Analysis of the efficacy of triple-channel minimally invasive knee arthroscopy in treating popliteal cysts in children.

BACKGROUND: This study aimed to investigate a technique for treating pediatric popliteal cysts with a triple-channel knee arthroscopic approach, hypothesizing that this technique exhibits favorable clinical outcomes with reduced recurrence rates. METHODS: A retrospective analysis was conducted on the clinical data of 14 patients with symptomatic pediatric popliteal cysts admitted to the joint surgery center using an arthroscopic minimally invasive technique from December 2017 to December 2020. Arthroscopy was employed for adequate enlargement of the posterior medial flap opening between the cyst and the joint cavity and to completely resect the cyst wall. The popliteal cyst recurrence was assessed through Magnetic Resonance Imaging(MRI) at 3 and 12 months post-surgery, and the Rauschning and Lindgren scores were recorded to evaluate the clinical prognosis. RESULTS: A total of 14 children completed the follow-up, including 8 boys and 6 girls, with a mean age of 9.9 ± 1.1 years (5-12 years); 5 cases in the left knee and 9 cases in the right knee; the mean operative time was 19.2 ± 2.7 min (10-25 min); and the mean follow-up time was 15.1 ± 2.4 months (12-24 months). There was no intraoperative vascular or nerve injury and no incisional exudate infection. Postoperatively, posterior knee symptoms disappeared in the children, Rauschning and Lindgren scores significantly improved, and no recurrence signs were observed on MRI. CONCLUSIONS: This study determined that the arthroscopic three-channel minimally invasive technique is effective and safe for treating popliteal cysts in children, making it worthy of clinical promotion.

Systematic review and meta-analysis of studies comparing cyst wall preservation against cyst wall resection during arthroscopic popliteal cyst decompression.

INTRODUCTION: The optimal arthroscopic management for popliteal cyst decompression remains uncertain, with ongoing debate between preserving the cyst wall or completely removing it. The purpose of this study is to compare the outcomes and complications of arthroscopic popliteal cyst decompression with cyst wall preservation and cyst wall resection. METHODS: A systematic review adhering to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines was conducted. It encompassed studies that focused on arthroscopic popliteal cyst decompression, considering both cyst wall preservation and cyst wall resection. The quality assessment of the included studies was carried out using the Methodology Index for Non-Randomized Research criteria. Following this, meta-analyses were conducted, employing odds ratios (ORs) for dichotomous outcomes and calculating mean differences (MDs) for continuous outcomes. RESULTS: Four articles included a collective of 214 knees. Each of these studies presented level 3 evidence. The comparison between the cyst wall preservation group and the cyst wall resection group revealed similar clinical outcomes based on the Rauschning and Lindgren grade (grade 0 [OR = 0.66, 95% CI: 0.37-1.19, p = 0.17]; grade I [OR = 1.33, 95% CI: 0.66-2.67, p = 0.43]; grade II [OR = 1.39, 95% CI: 0.46-4.14, p = 0.56]; grade III [OR = 3.46, 95% CI: 0.13-89.95, p = 0.46]) and Lysholm score (MD = 0.83, 95% CI: -0.65-2.32, p = 0.27). However, MRI results indicated a significant improvement in the cyst wall resection group (cyst disappearance [OR = 0.50, 95% CI: 0.28-0.90, p = 0.02]; cyst shrinkage or decrease in size [OR = 1.41, 95% CI: 0.78-2.55, p = 0.26]; cyst persistence or recurrence [OR = 7.63, 95% CI: 1.29-45.08, p = 0.02]). Nevertheless, the operative time for cyst resection was significantly longer compared to cyst preservation (MD = -14.90, 95% CI: -21.96 - -7.84, p < 0.0001), and the cyst wall resection group experienced significantly higher complications than the cyst wall preservation group (OR = 0.24, 95% CI: 0.06 to 1.02, p = 0.05). CONCLUSION: During arthroscopic popliteal cyst decompression, cyst wall resection led to longer operative times and higher complication rates but lower recurrence rates and better MRI outcomes. The functional outcomes after surgery were found to be similar.

