Lateral meniscal cyst causing common peroneal palsy

Arthroscopic Management of Meniscal Cysts: A Systematic Review

Purpose

The purpose of this study was to systematically review the outcomes of arthroscopic management of meniscal cysts and to compare the results across the reported surgical techniques.

Methods

Following the PRISMA methodology, 3 databases (PubMed, Scopus and Web of Science) were searched from inception to June 2021 for randomized controlled trials (RCTs) and observational studies reporting outcomes on patients with meniscal cysts who underwent arthroscopic surgery. The Mixed Methods Appraisal Tool (MMAT) was used to evaluate the study quality.

Results

Eighteen studies examining 753 patients (761 meniscal cysts; 92.5% in the lateral meniscus) were included. Overall, 486/736 (66.0%) patients underwent purely arthroscopic decompression, 174/736 (23.6%) received arthroscopic excision, 58/736 (7.9%) received arthroscopy assisted percutaneous drainage, and 18/736 (2.4%) received a combined procedure. The recurrence rate for meniscal cysts was 7.1% across all arthroscopic procedures; 8.3%, 3.4%, and 0% for arthroscopic decompression, arthroscopic excision, and arthroscopy assisted percutaneous drainage, respectively. A total of 79.3% of patients returned to the same level of sport and 85.7% had resolution or minimal knee symptoms after arthroscopic surgery for meniscal cysts. Patient perception of surgical outcomes after any type of arthroscopic surgery for meniscal cysts was reported by 5 studies, with 189/203 (93.1%) reporting satisfaction with their surgical procedure.

Conclusion

Based on current evidence, arthroscopic management of meniscal cysts yields satisfactory patient outcomes, low cyst recurrence rates and high return to sport rates regardless of the surgical technique. Rates of cyst recurrence were relatively higher with arthroscopic decompression versus excision and percutaneous drainage; however, prospective studies using modern surgical techniques are necessary to better evaluate the surgical outcomes and to compare those with nonoperative modalities, given that a significant proportion of the included articles in this review were relatively outdated.

Level of Evidence

Systematic review of level II and IV studies.

Peroneal neuropathy caused by an extraneural ganglion cyst in the supracondylar area of the femur: A case report

RATIONALE

Peroneal neuropathy is the most common type of peripheral neuropathy in the lower extremities. The peroneal nerve is usually compressed at the lateral aspect of the fibular head. Compression by ganglion cysts are one of the numerous underlying etiologies for peroneal nerve neuropathy and are most frequently located around the fibular neck and proximal tibiofibular joint. To the best of our knowledge, this is the first report of an extraneural ganglion cyst located at the level of the distal thigh that resulted in compressive peroneal neuropathy.

PATIENT CONCERNS

We report a case of a 56-year-old man with sudden onset of left foot drop and gait disturbance caused by an extraneural ganglion cyst located in the popliteal fossa.

DIAGNOSIS

Electrodiagnosis (EDX) suggested a peroneal nerve lesion. Subsequently, diagnostic ultrasonography (USG) revealed a cystic mass located within the left side of the supracondylar area of femur. Further magnetic resonance imaging confirmed that the mass was located at the proximal of popliteal fossa.

INTERVENTIONS

Surgical excision was performed using a direct posterior approach. The cystic mass was compressing the common peroneal nerve, and was carefully and completely removed ensuring that all nerve branches were protected.

OUTCOMES

A histopathologic evaluation confirmed the diagnosis of a ganglion cyst. There were no postoperative complications. Two months after the surgery, follow-up USG revealed no evidence of cyst recurrence or residual lesions. Six months after the surgery, the ankle dorsiflexor motor power improved and he experienced less pain and hypoesthesia.

LESSONS

Physicians should bear in mind that the peroneal neuropathy can occur because of the ganglion cyst in the distal thigh. The thorough evaluation of EDX and USG is crucial for the early diagnosis and surgical intervention, although there is no abnormal finding around the fibular neck.

Lateral meniscal cyst causing irreversible peroneal nerve palsy

We report an unusual case of irreversible foot drop occurring secondary to a large lateral meniscal cyst. We discuss the presentation and management of this rare case and highlight some of the less common causes of foot drop.