Chondromatosis Research Articles

Arthroscopic Management of Metacarpophalangeal Joint Synovial Chondromatosis

AbstractSynovial chondromatosis is a rare condition where cartilaginous nodules form within the synovium, which can detach and cause loose bodies within the joint. While it typically affects larger joints, involvement of the metacarpophalangeal (MCP) joints is rarely described. We report the case of a 42-year-old female patient who had a slow-growing mass in her right third MCP (MCP III) joint, associated with limited finger motion, swelling, and pain. The diagnosis was confirmed using imaging studies. The patient underwent arthroscopic excision of multiple tumors and synovectomy via dorsal radial and ulnar MCP III portals. Postoperatively, there was rapid improvement in hand function, including normal and pain-free range of motion. This case highlights the benefits of arthroscopic management for synovial chondromatosis in the MCP joint, as it offers advantages like minimal invasiveness, reduced tissue damage, faster recovery times, and lower infection risk compared with traditional open methods.

Comparative analysis of synovectomy and total knee replacement in knee joint synovial chondromatosis: A case series

Synovial chondromatosis is a rare disorder characterized by cartilaginous growths within the joint lining, often confused with conditions like pigmented villonodular synovitis and rheumatoid arthritis. Primary treatment typically involves surgical synovectomy to remove the affected tissue and loose bodies. Documented cases are limited globally. The aim of this study was to present a case series of synovial chondromatosis and evaluate the functional outcomes by assessing the post-surgical Musculoskeletal Tumor Society (MSTS) score following different surgical interventions (synovectomy alone versus synovectomy with total knee replacement) in a resource-limited setting. Four cases of synovial chondromatosis were reported. A 61-year-old woman with a soft tissue tumor underwent synovectomy and total knee replacement on the right knee, then experienced a periprosthetic infection requiring revision arthroplasty, resulting in an MSTS score of 24. Another case was a 48-year-old woman who had a synovectomy for a lump on the right knee, also achieving an MSTS score of 24. Two additional cases involved women in their mid-to-late 60s who underwent synovectomy for knee lumps, with post-operative MSTS scores of 21 and 19, respectively. This case series underscores the diagnostic and management challenges of synovial chondromatosis in the knee joint, demonstrating various surgical interventions. This case series also suggested that the post-operative MSTS scores were slightly higher (indicating better outcomes) for synovectomy alone compared to synovectomy with total knee replacement, highlighting the need for further research to determine the most effective treatment approach.

Decreased volume of rectus femoris and iliocapsularis in patients with femoroacetabular impingement syndrome after primary hip arthroscopy

Purpose(1) to investigate the consecutive changes in hip muscle volume in patients with femoroacetabular impingement syndrome (FAIS) during the initial postoperative period, and (2) to determine the potential effect of the early changes in hip muscle volume on clinical outcomes.MethodsData between March 2021 and March 2022 was reviewed. Patients diagnosed with FAIS based on clinical symptoms and radiographic findings, and undergoing hip arthroscopic treatment were included. Exclusion criteria were incomplete MRI data, prior history of hip surgery, and concomitant hip conditions including hip osteoarthritis with a Tönnis grade > 1, avascular necrosis, Legg-Calvé-Perthes disease, osteoid osteoma, synovial chondromatosis, pigmented villonodular synovitis, and developmental dysplasia of the hip (DDH). MRI was performed preoperatively and 3, 6, 12-month postoperatively. Cross-sectional area (CSA) of hip muscles including rectus femoris (RF), iliocapsularis (IC), iliopsoas (IP), gluteus medius/minimus complex (G-med/min), and gluteus maximus (G-max) were collected on MRI. The CSA was corrected by body surface area (BSA). Preoperative and a minimum of 2-year postoperative patient-reported outcome (PRO) scores including Visual Analog pain Scale (VAS), modified Harris Hip Score (mHHS), and international Hip Outcome Tool, 12-component form (iHOT-12) were collected. A multivariate linear regression model was built to determine the influence of the potential factors on postoperative PROs.ResultsA total of 76 patients were included in the study. Compared to the preoperative level, decreased volume of RF and G-max, and increased IC/RF ratio were observed at postoperative 3 months (all with P < .05). Both G-med/min and G-max presented decreased volume at postoperative 6 months (all with P < .05). G-med/min presented decreased volume (P = .001) at postoperative 12 months. Changes in RF at postoperative 3 months and 12 months were positively related to improvement of iHOT-12 (Beta = 0.371, P = .012 and Beta = 0.330, P = .026, respectively). Changes in IC at postoperative 6-month was positively related to improvement of mHHS (Beta = 0.367, P = .027) and iHOT-12 (Beta = 0.315, P = .044).ConclusionDuring the initial first year following arthroscopic treatment for FAIS, decreased volume of the RF and gluteal muscles was observed. Early changes in volume of RF and IC were positively correlated to the improvement of minimum 2-year PROs.Level of evidenceLevel IV; case series.

