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.

Enhanced Surgical Outcomes of Popliteal Cyst Excision: A Retrospective Study Comparing Arthroscopic Debridement with and without Methylene Blue Injection.

BACKGROUND This retrospective study of 42 patients with popliteal cysts (or Baker cysts) aimed to compare the effects on duration and outcomes of arthroscopic surgical debridement with and without the use of cyst injection with methylene blue (MB). MATERIAL AND METHODS Medical records of patients who underwent conventional arthroscopic surgery (n=20) or arthroscopic surgery after MB injection (n=22) for popliteal cysts between 2018 and 2021 were reviewed. The MB group underwent arthroscopic popliteal cystectomy with MB as the marker, and the control group underwent conventional arthroscopic popliteal cystectomy. Surgical time of cyst resection, postoperative bruising extent, complication rate, and cyst recurrence rate of the 2 groups were compared. RESULTS The MB group had a faster surgical cyst removal time (16.5±1.5 min) than the control group (24.5±1.6 min; P<0.05). The MB group had less postoperative bruising (1 case, 4.5%) than the control group (5 cases, 25%; P<0.05). The surgical results were similar in both groups, with a Lysholm score of 87.23±1.80 in the MB group and 87.23±1.62 (P>0.05) in the control group. CONCLUSIONS This study showed that preoperative injection of MB for popliteal cysts before arthroscopic debridement improved cyst localization and ease and accuracy of surgery and reduced operative time, adjacent tissue damage, postoperative complications, and recurrence rate.

Arthroscopic Treatment of Popliteal Cyst Through the Posterior Portal: A Comprehensive Clinical Study.

BACKGROUND A popliteal cyst, often perceived as benign, poses potential harm and symptoms. This study focused on arthroscopic treatment through the posterior knee portal at our medical center, aiming to assess its efficacy, safety, and long-term outcomes compared to traditional methods. MATERIAL AND METHODS A retrospective analysis of 20 patients (9 males and 11 females) with symptomatic popliteal cysts (January 2020 to December 2022) undergoing arthroscopic treatment via the posterior knee portal was conducted. Data on demographics, clinical presentation, preoperative imaging, surgical techniques, intraoperative findings, and postoperative Rauschning and Lindgren scores were collected and analyzed. RESULTS With a mean follow-up of 13.6 months (range: 12 to 36 months), all patients had associated intra-articular lesions and were treated. Degenerative cartilage damage was most common (65.0% of cases). The Rauschning and Lindgren score significantly improved after surgery (P<0.05), with no recurrence evident on MRI in any patients. CONCLUSIONS Arthroscopic treatment through the posterior knee portal has good potential for popliteal cyst management. This minimally invasive approach offers benefits such as direct visualization, precise cyst excision, and concurrent treatment of intra-articular pathologies.

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 therapeutic effects of arthroscopic popliteal cyst internal drainage and capsular wall resection].

OBJECTIVE: To investigate efficacy between arthroscopic popliteal cyst drainage and arthroscopic popliteal cyst resection. METHODS: From January 2013 to June 2021, 54 patients with popliteal cyst (Rausching-Lindgren gradeⅠto Ⅲ) were treated with arthroscopic surgery. There were 24 males and 30 females. The age ranged from 44 to 72 years old, with a mean of (62.67±6.08) years old. The course of the disease ranged from 1 to 72 months, with a mean of(15±14) months. Twenty-four patients (group A) were underwent arthroscopic internal drainage of popliteal cyst. Thirty patients (group B) were underwent arthroscopic resection of popliteal cyst. Preoperative main symptoms included knee pain, swelling, walking pain, popliteal swelling, popliteal mass and so on. After 1, 3, 6 months and 1, 2 years of surgery, routine outpatient follow-up was conducted to observe and compare the surgical time, bleeding volume, preoperative and postoperative visual analog scale (VAS), knee Lysholm score, and complications between two groups. RESULTS: All incisions healed at one stage after operation. All 54 patients were followed up, and the duration ranged from 6 months to 2 years, with an average of (13.89±4.29) months. There was no intraoperative vascular or nerve injury. Operation time and intraoperative blood loss of the two groups:group A of (62.08±9.55) min and (8.00±1.69) ml, group B of (69.50±6.99) min and (8.70±2.00) ml. Popliteal pain, swelling, limitation of flexion and extension were significantly relieved after operation. VAS before and one month after operation between two groups:group A of 5.38±1.21 and 2.63±0.71, group B of 5.60±1.26 and 2.80±0.81. Lysholm scores of knee joint before and 6 months after operation:group A of 62.59±4.99 and 89.74±2.90, group B of 63.87±3.23 and 89.02±2.35. Knee joint function improved significantly in both groups. In group A, 4 cases had popliteal cyst at 3 months after operation, and 2 cases had small isolated cyst at 1 year after operation. There was no recurrence of cyst in group B. CONCLUSION: The results between two arthroscopic treatments of popliteal cyst are satisfactory, and there is no significant difference in the amount of blood loss, safety, postoperative pain VAS score and knee function recovery. It is suggested that arthroscopic resection of the cyst wall should be performed when the technique is mature, especially for large cysts and septal cysts.

