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How To Differentiate And Treat Tendon Pathology
These authors offer diagnostic tips and treatment pearls for lower-extremity tendon injuries, with a specific focus on managing chronic tenosynovitis. Tendon pathology in the foot and ankle are the most common of all injuries. Obviously, there have been chapters in books dedicated solely to repairing individual tendons in the lower extremity. Given the array of external factors (i.e., duration and intensity of activity, improper shoes) and intrinsic factors (i.e., altered body mechanics, advanced age) that can cause tendon pathology, let’s take a closer look at how to differentiate tendon injuries and, in particular, chronic tenosynovitis. In order to effectively understand tendon pathology and chronic tenosynovitis, you should have a strong understanding of the tendon anatomy. Also remember that tendon injuries and pathology can be separated into different classifications. Paratenonitis, which used to be called tenosynovitis or peritendinitis, is an inflammation of the paratenon only, whether or not there is a synovial lining. There is thickening of the paratenon with adherence to the underlying tendon. When your patient has paratenonitis with tendinosis, you’ll see an inflammation of the paratenon associated with degeneration of the intra-tendinous structures. Tendinosis is an even more advanced stage, marked by degeneration of the intra-tendinous structures, which is caused by atrophy from microtrauma, vascular compromise and/or aging. Tendinitis occurs when there is a tendon strain or tear. You may see an inflammatory repair response with symptomatic overload and vascular disruption. When a patient has chronic tenosynovitis, you may see nodules form in the tendon that place the tendon at greater risk for rupture. Your patient may have inflammation within the tendon sheath and bulbous swelling within the tendon. Causal factors of this response include inflammatory disease, trauma, osseous impingements and abnormal biomechanics. Also consider the possibility of systematic inflammatory disease when multiple tendons are involved. What Is The Best Imaging Modality? While diagnosing chronic tenosynovitis starts with strong clinical suspicion, be aware that clinical and/or imaging findings aren’t enough to confirm a diagnosis of tenosynovitis without tendinosis or interstitial degeneration. Prior to the advent of MRI, doctors used CT scans and ultrasound. However, ultrasound has several limitations. First, it requires a relatively large-sized tendon running in a straight course. The Achilles tendon is the only tendon in the foot and ankle that you can image with ultrasound. This diagnostic modality is also technically difficult to perform. You may consider tenography, but it is an invasive procedure that is difficult to perform. The MRI is the most useful technique in tendon imaging. It allows you to do multi-planar imaging and gives you the ability to evaluate internal tendon tissue as well as peri-tendinous structures. How To Differentiate Between Chronic Achilles Tendinitis And Chronic Achilles Tenosynovitis When it comes to chronic Achilles tenosynovitis, you’ll find that it’s usually caused by overuse injuries. These patients tend to participate in activities which cause stress to the tendon, which goes beyond the tendon’s ability to maintain its normal function. For example, your patient may be a painter or lineman who works on ladders all day or a roofer working on an incline, who subjects the Achilles tendon to tremendous stresses. Achilles tendon injuries are either insertional or non-insertional tendinitis. You’ll often find non-insertional tendinitis of the Achilles among athletes who participate in soccer, tennis, raquetball and basketball. On the other hand, you’ll see insertional Achilles tendinitis among less active, older and often overweight and sedentary patients. Typically, non-insertional chronic Achilles tendinitis occurs at a zone of hypovascularity approximately four cm proximal to its insertion into the posterior calcaneus. This region has been termed the “water shed” area. Chronic tenosynovitis of the Achilles tendon can often be the result of hyperpronation, especially in runners. During the mid-stance phase of gait, the foot remains in a pronated position for a longer period of time. Therefore, pathologic stresses will begin to occur along the Achilles tendon. Then extension of the Achilles tendon occurs later in the gait cycle during the push-off phase, resulting in pathological rotational forces along the Achilles tendon. Overuse is also the most common explanation for chronic Achilles tendinitis. When a patient is running, he or she is exerting forces ranging from nine to 10 times his or her body weight upon the Achilles tendon. However, be aware that changes in training patterns, regardless of the specific athletic activity, can also result in chronic tendinitis. Changes in intensity, frequency and duration of the activity will often exert stresses upon the Achilles, which may eventually turn pathologic. When the patient has acute paratenonitis, you’ll notice crepitus, swelling and tenderness along the tendon length. There also may be pain when you place the tendon through a range of motion exercise. You’ll usually find point tenderness upon palpation with the thumb and forefinger. You may