What is the treatment for short ulna syndrome?

Treatment for Short Ulna Syndrome

For patients with short ulna syndrome (ulnar negative variance), treatment should begin with conservative management including activity modification, splinting, and analgesics, reserving surgical intervention (primarily radial shortening osteotomy) for cases with progressive symptoms or development of associated pathology like Kienböck's disease. 1, 2

Initial Diagnostic Evaluation

When patients present with wrist pain and radiographs demonstrate ulnar negative variance, advanced imaging is essential to identify associated pathology:

• MRI without IV contrast is the preferred next imaging study for persistent symptoms with normal or nonspecific radiographs, as it can detect soft tissue abnormalities, bone marrow edema, and early Kienböck's disease that occur more frequently in symptomatic patients 1, 2
• CT without IV contrast serves as an alternative imaging modality when MRI is contraindicated 2
• Ultrasound can assess ulnar collateral ligament integrity with high diagnostic accuracy (sensitivity 77-79%, specificity 94-98%) 1

Conservative Management (First-Line Treatment)

For asymptomatic or mildly symptomatic cases, observation alone is sufficient 1, 2. When symptoms are present, a structured conservative approach should include:

Activity Modification

• Avoid activities that place excessive load on the wrist, particularly repetitive gripping or impact activities 1, 2

Immobilization and Support

• Rigid immobilization is preferred over removable splints for better symptom control, especially when there is associated thumb base or wrist pain 1, 2
• Splints or orthoses provide effective symptom relief in many cases 1, 2

Pharmacologic Management

• Paracetamol (up to 4g/day) is the first-choice oral analgesic due to its efficacy and favorable safety profile 1, 2
• Topical NSAIDs are effective for localized pain with fewer systemic side effects than oral formulations 1, 2
• Oral NSAIDs at the lowest effective dose for the shortest duration may be considered when paracetamol provides inadequate relief 1, 2

Physical Therapy

• Range of motion and strengthening exercises help maintain wrist function 1, 2
• Local heat application before exercise may provide additional symptomatic benefit 1, 2

Surgical Intervention

Surgical options are reserved for cases where conservative management fails or when there is progression to conditions like Kienböck's disease 1, 2. The primary surgical procedures include:

Radial Shortening Osteotomy

• This is the procedure of choice to address ulnar negative variance surgically, as it equalizes the length discrepancy by shortening the radius rather than lengthening the ulna 1, 2
• This approach avoids complications associated with ulnar lengthening procedures 3

Joint-Leveling Procedures

• Alternative surgical techniques may be appropriate in select cases depending on the specific anatomic abnormalities present 1, 2

Monitoring and Follow-Up

Regular radiographic follow-up is essential to monitor for progression to conditions associated with ulnar negative variance, particularly Kienböck's disease (avascular necrosis of the lunate) 1, 2. Key monitoring principles include:

• Treatment decisions should be based on symptoms, functional limitations, and evidence of associated pathology rather than the radiographic finding alone 1, 2
• The presence of ulnar negative variance on radiographs does not mandate treatment in asymptomatic individuals 1, 2
• Periodic assessment is particularly important in patients with persistent symptoms despite conservative management 2

Important Clinical Considerations

A critical pitfall is treating the radiographic finding rather than the clinical presentation. Many individuals have ulnar negative variance without symptoms and require no intervention 1, 2. Conversely, symptomatic patients may have associated pathology (TFCC tears, lunotriquetral ligament injuries, early Kienböck's disease) that requires specific treatment beyond addressing the length discrepancy alone 3.

When structural abnormalities are identified and appropriately addressed through either conservative or surgical means, treatment can be expected to be effective in the majority of cases 3.