Cystic lesions and bursae around the knee: do they matter in knee osteoarthritis?

The cause of knee osteoarthritis (OA) and knee pain associated with OA is not well understood. Periarticular cystic lesions and bursae around the knee are among the most common morphologic features identified on MRI in the setting of OA. Despite widespread association of these lesions with knee OA and their inclusion in semiquantitative MRI scoring assessment systems for knee OA, the role that these lesions play in the development of knee pain and OA remains uncertain. In this discussion, we review the cystic lesions and bursae most commonly associated with OA of the knee, examine their relation and role in whole organ imaging assessments of OA, and present the literature investigating the associations of periarticular cysts and cyst-like lesions with knee pain and OA.

Arthroscopic cystectomy and valve excision of popliteal cysts complemented with management of intra-articular pathologies: a low recurrence rate and good functional outcomes in a series of ninety seven cases.

PURPOSE: Arthroscopy in popliteal cyst surgery enables addressing all components of its pathomechanism: the cyst wall, valvular mechanism, and concomitant intra-articular pathologies. Techniques differ as to the management of the cyst wall and the valvular mechanism. This study aimed to assess the recurrence rate and functional outcomes of a cyst wall and valve excising arthroscopic technique with concurrent intra-articular pathology management. The secondary purpose was to assess cyst and valve morphology and concomitant intra-articular findings. METHODS: Between 2006 and 2012, 118 patients with symptomatic popliteal cysts refractory to at least three months of guided physiotherapy were operated on by a single surgeon using a cyst wall and valve excising arthroscopic technique with intra-articular pathology management. Patients were evaluated preoperatively and at a mean follow-up of 39 months (range 12-71) by ultrasound, Rauschning and Lindgren, Lysholm, and VAS of perceived satisfaction scales. RESULTS: Ninety-seven out of 118 cases were available for follow-up. Recurrence was observed on ultrasound in 12/97 cases (12.4%); however, it was symptomatic only in 2/97 cases (2.1%). Mean scores improved: Rauschning and Lindgren from 2.2 to 0.4, Lysholm from 54 to 86, and VAS of perceived satisfaction from 5.0 to 9.0. No persistent complications occurred. Arthroscopy revealed simple cyst morphology in 72/97 (74.2%) and presence of a valvular mechanism in all cases. The most prevalent intra-articular pathologies were medial meniscus (48.5%) and chondral lesions (33.0%). There were significantly more recurrences in grade III-IV chondral lesions (p = 0.03). CONCLUSIONS: Arthroscopic popliteal cyst treatment had a low recurrence rate and good functional outcomes. Severe chondral lesions increase the risk of cyst recurrence.

Popliteal cysts are not a risk factor for lower extremity deep vein thrombosis.

BACKGROUND: Popliteal cysts (PC) result from distension of the gastrocnemio-semimembranosous bursa. Published reports indicate coincident PC and deep vein thrombosis (DVT). Whether the presence of PC increase the risk of deep vein thrombosis (DVT) remains unclear. METHODS: Lower extremity venous Duplex ultrasound (DUS) reports were evaluated across the Mayo Clinic Enterprise (Rochester, Minnesota, Jacksonville, Florida, Scottsdale, Arizona, and the Mayo Clinic Health System) in patients ≥ 18 years of age. Natural language processing (NLP) algorithms were created and validated to identify acute lower extremity DVT and PC from these reports. To determine whether there is a link between PC and lower extremity DVT, the frequency of PC among cases (ultrasounds with acute DVT) were compared to controls (ultrasounds without acute DVT). RESULTS: A total of 357,703 lower extremities venous DUS were performed in 237,052 patients (mean age 63.3 ± 16.6, 54.4% were female) between 1992 and 2021. Acute DVT was identified in 32,572 (9.1%) DUS, and PC in 32,448 (9.1%). PC were seen in a lower frequency (8.0%) of ultrasounds with acute DVT than those without (9.2%) acute DVT (OR: 0.85, 95% CI: 0.82 to 0.89, p < 0.001). In a multivariate logistic regression model after adjusting for age, sex, and race, PCs were not positively associated with acute DVT (adjusted OR: 0.84, 95% CI: 0.81 to 0.88). CONCLUSIONS: PC are an incidental finding or an alternative diagnosis on lower extremity venous DUS, a finding that increases significantly with age. PC were not a risk factor in the development of lower extremity DVT.

