The performance demands of ballet are comparable to many highly competitive athletic pursuits. Although dancers are artists and not athletes, the athletic demands of dance choreography place the dancer at risk for injuries. Fifteen to 20 percent of dance injuries involve the foot. Chronic injuries tend to predominate as they are related primarily to the repetitive impact loading of the dancer’s foot on a relatively hard, unyielding surface: the dance floor. Unlike the athlete, who often wears a shoe specially designed to stabilize the foot and absorb shock, the ballet dancer wears only a thin slipper or toe shoe. Therefore, the majority of the forces of impact in this setting must be absorbed by the lower extremities. It is the failure to effectively and efficiently absorb these forces that can lead to injury to structures about the foot. Factors that can contribute to this ineffective absorption of energy include anatomic variation, improper technique and, in some cases, fatigue. Exploring Anatomical And Technique-Related Causal Factors The single most important anatomic factor in classical ballet is proper turnout of the hip. Each of the five basic positions has a single common denominator: maximum external rotation of the hip. All ballet movements begin or end with one of these positions. The aspiring dancer who has the good fortune of ligamentous laxity may have greater potential for superior turnout than “tighter” dancers. Dance students with poor “natural” turnout at the hip may compensate by forcing external rotation at the knee or the foot and ankle joints. Rolling in, the equivalent of excessive pronation, is a technique employed by some dancers to compensate for inadequate external rotation at the hip. Rolling in involves eversion of the hindfoot with forced pronation of the midfoot and forefoot. The consequence of such a maneuver is excessive strain on the medial structures of the foot and ankle, and can lead to chronic injuries. A cavus foot, with its inherent rigid midtarsal joints, can also present problems to the aspiring ballet dancer. The cavus foot absorbs energy poorly and often diverts forces to structures unaccustomed or poorly suited to absorb stress. Cavus feet are especially vulnerable to ligamentous strain, fasciitis and stress fracture. A dancer is best off with a broad, square foot so the forces are shared equally by all the metatarsals running down to the ball of the foot. The Morton’s foot, with its shortened first and fifth rays, is prone to soft corns and fractures at the base of the second metatarsal. The splayfoot has metatarsus primus varus, which is usually accompanied by a hypermobile first ray. This foot has a tendency to pronate or roll in, and is often a precursor to hallux valgus and bunionettes. While the normal range of motion in the first metatarsalphalangeal joint is 63 degrees of dorsiflexion and 37 degrees of plantarflexion, dancers must routinely have 90 to 100 degrees of dorsiflexion to allow a full relevé onto demi-pointe. This motion is usually obtained by dancing while the musculoskeletal system is forming so the joints can be molded. Unfortunately, there are some young dancers who never develop adequate motion in this important joint. These individuals will have a very difficult time dancing ballet or modern dance, and are better off studying jazz or tap. How Shoes And Surfaces Contribute To Injuries Traditional ballet shoes cost between $40 and $75 a pair. However, they can break down and wear out after only one demanding performance. Each shoe is handmade of satin and ribbon. The shoe allows for shock absorption by having a stiff cardboard midsole, cotton insole and a stiff cardboard outsole. Forming the tip of the shoe is glued canvas that allows dancing on full pointe. Be aware that because these shoes are handmade, there are often irregularities in the construction and fit of each shoe. This in itself can contribute to injury. Injuries may also occur when the ballet shoes have worn out. Dancers know the shoe is worn out when it becomes too soft and no longer supports them en pointe. Many times, the shoe will collapse, causing the dancer’s foot to roll over when en pointe. The dance surface is another variable that has great bearing on the dancer’s ability to perform adequately. Dance surfaces must provide adequate shock absorption yet be firm enough to provide sufficient energy return to the dancer to enhance performance and reduce fatigue. Surfaces that are too firm with little or no give (such as concrete and asphalt) may lead to early muscular fatigue because the musculoskeletal system of the lower extremities must act to absorb most of the shock. Once this system fails to absorb shock adequately, afflictions of the feet (e.g., stress fractures) may follow. On the other hand, if a dance surface is too soft, this too can lead to early fatigue. In this situation, there is adequate absorption but inadequate energy