From the Research
Intraarticular knee injections should be performed lateral to the patellar tendon, as this approach has been shown to have a higher accuracy rate and is generally preferred. When performing a knee injection, the most common technique is to access the joint from the lateral side of the patellar tendon with the knee flexed at 90 degrees. This lateral approach is favored because it typically provides easier access to the joint space and avoids the infrapatellar branch of the saphenous nerve, which runs medially and could potentially be injured during a medial approach.
Key Considerations
- The lateral approach tends to be more comfortable for patients and has a higher success rate for entering the joint space accurately, as demonstrated by a study published in the Journal of the Medical Association of Thailand = Chotmaihet thangphaet 1.
- The accuracy rate of intra-articular needle placement was highest (77.3%) using the lateral mid-patellar approach, followed by the anterolateral approach (63.6%) and lowest in the anteromedial approach (31.8%) 1.
- However, in certain clinical situations where lateral access is difficult (such as significant lateral compartment osteoarthritis or anatomical variations), a medial approach can be used as an alternative, as suggested by a study published in Acta orthopaedica et traumatologica turcica 2.
Important Factors
- Proper positioning, sterile technique, and accurate needle placement into the joint space are crucial for a successful injection, regardless of the approach used.
- The choice of approach may depend on individual patient anatomy and the specific clinical situation, and should be determined on a case-by-case basis.
- The most recent and highest quality study, published in 2020, does not directly address the approach for intraarticular knee injections, but highlights the importance of proper technique and patient selection for injection therapies in the treatment of patellar tendinopathy 3.