"Intra-articular Hyaluronic Acid Injection for Accelerating Functional Recovery After Knee Arthroscopy"

"Intra-articular Hyaluronic Acid Injection Significantly Accelerates Functional Recovery After Knee Arthroscopy: A Prospective Randomized Controlled Trial"

This study evaluates the effectiveness of intra-articular hyaluronic acid (HA) viscosupplementation and oral chondroitin sulfate (CS) supplementation, in combination with standard postoperative rehabilitation, on functional recovery, pain reduction, and quality of life following knee arthroscopy for medial meniscus injury. Knee arthroscopy is commonly performed for meniscal tears, but the extensive joint irrigation during the procedure removes naturally occurring synovial fluid, potentially prolonging recovery. Hyaluronic acid is the main component of synovial fluid and plays crucial roles in joint lubrication, shock absorption, and cartilage protection. This prospective, randomized, three-arm controlled trial will enroll approximately 290 patients undergoing arthroscopy for medial meniscus injury. Participants will be randomized into three groups: (1) standard rehabilitation alone (Control), (2) rehabilitation plus oral CS supplementation (1200mg CS and 40mg Vitamin C daily for 12 weeks), or (3) rehabilitation plus two intra-articular HA injections (Biolevox™ HA 2.2%, administered at 2 weeks and 6 weeks post-arthroscopy). The primary outcome is knee function assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS) at 12 weeks. Secondary outcomes include quality of life (WHOQoL-BREF questionnaire) and safety assessments. The study hypothesis is that viscosupplementation with medium molecular weight HA will result in superior functional outcomes compared with oral supplementation or standard rehabilitation alone.

Knee arthroscopy is the most commonly performed orthopedic procedure. Although it offers advantages over open surgery, including reduced postoperative pain and faster recovery, the procedure inevitably involves extensive joint irrigation which removes naturally occurring synovial fluid. Synovial fluid plays a crucial role in joint lubrication and shock absorption. Its reduction following arthroscopy increases friction between articular surfaces, intensifying pain and potentially prolonging rehabilitation. Recovery typically requires 4-6 weeks, during which patients may experience persistent pain and limited joint function. Viscosupplementation with hyaluronic acid (HA) has emerged as a promising approach to addressing post-arthroscopic joint dysfunction. HA is the main non-protein component of synovial fluid, forming a protective layer on articular cartilage, reducing friction and helping maintain tissue resistance to compressive forces. Beyond mechanical effects, HA provides biological benefits including stimulation of endogenous HA synthesis, reduction of proteoglycan loss, and protection of chondrocytes from apoptosis. Oral chondroitin sulfate (CS) supplementation has also been proposed as an adjunctive therapy, with proposed mechanisms including support for cartilage homeostasis through stimulation of proteoglycan and collagen synthesis.

Inclusion Criteria:

Age 18-65 years at time of enrollment

• Scheduled for knee arthroscopy for treatment of medial meniscus injury
• Torn medial meniscus with various morphology confirmed by magnetic resonance imaging (MRI)
• Positive clinical examination findings specific for medial meniscus tear OR mechanical symptoms (locking, catching)
• Failed conservative treatment for at least 3 months including physical therapy and/or anti-inflammatory medications
• Grade 0 or Grade 1 osteoarthritis according to Kellgren-Lawrence radiographic classification scale at baseline visit
• Able and willing to provide written informed consent
• Able to comply with study procedures and attend all follow-up visits
• Willing to adhere to postoperative rehabilitation protocol

Exclusion Criteria:

• Prior surgery on the ipsilateral knee (except previous knee arthroscopy for partial meniscectomy and/or chondroplasty)
• Prior surgery on the contralateral knee (except previous knee arthroscopy for partial meniscectomy and/or chondroplasty)
• Intraoperative diagnosis of anterior cruciate ligament (ACL) injury requiring reconstruction
• History of concomitant knee procedures including: ligamentous repair or reconstruction, high tibial osteotomy, distal femoral osteotomy, hardware removal, irrigation and debridement for infection, microfracture procedures, autologous chondrocyte implantation (ACI), osteochondral autograft transfer (OATS), or osteochondral allograft transfer
• Axial knee deformity (varus or valgus malalignment)
• Radiological signs of knee osteoarthritis Grade 2 or higher on Kellgren-Lawrence scale
• Inflammatory arthritis (rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, etc.)
• History of septic arthritis in either knee
• Known hypersensitivity or allergy to hyaluronic acid products, chondroitin sulfate, or any study product components
• Active infection or skin disease at the injection site
• Bleeding disorders or current anticoagulation therapy that cannot be safely interrupted
• Pregnancy or lactation - Current participation in another interventional clinical trial
• Any condition that, in the opinion of the investigator, would compromise the participant's ability to participate in the study or potentially confound study results