Clinical results of direct arthroscopic excision of popliteal cyst using a posteromedial portal

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.

Risk factors for residual popliteal cyst after arthroscopic decompression and cystectomy: Associated with degenerative cartilage lesions

BACKGROUND

In previous studies, good results have been reported after arthroscopic treatment of popliteal cysts and concomitant intra-articular pathology. However, only a few studies have reported the associated factors with residual popliteal cysts. The aim of this study was to examine the clinical and radiographic outcomes and investigate the factors associated with the recurrence of popliteal cyst after arthroscopic cyst decompression and cyst wall resection.

HYPOTHESIS

The authors hypothesized that residual popliteal cyst after arthroscopic decompression and cystectomy would be associated with degenerative cartilage lesions.

PATIENTS AND METHODS

From December 2010 to December 2018, 54 patients with popliteal cysts were treated with arthroscopic decompression and cyst wall resection through an additional posteromedial cystic portal. Magnetic resonance imaging (MRI) or ultrasonography was used to observe whether the popliteal cyst had disappeared or decreased. The maximum diameter of the popliteal cyst was measured after surgery. The patients were classified into the disappeared and reduced groups according to the treatment outcome. Age, sex, symptom duration, preoperative degenerative changes based on the Kellgren-Lawrence (K-L) grade, cartilage lesions according to the International Cartilage Repair Society (ICRS) grades, synovitis, functional outcomes, and associated intra-articular lesions were compared between the two groups. The functional outcome was evaluated on the basis of the Rauschning and Lindgren knee score. The study included 22 men and 32 women, with mean age of 49.6 years (range, 5-82 years). According to the ICRS grade system, 28 (51.8%) patients had grade 0 to II, 26 (48.2%) patients had grade III to IV.

RESULTS

Follow-up radiographic evaluation revealed that the cyst had completely disappeared in 20 patients (37%) and reduced in size in 34 (63%). The mean cyst size was decreased significantly from 5.7cm (range, 1.7-15cm) to 1.7cm (range, 0-6.4cm), and the Rauschning and Lindgren knee score showed improved clinical features in all the patients. Between the disappeared and reduced groups, the presence of degenerative cartilage lesions (p=0.022, odds ratio 8.702, 95% confidence interval: 1.368-55.362) showed statistically significant differences.

DISCUSSION

Through the posteromedial cystic portal, cysts were completely removed in approximately 40% of patients, and the size was reduced in 60% of patients. Presence of degenerative cartilage lesion represents an associated risk factor for residual popliteal cyst. These findings could be helpful in ensuring explaining poor prognostic factors.

LEVEL OF EVIDENCE

IIIb; retrospective cohort study.

Double posteromedial portals versus single posteromedial portal for arthroscopic management of popliteal cysts

BACKGROUND

As a common disease in orthopedic clinics, popliteal cysts often coexist with intra-articular lesions. Compared with traditional open surgery, arthroscopic treatment of popliteal cysts is less traumatic, and intra-articular lesions can be treated. The 'one-way valve' mechanism of the popliteal cyst can be removed by expanding the communication between the articular cavity and the cyst to avoid cyst recurrence. In terms of arthroscopic techniques, the comparison of clinical effects between the double posteromedial portal (DPP) and single posteromedial portal (SPP) has rarely been studied. The purpose of this retrospective study was to compare the clinical effects of DPP and SPP.

METHODS

A total of 46 consecutive patients with symptomatic popliteal cysts who underwent arthroscopic treatment were included in this study and followed for approximately 1 year. All patients were divided into two groups according to the arthroscopic portals (DPP group and SPP group). The cyst size, Lysholm score and Rauschening-Lindgren (R-L) grade were evaluated before the operation for all patients, and the intra-articular lesions, operative time and complications were recorded after operation. At the last follow-up, the Lysholm score and R-L grade were recorded, and magnetic resonance imaging was used to evaluate the outcome of the cyst. The clinical data of the two groups was statistically compared and analyzed.

RESULTS

There were no significant differences in preoperative cyst size, Lysholm score or R-L grade between the two groups (P > 0.05). The operation time of the DPP group (67.52 ± 18.23 min) was longer than that of the SPP group (55.95 ± 16.40 min) (P = 0.030), but the recurrence rate of cysts in the DPP group (0%) was obviously lower than that in the SPP group (19.0%) (P = 0.046). There were no significant differences in the Lysholm score, R-L grade or complication rate between the two groups at the last follow-up (P > 0.05).