see thickening of the paratenon on an MRI. When patients have paratenonitis with tendinosis, they will often have diffuse thickening that is not easy to localize. You’ll find that their pain is often much worse when you squeeze the tendon. With chronic tendinosis, you’ll notice an area of localized pain and thickening of the tendon along with marked weakness and decreased plantar flexory strength. At this stage, getting an MRI is often not necessary, however, it may be helpful in determining whether you should proceed with non-surgical or surgical treatment. Clinically, you will see a progression of symptoms with chronic tenosynovitis. Initially, these patients will only have pain during the activity. Later, as the tendinitis progresses, the patients will have pain during and after the activity. Eventually, they may have constant pain without activity. Help Facilitate Healing With These Conservative Treatment Tips In your efforts to ensure tendon healing (see “Understanding The Four Phases Of Tendon Healing” on page 36), you can proceed with conservative treatment based solely upon the patient’s clinical presentation. Initially, you should emphasize a modification of activity and perhaps a change in shoe gear. If you’re treating athletes who wish to maintain cardiovascular fitness, have them implement cross training with lower impact workouts. Talk to them about doing gentle stretching exercises of the Achilles, sustaining a gentle stretch for at least 30 seconds. You should also use nonsteroidal antiinflammatories (NSAIDs), ice massage and 1/4-3/8” heel lifts. Since individual response varies, you’ll probably need to try a variety of NSAIDs. It’s also common to use oral steroids, whether you opt for a Medrol Dosepak (4mg) or a tapering dose of Prednisone 10mg or 20mg for a two-week course. In more advanced stages, employing physical therapy and orthoses may be beneficial when treating patients with hyperpronation. The functional orthoses may have a removable heel lift of 1/8” increments with a kick plate. Physical therapy should include a tactful, aggressive treatment plan, including electrical stimulation, ionto/phonophoresis, ultrasound, massage and interferential stimulation. A home interferential unit can be authorized by many insurance companies. As a rule, steroid injections are never recommended for treating Achilles tendinitis, as this may result in further weakening of the collagen cross links, leading to complete rupture. You may employ night splints to maintain a constant passive stretch of the Achilles tendon. Using a MAFO may also prove beneficial for ensuring immobilization and passive rest. Injecting 3 ml of sterile saline into the tendon sheath is a semi-invasive modality for treating chronic para-tenosynovitis. The goal is to separate the paratenon from the underlying tendon in order to reduce adhesions which may have formed through a chronic inflammatory process. Key Surgical Pointers Typically, you should only consider surgical options for chronic Achilles tendinitis cases lasting longer than four to six months. As we noted earlier, getting an MRI can be useful prior to considering surgical intervention as it enables you to determine the extent of the diseased portion of the tendon. Prior to performing surgery, you must address the underlying etiology of the chronic condition. It may be a simple result of improper training, a chronically tight Achilles tendon or, as mentioned previously, overpronation of the subtalar and midtarsal joints. Whatever the case, it is essential to address this underlying etiology prior to, during and after any operative procedure in order to prevent recurrence. There are several surgical options for treating peritendinitis or tendinosis. A simple procedure in both instances consists of making a four cm incision over the area of maximum tenderness. Then you wuld proceed to identify adhesions of the paratenon and excise this portion of the paratenon. In cases of chronic tendinosis, you can make incisions into the area of fusiform swelling, debride and excise the diseased portion of the tendon. Then you can provide suture relief with 4-0 absorbable suture material. If you detect an equinus deformity prior to surgery, you should address this during the same surgical procedure via lengthening of either the gastrocnemius tendon or the gastro-soleal complex. Keep in mind that the level of debridement will help determine the length of time for immobilization. Typically, you can emphasize three to four weeks of non-weightbearing in a below-knee fiberglass cast followed by progression into a weightbearing Cam Walker boot with implementation of physical therapy. Final Notes Getting a good history, doing a thorough clinical exam and using appropriate imaging studies are three keys to diagnosing chronic tendinitis. The duration of the particular pathology will help you determine whether conservative or surgical treatment is necessary. As we discussed, in cases of chronic tenosynovitis about the foot and ankle, you should reserve surgical intervention only for those cases that have not responded to aggressive, non-surgical treatment. Dr. Romansky is a Fellow of the American College of Foot and Ankle Surgeons and a Diplomate of the American Board of Podiatric Surgery. He has a private practice in Media, Pa. Dr. Erfle is a Diplomate of the American College of Foot and Ankle Surgeons.