Above the Kneecap or Below It? Quadriceps vs Patellar Tendinopathy

Point at the sore spot with one finger. Above the kneecap or below it. That answer changes the exercises more than most people expect.

Here is what each tendon does, how the two are told apart, and why the loading position is the part that changes the plan.

Two tendons, one kneecap

The kneecap sits inside the tendon of the quadriceps muscle group. Above it, the quadriceps tendon connects the thigh muscles to the top of the patella. Below it, the patellar tendon runs from the bottom of the patella down to the shin bone.

Both transmit the same force. When the quadriceps contracts, tension passes through the tendon above the kneecap, through the bone, and out through the tendon below it. That shared line of pull is why pain from either one shows up in the same general area at the front of the knee.

The point of highest strain shifts with the angle of the knee, and that shift is the whole story here. A 2021 narrative review of anterior knee pain differential diagnosis states that the quadriceps tendon is preferentially loaded in deep flexion, and that this should guide physical therapy programmes. Patellar tendon loading occurs during eccentric quadriceps contraction, the controlled lowering phase of a movement.

Telling them apart

The first step is the location of the tenderness.

For patellar tendinopathy, the StatPearls overview of patellar tendinopathy identifies the inferior pole of the patella as the most commonly affected site. The 2021 review describes it as activity-related pain localised to the distal pole of the patella. Pressing on that spot reproduces the pain.

For quadriceps tendinopathy, pain sits at the superior border of the patella, and the examination shows localised tenderness in that same place.

The second step is the population. Patellar tendinopathy tracks closely with jumping. Approximately 45 percent of elite jumping athletes have symptoms at some point, and up to 14 percent of recreational jumping athletes. The 2021 review reports 45 percent prevalence in professional volleyball players and 32 percent in professional basketball players. Surface matters too: prevalence among athletes playing on concrete is 38 percent, compared with 20 percent on other surfaces.

Quadriceps tendinopathy also appears in people who do not jump. The 2021 review associates it with obesity, heavier weights, and increased height. Someone who lifts heavy through deep squat positions, or who carries more load through the knee in general, can develop it without ever playing a jumping sport.

What is actually happening in the tendon

Both problems are load-related tendon disorders, and the tissue picture is the same one described across tendinopathies.

The histopathology is degenerative rather than inflammatory. A study from two decades ago reported the absence of inflammatory cells in the tissue. That finding changed how these problems are treated. If the tissue is not inflamed, the goal shifts from calming inflammation to giving the tendon graded, progressive load so the tissue can adapt.

The same logic drives management of other load-related tendons, and the principles carry across, as covered in our guide to Achilles tendinopathy and heavy slow loading.

Staging helps set expectations. The Blazina classification for patellar tendinopathy describes four stages. Stage 1 is pain after activity. Stage 2 is pain at the onset of activity that subsides with warm-up and may recur with fatigue. Stage 3 is pain during activity and at rest with declining performance. Stage 4 is complete tendon rupture. Duration is described separately: acute is 0 to 6 weeks, subacute 6 to 12 weeks, and chronic beyond 3 months.

Progress is tracked with the VISA-P questionnaire, which demonstrates strong inter- and intra-observer reliability. Ultrasound is sometimes used: a tendon thickness of at least 7 mm predicted tendinopathy with a sensitivity of 81.3 percent and specificity of 95.6 percent, and a preseason thickness of 8 mm was highly predictive of symptomatic patellar tendinopathy during the season.

Why deep flexion is the key difference

This is the practical point that separates the two programmes.

If the painful tendon is the one below the kneecap, the loading that provokes and then rehabilitates it is eccentric quadriceps work. Slow lowering in a squat, controlled landings, decline squats. The tendon is under highest tension in that lowering phase.

If the painful tendon is the one above the kneecap, deep flexion is the position that loads it most. A programme built entirely around shallow-range eccentric work can leave that tendon barely challenged, which means it will not adapt. The 2021 review is explicit that the deep flexion preference should guide the physical therapy programme for quadriceps cases.

That is why the one-finger question at the start of the assessment is worth asking carefully. Two people with front-of-knee pain, given the same generic quadriceps programme, will get different results depending on which tendon is involved and what range the exercises actually cover.

What the loading evidence says

For patellar tendinopathy, the evidence has moved over time and it is worth knowing where it now sits.

Eccentric training has long been described as the treatment of choice, with the recommendation that it be tried for 12 weeks before surgical treatment is offered. That remains a reasonable baseline.

Newer work has broadened the options. Heavy slow resistance has been shown to be as effective as eccentric exercise in reducing pain and in fibre remodelling, with significantly higher patient satisfaction. Progressive tendon-loading exercises reduced symptom severity compared with eccentric exercises at the 24-week mark. A 2024 meta-analysis found that progressive loading with isometrics or heavy slow resistance was more effective than eccentric training alone. Our article on patellar tendinopathy and heavy slow resistance goes through what that programme looks like in practice.

Timing within the season matters. Eccentric decline squats performed in-season by volleyball players experienced a worsening of symptoms. The tendon is already receiving substantial load from training and competition, and adding a demanding eccentric programme on top can tip it the wrong way. That is a strong argument for isometric or heavy slow resistance work during competition, saving the most demanding loading for the off-season.

Rehabilitation is generally described in three stages: pain and load modulation first, then strengthening and load progression, then functional strengthening and return to sport. Movement of the knee under load also depends on what happens above and below it, which is why assessment usually looks at the hip and the ankle as well, the same reasoning used in our guide to patellofemoral pain in runners.

What happens if it is left alone

Tendon pain at the front of the knee has a habit of being tolerated for a long time, because it often warms up during activity and hurts afterwards instead.

The consequence shows in the numbers. Among athletes studied with patellar tendinopathy, 53 percent of symptomatic subjects had quit their sport, compared with only 7 percent of asymptomatic subjects. That gap is the argument for treating it as a real problem early rather than managing it with a warm-up and a strap.

The outlook with proper loading is good. Nonsurgical methods are reported as up to 90 percent effective, and surgery is considered only after 6 months of nonsurgical methods have failed.

When to get it looked at

Front-of-knee pain that has lasted more than a few weeks, that hurts at the start of activity, or that has started to affect how you perform is worth having assessed. Pain that is present at rest, or a clear decline in what you can do, corresponds to the later Blazina stages and should not be left.

Some situations need prompt medical attention rather than a physiotherapy booking: a sudden pop with inability to straighten the knee or to lift the leg against gravity, an obvious gap felt above or below the kneecap, or inability to bear weight after an injury. Those are calls to your physician or to Lions Gate Hospital, since complete tendon rupture is the final stage in the Blazina classification.

If your knee has been sore at the front and you want to know which tendon is involved and what loading it needs, book a 30-minute assessment and we will test it and build the programme around the right position. You can see what we treat or reach the clinic here.

This article is general information, not personal medical advice. A regulated practitioner can confirm whether the patterns described apply to you.

Sources

• Patellar Tendinopathy (Jumper's Knee), StatPearls, NCBI Bookshelf
• Narrative: Review of Anterior Knee Pain Differential Diagnosis (Other than Patellofemoral Pain) (Current Reviews in Musculoskeletal Medicine, 2021)
• College of Health and Care Professionals of BC public registry

This article is for general information only and does not constitute medical advice, diagnosis, or treatment. Individual presentations vary, and assessment findings and treatment plans differ from person to person. If you are experiencing severe symptoms, neurological changes (numbness, weakness, bowel or bladder changes), or a significant trauma, contact your physician or emergency services. Care at Medstar Sport Physio & Health is provided by practitioners registered with their respective British Columbia regulatory colleges.