What is your diagnosis?

The patient is diagnosed with pyogenic flexor tenosynovitis. This can result from hematogenous spread or local inoculation. Most commonly it is caused by trauma or injury to the hand [1].

• Pearl: Common pathogens include staphylococcus and streptococcus species. Be sure to cover for these when starting antibiotics [1]!

How does this injury present? What are some key exam findings?

The patient often will present within a few days of injury [2].They will have significant pain and swelling of the affected finger. Kanavel’s cardinal signs can be helpful with diagnosis- fusiform digital swelling, finger held in slight flexion, pain with passive extension, and tenderness to palpation over the flexor tendon sheath (Image 2) [2].

• Pearl: Immunocompromised and diabetic patients may have a more indolent course or present more subtly. Keep a high index of suspicion [3]. 

Image 2: Image obtained from emDocs

How is it diagnosed?

When these patients present, an x-ray of the finger/hand should be obtained to evaluate for foreign bodies. While the diagnosis is largely clinical, MRI can be ordered to evaluate the tendon sheath [4]. Blood work, including CBC, BMP, and inflammatory markers should also be obtained. 

• Pearl: Bedside ultrasonography can help detect fluid in the tendon sheath and heighten one’s clinical suspicion. Image 3 shows short axis images along the affected finger and demonstrates synovial thickening and an effusion surrounding the tendon.

Image 3: Case courtesy of Dr Maulik S Patel, Radiopaedia.org, rID: 48661

What is your management in the ED? What is your disposition?

Early antibiotics and surgical consultation is key! These patients will generally be admitted for close monitoring and surgical management. Delayed treatment can have poor long term outcomes for patients. In most cases, surgical drainage is required in addition to intravenous antibiotics [4].