Extensive Synovial Chondromatosis of the Temporomandibular Joint Extending to the Cranial Base.

A 42-year-old male presented to the Department of Oral and Maxillofacial Surgery with the chief complaint of pain and stiffness in the right temporomandibular joint (TMJ). The patient's height was 174 cm and his body weight was 65 kg. The patient's occupation was heavy equipment operator. According to the patient, the pain had initiated a week prior to his first visit and was exacerbated during mastication. Evaluation of the range of motion revealed extensive crepitus along the right TMJ. The active and passive range of motion were measured at 45 mm and 42 mm, respectively, indicating adequate mouth-opening capacity. Occlusion was also favorable, and no other clinical symptoms were shown intraorally.

Rare presentation of primary synovial chondrosarcoma arising in the shoulder: a case report.

Synovial chondrosarcoma (CHS) is a rare malignant tumor arising from the synovial tissue and is often associated with synovial chondromatosis. Herein, we present a unique case of primary synovial CHS in the shoulder joint without evidence of synovial chondromatosis. A 60-year-old man presented to our hospital with a complain of left shoulder pain that persisted for 6years, which was initially misdiagnosed as synovitis. Radiography revealed an osteolytic lesion involving the humerus and the scapula. Histologically, the tumor exhibited features of grade 2 synovial CHS, infiltrating the trabecular bones and intra-articular space. Wide resection led to a 9-year recurrence-free survival. This case underscores the challenges in diagnosing and managing synovial CHS, particularly in cases with atypical presentations lacking synovial chondromatosis, necessitating careful follow-up and adequate surgical intervention.

Arthroscopic Chondral Nail Fixation for Treating Acetabular Cartilage Delamination Results in Improved Pain Relief at Minimum 2-year Follow-up in Patients with Femoroacetabular Impingement Syndrome: A Propensity-Matched Study

PurposeTo investigate the clinical outcomes following arthroscopic chondral nail fixation for acetabular cartilage delamination (ACD) in patients with femoroacetabular impingement syndrome (FAIS), and the presentation of ACD on MRI at follow-up. MethodsA retrospective review was performed between March 2021 and March 2022 at our institute. Patients undergoing primary hip arthroscopy for FAIS and diagnosed with ACD intraoperatively were included. Exclusion criteria were incomplete data or loss of minimum 2-year follow-up, and concomitant hip conditions including hip osteoarthritis with a Tönnis grade > 1, avascular necrosis, Legg-Calvé-Perthes disease, osteoid osteoma, synovial chondromatosis, pigmented villonodular synovitis, and developmental dysplasia of the hip (DDH). Patients who underwent chondral nail fixation were matched 1:1 with a control cohort of patients who only underwent simple debridement. Preoperative and minimum 2-year postoperative patient-reported outcome (PRO) scores including Visual Analog pain Scale (VAS), modified Harris Hip Score (mHHS), and percentage of achieving minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) were collected and compared. MRI was performed preoperatively and at final follow-up to assess ACD. ResultsFifty-eight patients were included in the study (29 patients in each group). Both groups demonstrated improved VAS and mHHS following surgery (all with P < .05). The chondral nail group demonstrated better postoperative VAS (P = .022) compared to the control group, while the postoperative mHHS was comparable between the two groups (P = .852). No significant difference was found in the achievement of MCID between the two groups (all with P > .05). More patients in the chondral nail group achieved PASS of VAS compared to the control group (75.9% vs 48.3%, P = .030). No patient underwent revision surgery or conversion to total hip arthroplasty (THA). The chondral nail group demonstrated significantly higher rate of ACD healing on MRI compared to the control group (P < .001). ConclusionPatients undergoing arthroscopic chondral nail fixation for treating ACD demonstrated significant pain relief, more achievement of PASS of VAS, and higher rate of ACD healing on MRI compared to those undergoing simple debridement. Level of EvidenceLevel III; retrospective cohort study.

