The following essays are extracts of monthly articles written for the Syracuse Track Club newsletter by Dr. Dan Wnorowski.
Click on a topic below.
Five Problems You Should Not Run Through
Shin Splints and Stress Fractures
Running and Arthritis
Here’s a topic I am continually asked to comment about: does running cause osteoarthritis (OA)? The answer is that no one knows for sure. However, I will first review some interesting studies that shed some light on the answer to this question. Then I will describe my own personal opinion, from the perspective of a runner and an orthopedic surgeon.
There is absolutely no doubt that running causes injury. Two studies published in 1989 from Canada and California surveying large numbers of competitive runners found that they reported injury rates of 48 and 50% within the prior year.1,2 Also in 1989, a survey of participants of the Hawaii Ironman event revealed an astounding 91% rate of injury during the prior training year!3 Therefore, it seems intuitive that with rates of running injuries being so high, and with so many injuries involving the weight-bearing joints of the lower extremities, repeated injury must predispose to arthritis over a lifetime of running!
However, I am happy to report that the majority of the relevant literature during the past decade finds little or no basis for such a conclusion. Here are some highlights. 1995: Panush, et al, in “Is Running Associated With Osteoarthritis? An Eight Year Follow-up Study”, conclude that runners with “reasonable” exercise levels had no increase in risk of arthritis, after reviewing detailed histories, exams, and X-rays in an update of a 1984 study of the same cohort.4 1993: Lane, et al, in “Risk of Osteoarthritis With Running and Aging: Five Year Longitudinal Study”, looked at older runners (age 50-72), and noted no acceleration of degenerative joint disease in runners versus controls, similar to their previous study in 1989.5,6 1990: Konradsen, et al, also evaluated a possible association between long-distance running and OA, via retrospective evaluation of former competitive runners who ran 20-40 kilometers per week for 40 years average, versus sedentary controls. They found little to no risk of OA with lifelong long distance running.7 Interestingly, a recent MRI study indicates that the prevalence of knee meniscus abnormalities in asymptomatic marathon runners is no different than sedentary controls.8
To be fair however, there are some reports of association of OA of the hip and an athletic lifestyle. Vingard, et al, in 1993 and 1998, found that both men and women with “high exposure” (>800 hours/year) to athletic activities in early life demonstrated 4.5 and 2.3 times the risk, respectively, of development of OA of the hips versus controls. The risk was even higher if they also endured high occupational workloads, 4.3 and 8.5, respectively!9 ,10 In 1989 and 1993, studies from Switzerland and Sweden found correlations between prior elite track and field competition and OA of the hip.11,12 There is virtually no mention of a positive correlation of knee OA and running, though a 1990 MRI study found that of 10 asymptomatic runners volunteering for MRI knee exams, 5 demonstrated transient changes in meniscal signals, usually interpreted as degeneration, after 30 minutes of running, versus resting baseline images.13
So what does it all mean? Until we know more, common sense must prevail!
At local races, I look around and recognize faces of many runners from whose knees I have removed torn cartilage. I have told these competitive distance runners that there is increased risk of arthritis after loss of meniscus cartilage from the knee. My feeling is that if there is a strong family history of OA, and/or if there is persistent and consistent pain and swelling in the knee in response to running, they are probably better off switching to low impact activities. These include swimming, cycling, cross-country skiing, or at the very most, treadmill running. The same would apply to the patient with an arthritic hip or knee. Pain in the area of the joint line or back of the knee, or in the groin, or front of the hip, means an angry and irritable joint! Swelling is always a bad sign, but it is nearly impossible to appreciate hip joint swelling. Hip stiffness is a better indicator. However, we are ultimately the masters of our own bodies. As a physician and surgeon, I treat people, and not just knees. Therefore, an educated patient may decide to pursue running despite loss of the cartilage, and the potential for arthritis.
Next time, for those with cartilage damage or early arthritis, what’s the scoop on cartilage supplements? Is this a panacea?
References abbreviated to save space: 1- Walter, et al. Arch. Int. Med. 1989. 2- Macera, et al. Arch. Int. Med. 1989. 3- O’Toole, et al. AJSM. 1989. 4- Panush, et al. J. Clin. Rheum. 1995. 5- Lane, et al. J. Rheum. 1993. 6- Lane, et al. JAMA. 1989. 7- Konradsen, et al. AJSM. 1990. 8- Shelloch, et al. AJR. 1991. 9- Vingard, et al. AJSM. 1993. 10- Vingard, et al. AJSM. 1998. 11- Marti, et al. BMJ. 1989. 12- Vingard, et al. AOS. 1993. 13- Kargunoglu-Brahme, et al. AJR. 1990.
Dan Wnorowski, M.D.
