Popliteal cyst is a common peri-knee cyst, also known as a Baker's cyst. With the current development of popliteal cysts, the pathogenesis is mainly due to increased pressure in the knee joint caused by various reasons, leading to a fluid-filled sac that can form behind the knee as a result of enlargement of the gastrocnemius-semimembranosus bursa. The current diagnostic methods include X-ray computed, ultrasound, and magnetic resonance. Among them, magnetic resonance imaging is considered the gold standard for the diagnosis of popliteal cysts. There are various treatments, including conservative treatment, traditional surgical resection and arthroscopic surgery. In recent years, the focus of the treatment of popliteal cysts has gradually shifted from the simple removal of cysts to arthroscopic treatment of intra-articular lesions and the treatment of joint-cyst communication, and achieved a good effect. However, there are still controversies about the most effective treatment, and the best surgery method is still uncertained. It is hoped that high quality prospective studies will be able to directly compare different surgery methods, so as to select the best treatment for popliteal cyst. This article reviews past literature research and describes in detail the epidemiology, pathological mechanism, clinical manifestations and signs, auxiliary examination, diagnosis and differential diagnosis and clinical treatment of popliteal cysts. Different diagnosis methods and treatment methods are compared and summarized to provide basis for clinical diagnosis and treatment.
Arthroscopy ; Bursa, Synovial ; Humans ; Knee Joint ; Popliteal Cyst ; diagnosis ; therapy ; Prospective Studies

OBJECTIVE: To compare the clinical efficacy of total arthroscopic surgery and traditional surgery for popliteal cyst. METHODS: From August 2014 to July 2017, 60 cases of popliteal cyst were treated with total arthroscopy or traditional surgery respectively. In total arthroscopy group, there were 30 patients including 7 males and 23 females with an average age of (55.81±8.53) years old; the duration of the disease was (3.52±1.12) years;according to Rauschning-Lingdgren grading, 7 cases were grade I, 19 cases were grade II, 4 cases were grade III. In traditional surgical group, there were 30 patients including 5 males and 25 females with an average age of (57.93±9.84) years old; the duration of the disease was (3.48±1.34) years; according to Rauschning-Lingdgren grading, 5 cases were grade I, 21 cases were grade II, 4 cases were grade III. Preoperative symptoms involved such as arthralgia and swelling after knee joint and limited mobility. MRI confirmed a popliteal cyst. Arthroscopic surgery and traditional surgical was used respectively. Incision length, operation time, average stay, total hospital cost and Lysholm score of two groups were compared. RESULTS: In the total arthroscopic group, 1 case suffered from nerve injury, and all cases' incision healed well. In the traditional surgical group, there was 1 case of incision infection, 2 cases of poor healing, 1 case of nerve injury and 1 case of recurrence. All 60 cases were followed up for 6 to 30 months with an average of (13.3±6.5) months. After operation, the symptoms of knee joint arthralgia and swelling, discomfort were significantly improved in the two groups. There were statistically significant differences in incision length, operation time, average stay, total hospitalcost and Lysholm score 6 months after surgery(<0.05). CONCLUSIONS The total arthroscopic resection of popliteal cyst, via anterior approach to having a knee joint cavity exploration and treatment of meniscus and bursa, while combined with posteromedial approach for cyst excision would promise a minimal surgery and less pain for patients. Patients will have a rapider recovery, lower recurrence rate and less complication. The total arthroscopic resection easy to accepting for the patient and having a better clinical curative effect is obviously superior to the traditional surgery.
Aged ; Arthroscopy ; Bursa, Synovial ; Female ; Humans ; Knee Joint ; Male ; Middle Aged ; Neoplasm Recurrence, Local ; Popliteal Cyst ; Treatment Outcome

The authors present two cases in which the ruptured popliteal (Baker's) cysts remained undetected and were diagnosed only during an isotope investigation. The aim was to describe a specific imaging sign, the “arch sign”, that is indicative of ruptured Baker's cysts. In both cases, the whole-body imaging was performed 2 hours after injection of 706.7 MBq of Tc-99m-MDP. Single-photon emission computed tomography (SPECT) imaging was performed to localize an accumulation of the radiopharmaceutical. An analysis of literature was performed to connect these cases with previously reported data and to detect the pathognomonic radio image sign of ruptured popliteal cysts. The arch-shaped distribution of the radiopharmaceutical below the knee joints was seen already on the whole-body bone scan image in both cases. An anterior view of SPECT MIP images showed the arched accumulation of the Tc-99m-MDP bone tracer along the postero-medial aspect of the right calf secondary to synovial fluid leak from a ruptured Baker's cyst. The similar arthroscintigrams were published since 1971 without recognizing this sign as pathognomonic. Tc-99m-MDP bone scanning is sensitive for a Baker's cyst with synovial effusion, and distribution of a radiopharmaceutical in the medial posterior calf in a shape of an arch, the arch sign, may serve as an indicator of a ruptured popliteal cyst.
Knee Joint ; Popliteal Cyst ; Synovial Fluid ; Tomography, Emission-Computed ; Tomography, Emission-Computed, Single-Photon

