Discoid lateral meniscus: current concepts.

Area of Science:

• Orthopedics
• Sports Medicine
• Anatomy

Background:

• The discoid meniscus is a congenital morphological abnormality, most commonly affecting the lateral side (discoid lateral meniscus, DLM).
• DLM prevalence varies globally, being higher in Asia (10%-13%) than in Western countries (3%-5%), and often occurs bilaterally (over 80% of cases).
• Its abnormal shape predisposes it to tearing and can affect gait mechanics, with potential implications for healing due to altered collagen and vascularity.

Purpose of the Study:

• To review the characteristics, presentation, and management of discoid meniscus.
• To compare surgical outcomes for discoid meniscus repair versus meniscectomy.
• To identify factors influencing prognosis in discoid meniscus treatment.

Main Methods:

• Literature review of discoid meniscus morphology, prevalence, and clinical presentation.
• Analysis of surgical techniques including saucerisation, repair, and meniscectomy.
• Evaluation of functional outcomes, arthritis onset, and prognostic factors based on existing studies.

Main Results:

• Symptomatic DLM presents with mechanical knee complaints like locking, clicking, or pain, often due to tears or peripheral detachments.
• Conservative management is suitable for asymptomatic or non-locking symptomatic cases; peripheral detachments require stabilization.
• Long-term functional outcomes and reduced arthritis incidence favor saucerisation and repair over subtotal meniscectomy, though repair evidence is not definitive.

Conclusions:

• Discoid meniscus management depends on symptoms, with repair potentially offering better long-term results than meniscectomy.
• Preserving the meniscus rim is crucial for stability when addressing peripheral detachments.
• Prognosis is poorer with total meniscectomy, older age at presentation, and valgus malalignment.