|Beitragstitel||Tarlov Cyst : A Diagnostic Of Exclusion. A Case Report.|
Tarlov cysts were first described in 1938 as an incidental finding at autopsy. The cysts are usually diagnosed on MRI, which reveals the lesion arising from the sacral nerve root.
Paulsen reported the incidence of Tarlov cysts as 4.6% in back pain patients (n=500). Only 1% of back pain patients (n=500) were symptomatic. The patient may present as low back pain, sciatica, coccydynia or cauda equina syndrome.
Symptomatic sacral perineural cysts are uncommon and it is recommended to consider tarlov cyst as a diagnostic of exclusion, in opposition to the avascular necrosis of the femoral head which is more common.
We report a case of a patient with voluminous bitaleral L5 and S1 Tarlov cyst, and right hip osteonecrosis to increase the awareness of this rare entity.
Study Design & Methods
A 57-year-old female, in good health, with a history of chronic low back pain since 20 years, presented suddently right buttock pain, low back pain and right inguinal fold pain for two months, with unability to walk and to sit down on the right buttock. The pain was not associated with specific time, posture or activity and it was not relieved by non steroidal antiinflammatory drugs (NSAID).
X-ray of the lumbosacral spine revealed asymetric discopathy L5-S1 and L3-L4 (Figure 1). X-ray of the right hip did not revealed anything (Figure 2). We asked for an MRI of the spine :
- Voluminous fluid-filled cystic lesion, arising from the fifth lombal nerve root on both side and measuring 1,2cm in diameter [Figure 3], from the first sacral nerve root on both side and measuring 3,3cm in diameter [Figure 4].
The MRI also show a part of the hip and incidentaly we discovered :
- Osteonecrosis Ficat 3 of the right femoral head [Figure 6].
The patient was taken for a total hip arthroplasty, by anterior approach (Uncemented Stem SPS evolution, uncemented cup April, bearing couple ceramic-ceramic). [Figure 7].
Patient appreciated relief of pain immediately after the surgery.
The current case show that even if we find a voluminous cysts we always have to eliminate other diagnosis (especially the frequent like osteonecrosis of the femoral head) and mostly in the case of unclear neurological perturbation. However in the case of our patient we discovered the hip osteoecrosis incidentally and in front of pain of the inguinal fold we should have request immediately an MRI of the the hip in addition to the spine MRI, even if she hadn’t any risk factors.