Lateral Knee Pain for More Than One Year — But Was It Really Bursitis?
Yesterday I saw a patient who had been suffering from lateral knee pain for over a year.
An ultrasound report suggested bursitis.
But during the examination, I felt that something did not completely fit the picture of a simple local knee inflammation.
The pain pattern was unusual.
Sometimes the pain stayed around the lateral knee, but at other times it radiated down toward the upper lateral calf. The patient also reported waking up at night because of the knee pain. Interestingly, there was no very obvious local tenderness around the knee joint itself.
Clinically, these details matter.
When the Symptoms Do Not Match the Imaging
Many knee problems can produce local pain.
But when pain starts radiating, when symptoms wake the patient at night, or when the examination findings do not fully match the scan result, I usually become more cautious.
In many cases, the real problem may not be exactly where the pain is felt.
That was the reason I decided to examine the nerve pathway further instead of focusing only on the knee joint.
Sensory Changes That Pointed Toward a Nerve Problem
During sensory testing, I found an area of reduced sensation over the upper lateral calf.
Then I performed a Tinel’s test around the lateral popliteal groove.
Tapping this area immediately reproduced radiating pain traveling down into the upper lateral calf.
Direct pressure over the groove produced the same symptom again.
At that point, the diagnosis started becoming much clearer.
This was not behaving like a simple bursitis case.
A Frequently Overlooked Diagnosis
The findings were more consistent with lateral sural cutaneous nerve entrapment, with the compression likely occurring around the lateral popliteal groove.
The lateral sural cutaneous nerve is a sensory branch of the common peroneal nerve. It mainly supplies sensation to the upper lateral calf.
Because it is a pure sensory nerve, patients usually do not present with muscle weakness.
This detail is clinically important.
If compression occurs before the nerve branches off from the common peroneal nerve, patients may also develop weakness of the foot or ankle.
But if the entrapment happens after the branch separates, symptoms may remain purely sensory.
Why This Case Was Not a Common Peroneal Nerve Entrapment
In this patient, there was no foot weakness, no foot drop, and no motor involvement.
The symptoms stayed localized to the sensory distribution of the lateral sural cutaneous nerve.
That helped narrow the diagnosis further.
This is why detailed neurological examination can sometimes be more valuable than simply relying on imaging findings alone.
Treatment Response
After acupuncture release around the lateral popliteal groove, the radiating pain reduced significantly during the treatment session.
The next step will be follow-up observation to assess the longer-term response.
At this stage, the immediate change in the radiating symptoms strongly supports the diagnosis.
examination and treatment video
What I Think Is Most Valuable About This Case
What I want to share is actually not that this diagnosis is “rare” or “mysterious.”
Once the clinical reasoning becomes clear, the case itself is not complicated.
The important part is being willing to question whether the original diagnosis fully explains the patient’s symptoms.
In clinical practice, many persistent knee pain cases are not simply “joint problems.”
Sometimes the real source may come from a small sensory nerve entrapment that is easily overlooked if the examination stays focused only on the knee itself.
A Reminder About Chronic Lateral Knee Pain
If a patient presents with:
- lateral knee pain
- radiating pain into the upper lateral calf
- numbness or altered sensation
- night pain
- unclear local tenderness
then it may be worth considering whether a nerve entrapment component is involved.
Especially when treatment focused only on the knee has not worked well.
Related previous cases:
📍PhD Win Acupuncture Clinic – Auckland
🌐 Book online: https://drwin.co.nz/online-booking/
中文微信：nzacupunctureclinic
Leave a reply