Comparison of arthroscopic internal drainage and open excision for the treatment of popliteal cysts.

BACKGROUND: The purpose of this study was to introduce the arthroscopic internal drainage with anterior-anteromedial approach for the treatment of popliteal cysts in children. To compare its clinical efficacy with open surgery. METHODS: This was a retrospective case-control study of 102 patients diagnosed with popliteal cysts from January 2018 to February 2020 who received surgery. The study included 27 cases with minimally invasive group (MI group) and 75 cases with open surgery group (OS group). The MI group included 21 males and 6 females, age 6.71 ± 2.16 years who received arthroscopic internal drainage of the cysts to adequately widen the valve opening between the cyst and the articular cavity, excised the fibrous diaphragm without complete excision of the cyst wall. The OS group included 57 males and 18 females, age 6.21 ± 1.67 years who received open excision. The clinical parameters regarding the preoperative characteristics and surgical results were compared. Ultrasound or MRI was used to identify the recurrence of the popliteal cysts. Rauschning-Lindgren grade was recorded to evaluate the clinical outcome. RESULTS: All patients were followed up for at least 24 months. There were no significant differences between the two groups in age, gender, left and right sides, disease time, cyst size, length of hospitalization, preoperative Rauschning-Lindgren grade (p > 0.05). At the last follow-up, the preoperative and postoperative Rauschning-Lindgren grade was improved in both groups. Compared with the OS group, operation time was significantly shortened in the MI group (28.89 ± 4.51 min vs 52.96 ± 29.72 min, p < 0.05). The MI group was superior to the OS group in terms of blood loss and plaster fixation, with statistical significance (p < 0.05). There was obvious difference in recurrence rate between the two groups (0% vs 17.33%, p = 0.018). No postoperative complications occurred during the follow-up period. CONCLUSIONS: Compared with open excision, the treatment of popliteal cyst in children by arthroscopic internal drainage to expand the articular cavity and eliminate the "one-way valve" mechanism between the cyst and the articular cavity exhibits better clinical outcomes and significantly reduces the recurrence rate, which is worthy of further clinical promotion.

Arthroscopic internal drainage of popliteal cysts with cyst wall resection in pediatric patients.

Objectives: To evaluate the efficacy of arthroscopic internal drainage (AID) and cyst wall resection (CWR) in children with popliteal cysts. Methods: This study included 16 pediatric patients with popliteal cysts and received arthroscopy using the double posteromedial (PM) portal system during June 2020 and June 2021 at The General Hospital of Northern Theater Command. Among these pediatric patients, 14 were males and two were females, with the mean age of nine years (range: 7-12 years). The left knee was affected in 12 cases, while the right knee was involved in the rest four cases. All patients underwent MR imaging before the procedure to assess whether there was intra-articular trauma and whether the popliteal cyst communicated with the knee-joint cavity. The MRI results showed that each patient had a simple popliteal cyst that involved a single knee joint without intra-articular trauma, which was classified as Grade-1 (n=3), Grade-2 (n =10) or Grade-3 (n =3) according to the Rauschning and Lindgren grading of knee joint symptoms. Arthroscopy was performed through anterolateral (AL) and PM portals to the knee joint for AID plus CWR, and the surgical outcomes were evaluated based on the Rauschning and Lindgren criteria. Results: No major vascular or nerve injury occurred during the operation. Postoperative complications such as wound infection and lower-extremity deep venous thrombosis were not recorded in these patients. Complications involving the saphenous nerve or the great saphenous vein or pseudocyst formation were not observed during the follow-up period. All patients completed the follow-up ranging from 3-12 months and were identified to have grade-0 (n=15) and grade-1 (n=1) popliteal cysts based on the Rauschning and Lindgren criteria, indicating significant improvement compared with the preoperative levels (all p<0.05). Moreover, no recurrence was recorded after operation. Conclusion: AID plus CWR is a minimally invasive and safe approach for pediatric patients with popliteal cysts to promote postoperative recovery and reduce the recurrence rate.