Five Problems You Should Not Run Through
Every single day, runners make judgements about the aches and pains they gather along their routes. The majority are blocked-out, and the running continues, perhaps with the aid of ice, anti-inflammatory medication, adjusted mileage or intensity, or, in many cases blind hope that the pain will “just go away”. While most running related problems are not serious, rarely symptoms may indicate a problem that cannot be ignored without risk of serious consequences. While running up Pompey Center Road recently, in the midst of an unseasonably beautiful and warm sunny afternoon, I found myself negotiating with knee pain. ,To distract myself I thought of five situations that runners should not ignore, not try to run through, without seriously pressing their luck. One must keep one’s allotment of good fortune for the times one really need it, and not waste it on training in pain in such cases.
The number one most important problem is chest pain. There is no excuse for running through chest pain, especially if left sided, plus or minus radiation of the pain down the arm or into the neck. Sure, the pain could just be indigestion, or a rib muscle cramp, but chest pain should be acknowledged. Seek professional help, especially if there is dizziness, shortness of breath, a history of sudden death in the family, or prior smoking, high cholesterol, or high blood pressure. Such pain may indicate an impending heart “event”, like death for instance.
Another serious problem, though not likely to kill a runner, is hip or groin pain (pain in the front of the hip, in the region of the skin crease, or radiating into the thigh). This pain should not be neglected, especially if there has been an associated increase in training intensity or mileage. Perhaps the worst stress fracture I can think of is that of the femoral neck, the junction of the sjaft and ball of the thigh bone. Such a fracture can be a career ending injury.
Next is back pain accompanied by leg pain, particularly pain that “shoots” down the thigh, particularly the back of the thigh, occasionally below the knee to the foot. The leg pain typically is “electrical” in nature, and may present without back pain, or with numbness, weakness or rarely, bladder or bowel troubles (loss of control). Unless running from a pit-bull, I cannot understand while anyone would try to “run through” , this problem, but I have heard this story countless times.
Shin pain, if progressive, persistent, and localized may indicate a tibial stress fracture. Nearly all runners will attribute shin pain to shin splints, and will run through this injury, at least at first. Once again training intensity and mileage are culprits, as is excessive pronation (flat foot), new shoes, running on the same side of the road, etc. A good clue is the distribution of pain and tenderness. Shin splints are usually tender longitudinally up and down the leg, typically medially (on the inside), whereas stress fractures are more localized, like the shape of a coin.
Finally, not all knee pain is “runner’s knee”. Knee pain, especially after a run and accompanied by swelling, should not be ignored. Swelling is the best indicator of a potentially serious problem. Small amounts of fluid within the knee joint more often than not go unnoticed by runners. A good test to increase your recognition of fluid is to place the palm side of the hand immediately above the kneecap and push downward. If the normally concave areas on the sides of the kneecap bulge, fluid is likely to be present, which may indicate torn cartilage, or damaged joint surfaces (arthritis). Running under these conditions may make the knee seriously worse.
Everyday in my office I see runners with overuse injuries. All try to manage their problems, and most are successful with minor injuries. However, these five situation are in a category by themselves, and merit prompt recognition for the special dangers they present to the runner’s well-being and future success. If in doubt, get it checked out!
Dan Wnorowski, M.D.
Shin Splints and Stress Fractures
This is the time of year that I see several patients with complaints of leg pain aggravated by their running endeavors. Most often, the runner has begun the fall cross-country season and has ratcheted up the mileage substantially over a very brief period (several weeks). Usually the typical story goes like this: “I have pain in my shins during running, on the inside part, that gets worse with running, but sometimes I can run through it. I ice every time after my runs, but it seems to be getting worse. There is no pain with walking…my coach and trainer say it’s probably just shin splints, but my mom (a runner) is worried about a stress fracture.”
Every year, three to six runners come in with this story. First, I clarify the story. Where is the pain: medial (inside, toward the other leg), usually around the junction of the middle and distal thirds of the bone. Whendid it begin: came on gradually during the second week, “we were increasing mileage…worse third and forth weeks…more consistent during runs, lasting longer, even after”. Training history: didn’t do much running during the summer, doing other activities (camping, lacrosse camp, etc.)…”maybe running ten-fifteen miles per week…sudden increase with my fall training runs”. Shoes: new shoes (“they discontinued my old line, but these felt comfortable”). Treatment: still running (with pain), but stretching, and taking ibuprofen, with icing after runs- “no relief”.
The problem here is that although stress fractures of the tibia are far less common than shin splints, stress fractures mandate complete cessation of running. Sometimes shin splints do too, but the runner can often diminish mileage, modify footware, take anti-inflammatory medication, ice and stretch, and get through a bad case of shin splints. Stress fractures are a different story. It is virtually impossible to heal an established stress fracture without avoiding high impact activity.
