Bone Talk

The gospel proverb- "Then shall the lame leap" applies aptly to the advent of Orthopedic surgery two centuries ago. Orthopedics: the care of bones and joints which enabled the little Forrest Gump to get up, to stand and to leap, has indeed improved the lives of many. Let's take a journey through the lens of history to examine the contribution this field has made to the well-being of human kind.

by Linglei (Leslie) Xu

Bones of the past...
    The pioneer of orthopedics was Nicolas Andry. Andry, a prominent physician and professor of Medicine at the Royal College of Physicians at Paris, had a special interest in correcting deformities in children, advocating the use of splints while avoiding the use of surgery. He derived the word orthopedic from the Greek roots "orthos"(straight) and "pais"(a child). He was also the first one to apply this word to the art of correcting deformities. In his book, Orthopaedia: Or the Art of Correcting and Preventing Deformities in Children: By such Means, as may easily be put in Practice by Parents themselves, and all such as are Employed in Educating Children (1741), Andry suggested many postural exercises to correct deformities-in one case, an adolescent girl straightened her bent spine by carrying a weight in one arm.

    During Andry's time, orthopedic and other varieties of surgery were not advocated due to the lack of essential tools that we now take for granted-anesthesia, asepsis, X-rays, CT scans, and electron microscopes. Surgical operations that required more than a few minutes to perform were out of the question when the patient's consciousness could only be clouded by intoxication, namely, by drinking alcohol. Due to lack of sterile techniques, major operations often failed because they were inevitably followed by infections incurred during surgery. Doctors did not even know what substance or organism caused infections and were unable to prevent or cure them. Because of the high mortality associated with surgery, it was rarely advised except in life or death situations.

    Orthopedics and surgery would not long stay separated, however. Later in the 18th century, John Hunter, now considered the father of modern surgery, brought along literally thousands of dissections and countless scientific experiments to revolutionize the field. In one of his experiments, Hunter marked two points in a growing pig's bone and later found them to be the same distance apart in the mature animal. He thus showed that bones grow in length only at their ends. Surgery established by Hunter became a scientific discipline instead of the hit-and-miss experiments performed during Nicolas Andry's time.

    Surgery made further critical advances in the 19th century. The discovery of anesthesia by Crawford Long in 1842 and W.T.G. Morton in 1846 gave doctors greater freedom to put their new anatomical knowledge to practical use. After Louis Pasteur discovered that microorganisms caused infections, Joseph Lister (1827-1912), a young Scottish surgeon, realized that antiseptic surgical techniques would allow surgeons to suture wounds and avoid infection. Finally, Roentgen reported his discovery of X-rays (or roentgenograms) in 1895, which was immediately put to practical use in surgical diagnosis. Fractures, bone diseases, tumors, arthritis, loose bodies and calcification could all be detected via X-ray diagnosis.

    After these advances, Hugh Owen Thomas, son of a simple Welsh bone setter, blended his father's bone setting skills into the field of medicine and devised new methods of examining joints. These methods came at a critical time as the number of injuries skyrocketed due to the atrocious working conditions of the Industrial Revolution. The Thomas Test, for example, demonstrated the need to keep the spine flat on the bed when examining for hip deformity. He also devised the famous Thomas splint to keep the fractured limbs still. For inflamed joints, he made splints that kept the limbs motionless while allowing the patient to walk.

    Thomas had pupils from all over Britain and US, one being his nephew Robert Jones. Jones absorbed Thomas¹ principles and spread them throughout the British Commonwealth and the U.S. in a great upsurge of orthopedic care to the wounded of World War I. The Great War thus marked the beginning of orthopedic surgery as a separate field apart from general surgery.

Roll the bones: the advent of prosthesis
    Most sophisticated orthopedic surgical procedures such as knee and hip prostheses were not developed until the 70s. Major advances were propelled by the need of knee implants and hip replacements for arthritis patients. Approximately one of every seven individuals in the United States is affected by arthritis and many of these cases involves the knee. Most knee problems are caused by diseases such as rheumatoid arthritis, gout, and infectious arthritis, all quite common. The most common, however, is degenerative osteoarthritis in which the joint is literally worn away by the disease. Therefore, total knee or hip replacements are often necessary. In fact, approximately 70,000 total replacements are performed each year in the US since the 70s. The demand for total replacement operations will likely increase in the next decade.

    There has been much advancement in prostheses in recent years. Several techniques for knee replacement are now available: all of them rely upon replacement of one or both of the articular surfaces by a metal or place (polyethylene) prosthesis. Most of the earlier devices took the form of a hinge, with the upper and lower arms jammed or cemented into the shafts of the femur and tibia respectively. Such devices are still in use, though not extensively. The present trend is to provide gliding articular surfaces rather than a pivoted hinge.

    As in all foreign implants, the surgical success depends greatly on the subject body's response. Some local effects of foreign implants include formation of a fibrous membranes found in the implantation of all materials. The mechanical nature of many prostheses such as wear debris tend to stimulate phagocytic reaction which leads to immune responses. Additionally, the bulk of an implant may cause revascularization of tissues. In choosing among three classes of implant materials, namely metals, ceramics and polymers, one needs to consider properties such as abrasion resistance, coefficient of friction, endurance limit, and the nature and biological effects of degradation products. Prosthetic design involves far more considerations and complicated material choice decisions, but further research will enable us to alleviate as many problems as possible in the future.

    Another important consideration in orthopedic surgery and prosthesis implants is the possibility of infection. Although, surgeons take extraordinary precautions during operations, complications still occur. Infection, an old nemesis, may occur immediately after an operation either from surgery or from bacteria elsewhere in the body. Infection of the knee have been caused by tooth abscesses, dental manipulation, urinary tract infections, or pneumonia. A small percentage of patients will experience loosening of their new joint resulting in pain or progressive deformity. The complications, if left untreated, may necessitate more surgery. Also, human bones, unlike machines, modify and grow after the artificial parts are in place, thereby requiring long-term follow-up of at least six years, according to some doctors.

    Future prospects look promising for the specialty of orthopedic surgery. As the research for low wear polyethylene, higher molecular weight polyethylene, and custom design prosthesis with computer-aided-design goes on, the advances in orthopedic surgery will provide hope to many people with bone deformities and injuries.

Author's Note:
Linglei (Leslie) Xu, a senior in Agricultural & Biological Engineering, hoped to discover the meaning of life at Cornell but ended up with no life at all.