Why Your Knee Hurts When Going Downstairs

Posted by: in Knee Pain & Mobility on September 10, 2026

Woman experiencing knee pain while carefully walking downstairs and holding the railing.

Walking downstairs may seem like a simple task, but it places a surprising amount of demand on your knees. Each time you step down, the muscles around your hip and knee must control your body weight while your knee bends. If those muscles are weak, the kneecap is irritated, the joint is stiff, or your movement has changed, knee pain going downstairs may become a real problem. You might feel a sharp pain behind your kneecap, an ache along the inside of your knee, or a sense that the knee could buckle.

Knee pain when going downstairs is often connected to patellofemoral pain, sometimes called runner’s knee. However, arthritis, tendon irritation, a meniscus injury, bursitis, muscle weakness, or reduced mobility can create similar symptoms. The location of the pain and the way it began may offer clues, but a full evaluation is often needed to identify the cause.

Why Does Going Downstairs Put So Much Pressure on Your Knees?

Going downstairs requires your body to slowly lower itself from one step to the next. Your front thigh muscles, called the quadriceps, must work while they are lengthening to control that downward movement. This is known as an eccentric muscle contraction. Your kneecap also moves through a groove at the end of your thigh bone as your knee bends. The deeper the knee bends, the more demand is placed on the muscles and joint.

Your hips, ankles, feet, and core also help control the movement. If one area is weak, stiff, painful, or poorly coordinated, your knee may have to handle more stress. This is why knee pain on stairs is not always caused by a problem inside the knee alone.

Why Does My Knee Hurt Going Downstairs but Not Upstairs?

Going downstairs requires your leg to act like a brake. Your quadriceps must gradually slow your body as you lower your foot to the next step. Going upstairs also uses the quadriceps, but the muscles are working to lift your body upward. Some people have enough strength to push up a step but struggle to control the slower lowering movement required when coming down. Walking downstairs may also require more knee bend and balance. If your knee, hip, or ankle is not controlling the movement well, you may notice pain going down even when going up feels comfortable.

That difference can offer useful information during a physical therapy evaluation.

Common Causes of Knee Pain When Going Downstairs

Several knee conditions can make stairs painful. Some are caused by a recent injury, while others develop gradually because of activity changes, weakness, stiffness, or repeated strain.

Patellofemoral Pain Syndrome

Patellofemoral pain syndrome is one of the most common causes of pain at the front of the knee. It affects the area around or behind the kneecap. The kneecap normally glides through a groove at the end of the thigh bone. If the surrounding tissues become irritated or the knee is exposed to more stress than it can currently tolerate, bending the knee under load may become painful.

Patellofemoral pain can develop after:

Increasing your walking or running distance
Starting a new workout program
Adding more hills or stairs
Returning to sports
Changing your footwear
Spending more time kneeling or squatting
A period of reduced activity
An injury to the knee, hip, or ankle

Pain may be felt behind, around, or underneath the kneecap. It is often worse when using stairs, squatting, running, jumping, or sitting with the knee bent for a long time. You may also notice grinding, clicking, or popping. These sounds do not always mean that the joint is damaged. They become more important when they occur with pain, swelling, locking, or instability.

Quadriceps Weakness

Your quadriceps muscles help straighten the knee and control your body as you lower yourself. If these muscles are weak, injured, or fatigued, your knee may not absorb force as effectively. You may drop quickly onto the next step, shift your body to one side, turn your foot outward, or rely heavily on the railing.

Quadriceps weakness can develop after:

Knee surgery
A knee injury
A period of reduced activity
Wearing a brace or cast
Avoiding the painful leg
Illness or bed rest
Ongoing knee pain

Pain can also reduce how well the quadriceps work. This means weakness may be both a cause and a result of knee pain.

Hip Weakness

The muscles around your hips help control the position of your thigh and knee as you step down. If your hip muscles are not providing enough strength or control, the knee may move inward during the lowering motion. This can increase the demand around the kneecap and make stairs uncomfortable.

Hip weakness is not always easy to notice during normal walking. It may become more obvious during single-leg tasks, including:

Going downstairs
Stepping off a curb
Performing a lunge
Running
Landing from a jump
Standing from a low chair

Strengthening the hip may be one part of a knee rehabilitation program, but exercises should be selected based on the person’s full evaluation.

Knee Osteoarthritis

Knee osteoarthritis involves changes in the cartilage, bone, and other tissues within the joint. It can cause pain, stiffness, swelling, grinding, and reduced mobility. Arthritis pain may be more noticeable when using stairs, standing after sitting, walking for long periods, or placing more weight on the affected leg. Some people feel pain throughout the knee, while others feel it mainly along the inside or front of the joint. Knee arthritis can make daily activities more difficult, but movement does not automatically make the condition worse. Appropriate strengthening, mobility work, and activity changes can help many people improve their function and confidence.

