Overview
Split hand, unilateral (also called unilateral ectrodactyly or lobster claw hand on one side) is a rare congenital limb malformation in which one hand has missing central fingers, creating a deep cleft or split in the middle of the hand. The condition affects only one hand, unlike bilateral forms that involve both hands or hands and feet. The hand may appear to have a V-shaped gap where the middle fingers should be, and the remaining fingers may be fused or abnormally shaped. This condition is present at birth and is typically an isolated finding, meaning it occurs on its own without other major health problems in most cases. The severity can vary widely. Some individuals have only a mild cleft with minor finger differences, while others may have significant absence of fingers and changes in hand structure. Despite the visible difference, many people with unilateral split hand retain good hand function, especially with early therapy and, in some cases, surgical reconstruction. Note: This entry is classified as 'OBSOLETE' in the Orphanet database, meaning it may have been reclassified or merged into a broader category of split hand/foot malformations (ectrodactyly). Patients and families should discuss the most current classification with their geneticist. Treatment is primarily supportive and may include occupational therapy to maximize hand function, prosthetic devices, and reconstructive surgery depending on the severity. Genetic counseling is recommended to understand recurrence risks.
Also known as:
Key symptoms:
Missing central fingers on one handDeep cleft or split in the middle of the handV-shaped or lobster claw appearance of the handFused fingers on the affected handShortened or underdeveloped fingersReduced grip strength in the affected handAbnormally shaped remaining fingersDifficulty with fine motor tasks using the affected hand
Variable
Can be inherited in different ways depending on the underlying gene
Neonatal
Begins at or shortly after birth (first 4 weeks)
Treatments
No FDA-approved treatments are currently listed for OBSOLETE: Split hand, unilateral.
View clinical trials →Clinical Trials
View all trials with filters →No actively recruiting trials found for OBSOLETE: Split hand, unilateral at this time.
New trials open frequently. Follow this disease to get notified.
Specialists
View all specialists →No specialists are currently listed for OBSOLETE: Split hand, unilateral.
Treatment Centers
8 centersBaylor College of Medicine Rare Disease Center ↗
Baylor College of Medicine
📍 Houston, TX
🏥 NORDStanford Medicine Rare Disease Center ↗
Stanford Medicine
📍 Stanford, CA
🔬 UDNNIH Clinical Center Undiagnosed Diseases Program ↗
National Institutes of Health
📍 Bethesda, MD
🔬 UDNUCLA UDN Clinical Site ↗
UCLA Health
📍 Los Angeles, CA
🔬 UDNBaylor College of Medicine UDN Clinical Site ↗
Baylor College of Medicine
📍 Houston, TX
🔬 UDNHarvard/MGH UDN Clinical Site ↗
Massachusetts General Hospital
📍 Boston, MA
🏥 NORDMayo Clinic Center for Individualized Medicine ↗
Mayo Clinic
📍 Rochester, MN
👤 Mayo Clinic Center for Individualized Medicine
🏥 NORDUCLA Rare Disease Day Program ↗
UCLA Health
📍 Los Angeles, CA
Travel Grants
No travel grants are currently matched to OBSOLETE: Split hand, unilateral.
Community
No community posts yet. Be the first to share your experience with OBSOLETE: Split hand, unilateral.
Start the conversation →Latest news about OBSOLETE: Split hand, unilateral
No recent news articles for OBSOLETE: Split hand, unilateral.
Follow this condition to be notified when news becomes available.
Caregiver Resources
NORD Caregiver Resources
Support, advocacy, and financial assistance for caregivers of rare disease patients.
Mental Health Support
Rare disease caregiving can be isolating. Connect with counseling and peer support.
Family & Caregiver Grants
Financial assistance programs specifically for caregivers of rare disease patients.
Social Security Disability
Learn how rare disease patients may qualify for SSDI/SSI benefits.
Questions for your doctor
Bring these to your next appointment
- Q1.Is my child's split hand isolated, or could it be part of a broader genetic syndrome?,Should we pursue genetic testing, and what would the results mean for our family?,Would surgery improve hand function or appearance, and when is the best time for it?,What kind of occupational therapy is recommended, and how often?,What is the chance that future children could also be affected?,Are there adaptive devices that could help with daily tasks?,Can you refer us to a support group for families of children with limb differences?
Common questions about OBSOLETE: Split hand, unilateral
What is OBSOLETE: Split hand, unilateral?
Split hand, unilateral (also called unilateral ectrodactyly or lobster claw hand on one side) is a rare congenital limb malformation in which one hand has missing central fingers, creating a deep cleft or split in the middle of the hand. The condition affects only one hand, unlike bilateral forms that involve both hands or hands and feet. The hand may appear to have a V-shaped gap where the middle fingers should be, and the remaining fingers may be fused or abnormally shaped. This condition is present at birth and is typically an isolated finding, meaning it occurs on its own without other maj
At what age does OBSOLETE: Split hand, unilateral typically begin?
Typical onset of OBSOLETE: Split hand, unilateral is neonatal. Age of onset can vary across affected individuals.