CONCLUSION

Arthroscopic treatment of popliteal cysts using double posteromedial portals was a safe and effective surgical method.

TRIAL REGISTRATION

ChiCTR, ChiCTR2200060115. Registered 19 May 2022, https://www.chictr.org.cn/showproj.html?proj=133199.

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.

Arthroscopic Internal Drainage with Cyst Wall Resection and Arthroscopic Internal Drainage with Cyst Wall Preservation to Treat Unicameral Popliteal Cysts: A Retrospective Case-Control Study

Objective

To compare the clinical efficacy and safety of arthroscopic internal drainage for the treatment of unicameral popliteal cysts with or without cyst wall resection.

Methods

This was a retrospective case–control study of 73 patients diagnosed with unicameral popliteal cysts from January 2012 to January 2019 who received arthroscopic treatment. The study included 38 cases with cyst wall resection (CWR group) and 35 cases with cyst wall preservation (CWP group). The CWR group consisted of 14 men and 24 women with an average age of 51.8 years, while the CWP group consisted of 13 men and 22 women with an average age of 52.0 years. All patients were examined for intra‐articular lesions and communicating ports by magnetic resonance imaging (MRI) prior to surgery, and recurrence of cysts was evaluated at the last follow‐up examination. Rauschning and Lindgren grade (R–L grade) and Lysholm score were used to evaluate clinical outcomes. In addition, operation time and complications were recorded.

Results

The average length of follow‐up was 24.2 months (range, 16 to 32 months). There were no considerable differences in age, gender, cyst size, Lysholm score, R–L grade and concomitant intra‐articular cases between the CWR group and CWP group prior to surgery (P > 0.05). The last follow‐up MRI scans showed that in the CWR group, the cyst disappeared in 25 cases and shrunk in 13 cases. In the CWP group, the cyst disappeared in 22 cases, shrunk in 12 cases and persisted in one case. There was no obvious difference in recurrence rate between the two groups (0% vs 2.9%, P = 0.899). At the last follow‐up, there were no differences in the R–L grade (P = 0.630) and Lysholm score (88.3 ± 5.6 points vs 90.1 ± 3.8 points, P = 0.071) between the two groups. Compared with the CWP group, operation time was significantly prolonged in the CWR group (38.3 ± 3.1 min vs 58.3 ± 4.4 min, P < 0.05). In the CWR group, three cases occurred fluid infiltration under the gastrocnemius muscle, which improved after pressure bandaging and cold compress. In another three cases, hematoma was found. The incidence of complications in the CWR group was markedly higher than that in the CWP group (15.8% vs 0%, P < 0.05). During the follow‐up period, none of the patients developed serious complications such as neurovascular injury, deep venous thrombosis, or infection.

Conclusion

For unicameral popliteal cysts, arthroscopic internal drainage combined with resection of the cyst wall did not further improve the clinical outcomes or reduce the recurrence rate, while prolonging the operation time and increasing the possibility of complications.

Popliteal Cysts: A Systematic Review of Nonoperative and Operative Treatment

BACKGROUND

Treatment methods for popliteal cysts have varied over the past several decades and have posed challenges to providers as recurrences were frequent. With greater understanding of relevant anatomy, both operative and nonoperative treatment methods have evolved to appropriately target relevant pathology and improve outcomes. The purposes of this review were to outline the evolution of treatment methods and to qualitatively summarize clinical outcomes.

METHODS

We performed a systematic review on treatments for popliteal cysts to include publications from 1970 to 2019. Other inclusion criteria consisted of studies with ≥10 patients enrolled, studies with a patient age of ≥16 years, studies with an adequate description of the treatment technique, and studies with a Level of Evidence of IV or higher. The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and literature quality was assessed using a modified Coleman methodology score.

RESULTS

Thirty studies met inclusion criteria in this review. Nine studies discussed nonoperative treatment, and 21 studies discussed operative treatment. Eight of the 9 nonoperative treatment studies utilized corticosteroid injections. The most recent studies have advocated for ultrasound-guided intracystic injection with possible cyst fenestration. Most operative studies utilized an arthroscopic approach to enlarge the communication with the joint space. However, alternative treatment techniques are still utilized.

