An evidence-based etiology study of synovial cyst of knee cruciate ligament: a real or pseudo-cyst.

PURPOSE: Synovial cyst of knee cruciate ligament (SCKCL) is a rare condition but can cause severe knee pain. The understanding of its etiology is relatively poor. This current study aimed to elucidate the pathogenesis of SCKCL based on a series of histo- and cytopathological examination. METHODS: Ten SCKCL patients who underwent arthroscopy were enrolled, among five patients claimed past knee injury. Hematoxylin & eosin staining was conducted to the cyst wall tissue sections and Papanicolaou staining to the cyst fluid smear. Prussian blue staining was employed to both the wall section and fluid smear. Immumohistochemical staining for mesothelial cells (MC), epithelial cells (CK), vascular endothelial cells (CD31), monocytes (CD68), and hematogenous stem cells (CD117) were taken to elucidate the possible involvement of various cell types in the development of SCKCL. RESULTS: No erythrocyte was discovered in the fluid; however, Prussian blue stained hemosiderin particles were found in the cyst wall and fluid, suggesting past hemorrhage in all patients. Abundant lymphocytes and plasmocytes were observed in the cyst wall and fluid. In addition, the cyst lining was infiltrated with abundant CD68(+) monocytes while only few MC(+) mesothelial cells were sporadically observed in four samples. The cyst submucosa was also diffused with abundant CD68(+) monocytes and proliferated capillaries stained with CD31. CD117-positve hematogenous stem cells were sporadically observed in eight specimens. CONCLUSION: Our findings provided evidence that SCKCL is not a mature synovial cyst but rather an inflammatory pseudo-cyst. It may have resulted from past minor hemorrhage and intra-ligament chronic inflammation.

Musculosceletal tuberculosis with involvement of tendon sheaths and formation of synovial cyst.

Due to an increasing amount of patients on immunosuppressive treatment, the number of tuberculosis (TB) of atypical course and extrapulmonary tuberculosis cases increase. Locomotor system is a place of every fifth case of extrapulmonary TB. Because of lack of characteristic symptoms, as well as rare co-occurrence of active lung lesions in radiological imaging, proper diagnosis is hard to establish. We present a case of patient on immunosuppressive therapy due to myositis, in whom we diagnosed musculoskeletal tuberculosis in form of involvement of tendon sheath and formation of synovial cyst.

Lumbar Synovial Cysts-Should You Fuse or Not?

BACKGROUND: Spinal synovial cysts are lesions that most commonly occur in the lumbar region. The need for an instrumented spinal fusion in addition to lumbar decompression with removal of the synovial cyst is unknown. OBJECTIVE: To test the hypothesis that select patients who underwent decompression with instrumented fusion for lumbar synovial cysts would be less likely to have subsequent surgery (SS) in a 2-year period than patients treated with laminectomy alone. METHODS: This retrospective cohort study was performed using IBM MarketScan Commercial Claims and Encounters Database. Patients who had a lumbar synovial cyst diagnosis and laminectomy surgery with or without fusion surgery were included in this study. Patients were tracked for SS 2 years after surgery. Laminectomy patients were propensity score-matched to laminectomy with fusion (LF) patients using a 2:1 ratio. The log-rank test and Cox regression were used to compare the cumulative incidence of SS between groups. RESULTS: There were 7664 and 1631 patients treated with laminectomy and LF before matching. After matching, there were 2212 laminectomy and 1631 LF patients and patient characteristics were balanced. The 2-year incidence of recurrent SS was 3.1% ([CI]: 2.2%, 4.0%) and 1.7% (95% CI: 0.9%, 2.5%) laminectomy and LF, respectively. Compared with laminectomy, LF had a statistically significant lower risk of recurrent SS (hazard ratio: 0.56 [95% CI: 0.32-0.97]; P -value: .04). CONCLUSION: All patients who had concomitant lumbar fusion showed decreased chance of having a cyst- or noncyst-related recurrence SS when compared with all patients undergoing laminectomy alone, regardless of diagnosis at the time of SS.

Creation and validation of a predictive model for lumbar synovial cyst recurrence following decompression without fusion.

