What is the cause of right elbow pain and weakness in a patient with a history of car accident, medial epicondylitis, and symptoms including pain with pronation and gripping, weakness when holding objects, and no current numbness?

Differential Diagnosis for Right Elbow Pain and Weakness

This patient most likely has medial epicondylitis (golfer's elbow) with coexistent ulnar neuropathy at the cubital tunnel, given the history of car accident, prior diagnosis of golfer's elbow, pain with pronation/gripping, and the specific weakness in the 4th and 5th fingers of the left hand (though the question states right elbow, the hand symptoms suggest ulnar nerve involvement). 1

Primary Diagnostic Considerations

Medial Epicondylitis with Ulnar Nerve Involvement

• Coexistent ulnar neuritis occurs in approximately 50% of medial epicondylitis cases, making this a critical diagnostic consideration 2, 3
• The weakness specifically affecting the 4th and 5th fingers with compensatory thumb use is highly suggestive of ulnar nerve dysfunction rather than isolated tendinopathy 1
• Pain with pronation and gripping while supination remains unaffected is consistent with flexor-pronator origin pathology at the medial epicondyle 1

Cervical Radiculopathy (C6/C7)

• Over 50% of patients with C6 and C7 radiculopathy present with medial epicondylitis, as nerve root compression causes weakness and imbalance in elbow flexor/extensor muscles 4
• The history of car accident raises suspicion for cervical spine injury that could manifest as both neck and elbow symptoms 4
• This diagnosis must be actively excluded, as treating only the elbow will fail if cervical pathology is the underlying cause 4

Snapping Elbow Syndrome

• This uncommon condition can cause posterior-medial elbow pain and is frequently misdiagnosed as medial epicondylitis 3
• Involves ulnar nerve instability or abnormal triceps anatomy causing recurrent nerve subluxation 3
• Should be considered given the history of trauma (car accident) and persistent symptoms despite prior physiotherapy 3

Critical Workup Algorithm

Step 1: Initial Imaging

• Obtain plain radiographs of the elbow (AP and lateral views) immediately to rule out osseous pathology, intra-articular bodies, heterotopic ossification, osteochondral lesions, and occult fractures from the prior car accident 1, 5

Step 2: Neurologic Assessment

• Perform EMG and nerve conduction studies given the specific 4th and 5th finger weakness, as this strongly suggests ulnar neuropathy requiring electrodiagnostic confirmation 1
• Examine for ulnar nerve subluxation with elbow flexion/extension, which indicates cubital tunnel syndrome 1
• Test for Tinel's sign at the cubital tunnel and assess for paresthesias in ulnar nerve distribution 1

Step 3: Cervical Spine Evaluation

• Examine the cervical spine for C6/C7 radiculopathy given the car accident history and the high prevalence of cervical pathology presenting as medial epicondylitis 4
• Look for neck pain, limited cervical range of motion, and positive Spurling's test 4

Step 4: Advanced Imaging (if radiographs normal)

• Order MRI of the elbow without contrast if plain films are normal but clinical suspicion remains high for tendon tear, nerve entrapment, or soft tissue pathology 1, 5
• T2-weighted MR neurography is the reference standard for imaging ulnar nerve entrapment, showing high signal intensity and nerve enlargement 1

Key Clinical Distinctions

Physical Examination Findings to Differentiate Diagnoses

Medial Epicondylitis:

• Pain directly over the medial epicondyle with resisted wrist flexion and pronation 1
• Pain with gripping activities 1

Ulnar Collateral Ligament (UCL) Injury:

• Pain with valgus stress testing (distinct from epicondyle tenderness) 1
• Medial joint line tenderness rather than epicondyle tenderness 1
• Positive moving valgus stress test 1

Cubital Tunnel Syndrome:

• Ulnar nerve subluxation with elbow flexion/extension 1
• Paresthesias in 4th and 5th fingers 1
• Weakness of intrinsic hand muscles 1

Intra-articular Pathology:

• Mechanical symptoms (locking, clicking, catching) 1
• Pain with passive range of motion (differentiates from tendinopathy) 1
• Limited range of motion and effusion 1

Red Flags Requiring Urgent Investigation

• Night pain or pain at rest suggests inflammatory or neoplastic process rather than mechanical tendinopathy 1, 5
• Mechanical symptoms (locking, catching) indicate intra-articular pathology requiring imaging 1
• Progressive neurologic symptoms warrant urgent electrodiagnostic studies and possible surgical consultation 1

Common Diagnostic Pitfalls

Critical Errors to Avoid

• Failing to obtain initial radiographs is a major pitfall, as the car accident history necessitates ruling out post-traumatic osseous changes 1, 5
• Overlooking coexistent ulnar neuritis leads to poor outcomes, as isolated treatment of medial epicondylitis fails when nerve pathology is present 2
• Missing cervical radiculopathy results in treatment failure, as the elbow symptoms are secondary to nerve root compression 4
• Overreliance on corticosteroid injections without addressing underlying biomechanical issues or neurologic pathology 1

Specific to This Case

• The discrepancy between right elbow pain and left hand weakness (4th and 5th fingers) needs clarification—if truly right elbow with left hand symptoms, this suggests a central or cervical cause rather than peripheral pathology
• The worsening after a specific movement one month ago may represent acute-on-chronic injury requiring imaging to assess for tendon tear 1
• Previous physiotherapy that improved then regressed suggests either incomplete treatment, wrong diagnosis, or coexistent pathology not addressed 2

Most Likely Diagnosis

Given the constellation of findings—prior golfer's elbow diagnosis, specific 4th and 5th finger weakness, pain with pronation/gripping, history of trauma, and regression after initial improvement—this patient most likely has medial epicondylitis with coexistent ulnar neuropathy, potentially complicated by cervical radiculopathy from the car accident 2, 4. The prognosis is significantly worse when ulnar neuritis coexists, with only 12.5% achieving symptom resolution compared to 69% with isolated medial epicondylitis 2.