CONCLUSIONS

The current literature on the treatment of popliteal cysts indicates that intracystic corticosteroid injection with cyst fenestration is an effective nonoperative treatment method. Arthroscopic surgical procedures with enlargement of the communication have been most widely studied, with positive results; however, further studies are needed to confirm superiority over other treatment methods.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Ultrasound-guided arthroscopic communication enlargement surgery may be an ideal treatment option for popliteal cysts - indications and technique

PURPOSE

Several studies have shown an excellent success rate of communication enlargement surgery for popliteal cysts (Baker's cysts). Ultrasound-guided surgery can improve the accuracy of this procedure and may lead to better outcomes. This study describes a simple ultrasound-guided arthroscopic technique to manage popliteal cysts and reduce postoperative pain.

METHODS

After routine arthroscopic observation with a standard 2-portal approach, the arthroscope is redirected toward the posteromedial compartment from the anterolateral portal through the intercondylar notch. A posteromedial portal is then placed at this view. Subsequently, a contrast dye (indigo carmine) is injected into the popliteal cyst percutaneously using ultrasonography. This procedure makes it easier to find a capsular fold or valvular opening. The valvular opening between the semimembranosus and medial gastrocnemius is enlarged with a shaver and radiofrequency ablation. Cystectomy is not performed in any case. Finally, the irrigation fluid is suctioned, and the reduced cyst is visualized by ultrasound. Additionally, a periarticular multimodal drug injection is administered into the septum and inner wall of the cyst under ultrasound guidance.

CONCLUSIONS

Ultrasound-guided arthroscopic surgery for popliteal cysts can ensure reproducibility and be effective for postoperative pain relief. Thus, this combined procedure may be an optimal treatment option.

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 comparison of the clinical effects of arthroscopic treatment for popliteal cyst between techniques using one posteromedial portal and two posteromedial portals

There is a lack of research comparing the clinical effects of arthroscopic treatment of popliteal cysts between the one posteromedial portal (OPP) technique and the two posteromedial portals (TPP) technique. The aim of this study was to evaluate and compare the clinical efficacy of arthroscopic treatment for popliteal cysts between the 2 techniques.Patients with symptomatic popliteal cysts after surgery were retrospectively invited to participate in this study. They received arthroscopy treatment via the OPP technique or the TPP technique. At the final follow-up, the Rauschning and Lindgren criteria and the Lysholm score were used for clinical evaluation. Moreover, magnetic resonance imaging was performed to detect the recurrence of cysts postoperatively.Finally, 53 patients with symptomatic popliteal cysts were included in this study, including 25 in the OPP group and 28 in the TPP group. The operation time of the TPP group was significantly longer than that of the OPP group (P < .001). In the OPP group, the cysts disappeared in 17 patients and reduced in size in 8 patients. In the TPP group, the cysts disappeared in 23 patients and reduced in size in 5 patients. According to the Rauschning and Lindgren classification, the recurrence rate was significantly lower in the TPP group (0%) than in the OPP group (4%) (P = .03). In addition, there was no significant difference in the Lysholm score between the OPP group and the TPP group (P = .77).TPP technique is more effective and superior than OPP technique for the treatment of popliteal cysts.

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.

Arthroscopic Treatment of Popliteal Cysts with and without Cystectomy: A Systematic Review and Meta-Analysis

PURPOSE

To compare the clinical outcomes of the arthroscopic treatments for popliteal cysts with and without cystectomy.

METHODS

PubMed/MEDLINE, EMBASE, KoreaMed, and Cochrane Library were searched from the earliest available date of indexing through August 2016. The methodological quality of all articles was assessed according to the Coleman methodology score (CMS). Studies were grouped according to the surgical method, and a meta-analysis was conducted to identify the unsuccessful clinical outcome and complication rates.

RESULTS

Nine studies were included; the mean CMS was 67.33 (standard deviation, 8.75 points). Cystectomy was reported in five studies; cystectomy was not performed in four studies. The odds ratio of unsuccessful clinical outcomes evaluated by Rauschning and Lindgren score was 122.05 (p<0.001) with cystectomy and 58.12 (p<0.001) without cystectomy. The effect size of complications was 0.16 (p<0.001) with cystectomy and 0.03 (p<0.001) without cystectomy. The recurrence rate was 0% with cystectomy and 6.4% without cystectomy.

CONCLUSIONS

All the currently available studies showed satisfactory outcomes in both with and without cystectomy groups. However, arthroscopic cystectomy concurrently performed with management of intra-articular lesions was associated with a relatively low recurrence rate and a relatively high incidence of complications.

