The most easily found sesamoid bone is the patella, or the kneecap. It is embedded within the patellar tendon that attaches the quadriceps to the tibia. The patella provides an extra mechanical advantage to the thigh, helping extend the knee the last 30 degrees. It guides the knee properly into a flexed position 2. Knee pain is one of the most common complaints of the lower extremities. People of all ages may experience discomfort and injury in the knee. In many cases, the movement of the patella is a primary cause of this discomfort.
Treating an inflamed patella patellar tendonitis can be complex. Any one of countless biomechanical factors could cause discomfort. These factors vary from person to person, making each case different from the next. Generally, a practitioner will start by addressing the most common factors that lead to patellar tendonitis. These include foot mechanics when walking: posture, hip position, knee angle, and other factors that could lead to stress.
Once you find the primary biomechanical weakness, you can continue with the appropriate therapeutic intervention. Many therapists recommend closed-chain eccentric exercise for patellofemoral pain. The eccentric phase of muscle contractions loads the muscle and tendon without placing excessive force on the knee joint or patella.
For example, the Eccentron is a closed-chain, eccentric-only system that gradually loads the entire lower kinetic chain.
Clinicians have long valued the benefit of eccentric exercise and recently, it has gained even more attention for treating weakened or injured tendons. Watch this video to see how the Eccentron can restore strength to deconditioned lower extremities.
After repetitive training, the tendon becomes stiffer, and can provide better force control of the patella during walking and running. Exercise with the correct biomechanics is key to long-term success for patellar tendonitis patients. In addition to the knee, you can also find sesamoid bones in the hand. Most people have five hand sesamoids. The most common hand sesamoids are two small bones that start at the base of the thumb distal aspect of the first metacarpal. Injury to these bones can be difficult to diagnose.
Therefore, research articles and case studies rarely feature sesamoids of the hand 3. Patients with upper extremity injuries or surgery often need multiple therapy sessions to make a full return to function without pain. Start by addressing the isolated movement of the hand and wrist. The cause is often variations in position of the 1st metatarsal bone or great toe, such as lateral angulation The pain of sesamoiditis is beneath the head of the 1st metatarsal; the pain is usually made worse by ambulation and may be worse when wearing flexible thin-soled or high-heeled shoes.
Occasionally, inflammation occurs, causing mild warmth and swelling or occasionally redness that may extend medially and appear to involve the 1st metatarsophalangeal joint. Sesamoid fracture can also cause pain, moderate swelling, and possibly inflammation. With the foot and 1st big toe dorsiflexed, the examiner inspects the metatarsal head and palpates each sesamoid. Tenderness is localized to a sesamoid, usually the tibial sesamoid.
Hyperkeratotic tissue may indicate that a wart or discrete callus is causing pain. If inflammation causes circumferential swelling around the 1st metatarsophalangeal joint, arthrocentesis is usually indicated to exclude gout and infectious arthritis.
If fracture, osteoarthritis, or displacement is suspected, x-rays are taken. Sesamoids separated by cartilage or fibrous tissue bipartite sesamoids may appear fractured on x-rays. If plain x-rays are equivocal, MRI may be done. Simply not wearing the shoes that cause pain may be sufficient. If symptoms of sesamoiditis persist, shoes with a thick sole and orthotics are prescribed and help by reducing sesamoid pressure.
If fracture without displacement is present, conservative therapy may be sufficient and may also involve immobilization of the joint with the use of a flat, rigid, surgical shoe. Although surgical removal of the sesamoid may help in recalcitrant cases, it is controversial because of the potential for disturbing biomechanics and mobility of the foot.
Dancers, joggers, and people who have high-arched feet, wear high heels, or have bunions can develop pain at the sesamoids beneath the head of the 1st metatarsal.
Diagnose based on clinical findings; exclude infection with synovial fluid analysis when swelling is present and exclude suspected fracture with x-rays. These stress fractures occur in running, court sports and dancing due to high impact and compression. These fractures are characterized by pain, which may limit play or performance. A standard radiograph two to three weeks after the initial injury will reveal a stress fracture to the sesamoid bone.
When there is suspicion of a stress fracture, it may not be readily apparent on plain film radiographs. A clear diagnosis and early conservative management are essential with this particular injury. In the absence of an accurate diagnosis or sufficiently aggressive treatment, I have found the fracture may not go on to complete healing or may eventually progress to a delayed union at four months, non-union fracture at six months or osteochondrosis with possible avascular necrosis.
The treatment plan may require additional months of immobilization or offloading as well as communication with the patient about adherence. Proper treatment includes six weeks of below-knee casting followed by another six weeks of protection i. The orthotic will help prevent injury to the uninjured remaining sesamoid as well as further damage to the undersurface of the metatarsal head.
It will also help in preventing compensation to the lateral aspect of the rearfoot and forefoot. In addition to offloading, other remedies may include the use of bone stimulation or platelet rich plasma in order to stimulate osteogenesis. After exhausting all conservative measures after a prescribed period of time, surgical intervention may be indicated with the excision of the sesamoid non-union fracture.
Intraoperative protection of the first MPJ support structures is essential. Again, the postoperative use of orthotics is imperative to provide for normal length of the flexor hallucis longus and brevis tendons, and assist in preventing the formation of hallux abductovalgus after a tibial sesamoid excision.
