March 15, 2020
treatment option for bakers cyst cover

Treatment Options for Bakers Cyst

Bakers or popliteal cysts represent an extrusion of synovial fluid into a false cavity. This most commonly occurs between the medial head of the gastrocnemius and semimembranosus muscles and communicate with articular joint space. They are associated with intra-articular conditions such as osteoarthritis, meniscus tear, and rheumatoid arthritis. Typical presentation is vague posterior knee pain with or without soft tissue mass or swelling. Diagnosis is made with ultrasound or MRI [1]. These are notoriously stubborn to treat.
Ultrasound of bakers cyst

Figure 1. Example of ultrasound of a bakers cyst (adopted from semanticscholar.org)

Ultrasound guided aspiration with corticosteroid injection. Corticosteroid injections are generally considered first line therapy. Acebes et al also found that intra-articular injections decreased the size of the bakers cyst at 4 weeks [2]. The addition of ultrasound provides easy visualization of the fluid collection and needle guidance for aspiration and injection. Bandinelli showed that injecting directly into the cyst under ultrasound guidance was superior to injecting into the joint space [3]. Smith et al demonstrated significant decreases in pain and improved function with ultrasound guided aspiration, fenestration and corticosteroid injection [6]. Re-aspiration rate was 12.9% in this study. Koroglu et al had similar findings and also demonstrated that decrease in size of baker’s cyst correlated with degree of improvement in symptoms [4].

ultrasound guidance aspiration of bakers cyst

Figure 2. Ultrasound image of aspiration of a bakers cyst (adopted from youtube.com)

Sclerotherapy. There are several case series using sclerotherapy with dextrose to shrink the size of the cyst. This is level 4 evidence and requires more thorough investigation to demonstrate the utility [5].

Arthroscopy. Open excision is associated with high recurrence rates so surgical management revolves around an arthroscopic approach. In some cases, treatment is primarily directed toward intra-articular etiology such as meniscus or cartilage injuries. Indication for treating the cyst directly is usually failure of conservative therapy. Some surgeons will debridge the “one way valve” to allow open communication of the bakers cyst with the rest of the joint space. Alternatively, they may also attempt to close the communication between the cyst and the joint space. Cystectomy represents another option. Most of these treatment options are limited to case studies and there are no clear guidelines for surgical decision making [7].

Arthroscopic view of bakers cyst

Image 3. Arthroscopic view of a bakers cyst (adopted from azisks.com)

References

[1] Herman, Alyssa M., and John M. Marzo. “Popliteal cysts: a current review.” Orthopedics 37.8 (2014): e678-e684.
[2] Acebes JC, Sánchez-Pernaute O, Díaz-Oca A, Herrero-Beaumont G. Ultrasonographic assessment of Baker’s cysts after intraarticular corticosteroid injection in knee osteoarthritis. J Clin Ultrasound. 2006; 34:113- 117.
[3] Bandinelli F, Fedi R, Generini S, et al. Longitudinal ultrasound and clinical follow-up of Baker’s cysts injection with steroids in knee osteoarthritis. Clin Rheumatol. 2012; 31:727- 731.
[4] Köroglu M, Callıoglu M, Eris HN, et al. Ultrasound guided percutaneous treatment and follow-up of Baker’s cyst in knee osteoarthritis. Eur J Radiol. 2012; 81:3466-3471.
[5] Centeno CJ, Schultz J, Freeman M. Sclerotherapy of Baker’s cyst with imaging confirmation of resolution. Pain Physician. 2008; 11:257-261.
[6] Smith, Marvin K., et al. “Treatment of popliteal (Baker) cysts with ultrasound-guided aspiration, fenestration, and injection: long-term follow-up.” Sports health 7.5 (2015): 409-414.
[7] Zhou, Xiao-nan, et al. “Surgical treatment of popliteal cyst: a systematic review and meta-analysis.” Journal of orthopaedic surgery and research 11.1 (2016): 22.