Extra-articular endoscopic excision of symptomatic popliteal cyst with failed initial conservative treatment: A novel technique

To reduce the damage to posteromedial knee capsule, we developed a direct extra-articular arthroscopic approach for excision of symptomatic popliteal cysts. This study aimed to demonstrate the surgical technique and present the 2-year follow-up results. Cystectomy is performed by extra-articular surgical approach through a high posteromedial portal. Twenty-one consecutive patients diagnosed of symptomatic popliteal cysts with failed initial conservative treatments were included. At a median follow-up of 29.4 months, all knees had improved clinical function assessed by Rauschning and Lindgren knee classification (p<0.001). The cysts were either disappeared (95.2%) or reduced in size (4.8%). Only one (4.8%) patient had recurrent cyst, which was solved after ultrasound-guided aspiration. This direct extra-articular arthroscopic technique could be a feasible alternative for treatment of symptomatic popliteal cysts.

[Clinical prospective comparative study on short-term effectiveness of arthroscopic treatment of popliteal cyst between cyctectomy and internal drainage combined with cyctectomy]

Objective

To compare the short-term effectiveness between arthroscopic cystectomy and internal drainage combined with cystectomy in popliteal cyst.

Methods

Between March 2014 and March 2017, 56 patients with symptomatic popliteal cyst were enrolled in the study, randomized block design was used to divided the patients into trial group (arthroscopic cystectomy combined with internal drainage group, n=28) and control group (arthroscopic internal drainage group, n=28). Excluding those who had incomplete follow-up and received surgery for other diseases postoperatively, 26 patients in the experimental group and 27 patients in the control group were finally enrolled in the study. There was no significant difference in gender, age, side, course of disease, maximum diameter and grade of popliteal cyst, and associated diseases between two groups ( P>0.05). The operation time, duration of popliteal ecchymosis and the middle back of calf tenderness were observed postoperatively. The circumference of calf at 1 day, 1 week, and 2 weeks after operation were measured and the differences were calculated with the measurement before operation. Lower extremity venous thrombosis was observed by color doppler ultrasonography at 1 week after operation. The effectiveness was evaluated by Rauschning and Lindgren grading criteria. And MRI was used to observe whether the popliteal cyst disappeared or decreased and measured its maximum diameter at 1 year after operation.

Results

Patients in both groups were followed up 12-14 months, with an average of 12.5 months. The operation time, duration of popliteal ecchymosis, and the middle back of calf tenderness of the trial group were all longer than those in the control group ( P<0.05), the differences of circumference of calf at 1 day, 1 week, and 2 weeks after operation of the trial group were greater than those in the control group ( P<0.05). Color doppler ultrasonography of the lower extremity at 1 week after operation found that the intermuscular venous thrombosis occurred in 2 cases of the trial group, while no lower extremity thrombosis was found in the control group; and the difference between two groups was not significant ( P=0.236). According to the Rauschning and Lindgren grading criteria, there were 16 cases of grade 0, 6 cases of grade 1, and 4 cases of grade 2 in the trial group, and 17 cases of grade 0, 4 cases of grade 1, and 6 cases of grade 2 in the control group at 1 year after operation. There was no significant difference between 2 groups ( Z=-1.872, P=0.078). Nine cases (34.62%) of the trial group and 13 cases (48.15%) of the control group still have residual cysts by MRI, the maximum diameter of which was less than 2 cm. The cysts disappeared in the remaining patients in both groups, and there was no recurrence during the follow-up. There was no significant difference in cyst residual rate between 2 groups ( χ ²=2.293, P=0.852).

Conclusion

Compared with arthroscopic internal drainage, the short-term effectiveness of the arthroscopic internal drainage combined with cystectomy had no significant improvement, and the operation time was prolonged, the postoperative complications were obviously increased.

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.

Arthroscopic internal drainage and cystectomy of popliteal cyst in knee osteoarthritis

Background

The purpose of this study was to evaluate the efficacy of arthroscopic knee cavity internal drainage and cyst cavity debridement operation of popliteal cyst in knee osteoarthritis patients.