Factors affecting Baker cyst volume, with emphasis on cartilage lesion degree and effusion in the young and middle-aged population.

BACKGROUND: The principal aim of this study was to investigate the presence of factors affecting Baker's cyst volume in young and middle-aged populations. METHODS: Open cyst excision with valve and capsule repair, as well as knee arthroscopy, were used to treat eighty-five patients. The cases were categorized in terms of age, effusion, chondral lesion degree, meniscal tear degree, and Lindgren scores. An ultrasonography (USG) device was used to calculate the cyst volume. The IBM-SPSS 22 program was used for statistical analysis and to assess the relationships between variables using Spearman's correlation tests. RESULTS: The degree of chondral lesion was moderately and positively correlated with cyst volume in the total population (correlation coefficient: 0.469; p < 0.05). The degree of the chondral lesion was moderately and positively correlated with the degree of effusion (correlation coefficient: 0.492; p < 0.005). The cyst volume was weakly and positively correlated with the degree of effusion (correlation coefficient: 0.20; the correlation was at the limits of statistical significance p = 0.07 < 0.08). CONCLUSIONS: This study revealed that an increase in chondral lesion severity increases the amount of effusion and cyst volume.

Comparison of clinical outcomes associated with arthroscopic cyst wall preservation or resection in the treatment of popliteal cyst: a systematic review and meta-analysis.

OBJECTIVE: Arthroscopy is commonly used to treat popliteal cysts, but the influence of the cyst wall on treatment outcomes remains controversial. The goal of this study was to compare clinical outcomes associated with arthroscopic cyst wall resection versus preservation in patients undergoing treatment for popliteal cysts. METHODS: We searched the PubMed, Embase, Web of Science, and Cochrane Library databases to identify all relevant articles published as of April 2020. STATA v15.1 was used for all statistical analyses. Relative risk (RR) and corresponding 95% confidence intervals (CIs) pertaining to study outcomes were calculated. Study heterogeneity was evaluated using the I2 statistic and the χ2 test, with I2 > 50% and P < 0.10 as respective significance threshold values. The risk of bias was gauged with the Cochrane Collaboration's risk of bias tool and the Newcastle-Ottawa Scale (NOS). RESULTS: In total, 18 relevant studies were included in this meta-analysis, of which 16 were observational studies and 2 were randomized controlled trials (RCTs). These studies included 573 total patients, of whom 346 underwent arthroscopic cyst resection and 227 underwent arthroscopic cyst preservation. Pooled analyses revealed that clinical outcomes (RR = 0.98, 95% CI 0.94-1.00) and postoperative recurrence rates (RR = 0.90, 95% CI 0.85-0.95) were significantly better among patients that underwent cyst wall resection relative to those that underwent cyst wall preservation (RR = 0, 95% CI 0-0.02 and RR = 0.05, 95% CI 0.02-0.10, respectively). However, complications occurred more often in the cyst wall resection group relative to the cyst wall preservation group (RR = 0.05, 95% CI 0.01-0.12 vs. RR = 0.01, 95% CI 0-0.03). Sensitivity analyses confirmed the stability of these pooled results, and we detected no significant risk of publication bias. CONCLUSIONS: Relative to cyst wall preservation, popliteal cyst wall arthroscopic resection can yield more satisfactory clinical results and decrease rates of recurrence, but can also increase the incidence of complications. Future prospective studies comparing the outcomes associated with cyst wall resection and preservation will be required to validate our results.

The prevalence of Baker cyst in relation to the arrangement pattern between the medial head of gastrocnemius tendon and the semimembranosus tendon.

