Diagnostic Evaluation of the Knee in the Office Setting Using Small-Bore Needle Arthroscopy

Abstract

Arthroscopy is currently the gold standard for diagnosing intra-articular knee pathology. Magnetic resonance imaging (MRI) can be a clinical adjunct for diagnosis; however, it is not without its shortcomings. Although highly accurate, even advanced imaging misdiagnoses the condition in 1 in 14 patients with regard to anterior cruciate ligament pathology. Previous studies have indicated that MRI fails to identify meniscal pathology when one exists in 1 of every 10 cases, and diagnoses pathology when pathology truly does not exist in 1 of every 5 patients. In-office arthroscopy offers an alternative to formal diagnostic arthroscopy, with reduced cost and risk of complications. This is a technique article that discusses the use of small-bore needle arthroscopy in the office setting.

Figures

Fig 1

Office setup for preparation of in-office arthroscopy for the right knee. Note that the patient is supine with her knee at 90°. Tablet and sterile stand can be set up per the surgeon's preference. The patient can also be positioned sitting upright with the affected knee flexed to 90°.

Fig 2

Right knee. The medial and lateral portals are drawn out just off the patella tendon medially, and laterally 0.5 cm inferior to the inferior pole of the patella. A transpatellar tendon portal 1 cm inferior to the inferior pole can be used if necessary. Also, accessory superior lateral or superior medial portals can be used.

Fig 3

Insertion of a Mi-Eye probe into the lateral portal of the right knee. Note that the syringe connected to the probe and stopcock is in open position ready to distend the capsule. The patient is supine with the knee extended.

Fig 4

Just as in standard arthroscopy, the knee can be manipulated using varus force or a figure-of-4 position to visualize the lateral and medial compartments, respectively.

Fig 5

Three-tesla T2-weighted coronal (A) and sagittal (B) magnetic resonance image of a patient with chronic medial-sided right knee pain with minimal chondral damage on advanced imaging. In-office arthroscopy of the medial compartment (C) showed a grade IV chondral lesion on the medial femoral condyle after flexion of the knee to approximately 45° (D) viewed from the anterolateral portal.