What is “MIS” Joint Replacement Surgery?

Fig 1: X-Ray of Right Hip Osteoarthritis Pre-OP
Fig 1: X-Ray of Right Hip Osteoarthritis Pre-OP

MIS stands for “Minimally Invasive Surgery.” The objective of MIS surgery is to allow for faster recovery, and the ability to return to normal activities quicker. This is accomplished through smaller and less painful incisions. Recent technological advances in implants and instruments used in performing the surgery have allowed for the development of MIS procedures.

In recent history, MIS surgery has evolved to encompass a wider array of procedures and meanings. In my application of the term, and in modern day practice, a more appropriate phrase is “MSS” otherwise known as “muscle-sparing surgery.” In this technique the surgical approach is performed through a region of the body where no muscles or tendons need to be cut or separated from the bone. This approach has led to faster recovery and improved patient satisfaction. The MSS technique is utilized in both hip and knee replacement surgery.

Fig 2: X-Ray of Right Total Hip Replacement through Direct Anterior Approach
Fig 2: X-Ray of Right Total Hip Replacement
through Direct Anterior Approach

In hip replacement surgery, the “direct anterior approach” has been a significant advancement in the realm of MSS. A total hip replacement is traditionally performed via a relatively large incision on the back or the side of the hip. The traditional technique requires releasing the muscle tendon which put the patient at risk for dislocation of the joint and/or limp. In the direct anterior approach, a small incision in the front of the hip is utilized. This small incision is strategically placed in front of the hip and allows for muscle sparing. This technique is beneficial to the patient for a multitude of reasons. There is less risk of dislocation of the joint and/or limp. This translates to no range of motion or activity restrictions after the surgery while being able to place full weight on their leg after the surgery. Ultimately the patient benefits as they are able to return to their daily life activities quicker due to being able to rehabilitate faster after surgery.

Hana® Radiolucent Surgical Table
Fig 3: Picture of Hana® Radiolucent Surgical Table

A special surgical table is utilized during the direct anterior approach. X-ray imaging during the surgery allows for the surgeon to accurately reconstruct the patient’s natural anatomy by making changes where necessary with the implant size and position. The end result produces a more natural feeling hip after the surgery. Finally, the orientation and size of the surgical incision are cosmetically appealing with the added benefit of being less painful.

For knee replacements, there are also muscle sparing techniques. The quadriceps is one of the integral muscles of the thigh needed for extending the knee and ambulation. The “sub-vastus approach” is one where a total knee replacement can be performed without having to cut any muscles or tendons. In this approach, the quadriceps muscle and tendon are moved to the side to allow the replacement to be performed. Post-operatively this allows a faster and improved recovery.

However, MSS total hip and knee replacement is not for everyone. Certain body types and pathology might not be appropriate for these techniques. If you are experiencing arthritis symptoms, or are considering a hip or knee replacement, make an appointment with Dr. Stanat who is fellowship trained in adult hip and knee replacement surgery.

Joint Protection Techniques

Arthritis is one of the most prevalent chronic health problems and the nation’s leading cause of disability among American’s over the age of 15. Although this is a staggering statistic, there are some things that can be done to help people with this disease feel more comfortable. Joint protection techniques work best for persons with rheumatoid arthritis but all can benefit from these simple measures to prevent additional stress on your joints.

  • Respect Pain: when you have pain in your joints at best it is important to reduce your activity level and allow inflammatory process to subside.
  • Use the Strongest Joints Available for the Job: Using stronger larger joints for tasks will help prevent pain in smaller affected joints. A simple application is carrying a purse over your shoulder instead of holding it with a hook grasp.
  • Avoid Staying In One Position For Long Periods of Time: when you are in a long position for a long time your muscles become fatigued, once this happens the muscles can no longer hold the joint in a stable position and the load transfers to the joint and its capsule. Changing position and taking breaks along with range of motion exercises can help to prevent muscle fatigue and protect the joint capsule.
  • Balance Rest and Activity: It is important to have fine balance between times of activity and the subsequent rest periods needed to allow the body to recuperate.
  • Maintain Muscle Strength and Joint Range of Motion: Balanced strength around an unstable joint can help reduce the pain and further damage to that joint. Maintaining range of motion is so important because once a joint has reduced motion the surrounding joints, especially distal ones, have to make up for it.
  • Avoid Positions of Deformity: Avoiding forces that put joints in directions of deformity is very important in reducing the chance of pain. Holding a book with your palms while reading instead of pinching it with your thumb and index finger is an example of this.

These are just a few examples of what can be done to help reduce deformity and pain associated with arthritis. If you are affected with arthritis it is important to be seen by a health care professional regularly to monitor the progression of this potentially debilitating disease