Common Knee Injuries: Cartilage Damage and Meniscal Tears
Knee injuries and dysfunction are some of the most common reasons patients seek orthopaedic care. Up to 50 million people are affected with arthritis in the United States, with the knee being a primary focus. What symptoms and signs are associated with significant knee injuries, and when is surgical treatment a reasonable consideration?
There are two types of cartilage in the knee. The articular cartilage (white smooth cartilage which covers the end of the bone – like the white on the end of a chicken bone) and the meniscus (C-shaped cushions between the femur and tibia which act as shock-absorbers). These structures can be injured through trauma or can progressively degenerate through the stress of life. Age, activity level, and symptoms associated with the injury determine appropriate treatment.
In young athletes, meniscal and articular cartilage injuries generally require surgical treatment for optimal function. Knee arthroscopy, a minimally-invasive procedure where a 4mm camera is used to visualize the damage and special instruments are used to either repair or sculpt the injured tissues, leads to rapid recovery in most cases. Athletes can return to play as soon as two weeks after this procedure.
For middle-aged and more senior athletes, treatment is generally dictated by the extent of underlying arthritis and pre-existing activity level. Mechanical symptoms (locking and catching) generally indicate an anatomic issue that may be improved with arthroscopic treatment. On the other hand, insidious onset of activity-related pain without mechanical symptoms is more characteristic of articular cartilage wear – arthritis. Articular cartilage wear is an inevitable part of aging, and individuals experience this at different rates. For the 60-year old runner with new-onset mechanical symptoms after an injury and no significant evidence of arthritis on knee xrays, knee arthroscopy is indicated and highly effective. On the other hand, the younger patient with xrays showing significant loss of joint space – indicating long-term articular cartilage and meniscal wear – is less likely to benefit from this intervention. Other non-operative interventions such as physical therapy, bracing, anti-inflammatory medication, cortisone and or hyaluronic acid (Synvisc, etc) injections may be the better course of action. The key here is determining whether your symptoms are mechanical – indicating a piece of loose or torn cartilage that can be fixed with an arthroscopic procedure – or resulting from underlying articular cartilage wear. Unfortunately, the reported results of knee arthroscopy for treatment of arthritis are not good. A good point to remember is that approximately 50% of asymptomatic people between the age of 40-50 will have a meniscal tear on MRI, but Do Not Need Surgery. Other options, such as cartilage resurfacing procedures (“cartilage transplants”) have limited indications for specific anatomical issues, and should not be used in patients with more generalized arthritic change. Stem cells interventions have had consistently inconsistent results in arthritic intervention studies, are very costly, and are not covered by insurance plans. Hopefully future applications will be able to demonstrate results that merit the cost of these procedures. Other surgical interventions – partial or total knee replacement or osteotomy – provide excellent results in terms of pain relief and improvement in function for people with debilitating knee arthritis.
Your orthopaedic surgeon should be able to help guide you through which of these options is best in your specific situation, and have the technical expertise to perform any of the above interventions when indicated. More importantly, he or she should help you decide which of the available options has the best risk to benefit ratio for you – optimizing function while avoiding unnecessary surgery or cost.
If you would like to me to provide you with a personal consultation, please contact my office for I would be happy to meet you.
Dr Robert S Wolf