PARTIAL KNEE MENISCECTOMIES LINKED TO OSTEOARTHRITIS
                     PARTIAL KNEE 
MENISCECTOMIES 
LINKED TO 
OSTEOARTHRITIS
http://www.virtualphysicaltherapists.com/
A meniscal tear is one of the most common sports-related knee injuries in the United States. Traumatic 
tears in young athletes and middle-aged weekend warriors are usually treated surgically, even though 
beneficial evidence from clinical trials is lacking. Instead, research has shown that total and partial-knee 
meniscectomies are linked to early osteoarthritis. 6, 7, 34
Arthroscopic partial meniscectomy
Arthroscopic partial meniscectomy is the most frequently performed orthopedic surgery in the world. 
Approximately 500,000 are performed each year in the USA, 40% of whom are patients under 45 years 
old. The concern is that long-term outcomes have shown an increase in developing osteoarthritis 
compared to non-surgical counterparts.
Research as far back as 1948 revealed that the removal of the meniscus results in early osteoarthritis. 
Eventhough the vitality of the meniscus was well-known 80 years ago, surgeons still routinely removed it. 
In the 80’s and early 90’s many young adults found themselves requiring a full knee replacement 20 years 
after knee surgery. 
Arthroscopic allowed a less-invasive procedure and surgeons then changed to only partial removal of the 
meniscus attempting to maintain as much as they could. For years, arthroscopic knee surgery was shown 
to have positive early and long-term outcomes. But surgery was rarely compared to sham surgery or 
conservative care/physical therapy. Today, meniscus surgery aims to preserve as much tissue as possible. 
Only recently has research looked at the outcomes of partial meniscectomy to sham surgery or 
conservative care/ physical therapy. But compared to conservative care, the risk of arthritis is still found 
more significant in the surgical group.
Knee Anatomy & Causes of Knee Pain
 
Meniscal Anatomy:
The meniscus is fibrous cartilage or a cushion between the upper femur and the lower tibia bone. It is 
divided into three zones based on the degree of vascularization. The thickest outer region, known as the 
‘red zone’ is highly vascularized, while the inner central region is very thin. Due to the vascularization or 
blood supply, the red zone is enriched in nutrients that enable self-healing. 
The inner (middle) region is referred to as the red-white zone, which contains less vascularization than 
the red-red zone and has minimal self-healing capacity. The innermost region of the meniscus is 
completely devoid of blood supply and appears to lack the ability to self-repair. Meniscus tears are a 
particular risk for older athletes since the meniscus weakens with age. More than 40% of people 65 or 
older have them.
The anterior horn of the medial meniscus attaches near the anterior cruciate ligament (ACL) on the tibia, 
whereas the posterior horn attaches above the posterior cruciate ligament (PCL). It is very common to 
have a meniscal injury when the ACL or PCL ligaments are torn.
Knee Meniscal Injury
The most common injury to the knee is a tear in the meniscus. Any activity that causes you to twist or 
rotate your knee forcefully can lead to a tear in the meniscus, especially when putting your full weight on 
it. Sometimes, a piece of the shredded cartilage breaks loose and catches in the knee joint, causing it to 
lock up. The meniscus performs vital functions of shock absorption and provides mechanical stability and 
lubrication to the knee joint. Unlike articular cartilage or coverings on the outside of the bones, the 
menisci are soft t and kept in place by ligamentous attachments, allowing them to slide during knee 
bending and straightening. 
Shock absorption or protecting the knee from wear and tear is the primary function of the meniscus. 
When the meniscus is reduced due to surgical resection, the load distribution is thrown off, causing an 
increased force on the articular cartilage during weight-bearing. This interferes with shock absorption, 
which can lead to breakdown and eventually leads to osteoarthritis. This is why even partial knee 
meniscectomies are linked to early osteoarthritis.
 
Symptoms
When you injure your meniscus, it usually takes 24 hours for your knee to swell and become painful. The 
following are common signs and symptoms of a torn meniscus:
· Swelling and stiffness
· A popping sensation
· Pain, especially when twisting or rotating your knee
· Inability to fully squat on the involved leg
· Difficulty straightening your knee fully
· Feeling as though your knee is locked in place when you try to move it
· Feeling of your knee giving way
Conservative treatment 
The body has a miraculous way of healing itself. The role of your clinician is to educate each patient on 
the best movements and activities that enhance healing. The goal is to fully recover from a knee injury 
as fast as possible, return to our sport and full activity and prevent future arthritis.
Knee Treatment for the inflammatory stage: 
RICE  (rest, ice, compression, elevation)
During the acute/inflammatory stage of healing, RICE (Rest, Ice, Compression, Elevation) is the 
treatment protocol. Rest depends on the severity of the injury. Fractures and significant inflammation 
would require complete rest. But most knee injuries require “active rest” or continuing with light 
activity within tolerance to prevent muscle wasting and poor healing of tendons.
