Orthopaedic MD

A child with isolated Mycobacterium tuberculosis monoarthritis, with features initially suggesting oligoarthritis subtype of juvenile idiopathic arthritis, is presented. This patient illustrates the need to consider the possibility of tuberculosis as the cause of oligoarthritis in high-risk pediatric populations even in the absence of a tuberculosis contact history and without evidence of overt pulmonary disease.
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Derek Rajakumar email and Alan M Rosenberg email Pediatric Rheumatology 2008, 6:15

McMaster Grand Rounds Presentation

Historically, synovial fluids have been classified as noninflammatory (WBC count 50-1000), inflammatory (WBC count 1000-75,000), septic (WBC count>100,000), or hemorrhagic. However, septic synovial fluid can have cell counts as low as a few thousand early in the infectious process; thus, differentiation of inflammatory and septic joints is not truly possible based on cell counts alone. When a patient presents with an acute or chronic monoarthritis, infectious arthritis should be considered. In one study of 77 patients with septic arthritis, the peripheral blood leukocyte count was within the reference range in 55% of the patients, and, in 13% of the cases, the erythrocyte sedimentation rate (ESR) was less than 20 mm/h. The diagnostic value of the synovial fluid leukocyte count in an individual case is poor. Counts below 25,000/mm3 are observed commonly in infectious arthritis. Thus, the key diagnostic test when septic arthritis is suggested is arthrocentesis with analysis and culture of synovial fluid. Patients may present with polyarticular involvement, so the presence of multiple inflamed joints does not rule out infectious arthritis. Polyarticular involvement is the rule in certain types of arthritis, such as gonococcal arthritis and rheumatoid arthritis (RA). The important message for the physician is to be aggressive in looking for infectious arthritis. If septic arthritis is suggested, aspirate. In skilled hands, the discomfort and morbidity of joint aspiration are minimal. The speed of diagnosis is the most important determinant of the outcome.
Synonyms and related keywords: synovial fluid, acute monoarthritis, chronic monoarthritis, polyarticular arthritis, infectious arthritis, gonococcal arthritis, rheumatoid arthritis, RA, infection
Author: Nadera Sweiss, MD 2003

Infective arthritis may represent a direct invasion of joint space by various microorganisms, including bacteria, viruses, mycobacteria, and fungi. Reactive arthritis, a sterile inflammatory process, may be the consequence of an infectious process located elsewhere in the body. Although any infectious agent may cause arthritis, bacterial pathogens are the most significant because of their rapidly destructive nature. For this reason, the current discussion concentrates on bacterial septic arthritides. Failure to recognize and to appropriately treat septic arthritis results in significant rates of morbidity and may even lead to death.
Because of the increasing use of prosthetic joints, infection associated with these devices may be the most common and challenging type of septic arthritis encountered by most clinicians.
Synonyms and related keywords: reactive arthritis, inflammatory arthritis, bacterial septic arthritides, bacterial septic arthritis, suppurative arthritis, Neisseria gonorrhoeae, N gonorrhoeae, Staphylococcus aureus, S aureus, Streptococcus viridans, S viridans, Streptococcus pneumoniae, S pneumoniae, group B streptococci, crystalline arthritis, Lyme disease, Lyme arthritis, prosthetic joint infections, PJI, rheumatoid arthritis
John L Brusch, MD 2006

Septic arthritis is inflammation of a synovial membrane with purulent effusion into the joint capsule, usually due to bacterial infection. This disease entity also is referred to in the literature as bacterial, suppurative, purulent, or infectious arthritis. Septic arthritis is a rather rare but important disease that typically affects monoarticular joints. The age range of those affected is broad, from the neonatal period to advanced age. Treatment consists of a combined medical and surgical approach. Septic arthritis usually is divided into gonococcal and nongonococcal arthritis, as clinical and treatment regimens differ. In adults, septic arthritis most commonly affects the knee; in children, infection into the hip joint predominates. Despite advances in diagnostic studies, powerful antibiotics, and early drainage, significant joint destruction commonly occurs.
Synonyms and related keywords: bacterial arthritis, suppurative arthritis, purulent arthritis, infectious arthritis
Munoz & Raycraft 2006

Bombay Hospital Journal Volume 44 No.1, January 2002
JD Jagiasi, S Aiyer, JV Patankar, AB Goregaonkar
Septic Arthritis in newborn Babies is a well-known entity. If not treated at the right time can cause disasters. We present here a series of eight new born babies (six hips, one knee and one shoulder) between age group of 1 week to 3 weeks, these babies didn’t show all the classic signs2 of septic arthritis like fever, leucocytosis, ramification of bone seen on the x-ray. The only finding suggestive of septic arthritis was swelling over the joint and reduced movements of the affected extremity (pseudoparesis), and effusion seen of the involved joint on Ultrasonography.

Septic arthritis in infancy and childhood is a true clinical emergency. Delays in the diagnosis and treatment of septic arthritis can result in disastrous complications, including complete destruction of the articular cartilage and the underlying epiphysis, loss of the adjacent growth plate, and dislocation of the joint. With prompt treatment, the condition may be cured and sequelae avoided; the clinician must be alert to a diagnosis that can be subtle, particularly in the young child or infant. Pain with passive motion is the most consistent finding in septic arthritis, and the diagnosis must be considered in any joint with this presentation. This article focuses on the most common presentations of septic arthritis as it occurs in infancy and childhood. Important variations from these common presentations are seen in septic arthritis in the neonate and with gonococcal arthritis.
Synonyms and related keywords: joint infections, septic joint, suppurative arthritis, bacterial arthritis, acute septic arthritis, pyogenic arthritis, gonococcal arthritis, Haemophilus influenzae type b, H influenzae type b, Staphylococcus aureus, S aureus
Author: Edwards P Schwentker, MD

- septic arthritis of the hip is a surgical emergency;
- it is essential that dx be made ASAP to prevent joint damage;
- if any pus is obtained from arthrotomy, then immediate arthrotomy is indicated, regardless of the Graim Stain results;
- w/ younger child, more pressing is need because of higher risk of permanent disability;
Wheeless' Textbook of Orthopaedics

See notes on:
- Bursae of the Knee:
- Septic Arthritis:
- Diff Dx:
- referred pain from the hip
- osteochondritis dissecans
- traumatic internal derangement
- distal femoral or proximal tibial osteomyelitis
- septic bursitis:
- lyme disease
Wheeless' Textbook of Orthopaedics