So, the difference makes a difference. How can one distinguish the two? As we have seen, the history is not much help, although establishing the precise location of pain and tenderness may provide clues. Stress fractures usually cause more localized pain and tenderness, often transverse (a line parallel to the ground when standing), whereas shin splints often produce more longitudinal pain and tenderness, i.e.- up and down the leg, perpendicular to the ground when standing. Shin splints are more often bilateral, while bilateral stress fractures are rare. But (there is always a “but” in medicine) there are always exceptions to these generalizations.
Therefore, for persistent leg pain with the above story, get it checked out. X-rays are unreliable for early detection of stress fractures, as they are often normal, even when a fracture is truly present (“false negative study”). This is because the “crack” may be so small (even microscopic) that it cannot be seen on the x-ray picture. Most often, the first x-ray sign of a stress fracture seen on x-ray is the new bone of healing, “callus”, a late finding. Therefore, more sensitive (but more expensive) tests may be necessary to distinguish the two, such as a bone scan or MRI.
The best “treatment” for these two problems is to avoid them in the first place: ramp up mileage slowly, stretch before and after running, wear appropriate shoes, avoid same side of road running, and cross train. For those student athletes that anticipate fall cross-country, or spring track, maintaining a good pre-season mileage base is wise, increasing gradually prior to the season. Alternate between two pairs of training shoes to allow time for the cushioning to recover. In my experience, shin splints seem to be more common in flat-footed runners (pronators), and supportive shoes with a good arch may prevent trouble.
Dan Wnorowski, M.D.
Shin Splints, Shoes & Tendons
One of the most common troublesome conditions that can plague the runner is “shin splints”. This entity classically presents as pain on the inside of the shin bone (tibia), usually in a longitudinal distribution (up and down the leg), typically in the lower third. It is often bilateral. I most commonly see this problem in runners with a history of sudden increases in training mileage or intensity, those that run on the same side of the slanted shoulder of the road, or those with a change in footware.
Every runner has a unique foot, and the arch of the foot is especially variable. The arch of the foot can be high and rigid (the “cavus” foot), or low and flexible (the “flat foot”). Furthermore, the flat foot, though most often flexible, can be fixed, or rigid. It is the flexible flat foot (“pes planus”, or “pronation”), that contributes to the shin splint problem.
The arch of the foot is made up of a column of bones much like the architectural “Roman arch”. These bones are arranged apex upward, and tethered together by a series of ligaments that bind and support the bones. But like any structure, the arch may be prone to fatigue and collapse. Therefore, the muscles and tendons that help support the arch are extremely important. The main muscle-tendon unit that supports the arch is the posterior tibial tendon. As it’s name implies, it originates from the back (posterior) of the tibia, traverses behind the medial malleolus (bump on the inside of the ankle), and attaches near the apex of the arch to help support it.
Shoes are also very important and will be the focus of this discussion, as they relate to the shin splint problem. We all have heard the importance of “supportive shoes”, but what does this really mean? For the runner with flatfoot tendency, or with a “tired arch”, support means a cushion in the shoe, or some sort of “motion control” component engineered into the shoe design which serves to prop up the arch. The motion the shoe is supposed to control is pronation, or simply, collapse of the arch during stance phase (with weight-bearing). This usually means stiffening the area directly adjacent to ad beneath the arch (tough plastic buttresses are common, or a different material in the outer sole beneath the arch). Sometimes special insoles will do. This can make a big difference in avoiding arch overuse, strain, and collapse.
So what does this have to do with shin splints? A supportive shoe is very important in the feet of those with flexible flatfoot, i.e.- pronators, to prevent fatigue of the arch, and hence, stretching and fatigue of the posterior tibial tendon. Overuse of the posterior tendon can present as either a tendinitis, or shin splints. The symptoms vary from pain in the arch, pain behind or below the medial malleolus, or along the inner shin. Swelling may sometimes be present. Treatment is aimed at reducing inflammation (ice, medication, etc.), resting the inflamed tissue (decreased mileage, avoiding the cambered side of the roads, etc.), and supporting the arch, and secondarily, the posterior tibial tendon (shoe modifications).
A word of warning. If pain persists despite these conservative modifications, one must consider the possibility of more serious injury, such as tibial stress fracture, or posterior tibial tendon tear. Also, numbness in the foot is not typical, and suggests other problems, as well. If in doubt, get it checked out!
Dan Wnorowski, M.D.
Foot Alignment
Running Injuries and the Shape of the Foot- Pronation:
A very interesting aspect of orthopedics is the predictability of injury. Patterns exist in nature, and a correlation is often seen between the shape of one’s foot and the injuries one may encounter. “Experience” then becomes nothing more than pattern recognition: the realization that certain types of foot alignment predispose to specific types of problems. Of course there are exceptions, and the following examples represent generalizations only.