Methods

From August 2007 to March 2013, 58 knee osteoarthritis patients with popliteal cyst were treated with arthroscopic knee cavity internal drainage through posteromedial portal and popliteal cyst cavity debridement through superior posteromedial portal. In all patients, preoperative magnetic resonance imaging (MRI) was performed to detect combined intra-articular pathology and the communication between popliteal cyst and knee cavity. Clinical efficacy was evaluated through VAS score and Lysholm score.

Results

All patients had neither recurrence of popliteal cyst nor complaints of pain, swelling, or functional impairment at average 24 months follow-up after surgery. Postoperatively, VAS score was decreased significantly and Lysholm score was raised significantly comparing preoperatively.

Conclusion

Arthroscopic knee cavity internal drainage operation through posteromedial portal and popliteal cyst cavity debridement through superior posteromedial portal is an effective minimally invasive surgery method for the treatment of popliteal cyst without recurrence in knee osteoarthritis patients.

Giant Baker's Cyst Associated with Rheumatoid Arthritis

We report a rare case of a "giant Baker's cyst-related rheumatoid arthritis (RA)" with 95 × 26 mm dimensions originating from the semimembranosus tendon. The patient presented with chronic pain and a palpable mass behind his left calf located between the posteriosuperior aspect of the popliteal fossa and the distal third of the calf. In MRI cystic lesion which was located in soft tissue at the posterior of gastrocnemius, extensive synovial pannus inside and degeneration of medial meniscus posterior horn were observed. Arthroscopic joint debridement and partial excision of the cyst via biomechanical valve excision were performed. The patient continued his follow-up visits at Rheumatology Department and there was no recurrence of cyst-related symptoms in 1-year follow-up. Similar cases were reported in the literature previously. However, as far as we know, a giant Baker's cyst-related RA, which was treated as described, has not yet been presented.

Popliteal (Baker's) Cysts in the Setting of Primary Knee Arthroplasty

BACKGROUND

Popliteal (Baker's) Cysts are rare complications of knee arthroplasty. Enlargement, irritation, or rupture of the cyst can lead to significant pain, tightness, and tenderness. The literature regarding popliteal cysts occurring following knee arthroplasty is limited and does not report prevalence, natural history, and treatment of popliteal cyst in the setting of knee arthroplasty.

METHODS

Following Institutional Review Board approval, 2,025 primary total and partial knee arthroplasties by four surgeons at one institution from 2011-2016 were reviewed for occurrence of popliteal cysts. Twelve cases occurring after arthroplasty were identified, including four unicompartmental knee arthroplasties and eight total knee arthroplasties. Demographic data were evaluated and symptoms, time of onset following arthroplasty, attempted treatment strategies, and success or failure of attempted treatments or interventions were recorded.

RESULTS

The mean age of patients that presented with a popliteal cyst was 63.6 years old (range = 45 - 78 years). There were 5 males and 7 females. The mean BMI was 26.32 (range = 19.0 - 35.0). In 2,205 primary knee arthroplasties performed from 2011-2016 (including 175 partial and 1850 total), the prevalence of popliteal cysts following surgery was 0.6% (n=12). All popliteal cysts were discovered between six weeks and two years following surgery, with the majority occurring during the first year. Twenty-five percent (3/12) of patients presented with minimal symptoms. These were managed expectantly. Seventy-five percent (9/12) were symptomatic. One patient had only a diagnostic ultrasound, two patients underwent ultrasound-guided aspiration and steroid injection, three underwent simple aspiration. Two underwent surgical excision. One cyst ruptured. All cases went on to symptomatic resolution. There was no association with diabetes, smoking, or body mass index. A disproportionately high number (25% or 4/12) occurred in partial knee arthroplasty.

CONCLUSION

While popliteal cysts following primary total knee arthroplasty are rare, they can become a persistent and even disabling problem for arthroplasty patients. Given the lack of formalized recommendations in the existing literature, we propose a treatment algorithm that has been successful in our clinic, including observation initially, ultrasound-guided injection/aspiration if symptomatic, and surgical excision as a last resort.

LEVEL OF EVIDENCE

Level IV.

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 management of popliteal cysts

BACKGROUND

Management of popliteal cyst is controversial. Owing to high failure rates in open procedures, recent trend is towards arthroscopic decompression and simultaneous management of intraarticular pathology. We retrospectively analysed clinical results of symptomatic popliteal cysts after arthroscopic management at 24 month followup.