return to the dancer, thus requiring considerably more effort to perform the desired movements. Early fatigue often leads to injury. Inside Tips On Evaluating Common Foot Injuries One should evaluate the ballet dancer’s foot problem in a sport-specific fashion. Instruct dancers to bring their slippers and pointe shoes to the evaluation so you can examine them for signs of abnormal stress or use and worn when appropriate. A general foot assessment is best supplemented by asking the dancer to perform the maneuvers or assume the positions that aggravate or induce the symptoms. If the movement permits, you can carefully palpate the affected region during that athletic stress. You should keep an eye out for some of the following conditions: Epiphysitis. The necessity for 90 to 100 degrees of dorsiflexion in the first metatarsalphalangeal joint has been noted. People are rarely born with this much motion in this joint, so it must be obtained by some molding of the growing epiphysis. This motion can result in an epiphysitis of the proximal phalangeal epiphysis during adolescence, which presents with tenderness, inflammation and pain with activity that is relieved by rest. The condition tends to recur, but disappears when the epiphysis fuses at maturity. This condition, in many ways, resembles Osgood-Schlatter disease that is commonly seen in the adolescent’s knee and is known as Osgood-Schlatter disease of the foot. As far as treatment goes, you should emphasize modified activities for four to five weeks until the symptoms subside and then allow gradual resumption of normal routines as tolerated by the patient. Treatment Advice For Bunions Bunions. Bunions are common in dancers. They begin to develop at the end of the teens and occur in both male and female dancers. They are often symptomatic at the end of class, since the foot is forced into a tight shoe. Padding with lamb’s wool around the tender area is a simple and effective means of relieving pain. Placing spacers between the first and second toes will usually make the foot more functional, as this alignment maintains maximum motion in the MPJ. The young female dancers with this problem should be encouraged to wear wide shoes (e.g., boy’s sneakers) and to resize their toe shoes often. It should be done at least yearly and every six to eight months if they are in a growth spurt. If you’re treating a serious dancer, you should never operate on bunions because the operation, no matter how carefully it is performed, will usually limit the motion in the first MPJ. Addressing Sesamoid Pain In Dancers Sesamoiditis and sesamoid fractures. Sesamoiditis and sesamoid fractures can be annoying problems because they heal so slowly. Sesamoiditis has many causes. Here are some causes to keep in mind. • Contusion. Contusions will respond to conservative therapy but often heal slowly. • Sprain of a bipartite sesamoid. The injury X-ray film compared to an old film will sometimes show widening of the distance between the two fragments. • Stress fracture. The bone scan will be positive. • Fracture. A fracture will usually heal either by bone or fibrous union. • Avulsion fracture of the proximal pole. • Osteonecrosis. This condition occurs often in the lateral sesamoid, occasionally in the medial and in both on rare occasions. The cause is unknown and the prognosis is often poor because the bone may fragment as it heals and pain may persist. In some patients, healing will occur but the process is slow and uncertain. • Osteoarthritis with loss of the cartilage space and spur formation. You’ll usually see this on the X-ray sesamoid view and it usually affects adults. • Entrapment neuropathies, especially adjacent to the medial sesamoid, can mimic sesamoiditis or be part of the problem. In this condition, a Tinel’s sign will usually be present. Performing a sesamoidectomy is usually not necessary for dancers because the pain will almost always subside eventually with conservative therapy alone. It is often difficult to get the dancer to be patient but the pain will usually go away if one can just wait long enough. (The exception to this rule is osteonecrosis.) Conservative therapy of sesamoid problems may take six to 12 months. During this period, you may use pads to offload the sesamoids and dancers should minimize demi-pointe work. If the dancers still have disabling symptoms after one year of conservative treatment, you may consider a sesamoidectomy. When you’re treating osteonecrosis, you may shorten the period of conservative treatment to six months, given the poorer prognosis associated with this condition. However, keep in mind that you should never remove both sesamoids. Dr. Caselli (pictured) is an Adjunct Professor in the Department of Orthopedic Sciences at the New York College of Podiatric Medicine. He is a staff podiatrist within the VA Hudson Valley Health Care System in Montrose, N.Y.
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