Derangement – A problem within the joint secondary to a meniscal tear
Joints have cartilage protecting the outer layer of bone and an extra buffer between the bones. In the 
knee, this cushion is known as the meniscus. Repetitive motion strains the joint, especially if the 
movement is awkward or has poor mechanics. 
This strain can cause microscopic tears in the cartilage and even cause a tiny piece of your cartilage to 
break off. This is part of the natural wear and tear process, but excessive activity combined with poor 
mechanics will advance this breakdown, known as a “derangement.” Even though this broken piece is 
tiny, it can cause pain and loss of motion if it interferes with the joint’s smooth mobility. Derangements 
are characterized by intermittent pain, pain during movement, and a loss of motion (can be constant 
pain if a joint is held in an abnormal position, such as a dislocation).
Knee Treatment for Derangements:  Reduction of derangement, Regain full range of motion, Progress 
to the recovery of function.
Research: Partial Knee Meniscectomies Linked to Early Osteoarthritis
A recent randomized controlled study just published a few months ago compared partial 
meniscectomies in young patients (aged 18-45 years) to physical therapy and the option to delay 
surgery. Most studies prior were not randomly controlled. At 24 months, there was no difference 
between physical therapy and arthroscopic partial meniscectomy. 59% of randomized patients to PT did 
not undergo delayed arthroscopic surgery. They concluded that physical therapy should be an 
alternative to early arthroscopic surgery.
7
Another study out just this month tracked the prevalence of osteoarthritis between 5 and 15 years after 
arthroscopic partial meniscectomy. Arthritis was found in 23-100% across all periods with increased 
rates between 10-15 years. They also found that the uninjured knee had a higher rate of osteoarthritis 
and theorized that arthroscopic surgery might lead to bilateral maladaptive movement patterns, 
potentially affecting the uninjured knee.
Additional studies questioning the value and frequency of arthroscopic partial meniscectomies in favor 
of conservative care:
2020 Sihvonen et al. (BJSM)
Five-year follow-up found that arthroscopic partial meniscectomy was not superior to placebo surgery, 
and there is a 13% increased risk of progression of knee osteoarthritis.
2019 Katz et al (Arthritis Rheum)
Five-year outcome of operative and nonoperative management of meniscal tear in persons older than 
forty-five years: Pain improved in both groups with no significant difference, but the operative group 
had a greater frequency of total knee replacement surgery.
8
2017 Beaufils & Pujol. Elsevier
A literature review concluded that a paradigm shift is needed in favor of meniscal preservation. 
Meniscectomy should no longer be the first-line option.
2016 Kise et al. (BMJ)
Exercise therapy versus arthroscopic partial meniscectomy for degenerative meniscal tear in middle-
aged patients: a randomized controlled trial with two-year follow-up. No difference was found, and the 
PT group showed greater quadriceps strength.
2015 Hulet et al (Knee Surg Sports TraumatolArthrosc)
At 20 years follow-up, 56% osteoarthritis was found following lateral meniscectomy. 
2013 Sihvonen et al. (N Engl J Med)
146 patients with a degenerative meniscus tear and no evidence of OA were randomized into 
arthroscopic partial meniscectomy or a sham surgery group. The outcomes after arthroscopic partial 
meniscectomy were no better than those that underwent a sham surgical procedure.
9
1998 Charrois, Ayral & Beaufils (Revue de Chirurgie Orthopedique et Reparatrice de L’appareil Moteur)
The authors noted that osteoarthritis is common following meniscectomy. In a multicenter study by the 
French Arthroscopy Society, joint line narrowing was 22% in the medial meniscus and 40% in the lateral 
meniscus at a mean of 13 years follow-up. 
1995 Rangger, Klestil & Gloetzer AJSM 
Partial medial or lateral meniscectomy leads to a significant increase in osteoarthritic changes, even 
when performed arthroscopically.
(Badlani et al., 2013; Chang and Brophy, 2020; Rai et al., 2020; Adams et al., 2021; Bedrin et al., 2021). 
The moral is don’t rush in to have surgery. Give your body a chance to do what it knows best – heal. 
Your body’s ability to heal is miraculous and way ahead of our current technological ability. Seek medical 
treatment based on conservative care that empowers healing, educating you on the best practices to 
enhance your body’s ability to heal itself. If after you have exhausted conservative care, only then should 
you consider surgery. But remember partial knee meniscectomies are linked to early osteoarthritis.
10
VIRTUAL 
PHYSICAL 
THERAPISTS
[email protected]
HTTP://WWW.VIRTUALPHYSICALTHERAPISTS.COM/
1
1