Pain in the back of the knee has several causes. One less common cause of posterior knee pain is low hamstring tendonitis — also called distal hamstring tendinopathy. So what is this condition, and how do we manage it?
This is one cause of pain behind the knee — see that hub for the full list.
What are the distal hamstring tendons?
The hamstring muscles are the biceps femoris, semitendinosus, and semimembranosus. These muscles form strong tendons that attach to the tibia and fibula at the lower part of the leg.
Overusing the hamstring tendons through excessive sport leads to tendonitis. Swelling and inflammation can form on the inside of the knee (semimembranosus) or the outside (biceps femoris). Most people who develop low hamstring tendonitis are runners or play sports that involve changes of direction and acceleration. Cyclists are also prone to overloading the hamstring tendons, especially with a change in cadence or intensity.
Symptoms of low hamstring tendonitis
Most cases present as pain in the back of the knee. The pain usually worsens at the start of activity and eases as you warm up. Its exact location can be hard to pinpoint — it may be deep, on the inside of the back of the knee (semimembranosus tendon), or on the outside near the head of the fibula (biceps femoris tendon). It’s often accompanied by general hamstring weakness.
We usually diagnose it on a thorough clinical assessment. Examining someone with distal hamstring tendinopathy shows tenderness at the back of the knee, and contracting the hamstring brings on the pain.
We often use imaging to confirm the diagnosis and exclude other causes of posterior knee pain — cartilage damage, calf muscle tears, and a Baker’s cyst. Pathology in the lumbar spine can also refer pain to the back of the knee.
How do we treat low hamstring tendonitis?
Like other tendon problems, treating distal hamstring tendinopathy is notoriously slow.
Simple treatments
We start with activity modification, rest from high-intensity sport, anti-inflammatory tablets such as ibuprofen, and a comprehensive strengthening programme for the hamstrings and the surrounding muscles. See a rehab specialist who can guide you through a step-by-step programme, including a return to sport. The rehab mirrors exercise therapy for proximal (high) hamstring tendonitis, outlined in more detail in that guide.
Shockwave therapy
We often use shockwave therapy for more complex cases that don’t settle with simple treatment. Focused or radial shockwave helps desensitise the tendon and allows strength progression. For hamstring tendonitis, we generally recommend higher-strength focused shockwave.
Ultrasound-guided injections
In more complex cases, we consider injection therapy. Traditionally, we inject a low dose of cortisone around the tendon to reduce pain and allow further rehab, directed by ultrasound to improve accuracy and minimise side effects. Because cortisone can damage the tendon, we use a lower dose than for joints.
An alternative is PRP (platelet-rich plasma). Withdraw blood from your arm, centrifuge it to separate the plasma from the heavier red blood cells, and inject the plasma into the area of tendonitis to promote healing. There’s good evidence for PRP in some tendons, such as those affected by tennis elbow, but little evidence for hamstring tendonitis. PRP can also worsen tendon pain in the short term (2–4 weeks) before improving it in the medium term (3–6 months). Recent evidence suggests that higher-concentration PRP systems, such as Arthrex ACP Max, get better results.
Frequently asked questions about low hamstring tendonitis
Where exactly is low hamstring tendonitis felt?
At the back of the knee, where the hamstring tendons attach. It can be on the inner side (semimembranosus) or the outer side near the fibular head (biceps femoris), which is why the exact spot can be hard to localise.
How is low hamstring tendonitis different from pes anserine bursitis?
They overlap and can coexist. Low hamstring tendonitis is felt at the back or inner back of the knee and worsens with hamstring loading; pes anserine bursitis is lower, on the inner shin just below the joint line. An ultrasound or MRI distinguishes them.
How long does low hamstring tendonitis take to recover?
Like most tendinopathies, it’s slow — often 3–6 months with a consistent strengthening programme. Rushing back to sport tends to prolong it.
What’s the best exercise for low hamstring tendonitis?
A progressive hamstring-strengthening programme, the same principles as for high hamstring tendinopathy — building load gradually under the guidance of a rehab specialist. Heavy, slow resistance work is generally well tolerated, even with some discomfort.
Can I keep running with low hamstring tendonitis?
Often, yes — many people train through stable, low-level pain while doing rehab. If the pain escalates or the tendon feels worse the next day, reduce the load and get it assessed.
Final word from Sport Doctor London about low hamstring tendonitis
Low hamstring tendonitis is common in active people and presents as pain at the back of the knee. See a sports doctor experienced in assessing and managing this condition for an accurate diagnosis and a structured rehab plan.
To book a one-stop knee assessment with Dr Masci in London, contact the team here or call +44 (0) 203 488 0350.
Leave A Comment