What is the diagnosis and treatment of a cyclops lesion in the knee?

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Last updated: April 17, 2025View editorial policy

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From the Research

Arthroscopic removal of the cyclops lesion is the most effective treatment for restoring knee extension and reducing pain in patients with cyclops syndrome after anterior cruciate ligament (ACL) reconstruction surgery. This procedure, which can be performed using a minimally invasive approach with a needle arthroscope, allows for the excision of the fibrous tissue and restoration of full range of motion 1. The rehabilitation protocol after surgery typically includes range-of-motion exercises, progressive strengthening, and gradual return to activities over 4-6 weeks 2.

Causes and Prevention

Cyclops lesions develop due to an inflammatory response to tissue debris or graft material that becomes trapped in the intercondylar notch during ACL healing 3. Prevention strategies include thorough debridement during the initial ACL reconstruction and proper rehabilitation emphasizing early extension exercises 2.

Diagnosis and Treatment

Diagnosis of a cyclops lesion can be made using magnetic resonance imaging (MRI) or diagnostic ultrasound (US) 4. Treatment usually involves arthroscopic removal of the lesion, which is a minimally invasive procedure where the surgeon uses small incisions to access and excise the fibrous tissue 1.

Outcomes

Most patients experience significant improvement after removal of the cyclops lesion, with restored knee extension and reduced pain, allowing return to normal activities and sports [(2,5)]. The use of a needle arthroscope for excision of the cyclops lesion may result in decreased postoperative pain and swelling, and a quicker recovery 1.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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