Sesamoid Problems

Cure Arthritis Naturally

Beat Arthritis Naturally

Get Instant Access

In the vast majority of the population, there are two small sesamoid bones under the first metatarsal head. They are incorporated into the medial and lateral heads of the flexor hallucis brevis tendons and are termed the tibial and fibular sesamoids. Sesamoid problems are more common in women, possibly due to the greater degree of dorsiflexion present normally in their first metatarsophalangeal joints and more common in the tibial sesamoid. Up to 50% of body weight may be carried by the first metatarsal head, and the sesamoids receive even more stress. The sesamoids are involved in push off and serve as an integral part of forefoot function. The sesamoid complex includes the two sesamoids, the interosseous ligament, the flexor brevis tendons, the joint articulation, and the flexor hallucis longus. Problems may range from sesamoiditis to stress fracture, acute fracture, osteonecrosis, and fragmentation. In the older population, degenerative arthritis may involve the sesamoid-metatarsal articulation with loss of cartilage and overgrowth of the sesamoid. Sports that involve dorsiflexion of the first ray and repetitive impact such as dance, soccer, and running are most likely to produce problems.

Sesamoiditis is a fairly nebulous term. It does not necessarily mean that actual inflammatory tissue is present. Some patients will have true inflammation with swelling and joint effusion while others have only pain. It is generally a term used for sesamoid pain without apparent fracture or necrosis.

Clinically patients with sesamoid problems report the insidious onset of pain under the first metatarsal head, sometimes accompanied by swelling. Acute fractures are uncommon and usually associated with an acute dorsiflexion event. Again, harder surfaces generally increase the pain and softer surfaces improve it. Some patients will describe burning or lightning type pain, likely from local irritation of the digital nerves as they run close to the sesamoids.17

Physical examination should include range of motion of the great toe, identification of effusion, palpation, examination for calluses, and neurovascular status. Recently, a new provocative test was described for evaluation of sesamoid pain.18 The test is performed by dorsiflexing the toe to its fullest extent, placing the thumb firmly against the proximal pole of the sesamoid and plantar flexing the toe. Reproduction of symptoms by this test indicates a sesamoid problem. Examination of the digital nerves should be performed; a Tinel's sign may indicate nerve injury or entrapment. In order to differentiate sesamoid pain from flexor hallucis longus tendonitis, this tendon should be tested by resisting active plantarflexion of the distal interphalangeal joint.

Radiographs and other studies are often helpful in identifying fracture, necrosis, arthritis, and fragmentation of the sesamoids. All patients should have radiographs including an axial view and weight-bearing anteroposterior and lateral views of the sesamoids (Fig. 71-7). They should be evaluated for location, size, contour, and presence of fractures. Bipartite sesamoids are relatively common, and should not be confused with fractures. Bipartite sesamoids fragments have rounded outlines. When in doubt, a radiograph of the opposite foot can be helpful as bipartite sesamoids are frequently (but not exclusively) bilateral. In the case in which a stress fracture or necrosis is suspected, a bone scan with pinhole collimation or magnetic resonance imaging can be very helpful, especially when plain radiographs are normal (Fig. 71-8). Rarely, computed tomography is needed to evaluate the sesamoid-metatarsal articulation for degenerative changes or bony overgrowth.17

Treatment of most sesamoid problems is conservative. Rest, activity modification, and shoe change are the first steps in treatment. A dancer's pad is very useful and inexpensive (Fig. 71-9). As sesamoid pain is common in dancers, these pads are designed to even fit into ballet slippers. The pads should be placed in the athlete's training shoes. For more prolonged symptoms, a durable custom orthotic can be constructed with this type of padding. In some cases, especially those with swelling or joint effusion, an intra-articular steroid injection may be very helpful. Physical therapy also plays an important role. Ultrasonography, heel cord stretching, taping, and strengthening of the flexor brevis muscles should be ordered.

For degenerative arthritis of the sesamoid, orthotic management is usually sufficient with the addition of steroid injection if needed. In cases in which overgrowth of one sesamoid leads to a prominence causing an intractable keratosis, shaving of the sesamoid is helpful.

In acute fractures or symptomatic stress fractures, 6 to 8 weeks of rest and cast (fiberglass or functional brace) followed by orthotic wear, taping, and physical therapy are often very successful. In the rare case of a symptomatic nonunion, the sesamoid should be preserved if possible. Bone grafting of the

How Radiograph Tibial Sesamoid Sesamoid Axial Bipartite Medial Sesamoid

Figure 71-10 Sesamoid fracture nonunion that healed after bone graft.

A, Anteroposterior radiograph of a tibial sesamoid fracture nonunion.

B, Healed results after bone grafting.

tibial sesamoid has been described, and reports are encourag-ing.19 The author has had three patients in the past several years who have improved with this procedure and returned to their work or sport (Fig. 71-10). If the proximal pole of the nonunion is small and bone grafting is not possible, then excision of this fragment with preservation of the tendon continuity is indicated. In even rarer cases of necrosis, fragmentation, or simply chronic unremitting pain, the sesamoid may be excised.20 This surgery has a significant rate of complications including hallux valgus, hallux varus, clawing, and neurogenic pain. The sesamoids play a very important role in push off and should only be excised as a last resort.

Sesamoid Pads
Figure 71-9 Dancer's pad for sesamoid pain.

Figure 71-10 Sesamoid fracture nonunion that healed after bone graft.

A, Anteroposterior radiograph of a tibial sesamoid fracture nonunion.

B, Healed results after bone grafting.

Was this article helpful?

0 0
Arthritis Relief Now

Arthritis Relief Now

When you hear the word arthritis, images of painful hands and joints comes into play. Few people fully understand arthritis and this guide is dedicated to anyone suffering with this chronic condition and wants relief now.

Get My Free Ebook

Post a comment