Acute sesamoid fracture. This fracture occurs in dancers, basketball players, volleyball players and those playing other sports in which increased load from a height creates compression and stress to the sesamoid. One can recognize this injury on plain radiographs because of the sharply defined edges of the fragments with the contours being serrated. These fractures are more frequent in the tibial sesamoid and have a transverse compression appearance.
An absence of similar radiographic findings in plain films of the contralateral limb is imperative to define the acute stress fracture. Surgical excision is the remedy for fractures that are widely displaced and do not respond to conservative care. Osteochondritis dissecans. This condition can occur initially after trauma or after a repetitive stress injury and initial stress fracture. The most common cause of this injury is trauma.
In the event of trauma, vascular disruption occurs. Once there is a fracture to the sesamoid bone, the blood supply is interrupted and can often lead to avascular necrosis. Due to the loss of integrity and functional support of the sesamoid, surgical excision is the most likely remedy. Chondromalacia of the sesamoid. This happens as a result of continual synovitis. When chronic synovitis of the first MPJ occurs, fibrosis will develop, surrounding the sesamoid apparatus to the metatarsal head and the plantar capsule.
Consequently, the sesamoids will not be able to slide back and forth with motion of the flexor tendon. As a result, there will be a decreased range of motion of the joint, creating a functional hallux limitus and eventually a hallux rigidus. This can subsequently lead to a narrowing of the joint space and ultimately early degenerative joint disease. These modalities can be successful and help avoid the need for surgical intervention.
By employing this early and proactive treatment plan, the athlete may be able to return to action with limited symptoms, restoration of normal gait and little or no sequelae. The injury is most common when a foot that is fixed in equinus experiences an axial load. It usually occurs when the first MPJ extends beyond its normal range.
A turf toe will cause an immediate, sharp pain and swelling with limited range of motion of the joint. Turf toe may result in an injury to the soft tissue attached to the sesamoid or a fracture of the sesamoid. The typical scenario, which occurs often in football lineman, involves the fixation of the forefoot on the ground with dorsiflexed hyperextension of the first MPJ.
Turf toe most frequently occurs in football players but it can occur in athletes in other sports basketball, soccer, rugby, tennis, lacrosse. Research has shown that as many as 50 percent of athletes with turf toe injuries will have persistent symptoms after five years.
This can result in possible long-term sequelae including hallux rigidus, hallux valgus, cocked hallux and failure to regain push-off strength. This usually correlates to a severe articular injury. Ultimately, this will impair the performance of the athlete and lead to compensation of the forefoot. How Playing Surfaces Affect Turf Toe Incidence The hardness of artificial turf is reportedly a factor in the increased incidence of turf toe injuries. Clanton and colleagues showed there was no significant change in the incidence of turf toe injuries documented on the different artificial surfaces between and In a study of 80 professional football players, Rodeo and coworkers found that 45 percent experienced a turf toe injury.
Athletes prefer lightweight, flexible shoes, which afford little structural support. This can put the competitive athlete at considerable risk for hyperextension injury to the first MPJ, particularly on harder playing surfaces. Preseason screening of the athletes with a cursory biomechanical evaluation and gait analysis can help predict which players may be at risk for experiencing a turf toe injury. When it comes to those athletes with restricted dorsiflexion of the first MPJ and at the ankle joint, clinicians should emphasize a more supportive, stiffer shoe and a prescription orthotic to allow for enhanced propulsion and prevent injury.
Clinically, a patient with a Grade 1 injury will present with localized plantar or medial tenderness, mild edema and no visible ecchymosis. The patient will be able to bear weight and there is little change in the range of motion or strength. Typically, radiographs will be normal and an MRI evaluation will demonstrate an intact capsular integrity with mild soft tissue edema. Grade 2 injuries are more moderate in severity.
They represent partial tears of the capsuloligamentous structures, most often the sesamoid phalangeal and MPJ ligaments. The medial collateral ligament of the MPJ is commonly involved. Clinically, patients will present with a more diffuse and intense tenderness as well as mild to moderate edema with ecchymosis on the plantar and medial surface of the first MPJ. These injuries typically have varying levels of disability. There is restricted range of motion of the MPJ with severe pain, and antalgic gait with weightbearing.
Symptoms are typically progressive. Radiographs may appear normal with the sesamoid bones lying in the normal position. An MRI demonstrates moderate soft tissue edema extending through the plantar plate, indicating a partial thickness disruption. Grade 3 injuries are the most severe type of turf toe injury. This stage describes severe acute injuries with plantar capsuloligamentous disruption or the lasting chronic effects of a capsuloligamentous injury.
Clinically, patients will present with severe and diffuse tenderness. There is often marked swelling accompanied by moderate to severe ecchymosis to the MPJ with an acute injury.
Pain is often so severe that patients are unable to bear weight, which is significant for the high performance athlete. Radiographs may demonstrate proximal migration of sesamoids, compression fractures, asymmetric lateral, medial or dorsal subluxation, or capsular avulsion fragments or capsular avulsion.
Often, joint subluxation or deviation may also be apparent on radiographic stress views. In some cases, dislocation of the MPJ may occur. An MRI typically will demonstrate complete disruption of the plantar plate as well as any other associated injuries to the capsuloligamentous structures. Place the foot in a cast or removable walking cast. Crutches may prevent placing weight on the foot. Oral medications. Nonsteroidal anti-inflammatory drugs such as ibuprofen are often helpful in reducing the pain and inflammation.
Physical therapy. The rehabilitation period following immobilization sometimes includes physical therapy, such as exercises range of motion, strengthening, and conditioning and ultrasound therapy. Steroid injections.
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