Patellofemoral Arthritis

Patellofemoral arthritis specifically affects the joint between the kneecap and thigh bone. It often causes pain at the front of the knee. Kneeling, squatting, climbing stairs, and going downstairs may become difficult because these activities place greater demand on the kneecap joint. Some people also notice stiffness, swelling, grinding, or a feeling that the kneecap is catching during movement.

Patellar Tendon Irritation

The patellar tendon connects the kneecap to the shinbone. It helps transfer force from the quadriceps so you can straighten your knee, jump, run, and use stairs. Patellar tendon pain is usually felt just below the kneecap. It may develop after repeated jumping, running, lifting, or a sudden increase in activity. At first, pain may improve as you warm up and return after activity. As the condition becomes more irritated, stairs, squats, standing from a chair, and normal walking may also become painful.

Quadriceps Tendon Irritation

The quadriceps tendon connects the quadriceps muscles to the top of the kneecap. When this tendon becomes irritated, pain is often felt just above the kneecap. It may become more noticeable when bending the knee under pressure, including during stairs, squats, lunges, or jumping. A sudden injury can also damage the quadriceps tendon. Seek prompt medical care if you felt a pop, developed rapid swelling, or cannot straighten the knee.

Meniscus Injury

The menisci are pieces of cartilage that help cushion and stabilize the knee. A meniscus injury can happen during twisting, pivoting, deep bending, or a sports injury. Meniscus tissue can also change gradually over time.

Possible symptoms include:

Pain along the inside or outside of the knee
Swelling
Catching or locking
Pain when twisting
Difficulty fully bending or straightening the knee
A feeling that the knee may give way
Pain during stairs or squatting

Pain on stairs does not automatically mean you have a torn meniscus. A professional evaluation can help determine whether your symptoms fit a meniscus injury or another knee condition. Locking, catching, or buckling that worsens during walking and squatting may raise more concern for a meniscus problem.

Pes Anserine Bursitis

The pes anserine bursa is a small fluid-filled sac located along the inner side of the knee, slightly below the joint. When this area becomes irritated, you may feel pain or tenderness on the inside of the upper shin. Symptoms may worsen when using stairs, rising from a chair, exercising, or lying with your knees touching. The painful spot is usually lower and farther toward the inside of the leg than typical kneecap pain.

The iliotibial band, often called the IT band, is a thick band of tissue that runs along the outside of the thigh. Irritation near the outside of the knee can develop during repeated bending and straightening, particularly with running, hiking, or cycling. Going downstairs may become painful because the knee repeatedly bends while supporting your weight. IT band-related pain is usually felt on the outer side of the knee rather than directly behind the kneecap.

Patellar Instability

Patellar instability occurs when the kneecap does not remain securely within its groove. It may shift farther than normal or partially move out of place. You may feel as though your kneecap is slipping, moving, or giving way. The knee may feel especially uncertain during stairs, turning, squatting, or single-leg activities. A previous kneecap dislocation can increase the likelihood of ongoing instability. Your physical therapist may evaluate kneecap mobility, leg strength, balance, and how your knee moves during a step-down task.

Ankle Stiffness

Your ankle needs to bend as your body moves forward and downward over your foot. If ankle mobility is limited, your body may compensate by turning the foot outward, allowing the knee to move inward, lifting the heel, or shifting weight to the other leg. These changes may increase stress around the knee. An ankle problem may be especially relevant if you previously had an ankle sprain, wore a boot or cast, or notice stiffness when squatting.

Pain Referred From the Hip or Lower Back

Not every pain felt near the knee starts in the knee. The hip or lower back may sometimes send pain into the thigh or knee. Nerve irritation can also cause aching, burning, tingling, numbness, or weakness in the leg. Your physical therapist may examine your hip and back if your symptoms do not follow a typical knee pattern or if you have pain in more than one area.

What Does the Location of Your Knee Pain Mean?

The location of your pain may offer clues, but it cannot confirm a diagnosis by itself.

Pain in Front of the Knee

Pain around or behind the kneecap is commonly associated with patellofemoral pain or patellofemoral arthritis. Pain directly below the kneecap may involve the patellar tendon. Pain directly above it may involve the quadriceps tendon.

Pain on the Inside of the Knee

Inner knee pain may be connected to the meniscus, arthritis, a ligament, or pes anserine bursitis. The exact location matters. Pain directly along the joint line may create a different concern than tenderness several inches below the knee.

Pain on the Outside of the Knee

Outer knee pain may involve the IT band, meniscus, joint, or surrounding muscles and tendons. It can also develop when changes at the hip or foot affect how the leg moves.

Pain Behind the Knee

Pain behind the knee may come from a muscle or tendon, swelling inside the joint, a Baker’s cyst, or another condition. Sudden calf or back-of-knee pain with swelling, warmth, redness, or trouble breathing requires urgent medical attention because it could be related to a blood clot.

