Hammertoe

What is Hammertoe?

Hammertoes are among the most frequent foot deformities. They occur when the balance between the weaker intrinsic muscles and the stronger extrinsic muscles around the joints of the lesser toes is disrupted. A hammertoe is a deformity where the toe joints are flexed and can be categorized into the typical hammertoe, a mallet toe or a claw toe. The smaller toes play a crucial role in foot balance and pressure distribution, and any deformities can cause changes in walking, toe misalignment, callus growth, and pain.

Treatment options are abundant and typically start with simple measures such as wearing wider shoes, using toe pads, and employing orthotics properly. If these methods don’t relieve the pain and the deformity worsens, surgery might be beneficial. The surgical approach will vary, depending on the rigidity of the deformity. Therefore, it’s crucial to properly evaluate the patient’s condition to ensure long-lasting relief from the deformity.

The imbalance between the weaker and stronger muscles in your foot can result in toe deformities. When the stronger extrinsic muscles overpower the weaker intrinsic ones, the result can be an extended toe joint and potential hyperextension. The main function of the Extensor digitorum longus muscle (EDL) is to move the foot upward during walking. It splits into four parts, each going to one of the lesser toes, and then divides again over the primary toe joint.

Extensor digitorum brevis (EDB) has three parts and combines with EDL at the level of the big toe joint to form what is known as the extensor hood apparatus. The pull of these two muscles primarily moves the big toe joint upwards while minimally moving the smaller toe joints. On the other hand, the Flexor digitorum longus (FDL) splits into four parts that insert onto the smaller toes and bend them, resulting in bent smaller toe joints.

Instability in the MTPJ joints is commonly seen in patients with toe deformities. Key ligaments stabilize this joint. If these ligaments weaken or rupture, it can result in instability of the big toe joint. A rupture of these ligaments can also lead to dislocation, and an injury to the lateral ligaments may result in a sideways drifting toe with a potential inward or outward rotation. This can lead to a ‘cross-over deformity.’

What Causes Hammertoe?

Hammertoe deformity can happen due to a variety of reasons. It can either be something a person is born with (congenital) or acquired over time, usually due to an issue with how the foot functions biomechanically. Factors that contribute to the development of hammertoe, a common foot deformity, include:

• Neuromuscular conditions, or problems with nerves and muscles
• Diabetes
• Inflammatory arthropathies, or joint diseases
• Wearing shoes that don’t fit right or high heels
• Intrinsic muscle imbalance, or when the strength of the muscles in the foot do not balance out
• Hallux valgus, also known as a bunion
• Long metatarsals, or long bones in the foot
• Pes planus, also known as flat feet

Risk Factors and Frequency for Hammertoe

Lesser toe deformities, which affect the smaller toes on your foot, are quite common. They can impact up to 20% of people and are often found in women and older individuals. These toe problems also tend to run in families. Having a specific existing foot condition, such as a big toe that deviates towards the other toes (hallux abductovalgus), a toe that is longer than usual, or a flat foot (pes planus) can increase the likelihood of having these smaller toe deformities.

Signs and Symptoms of Hammertoe

A hammertoe is usually described as a chronic issue where the affected toe becomes increasingly bent. This might result in the toe becoming red and painful. People suffering from this problem generally have long-term pain which gets worse when they walk or wear shoes. As the toe gets more deformed, the pain also gets progressively worse. If you look at the skin around the bent toe, you might observe blisters, hardened skin, sores, and skin irritation because of the extra pressure on these areas. Some people also experience pain under the ball of their foot, and this typically happens when the metatarsophalangeal joint (MTPJ) is hyperextended, out of place, or dislocated.

During a physical examination, the doctor should check the patient’s foot movement to identify potential causes of the hammertoe and any other associated deformities like bunions. The doctor should assess the patient’s feet both while they’re standing up and sitting down as some deformities can’t be properly understood if the patient is seated. The medical examination will likely be split into checking the foot when weight is applied and when it’s not. The doctor should conduct a Lachman test to check the stability of the MTPJ and record the flexibility of all deformities. The doctor should also examine the patient’s nervous system and blood circulation, which includes checking their pulses.

Flexible hammertoes are usually visible when the patient is standing and can be manually corrected when the foot is in a relaxed, neutral position. On the other hand, rigid deformities can’t be fixed this way. The doctor should attempt to manually correct the toe to help determine the best treatment options. The MTPJ should be tested for its range and quality of movement. If the joints of the metatarsal head are more tender and unstable when felt, it might require a different treatment than if the patient was dealing with a standalone hammertoe problem.

Testing for Hammertoe

To thoroughly examine hammertoes, it’s important to use imaging techniques.

X-rays

Taking an X-ray from different angles while you’re standing can be very useful in studying hammertoe deformities. These X-rays can help doctors identify muscle contractions, an important sign of hammertoe known as the “gun barrel.” They also allow doctors to check the length of your bones in your foot, spot conditions such as bunions or abnormal positions of the bones in your feet, and evaluate how your bones align in your foot. This is particularly handy when getting ready for surgery. A special method using a line drawn on the X-ray image is used to determine if the affected toe is longer than it should be.

MRI Scans

An MRI scan may be ordered if there’s a reason to believe there might be a tear in the structure that supports the bottom of your foot. This advanced imaging technique can also help catch other issues like a lack of blood supply to the bone in the foot (most commonly the second bone), or damage to the joint cushioning. If you have health issues like diabetes, nerve damage in the feet or poor blood circulation, further noninvasive tests might be needed to ensure proper healing evaluation.

Treatment Options for Hammertoe

Hammertoe deformities can cause severe discomfort and greatly affect a person’s life quality. Surgery to correct hammertoes is one of the most common surgeries conducted on the front part of the foot.