BACKGROUND: To describe the clinical and magnetic resonance imaging findings of ganglion cysts with effusion in the flexor hallucis longus tendon sheath around the hallux to evaluate their origin. METHODS: Patients with recurrent or painful ganglion cysts around the hallux with effusion in the flexor hallucis longus tendon sheath who underwent surgical treatment at St. Vincent's Hospital from February 2007 to August 2016 were investigated. Surgical indication was a painful or recurrent mass caused by the cystic lesions. Those without effusion of the flexor hallucis longus tendon sheath were excluded. We assessed the clinical and magnetic resonance imaging findings. RESULTS: Magnetic resonance imaging findings in all patients showed several ganglion cysts around the hallux and large fluid accumulations within the flexor hallucis longus tendon sheath. Regarding the location, six ganglion cysts were on the dorsomedial aspect, one on the plantar medial aspect, seven on the plantar lateral aspect, and one in the toe pulp. Ten patients showed joint effusions in both the metatarsophalangeal and interphalangeal joints, two in the metatarsophalangeal joints, and three in the interphalangeal joints. There were communication stalks with a tail shape or abutment between ganglion cysts with surrounding joint effusions. Intraoperatively, connections between ganglion cysts, the synovial cyst of the flexor hallucis longus tendon sheath, and surrounding joints were seen. CONCLUSIONS: Synovial fluid accumulation in the metatarsophalangeal or interphalangeal joint supplies the synovial cyst of the flexor hallucis longus tendon sheath and subsequently ganglion cysts in the hallux. In clinical practice, the surgeon should carefully check surrounding joints with tendon sheaths to prevent recurrence of the ganglion cysts around the hallux.
Equipment and Supplies ; Ganglion Cysts* ; Hallux* ; Humans ; Joints ; Magnetic Resonance Imaging ; Metatarsophalangeal Joint ; Recurrence ; Synovial Cyst ; Synovial Fluid ; Tail ; Tendons* ; Toes

Intraspinal synovial cysts are rare but they are being documented with increasing frequency due to improvements in radiological imaging. However, hemorrhage into synovial cysts is uncommon, and affected patients may present with acute onset radiculopathy. This type of hemorrhage is known to result from rupture of fragile neoangiogenic vessels in the cyst wall, due to a traumatic event or anticoagulant therapy. Here, the authors present a rare case of hemorrhagic lumbar synovial cyst caused by spinal instability after microscopic discectomy. To the best of the authors’ knowledge, this is the first report of hemorrhagic lumbar synovial cyst caused by spinal instability following microscopic discectomy in the absence of a traumatic event or anticoagulant therapy. We discuss the pathophysiological mechanism of this uncommon entity and provide a review of the literature.
Diskectomy* ; Hemorrhage ; Humans ; Radiculopathy ; Rupture ; Synovial Cyst*

Lumbar intraspinal synovial cysts are included in the difference diagnosis of lumbar radiculopathy. Developing imaging modalities has result in increased reporting about these lesions. However, the case of bilateral new lumbar intraspinal synovial cysts after laminectomy has been rarely reported. We report of a rare case with bilateral lumbar intraspinal synovial cysts after laminectomy, requiring surgical excision.
Diagnosis ; Epidural Space ; Laminectomy ; Lumbar Vertebrae ; Radiculopathy ; Synovial Cyst*

