What is the best course of action for an elderly patient with an isolated, minimally tender swelling of the middle phalanx of the ring finger, present for a few weeks?

Isolated Minimally Tender Swelling of Middle Phalanx in Elderly Patient

This presentation requires urgent imaging with plain radiographs followed by MRI to exclude bone sarcoma, which presents with persistent non-mechanical pain and swelling lasting weeks in elderly patients, and can be fatal if diagnosis is delayed. 1

Immediate Diagnostic Approach

Obtain three-view plain radiographs immediately to assess for bone destruction, periosteal reaction, cortical thinning, or soft tissue masses. 1, 2 The presence of persistent swelling in any bone lasting more than a few weeks should cause concern and lead to immediate investigation, as malignant bone tumors in adults over 40 years are most commonly metastases, myeloma, or primary bone sarcomas like chondrosarcoma. 1

If radiographs show any concerning features or are inconclusive, proceed immediately to MRI of the entire finger with adjacent joints. 1 MRI without and with IV contrast is the preferred modality for suspected bone lesions, soft tissue masses, or inflammatory processes, providing superior soft tissue detail. 2

Critical Differential Diagnoses to Exclude

Malignant Bone Tumors (Highest Priority)

• Chondrosarcoma is the most common primary bone sarcoma in adults aged 30-60 years, with an incidence of 0.2/100,000/year. 1 Persistent non-mechanical pain with swelling progressing over weeks is the classic presentation. 1
• Any destructive bone lesion after age 40 is most likely metastasis or myeloma until proven otherwise. 1
• All patients with suspected primary malignant bone tumor must be referred to a bone sarcoma reference center BEFORE biopsy. 1 Improper biopsy technique can contaminate tissue planes and compromise limb salvage surgery. 1

Glomus Tumor

• Presents with intense paroxysmal pain, point tenderness, and cold sensitivity in the fingertip, typically subungual. 3
• MRI shows characteristic lesion with possible bone erosion of the distal phalanx. 3
• Diagnosis confirmed with Love's pin test and Hildreth's test. 3

Upper Extremity Deep Vein Thrombosis

• Unilateral finger/hand swelling indicates an obstructive process requiring urgent duplex ultrasound to exclude UEDVT, which accounts for 10% of all DVTs and can cause pulmonary embolism. 2
• Remove all constricting jewelry immediately to prevent vascular compromise as swelling progresses. 2

Infection

• If septic arthritis or osteomyelitis is suspected based on fever, warmth, or systemic symptoms, obtain joint aspiration and consider drainage if abscess is identified. 2
• Send samples for microbiological culture in all cases. 1

Algorithmic Management Based on Imaging

If Radiographs Show Bone Destruction or Suspicious Lesion:

1. Do NOT perform biopsy at your facility. 1
2. Refer immediately to bone sarcoma reference center or orthopedic oncology. 1
3. Biopsy must be performed by the surgeon who will do definitive resection, using longitudinal incision with minimal tissue contamination. 1
4. Request form must include: tumor site, patient age, and suspected tumor type per 2013 WHO Classification. 1

If MRI Shows Soft Tissue Mass Without Bone Involvement:

• Consider glomus tumor if subungual location with characteristic MRI findings. 3
• Surgical excision with transungual approach provides best exposure and is curative. 3

If Duplex Ultrasound Confirms UEDVT:

• Initiate therapeutic anticoagulation immediately. 2
• Apply compression bandages or sleeves for persistent swelling. 2
• Investigate lower extremities if UEDVT confirmed without local cause. 2

If All Imaging is Negative:

• Reassess within 48-72 hours to evaluate response and ensure no progression. 2
• If swelling persists beyond 2 weeks without clear etiology, perform venography or advanced imaging to evaluate central veins. 2
• Schedule formal re-evaluation at 6 weeks if edema persists to detect delayed complications or underlying pathology maturation. 2

Critical Pitfalls to Avoid

Never dismiss persistent bone swelling in elderly patients as benign arthritis or trauma without imaging. 1 Bone sarcomas are frequently difficult to recognize as malignant by clinicians, radiologists, and pathologists, and delayed diagnosis significantly worsens prognosis. 1

Never perform biopsy at a non-specialized center. 1 Improper biopsy technique contaminates normal tissues and can convert a limb-salvage case into an amputation. 1

Never assume bilateral swelling and unilateral swelling have the same urgency. 2 Unilateral swelling indicates obstruction requiring urgent evaluation, while bilateral suggests systemic causes. 2

A recent injury does not rule out malignant tumor and must not prevent appropriate diagnostic procedures. 1