PURPOSE: The purpose of this study was to investigate whether Baker cyst (BC) was related to the specific arrangement of the medial head of gastrocnemius tendon (MHGT) and the semimembranosus tendon (SMT). MATERIALS AND METHODS: Patients who underwent knee MRI with "Baker cyst" in PACS from August 2017 to February 2018 were included in this study. Patients who did not have BC in a knee MRI performed during the same period were included in the control group. A total 210 patients were selected for inclusion in this study. For the imaging analysis, the arrangement pattern between MHGT and SMT was classified into three types: type 1, concave; type 2, flat; and type 3, convex. When imaging analysis was performed, the amount of effusion, the presence of osteoarthritis, and major ligament and meniscal tears were also described. Univariate and multivariate logistic regression analyses were performed. Statistical significance was considered at p < 0.05. RESULTS: The frequency of types 1, 2, and 3 was statistically significant depending on the presence or absence of BC (p < 0.001). The frequency of type 3 was the highest in the presence of BC, while that of type 1 was the highest in the absence of BC. BC was more common in type 2 (OR = 2.54; 95% CI = 1.27-5.07) and type 3 (OR = 4.09; 95% CI = 1.88-8.89). CONCLUSION: BC is more likely to occur in patients with SMT having a convex shape for MHGT. KEY POINTS: • Based on axial image of MRI only, one can predict which patients are morphologically more prone to develop a Baker cyst. • On axial images of MRI, Baker cyst is more likely to occur in patients with semimembranosus tendon having a convex shape for medial head of gastrocnemius tendon. • Baker cyst is not associated with the amount of effusion, OA, or internal derangement.

Clinical outcome of arthroscopic internal drainage of popliteal cysts with or without cyst wall resection.

BACKGROUND: This study aimed to compare the arthroscopic internal drainage of popliteal cysts alone or in combination with cyst wall resection in terms of clinical outcomes. METHODS: Forty-two consecutive patients with symptomatic popliteal cysts received arthroscopic treatment. Specifically, 20 of them received arthroscopic internal drainage (AI group) alone and 22 received arthroscopic internal drainage combined with cyst wall resection (AICR group) through double posteromedial portals. Magnetic resonance imaging (MRI) was performed to identify recurrence of popliteal cysts. The Lysholm score and Rauschning-Lindgren grade were used to assess the clinical outcomes. The median of the follow-up period was 24 months (12-48 months). RESULTS: The two groups (AI group and AICR group) were similar in age, gender, cyst diameter, associated joint disorder, preoperative Lysholm score, preoperative Rauschning-Lindgren grade and follow-up period (P > 0.05). Relative to the AI group, the AICR group had a significantly prolonged operation time (P < 0.05) and a higher incidence of complications (P < 0.05). In both groups, the Rauschning-Lindgren grade at the last follow-up significantly differed from the preoperative grade (P < 0.05) and the Lysholm knee score remarkably increased compared to the preoperative score (P < 0.05); however, there were no differences between the two groups at the last follow-up (P > 0.05). According to the MRI results, the cyst disappeared in 11 (55%), shrank in size in 6 (30%) and existed in 3 (15%) patients in the AI group, and was absent in 18 (81.8%) and shrank in size in 4 (18.2%) patients in the AICR group, suggesting a significant difference between the two (P < 0.05). CONCLUSION: Additional resection of cyst wall can result in a lower recurrence rate of cysts but extend the operation time and increase the incidence of perioperative complications compared with arthroscopic internal drainage of popliteal cysts alone.

A potential risk factor of total knee arthroplasty: an infected Baker's cyst - a case report.

BACKGROUND: In adults, Baker's cyst development is attributable principally to secondary alterations after degenerative changes. The latter changes often accompany osteoarthritis, and we frequently encounter patients with Baker's cysts seeking total knee arthroplasty (TKA). Baker's cysts are not usually subject to extensive preoperative evaluation because the cysts often disappear naturally after surgery, unaccompanied by any adverse symptoms. CASE PRESENTATION: A 63-year-old woman presented with moderate pain in the left knee joint that had developed 1 year ago. Posterior knee pain was aggravated on maximum knee flexion. Three months previously, a popliteal mass had become palpable and the patient had undergone needle mass aspiration twice in a local orthopedic hospital, but the mass had recurred. We initially considered TKA for her severe degenerative osteoarthritis. However, we decided to perform only arthroscopic debridement and cyst excision because the patient was experienced severe pain only on maximal knee flexion, and did not want TKA. Pus gushed from the torn cyst during the operation. We diagnosed an infected Baker's cyst. The patient was treated with a first-generation cephalosporin postoperatively. CONCLUSIONS: A Baker's cyst that was aspirated and still causes symptoms with altered blood tests needs to be evaluated accurately before TKA.