Most runners are familiar with the term “pronation”. This describes a foot that is flat. In other words, the arch is minimal, or even absent. A pronated, or flat, foot, can be rigid or flexible. Rigid means that the deformity is fixed or constant, and independent of weight-bearing. A flexible flat foot presents only with weight bearing, and the arch is restored when weight is off the limb. The function of the arch is two fold: shock-absorption and energy-storage, and it acts similarly to the leaf spring of a car. The arch is supported by many small ligaments and by the posterior tibial tendon, which serve to maintain and control the arch.
The only other fact that is essential to understand is that a relationship exists between the normal “controlled collapse” of the arch with weight-bearing and rotation of the lower leg. This occurs through the complex series of joints between the leg and foot. In short, the greater the tendency toward pronation (the greater the flexibility and flattening of the arch), the greater the rotation of the lower leg. This is the basis for many of the overuse injuries that correlate with the pronated foot.
Thus, rotation of the leg that occurs with each and every step, can produce torsional, or twisting, forces on the soft tissues that attach to various parts of the leg. If excessive, one may develop patellar tendinitis, or shin splints, for example. Furthermore, rotation of the lower leg also affects the alignment and motion of the patella, which can produce pain in and around the patella, called “patellofemoral syndrome”. The focus therefore, is controlling pronation by supporting the arch of the foot, in addition to treating the symptoms and problems above the foot. Often, simply using a more supportive shoe, one which incorporates some type of “motion control”, or arch buttress, will do the trick. Another option is a supportive insert (“arch support”), i.e.- an orthotic. It is useful to check the shoe first, as it is easy to buy the wrong type. Custom orthotics can be expensive. Over-the-counter varieties are much cheaper, and can be useful as a short-term trial.
Running Injuries and the Shape of the Foot- Supination:
Several issues ago, the concept of foot shape and injury correlation was introduced. The pronated foot is a “flat foot”, one with a diminished, arch. Recall that the function of the arch is two fold: shock-absorption and energy-storage. The arch is supported by many small ligaments and by the posterior tibial tendon, which serve to maintain and control the arch. Furthermore, the greater the tendency toward pronation (the greater the flexibility and flattening of the arch), the greater the rotation of the lower leg. This is the basis for many of the leg overuse injuries that correlate with the pronated foot.
The opposite of the pronated or flat foot is the supinated, or high-arched foot. The chief characteristic of the high arch is its rigidity. It lacks the controlled collapse characteristics of the normal arch. Without this flexibility and collapse, there is reduced capacity for shock-absorption and cushioning. In addition, there is decreased energy-storage without the controlled arch collapse of the supinated foot. It has been shown that more than 50% of the energy absorbed with arch collapse is retransmitted to the limb with toe-off. Hence, the supinated foot is a less-efficient, stiffer, less cushioned foot, relative to its opposite.
Remember that the pronated foot transmits torsional (twisting) forces upwards within the limb secondary to the complex biomechanics of the ankle and other joints of the hindfoot. The supinated foot then, by virtue of its stiffness, confers little rotation, as there is minimal arch collapse, but rather transmits direct impact forces up the leg. Unfortunately, just as the twisting forces of the pronated foot can contribute to injury, so too can the direct waves of concussion transmitted by the supinated, high-arched foot. However, these forces are more likely to produce high impact type injuries.
Injuries most likely to occur because of impact transmission most commonly include stress fractures. These may include sites such as the tibia (lower leg), and neck of the femur (hip). These pounding forces may even effect more distant locations such as the sacroiliac joints of the lowest portion of the back and pelvis, and the lumbar spine (low back). Symptoms may include running related leg, knee, groin, and low back pain. Whether these forces can actually contribute to arthritis of the knee, hip and spine is debatable. Evidence is controversial (see below web site for archived discussion of running and arthritis).
Just as orthotics may be helpful to the injured pronator, they may also benefit the supinator. Extra cushioning is essential in this type of foot. Usually, this involves the use of shock-absorbing inserts, for example, viscoelastic substances, commercially available at most running stores. Certain shoes are designed with extra padded soles for the same function. These shoes utilize a variety of substances including closed-cell midsoles, air chambers, and gel pads within the heel. The effectiveness of these substances is variable.
In summary, it is useful to know the type of foot architecture one must live and run with, in order to select the correct shoe type, and to avoid and recover from injuries. The pronated foot needs arch support to control excessive arch collapse and limit the rotational forces transmitted upwards within the leg. The supinated foot needs cushioning to compensate for the lack of arch collapse and shock-absorption, with excessive axial forces passed upstream.
Finally, excessive pronation and supination represent the extreme ends of the spectrum, the “toe regions”, or small ends of the population curve. Most feet are in between, with average, or relatively “normal” arches.
Dan Wnorowski, M.D.
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