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.

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.

Arthroscopic cystectomy for Baker's cysts with and without one-way valve lesions: incidence of one-way valve lesion, associated pathologies, and clinical outcomes.

INTRODUCTION: A one-way valve lesion plays an important role in the formation of Baker's cysts and serves as an important landmark for accessing these cysts during arthroscopic surgery. This study aimed to investigate the incidence of one-way valve lesions and their effect on clinical outcomes in patients who underwent arthroscopic cystectomy for Baker's cysts. MATERIALS AND METHODS: Patients who underwent arthroscopic cystectomy for Baker's cysts between June 2005 and November 2017 were retrospectively reviewed. Patient demographic characteristics, radiologic/arthroscopic findings (presence of one-way valve lesions, concurrent chondral and meniscal lesions, and cyst wall thickness), and clinical outcomes (clinical recurrence rate, Lysholm score, and complications) at the 2-year follow-up were evaluated. Subgroup analysis was performed to compare clinical outcomes between patients with and without one-way valve lesions. RESULTS: Thirty patients (mean age, 57.4 ± 9.4 years) were included in this study. One-way valve lesions were surgically documented in 11 patients (36.7%). Ten patients (33.3%) had chondral lesions with an International Cartilage Repair Society grade ≥ 3, and 23 patients (76.7%) had concurrent chondral and meniscal lesions. At the 2-year follow-up, none of the patients had experienced clinical recurrence; the mean Lysholm score was 76.3 ± 17.5 (48-100). Three patients reported persistent pain, while two reported numbness or paresthesia. Subgroup analysis showed no significant differences in clinical recurrence rates, Lysholm scores, and complication rates between the groups. CONCLUSIONS: The incidence of one-way valve lesions during arthroscopic cystectomy for Baker's cysts was lower than that previously reported. Arthroscopic cystectomy showed good clinical results in patients with and without these lesions.

An Effective Surgical Strategy for Anteromedial Osteoarthritis of the Knee with Simultaneous Popliteal Cysts Drainage.

Unicompartmental knee arthroplasty (UKA) is an established treatment option for anteromedial osteoarthritis, and popliteal cysts are a common finding in the knee among patients with chronic osteoarthritis pain. The two are so closely related that popliteal cysts are commonly discovered during the unicompartmental knee arthroplasty preoperative examination. However, only a few reports exist on the management and outcome of popliteal cysts in the patients receiving UKA for knee osteoarthritis (OA) and popliteal cysts. As such, it is crucial to evaluate different treatment strategies and their management of popliteal cysts. In this paper, we evaluate a surgical strategy for patients with knee anteromedial osteoarthritis and symptomatic popliteal cysts. These patients were treated with UKA and internal drainage of the popliteal cyst. The results shown here, spanning 1-year post-operation follow-up, demonstrated that UKA and internal drainage is an effective surgical protocol for treating anteromedial osteoarthritis with symptomatic popliteal cysts.

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.

Differential evolution and cost-maps for needle path planning in Baker's cyst aspiration.

PURPOSE: The Baker's cysts appear within the popliteal fossa along with the progression of degenerative changes. Removal of its contents through aspiration is often a necessary complement to treatment at various stages of the development of gonarthritis. METHODS: The paper presented a procedure for needle automatic needle path planning in cyst aspiration in transverse plane. The method was based on optimization and used a custom objective function, which utilized cost maps obtained from preprocessed, segmented images of the knee. The optimization was carried out with Differential Evolution. Furthermore, a preliminary sensitivity analysis was carried out. The obtained paths were compared to the reference paths proposed by an experienced surgeon. RESULTS: The procedure was tested on 165 numerical simulations. In all of the obtained paths, the needle successfully avoided crucial objects, such as veins, arteries and nerves. Furthermore, the overall travel distance in the joint was also minimized. When compared to the reference from the surgeon, 90% of the paths were almost the same or only slightly different. Furthermore, the remaining 10% of the generated paths were viable but different. CONCLUSION: Based on the obtained results, the proposed solution could be a viable solution for planning the aspiration of Baker's cyst.