Synovial chondromatosis : Results from the histopathological arthritis register of the German Society for Orthopedic Rheumatology

Synovial chondromatosis, or osteochondromatosis, is arare benign disorder that occurs in joints, tendon sheaths, or bursae, characterized by cartilage proliferations of varying sizes and shapes, often with ossifications. In this study the prevalence, sensitivity, gender predominance, differential diagnoses, and primary localization of synovial chondromatosis are analyzed within the Histopathological Arthritis Registry of the German Society for Orthopedic Rheumatology. All cases of patients diagnosed with "synovial chondromatosis" from the Histopathological Arthritis Registry of the German Society for Orthopedic Rheumatology were retrospectively examined, covering the period from 1 January 2018, to 31 December 2022. Between 1 January 2018, and 31 December 2022, there were 14cases of synovial chondromatosis out of atotal of 13,222 cases in the Histopathological Arthritis Register of the German Society for Orthopedic Rheumatology. The available data include primary localization, and age and gender of the patients. Among the 13,222 cases in the Histopathological Arthritis Register of the German Society for Orthopedic Rheumatology, 14were histopathologically confirmed as synovial chondromatosis. This resulted in aprevalence of 0.1% or 1.13 per 1,000 cases. The correct clinical presumptive diagnosis was made in 5cases, yielding asensitivity of 35.7%, 95% confidence interval (CI) 12.8% to 64.9%. Differential diagnoses for this condition include pigmented villonodular synovitis, tenosynovial giant cell tumor, and chondrosarcoma. Synovial chondromatosis frequently occurs in large joints such as the knee, hip, and the temporomandibular joint. A peak incidence is described in the fifth decade of life. However, the disorder can also occur in children. For the first time, the study was able to provide data for Germany based on alarge sample. Additionally, initial statements regarding the prevalence and sensitivity of synovial chondromatosis could be made. The aim of this work is to raise awareness of this very rare disease to enable faster and more efficient diagnosis. The study also highlights the importance of histopathology in the diagnosis of synovial chondromatosis.

Non-cutaneous soft tissue tumors and pseudotumors in the foot and ankle reported in Brazilian services

Objectives: Review the histological types of non-cutaneous soft tissue tumors and pseudotumors that affect the foot and ankle,reported in Brazilian health services.Methods: An integrative review of the literature from the Scielo and PubMed platforms, based on the descriptors “Soft Tissue Tumors,”“Pseudotumors,” “Foot, “Ankle,” and “Brazil.” Those who answered the following research question: “What are the non-cutaneous softtissue tumors and pseudotumors in the foot and ankle reported in Brazilian health services?” were included. The combination of eachauthor’s analysis contributed to reducing possible biases.Results: Six articles were selected, yielding 23 reports of tumors and pseudotumors, which were subsequently categorized intomalignant and benign tumors. There were five benign findings: three benign tumors, two giant cell tumors, one fibromatosis, andtwo pseudotumors classified as synovial chondromatosis. Eighteen malignant findings were reported: seven unspecified soft tissuesarcomas, four synovial sarcomas, three myxofibrosarcomas, one fibrosarcoma, one liposarcoma, one undifferentiated pleomorphicsarcoma and one papillary intralymphatic angioendothelioma.Conclusion: In the last ten years, more reports of malignant than benign tumors have been reported. However, this finding does notnecessarily reflect the Brazilian epidemiological reality, as it may represent a view in which resected benign tumors and pseudotumorsare often not sent for anatomopathological study or reported in the literature. Level of evidence I; Prognostic studies - investigating the effect of a patient characteristic on the outcome of disease

Clinical guidance based on MRI for the management of temporomandibular joint synovial chondromatosis: One institution's experience

