1. UNCOMMON PRESENTATION OF BILATERAL PIGMENTED VILLONODULAR SYNOVITIS
ABSTRACT ID : IRIA 1149

2. BACKGROUND
Pigmented Villonodular Synovitis (PVNS)- Benign proliferative disorder that affects synovial lined joints, bursae, and tendon sheaths .
PVNS is a slow-growing lesion of uncertain etiology arising from the synovial membrane
Two primary forms –
a) Diffuse form affects the entire synovial lining of a joint, bursa or tendon sheath, involves the large joints.
B)Localized form - occurs around the tendon sheaths of small joints.

3. Common presentation in 3rd to 4th decade.
The disease may show extraarticular soft tissue involvement, along with a primary intraarticular process.
PVNS involving the shoulder joint is uncommon and bilateral involvement of shoulder is < 1 % cases.
Common presentation in 3rd to 4th decade.
It is usually monoarticular, polyarticular involvement is rare.
Commonly involved joints- knee/ ankle/ hip/ finger joints.
Shoulder joint involvement is extremely rare.

4. Localized - Most common and involves small joints of the hand/feet.
Two types:
Diffuse - Affects the entire synovial lining of the joint, bursa, or tendon, involves the large joints such as the knee and hip joints.
Localized - Most common and involves small joints of the hand/feet.
The extra-articular form of PVNS is very rare and often
represents an extension of a primary intra-articular process.
CLINICAL FEATURES:
--Pain of long duration/ Decreased range of motion/ Joint locking/ swelling of joint.
--Extra articular present with soft-tissue mass.
--Slight female predominance seen.

5. ETIOLOGY:
--Inflammatory process
--Repeated hemorrhage into the joint
--Repetitive mild trauma
--Neoplasia
--Disorder of lipid metabolism
--Genetic rearrangement in both localized and diffuse types of PVNS : chromosome 1p11-13, a site for CSF-1 gene, which most commonly fuses to COL6a3 on chromosome 2q35.

6. CASE REPORTS A 41 yr old female came with complaints of –
Pain and swelling in both shoulders for past 5 months.
Shoulder joint movement restriction since 5 months.
Past history- No history of trauma.
Not a known case of Tuberculosis/ Hypertension/ Diabetes mellitus.
Previous CT imaging was done but images were not available.
Family history- Not significant

7. EXAMINATION GENERAL EXAMINATION: - Afebrile, vitals stable
SYSTEMIC EXAMINATION:
OTHER SYSTEMS-
RS/ CVS/ CNS – No abnormality detected.
P/A- Soft.
LOCAL EXAMINATION:
-Inspection : Bilateral shoulder joint mild swelling.
Shoulder joint movement was restricted.
-Palpation: Bilateral warmth with tenderness present.
Bilateral shoulder joint soft – firm mobile masses .
Measurement- 5 x 4cm in right shoulder.
10 x 8cm in left shoulder.
CLINICAL DIAGNOSIS: ? Tubercular villonodular synovitis.

8. IMAGING
PLAIN RADIOGRAPH of both the shoulder joints showing homogenous soft tissue opacity infiltrating around the humerus.

9. ULTRASOUND of both shoulder showing markedly thickened hypo echoic synovium with nodular and villous projections with multiple heterogeneous echogenic masses

10. RT T1W Cor RT T2W Cor RT PDW Cor
Gross distension of the sub acromial  sub deltoid bursa (red arrows) which is filled with fluid and a large extra articular multilobulated heterogeneous signal intensity lesion appearing low to intermediate signal intensity in T1w images (green arrows) with variable signal intensity in T2w images (yellow arrows) within it, superior to supraspinatus.

11. Post contrast, the lesion shows intense contrast enhancement.RT
T2 FFE Cor RT
T1c + Gd Cor
T2 FFE sequence showing few blooming artefacts (yellow arrow) signifying hemosiderin.
Post contrast, the lesion shows intense contrast enhancement.

12. RT PDW Axial RT T1c + Gd Cor
PDW sequence showing few similar signal intensity lesions in the intra-articular region (yellow arrows) and supraspinatus muscle. Few bony lesions also noted (green arrow).
Post contrast sequence showing similar enhancement pattern as the extra-articular component.

13. MRI PDW axial sequence showing few subchondral cystic changes in the head of humerus (yellow arrow).
Few lesions showing similar signal intensity and enhancement pattern also seen in left head of humerus.

14. DIAGNOSIS
Enhancing proliferative synovium with a lobulated mass in the subacromial subdeltoid bursa
Erosions in the humeral head with minimal involvement of the shoulder joint and subscapularis muscle
Features suggestive of extraarticular and intra articular form of diffuse type of pigmented villonodular synovitis

15. DIFFERENTIAL DIAGNOSIS
Primary synovial chondromatosis
--T2: high signal
--loose bodies formation
Lipoma arborescens
--T2: high signal; will saturate on fat suppressed sequences
Synovial sarcoma
--Mass around, but outside of, joint
--Frequently calcify
Degenerative arthritis
--Joint space narrowing
--Subchondral sclerosis

16. CONCLUSION
PVNS involvement of the shoulder joint is a rare location with bilateral joints involved is uncommon.
Findings of both intraarticular and extraarticular involvement is a rare presentation
The radiologic appearances of intraarticular PVNS, particularly its MR imaging findings, are frequently pathognomonic.
MR imaging is the optimal modality to depict and define the intraarticular and, particularly, extraarticular disease extent in order to guide complete surgical excision

17. REFERENCES
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