Most orthopaedic surgeons hate to see a runner coming into the clinic. The injuries are often poorly defined & difficult to diagnose and treat. They rarely require surgery (but may well get an operation if they ask often enough!) and the patient is addicted to the cause of the problem.
By comparison with other sports, the injuries that we commonly see in runners are predominantly to the lower limbs and very largely as a result of micro “over use” rather than macro trauma. They range from the trivial blister to displaced stress fractures which may lead to life long disability. Typically symptoms will develop following a change in stress across musculoskeletal tissues often as a result of changing equipment (particularly footwear) or the type, intensity or duration of training. Most commonly symptoms will respond to a period of relative rest and the difficulty is usually in formulating an acceptable plan for the patient which will keep them out of sport for the minimum amount of time. Carrying the patient with the doctor through the uncertainty of the decision making process is a vital part of this in preventing inadequate rest prolonging the duration of a self-limited condition. The risk of over treatment is also real in unnecessarily prolonging injury either through excessive rest or through the exposure to inappropriate invasive treatments. Running will often form a major part of the patient’s lifestyle an there is often pressure for “something to be done”. This will often lead to patients seeking multiple opinions from a series of practitioners. Patients will often have many modalities of treatment, few of which have any theoretical or empirical evidence of either efficacy or safety.
Runners are usually advised to increase either the training or the intensity of their activity by no more than 10% per week, but even this may be too much and identify a weak point in the musculo skeletal chain. From this point of view it is absolutely vital that patients choose their parents particularly carefully to avoid being “injury prone”. There is surprisingly little convincing evidence for significant correctable structural abnormalities contributing to the vast majority of running injuries. This applies particularly to modification of hind foot biomechanics.
The knee is by far the most popular joint to be injured in most sports, and running is no exception. The “patello-femoral pain” syndrome (previously known as chondromalacia patellae) or simply “anterior knee pain” is commonest of all. In the absence of any major patello-femoral maltracking or instability this is most commonly ascribed to overload of the peri-patellar soft tissues and subchondral bone. The relationship between pathological change in the articular cartilage and symptoms is rather poor. In addition to symptomatic treatment, exercises are suggested which are aimed at decreasing any stiffness or tethering in the peri articular tissues and optimising the balance of the musculature, specifically aiming at strengthening the most distal part of the vastus medialis in an attempt to distribute the forces as evenly as possible across the patella-femoral joint.
Although it is widely held that abnormalities elsewhere in the kinetic chain both proximal and distal contribute to the patello femoral pain - especially foot hyperpronation, the evidence for this is rather limited. Intuitively attractive, the theory is that in patients with flat feet (runners with hyperpronation) there is excessive inversion and eversion movement of the calcaneum. This means that through the gait cycle looking at the patient from behind, the heel moves inwards and outwards excessively. It is normal for this to occur to some extent in that at heel strike, the force is taken on the outside of the heel, and shock is absorbed by the heel turning outwards into eversion and pronation and the arch lowering. During the third part of the stance phase (push-off) the foot stiffens again into supination to give a firm base for pushing off. Because of the oblique axis of the subtalar joint about which this movement occurs, as the heel moves outwards, the axis of the whole limb must rotate inwards about its longitudinal axis (figure 1). It therefore seems entirely plausible that excessive axial rotation of the lower limb caused by excessive pronation will throw more strain more proximally and be implicated in more or less any of the overuse injuries of the lower limb. Anti pronation insoles are therefore very commonly prescribed either off the shelf or custom made, typically in association with a running shoe that provides a little more longitudinal stiffness to rotation, a bit more arch support and a little more support of the medial side of the heel either with increased density or increased medial flare of the outsole. The evidence for these biomechanical corrections is rather limited for knee problems or even tibial stress injuries, with some authors suggesting that a high arched “stiff” foot may predispose, whereas others that a “soft” pronating foot may either tire more quickly or lead to increased torsional stress.
Other more specific diagnoses around the knee are of the plica syndrome, patellar tendonopathy and ilio tibial band syndrome.
In the plica syndrome, patients are predisposed to discomfort medial to the patella caused by an impingement of a congenital synovial fold which abrades the medial border of the medial femoral condyle. Symptoms will usually settle spontaneously, but with chronic scarring, the plica may need arthroscopic removal.
The second commonest diagnosis of pain in the runner’s knee, behind patello femoral pain is the ilio tibial band (ITB) syndrome. The ilio tibial band runs from the iliac crest to the antero lateral tibia, distal to the knee joint, and runs over the prominent convexity of both greater trochanter and lateral femoral condyle. At either point, over use may lead to inflammation & pain which will usually settle with a period of rest, often with physiotherapy modalities. It may be helpful to stretch the structure to relieve the pressure underneath it. There is evidence for the role of locally-injected corticosteroids in the ITB syndrome and they may also be used for inflammation proximally at the greater trochanter where there is trochanteric bursitis.
Atraumatic, degenerate meniscal tears are surprisingly common especially in the older age group & are very rewardingly treated surgically.