The aim of this retrospective observational study was to introduce a comprehensive MRI evaluation criterion for the clinical management of synovial chondromatosis of the temporomandibular joint (TMJ-SC). Patients received different treatments according to the MRI evaluation system: bone erosion, extent, articular disc condition, location, maturity, and size of loose body. At least a 2-year follow-up was completed to assess tumor recurrence, visual analogue scale score for pain (VAS) and maximum interincisal opening (MIO). Of the 195 patients included for TMJ-SC, 34 received arthroscopy and 161 received open surgery. Among the patients with significant extent of SC, 32 received temporary resection of the condylar neck or zygomatic arch and 2 received treatment combined with ear, nose and throat(ENT). 28 received articular disc reconstruction and 56 received disc repositioning. Patients showed good recovery of joint function with only two cases of tumor recurrence at an average follow-up of 75.1 months after surgery. The MIO had improved from 30.2 mm to 40.0 mm(P < 0.0001) and VAS had decreased from 5.1 to 0.78(P < 0.0001).The preoperative MRI evaluation principles has been effective in selecting appropriate surgical options.

Osteopoikilia in the practice of a rheumatologist

Osteopoikilia (OPC) is a rare, benign autosomal dominant disease characterized by sclerotic bone lesions, which usually proceeds asymptomatically. It is usually diagnosed by accident with conventional radiography. In most patients, the disease is asymptomatic, but some may complain of mild joint pain and swelling. Differential diagnoses of the disease include osteoblastic metastases, primary bone tumor, mastocytosis, tuberous sclerosis, synovial chondromatosis and melanostasis. In the literature, we have found reports of the coexistence of OPC with rheumatological diseases such as fibromyalgia, reactive arthritis, familial Mediterranean fever, psoriatic arthritis, rheumatoid arthritis, seronegative spondyloarthritis. Thus, the clinical case we observed is interesting not only from the standpoint of the importance of establishing a clinical diagnosis, but also the timeliness of starting treatment, which affects the prognosis of the disease.

Synovial chondromatosis of the shoulder: A rare case report

Synovial chondromatosis is a monarticular svnovial proliferative disease in which cartilaginous or osteocartilaginous metaplasia occurs within the synovial membrane of joints, bursae or tendon sheaths. The disease has been classified into three phases. 1: Early: with svnovial chondrometaplasia but no loose bodies; 2: Transitional: with active svynovial disease and loose bodies; 3: Late: With loose bodies but no synovial disease.Cartilaginous metaplasia from joint, tendo, or bursal synovial lining differentiates this entity from loose bodies arising from degenerative arthritis, osteochondritis dissecans. and osteochondral fractures. A 54 Year Hindu male presented to the orthopaedic OPD with complains of pain and swelling in left shoulder which was insidous in onset, gradually progressive in nature and not relieved by medications. Patient also complained of clicking noise during shoulder movements which was insidous in onset and gradually progressive in nature. Synovial chondromatosis is a synovial lesion seen generally in adults with a male predominance. It occurs most commonly in the knee, unsually also occuring at the hand, wrist, elbow and shoulder. It can lead to mechanical symptoms, decreased range of motion and effusion. Histopath shows nodules of moderately cellular hyaline cartilage. D/D can include Myositis Ossificans, Synovial Chondrosarcoma and Synoval Sarcoma. Treatment is usually observation if asymptomatic. It symptomatic, then arthroscopic or open synovectomy can be done, arthroscopy increases chances of recurrence.

Is Arthroscopic Management of Synovial Chondromatosis of the Hip Enough?

Abstract Study Design: The design of the study was a retrospective case series. Objective: This study evaluated the clinical and radiological manifestations of synovial chondromatosis (SC) of the hip, along with the role of hip arthroscopy in the diagnosis and treatment of this pathologic condition and its postoperative curative effect. Patients and Methods: With a minimum 1-year follow-up, 13 hips with SC received arthroscopic surgery. Preoperatively and postoperatively, patients were assessed for hip pain using the modified Harris Hip Score and Nonarthritic Hip Score. Results: Considerable reduction in postoperative hip pain was observed in all cases, along with sufficient improvement in hip range of motion. Conclusion: Hip arthroscopy is a trusted and adequate treatment option for hip SC.