STUDY DESIGN: This was a retrospective study. PURPOSE: To study the surgical outcome of synovial cysts of the lumbar spine through posterior laminectomy in combination with transpedicular screw fixation. OVERVIEW OF LITERATURE: Synovial cysts of the lumbar spine contribute significantly to narrowing of the spinal canal and lateral thecal sac and nerve root compression. Cysts form as a result of arthrotic disruption of the facet joint, leading to degenerative spondylolisthesis in up to 40% of patients. METHODS: Retrospective data from 6 patients, treated during the period of March 2007 to February 2011, were analyzed. All preoperative and postoperative manifestations, extension/flexion radiographs, magnetic resonance imaging, and computed tomography records were reviewed. All underwent surgery for synovial cysts with excision and decompression combined with posterior fixation. The result of surgery was evaluated with Macnab's classification. An excellent or good outcome was considered as satisfactory. Japanese Orthopedic Association Scale was used for evaluation of back pain. RESULTS: All patients included in this study had excellent outcomes as regarding to improvement of all preoperative manifestations and returning to normal daily activities. Only 2 cases developed postoperative transient cerebro-spinal fluid leak and were treated conservatively and improved during the follow up period. CONCLUSIONS: Although this study included a small number of cases and we could not have statistically significant results, the good outcome of decompression of synovial cysts combined with posterior fixation and fusion encouraged us to recommend this approach for patients with juxtafacet synovial cysts.
Asian Continental Ancestry Group ; Back Pain ; Classification ; Decompression ; Follow-Up Studies ; Humans ; Laminectomy ; Magnetic Resonance Imaging ; Orthopedics ; Radiculopathy ; Retrospective Studies ; Spinal Canal ; Spine ; Spondylolisthesis ; Synovial Cyst* ; Zygapophyseal Joint

STUDY DESIGN: Descriptions of technical strategies to overcome pitfalls associated with early learning periods in biportal endoscopic spinal surgery (BESS). PURPOSE: To introduce BESS for lumbar spinal diseases (LSDs) and to inform certain challenges to be overcome in mastering the technique. OVERVIEW OF LITERATURE: BESS has shown superior benefits including excellent magnification, a wider range of view by dynamic handling of an endoscope and instruments. Clinical reports, however, have not yet been very revealing for its new introduction into minimally invasive spine surgery. METHODS: To evaluate the learning curve for BESS, the procedures for various LSDs by one surgeon were analyzed in the view of shortening of the operating times and reduction of complications. Reviewing of recorded procedures helped in finding the reasons and the implemented solutions. RESULTS: The 68 cases included 25 for lumbar disc herniation (LDH), 3 for revision for recurred LDH, 39 for lumbar spinal stenosis (LSS) and 1 for synovial cyst. The operation time for the total cases averaged 83.7±33.6 minutes. According to diagnosis, it was 68.2±23.7 minutes for LDH. After the 14th case of LDH, it was nearly constant and close to the average time. One level of LSS needed 110.4±34.4 minutes. Prolonged operation times even in some later cases of LSS were mainly from struggling against blurred vision due to epidural bleeding. There were 7 cases of complications (10.3%) including 2 cases of dural tear, 1 case of root injury, and 4 cases of incomplete decompression on postoperative magnetic resonance imaging. There was no case of symptomatic hematoma or wound infection. CONCLUSIONS: BESS seemed to have a relatively short learning curve period. The overall complication rate in early learning period was 10.3%. These could be avoided by magnified regional views on an endoscope and a clear surgical field by controlling epidural bleeding.
Decompression ; Diagnosis ; Endoscopes ; Hematoma ; Hemorrhage ; Learning Curve* ; Learning* ; Lysergic Acid Diethylamide ; Magnetic Resonance Imaging ; Spinal Diseases ; Spinal Stenosis ; Spine ; Synovial Cyst ; Tears ; Wound Infection

Facet joint synovial cysts are usually associated with osteoarthritis of the adjacent facet joint and/or spondylolisthesis. In between the conservative and operative ends of the treatment spectrum lie minimally invasive techniques such as cyst rupture using epiduroscopy. In this report, we describe an 82-year-old male patient presenting with low back pain radiating to his lower left extremity and associated paresthesia. Magnetic resonance imaging of the lumbar spine revealed a synovial cyst at left L4/5 facet joint. Using epiduroscopy, the cyst was mechanically ruptured by popping it with the tip of the scope. The patient remained symptom-free at his successive visits until 12 months after the procedure, and was opened for desired follow up.
Aged, 80 and over ; Extremities ; Follow-Up Studies ; Humans ; Low Back Pain ; Magnetic Resonance Imaging ; Male ; Osteoarthritis ; Paresthesia ; Rupture ; Spine ; Spondylolisthesis ; Synovial Cyst ; Zygapophyseal Joint*

Spinal cord compressing syndrome due to synovial cyst (SC) of the thoracolumbar spine is a rare clinical condition. In this report we aim to heighten awareness of the thoracolumbar facet synovial cyst as a possible cause of thoracic myelopathy. The SC was removed thoroughly by laminectomy. The patient had an excellent recovery. The etiological and therapeutic aspects are discussed.
Humans ; Laminectomy ; Paraparesis* ; Spinal Cord ; Spinal Cord Diseases ; Spine ; Synovial Cyst*