OBJECTIVE: Lumbar synovial cysts (LSCs) represent a relatively rare clinical pathology that may result in radiculopathy or neurogenic claudication. Because of the potential for recurrence of these cysts, some authors advocate for segmental fusion, as opposed to decompression alone, as a way to eliminate the risk for recurrence. The objective of this study was to create a predictive score for synovial cyst recurrence following decompression without fusion. METHODS: A retrospective chart review was completed of all patients evaluated at a single center over 20 years who were found to have symptomatic LSCs requiring intervention. Only patients undergoing decompression without fusion were included in the analysis. Following this review, baseline characteristics were obtained as well as radiological information. A machine learning method (risk-calibrated supersparse linear integer model) was then used to create a risk stratification score to identify patients at high risk for symptomatic cyst recurrence requiring repeat surgical intervention. Following the creation of this model, a fivefold cross-validation was completed. RESULTS: In total, 89 patients were identified who had complete radiological information. Of these 89 patients, 11 developed cyst recurrence requiring reoperation. The Lumbar Synovial Cyst Score was then created with an area under the curve of 0.83 and calibration error of 11.0%. Factors predictive of recurrence were found to include facet inclination angle > 45°, canal stenosis > 50%, T2 joint space hyperintensity, and presence of grade I spondylolisthesis. The probability of cyst recurrence ranged from < 5% for a score of 2 or less to > 88% for a score of 7. CONCLUSIONS: The Lumbar Synovial Cyst Score model is a quick and accurate tool to assist in clinical decision-making in the treatment of LSCs.

Is the etiology of pretibial cyst formation after absorbable interference screw use related to a foreign body reaction?

BACKGROUND: Arthroscopically assisted anterior cruciate ligament reconstruction using a bioabsorbable tibial fixation screw is occasionally complicated by pretibial cyst formation. The few case reports describing pretibial cyst formation noted several graft types and fixation techniques, making it difficult to establish one etiology. Some literature suggests cysts form from communication between the joint and pretibial area leading to extravasation of joint fluid, maturing into a cyst. We propose the development of cysts after PLLA screw use may be related to a foreign body reaction. QUESTIONS/PURPOSES: We propose this foreign body reaction (1) relates to the biochemical breakdown of bioabsorbable materials; and (2) differs from cystic formations resulting from joint communication. METHODS: We retrospectively reviewed seven patients who developed pretibial cysts at least 2 years after original primary ACL reconstruction surgery. MRI was used to visualize the extent of cystic formation. Cysts were treated by débridement with specimens sent for histologic analysis. Cyst appearance had a 3-year incidence of 5%. RESULTS: No cyst had an infectious etiology. In all cases, the tibial screw outline was present on MRI, although intraoperatively, the screw was substantially decomposed. Grafts were well incorporated and none of the knees demonstrated anterior laxity. Histologically, cyst material contained fragments of PLLA surrounded by foamy histiocytes, suggesting a foreign body reaction. No cysts recurred. CONCLUSIONS: Tibial cysts occur in a subset of patients undergoing ACL reconstruction using a bioabsorbable PLLA interference screw. We suspect they arise from a foreign body response to the screw breakdown. Removal is well tolerated. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

An anatomically based imaging sign to detect adventitial cyst derived from the superior tibiofibular joint.

The origin for complex intraneural cysts remains controversial despite recent emerging evidence to support their articular origin. The coexistence of intraneural and adventitial cysts has been described due to the proximate neurovascular bundle, i.e., the articular (neural) branch and vessels at the joint capsule. To clarify the pathogenesis, anatomically based imaging patterns can be identified. This paper characterizes a common finding identified on MRI describing the adventitial component originating from the superior tibiofibular joint (STFJ). MRIs of patients with fibular (peroneal) (n = 24) and tibial (n = 7) intraneural ganglion cysts were reviewed. Eleven patients with fibular intraneural ganglion cysts were identified as having a coexisting adventitial component. In all cases, the adventitial cyst extended from the anterior portion of the STFJ, within the capsular vessels, and along the anterior tibial vessels. The reproducible anatomy permitted the identification of an imaging pattern: the "vascular U" sign, consisting of cystic anterior tibial vessels running through the interosseous membrane between the proximal tibia and fibula. This sign was seen on axial MR image(s) obtained at the level of the fibular neck in all cases. To generalize these findings, the rare tibial intraneural ganglion cysts (derived from the posterior aspect of the STFJ) were examined; two cases had coexisting adventitial cysts with visualization of the vascular U sign. This new imaging pattern can improve the identification of adventitial cysts at the level of the STFJ.

Bicipital synovial cyst as the sole musculoskeletal presentation of systemic juvenile idiopathic arthritis-case report.