Longitudinal Assessment of Clinical Outcomes After Arthroscopic Treatment for Hip Synovial Chondromatosis and the Effect of Residual Loose Bodies: Minimum 4-Year and 8-Year Follow-up

Background: Arthroscopic treatment is recommended for hip synovial chondromatosis. However, evidence regarding long-term clinical outcomes is limited. Purpose: To evaluate long-term patient-reported outcomes (PROs) and survival, and to determine the potential effect of residual loose bodies, as evaluated by immediate postoperative computed tomography (CT), on clinical outcomes. Study Design: Case series; Level of evidence, 4. Methods: A consecutive cohort of patients undergoing arthroscopic treatment and diagnosed with synovial chondromatosis between March 2010 and May 2015 were included in the study. Preoperative radiography, CT, and magnetic resonance imaging were performed. Preoperative, midterm (minimum of 4 years), and long-term (minimum of 8 years) PROs were collected for visual analog scale for pain, modified Harris Hip Score (mHHS), Non-Arthritic Hip Score (NAHS), and 12-item international Hip Outcome Tool (iHOT-12). The percentages achieving minimal clinically important difference (MCID) were calculated. PROs and survival were compared between patients with and without residual loose bodies evident on immediate postoperative CT scan. Results: A total of 28 patients (20% of patients were lost to follow-up) were included in the study with a mean follow-up period of 104.9 months (range, 96-139 months). PROs including visual analog scale for pain (preoperative, 3.8 ± 1.2; midterm, 0.9 ± 1.7; long-term, 0.8 ± 1.4), mHHS (preoperative, 66.4 ± 14.4; midterm, 92.8 ± 12.3; long-term, 93.5 ± 10.5), NAHS (preoperative, 45.2 ± 16.2; midterm, 81.8 ± 15.3; long-term, 83.1 ± 12.9), and iHOT-12 (preoperative, 48.4 ± 15.6; midterm, 69.3 ± 11.7; long-term, 72.7 ± 11.4) were improved at both midterm and long-term follow-up (all with P < .001). In total, 27 (96.4%), 28 (100%), and 26 (92.9%) patients achieved MCID for mHHS, NAHS and iHOT-12, respectively, at the long-term follow-up. No significant difference was found in any of the PROs and the rate of achieving MCID between midterm and long-term follow-up (all with P > .05). One patient (3.6%) underwent revision surgery. Among the 23 patients who had loose bodies on preoperative CT or radiographs, 14 patients (60.9%) with residual loose bodies evident on immediate postoperative CT demonstrated lower NAHS (P = .045) and iHOT-12 (P = .037) scores but a comparable survival (P > .05) at long-term follow-up compared with those who did not have loose bodies. Conclusion: Arthroscopic treatment for hip synovial chondromatosis achieved satisfactory long-term clinical outcomes with strong survival. Most patients maintained or improved their overall functional status between midterm and long-term follow-up. Furthermore, patients with residual loose bodies had less favorable clinical outcomes, although the survival rate was comparable.

Pigmented villonodular synovitis of knee with concomitant partial tear of anterior cruciate ligament in skeletally immature patient: A case report

Pigmented villonodular synovitis (PVNS) is benign but locally aggressive proliferative disorder that affects synovial joint, tendon sheaths, and bursae. PVNS is rare in child, while concurrent Anterior Cruciate Ligament (ACL) tear in PVNS is uncommon finding. Previous study reported ACL tear might be a risk factor in adult PVNS but lack of record for pediatric PVNS. We report a case of uncommon concomitant ACL partial tear in an already rare pediatric PVNS. A nine-year old female with pain and swelling on left knee, occurred intermittent every 2 months for 1 year prior to surgery. There was moderate knee movement restriction with history of fall from bicycle 1 year before surgery. No history of knee instability was reported. X-ray only denote joint swelling, while MRI shows intraarticular bodies suspected synovial chondromatosis with hyperintense signal sign of partial ACL tear. The patient underwent arthroscopic evaluation which exhibit intraarticular hyperemic and hypertrophic synovium with loosening anteromedial ACL bundle. Arthroscopic synovectomy was then performed followed by range of motion training and muscle strengthening rehabilitation program. Post-operative histopathological result confirms PVNS assessment. 1 year follow up post-surgery shows no recurrence of pain or swelling with free movement of left knee joint and no disturbance or instability while walking. In this case, partial ACL tear may contribute as risk factor of PVNS in child. Arthroscopic synovectomy with physical rehabilitation program shows good functional result with no recurrence at 1-year follow up.

