Distal Arthrogryposis (DA): Clinical Features and Management
Distal arthrogryposis (DA) is a group of genetic disorders characterized by congenital contractures primarily affecting the hands and feet, with autosomal dominant inheritance being the most common pattern. 1
Clinical Features
Key Characteristics
- Congenital contractures predominantly affecting distal joints (hands and feet)
- Mostly inherited in an autosomal dominant fashion
- Second most common type of arthrogryposis after amyoplasia
Common Hand and Foot Deformities
- Camptodactyly (flexion contractures of fingers)
- Thumb-in-palm deformity
- Windblown hand deformity
- Ulnar deviation of fingers
- Club feet
- Sandal gaps between toes
- Shortened 1st and 5th toes 2, 3
Classification and Subtypes
DA is classified into multiple subtypes based on specific features:
DA Type 5 (DA5):
- Distinguished by presence of ptosis and ophthalmoplegia
- Additional features include:
- Restricted ocular movements
- Distinctive facial appearance with deep-set eyes
- Restrictive lung disease (in some cases)
- Metacarpal and metatarsal synostosis (in some cases) 3
- May present with very mild musculoskeletal phenotype, sometimes without obvious distal joint involvement 4
DA Type 2B:
- Characterized by distal joint contractures
- Ptosis and ophthalmoplegia
- Unusual hair loss pattern
- Conical teeth 5
Associated Findings
- Short stature
- Firm muscles
- Stiff spine with lumbar hyperlordosis
- Generalized mild limitation of large joints
- External rotation of the hips
- Decreased flexion palmar creases
- Brachydactyly
- Syndactyly 4, 2
Ocular Manifestations
- Ptosis (often unilateral)
- Exophoria
- Ophthalmoplegia
- Juvenile macular dystrophy (in some cases)
- Abnormal photopic and scotopic responses on electroretinogram
- Optic disk excavation (in some cases) 4, 3
Diagnostic Approach
Clinical Evaluation
- Thorough assessment of joint contractures, particularly in hands and feet
- Evaluation of ocular movements and ptosis
- Assessment of facial features
- Examination for associated skeletal abnormalities
Genetic Testing
- Whole-exome sequencing can identify causative mutations
- Known genetic causes include:
Management
Treatment Principles
- Early intervention leads to better outcomes
- Individualized approach based on specific deformities
- Multidisciplinary team involvement
Non-operative Management
- Initial approach for most deformities
- Physical and occupational therapy
- Splinting and casting
Surgical Management
When non-operative treatment fails to provide adequate improvement:
- Release of soft-tissue contractures
- Rebalancing of muscle forces
- Bony correction when necessary
Long-term Follow-up
- Regular monitoring for progression of deformities
- Assessment of functional outcomes
- Evaluation for associated conditions (respiratory, ocular)
Prognosis
Despite physical limitations, affected individuals can maintain active lifestyles with appropriate interventions 5. The phenotypic expression can be highly variable even within the same family, with some members showing more severe manifestations than others 2, 3.
Research Needs
Current literature on DA is limited, with no established consensus or gold standard for treatment. Long-term multicenter studies are needed to standardize treatment approaches and assess outcomes 1.