Management of Slight Positive Ulnar Variance After Fall
Initial management should focus on conservative treatment with NSAIDs, activity modification, and wrist splinting, as positive ulnar variance after trauma may represent acute soft tissue injury rather than chronic ulnar impaction syndrome requiring surgical intervention. 1
Initial Diagnostic Approach
Standard radiographs are the essential first imaging study and should include posteroanterior, lateral, and oblique views performed in neutral position and rotation to accurately measure ulnar variance. 1
- The lateral view is critical for demonstrating malalignments and soft-tissue swelling that may indicate acute injury. 1
- Radiographs alone may establish the diagnosis in cases of arthritis, complications of injury, impaction syndromes, or static wrist instability. 1
Clinical Context Matters
The key distinction is whether this represents:
Acute traumatic injury with transient positive variance (most likely after a fall):
- Soft tissue swelling and inflammation can temporarily increase ulnar variance
- Pain may be from triangular fibrocartilage complex (TFCC) injury, ligament sprain, or bone contusion
- Conservative management is appropriate initially
Chronic ulnar impaction syndrome (less likely if truly new after fall):
- Degenerative condition from excessive ulnocarpal joint loading 2
- Associated with TFCC degeneration, cartilage wear of lunate and triquetrum 2, 3
- Typically requires pre-existing positive ulnar variance (congenital or acquired) 2
Conservative Treatment Protocol
Initial 6-8 weeks of conservative management should include:
- NSAIDs for pain and inflammation control 2
- Wrist splinting to reduce ulnocarpal loading
- Activity modification avoiding forceful gripping and ulnar deviation 2
- Physical therapy for range of motion once acute pain subsides
When to Advance Imaging
If pain persists beyond 6-8 weeks of conservative treatment with normal or nonspecific radiographs, MRI without IV contrast is the next appropriate study. 1
MRI is highly accurate for:
- TFCC tears (both traumatic and degenerative lesions) using high-resolution sequences 1
- Ligament injuries (scapholunate, lunotriquetral) 1
- Occult fractures and bone marrow edema 1
- Extra-articular pathology (tendon disorders, ganglion cysts) 1
MR arthrography may be considered if standard MRI is equivocal, as it has higher sensitivity for TFCC peripheral tears and ligament injuries. 1
Surgical Considerations (Only After Failed Conservative Treatment)
Ulnar shortening osteotomy is the definitive surgical treatment for symptomatic ulnar impaction syndrome with positive ulnar variance, but this is indicated only when:
- Conservative treatment fails after adequate trial (minimum 3-6 months) 4, 2, 5
- Confirmed TFCC pathology and/or ulnocarpal degenerative changes on advanced imaging 4, 5
- Persistent ulnar-sided pain, restricted forearm rotation, and grip weakness 5
Surgical outcomes show:
- 92% (23/25 patients) achieved complete relief or occasional mild pain after ulnar shortening for TFCC tears with positive ulnar variance 5
- Average shortening of 3mm with osteotomy healing at 7 weeks 5
- Complications include reflex sympathetic dystrophy and fracture through osteotomy site with early plate removal 5
Critical Pitfalls to Avoid
Do not rush to surgical intervention for acute post-traumatic positive ulnar variance, as this may represent temporary soft tissue changes rather than chronic impaction syndrome requiring osteotomy. 2, 3
Recognize that dynamic ulnar variance exists: pronated-grip radiographs may reveal increased positive variance not visible on standard views, which can be clinically relevant for surgical planning if conservative treatment fails. 6
Arthroscopy should be considered before or during ulnar shortening to directly visualize TFCC tears, assess degenerative changes of lunate and triquetrum, and potentially debride traumatic flap tears. 5