Management of Synovial Chondromatosis of the Elbow With Ulnar Nerve Palsy by Open Approach: A Case Report

Management of Synovial Chondromatosis of the Elbow With Ulnar Nerve Palsy by Open Approach: A Case Report

Synovial Chondromatosis of Right Knee: A Case Report

Abstract Synovial chondromatosis is a rare cartilaginous neoplasm that most commonly affects the knee joint. Histologically, it presents as a multinodular cartilaginous proliferation showing clusters of chondrocytes. These can be quite atypical, simulating chondrosarcoma. The lesion is usually self-limited but sometimes may exhibit a more aggressive clinical course characterized by multiple local recurrences. Chondrosarcomatous transformation in synovial chondromatosis is exceedingly rare but has been documented. Until recently, synovial chondromatosis was considered a reactive process. Recent cytogenetic studies have shown recurrent chromosomal abnormalities, especially involving chromosome6, therefore supporting a clonal, neoplastic nature of this intriguing lesion.

CD34+ synovial fibroblasts exhibit high osteogenic potential in synovial chondromatosis.

Synovial chondromatosis (SC) is a disorder of the synovium characterized by the formation of osteochondral nodules within the synovium. This study aimed to identify the abnormally differentiated progenitor cells and possible pathogenic signaling pathways. Loose bodies and synovium were obtained from patients with SC during knee arthroplasty. Single-cell RNA sequencing was used to identify cell subsets and their gene signatures in SC synovium. Cells derived from osteoarthritis (OA) synovium were used as controls. Multi-differentiation and colony-forming assays were used to identify progenitor cells. The roles of transcription factors and signaling pathways were investigated through computational analysis and experimental verification. We identified an increased proportion of CD34+ sublining fibroblasts in SC synovium. CD34+CD31- cells and CD34-CD31- cells were sorted from SC synovium. Compared with CD34- cells, CD34+ cells had larger alkaline phosphatase (ALP)-stained area and calcified area after osteogenic induction. In addition, CD34+ cells exhibited a stronger tube formation ability than CD34- cells. Our bioinformatic analysis suggested the expression of TWIST1, a negative regulator of osteogenesis, in CD34- sublining fibroblasts and was regulated by the TGF-β signaling pathway. The experiment showed that CD34+ cells acquired the TWIST1 expression during culture and the combination of TGF-β1 and harmine, an inhibitor of Twist1, could further stimulate the osteogenesis of CD34+ cells. Overall, CD34+ synovial fibroblasts in SC synovium have multiple differentiation potentials, especially osteogenic differentiation potential, and might be responsible for the pathogenesis of SC.

A Case of Baker’s Cyst with Synovial Chondromatosis of Knee

Synovial chondromatosis is a benign condition which arises from synovial membrane or bursae around the joints. Joint abnormalities in the form of arthritic or mechanical conditions such as detachment of osseocartilaginous fragments from the articular surface are its secondary associations. Rarely there maybe involvement of the Baker’s cyst. Here we report a case in which a 60-year-old female came with complaints of pain, swelling and restriction of movement of right knee joint for the past one year. After careful clinical and radiological examination, it was diagnosed as Baker’s cyst complicated by synovial chondromatosis. After the diagnosis the patient underwent the following procedures: open synovectomy, cyst removal and thorough joint debridement. Synovial chondromatosis was confirmed histopathologically. Secondary synovial chondromatosis has features of osteoarthritic changes, lack of extensive synovial proliferation and complicated Baker's cyst which is not seen in primary synovial chondromatosis.&#x0D; Synovial chondromatosis (SC) is caused by metaplasia of the synovium into chondrocytes and is a rare benign disorder.[1,2] Primary synovial chondromatosis (PSC) is a self-limited process that occurs in an otherwise normal joint.[3] When synovial chondromatosis develops in a joint previously affected with disease, often posttraumatic or degenerative osteoarthritis, it is called as secondary synovial chondromatosis.[4] SC may involve any joint, but the most common joint involved is knee joint followed by hip joint, and small joints of the hand and wrist. Least involvement is seen in elbow and shoulder joint. [5] The disease is categorised into three phases according to Milligram classification: active intrasynovial disease without any loose bodies observed in the early phase, active disease and loose bodies observed in the transitional phase, and multiple loose bodies without any intrasynovial disease observed in the late phase.&#x0D; In orthopaedic practice, popliteal cysts are common occurrence; many of them are associated with degenerative or rheumatoid arthritis. The differential diagnoses become more complex when loose bodies and calcifications are noted within the joint on a radiograph. Here in, we are presenting a case of Baker’s cyst with synovial chondromatosis of knee treated by surgical excision and confirmed by histopathology.