Why Does My Knee Move Inward When I Step Down?

Some people notice that their knee moves toward the other leg when they walk downstairs. This can happen because of changes in strength, balance, mobility, coordination, or foot position.

Possible contributing factors include:

Reduced hip strength
Limited ankle mobility
Poor balance
Foot or ankle instability
Pain-related movement changes
Difficulty controlling the thigh
Fatigue

Knee movement is not automatically harmful. However, if the movement occurs with pain or poor control, a physical therapist may help you improve strength and find a more comfortable way to use stairs.

Should I Avoid Stairs if My Knee Hurts?

You may need to temporarily reduce how often you use stairs if each trip causes sharp or increasing pain. However, completely avoiding stairs and other knee movement for a long period may lead to more weakness and stiffness.

If stairs are necessary, try the following temporary changes:

Use the handrail for support
Move slowly and avoid dropping onto the lower step
Place your full foot on each step
Take one step at a time if needed
Reduce how much you carry
Avoid rushing
Keep the stairway well-lit
Wear supportive footwear

These changes may help you manage symptoms, but they do not replace an evaluation when pain continues.

Which Leg Should Lead When Going Downstairs?

If one knee is painful, many people find it easier to step down first with the painful leg while the stronger leg controls the lowering movement. A common reminder is, “Up with the good, down with the bad.” This means the stronger leg leads when going upstairs, and the painful leg leads when going downstairs. This pattern is intended as a temporary strategy. It may not be appropriate for every injury, especially if you have balance problems, weight-bearing restrictions, recent surgery, or instructions from a medical provider.

Always use a railing when needed.

Should You Exercise a Knee That Hurts on Stairs?

Appropriate exercise can often help knee pain, but the correct starting point depends on the cause and severity of your symptoms.

A physical therapist may begin with exercises that improve:

Quadriceps strength
Hip strength
Calf strength
Knee mobility
Ankle mobility
Balance
Single-leg control
Tolerance for bending the knee
Control during step-down movements

Exercises should be progressed gradually. Starting with deep squats, heavy lunges, repeated stairs, or high step-downs may increase pain if the knee is not ready for that level of demand. Mild discomfort during an exercise is not always harmful, but pain should not continue getting worse during the activity or remain significantly elevated afterward.

When Should You Have Knee Pain Evaluated?

Consider scheduling a physical therapy evaluation if:

Pain continues for more than several days
Pain returns every time you use stairs
You are avoiding normal activities
Your knee feels weak or unstable
You rely heavily on the railing
Pain interrupts your sleep
Your knee is swollen
You cannot fully bend or straighten it
The knee catches, locks, or gives way
Symptoms began after a fall or twisting injury
The problem is getting worse instead of better

You do not need to wait until knee pain becomes severe. An early evaluation may help identify strength, mobility, and movement problems before they become more limiting.

When Knee Pain Needs Urgent Medical Attention

Seek prompt medical care if:

You cannot put weight on the leg
The knee looks deformed
You heard a pop during a significant injury
The knee becomes very swollen soon after an injury
The knee is completely locked
You cannot straighten the leg
The knee repeatedly gives way
You have redness, warmth, fever, or signs of infection
Your foot becomes cold, pale, blue, or numb

Seek urgent medical care for sudden calf or back-of-knee pain with swelling, warmth, redness, chest pain, or trouble breathing.

How Physical Therapy Can Help Knee Pain on Stairs

A physical therapist can evaluate why going downstairs is painful rather than focusing only on the spot that hurts.

Your evaluation may include:

Knee range of motion
Hip, knee, and ankle strength
Kneecap mobility
Balance
Walking pattern
Foot and ankle movement
Squatting
Stepping up and down
Single-leg control
Your work, exercise, and activity demands
Your history of injuries or surgery

Your physical therapist may watch how your knee, hip, and foot move together during a step-down. This can help identify where you are losing strength, control, balance, or mobility. Treatment may include targeted strengthening, mobility exercises, balance training, hands-on care, activity changes, taping, movement retraining, and a personalized home exercise program. The goal is not only to reduce pain. It is also to help you feel stronger and more confident when using stairs, walking, exercising, and completing daily activities.

Get Help for Knee Pain in Maine

Going downstairs should not feel like a task you need to avoid or carefully plan around. At Reform Physical Therapy, we provide personalized, one-on-one care for knee pain. Your physical therapist will examine your knee while also looking at your hips, ankles, balance, strength, and movement patterns. Whether you want to use stairs comfortably, return to running, get back to work, play a sport, or move through your day with less worry, your treatment plan will be built around your needs.

Reform Physical Therapy serves patients in Topsham, Brunswick, Freeport, Yarmouth, South Portland, Kennebunk, and Eliot.

Learn more about knee pain treatment or contact Reform Physical Therapy to schedule an evaluation.