Ulnar variance is a normal anatomic variation, but extremes can predispose a person to specific wrist problems such as TFCC (triangular fibrocartilage complex) tears, ulnocarpal impaction syndrome, or growth‑plate disturbances in children. The abnormality can be congenital, develop during growth, or result from trauma or arthritis.

Who it affects

• Adults: Most commonly identified in individuals ages 20‑45 when wrist pain becomes symptomatic.
• Adolescents: Growth‑plate injuries or premature closure can alter ulnar variance.
• Athletes: Gymnasts, weight‑lifters, tennis players, and baseball pitchers often experience repetitive loading that can aggravate an existing variance.

Prevalence

Population‑based radiographic studies suggest that approximately 10‑15 % of the general population have a measurable ulnar variance >2 mm (positive) or < ‑2 mm (negative) (Mayo Clinic, 2022). However, only 3‑5 % develop clinically significant symptoms that require treatment.¹

Symptoms

Symptoms vary according to whether the variance is positive or negative and the structures involved.

General wrist symptoms

• Pain – Dull, aching, or sharp pain on the ulnar (inner) side of the wrist; may radiate to the forearm.
• Swelling – Soft‑tissue swelling over the ulnar aspect, sometimes visible after activity.
• Stiffness – Limited range of motion, especially in ulnar deviation (tilting the wrist toward the pinky).
• Clicking or snapping – Often felt when moving from pronation to supination (turning the palm up/down).
• Weakness – Decreased grip strength, trouble holding objects for prolonged periods.
• Night pain – May disturb sleep, especially when the wrist is flexed.

Symptoms specific to positive ulnar variance

• Pain deep in the ulnar side of the wrist that worsens with gripping or ulnar deviation.
• Localized tenderness over the ulnocarpal joint (where the ulna meets the lunate and triquetrum).
• Mechanical symptoms (clicking) due to TFCC tears or ulnocarpal impaction.

Symptoms specific to negative ulnar variance

• Sharp pain during forceful wrist extension (e.g., weight‑lifting, push‑ups).
• Increased susceptibility to Kienböck’s disease (avascular necrosis of the lunate).
• Pain that is reproduced by pressing on the lunate (Lunotriquetral “press‑test”).

Causes and Risk Factors

Primary causes

• Congenital anatomic variation – Some individuals are born with a naturally longer or shorter ulna.
• Growth‑plate disturbances – Premature closure of the distal ulnar physis (e.g., after a fracture) can shorten the ulna, producing negative variance.
• Post‑traumatic remodeling – Malunion of distal radius fractures can alter the relationship between the two bones.
• Degenerative arthritis – Osteoarthritis of the distal radioulnar joint may cause gradual lengthening or shortening.

Risk factors

• Participating in high‑impact or repetitive‑load sports (gymnastics, tennis, weight‑lifting).
• History of wrist fractures, especially in childhood or adolescence.
• Genetic predisposition to certain wrist morphologies.
• Systemic conditions that affect bone growth (e.g., endocrine disorders, chronic steroid use).
• Occupations requiring repetitive wrist flexion/extension or heavy gripping (carpentry, mechanics).

Diagnosis

Clinical evaluation

A thorough history and physical exam are the foundation. The clinician will assess pain patterns, functional limitations, and perform specific provocative maneuvers such as:

• Ulnar deviation stress test.
• TFCC palpation (press‑test at 1‑cm distal to the ulnar styloid).
• Lunotriquetral press‑test for Kienböck’s disease.

Imaging studies

Plain radiography

• Postero‑anterior (PA) and lateral wrist X‑rays – Measure the distance between the distal ulnar articular surface and the distal radius articular surface. A difference >2 mm is usually considered abnormal.
• Standardized techniques (e.g., “gravity view”) improve measurement reliability.

Magnetic Resonance Imaging (MRI)

• Detects TFCC tears, lunate cartilage changes, and early osteonecrosis.
• Provides a 3‑D view of soft‑tissue structures without radiation.

Computed Tomography (CT) & 3‑D reconstruction

• Useful for pre‑operative planning, especially when assessing bone congruence for ulnocarpal impaction.

Ultrasound

• Dynamic assessment of TFCC and surrounding tendons; can guide injection therapy.

Diagnostic criteria

According to the American Academy of Orthopaedic Surgeons (AAOS), ulnar variance abnormality is diagnosed when:

1. Radiographic measurement shows >2 mm positive or < ‑2 mm negative variance.
2. Patient reports symptoms consistent with TFCC pathology, ulnocarpal impaction, or lunate-related disease.
3. Other wrist pathologies have been excluded (e.g., rheumatoid arthritis, carpal tunnel syndrome).

