Brachydactyly

Brachydactyly is a rare congenital condition characterized by unusually short fingers or toes due to underdeveloped bones (1). The term comes from the Greek words brachy (short) and dactylos (finger). While it can occur as an isolated condition, brachydactyly is sometimes associated with genetic syndromes or other developmental abnormalities. The severity and presentation vary widely, some people may have only one short digit, while others may experience multiple shortened fingers or toes.

In many cases, brachydactyly does not cause functional problems and is primarily a cosmetic concern. However, when severe, it can affect hand function, grip, walking, or balance (1). Understanding the condition’s symptoms, causes, and treatment options is important for both patients and families.

Symptoms

The primary symptom of brachydactyly is the shortening of fingers or toes due to abnormal bone development (1). Symptoms can differ depending on the type and severity of the condition:

• Shortened digits: The most visible feature is one or more short fingers or toes.
• Uneven finger/toe length: Some digits may appear significantly shorter than others.
• Hand or foot shape changes: In moderate to severe cases, the hands or feet may look misshapen.
• Functional issues: Severe brachydactyly may cause difficulty in grasping objects, writing, or walking.
• Associated anomalies: In syndromic cases, brachydactyly may occur alongside hearing loss, heart defects, or other developmental problems.

Most individuals with mild forms have no pain or functional limitations, while others may require assistance with daily tasks (2).

Causes

Brachydactyly is primarily a genetic condition caused by variations or mutations in specific genes that regulate bone growth and development (1). The following factors contribute to its occurrence:

• Genetic mutations: Inherited mutations affecting bone growth can result in shortened digits.
• Autosomal dominant inheritance: Brachydactyly often follows this inheritance pattern, meaning a single copy of the altered gene from one parent is enough to cause the condition.
• Syndromic associations: It can occur as part of syndromes like Down syndrome, Rubinstein-Taybi syndrome, or Turner syndrome.
• Sporadic cases: Sometimes, brachydactyly appears without a family history, due to spontaneous mutations.
• Environmental factors (rare): Though uncommon, reduced blood flow during fetal development may contribute to abnormal bone growth in the limbs.

Risk Factors

Certain factors increase the likelihood of developing brachydactyly:

• Family history: The strongest risk factor. If one parent has brachydactyly, there is a significant chance it will be passed on to children (2).
• Genetic syndromes: Conditions such as Down syndrome, Albright hereditary osteodystrophy, and others often feature brachydactyly as a symptom.
• Consanguinity: Marriages between close relatives increase the risk of inheriting genetic conditions.
• Gender: While brachydactyly can affect both genders, some studies suggest it may be slightly more common in females depending on the subtype.

Diagnosis

Brachydactyly is usually diagnosed in childhood or even at birth through a physical examination. Doctors assess the shape and length of fingers or toes, followed by imaging and genetic evaluation if needed (2).

Diagnostic methods include

• Clinical examination: Observing digit length, hand shape, and symmetry.
• X-rays: Imaging reveals underdeveloped or missing bones in the hands and feet.
• Genetic testing: Identifies specific mutations or syndromes linked to the condition.
• Family history analysis: Helps confirm inheritance patterns.

In syndromic cases, doctors may also perform heart scans, hearing tests, or other evaluations to rule out additional complications.

Treatment Options

Treatment for brachydactyly depends on severity, symptoms, and associated conditions. While mild cases often require no intervention, more complex cases may need medical or surgical treatment (3).

• Observation and reassurance: For individuals with no functional impairment, treatment may not be necessary. Cosmetic concerns can be managed with counseling and support.
• Physical therapy: Helps improve strength, flexibility, and coordination of hands and feet. Children may benefit from occupational therapy to adapt to daily tasks.
• Orthotic devices: Shoe inserts or hand splints can aid individuals with walking or gripping difficulties.
• Surgical options: In severe cases, reconstructive or corrective surgery may be performed. Techniques include bone lengthening, grafting, or joint realignment. These procedures aim to improve both function and appearance.
• Treatment of associated conditions: If brachydactyly is part of a syndrome, treatment may also involve managing heart defects, hormonal imbalances, or developmental delays.

Living With or Prevention

Living with brachydactyly largely depends on the severity of the condition. Most people with mild forms lead completely normal lives without functional limitations. Coping strategies and support can include

• Adapting daily tasks: Using modified writing tools or gripping aids if necessary.
• Psychological support: Addressing self-esteem or body image concerns, especially in children and adolescents.
• Regular medical monitoring: For syndromic cases, ongoing care may be necessary to manage associated complications.

Prevention: Since brachydactyly is primarily genetic, it cannot usually be prevented (3). However, certain steps can help in managing risks

• Genetic counseling: Families with a history of brachydactyly can benefit from counseling before planning children to understand inheritance risks.
• Prenatal testing: Ultrasound and genetic tests during pregnancy may detect brachydactyly early.
• Early intervention: Detecting the condition at birth allows for timely therapy and support if functional issues arise.

References

1. Shao J, Liu Y, Zhao S, Sun W, Zhan J, Cao L. A novel variant in the ROR2 gene underlying brachydactyly type B: a case report. BMC Pediatr. 2022 Sep 5;22(1):528. doi: 10.1186/s12887-022-03564-z. PMID: 36064339; PMCID: PMC9446770.
2. AbuHaweeleh MN, Ahmed MB, Al-Mohannadi FS, Mohamed MD, AlSherawi A. Brachydactyly type B: a rare case report and literature review. J Surg Case Rep. 2024 May 31;2024(5):rjae376. doi: 10.1093/jscr/rjae376. PMID: 38826861; PMCID: PMC11141291.
3. Pereda A, Garin I, Garcia-Barcina M, Gener B, Beristain E, Ibañez AM, Perez de Nanclares G. Brachydactyly E: isolated or as a feature of a syndrome. Orphanet J Rare Dis. 2013 Sep 12;8:141. doi: 10.1186/1750-1172-8-141. PMID: 24028571; PMCID: PMC3848564.