Viking finger, also known as Dupuytren’s contracture, is a hand deformity where the ring finger and little finger bend towards the palm and cannot be fully extended. It was nicknamed “Viking finger” because it was commonly seen in Norse warriors. Viking finger can cause significant impairment of hand function and deformity. Understanding what causes Viking finger is important for prevention and treatment.
What is Viking Finger?
Viking finger, or Dupuytren’s contracture, is characterized by a thickening and shortening of the palmar fascia in the hand. The palmar fascia is a thin sheet of connective tissue that covers the tendons and muscles in the palm. As Viking finger progresses, nodules and cords form under the skin and cause the fingers to bend towards the palm. The ring finger and little finger are most commonly affected.
In the early stages, Viking finger may only cause some tightening of the palm and fingers. As it progresses, the bending of the affected fingers becomes more severe until the fingers are permanently flexed with contractures. This impairs hand function for gripping and grasping objects. Advanced cases of Viking finger can cause the fingers to press into the palm.
What Causes Viking Finger?
The exact cause of Viking finger is unknown, but it appears to be multi-factorial:
Genetic Factors
Viking finger often runs in families, so genetics plays a role. Around 40% of people with Dupuytren’s contracture have a family history of the condition. The inheritance pattern suggests an autosomal dominant transmission, meaning only one copy of a defective gene is needed to develop the condition. However, no single “Dupuytren’s gene” has been identified. It is likely caused by variations in multiple genes that regulate connective tissue.
Ethnic Factors
Certain ethnic groups have higher rates of Dupuytren’s contracture. People of Northern European descent, especially those from Scotland, Iceland, and Norway, have the highest prevalence. This correlates with the Vikings who were originally from Scandinavia and Northern Europe. Dupuytren’s contracture is less common in African Americans and Asians.
Age
The risk of developing Viking finger increases significantly with age. It rarely occurs in people under 40 years old. The prevalence rises to 12% in people aged 55 years and up to 29% in people aged 75 years and older. This suggests aging processes contribute to changes in the palmar fascia over time.
Sex
Men are 3-4 times more likely to develop Viking finger than women. Male hormones may play a role, but the reason for this difference between sexes is not fully understood.
Diabetes
People with diabetes have a significantly higher risk of Viking finger. Up to 32% of people with diabetes develop Dupuytren’s contracture. High blood sugar levels in diabetes can cause tissue damage through advanced glycation end products (AGEs). AGEs may lead to thickening and shortening of collagen fibers in the palmar fascia.
Smoking
Several studies show an association between smoking and increased risk of Dupuytren’s contracture. Smoking may promote tissue damage through effects on small blood vessels and inflammation. The exact mechanisms are still under investigation.
Alcohol
Heavy alcohol consumption is linked to higher rates of Viking finger. The association may be due to direct toxic effects of alcohol on connective tissue or related liver disease. However, light or moderate alcohol intake does not appear to increase risk significantly.
Manual Labor and Hand Injuries
People who do repetitive manual work and vibration exposure for prolonged periods have higher rates of Dupuytren’s contracture. Previous hand trauma such as fractures or lacerations also increase risk. This suggests repeated mechanical stress and tissue damage can trigger changes in the palmar fascia.
Anti-epileptic Medications
Certain anti-seizure medications like phenytoin have been associated with Dupuytren’s contracture. This is thought to relate to fibrotic side effects of the medications in connective tissues.
Pathophysiology
The exact mechanisms behind the development of Viking finger are complex and not fully understood. It appears to involve dysfunction in regulation of the extracellular matrix and fibroblasts in the palmar fascia.
Some key pathophysiological processes include:
Fibroblast Proliferation
An increase in fibroblasts (connective tissue cells) and myofibroblasts is seen in affected palmar fascia tissue. Myofibroblasts secrete collagen and cause palmar fascia thickening and cord formation.
Extracellular Matrix Changes
There are abnormalities in the composition of collagen, glycoproteins, and proteoglycans (protein/sugar compounds) that make up the extracellular matrix. This causes weakening and shortening of fascia tissues.
Microvascular Dysfunction
Alterations in the small blood vessels (microvasculature) in the palm are often present, which may contribute to areas of low oxygen tension and tissue damage.
Low-Grade Inflammation
Increased inflammatory mediators are found in affected palmar fascia tissue. This low-grade inflammation may drive fibroblast changes and matrix remodeling.
Metabolic Disorders
Disorders like diabetes and alcoholism create systemic metabolic abnormalities that can affect connective tissues like the palmar fascia. This may accelerate disease progression.
Mechanical Stress
Repeated manual work and trauma generates localized mechanical tension and micro-injuries in the palm. This stress may initiate the tissue changes of Dupuytren’s contracture.