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.

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.

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.

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.

The fate of Baker's cysts at mid-term follow-up after total knee arthroplasty.

AIMS: We report the natural course of Baker's cysts following total knee arthroplasty (TKA) at short- and mid-term follow-up. METHODS: In this prospective case series, 105 TKA patients were included. All patients who received surgery had a diagnosis of primary osteoarthritis and had preoperatively presented with a Baker's cyst. Sonography and MRI were performed to evaluate the existence and the gross size of the cyst before TKA, and sonography was repeated at a mean follow-up time of 1.0 years (0.8 to 1.3; short-term) and 4.9 years (4.0 to 5.6; mid-term) after TKA. Symptoms potentially attributable to the Baker's cyst were recorded at each assessment. RESULTS: At the one-year follow-up analysis, 102 patients were available. Of those, 91 patients were available for the 4.9-year assessment (with an 86.7% follow-up rate (91/105)). At the short- and mid-term follow-up, a Baker's cyst was still present in 87 (85.3%) and 30 (33.0%) patients, respectively. Of those patients who retained a Baker's cyst at the short-term follow-up, 31 patients (35.6%) had popliteal symptoms. Of those patients who continued to have a Baker's cyst at the mid-term follow-up, 17 patients (56.7%) were still symptomatic. The mean preoperative cyst size was 14.5 cm2 (13.1 to 15.8). At the short- and mid-term follow-up, the mean cyst size was 9.7 cm2 (8.3 to 11.0) and 10.4 cm2 (9.8 to 11.4), respectively. A significant association was found between the size of the cyst at peroperatively and the probability of resolution, with lesions smaller than the median having an 83.7% (36/43) probability of resolution, and larger lesions having a 52.1% (25/48) probability of resolution (p < 0.001). At the mid-term follow-up, no association between cyst size and popliteal symptoms was found. CONCLUSION: At a mean follow-up of 4.9 years (4.0 to 5.6) after TKA, the majority (67.0%, 61/91) of the Baker's cysts that were present preoperatively had disappeared. The probability of cyst resolution was dependent on the size of the Baker's cyst at baseline, with an 83.7% (36/43) probability of resolution for smaller cysts and 52.1% (25/48) probability for larger cysts. Cite this article: Bone Joint J. 2020;102-B(1):132-136.

Clinical Outcomes after Mini-Open Excision of Popliteal Cysts.

PURPOSE: The purpose of the study was to investigate clinical outcomes following a mini-open posterior technique. METHODS: Patients who received mini-open popliteal cyst excisions between April 1999 and April 2010 were identified. Charts were retrospectively reviewed for postoperative complications, cyst recurrence, previous aspiration, re-operation, intraoperative findings, cyst size, comorbidities, and co-surgeries. Visual Analogue Pain Scale and Rauschning's symptomatic knee criteria were collected prospectively to assess functional outcomes. RESULTS: Twenty-two legs in 21 patients were included in the study [males: 12 (57%); females: 9 (43%); age: 48.23 ± 11.74 years; BMI: 26.7 ± 4.54 kg/m2; follow-up: 4.55 ± 3.01 years]. Average cyst size was 4.16 ± 1.64 cm and were all located in the posteromedial aspect of the leg. All 22 cases had associated intra-articular pathology based on MRI, physical examination, and arthroscopy. Complications after cyst excision included: paresthesia in the distribution of the saphenous nerve (3/22, 14%), keloid formation (1/22, 4%), joint effusion requiring aspiration (1/22, 4%), and one recurrence requiring cystectomy 10 years later (4%). All incidences of paresthesia resolved. Mean visual analog pain score decreased by 6 points (p < 0.001) and Rauschning and Lindgren score decreased by two categories, from a 2.6 (category 2-3) preoperatively to 0.6 (category 0-1) postoperatively (p < 0.001). CONCLUSION: Mini-open popliteal cyst excision is a safe and effective technique for refractory popliteal cysts in patients who desire a decrease in pain, an increase range of motion, and improved function in knee flexion and extension. Further studies are needed to evaluate the clinical outcomes of patients over a longer duration as our one patient with a 10-year follow-up required a repeat procedure.