MATERIALS AND METHODS

Retrospective analysis of hospital database for patients presenting with pathology suggestive of a popliteal cyst from June 2007 to December 2012 was done. Twelve cases of popliteal cyst not responding to NSAIDS and with Rauschning and Lindgren Grade 2 or 3 who consented for surgical intervention were included in the study. All patients underwent arthroscopic decompression using a posteromedial portal along with management of intraarticular pathologies as encountered. Furthermore, the unidirectional valvular effect was corrected to a bidirectional one by widening the cyst joint interface. The results were assessed as per the Rauschning and Lindgren criteria.

RESULTS

All patients were followed for a minimum of 24 months (range 24-36 months). It revealed that among the study group, six patients achieved Grade 0 status while five had a minimal limitation of range of motion accompanied by occasional pain (Grade 1). One patient had a failure of treatment with no change in the clinical grading.

CONCLUSION

Arthroscopic approach gives easy access to decompression with the simultaneous management of articular pathologies.

Surgical treatment of popliteal cyst: a systematic review and meta-analysis

BACKGROUND

This systematic review and meta-analysis of the clinical efficacy of different surgical methods in the therapy of popliteal cysts may provide evidence about effective surgical treatments.

METHODS

PubMed, EMBASE, and OVID were searched with the following terms: (popliteal cyst* OR baker's cyst*) AND (arthroscopic OR excision OR operative OR treat* OR surgery). Inclusion criteria included the following: studies reported the efficacy of different surgical methods in popliteal cyst patients; patients were ≥ 16 years; and studies must have involved a minimum of 10 patients. Studies were grouped according to the surgical methods, and a meta-analysis was employed to identify the success rate based on the pooled data.

RESULTS

A total of 11 studies were included: The communication between the cyst and the articular cavity was enlarged in 7 studies; this communication was closed in 3 studies; and only intra-articular lesions were managed in 1 study. After the data were pooled, the success rates were 96.7 and 84.6 % in the communication-enlargement group and communication-closure group, respectively. Studies with communication enlargement were subgrouped into the cyst wall resection group and the non-cyst wall resection group, for which the success rates were 98.2 and 94.7 %, respectively.

CONCLUSIONS

Based on the current available evidence, at present, any how arthroscopic excision of the cyst wall, arthroscopic management of intra-articular lesions, and enlarging the communication between the cyst and the articular cavity is an ideal strategy for the popliteal cyst. The current literature on the treatment of popliteal cysts is limited to retrospective case series. Future prospective studies with high-quality methodology and uniform scoring system are required to directly compare communication-enlargement surgery and communication-closure surgery and determine the optimal treatment of popliteal cysts. Cyst wall resection may improve the therapeutic efficacy, to draw definitive conclusions, and high-level clinical researches with a large number of patients and long-term follow-up should be initiated.

Arthroscopic patterns of the poster-medial aspect of the knee joint: classification of the gastrocnemius-semimembranosus gateway and its relationship with Baker's cyst

BACKGROUND

The gastrocnemius-semimembranosus bursa may communicate with the knee joint. The arthroscopic anatomy of the posteromedial aspect varies depending on the angle of the oblique popliteal ligament, the level at which it crosses the medial gastrocnemius tendon, and its relationship with the capsular joint and synovia. The aim of this paper is to identify possible patterns, and to evaluate their characteristics and their relationship with Baker's cyst.

METHODS

data archived from 185 consecutive arthroscopies were evaluated; an anatomic description and classification was carried out; the percentages of association with BC and the associated pathologies were reported.

RESULTS

The different anatomies were classified into six groups based on the relationship above the medial gastrocnemius tendon, the capsular joint and synovia. The prevalence of Baker's cyst was 28.3%. The main associated intra-articular pathological condition was the contemporary presence of a meniscal tear and chondropathy.

CONCLUSION

Exploration of the posterior aspect of the knee must be performed routinely. Knowing the possible anatomy patterns of the posteromedial arthroscopic aspect of the knee joint could help to identify the cyst and its gateway, thus facilitating its treatment.

LEVEL OF THE EVIDENCE

III.

Treatment of popliteal cysts via arthroscopic enlargement of unidirectional valvular slits

OBJECTIVE

The aim of the present study was to investigate the efficacy of arthroscopic enlargement of unidirectional valvular slits for the treatment of popliteal cysts and to evaluate potential factors affecting the outcomes of our arthroscopic procedure.