Non-surgical Treatment

Before deciding on surgery, doctors usually try non-surgical treatments aimed at relieving pressure on specific parts of the foot and toe. It is recommended for people with less severe deformities to use insoles or orthotics and roomy shoes to accommodate the deformity and ease the pain. High heel shoes are not recommended as they can add extra pressure to the front of the foot. Padding or shaving painful calluses might also help alleviate discomfort, and flexible deformities can be treated by strapping or taping to improve alignment. However, these methods are temporary solutions and do not permanently correct the deformity.

Surgical Treatment

When foot deformities become permanent and painful, surgery might be necessary. This usually involves adjusting the toe’s length to balance out the forces from various muscles. The choice between non-surgical care and surgical intervention depends on the degree of the deformity and its impact on the patient’s life.

Surgeries for hammertoe deformities should address and correct the deformity at all joints of the affected toe. The most common surgical techniques include the resection of joint parts or fusion of the joints, depending on the severity of the condition. Surgeries for flexible hammertoes often involve releasing some soft tissue to maintain the toe’s structural stability.

If there is instability in the joint at the base of the toe and surgery is warranted, this should be addressed during the procedure. This could involve an osteotomy to correct the affected foot bone and/or a plantar plate repair. A plantar plate rupture can be diagnosed by the Lachman test, a physical examination technique. If the toe deviates dorsally more than usual, it indicates a plantar plate rupture or insufficiency.

Several other surgical methods, including toe shortening and tendon transfers, can be used to treat hammertoes. However, the specific surgical technique used is chosen on a case-by-case basis, considering the patient’s specific deformity and its severity.

What else can Hammertoe be?

Over the years, there’s been some confusion about the difference between hammertoes and claw toes, probably because they’re usually treated the same way. Despite this, some characteristics can help distinguish these conditions:

• Claw toe is usually recognized as a condition where the middle and end joints of the toe are bent downward while the joint connecting the toe to the foot is bent upward. Often, claw toes are more severe, usually involve multiple toes on both feet, and are often related to neuromuscular conditions. Claw toes frequently appear in conjunction with ‘cavus foot’ – a high-arched foot.
• On the other hand, hammertoe generally refers to a bending or curling downward of the middle joint in the toe. Unlike claw toes, hammertoes can happen in just one toe – most commonly the second one. In this condition, the last joint of the toe might be bent or straight, and the base joint may also be bent.

There’s another variant of toe conditions – mallet toe, where the deformity is isolated to the last joint of the toe, which is bent inward.

Other conditions that might cause discomfort or pain in the toe area include turf toe, sesamoiditis (inflammation of the tiny bones in the foot), gout, growth irregularity in the big toe bone, degenerative joint condition known as osteochondritis dissecans, metatarsalgia (pain in the ball of the foot), and stress fractures in the foot bones.

What to expect with Hammertoe

Hammertoe deformity is a condition that gradually worsens over time. However, the overall outlook for patients with a hammertoe deformity is positive. After the patient’s condition has been assessed, non-invasive treatment should be initiated. If the patient doesn’t see an improvement in pain or function, surgery may be an option. The time it takes to recover from the surgery varies depending on the specific procedure, the specific techniques used, and the preference of the surgeon.

The common post-surgery process usually involves the patient putting partial weight on their heel while wearing a postoperative shoe for 2-6 weeks, followed by a transition into a rigid athletic shoe. The recovery period might be longer for smokers or individuals with diabetes. Surgery-related complications can occur, and the risk and types of possible complications depend on the surgical method used. Typical complications after surgery can include infections, non-union (when the bone fails to heal), hematoma (a collection of blood outside of the blood vessels) numbness, and a recurrence of the deformity.

It’s worth noting that the failure and repeat surgery rates for toe deformities are relatively high, with rates going up to 10%. The second toe appears to be more likely to have issues compared to the third and fourth toes. Patients who had a larger deformity across their toe before surgery had a higher failure rate than those with a deformity mainly in the upward or downward orientation. Additionally, performing a concurrent surgery to address a deviated first toe has been linked to a nearly 50% decrease in the recurrence of hammertoe. Recurrence may occur if the flexor tendon (a tendon that helps the toes curl) is too tight or if not enough bone has been removed during the surgery. However, care should be taken as removing too much bone could lead to a flail toe, which is a toe that lacks stability.

Possible Complications When Diagnosed with Hammertoe

Hammertoes usually start as mild deformities and get worse over time. This can lead to problems like pain, imbalance while walking, a decrease in quality of life and skin changes such as callouses, corns, and blisters. There can also be complications if a person has surgery to correct the hammertoe deformity, including but not limited to:

• Nonunion (bones do not heal together)
• Malunion (bones heal in an incorrect position)
• Avascular necrosis (bone death due to lack of blood supply)
• Metatarsalgia (pain in the ball of the foot)
• Malalignment (bones become misaligned)
• Infection
• Numbness
• PIP joint instability (flail toe or unstable toe)
• Pain
• Recurrent deformity (the hammertoe comes back)
• Stiffness
• Vascular impairment (problems with blood vessels)
• Chronic edema (persistent swelling)
• Mallet toe (another kind of toe deformity)

Preventing Hammertoe

Hammertoes are among the most common foot deformities. These are characterized by the bending of the joints between the toe bones. This kind of deformity can lead to changes in walking style, the formation of hard skin or calluses, and pain. To manage hammertoe, the use of shoes with a wider space for the toes, padding for the toes, taping, and specially designed shoe inserts (orthotics) are recommended. The type of surgery needed to correct the issue will depend on whether the hammertoe is flexible or rigid, or if there is instability in the joint at the base of the toe. Most patients are able to resume their usual activities once their doctor gives them the go-ahead.