To describe a unique presentation of fever and bilateral bicipital synovial cysts in young female with systemic juvenile idiopathic arthritis (SJIA). A previous healthy 5-year-old female presented with spiking fever and sudden painless bilateral swelling on the flexor aspect of the upper arm. Ultrasonography confirmed a cystic structure with multiple septae, thickening and tenosynovitis of bicipital tendon but without Doppler signals inside or shoulder synovitis, enlightens the term of non-articular synovitis. Thorough analysis of clinical manifestations, disease assessment measures, laboratory findings and imaging of arm swellings eventually disclosed unusual case of SJIA. Systemic juvenile idiopathic arthritis should be considered in case of spiking fever with bicipital synovial cysts. Ultrasound is a useful diagnostic tool in this condition.

Large post-traumatic subarticular cystic lesion following avulsion injury of PCL mimicking tumour.

We describe a patient with a large subarticular cystic lesion in the proximal tibia developed following traumatic avulsion of PCL. There was a demonstrable communication between the cyst and the joint cavity and ingrowth of the synovial tissue was the most probable pathogenetic mechanism for the development of the cyst. We recommend that the post-traumatic cyst must be kept as a differential diagnosis in a patient presenting with cystic lesion around a joint, especially if there is a history of significant trauma in recent past.

Lumbar Juxtafacet Cysts.

AIM: To evaluate the factors affecting the clinical and radiological findings of juxtafacet cyst patients. MATERIAL AND METHODS: Between January 2011 and December 2018, eight patients diagnosed with juxtafacet cyst were reviewed, retrospectively. Patient demographics; signs and symptoms; and neurological examination, radiological, and surgical findings were noted. RESULTS: The mean age was 54 years (range, 34â€"69 years) with five (62.5%) females and three (37.5%) males. There were nine juxtafacet cysts in eight patients. Five cysts (55.5%) were located at the L3â€"L4 level, two cysts (22.2%) at the L4â€"L5 level, and two cysts (22.2%) at the L5â€"S1 level. In all patients with L3â€"L4 cysts, the intercrest line was intersecting the spinal column at L4 vertebral body level. The most frequent symptoms were back pain and radiculopathy. Magnetic resonance imaging and computerized tomography revealed degenerative facet arthropathy in six patients (75%). Three patients (37.5%) had a medical history of trauma. One patient (12.5%) was treated conservatively. Seven patients (87.5%) were advised to undergo surgical treatment. CONCLUSION: Degeneration and instability are the main causes of juxtafacet cysts. They are mainly seen at the L4â€"L5 level due to higher movement capacity of this level. But, if the intercrest line intersects the spinal column at higher levels, degeneration and instability risks move to upper levels, and juxtafacet cysts may occur at the L3â€"L4 or upper levels.

Knee joint synovial cyst following total knee arthroplasty with bone allograft.

Allograft has been shown to be highly successful for managing large osseous defects in total knee arthroplasty. We report a 68-year-old woman in whom a bone allograft had been used during total knee arthroplasty owing to a massive segmental medial tibia plateau defect 4 years earlier. Eighteen months after surgery, a 10x10 cm knee synovial cyst was detected by computed tomography scanning on the anteromedial side of the tibial plateau, and an en-bloc surgical excision was performed. At 36-month follow-up, a 16x12 cm cyst was found. Excision was again performed with removal of the allograft and application of an autologous iliac graft. After allograft removal, clinically and radiologically satisfactory results were achieved at the final follow-up.

Non-popliteal synovial rupture.

The ruptured popliteal synovial cyst is a common complication of chronic knee arthritis. In contrast, non-popliteal synovial rupture is less well recognized and may present a diagnostic dilemma. We report an 81-year-old woman who presented with chest wall pain and ecchymosis. Ultrasonography of the shoulder region readily diagnosed a dissecting parasynovial cyst. She developed the unusual complication of contralateral recurrence. Literature review revealed a small but important set of non-popliteal synovial ruptures in the regions of the shoulder, elbow, wrist, spine, hip, knee, and ankle. Local swelling, inflammation, ecchymosis, and nerve impingement may mimic other conditions. Awareness of the clinical presentations and a high index of suspicion are required to avoid diagnostic confusion. Management data are limited to case reports of arthrocentesis, injection, and very rarely, surgery.

Pseudotumours associated with metal-on-metal hip resurfacing: 10-year Newcastle experience.

