Abstract
Glenohumeral joint sepsis is an unusual indication for shoulder arthroscopy. Arthroscopy has greatly facilitated the management of this difficult condition. Treatment goals include acquiring fluid cultures and tissue biopsies to identify the infecting organism or organisms; determining the extent of tissue involvement; and joint irrigation and débridement in a manner that minimizes morbidity and allows early functional recovery. Often, serial arthroscopic débridements are indicated.
Keywords
sepsis, infection, osteomyelitis, débridement
Glenohumeral joint sepsis is an unusual indication for shoulder arthroscopy. Arthroscopy has greatly facilitated the management of this difficult condition. Treatment goals include acquiring fluid cultures and tissue biopsies to identify the infecting organism or organisms and determining the extent of tissue involvement, followed by joint irrigation and débridement in a manner that minimizes morbidity and allows early functional recovery. Serial needle aspirations cannot remove all joint debris or reach all loculations and infected clots. Arthrotomy enables thorough irrigation and débridement, but with increased soft tissue injury compared with arthroscopic treatment.
Literature Review
Most series on sepsis in various joints report the incidence of shoulder involvement as 3% to 12%. The most common organisms isolated are Staphylococcus aureus (61%) and Staphylococcus epidermidis (17%), but polymicrobial infections are frequent (67%). In his series, Gelberman noted that all patients had significant underlying medical conditions, such as alcoholism, liver disease, malignancy, heroin addiction, or renal failure. Patients with acquired immunodeficiency syndrome and patients who have undergone shoulder replacement may also present with septic shoulders. The rise of methicillin-resistant S. aureus and Propionibacterium acnes is of concern. The latter is very difficult to detect with laboratory analysis.
Diagnosis
All studies on shoulder pyarthrosis have noted a delay in establishing a diagnosis because the clinical findings may be subtle. Patients are often afebrile and may complain of nonspecific shoulder discomfort. The white blood cell count may be normal, especially if the patient is immunocompromised. Peripheral labs, such as the erythrocyte sedimentation rate and the C-reactive protein, may be elevated, but are still not specific. The literature on this subject confirms that glenohumeral joint infections are very difficult to diagnose, and any or all tests may be negative despite an ongoing infection. Native joint infections are rare, but a new subset of patients has been added to the pool of potential joint infections, classified as postoperative infections. With the increase in shoulder surgery, and arthroplasty in particular, infections are more common. In patients with no arthroplasty in place, diagnostic work-up can include labs, as mentioned, and radiographs or magnetic resonance imaging with guided aspiration for cell count, Gram stain, and culture if indicated ( Figs. 9.1–9.3 ). If an arthroplasty is in place, labs and a computed tomography scan with guided aspiration for cell count, Gram stain, and culture can be helpful. All cultures should be held for a minimum of 4 weeks to ensure that Propionibacterum acnes is not missed.
If the diagnosis of glenohumeral infection is still not clear after the diagnostic evaluation, we generally have a low threshold to proceed with diagnostic arthroscopy. Certainly, antibiotics are held prior to surgery, and none are given intraoperatively until all specimens have been obtained.
Operative Technique
A routine posterior portal is established with a metal trocar. We do not insufflate the joint. Fluid is collected through the cannula when the trocar is withdrawn. After the arthroscope is inserted posteriorly, an anterior-inferior portal is established. Tissue-grasping forceps are used to obtain soft tissue specimens, which are sent to the laboratory for frozen section (if indicated), Gram stain, and culture and sensitivity testing. A shaver and cautery are used to perform a synovectomy and débridement of all involved areas throughout the glenohumeral joint. Depending on the severity of the infection, there may be severe damage to the chondral, osseous, or rotator cuff tissue ( Figs. 9.4–9.12 ).