METHODS

Twenty-nine patients aged 43-77 years with popliteal cysts were treated with arthroscopic cyst decompression. Surgery was performed via two posterior portals after creating a transseptal portal. Rauschning and Lindgren clinical score, magnetic resonance images, and osteoarthritic grade were evaluated pre- and postoperatively, and cartilage degeneration class was confirmed via arthroscopy. The mean follow-up period was 22.9 ± 14.6 months (range, 9-60 months).

RESULTS

Twelve cysts disappeared completely (group D), while 16 reduced and one enlarged (group R) in size by the final follow-up. Twenty-two (75.9%) of 29 popliteal cysts diminished to a volume that was less than 10% of the preoperative volume. Clinical scores improved in 93.1% of the patients, and more patients (68.8%) in group R had positive joint effusion at the final follow-up compared with group D (17.7%; p < 0.01).

CONCLUSIONS

Arthroscopic cyst decompression was effective in the treatment of symptomatic popliteal cysts. Intra-articular pathologies associated with joint effusion should be corrected simultaneously.

Arthroscopic Treatment of Popliteal Cyst: A Direct Posterior Portal by Inside-Out Technique for Intracystic Debridement

Popliteal cysts are characterized by enlargement of the gastrocnemius-semimembranosus bursa. The pathogenesis includes a valvular opening between the knee joint and the bursa, and associated intra-articular pathology may give rise to knee effusion. The mainstay of treatment is conservative. If popliteal cysts are symptomatic, analgesia, aspiration, and steroid injection therapy may be considered, but most recur rapidly. In the past, open excision was an option if they remained symptomatic, but the associated recurrence rate was high. One important reason was that the intra-articular pathology causing the knee effusion was not treated. We present an alternative minimally invasive arthroscopic treatment using dye (methylene blue) directly injected into the cyst, which will leak from the cyst into the joint, to identify the valvular opening. The thickened valve is opened using a basket forceps and then enlarged using a motorized shaver to disrupt the 1-way mechanism between the joint and bursa, as well as to establish an unobstructed freeway connection between them. We also present a safe technique to create a direct posterior portal. Intracystic debridement of the fibrous membrane, nodules, and septa through this portal will decrease the recurrence rate of the popliteal cyst.

The association between Baker's cyst and medial meniscal tear in patients with symptomatic knee using ultrasonography

INTRODUCTION

There are nearly no studies about the association between Baker's cyst (BC) and medial meniscal tear (MMT) using ultrasonography.

PATIENTS AND METHODS

Nonselected patients who were referred for ultrasonography for the evaluation of knee pain were recruited. Demographic, clinical, and ultrasound parameters were documented.

RESULTS

One-hundred and nineteen patients were included and 131 knees were evaluated. There were 59 (~50%) female patients and mean age of 46.4±17.7 years. BC was found in 31 knees (23%). BC was significantly associated with MMT (P=.029) and age (P=.002) after adjusting for other covariates.

CONCLUSIONS

BC was strongly associated with MMT regardless of other intraarticular abnormalities.

Popliteal cysts: a current review

Baker's cyst, or popliteal cyst, is a fluid-filled mass that is a distention of a preexisting bursa in the popliteal fossa, most commonly the gastrocnemio-semimembranosus bursa. This bursa is unique in that it communicates with the knee joint, unlike other periarticular bursae, via an opening in the joint capsule posterior to the medial femoral condyle. Many have theorized that this opening creates a valve-like mechanism in the presence of effusion that contributes to the formation of these cysts in adults. Popliteal cysts rarely manifest alone and are most often found in conjunction with other intra-articular pathologies and inflammatory conditions, such as osteoarthritis, meniscus tears, and rheumatoid arthritis. In children, popliteal cysts are only occasionally associated with these conditions and are more often an incidental finding discovered during a routine physical examination. Popliteal cysts may present as either a chronically persistent or relapsing condition or as an acute and dramatic condition that can occur in the case of cyst rupture presenting as pseudothrombophlebitis. Ultrasound and magnetic resonance imaging have proven to be consistent and accurate in the confirmation of popliteal cysts, with magnetic resonance imaging becoming the modern imaging modality of choice. This review discusses the anatomy and etiology of popliteal cysts, describes the common clinical presentations, reviews the differential diagnoses, and provides guidance for proper diagnostic imaging. It also provides a comparison of current conservative, minimally invasive, and invasive treatment options, along with a discussion of results. Postoperative rehabilitation depends largely on the condition associated with the popliteal cyst.