Anterior cruciate ligament mucoid degeneration
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At the time the article was created Frank Gaillard had no recorded disclosures.View Frank Gaillard's current disclosures
At the time the article was last revised Dai Roberts had no recorded disclosures.View Dai Roberts's current disclosures
Anterior cruciate ligament (ACL) mucoid degeneration, along with tears and anterior cruciate ligament ganglion cysts, is a relatively common cause of increased signal within the anterior cruciate ligament (ACL). The appearance can mimic acute or chronic interstitial partial tears of the ACL. However, in the case of mucoid degeneration secondary signs of an ACL injury are usually absent. Secondary signs include bone bruising, meniscal tears, anterior subluxation of the tibia and other ligamentous injuries.
ACL mucoid degeneration is present on ~10% (range 9-12%) of 3 T MRI examinations and 2% of 1.5 T MRI examinations 6.
Typically patients present with knee pain or restricted movement, although often other potential causes for the patient's symptoms are found.
The pathogenesis remains controversial. Possible etiologies include:
- age-related (senescent) degeneration
- congenital or acquired synovial tissue entrapment between ACL fibers
It is postulated that mucoid degeneration may be a predisposing factor in the formation of ACL ganglion cysts.
MRI is better at detecting mucoid degeneration than arthroscopy, as the surface of the ligament is often intact.
Treatment and prognosis
No treatment is usually required. If arthroscopy is performed, the ligament may appear entirely normal, especially using the standard anterior portal approach. A posterior approach will allow for the detection of changes by probing the ligament and mucoid material can be expressed.
It has recently been postulated that mucoid degeneration of the ACL is related to the medial knee compartment joint space loss in patients with osteoarthritis or in the OA risk group 6.
- 1. Roberts CC, Towers JD, Spangehl MJ et-al. Advanced MR imaging of the cruciate ligaments. Magn Reson Imaging Clin N Am. 2007;15 (1): 73-86. doi:10.1016/j.mric.2007.02.006 - Pubmed citation
- 2. Bergin D, Morrison WB, Carrino JA et-al. Anterior cruciate ligament ganglia and mucoid degeneration: coexistence and clinical correlation. AJR Am J Roentgenol. 2004;182 (5): 1283-7. AJR Am J Roentgenol (full text) - Pubmed citation
- 3. Resnick D, Kransdorf MJ. Bone and joint imaging. W B Saunders Co. (2005) ISBN:0721602703. Read it at Google Books - Find it at Amazon
- 4. Papadopoulou P. The celery stalk sign. Radiology. 2007;245 (3): 916-7. doi:10.1148/radiol.2453050159 - Pubmed citation
- 5. Cho SD, Youm YS, Lee CC et-al. Mucoid degeneration of both ACL and PCL. Clin Orthop Surg. 2012;4 (2): 167-70. doi:10.4055/cios.2012.4.2.167 - Free text at pubmed - Pubmed citation
- 6. Kwee RM, Hafezi-Nejad N, Roemer FW, Zikria BA, Hunter DJ, Guermazi A, Demehri S. Association of Mucoid Degeneration of the Anterior Cruciate Ligament at MR Imaging with Medial Tibiofemoral Osteoarthritis Progression at Radiography: Data from the Osteoarthritis Initiative. (2018) Radiology. 287 (3): 912-921. doi:10.1148/radiol.2018171565 - Pubmed