Arthroscopic surgical techniques are utilized for a variety of knee injuries. One of the most common injuries to the knee is a torn anterior cruciate ligament (ACL). The ACL is a stabilizing ligament located deep inside the knee joint. Injuries to the ACL generally occur as a result of a hyperextension or severe rotational force on the knee, causing the ACL to tear to varying degrees.
If the ACL is only partially torn or demonstrates significant laxity, the ACL may simply be shrunk to help tighten the ligament. This technique is performed arthroscopically with minimal incisions. In most cases, the surgery reduces the ligament laxity by 50% or more. This is a good alternative for patients who are not obvious candidates for full reconstruction surgery.
Arthroscopic reconstruction may be required to repair a significantly torn ACL. If the ACL is no longer intact, a new ligament must be created. This is accomplished using three common methods. The first method is called an autograft. In this case, the surgeon takes a strip of tendon from the patient, typically the patella tendon, to reconstruct the ACL. This is the most widely used method and the method of choice for most surgeons. The second method involves harvesting a hamstring tendon to reconstruct the ACL. This method is used for patients who are not patella tendon candidates. The final method uses an allograft, which is tissue taken from a donor. This option is used in cases where multiple ligaments have been damaged or where a previous patella tendon reconstruction has failed.
Most arthroscopic reconstruction surgeries last between 2-3 hours and require 1-2 hours of recovery time, after which the patient goes home. Depending on the severity of the injury, patients can expect to regain most normal function in 4-6 weeks for a patella tendon reconstruction, and 12 weeks for a hamstring and allograft reconstruction.
At one time, arthritis of the knee resulting from osteoarthritis and post-traumatic arthritis was seen more commonly in men. The latter diagnosis was seen in men who had experienced an injury such as a torn anterior cruciate ligament or a torn meniscus, and who, even with appropriate treatment, eventually developed arthritis in the joint. Today, with greater participation by women in a range of recreational and sports activities, that trend has changed and arthritis of the knee arising from these conditions is seen about equally among the sexes. Arthritis of the knee that is associated with rheumatoid arthritis is seen more commonly in women.
Gender can also play a role in the specific area of the knee in which the arthritis develops, with women because of their wider pelvic structure being more likely to develop erosion on the “outer” portion of the knee resulting in a valgus deformity. This is manifest as a knock-kneed stance. People with arthritis of the inside portion of the knee develop a varus deformity and tend to have a bow-legged stance. Some evidence suggests that genetics may also determine the type of arthritis that develops. In Japan, for example, arthritis of the knee is almost exclusively varus.
Surgical treatment options for arthritis of the knee include osteotomy (in which the bone is cut to realign the joint). Depending on the extent of the arthritis, some patients may be eligible for a unicompartmental surgery in which only one part of the joint is replaced. In addition, for patients with arthritis in both knees, TKA in both joints in a single procedure is an option.
Key to the success of these procedures is surgical technique and the selection of the appropriate prosthesis. Orthopedic surgeons determine the latter based on the patients age and lifestyle. In addition to relieving pain and disability, the goal of an Osteotomy is to restore range of motion, which is measured in degrees. Generally, a reasonable expectation is to regain the same range of motion the patient had prior to surgery, with the high end of the range being about 120 degrees. Patient adherence to a well-designed rehabilitation program also plays an important role in determining outcome. Many individuals find the use of continuous passive motion (CPM) machine equipment that moves the patient’s knee through a range of motion to be particularly helpful.
Non-surgical Treatment of Arthritis
Fortunately, a range of non-surgical and surgical options are available to treat all patients with arthritis of the knee. Non-surgical treatment includes the use of NSAIDs (non-steroidal anti-inflammatory drugs) such as ibuprofen and naprosyn, as well as a newer class of agents called the Cox-2 inhibitors for reduction of inflammation and pain relief. Injection with steroids can offer temporary, symptomatic relief, but are not generally recommended for prolonged use.
Visco-supplementation involves injection of a viscous substance that resembles the synovial fluid normally found in the joints. This therapy also offers temporary relief of symptoms in some patients, but repeated injections are required. Some patients also report relief of symptoms after taking glucosamine and chondroitin supplements, however there is not a good body of scientific evidence to establish their efficacy and the FDA does not regulate their use.
In addition to these treatments, patients are often advised to modify their activities, and when appropriate, to lose weight to reduce stress on the joint. Physical therapy can offer considerable relief as well. As the patient strengthens the muscles that surround and support the knee, the stress on the joint is reduced, as is associated pain.
Use of a cane or unloader braces (which literally reduces the stress load on the joint) may also help some patients.