A 42-year-old female presents to the emergency department with complaints of worsening finger pain. She reports the pain started 2 days ago with redness at the tip of the finger. Over the past 24 hours, her redness has spread and the finger has become more painful. On arrival, she is afebrile and hemodynamically stable. She has the below exam findings with tenderness along the volar aspect of the finger and pain with passive extension (Figure 1). What is your suspected diagnosis? What is your initial workup? What is your management and disposition?
 

Figure 1: Image obtained from WikEM

 

The patient has pyogenic flexor tenosynovitis. This is a bacterial infection of the flexor tendon sheath as a result of 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].

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 pathognomonic- fusiform digital swelling, finger held in slight flexion, pain with passive extension, and tenderness to palpation over the flexor tendon sheath (Figure 2) [2].

  • Pearl: Immunocompromised and diabetic patients may have a more indolent course or present more subtly. Keep a high index of suspicion for pyogenic flexor tenosynovitis in this population [3].

Figure 2: Image obtained from emDocs [4]

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 upon admission to further evaluate the tendon sheath [5]. Blood work, including CBC, BMP, and inflammatory markers (CRP and ESR) should also be obtained. These tests, when used in the right clinical context, have a high specificity (100%) but poor sensitivity (39-76%), so they may aid in supporting your diagnosis but should not be relied upon when trying to rule out the diagnosis [6].

  • Pearl: Ultrasound can be used to complement one’s clinical evaluation. For pyogenic flexor tenosynovitis, ultrasound has a reported 63% positive predictive value and 95% negative predictive value [7]. Detection of fluid in the tendon sheath can heighten one’s clinical suspicion, but a lack of fluid may be even more useful when trying to rule out the disease (Figure 3). 
Ultrasound of flexor tendon indicating fluid around the sheath

Figure 3: Case courtesy of Dr. Maulik S Patel, Radiopaedia.org, rID: 48661. Modified for annotations. Solid green arrow: tendon. Dashed green arrow: edema and fluid around the tendon.

Appropriate antibiotics, such as vancomycin PLUS piperacillin/tazobactam or ampicillin/sulbactam or ceftriaxone, and early surgical consultation with a hand specialist are critical. If the patient is diabetic, pseudomonas coverage should be added. 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 [5].

Check out ALiEM’s Paucis Verbis cards to brush up on other can’t miss orthopedic injuries, and SplintER Series for more potential tenosynovitis cases.

References

  1. Chapman T, Ilyas AM. Pyogenic Flexor Tenosynovitis: Evaluation and Treatment Strategies. J Hand Microsurg. 2019;11(3):121-126. PMID: 31814662
  2. Hyatt BT, Bagg MR. Flexor Tenosynovitis. Orthopedic Clinics of North America. 2017;48(2):217-227. PMID: 28336044
  3. Hermena S, Tiwari V. Pyogenic Flexor Tenosynovitis. In: StatPearls. StatPearls Publishing; 2022. Accessed March 30, 2022. PMID: 35015439
  4. emDOCs.net – Emergency Medicine EducationEM in 5: Flexor Tenosynovitis – emDOCs.net – Emergency Medicine Education. Accessed April 20, 2022. http://www.emdocs.net/em-in-5-flexor-tenosynovitis/
  5. Ray G, Sandean DP, Tall MA. Tenosynovitis. In: StatPearls. StatPearls Publishing; 2022. Accessed March 31, 2022. PMID: 31335044.
  6. Bishop GB, Born T, Kakar S, Jawa A. The diagnostic accuracy of inflammatory blood markers for purulent flexor tenosynovitis. J Hand Surg Am. 2013;38(11):2208-2211. PMID: 24206985
  7. Jardin E, Delord M, Aubry S, Loisel F, Obert L. Usefulness of ultrasound for the diagnosis of pyogenic flexor tenosynovitis: A prospective single-center study of 57 cases. Hand Surg Rehabil. 2018;37(2):95-98. PMID: 29396150
Justine Ko, MD

Justine Ko, MD

Sports Medicine Fellow
Departments of Emergency Medicine and Sports Medicine
MedStar Health/Georgetown University
Justine Ko, MD

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M. Terese Whipple, MD

M. Terese Whipple, MD

Assistant Professor
Department of Emergency Medicine
University of Iowa Hospitals and Clinics
M. Terese Whipple, MD

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Alexander J. Tomesch, MD

Alexander J. Tomesch, MD

Primary Care Sports Medicine Fellow
Department of Orthopedic and Sports Medicine
University of Arizona - Tucson
Alexander J. Tomesch, MD

@DocTomesch

Emergency Medicine/Sports Medicine physician, Husband, Father, Sports Enthusiast, Craft Beer Lover. Views are my own.
Alexander J. Tomesch, MD

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