АРТРОСКОПИЧЕСКАЯ ХОЛОДНО-ПЛАЗМЕННАЯ АБЛЯЦИЯ ПРИ РЕДКИХ ЗАБОЛЕВАНИЯХ СИНОВИАЛЬНОЙ ОБОЛОЧКИ КОЛЕННОГО СУСТАВА. КЛИНИЧЕСКИЕ НАБЛЮДЕНИЯ

Background. Over a long period, an open capsular synovectomy technique was recommended for villous nodular synovitis and synovial chondromatosis of the knee joint. However, such surgical treatment is accompanied by significant trauma to the joint tissue and frequent postoperative recurrence. Currently, it is advisable to assess the possibilities of modern treatment methods (arthroscopic cold plasma ablation) for rare diseases of the knee joint. The aim of the study. To assess the possibilities of arthroscopic cold plasma ablation in a series of clinical observa-tions of the surgical treatment of patients with rare diseases of the knee joint synovium in a statistically small sample. Material and methods. Surgical treatment was performed in 14 patients with diseases of the knee joint synovium. We carried out clinical and radiological examinations, computed tomography and magnetic resonance imaging, multi-detector computed tomographic angiography, ultrasound examination, Dopplerography of the vessels of the lower extremities, biochemical examination of synovial fluid, arthroscopy with targeted biopsy and subsequent morphological examination of the synovial membrane. Results. In 7 patients with pigmented villous nodular synovitis, the following surgeries were performed: in 1 patient with the diffuse form – an open subtotal capsular sinovectomy; in 6 patients with the nodular form – an arthroscopic partial cold plasma capsular sinovectomy of the knee joint. In 7 patients with synovial chondromatosis, an arthroscopic removal of cartilage flaps and partial cold plasma ablation of synovial folds and knee joint villi were carried out. Conclusion. Arthroscopic cold plasma ablation with bipolar electrodes in various modes of the Qvantum-2 (Arthro-Care, USA) using anterior, posterolateral and suprapatellar approaches makes it possible to carry out less traumatic and radical, without damaging deep layers of cartilage and capsule, surgical treatment of rare diseases of the knee joint synovium. In diffuse forms of pigmented villous nodular synovitis, it is advisable to continue comparative studies of various surgical methods of capsular sinovectomy (open and arthroscopic techniques).

Crystal induced arthropathies-a comparative study of 40 patients with apatite rheumatism, chondrocalcinosis and primary synovial chondromatosis.

Introduction: Apatite rheumatism (AR), chondrocalcinosis (Ch-C), and primary synovial chondromatosis (prSynCh) are regarded as distinct clinical entities. The introduction of the non-staining technique by Bély and Apáthy (2013) opened a new era in the microscopic diagnosis of crystal induced diseases, allowing the analysis of MSU (monosodium urate monohydrate) HA (calcium hydroxyapatite), CPPD (calcium pyrophosphate dihydrate) crystals, cholesterol, crystalline liquid lipid droplets, and other crystals in unstained sections of conventionally proceeded (aqueous formaldehyde fixed, paraffin-embedded) tissue samples. The aim of this study was to describe the characteristic histology of crystal deposits in AR, Ch-C, and prSynCh with traditional stains and histochemical reactions comparing with unstained tissue sections according to Bély and Apáthy (2013). Patients and methods: Tissue samples of 4 with apatite rheumatism (Milwaukee syndrome), 16 with chondrocalcinosis, and 20 with clinically diagnosed primary synovial chondromatosis were analyzed. Results and conclusion: Apatite rheumatism, chondrocalcinosis, and primary synovial chondromatosis are related metabolic disorders with HA and CPPD depositions. The authors assume that AR and Ch-C are different stages of the same metabolic disorder, which differ from prSynCh in amorphous mineral production, furthermore in the production of chondroid, osteoid and/or bone. prSynCh is a defective variant of HA and CPPD induced metabolic disorders with reduced mineralization capabilities, where the deficient mineralization is replaced by chondroid and/or bone formation. The non-staining technique of Bély and Apáthy proved to be a much more effective method for the demonstration of crystals in metabolic diseases than conventional stains and histochemical reactions.