Refractory Ankle Pain: A Case of Septic Arthritis
Vignette
A. Bone biopsy
B. MRI with contrast
C. Arthrocentesis
D. Medical history and physical exam
Introduction
Septic arthritis is a painful infection involving the joints of the body that may stem from a local penetrating injury (bite, drug injection, prior joint replacement, trauma, etc.) or another infection in the body, such as a urinary tract infection or bacteremia, that spreads through the bloodstream to seed a joint. While uncommon (2-10 cases per 100,000 per year), the incidence of septic arthritis appears to be increasing, possibly due to an aging population, increased antibiotic resistance, and the use of immunosuppressive agents.[1]Kalagate R, Rivera A, Pritchard CH, Brent LH. Thu0369 septic arthritis: Changing trends in epidemiology over two decades. Annals of the Rheumatic Diseases. … Continue reading Septic arthritis is a must rule out diagnosis, especially when accompanied by cardinal signs of inflammation, including redness (rubor), swelling (tumour), heat (calor), pain (dolor) and loss of function (functio laesa). The ankle (8.6%) is the fourth most involved joint in septic arthritis, following the knee (45.7%), hip (31.4%), and shoulder (11.4%).[2]Mue D, Salihu M, Awonusi F, Yongu W, Kortor J, Elachi I. The epidemiology and outcome of acute septic arthritis: A hospital based study. Journal of the West African College of Surgeons. … Continue reading If left untreated or treatment is delayed, septic arthritis can lead to joint degeneration and permanent damage.
Differential Diagnosis
- Musculoskeletal: fracture, ligament sprain, tendon strain/tendinitis, muscular strain, arthritis
- Integumentary: cellulitis
- Lymphatic: lymphedema
- Hematologic: hematoma
- Infectious: septic arthritis, osteomyelitis
- Autoimmune: rheumatoid arthritis
- Inflammatory: gout, pseudogout
Diagnosis
Lab Marker[5]Luo TD, Jarvis DL, Yancey HB, Zuskov A, Tipton SC, Langfitt MK. Synovial cell count poorly predicts septic arthritis in the presence of crystalline arthropathy. Journal of Bone and Joint Infection. … Continue reading | Lab Value | PPV | NPV | Sensitivity | Specificity |
---|---|---|---|---|---|
Joint/Synovial WBC[6]Luo TD, Jarvis DL, Yancey HB, Zuskov A, Tipton SC, Langfitt MK. Synovial cell count poorly predicts septic arthritis in the presence of crystalline arthropathy. Journal of Bone and Joint Infection. … Continue reading | >50k or <50k | 32.6% | 92.9% | 61.2% | 79.9% |
Gram Stain[7]Luo TD, Jarvis DL, Yancey HB, Zuskov A, Tipton SC, Langfitt MK. Synovial cell count poorly predicts septic arthritis in the presence of crystalline arthropathy. Journal of Bone and Joint Infection. … Continue reading | +/- | 82.4% | 89.7% | 28.6% | 99% |
Synovial Lactate[8]Shu E, Farshidpour L, Young M, Darracq M, Ives Tallman C. Utility of point-of-care synovial lactate to identify septic arthritis in the emergency department. The American Journal of Emergency … Continue reading | >5 mmol/L >10 mmol/L | - | - | 55% 26% | 76% 97% |
CRP[9]Hariharan P, Kabrhel C. Sensitivity of erythrocyte sedimentation rate and C-reactive protein for the exclusion of septic arthritis in emergency department patients. The Journal of Emergency Medicine. … Continue reading | >20 mg/L | - | - | 92% | - |
ESR[10]Hariharan P, Kabrhel C. Sensitivity of erythrocyte sedimentation rate and C-reactive protein for the exclusion of septic arthritis in emergency department patients. The Journal of Emergency Medicine. … Continue reading | >10 mm/h >15 mm/h | - | - | 98% 94% | - |
Imaging
Risk Factors
Management
Ankle Arthrocentesis
- Palpate the anterior border of the medial malleolus and tibialis anterior tendon. The needle should be introduced between these two structures. To make the tibialis anterior tendon more prominent, dorsiflex the ankle and extend the toes.
- Mark your injection site before cleaning the area. Apply several layers of iodine, followed by alcohol to prepare the space. Use of sterile gloves is recommended.
- Use a 25-to-27-gauge needle to create a wheal of local anesthetic. Proceed to keep injecting down to the area of the joint capsule. Coolant may be used to alleviate the pain from the initial introduction of the needle.
- Introduce a 20-to-22-gauge needle in a perpendicular fashion to the shaft of the patient’s tibia. You may meet resistance with bone. In this case, withdraw slightly and redirect at a different angle. As you advance your needle past the half-inch mark, begin aspirating. Once fluid is aspirated into the syringe, the correct spot has been identified. If the fluid stops or slows down, consider advancing the needle more or retracting the needle and going at a slightly altered angle.
Case Conclusion
– Read More @ Wiki Sports Medicine: https://wikism.org/Septic_Arthritis
Vignette Answer
References[+]
↑1 | Kalagate R, Rivera A, Pritchard CH, Brent LH. Thu0369 septic arthritis: Changing trends in epidemiology over two decades. Annals of the Rheumatic Diseases. https://ard.bmj.com/content/71/Suppl_3/280.2. Published June 1, 2013. |
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↑2 | Mue D, Salihu M, Awonusi F, Yongu W, Kortor J, Elachi I. The epidemiology and outcome of acute septic arthritis: A hospital based study. Journal of the West African College of Surgeons. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4228814/. |
↑3 | Li SF, Cassidy C, Chang C, Gharib S, Torres J. Diagnostic utility of laboratory tests in septic arthritis. Emergency medicine journal : EMJ. https://www.ncbi.nlm.nih.gov/pmc/article/PMC2658211/. |
↑4, ↑8 | Shu E, Farshidpour L, Young M, Darracq M, Ives Tallman C. Utility of point-of-care synovial lactate to identify septic arthritis in the emergency department. The American Journal of Emergency Medicine. 2019;37(3):502-505. doi:10.1016/j.ajem.2018.12.030 |
↑5, ↑6, ↑7 | Luo TD, Jarvis DL, Yancey HB, Zuskov A, Tipton SC, Langfitt MK. Synovial cell count poorly predicts septic arthritis in the presence of crystalline arthropathy. Journal of Bone and Joint Infection. 2020;5(3):118-124. doi:10.7150/jbji.44815 |
↑9, ↑10 | Hariharan P, Kabrhel C. Sensitivity of erythrocyte sedimentation rate and C-reactive protein for the exclusion of septic arthritis in emergency department patients. The Journal of Emergency Medicine. 2011;40(4):428-431. doi:10.1016/j.jemermed.2010.05.029 |
↑11 | Kaandorp CJ, Schaardenburg DV, Krijnen P, Habbema JD, Van De Laar MA. Risk factors for septic arthritis in patients with joint disease. Arthritis & Rheumatism. 1995;38(12):1819-1825. doi:10.1002/art.1780381215 |
↑12 | Frydrych LM, Fattahi F, He K, Ward PA, Delano MJ. Diabetes and sepsis: Risk, recurrence, and Ruination. Frontiers in endocrinology. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5670360/. |
↑13 | Long B, Koyfman A, Gottlieb M. Evaluation and management of septic arthritis and its mimics in the emergency department. Western Journal of Emergency Medicine. 2019;20(2):331-341. doi:10.5811/westjem.2018.10.40974 |
↑14 | Image courtesy of merckmanuals.com, “How To Do Ankle Arthrocentesis” |