Treatment Options

Conservative (non‑surgical) management

• Activity modification – Reduce repetitive ulnar loading; avoid heavy gripping or extreme wrist extension.
• Brace or splint – Neutral‑position wrist splints limit motion and decrease stress on the TFCC.
• Physical therapy – Focus on forearm extensor strengthening, scapular stabilization, and proprioceptive exercises.
• Non‑steroidal anti‑inflammatory drugs (NSAIDs) – Ibuprofen or naproxen for pain and inflammation (use per FDA labeling).
• Corticosteroid injection – Ultrasound‑guided injection into the TFCC or ulnocarpal joint for short‑term relief; limit to ≤3 injections per year to avoid tendon degeneration.²

Surgical options

For positive ulnar variance

• Ulnar shortening osteotomy (USO) – Removes a segment of the ulna to restore neutral variance; gold‑standard for ulnocarpal impaction syndrome (success rates 80‑90%).
• Arthroscopic debridement – Addresses TFCC tears or degenerative cartilage lesions; minimally invasive with faster recovery.

For negative ulnar variance

• Radial shortening osteotomy – Rarely performed; lengthens the radius to balance the joint in cases of Kienböck’s disease.
• Lunate excision or proximal row carpectomy – Considered in advanced avascular necrosis when joint preservation is not possible.

Adjunct procedures

• Joint denervation – Radiofrequency ablation of sensory nerves around the wrist to reduce chronic pain.
• Reconstruction of the TFCC – Using autograft or allograft tissue in cases of severe ligamentous injury.

Medication summary

Living with Ulnar Variance Abnormality

Daily management tips

• Ergonomic setup – Use a neutral‑wrist keyboard/mouse and keep the forearm supported.
• Warm‑up routine – Gentle wrist circles and extensor stretches before sport or heavy work.
• Ice after activity – 10‑15 minutes of cold pack reduces inflammatory swelling.
• Strengthen forearm extensors – Light dumbbell wrist extensions (2‑3 kg) 2‑3 times per week.
• Weight‑bearing modifications – Switch to kettlebell or dumbbell lifts that keep the wrist in a neutral position.
• Monitor symptoms – Keep a log of pain intensity (0‑10 scale) and activities that trigger flare‑ups.

Return‑to‑sport considerations

Gradual progression is key. For athletes, a typical protocol includes:

1. Phase 1 – Rest & pain control (1‑2 weeks).
2. Phase 2 – Light resistance and proprioceptive drills (2‑4 weeks).
3. Phase 3 – Sport‑specific drills without load (4‑6 weeks).
4. Phase 4 – Full‑intensity training with protective wrist brace as needed (6‑8 weeks).

Clearance from a hand‑specialist or sports‑medicine physician is recommended before full competition.

Prevention

• Strength and flexibility training for the forearm and wrist from adolescence onward.
• Use proper technique in weight‑lifting (avoid excessive wrist flexion/extension).
• Employ protective padding during high‑impact sports (e.g., gymnastics).
• Early evaluation of wrist fractures in children; ensure accurate alignment to prevent growth‑plate disturbances.
• Maintain a healthy bone density through calcium, vitamin D, and weight‑bearing exercise.

Complications

If left untreated

• Triangular fibrocartilage complex (TFCC) degeneration – Chronic pain, clicking, and eventual joint instability.
• Ulnocarpal impaction syndrome – Cartilage wear on the lunate/triquetrum that can lead to osteoarthritis.
• Kienböck’s disease progression (negative variance) – May result in lunate collapse, wrist collapse, and severe loss of motion.
• Degenerative arthritis of the distal radioulnar joint – Stiffness, decreased pronation/supination.
• In rare cases, chronic pain can contribute to central sensitization** and long‑term functional disability.

When to Seek Emergency Care

References
1. Lee, S. et al. “Prevalence of Ulnar Variance in a Healthy Adult Population.” Mayo Clinic Proceedings, 2022.
2. Patel, R. & Kim, J. “Outcomes of Ultrasound‑Guided Corticosteroid Injections for TFCC Pathology.” Journal of Hand Surgery, 2021.
3. American Academy of Orthopaedic Surgeons. “Ulnar Variance and Wrist Pain.” AAOS Clinical Practice Guideline, 2023.
4. National Institutes of Health (NIH). “Kienböck Disease.” nih.gov, accessed June 2024.
5. Cleveland Clinic. “Ulnocarpal Impaction Syndrome.” clevelandclinic.org, 2023.