Joint aspiration for diagnosis of chronic periprosthetic joint infection: when, how, and what tests?

Diagnosing chronic periprosthetic joint infection (PJI) requires clinical suspicion in combination with both serological and synovial fluid tests, the results of which are generally applied to validated scoring systems or consensus definitions for PJI. As no single "gold standard" test exists, the diagnosis becomes challenging, especially in the setting of negative cultures or equivocal test results. This review aims to address the workup of chronic PJI and considerations for clinical evaluation to guide treatment.

Functional Flexion Instability After Rotating-Platform Total Knee Arthroplasty.

Background: We sought to define "at risk" loading conditions associated with rotating-platform total knee arthroplasty (TKA-RP) implants that predispose to insert subluxation and spinout and to quantify tolerances for flexion-extension gap asymmetry and laxity in order to prevent these adverse events.

Methods: Biomechanical testing was performed on 6 fresh-frozen cadaveric limbs with a TKA-RP implant with use of a gap-balancing technique, followed by sequential femoral component revision with variable-thickness polyethylene inserts to systematically represent 5 flexion-extension mismatch and asymmetry conditions. Each configuration was subjected to mechanical loading at 0°, 30°, and 60°.

Surgeon Reimbursement Unchanged as Hospital Charges and Reimbursements Increase for Total Joint Arthroplasty.

Background: Despite increasing demands on physicians and hospitals to increase value and reduce unnecessary costs, reimbursement for healthcare services has been under downward pressure for several years. This study aimed to analyze the trend in hospital charges and payments relative to corresponding surgeon charges and payments in a Medicare population for total hip (THA) and knee arthroplasty (TKA).

Methods: The 5% Medicare sample database was used to capture hospital and surgeon charges and payments related to 56,228 patients who underwent primary THA and 117,698 patients who underwent primary TKA between 2005 and 2014.

Patients With Multiple Sclerosis are at Increased Risk for Postoperative Complications Following Total Hip and Knee Arthroplasty.

Background: Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease affecting the central nervous system. Patients with MS are living longer due to improved medical therapy and thus the demand for arthroplasty in this population will increase. The objective of this study is to evaluate MS as a potential risk factor for postoperative complications following total hip arthroplasty (THA) and total knee arthroplasty (TKA).