Accuracy of the Transpatellar Tendon Approach to Knee Arthrocentesis

Study Overview
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Brief Summary
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The purpose of this study is: To determine the accuracy of intraarticular placement with the transpatellar tendon approach as compared to the suprapatellar approach. Patients undergoing knee arthroscopy will be consented for study of the injection of the fluid into the joint prior to portal placement or commencement of knee replacement. Patients will be randomized to receive injections via the transpatellar tendon or superolateral approach. Using injectable contrast and fluoroscopy, the placement of injections into the knee will be evaluated for accuracy. Injection attempts with contrast fluid that uniformly coats the articular surface on sagittal and coronal radiographs will be counted as successful. A concentration of contrast fluid in extraarticular fat will be counted as a failure. Hypothesis: The rate of accuracy of intraarticular placement of the needle tip via the transpatellar tendon approach to knee aspiration is greater than that of the superolateral approach. To determine the distribution of contrast material with the transpatellar tendon and superolateral apporaches. Using a previously described evaluation technique of dividing the knee into seven compartments, sagittal and coronal fluoroscopy images will be evaluated to determine the distribution of contrast fluid. Hypothesis: Contrast injected into the knee via the trasnpatellar tendon approach will penetrate as many compartments of the knee as contrast injected via the superolateral approach.

Conditions
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Knee Aspiration

Intervention / Treatment
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* Procedure: Transpatellar Approach
* Procedure: Suprapatellar


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: undergoing elective arthroscopic surgery of the knee age greater than 18 years old and less than 80 years old able to consent to a research study Exclusion Criteria: allergy to contrast dye, iodine or shellfish currently pregnant acute fracture or dislocation

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Transpatellar Approach<br> | Procedure: Transpatellar Approach<br>* The transpateller approach for the injection of the dye will be used.<br>|
| Active Comparator: Suprapatellar Approach<br> | Procedure: Suprapatellar<br>* The suprapatellar approach will be used for the injection of the dye.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The development of an easier approach to aspirating the knee may lead to improved accuracy of intraarticular needle placement by less experienced practitioners and more anatomically difficult knees. |  | 1 time (intraop) |