Perhaps the most controversial pathology in the runner’s lower limb is that of tendonopathy. Achilles, patella, adductor and various other tendonopathies are particularly common and often difficult to treat. Whilst occasionally there is inflammation and it is certainly possible to have a tenosynovitis where a tendon has a synovial sheath, tendonopathy is a non-inflammatory condition for which there is no logic for the use of anti inflammatory agents either injected corticosteroids or non steroidals. The pathophysiology appears to be an overload injury to some of the collagen fibres within the tendon leading to a very low grade healing response in the presence of rather poor vascularity. Overloaded adjacent fibres may then fail leading to either focal or more commonly widespread low grade injury and low grade healing response throughout the tendon with thickening, chronic scarring & loss of elasticity with neovascularisation. Typically patients with tendonopathy will be uncomfortable first thing in the morning, be able to loosen off the tendon, but get exertional and particularly post-exertional discomfort with stiffening. A very wide variety of treatments are offered for these conditions with varying degrees of theoretical or pragmatic support. Relative rest is probably a good plan but without allowing any contracture. Particularly in the Achilles tendon, but also elsewhere, there is good evidence to support what appears to be exactly the opposite, through following a programme of eccentric strengthening. This is recommended for Achilles tendonopathy typically standing on tip toes on the bottom step before progressively lowering the weight down, putting the foot into full dorsi flexion using only one leg. The patient therefore goes up onto tip toes using both calf muscles and descends eccentrically loading just the affected side. It is usually recommended that this should be uncomfortable to the patient and when he or she is able to complete this 10 or 15 times, weight should be added through a rucksack. To be effective this needs to be continued daily for several months. It is known that musculo tendinous units can be selectively strengthened for eccentric as well as concentric work and that many of the commonly injured musculotendinous units do work primarily eccentrically. Both hamstrings and the gastrocnemius part of the triceps surae span multiple joins in the kinetic chain, and function rather less as prime movers than as transmitters of force down the chain. In the case of the gastrocnemius, which runs from the posterior distal femur to the heel, quadriceps contraction leads to knee extension and this will automatically lead to plantar flexion at the ankle and enhanced push off during the gait cycle if the gastrocnemius does not change length.
Similarly recurrent hamstring tears can be to a very large extent prevented by prophylactic eccentric strengthening exercises.
A wide variety of substances are injected in and around tendons in an attempt to accelerate recovery. Broadly, corticosteroids are probably not a good idea. There has been a recent vogue for alternative and homeopathic preparations such as Actovegin and Traumeel and more recently autologous whole blood or a platelet-rich concentrate thereof have become popular. Dry needling, prolotherapy and other sclerosant injections often specifically aimed under ultrasound control to reduce the neovascularisation may all work through the same final pathway either of denervation or a mechanical stimulus to the healing process.
Other modalities used for tendonopathy are extra corporeal shock wave therapy for which there is now good evidence in plantar fasciitis and calcific tendonitis elsewhere. It may well be an effective modality for other tendonopathies. Surgery is always very much a last resort.
The term shin splints should probably now be abandoned as it is used by different people to mean different things. There is a long list of causes of exertional shin pain including stress fracture, exertional compartment syndrome and neurovascular compression. Again biomechanical compromise, particularly hyperpronation has been associated with exertional shin pain and is theoretically attractive.
Pragmatically, the pathology may be if not neurovascular, then either in the soft tissues or the bones. Stress fracture will be visible after a couple of weeks on a plain x-ray, but is picked up very sensitively with an isotope bone scan. This will also show the more diffuse “stress reaction” of the medial tibial stress syndrome which contrasts with the focal area of dramatically increased uptake seen in stress fracture. Stress fractures are most commonly seen in the posterior cortex and settle very reliably with a period of relative rest (usually fully weight bearing without splintage for activities of normal daily living, avoiding impact loading for 4-6 weeks). A very gradual return to sport after the patient is asymptomatic for 10-14 days, often requiring several months to return to full activities. The dreaded black line of a transverse stress fracture in the mid-anterior tibial cortex is a very different matter. This lies in the convex (so called “tension”) side of the bone and is very slow to heal, commonly requiring surgery either to stabilise with an intra medullary nail or to stimulate locally with either cytokines or bone graft. As with tendonopathy, there are a variety of poorly tested & alternative accelerators of bone healing, some of which are probably harmful. There is some evidence for a small effect of commercially available bone-growth stimulators either ultrasound or electromagnetic.
Exertional compartment syndrome may involve any of the four fibro osseous compartments seen in a cross section of the shin. The typical history here is of a progressive tightening and aching in the shin which it is impossible to run through. It is sometimes associated with tingling in the distribution of a nerve passing through the compartment involved. The diagnosis here is primarily a clinical one which may be supplemented either with direct exertional compartment pressure testing, transcutaneous near infra red spectroscopy or post exertional magnetic resonance imaging. The treatment is surgical release.
Stress fractures may occur elsewhere in the lower limbs especially the foot. Metatarsal acute on chronic stress fractures have been popular recently in high profile footballers. They have been associated with stiffer feet, stiffer footwear and an abnormal flexed pattern within the shoe. The commonest proximal fifth metatarsal metaphyseal stress fracture (“Jones fracture”) will usually heal if treated conservatively, but heals more rapidly, more reliably and with a lower risk of recurrence in athletes following surgical fixation. Stress fractures in the foot and ankle may also occur in the second metatarsal neck (March fracture) and malleoli with a benign prognosis, but there has been an increased incidence of navicular stress fractures in recent years. This is not a benign injury and requires prolonged immobilisation with some evidence to support prolonged non weight bearing and possibly early surgical fixation.
Stress fractures of the hip and pelvis are also seen and have been most widely studied in army recruits. Fractures of the femoral neck will often require early internal fixation to avoid the risk of the disastrous consequences of displacement.
Any fracture may occur due to an abnormal force or an abnormal bone & the “female athletic triad” of disordered eating, menses and low bone density is the commonest cause of pathological fracture in athletes.
Most running injuries will settle with relative rest and the passage of time. There are a very wide variety of treatments on offer many of which do little harm while this happens, but some do require early intervention & very occasionally, surgery.