How do horizontal cleavage tears happen?
The internal shearing of a horizontal cleavage tear may occur in a normal knee if there is a very strong twisting force.
However, more often the meniscus is already degenerative from previous trauma, and twisting just makes this worse.
"...Such scenarios include positions with increased degrees of closed kinetic chain flexion (kneeling, squatting), lifting/carrying heavyweights, and activities requiring rapid acceleration/deceleration, change of direction, and jumping...."
Management of horizontal cleavage tears
Horizontal cleavage tears are difficult to manage.
Surgeons will often choose a partial meniscectomy or even a total meniscectomy, preserving what they can of the rim. Repair might be attempted after roughening up the inside of the tear, pushing a lump of blood clot (from the patient) into the defect, and suturing it in place.
"...these tears have traditionally been treated with partial or total menisectomy. Growing evidence supporting the role of the meniscus in knee stability, load distribution, and arthritis prevention has led to an increased effort for meniscal preservation."
"Healing.... is highly dependent on stability of the repair, compression across the defect, and vascular supply to the repair site....Circumferential compression using an all-inside self-retrieving suture-based device allows for uniform compression....and facilitates a stable, anatomic repair....microfracture....in the lateral aspect of the intercondylar notch....allow[s] for bone marrow elements to leak into the joint space"
Horizontal cleavage tears and meniscal cysts
The clam-like nature of horizontal cleavage tears may allow fluid to be forced out into the tissues on the side of the joint, forming a new problem - a meniscal cyst - a tender, palpable, fluid-filled lump in the joint line.
"...meniscal cysts can be successfully managed arthroscopically with cyst decompression, excision, and/or percutaneous decompression with arthroscopic visualization."
Video
This video shows a horizontal cleavage tear seen at surgery through an arthroscope.
The surgeon is probing the horizontal tear of the meniscus to see how deep it is.
Video courtesy of Dr Ram Venkatesh
Other relevant links -
Degenerate meniscus, Closed chain, Partial meniscectomy, Total meniscectomy, Meniscal repair, Meniscal repair augmentation, Meniscal cyst, Pain in the back of the knee, Radial tear, Longitudinal tear, Bucket-handle tear, Horizontal cleavage tear, Parrot-beak tear, Flap tear, Ramp lesion
Forum discussions
- What does this mean? Help. Do i need an op? - Doctor's report causes confusion regarding a cleavage tear.
- Lateral Meniscal Cyst but MRI shows no tear...help or advice please ?!?!?! - Brief discussion about meniscal cyst being associated with horizontal cleavage tears.