We report the incidence of pseudotumours in a single-surgeon consecutive series of 670 metal-on-metal hip resurfacings performed in the last ten years, with a minimum follow-up of one year. Two cases of pseudotumours have been found and are discussed in detail including metrology and wear analyses of the explanted components. The first was a painless, large synovial cyst in the thigh, secondary to aseptic femoral cup loosening 8 years following hip resurfacing. The second was a painful collection of wear debris in the psoas region at one year post surgery caused by impingement, resulting in eccentric edge wearing. In the first case it was decided to retain the bearing surface; in the second case, conversion to a metal-on-polyethylene hip replacement was performed. In our experience the risk of pseudotumours is low (0.15%) and can be fully explained. In selected cases the bearing surface can be retained.

Bilateral brachial synovial cysts in systemic juvenile idiopathic arthritis: Case report and literature review.

AIM: To review the clinical features of brachial synovial cyst. METHOD: A case of bilateral brachial synovial cysts is described in a child suffering from systemic juvenile idiopathic arthritis during a relapse. Magnetic resonance imaging and ultrasonography were conducted to further evaluate the nature of the cysts. The case is compared with known cases in a literature review. RESULTS: Review of the literature showed that brachial synovial cysts occur most commonly in systemic juvenile idiopathic arthritis. It is considered that uncontrolled systemic inflammation and recurrent disease activity might be the cause of synovial cysts. CONCLUSION: Brachial synovial cyst is a rare manifestation of juvenile idiopathic arthritis. Uncontrolled systemic inflammation inducing chronic damage to joint structure may be the primary cause of synovial cyst formation.

Spinal synovial cysts: pathogenesis, diagnosis and surgical treatment in a series of seven cases and literature review.

This study is designed based on the retrospective analysis of patients treated in the Neurosurgical Department of two major hospitals and review of the literature. The aim of this study is to evaluate the efficacy of surgery and address controversial issues in the treatment of symptomatic lumbar intraspinal synovial cysts. Spinal juxtafacet cysts (synovial and ganglion cysts) are a rare cause of low back and radicular leg pain. Although the relevant reports in the international literature are increasing, the controversy about conservative versus surgical treatment and the need for concomitant fusion still exists. Data from seven patients (age range 58-69 years, mean age 61 years) with low back and radicular leg pain due to a lumbar facet joint cyst were retrospectively analyzed. Demographic data, cyst level, presence of concomitant local pathology, treatment and results of treatment were recorded. A follow-up of at least 6 months (range 6-48 months) was conducted and results were noted. All patients had back pain, while five also experienced unilateral radicular leg pain and one had bilateral leg pain. One patient had neurogenic claudication. MRI identified the cyst and highlighted underlying pathology in all cases. All patients underwent surgical cyst excision. No fusion was performed. Post-operatively, all patients showed a total resolution of symptoms with sustained benefit at final evaluation. Review of the literature revealed a trend towards surgery, as this is correlated to a more favorable outcome compared with conservative treatment. Fusion should be performed on a case-by-case basis only. Surgery is a safe and effective treatment choice in this increasingly appearing ailment. A prospective, randomized trial should clarify issues under debate.

Extensor tendon sheath fistula formation as a complication of wrist arthroscopy.

The indications and applications for wrist arthroscopy continue to expand as new techniques and instrumentation evolve. Wrist arthroscopy is now the gold standard investigation for chronic wrist pain before definitive surgery. Although complications are uncommon, they may include infection, neuroma formation, tendon injury, dorsal skin slough, tourniquet neurapraxia, and reflex sympathetic dystrophy. We describe extensor tendon sheath fistula formation arising from the 3/4 portal after diagnostic wrist arthroscopy and our management in this novel case. The formation of a patent communication between the radiocarpal joint and the tendon sheath permitting the collection of synovial fluid has not previously been described.

Multiple extra-articular synovial cysts accompanied by rheumatoid arthritis in the bilateral elbow joints: A case report.

