The other eight patients underwent arthroscopic removal of the synovial plica. Of these eight patients, six returned to their pretreatment physical activities, and two had persistent symptoms during physical activity.

CONCLUSION

The presence of a synovial plica of the knee should be considered as a potential diagnosis in patients with knee pain, especially those who practice sports inappropriately. Conservative treatment is effective in most cases, and surgical treatment should be reserved for exceptional cases that do not improve with conservative treatment.

Retinacular band excision improves outcome in treatment of plica syndrome

Mild symptoms usually continue after excision of the medial patellar plica. We noticed that the palpable tender cord, located on the anteromedial aspect of the knee in patients with plica syndrome, did not disappear completely after excision of the synovial fold. Beneath all plicae, a retinacular band was visible, and only after excisions of this band did the cord become impalpable. We conducted a study to determine the role of these medial retinacular bands in the symptomatology of the disorder. Twenty-four knees of 22 patients diagnosed with medial patellar plica syndrome were divided into two groups. In the first group, arthroscopic excision of the synovial plica was performed. In the second group, retinacular bands beneath the plica were additionally excised. When Lysholm scores were compared, we found that the second group showed significantly greater improvement. We believe that the retinacular bands play a role in the symptomatology and the pathophysiology of plica syndrome and that excision improves the outcome.

Arthroscopic findings in the knees of preadolescent children: report of 23 cases

PURPOSE

The aim of this review was to correlate the preoperative clinical diagnoses and the diagnostic arthroscopic findings in preadolescents with knee problems. We also studied the incidence of different types of knee pathology in this age group.

TYPE OF STUDY

Consecutive case series.

MATERIALS AND METHODS

Twenty-three preadolescents, 13 girls and 10 boys under the age of 13 years, presenting with mechanical knee problems underwent knee arthroscopy after clinical assessment.

RESULTS

Symptomatic plica synovialis was found to be the most frequent pathology (n = 8). This pathology was far more common in girls compared with boys. Anterior cruciate ligament injuries (n = 4) followed symptomatic plica synovialis in frequency. This was an isolated injury in all cases. The arthroscopic findings were negative in 4 patients.

CONCLUSION

In 61% of preadolescent patients, the clinical diagnoses and arthroscopic findings were compatible and correct. The main error tended to be misdiagnosis of meniscal pathology (4 patients) and overdiagnosis (5 cases of negative arthroscopy).

The plica syndrome: diagnostic value of MRI with arthroscopic correlation

PURPOSE

Our goal was to evaluate the diagnostic value of MRI in plica syndrome.

METHOD

MR images of a patient group (n = 55) with arthroscopically confirmed pathologic mediopatellar plicae were retrospectively analyzed and compared with those of a control group (n = 100). We obtained axial multiplanar gradient-recalled (MPGR), axial T1-weighted, and sagittal T2-weighted MR images. MR images were assessed for the width and length of all medial plicae.

RESULTS

In the diagnosis of plica syndrome, sensitivity and specificity were 73 and 78% on axial MPGR images, 71 and 83% on sagittal T2-weighted images, and 95 and 72% on combination of both images, respectively. The incidence of pathologic medial plica increased with a criterion of extension beyond the medial end of the patella on axial MPGR images.

CONCLUSION

MRI is a useful screening method in the diagnosis of plica syndrome.

Synovial plicae of the knee. Controversies and review

Plicae are some of the normal synovial structures of the knee joint cavity. They are remnants of the mesenchymal tissue that occupies the space between the distal femoral and proximal tibial epiphyses in the 8-week-old embryo. The incomplete resorption leaves synovial pleats in most of the knee. The superior and the inferior plicae are the most common (50% to 65%) but have extremely little clinical relevance. Each may be of many various morphological types. The lateral plica is rare (1% to 3%). The medial plica is present at autopsies in one of every three or four knees. It also is of various types, wide and thick in one of every fifteen knees. Arthrography, ultrasonography, CT scan with arthrography, and MR imaging can demonstrate their presence and measure their size with good accuracy. Arthroscopy allows a very precise assessment of the plica, including dynamic examination. It looks for medial impingement against the patellofemoral articular surfaces and secondary (localized chondromalacia) as well as incidentally associated other knee pathologic conditions. Rarely, the medial plica becomes symptomatic, circumstances such as a history of blunt trauma, or more often, overuse of the knee can cause symptoms. Sometimes no special condition is necessary. The plica causes symptoms such as pain, crepitus, snapping or popping, or effusion related to patellofemoral joint motion. The clinical picture mimics a torn medial meniscus or a maltracking patella. Clinical examination is extremely helpful if the snapping plica is palpated at the medial edge of the patella, reproducing the patient's symptoms. If chronic, these symptoms may be treated with nonsteroidal anti-inflammatory drugs, physiotherapy, electrophoresis, or local injection. Surgical treatment is indicated if conservative therapy fails. Arthroscopic complete resection of the plica cures the symptoms in a few days, therefore confirming the correct diagnosis and the effectiveness of the treatment. Histologic examination often confirms the chronic conflict between the plica and the femoral condyle. No morphologic character allows the assessment of the pathologic aspect of the plica. A medial plica is or is not symptomatic. The incidence of this syndrome is probably one out of ten medial plicae and 3% of arthroscopies at most. Associated lesions are very common. They often make the evaluation of the plica's responsibility in symptoms difficult to analyze, leading to unsatisfactory results.

MR evaluation of mediopatellar plica

PURPOSE

Evaluation of the usefulness of MR imaging for diagnosing mediopatellar plica (MP) of the knee joint.

MATERIAL AND METHODS

We prospectively examined MR images of 40 knee joints in 30 patients with symptoms. The pulse sequences were SE T1-weighted images (600/26 ms), T2-weighted images (1800/70), and FLASH images (320/15/flip angle 90 degrees). When a low-intensity band was found above the medial condyle of the femur on T1-weighted and T2-weighted MR images, we defined it as MP. We compared these MR findings with arthroscopic findings, including the SAKAKIBARA classification of MP.

RESULTS

In 29 of the 40 knee joints in which MP was arthroscopically found, 27 were correctly diagnosed as having MP on MR. In the remaining 11 without MP, 9 were correctly diagnosed by MR.

CONCLUSION

MR images are useful not only for detecting MP but also for evaluating its extension. Our results suggest that MR imaging is useful as a screening method for detecting MP before arthroscopy.

Symptomatic synovial plicae of the knee

Forty-five knees (thirty patients) with a specific diagnosis of synovial plica syndrome, and without any other known lesion, were randomized to be treated with either diagnostic arthroscopy alone or arthroscopy and division of all plicae. The diagnosis of synovial plica syndrome had been made on the basis of intermittent pain in the anterior aspect of the knee, painful clicking with activity, giving-way, and a palpable, tender plica. The patients were selected for arthroscopy only if the symptoms had continued unabated after a course of physical therapy. At the time of follow-up, improvement had occurred in only six (29 per cent) of the twenty-one knees in which the plicae had not been divided, in contrast with twenty (83 per cent) of the twenty-four knees in which they had been divided (p < 0.001). Ten (48 per cent) of the knees in which arthroscopic division had not been done were treated with another arthroscopic operation. Seven of these ten knees improved after the subsequent division of the plicae (p < 0.01). We concluded that synovial plicae of the knee may be a definite cause of anterior pain in children and adolescents.