What’s in the web for family physicians – Management of knee pain

Wilbert WB Wong 王維斌，Alfred KY Tang 鄧權恩

Knee pain is a common presenting problem of patients in our everyday practice. It may be the result of an injury, such as a ruptured ligament or torn cartilage. Medical conditions including arthritis, gout and infections also can cause knee pain.

Most minor knee pain respond well to self-care measures. Physical therapy and knee braces also can help relieve knee pain. In some cases, however, the knee may require injection or surgical repair.

Knee examination

This is a very educational site for family physicians on examination of the knee joint. Its emphasis on both functional and anatomical relevance makes it a good reference when doing revision on the topic. Illustrations and animations are included to facilitate the understanding of different maneuvers in examination of the knee, including useful maneuvers like MacMurray Test or Appley Grind test. The rationale for each aspect of the examination is addressed and relevant pathophysiology discussed. Correlation images of gross anatomy are incorporated in different segments. Video clips of selected examination maneuvers and findings are available along the protocols.

Imaging of knee pain

Many patients with knee pain have a history of trauma. In older patients, acute pathology is usually superimposed on chronic degenerative osteoarthritis. The knee is most commonly affected by sports injuries. When a fracture is suspected, an X-ray is recommended as the initial investigation This review published in the Australian Journal of General Practice in 2020 with discussions on the approach to imaging of the knee with reference to Diagnostic Imaging Pathways and illustrate some of the conditions that may be encountered. There are also discussions on post-traumatic pain and monoarticular arthritis, describing some of the common findings and disease patterns shown on imaging.

A knee effusion is an indirect sign of injury. On X-ray it is best seen in the suprapatellar recess. Of importance is the recognition of a fat-fluid level in the effusion, known as a lipohaemarthrosis. This represents fat that has escaped from the bone marrow into the joint, which is a specific sign indicating an intraarticular fracture.

Clinical effectiveness of patella mobilisation therapy

Patellar mobilization therapy is a combination of manual therapy and home-based exercise, and can be very useful to patients with knee osteoarthritis. It helps to reduce pain and improve function and quality of life for patients with knee osteoarthritis.¹

A video can be found in YouTube demonstrating the patellar mobilization therapy (https://www.youtube. com/watch?v=XxTfaKflyaois) prepared by the team in 2019. It also explains the background theory on how the technique helps in improving the management of osteoarthritis of the knee joint.

Anterior knee pain

Anterior knee pain is common in elderly patients. The reason for anterior knee pain has been suggested to be multifactorial with patella abnormalities or extensor mechanism disorder leading to patellar malalignment during flexion and extension of the knee joint.

Weakness of the quadriceps muscle is usually present in the majority of anterior knee pain patients. Hypotrophy and reduced activity of the vastus medialis are often found, which result in an imbalance between vastus medialis and vastus lateralis.

Some home exercise for knee pain are available in the video【居家運動】膝關節運動 (https://www.youtube.com/watch?v=SY7S1M03Iag) produced the Pain Relief Project for the Seniors run by The Chinese University of Hong Kong. It includes different exercise programs designed with demonstration by registered physiotherapist. These exercise help to bring pain relief and better range of movement for the patient.

Exercise to improve the balance between vastus medialis and vastus lateralis can restore normal gait, and decrease loading of the patello-femoral joint, hence reduce pain and improve range of motion.

Guideline for the management of osteoarthritis of the hand, hip, and knee

This is the latest set of guidelines developed by The American College of Rheumatology in 2019. It provides insight for clinicians making treatment decisions for the management of osteoarthritis.

Based on evidence, recommendations were made in some pharmacological and non-pharmalogical approaches for osteoarthritis on different parts of the body. Recommendations are categorized into ʻstrongʼ and ʻconditionalʼ depending on the joint involved and different risk factors.

For example, presence of conditional recommendations were made for balance exercises, yoga, cognitive behavioral therapy, patellofemoral bracing for patellofemoral knee OA, acupuncture, thermal modalities, radiofrequency ablation for knee OA, topical NSAIDs, intraarticular steroid injections and chondroitin sulfate for hand OA, topical capsaicin for knee OA, acetaminophen, duloxetine, and tramadol.

This guideline is most useful to clinicians and patients making treatment decisions on management.

Total knee replacement

The website offers patient educational materials on the how treatment decisions are to be made on total knee replacement. It is usually based on the pain and disability from the arthritis influencing the quality of life and daily activities of the patient. Those who decide to proceed with surgery commonly report that their symptoms keep them from participating in activities that are important to them like walking, taking stairs, working, sleeping, etc.), and that nonoperative treatments have failed. Some frequently asked questions on the surgery are answered at the website.

There is also a video titled ʻKnee Replacement Surgery: a patient journeyʼ (https://www.youtube.com/watch?v=Y7dQKn3jrbs) available on YouTube prepared by the American Association of Hip and Knee Surgeons in 2020.

This video explains knee anatomy and how different joint disease indicates whether a partial knee replacement or a total knee replacement is needed.

Efficacy of intra-articular hypertonic dextrose (Prolotherapy) for knee osteoarthritis: a randomised controlled trial

Prolotherapy is an injection therapy used to treat chronic painful musculoskeletal conditions. Hypertonic dextrose prolotherapy has historically been understood to facilitate healing and subsequent pain control through tissue proliferation potentially mediated by an inflammatory mechanism.²

The standard prolotherapy injection protocol involves a whole joint approach with both intra-articular injections into synovial spaces and extra-articular injections at soft tissue bony attachments.

It requires intensive training on the skillset for practitioners and may induce much discomfort to the recipient. This study simplifies the injection protocol to a course of intra articular injections with hypertonic dextrose.

Intra-articular dextrose prolotherapy injections reduces pain, improves function and quality of life in patients with knee osteoarthritis compared with blinded saline injections. The procedure is more straightforward and safe, and hence with better adherence and higher satisfaction level.