Keywords
arthroscopy - shoulder - synovial chondromatosis - synovial membrane
Introduction
Synovial chondromatosis (SC) is an exceptional arthropathy, usually monoarticular,
resulting from the proliferation and metaplasia of synovial tissue and the formation
of loose cartilaginous bodies in the tendon sheath or joint spaces.[1]
[2]
[3] The involvement pattern includes diarthrodial joints, especially the knee, hip,
and elbow; descriptions of shoulder involvement are scarce in the literature.[2] SC etiology remains unknown, and the highest SC incidence occurs in the third to
fifth decade of life. In addition, SC is three times more common in men.[3] The clinical picture consists of pain, crepitus, edema, and joint movement limitation,[2] often with no apparent cause.[1] Malignant transformation is uncommon, and there is no direct relationship with trauma
or inflammatory processes.[4] Clinical diagnosis is difficult, as history and physical examination findings are
not specific. Therefore, imaging methods, including radiography, computed tomography,
and magnetic resonance imaging (MRI), become essential to identify the different types
of SC lesions and stages.[5] Diagnostic confirmation relies on histological examination of the synovial tissue,
and surgery is the treatment of choice for symptomatic patients.[1]
[3]
Case Reports
Case 1: A 62-year-old female patient with a history of pain in her right shoulder
after exertion. On examination, the shoulder presented mild edema and limited movement.
The Neer impingement test and the Jobe and Speed tests were positive. Radiographs
showed signs of impingement and calcifications. MRI revealed a rupture of the supraspinatus
tendon and multiple calcifications in the bursa measuring 0.4 to 1.2 cm ([Figs. 1] and [2]). The patient underwent video arthroscopic surgical treatment consisting of synovectomy,
chondroma removal, and supraspinatus lesion repair. The anatomopathological examination
confirmed synovial chondromatosis. The patient started physical therapy two weeks
after surgery. During the outpatient follow-up, she presented improvement in pain,
range of motion, and strength in her right shoulder.
Fig. 1 Magnetic resonance imaging of the shoulder (coronal view, T2-weighted image).
Fig. 2 Magnetic resonance imaging of the shoulder (axial view, T2-weighted image)
Case 2: A 56-year-old female patient with a history of pain in her right shoulder.
The physical examination revealed mild edema, limited movement, and a positive Jobe
test. Radiographs showed signs of impingement and a hooked acromion with a spur. MRI
revealed intense proliferative synovitis with small intra-articular nodules in the
axillary recesses, bursitis, supraspinatus tendon rupture, extensive partial tear
of the subscapularis tendon, and ruptured tendon of the long head of the biceps. The
patient underwent video arthroscopic treatment for supraspinatus tendon injury repair,
synovectomy, subacromial decompression, and removal of multiple loose bodies ([Figs. 3], [4], and [5]). The anatomopathological examination confirmed synovial chondromatosis. The patient
began physical therapy rehabilitation one month after surgery. Pain improved immediately
after surgery, and shoulder function improved after six months of rehabilitation.
Fig. 3 Intra-articular arthroscopic view.
Fig. 4 Subacromial arthroscopic view.
Fig. 5 Macroscopic appearance of the removed chondromas.
Discussion
Shoulder CS is a rare report in the literature (<5%) due to its atypical location.[3] However, SC is a condition with well-defined characteristics. The classification
into primary and secondary forms considers cartilaginous body number, shape, and size
or the presence of a pre-existing disease. In shoulders, the secondary form is the
most common, incidentally diagnosed in tests for a previous underlying disease.[5] Although CS is more common in men, we reported two female patients. The monoarticular
characteristic is consistent with the literature. In both cases, CS had an association
with rotator cuff syndrome.
The cartilaginous bodies originating from synovial metaplasia[3] may increase in size and undergo calcification[3]
[4] or endochondral ossification, causing joint erosions, pain, stiffness, and movement
restriction[.3] Therefore, imaging tests are essential, and their findings depend on the stage of
the disease. Our patients underwent shoulder radiography and MRI, which detected loose
bodies. In both cases, the MRI showed rupture of the supraspinatus tendon. Rotator
cuff injury may result from the persistent presence of loose bodies in the subacromial
region and impingement.[6]
Although there is controversy about the best therapy for SC[2]
[7]
[8]
[9] and reports of spontaneous remission,[7] most of the literature supports surgical treatment.[1]
[2]
[9] Most cases under conservative therapies remain symptomatic or present with symptoms
worsening before surgery.[9] Everything indicates that arthroscopic treatment is the gold standard,[9] but the need for synovectomy is not yet well established.[2]
[8]
[9] Disease recurrence has been reported since SC can affect the tendon sheath of the
long head of the biceps and escape detection or due to its incomplete treatment with
an isolated arthroscopic technique by not using arthrotomy or mini-open techniques
when necessary.[9] Several authors described loose bodies removal with synovectomy.[8] However, Jeffreys (1967) concluded that only removing loose bodies was successful.[10] Milgram (1977) apud Maurice et al.[8] (1988) recommended synovectomy with free body removal for the initial SC stage and
the isolated removal of these bodies in the late stage.
Some authors, such as Ramos et al.[7] (1997), prefer the simple removal of articular free bodies. However, when these
bodies are close to the synovium, as in our cases, we propose the addition of arthroscopic
synovectomy to increase procedural precision. Arthroscopy involves small incisions,
allows assessing the entire glenohumeral joint, and facilitates rapid rehabilitation.[1]
[2] We believe that synovectomy and removing all loose bodies is the best therapy for
shoulder CS, and resection of the bursa with the nodules in the subacromial region
can minimize the occurrence of future rotator cuff injuries.[6] There are reports of recurrence when the synovial membrane is not excised,[3] favoring malignant transformation to synovial chondrosarcoma, although this event
is rare.[1]
[3] The association of radiotherapy with treatment is questioned because there is little
benefit in its use since metastasis developed by patients with previous CS is rare.[1]
Rehabilitation with physical therapy is critical for shoulder function recovery and
provides the good outcomes described in the literature.[9] In both cases, there was an improvement in pain and glenohumeral joint mobility.
Long-term outpatient monitoring of these subjects is valuable since we must not neglect
a potential recurrence. We should consider evaluation with imaging tests every 2 or
3 years for SC treatment.[2]
[5]
[8]