Risk Factors
The major risk factors for developing Viking finger include:
Age
The risk increases significantly after age 40 and continues rising with older age.
Sex
More common in males. Males have 3-4 times higher risk than females.
Ethnicity
Northern European descent, especially Scandinavian and Celtic groups have the highest rates.
Family History
Positive family history suggests a genetic predisposition. Around 40% of patients have a family member with Dupuytren’s contracture.
Diabetes Mellitus
Long-standing diabetes accelerates disease onset and progression. The risk in diabetics is up to 32%.
Smoking
Cigarette smoking is associated with a 3-fold increased risk compared to non-smokers.
Alcohol Consumption
Heavy alcohol intake may increase risk. Light or moderate consumption does not appear to be a major risk factor.
Manual Labor
Occupations involving prolonged periods of manual work, vibration exposure, and repetitive hand stress.
Prior Hand Injury
Previous significant injuries like fractures or lacerations to the hand/fingers.
Anti-epileptic Medications
Some anti-seizure drugs like phenytoin are linked to Dupuytren’s contracture.
Clinical Presentation and Diagnosis
Viking finger has some classic signs and symptoms. Diagnosis is made based on physical examination of the hand.
Symptoms
– Tightness and stiffness in the palm and fingers
– Difficulty flattening the hand on a flat surface
– Loss of finger extension range of motion
– Fingers gradually bending into a flexed position
– Nodes or bumps in the palm
– Pitting of the skin over nodules
– Pain, numbness or tingling in advanced cases
Signs
– Thickened, tethered tissue in the palm
– Firm nodules or cords felt in the palm
– Indentations or pits over nodules
– Contractures and bent finger deformities typically affecting the ring and little fingers
– Inability to fully extend affected fingers
– Positive “table top test” – inability to flatten hand flat on a table
Diagnostic Tests
No special tests are required. Viking finger is diagnosed clinically by examination of the hands and observing the finger contractures and palmar thickening. Sometimes imaging like ultrasound or MRI may be done if the diagnosis is uncertain. Blood tests are done to check for associated conditions like diabetes or liver disease. Genetic testing is not routinely performed.
Treatment and Management
There are various treatment options for Viking finger based on the severity and impact on hand function:
Observation
Mild cases that are not progressing may simply be observed and monitored at regular intervals. No treatment is immediately required.
Splinting
Splints worn at night can help straighten bent fingers and delay contracture progression in early cases.
Collagenase Injections
Injecting collagenase enzymes into cords can weaken and rupture them, helping to straighten fingers. Often requires multiple injection sessions.
Needle Aponeurotomy
Percutaneous needle cutting of cords with a small needle to help extend fingers. Can be done repeatedly as needed.
Hand Therapy
Stretching exercises, massage and other therapies to improve hand mobility and function. Often used post-procedurally.
Surgery
Surgical removal of diseased fascia and cords (partial fasciectomy) for advanced contractures and severe impairment. Can significantly improve hand function but risks include nerve injury, infection, and recurrence.
Medications
No medications conclusively proven to prevent progression or cure Viking finger. Some emerging research on statins, steroids, and immune modulators.
Prevention
There are no definitive ways to prevent Viking finger, but the following measures may help lower risk:
– Avoid smoking
– Limit alcohol intake
– Manage diabetes and other medical conditions
– Use protective gloves for manual labor
– Avoid repetitive hand stress and trauma
– Do hand stretches and exercises
– Use night splints preventively if high risk
Prognosis
The prognosis for Viking finger depends on severity at diagnosis and treatment:
– Mild cases may stabilize without progression for many years
– Severe long-standing contractures are unlikely to fully resolve even with surgery
– Good outcomes more likely if treated early before advanced deformity
– Recurrence eventually occurs in up to 50% of surgical patients
– Hand therapy can help maximize hand function after treatment
– Does not reduce life expectancy or cause mortality by itself
– Main impacts are reduced hand mobility and dexterity
Conclusion
In summary, Viking finger is caused by changes in the palmar fascia leading to contractures, most often affecting the ring and little fingers. Exact causes are unclear but involve genetic, ethnic, age, sex, and lifestyle factors. Risk increases with Northern European ancestry, family history, age over 40, male sex, diabetes, smoking, alcohol, and manual labor. Diagnosis is clinical and treatment ranges from observation to needle procedures to surgery based on severity. Early diagnosis and management is key to optimizing hand function and preventing progression of this common hand deformity. While not life-threatening, loss of finger mobility can impair daily activities. Increased awareness and regular hand exams in high risk groups allows early detection and better outcomes. Further research is still needed to better understand the initiation and progression of Viking finger pathology.