Role of ultrasound-guided decompression in management of mucoid degeneration of the anterior cruciate ligament

Partial debridement is the most commonly reported treatment option for mucoid degeneration of the anterior cruciate ligament: a systematic review

PURPOSE

To determine clinical outcomes and risks of various management strategies for mucoid degeneration of the anterior cruciate ligament (MD-ACL).

METHODS

Three databases MEDLINE, PubMed and EMBASE were searched from inception to January 29th, 2023 for literature outlining clinical outcomes for various management strategies of MD-ACL. The authors adhered to the PRISMA and R-AMSTAR guidelines as well as the Cochrane Handbook for Systematic Reviews of Interventions. Data on satisfaction scores, visual analogue scale (VAS) scores, Lysholm scores, International Knee Documentation Committee (IKDC) scores, Knee Osteoarthritis and Outcome Scores (KOOS), range of motion and Lachman test were recorded.

RESULTS

A total of 14 studies comprising 776 patients (782 knees) were included in this review. Partial debridement was reported in ten (71.4%) studies comprising 446 patients, showing significant improvements in VAS, Lysholm, IKDC scores and range of motion. Complete debridement was reported by two (14.2%) studies comprising 250 patients, and resulted in increases in Lysholm scores, KOOS, and range of motion. Reduction plasty was reported in two (14.2%) studies comprising 26 patients and showed improvements in VAS and Lysholm scores, and range of motion. Other methods of treatment included conservative management and ultrasound decompression. Complete debridement resulted in 10/23 (43%) patients with a positive Lachman test. This was followed by reduction plasty and partial debridement, with 5/26 (19.2%) and 45/340 (13.2%) patients respectively having positive Lachman or elevated knee arthrometer scores. Pivot shifting was only reported in studies on partial debridement and reduction plasty, with 14/93 (15.1%) and 1/21 (4.8%) patients have positive results, respectively.

CONCLUSION

The most commonly reported management strategy for MD-ACL is partial debridement with complete debridement, reduction plasty and conservative management as alternative options. Current operative management strategies place individuals at risk for ACL insufficiency. Information from this review can aid surgeons and clinicians in understanding what treatment options are best for this patient population, by understanding the reported clinical benefits and risks of each strategy.

LEVEL OF EVIDENCE

IV.

ACL Mucoid Degeneration-Anterior and Posterior Arthroscopic Decompression for Combined Knee Flexion-Extension Deficit

Mucoid degeneration of the ACL (MDACL, ACL ganglion cysts) is a disease involving ACL thickening due to accumulation of mucoid substance and fiber degeneration with possible formation of "ganglions". Clinically, it leads to anteroposterior impingement and painful limitation of knee range of motion due to impingement of the anterior portion of the thickened ACL with the intercondylar notch during knee extension and the thickened posterior part of the ligament with posterior structures of the knee in flexion. Different treatment methods have been described, including total or partial resection of the ACL degenerative fibers. However, these techniques do not allow for ACL preservation and are associated with a risk of postoperative instability. Also, most procedures treat anterior impingement only. Therefore, the aim of this technical note is to present an arthroscopic technique allowing for minimally invasive anteroposterior ACL decompression. The technique is focused on evacuation of the interfibrous mucoid substance, ganglions, and bony decompression, as well as maintenance of ligament integrity. Its greatest advantage is that it is safe and ACL-preserving yet allows for comprehensive treatment of all intra- and extra-ligamentous possible reasons of MDACL origin and promoting good healing conditions.

Symptomatic ACL mucoid degeneration in middle-age athletes

Background

Mucoid degeneration of the anterior cruciate ligament (ACL) is an uncommon non-traumatic cause of knee pain and motion restriction, typically seen in a middle-aged population. Primarily, the management consists of partial arthroscopic debridement and notchplasty, which has proven satisfactory clinical and functional outcomes.

Study objectives

This review aims to highlight key clinical, radiological and arthroscopic findings of mucoid ACL degeneration, and also to provide an approach to manage a symptomatic middle-aged athlete.

Rationale

Due to the paucity of literature on ACL mucoid degeneration, symptomatic presentation in a middle-aged athlete can be challenging to manage. Diffuse central pain, motion restriction in extension or flexion, absence of trauma, and an intact enlarged ACL on Magnetic resonance imaging (MRI) should raise suspicion for mucoid degeneration in middle-aged athletes. Specific radiological and arthroscopic findings can help to confirm the diagnosis. In this review article, we have also described a new clinical test to mimic the pain due to anterior impingement in the presence of an enlarged ACL.

Conclusion

In symptomatic middle-aged athletes, knowledge of characteristic findings can help in the timely diagnosis of mucoid degeneration of ACL. Treatment options include arthroscopic debridement, notchplasty, ACL augmentation, and ACL reconstruction. The presence of associated injuries can influence return-to-sports prognosis.