Injectable Enzyme Medications
Injectable enzyme medications are a class of medicines that use tiny proteins (called enzymes) used by living organisms to break down other substances. Enzymes are used by many types of organisms, ranging from bacteria all the way to human beings. They each have a particular job, such as digesting food, metabolizing medications, and absorbing vitamins and nutrients. Scientists have long studied these proteins to understand bodily functions, and have deciphered the chemical structure of many particular enzyme proteins. Other scientists were then able to manufacture some of these same proteins in a lab and make them into an injectable form. This technology has allowed patients with enzyme deficiencies to regain missing functions. Recently, doctors and pharmacists started looking at using naturally-occurring enzymes for jobs other than their native function. The streptokinase enzyme has been harnessed and used to break down blood clots in important blood vessels, such as to treat stroke patients. Hyaluronidase is an enzyme that breaks down hyaluronic acid outside cells and can now be used to increase the absorption of other medications, including insulin.
Dupuytren’s Disease Injection and Manipulation Procedures
Traditionally, Dupuytren’s disease was treated with surgery to cut out the abnormal tissue and allow the finger(s) to straighten out. This procedure involves fairly large incision(s) on the palm of the hand and is usually done under general anesthesia because the nerves and blood vessels of the hand can be intertwined with the Dupuytren’s tissue, requiring the patient to be perfectly still during the surgery. Because Dupuytren’s patients are often elderly and sometimes have other medical conditions, surgery under general anesthesia may not always be a good option. As such, doctors have long looked for less invasive ways to treat this condition. The question was asked: “What if, instead of cutting out the Dupuytren’s cord, we could just rupture it and then manually straighten the finger back out?”. This led to research into possible ways to rupture the cords of Dupuytren’s tissue. Percutaneous needle fasciotomy/ aponeurotomy involves using a needle to basically saw through the thick tissue in the cord and rupture it. Injectable enzyme treatment involves placing a collagenase enzyme into the tissue of the cord to weaken the tissue and lead to the rupture of the cord.
As mentioned above, Dupuytren’s disease has been traditionally approached with open surgery to excise as much of the abnormal Dupuytren’s tissue as possible, while leaving behind tendons, nerves, blood vessels, and other normal structures. Upon removal of the cord, the affected finger(s) can be manually extended during the surgical procedure. The surgeon then makes sure bleeding is controlled and closes the skin. The hand is inspected to make sure there is good circulation and a bandage and splint are then applied. The patient then wakes up and goes home that same day, usually with a pain prescription. Typical challenges with partial palmar fasciectomy surgery involve patient factors that make anesthesia challenging, and also occasional problems with wound healing after the procedure. Success in correcting joint contractures is the highest with open surgery, and is seen in up to 90% of treated joints. Recurrence is still a problem and occurs in about a third of patients by five years. Complications with open surgery are still uncommon, but can be more severe, including damage to the nerves and blood vessels of the fingers. These are more common in severe disease or during repeat surgery, with rates up to 15% in these situations.
Instead of open surgery, a large bore needle can be used to disrupt the cord. With this in-office procedure, the surgeon cleans the hand, injects local numbing medication with a small needle, and then uses a larger needle in a back-and-forth sawing fashion to divide the Dupuytren’s cord. After the cord has been divided into two pieces, the surgeon applies force to the affected finger(s) to extend the finger(s). The hand is then bandaged, placed in a splint, and the patient is sent home the same day, possibly with a small
number of pain pills. Success rates have been documented to be similar to those of Xiaflex®, while recurrence rates are the highest (and happen the soonest) with this procedure. Complications are rare with this procedure.
Dupuytren’s disease (also called Dupuytren’s contracture or palmar fibromatosis) is a condition that affects the tissue under the skin of the palms of the hand. This tissue, called the palmar fascia, is normal tissue, but it becomes abnormal. In this condition, the tissue becomes thick and tough, turning into a band or cord that actually starts pulling one or more fingers down into a flexed position. This can affect one or more digits and can be present on one or both hands. Some patients have similar conditions on the sole of the foot and on the penis. Dupuytren’s is more common in men than women, in certain ethnic groups, and in concert with certain medical conditions. In fact, the historic predilection of this condition amongst Northern European men led to the nickname ‘Viking’s disease’. Dupuytren’s can run in families and is at least partially genetic. While it is not cancerous or invasive, sometimes the abnormal tissue becomes a problem anyway. Over time, the fingers can get pulled down into a bent position and become stuck that way. This can lead to problems using the hand for activities and even putting the hand in a pocket. Patients often seek treatment from a hand surgeon for Dupuytren’s disease
Xiaflex® is an injectable form of the collagenase enzyme used by clostridium bacteria to digest collagen. When injected into a Dupuytren’s cord, the enzyme dissolves the collagen fibrils at the site of injection. This creates a weak spot in the cord, such that it either ruptures on its own, or is easily ruptured by the physician at a subsequent doctor visit. Collagen is also present in many other important structures of the hand, including the tendons that move our fingers, so it is important that trained professionals inject it directly into the cord, and not anywhere else. Success after an injection procedure has been defined as correction of the joint contracture to 5 degrees or less. While these rates vary according to how severe the contracture was beforehand, 50-75% of joints were treated successfully in the large CORD I and II trials. Recurrence of joint contractures seems to happen with any treatment, and has been observed in roughly half of Xiaflex patients within five years of treatment. Complications of Xiaflex injection most often include pain and swelling, as well as minor skin tears, and very rarely include more severe inflammatory reactions, and damage to the tendons or other structures in the hand.