Knee pain on the side, especially when bending, is a common issue that can range from a mild ache to sharp pain. Understanding potential causes is key to finding relief.
Common Causes of Side Knee Pain When Bending
Several conditions can cause pain on the side of the knee, particularly when bent. Identifying the specific cause is important for effective management.
Iliotibial Band (ITB) Syndrome is a frequent cause of outer knee pain, common in runners and cyclists. The iliotibial band is a thick tissue band running along the outside of the thigh to just below the knee. Repetitive knee bending can cause friction and inflammation where it rubs against the outer knee. Pain often appears around a 30-degree knee bend and worsens with activity or stairs.
Lateral Meniscus Tears also commonly cause pain on the side of the knee when bending. The meniscus is a C-shaped cartilage that acts as a shock absorber. A lateral meniscus tear affects the outer cartilage, often from twisting motions with a planted foot. Symptoms include tenderness along the outer joint line, swelling, difficulty bending or straightening the knee, and a clicking or locking sensation.
Lateral Collateral Ligament (LCL) Injuries involve the ligament on the outer knee that connects the thigh bone to the lower leg, stabilizing the joint. An LCL sprain or tear typically results from a direct impact to the inside of the knee or sudden twisting. Common symptoms include pain, swelling, and tenderness on the outside of the knee, often with instability. Stiffness and reduced range of motion, especially with bending, can also occur.
Osteoarthritis (OA) affecting the lateral compartment involves gradual cartilage wear on the outer side of the knee. This degenerative condition is more common in older individuals. As cartilage deteriorates, bones can rub, causing pain, stiffness, and reduced flexibility. Pain from lateral compartment OA often worsens with activity and bending, and may include swelling.
Initial Management at Home
Home management for side knee pain often starts with conservative measures to reduce discomfort. These steps are appropriate unless pain is severe or accompanied by other concerning symptoms.
Rest and activity modification are primary in the acute phase. Avoid activities that aggravate pain, such as running, jumping, or prolonged bending. Limiting knee use allows tissues to heal and prevents further damage.
Applying ice to the affected area helps reduce pain and swelling. Apply ice packs for 15 to 20 minutes every few hours, especially during the first 24 to 48 hours. Wrap the ice pack in a towel to protect skin.
Over-the-counter pain relief can help manage discomfort. NSAIDs like ibuprofen or naproxen reduce pain and inflammation. Acetaminophen also provides pain relief. Topical pain relievers, such as NSAID gels, can be applied directly to the painful area.
Gentle movement and stretching can be beneficial once acute pain subsides, but proceed cautiously. Maintaining mobility without aggravating pain helps prevent stiffness and improves circulation. Stretching surrounding muscles like quadriceps, hamstrings, and calves can improve flexibility and reduce tightness.
Elevating the injured knee above heart level can help reduce swelling by promoting fluid drainage.
Medical Evaluation and Treatment Options
When home care measures do not provide relief or if symptoms worsen, a medical evaluation becomes necessary. Certain signs indicate professional medical attention is immediately needed. This includes severe pain, inability to bear weight on the knee, significant swelling, a visible deformity, or persistent pain despite home care.
During a medical evaluation, a healthcare provider will conduct a physical examination of the knee, assess its range of motion, and discuss symptoms. Imaging tests, such as X-rays, MRI, or ultrasound, may be ordered to confirm a diagnosis and assess damage to bones or soft tissues.
Conservative treatment approaches are often the first line of professional intervention. Physical therapy is commonly recommended to strengthen muscles around the knee, improve flexibility, and restore proper biomechanics. Bracing may provide support and stability, especially for ligament injuries. Injections, such as corticosteroids, can reduce inflammation and pain. Hyaluronic acid injections, also known as viscosupplementation, can lubricate the joint and reduce pain, particularly for osteoarthritis.
Surgical considerations are typically reserved for cases where conservative treatments fail or for severe injuries. Significant meniscus tears causing locking or persistent pain may require surgical repair or removal. LCL injuries, especially complete tears or those causing instability, may necessitate surgical repair or reconstruction. The decision for surgery is made after assessing injury severity and patient health.