The most common symptom of a lateral meniscal cyst is pain. It usually worsens with activity. The patient may also notice swelling or mass in the lateral joint line that varies in size with activity. These symptoms are classical for cysts associated with a meniscal tear. In some cases, a larger cyst can be mistaken for a popliteal cyst if it manifests posteriorly into the popliteal space.
1. Introduction
In order to make the correct diagnosis of this condition, physical therapists must take into account various clinical factors, including the patient’s history and examination findings, the results of diagnostic imaging, and the patient’s response to physical therapy interventions. To this end, the authors describe two case reports of patients with lateral meniscal cysts and describe the treatment options.
A meniscal cyst is most often associated with a tear in the meniscus. A ruptured meniscus allows fluid to build up and cause a cyst. Surgical treatment for meniscal cysts usually requires decompression of the cyst to relieve symptoms.
The first step in diagnosing a meniscal cyst is to get a musculoskeletal ultrasound. This procedure is very accurate and can often be performed in a clinic setting. Depending on the location of the cyst, this procedure can provide the patient with a diagnosis and treatment within one day.
2. Discussion
The symptoms of a lateral meniscal cyst are characterized by a swelling of the medial knee. The diagnosis is usually made by using MRI. However, musculoskeletal ultrasound is also an option for diagnosis and treatment. A musculoskeletal ultrasound guided percutaneous aspiration can provide symptomatic relief with a minimally invasive procedure.
Meniscal cysts are caused by tears in the meniscal cartilage. This can occur after an injury or from the gradual degeneration of the meniscus. Although meniscal cysts can be removed, the best treatment is to repair the tear and prevent the cyst from recurring.
In the present case, a 33-year-old male presented with swelling in the medial knee and a lateral meniscal cyst. This particular case was rarely reported in the literature and was successfully treated surgically. Twelve months after surgery, the patient experienced no recurrence of the cyst. In the majority of cases, the cyst corresponded to a meniscal cyst arising from the ipsilateral meniscus.
3. Conflict of Interests
A systematic review of published studies on the diagnosis and treatment of a lateral meniscal cyst has found a high level of heterogeneity among the included articles. Most of the articles reviewed were conducted more than a decade ago, and some employed outdated surgical techniques. In addition, most of the included articles were retrospective and included no prospective studies. Despite this, the authors of the review report no conflicts of interest.
The etiology of a meniscal cyst remains controversial, but it is generally associated with chronic infections, hemorrhages, and connective tissue mucoid transformation. It has also been linked to arthritic lesions and synovial fluid collection.
4. Aetiology
A 26-year-old male presented with pain in the left lateral knee. Examination revealed a 2 x 2 cm mass. The mass was tender to palpation. Lachman’s, Mcmurray, and Ober tests were negative. An ultrasound examination revealed an anechoic cyst in the lateral meniscus. The patient was diagnosed with lateral meniscal cyst and underwent nonoperative management. The cyst was aspirated and injected under ultrasound guidance.
The etiology of meniscal cysts is complex and varied. They can develop from a number of traumatic events. Trauma can cause a contusion within the meniscus substance, which can lead to meniscal degeneration. Over time, degeneration in the menisci can lead to local necrosis and mucoid degeneration. In addition, synovial cells can be displaced into the meniscus through microscopic tears in the fibrocartilage.
The menisci are cartilage structures that sit between the thigh bone femur and tibia. They are connected to the knee joint by the superior and inferior lateral genicular arteries. While menisci may be avascular during childhood and young adulthood, their vascularity decreases after weight bearing begins. In the fourth decade of life, they are mostly composed of synovial tissue and capsule cells.
5. Symptoms
Musculoskeletal ultrasound is an excellent tool for diagnosing meniscal cysts. This non-invasive imaging procedure is performed in a clinic setting and may provide a diagnosis the same day. Musculoskeletal ultrasound can reveal the presence of a meniscal cyst and its location.
A meniscal cyst may develop as a result of chronic medial or lateral tears to the meniscus. They are most common in the lateral meniscus. Surgical treatment can be performed to remove a cyst. A small curved curet may be inserted into the central portion of the cyst. If a meniscal cyst is large enough, it can dissect through the joint capsule and collateral ligaments and enter the soft tissues for considerable distances.
In some cases, a meniscal cyst is asymptomatic. However, it may be related to another musculoskeletal condition. Meniscal cysts can develop as a result of trauma, a ruptured meniscus, or a degenerative process. They can also develop in older people. When they are large, cysts can also lead to bone erosion.
6. Investigations
A 26-year-old man presented with pain in the lateral aspect of the left knee. He had no history of trauma. MRI of the knee revealed a mass measuring 2 cm in diameter at the lateral joint line. The overlying skin was normal and non-tender. His Mcmurray, Ober, and Lachman’s tests were negative. Diagnostic ultrasound revealed a cystic lesion located in the lateral meniscus. It was non-vascular and anechoic, indicating parameniscal cyst. The patient underwent nonoperative management, involving aspiration and injection of the cyst under ultrasound guidance.
Although MRI is the preferred modality for diagnosing meniscal cysts, musculoskeletal ultrasound is a valid diagnostic tool for this disease. It can be performed in the clinic and is effective for identifying and treating meniscal cysts. Ultrasound-guided percutaneous aspiration is a quick, convenient, and effective procedure. In addition, this treatment can provide long-term symptom relief.
The authors of the systematic review noted that a large proportion of the included studies were conducted more than 10 years ago. This is a limitation given the small number of patients with meniscal cysts and their need for surgical management. However, this systematic review demonstrates the need for larger investigations using the latest arthroscopic techniques.
7. Management
Management of a Lateral Meniscal cyst should begin with a thorough assessment. Radiographs are often helpful in diagnosing the cyst. Radiographs may also reveal bony erosion under the cyst. Surgery is necessary only if the cyst is preventing normal movement of the knee.
An MRI is considered the gold standard when diagnosing a meniscal cyst because it can visualize the cyst and evaluate the menisci. However, this test is costly and not appropriate for everyone. There are some patients who cannot undergo MRI, so a musculoskeletal ultrasound may be a more appropriate option.
The MRI results should be interpreted carefully. Abnormalities may be the result of normal aging of the menisci. The examiner should confirm the diagnosis and determine if the patient is suffering from meniscal problems or damage to the articular cartilage. If surgery is necessary, the patient should undergo an arthroscopy, a procedure that involves making a thin incision through the joint. The doctor can then examine the affected area with a specialized camera.