Is low dose radiotherapy an effective treatment for Baker's cyst?

PURPOSE: Osteoarthritis of the knee is a common disease, often associated with a Baker's cyst. Besides osteoarthritis, also other joint pathologies of the knee can be causative for a Baker's cyst. Radiotherapy is known to be an effective treatment for osteoarthritis, with an anti-inflammatory effect. As the excessive production of synovia usually is associated with intraarticular inflammation, our hypothesis was that radiotherapy might positively influence the synovial production and reduce the volume of a Baker's cyst. MATERIALS AND METHODS: We performed a prospective trial, including 20 knees receiving radiotherapy for knee arthritis. Besides documentation of NRS (numeric rating scale), WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) score and Knee Society Score, the volume of the Baker's cyst was calculated for a short- (6 to 12 weeks) and long-term (9 to 12 months) follow-up. Ultrasonic volumetry was performed using an ultrasound device with a high-resolution multifrequency linear probe (6-9 MHz). RESULTS: Low-dose radiotherapy improved NRS, WOMAC score and Knee Society Score significantly. The mean volume of Baker's cyst decreased from 22.3 ml to 10.7 respectively 3.1 ml during follow-up. A decrease in volume of more than 25% compared to the baseline could be achieved for 75% of the patients in the short-term and 79% of the patients in the long-term follow up. CONCLUSION: Radiotherapy of knee osteoarthritis is an effective treatment that decreases the volume of a Baker's cyst. Most patients respond to the treatment. Whether radiotherapy is an effective treatment for Baker's cyst without associated osteoarthritis has to be further examined.

Successful arthroscopic treatment of refractory and complicated popliteal cyst associated with rheumatoid arthritis in combination with osteoarthritis: case series and literature review.

Although popliteal cysts are most frequently identified in patients with osteoarthritis (OA), they may occur in patients with rheumatoid arthritis (RA), in which serious complicated cases such as cyst rupture can be developed. The objective of this study was to report four patients with RA (six knees) in combination with OA with a brief review of literature of previous similar published cases. This is a retrospective review of case records of patients with refractory and/or complicated popliteal cysts, who have successfully treated with arthroscopic intervention. We suggest that arthroscopic interventions such as radical debridement, synovectomy, biomechanical valve excision, and/or cystectomy should be considered in patients with refractory and complicated popliteal cysts associated with RA or RA in combination with OA.

Arthroscopic treatment of popliteal cyst using a figure-of-four position and double posteromedial portals.

PURPOSE: The purpose of this study was to introduce a modified arthroscopic treatment technique for popliteal cyst and hypothesize that this modified technique would provide good clinical efficacy and low recurrence rate. METHODS: From January 2013 to January 2017, 34 patients with symptomatic popliteal cysts were treated with our technique. A figure-of-four position and double posteromedial portals were used to achieve adequate enlargement of the posteromedial valvular opening between the cyst and the joint cavity and complete excision of the cyst wall. MRI was used to detect the recurrence of the popliteal cyst, and the Rauschning and Lindgren score was recorded to evaluate the clinical outcome. RESULTS: All patients were followed up with a mean period of 14.8 months (range, 12 to 36 months). Associated intra-articular lesions were found and treated in all cases. Degenerative cartilage damage was the most common pathology, which affected 23 (67.6%) of the cases. The Rauschning and Lindgren score improved significantly after surgery, and no evidence of recurrence was found from MRI in any case. CONCLUSIONS: Our modified arthroscopic treatment technique, using a figure-of-four position and double posteromedial portals, is effective and safe for treating popliteal cyst.

[The effect of arthroscopic synovectomy on refractory knee arthritis with popliteal cyst in 153 patients].

