Medial Meniscus Posterior Root Tear: A Comprehensive Review

Abstract

Damage to the medial meniscus root, for example by a complete radial tear, destroys the ability of the knee to withstand hoop strain, resulting in contact pressure increases and kinematic alterations. For these reasons, several techniques have been developed to repair the medial meniscus posterior root tear (MMPRT), many of which have shown complete healing of the repaired MMPRT. However, efforts to standardize or optimize the treatment for MMPRT are much needed. When planning a surgical intervention for an MMPRT, strict surgical indications regarding the effect of pullout strength on the refixed root, bony degenerative changes, mechanical alignment, and the Kellgren-Lawrence grade should be considered. Although there are several treatment options and controversies, the current trend is to repair the MMPRT using various techniques including suture anchors and pullout sutures if the patient meets the indications. However, there are still debates on the restoration of hoop tension and prevention of arthritis after repair and further biomechanical and clinical studies should be conducted in the future. The aim of this article was to review and summarize the recent literature regarding various diagnosis and treatment strategies of MMPRT, especially focusing on conflict issues including whether repair techniques can restore the main function of normal meniscus and which is the best suture technique to repair the MMPRT. The authors attempted to provide a comprehensive review of previous studies ranging from basic science to current surgical techniques.

Arthroscopic Transtibial Pullout Repair for Posterior Medial Meniscus Root Tears: A Systematic Review of Clinical, Radiographic, and Second-Look Arthroscopic Results

“…Although surgical repair is currently seen as the treatment method of choice for PMMRTs, 3,36,37 the extra effort associated with this procedure requires justification from convincing outcomes. Regarding functional outcome scores, this systematic review shows a consistent and significant improvement in all scores used.…”

“…3,36 Moon et al 30 analyzed prognostic factors of ATPR for PMMRTs in 51 patients and found that varus alignment of more than 5 and Outerbridge grade 3 or 4 chondral lesions were independent risk factors for poor clinical outcomes. Although indications and contraindications were only infrequently reported in the studies included in our systematic review, there is a broad consensus that root repair is only indicated in patients with no or only mild pre-existing OA (Kellgren-Lawrence grade I or II), good tissue quality of the meniscus, and willingness to follow a partial weight-bearing protocol for more than 6 weeks.…”

“…Although indications and contraindications were only infrequently reported in the studies included in our systematic review, there is a broad consensus that root repair is only indicated in patients with no or only mild pre-existing OA (Kellgren-Lawrence grade I or II), good tissue quality of the meniscus, and willingness to follow a partial weight-bearing protocol for more than 6 weeks. 9,19,21,24,31,36 Accepted contraindications include diffuse grade 3 and 4 chondral lesions, uncorrected varus malalignment, root tears with definitive meniscal degeneration, and obesity with a body mass index greater than 30. 3,9,19,21,30,31,37 No definitive consensus exists on the tolerable amount of preoperative meniscal extrusion and varus malalignment or age limit.…”

“…Interest in the treatment of PMMRTs has increased in recent years. 3,36,37 Although arthroscopic partial meniscectomy has been shown to provide moderate symptom relief in most patients with PMMRTs, it cannot restore the function of the meniscus and is MRI, magnetic resonance imaging; NR, not reported. *Lax healing, scar tissue healing, and loose healing were regarded as partial healing.…”

Meniscal root tears: a silent epidemic

“…The most common presenting symptoms in meniscal root tears are posterior knee pain and joint line tenderness, especially with deep squatting 46. Another common symptom is a popping sound that is heard while participating in light activities, like ascending stairs or squatting 47. Seil et al 48 described a test that has proven useful in diagnosing a medial meniscal root tear.…”