RATIONALE: Synovial cysts are well known in rheumatoid arthritis (RA), and most common in the popliteal fossa. They may produce lots of local symptoms and complaints, which may present initially as an unrelated clinical condition. Few studies have reported multiple extra-articular synovial cysts (MESCs) in the RA patients. Early diagnosis is crucial for patient treatment. PATIENT CONCERNS: A 50-year-old man without any special clinical histories found a soya bean size bump at the left elbow medially, then multiple lumps were found at bilateral elbows and gradually increasing. No pain, no activity, no redness, and swelling. Magnetic resonance imaging (MRI) showed multiple cystic lesions in the bursa and surrounding soft tissue of bilateral elbow joints. In addition, the elbow joint bursa was swollen and the synovial membrane was significantly thickened. DIAGNOSES: The man was diagnosed as RA with multiple extra-articular synovial cysts formation. INTERVENTIONS: The patient was performed tylectomy of the right elbow. Other lumps were punctured and injected with compound betamethasone injection. OUTCOMES: The bumps were reduced in size and the swelling relieved, and the patient was sent to the department of rheumatology and immunology for further treatment. LESSONS: In this case, it is difficult for the diagnosis of RA because of no relative histories and simultaneously multiple cystic lesions in multiple joints. Imaging examinations can show the characteristics of such kind of disease and be very helpful for the diagnosis and differentiate diagnosis.

Anterior cruciate ligament fixation devices: Expected imaging appearance and common complications.

Anterior cruciate ligament reconstruction is a commonly performed orthopaedic procedure which has increased in frequency over the past decade. There are a variety of fixation devices used to secure grafts within the femoral and tibial tunnels during the reconstruction procedure. An understanding of the expected appearance of the varied hardware utilized for reconstruction graft fixation, and their potential complications is important in the review of post-operative imaging. We describe the most common anterior cruciate ligament reconstruction fixation devices and illustrate their more frequently documented abnormalities.

Coflex interspinous implant placement leading to synovial cyst development: case report.

Interspinous process devices (IPDs) have been developed as less-invasive alternatives to spinal fusion with the goal of decompressing the spinal canal and preserving segmental motion. IPD implantation is proposed to treat symptoms of lumbar spinal stenosis that improve during flexion. Recent indications of IPD include lumbar facet joint syndrome, which is seen in patients with mainly low-back pain. Long-term outcomes in this subset of patients are largely unknown. The authors present a previously unreported complication of coflex (IPD) placement: the development of a large compressive lumbar synovial cyst. A 64-year-old woman underwent IPD implantation (coflex) at L4-5 at an outside hospital for low-back pain that occasionally radiates to the right leg. Postoperatively, her back and right leg pain persisted and worsened. MRI was repeated and showed a new, large synovial cyst at the previously treated level, severely compressing the patient's cauda equina. Four months later, she underwent removal of the interspinous process implant, bilateral laminectomy, facetectomy, synovial cyst resection, interbody fusion, and stabilization. At the 3-month follow-up, she reported significant back pain improvement with some residual leg pain. This case suggests that facet arthrosis may not be an appropriate indication for placement of coflex.

A mutilating arthropathy, "rhupus hands" associated with multiple synovial cysts in a patient with systemic lupus erythematosus.

"Rhupus hands" is a phrase coined to describe one of the deforming arthropathies associated with systemic lupus erythematosus (SLE), because the clinical features are indistinguishable from those of rheumatoid arthritis. Herein, we report a case of rhupus hands with multiple synovial cysts arising in a 60-year-old woman with SLE.

Treatment for Periprosthetic Cyst after Total Hip Arthroplasty: Analysis of Six Cases.

The present study investigates the pathogenesis of periprosthetic cysts after total hip replacement, and explores appropriate treatment appoaches. Six patients with periprosthetic cysts after total hip arthroplasty were treated at the First Affiliated Hospital of Nanjing Medical University between 2009 and 2014. During surgery, it was found that all cysts communicated with the hip and the hip prosthesis could be seen after cyst excision. Four patients simply underwent cyst excision, and light red liquid was found in the cyst. Among them, radiological examination revealed that a part of the hip prosthesis projected from the bone bed in one case. Postoperative pathology revealed a synovial cyst with inflammatory cell infiltration. Prostheses were loosened in two cases, so cystectomy and revision of the prosthesis were performed at the same time. Among the six patients, polyethylene wear particles could be seen in five patients through a pathological polarizing microscope. Out of the four patients who underwent simple cyst excision, two patients experienced cyst recurrence within 1 year after surgery; however, there was no cyst recurrence in the two patients who underwent cyst excision and revision of the prosthesis. The formation of a periprosthetic cyst after hip replacement is likely to be related to polyethylene wear and undesirable prosthesis position; in addition, when treated by simple cyst excision, the rate of recurrence was higher.