Objective: To investigate the efficacy of arthroscopic synovectomy on refractory knee arthritis complicated with popliteal cyst. Methods: Patients diagnosed as rheumatoid arthritis (RA) or spondyloarthritis (SpA) with refractory knee arthritis who underwent knee arthroscopic synovectomy in our hospital from 2010 to 2017 were enrolled, including 20 patients (16 RA, 4 SpA) with popliteal cyst. Clinical data, RA disease activity score (DAS28), SpA back pain score, etc, were collected to evaluate the efficacy of knee surgery. Results: Erythrocyte sedimentation rate (ESR) [58(17, 79)mm/1h vs. 19(9, 30)mm/1h, P< 0.001],C reactive protein (CRP) [3.72(0.92,8.14) mg/L vs. 0.85(0.10,3.08) mg/L,P<0.001], rheumatoid factor [64.6(20.2,193.3) vs. 20.5(10.0,58.4),P<0.001], DAS28 score(4.67±1.25 vs. 2.81±1.23,P<0.001), knee joint discomfort score [5(4,6) vs. 2(1,3),P<0.001] and the volume of knee joint effusion by ultrasound (P<0.05) in 95 RA patients were significantly decreased compared to those before operation. ESR [27(12,54)mm/1h vs. 20 (16,28) mm/1 h,P<0.001], CRP [3.27(1.06,6.95) mg/L vs. 1.41(0.34,3.03)mg/L,P<0.001],knee discomfort score [2(0,5) vs. 1(0,3),P<0.05], back pain visual analogue score (VAS) [5(4,5) vs. 2(1,3), P<0.001], and the volume of knee joint effusion by ultrasound (P<0.001) in 58 SpA patients were significantly lower than those before the operation.The rate [16.84%(16/95) vs. 6.32%(6/95),P=0.023] and grading (P=0.007) of popliteal cyst in RA were decreased after the operation. No statistically difference was observed in the rate [6.90% (4/58) vs. 5.17%(3/58), P=0.697] of popliteal cyst in patients with SpA, yet with a trend of decrease in 4 patients. Conclusion: This study provide evidence that knee arthroscopic synovectomy has a good effect for refractory knee arthritis, which can reduce disease activity, improve joint symptoms and decrease the grading of popliteal cyst.

Clinical outcome of arthroscopic management of popliteal cysts with or without additional posterior open cystectomy.

PURPOSE: The aim of this retrospective study was to compare the clinical outcomes of arthroscopic decompression of popliteal cysts and simultaneous management of intra-articular pathologies alone or in combination with posterior open cystectomy. MATERIAL AND METHODS: This study included 65 consecutive patients with the diagnosis of popliteal cysts. Of the patients 31 received arthroscopy alone (arthroscopic decompression of cysts and management of intra-articular pathologies, AA group) and 34 received arthroscopy combined with open cystectomy (AO group). At the last follow-up after a mean of 33.3 months, magnetic resonance imaging (MRI) scans were performed to assess the outcomes of cysts and functional scores. The Lysholm score and Rauschning and Lindgren grade were used for clinical evaluation. RESULTS: The procedure in the AA group took less time to perform and resulted in less postoperative complications in the perioperative period. At the last follow-up, no significant differences were observed between the groups in terms of the Lysholm score or Rauschning and Lindgren grade (P > 0.05). The results of MRI showed that the cysts disappeared in 17 (55%) patients, reduced in 9 (29%) patients and persisted in 5 (16%) patients in the AA group, and disappeared in 29 (85%) patients, reduced in 4 (12%) patients and persisted in 1 (3%) patients in the AO group, which was significantly different (P < 0.05). In the AA group 6 patients and 1 in the AO group were grade 2 or 3 and needed a second operation (arthroscopy combined with open cystectomy), which was significantly different (P < 0.05). CONCLUSION: In comparison to arthroscopic decompression of cysts and management of intra-articular pathologies alone, the additional posterior open cystectomy reduced the recurrence of popliteal cysts, although it took longer to perform and brought more perioperative complications.

Popliteal cyst before William Baker: first report in the Galenic Corpus.

INTRODUCTION: A popliteal cyst, also known as Baker cyst, is a benign fluctuant swelling of the gastrocnemius-semimembranosus bursa in the popliteal fossa at the back of the knee. The cyst is named after William Morrant Baker, who is considered to have first described this fluid collection with new sac formation outside of the knee-joint in 1877. We herein present a short description contained in the Galenic Corpus that appears to match to what we now call the Baker cyst. MATERIAL AND METHODS: Α thorough survey of Kühn's Galenic Corpus was performed. RESULTS: The 14th book of Kühn's edition contains a brief review of all the anatomical structures and pathologies. In the 17th chapter of this treatise, devoted to skin lesions, the author states that steatomas appear in the popliteal fossa. However, it is no more believed to reflect the Galenic teaching and is ascribed to Pseudo-Galen. DISCUSSION: With regard to the descriptions survived and the anatomy knowledge in the post-Galenic era time, the brief report of the ancient text of unknown origin, appears to match what we now describe as popliteal cyst.

Treatment of baker cyst, by using open posterior cystectomy and supine arthroscopy on recalcitrant cases (103 knees).

BACKGROUND: Associated joint disorders with popliteal cysts were stated approximately between the ranges of 41-83 % in all reported cases. Combined treatment strategies that eliminate intra-articular pathologies and cyst- associated valve mechanisms are thought to be a good option in treatment of the disease. In this study, our main objective is to present clinical results of our combined treatment results, which includes posterior cyst excision with supine arthroscopic intervention, targeting intra-articular pathologies on recalcitrant cases. METHODS: One hundred three knees of 100 patients treated with posterior open cystectomy with valve and repair of posterior capsule, in addition to arthroscopic treatment of intra-articular lesions, were included in the study. Preoperative magnetic resonance imaging (MRI) studies were performed in order to evaluate location of Baker cysts behind the knee. Rauschning-Lindgren and Lysholm Knee Scoring Scales were used to assess pre/post-operative knee functions. Mann-Whitney U test was used to evaluate the differences between genders in comparison of Lysholm and Lindgren scores. Mean age within gender groups was compared using independent samples t-test. Wilcoxon test was used to compare the change in Lysholm and Lindgren scores. A p-value of less than 0.05 was considered to show a statistically significant result. Over the 1-year follow-up period, US and MR imaging was performed only with symptomatic patients. RESULTS: Cyst recurrence was seen only in 2 (1.94 %) patients. Post-operative Lysholm Knee and Lindgren knee scores demonstrated improvement in knee function and general comfort level of the patients. CONCLUSIONS: Our midterm follow-up (Mean: 39 Months) results showed that open cyst excision with valve and capsule repair with knee arthroscopy that targets associated intra-articular pathologies reduced the pain and improved the knee function in those patients. LEVEL OF EVIDENCE: IV (Retrospective clinical study without comparison group).

[Arthroscopic procedure for Baker's cysts : surgical technique. Video article]. / Arthroskopische Operation der Baker-Zyste : Operationstechnik. Videobeitrag.

BACKGROUND: Baker's cysts are related to increased intra-articular pressure. The causes may be inflammatory, degenerative or traumatic disorders. Owing to the increased intra-articular pressure a cyst protrudes between the semimembranosus and the medial gastrocnemius tendons. The traditional treatment for a Baker's cyst is open resection. As an alternative, an arthroscopic procedure can be performed, which is demonstrated by the video on surgical technique that accompanies this short report. SURGICAL TECHNIQUE: From the anterolateral portal the arthroscope is advanced through the intercondylar notch (below the posterior cruciate ligament) to the posteromedial recess. Under visual control, a posteromedial portal is created followed by identification of the capsular fold separating the cyst from the joint cavity. This fold (valvular mechanism) is resected with a shaver from the posteromedial portal until a large enough connection exists between the joint and the cyst (cyst decompression). After the decompression, the arthroscope is inserted from the posteromedial portal directly into the cyst cavity. Subsequently, the inner wall of the cyst is removed with the shaver via an additional far posterior cystic portal. It is obligatory to treat the associated intra-articular pathological condition. In our video a medial meniscal lesion is treated with partial meniscectomy.