Ultrasonography findings in knee osteoarthritis: a prospective observational cross-sectional study of 100 patients

Worldwide, knee osteoarthritis (KOA) accounts for 2.2% of total years lived with disability. There is a low correlation between joint tissue damage and pain intensity. Periarticular structures may be involved and cannot be identified in X-rays. To describe the main ultrasonography (USG) changes in symptomatic patients with primary KOA; to correlate the number of USG findings with KOA severity assessed by Kellgren and Lawrence (K&L) radiological scores, with pain intensity measured by a visual analogue scale (VAS) and with functioning scores assessed with the Timed up and go test (TUG) and Western Ontario and McMaster Universities (WOMAC) questionnaire. 100 patients with primary symptomatic KOA were assessed with X-ray and USG. Quantitative and qualitative analyses were evaluated in a systematic manner. The most frequent findings were joint effusion, pes anserinus bursitis, quadriceps tendon enthesopathy, popliteal cyst, iliotibial band tendinitis and patellar tendinitis. Pearson’s correlation analysis demonstrated a significant moderate positive association between VAS scores and the number of USG findings (r = 0.36; p < 0.0001). The number of USG findings was different between K&L grades I and III (p = 0.041), I and IV (p < 0.001), and II and IV (p = 0.001, analysis of variance with Bonferroni correction). There was significant association between number of USG findings and TUG (r = 0.18; p = 0.014) and WOMAC scores for pain (r = 0.16; p < 0.029) and physical function domains (r = 0.16; p < 0.028). The most frequent USG finding was joint effusion. Periarticular structures should be explored as potential sources of pain and disability.

Ruptured Popliteal Cysts Mimicking Deep Vein Thrombosis in Well-functioning Total Knee Replacements: Report of Two Cases and Review of Literature

Introduction: Implant wear and loosening with eluding metal/polythene debris are commonly implicated in the occurrence of Baker’s cysts in post-operative total knee replacement (TKR) patients, who present with post-operative pain and swelling, mimicking deep venous thrombosis. However, we present two symptomatic cases presenting with ruptured Baker’s cysts post-TKRs, with no evidence of implant loosening or wear. Cases Report: The 1st patient was a 55-year-old male, who underwent TKR for Grade 4 bilateral knee osteoarthritis and presented with acute onset of pain and swelling over the left popliteal fossa, which progressed to involve the calf. Radiographs showed no sign of infection or loosening, and venous color Doppler and magnetic resonance imaging (MRI) showed a hy-poechoic collection in the intermuscular plane at the upper part of popliteal fossa. Histological examination of the aspirated fluid showed mixed features of cystic fluid and a resolving hematoma. There was complete resolution of the 4 months with rest and graduated physiotherapy. The 2nd patient was a 51-year-old female who developed the cystic swelling 2 years after the surgery, and the ultrasound showed hypoechoic echoes in a Baker’s cyst-like collection. Cytological findings were suggestive of hemorrhagic nature of the aspirate, without any evi-dence of polyethylene debris, and the cultures were sterile. She became asymptomatic over 4 weeks with conservative management; the swelling resolved after 3 months. Conclusion: Majority of the cases in literature show implant loosening as cause of popliteal cysts after TKRs, however present cases highlight alternative mechanisms, and there are good chances of self-resolution of cysts with conservative treatment in such cases. Keywords: Knee replacement, Baker’s cyst, deep vein thrombosis, ruptured popliteal cyst.

POPLITEAL CYSTIC SCHWANNOMA MIMICKING BAKER CYST – AN UNUSUAL CASE PRESENTATION – CASE REPORT

Introduction: Schwannoma is the most common tumor of peripheral nerves. They are usually solitary, encapsulated, homogenous slow growing masses, sometimes associated with pain and paresthesia.We present a case of schwannoma in an unusual location. Case presentation: A 16 year old boy presented to surgical OPD with a slow growing left popliteal swelling for 6 months and neuralgia for 1 month. The swelling decreasing on knee exion. Based on clinical suspicion patient was operated for popliteal cyst. Intraoperatively there was close association with nerve and it was difcult to dissect from nerve. So it was thought of being a nerve tumor. Surgical excision was done. Histopathological examination revealed it to be Cystic Schwannoma. Discussion: Schwannoma is the most common benign neoplasm of peripheral nerves. Cystic degeneration and repeated hemorrhages (10%) can occur sometimes. There are two types of tissues in Schwannoma – Antoni A and Antoni B.Schwannoma varies from 2-20 cm in diameter. It is not localized to any specic area; it can occur anywhere along peripheral nervous system in neck, mediastinum, retroperitoneum, pelvis, upper extremities. It is extremely unusual in lower limb of which tibial nerve is uncommon site. Conclusion: Diagnosis of schwannoma originating from lower extremity peripheral nerves may be delayed because it can be misdiagnosed as Baker's Cyst or the symptoms of the patient can be thought as a result of lumbar disc herniation.Thorough clinical examination and investigations, conrms the diagnosis, as management is different for both.

Baker’s cyst in children: conservative management versus surgical excision according to clinical and imaging criteria

Background Pediatric patients rarely exhibit Baker’s cysts. This study was conducted on 15 cases (9 males, 6 females) presented with Baker (popliteal) cyst in the last 2 years (from September 2017 to September 2019). The mean age was 8.5 years. The aim of this study was to present our experience in management of these cases based on clinical and imaging criteria. Plain x-ray and knee ultrasonography were routinely done for all cases. If the size of the cyst was less than or equal to 3 cm by ultrasonography, with no or minimal pain, the patients were managed conservatively and were scheduled to followed up visits after 3 months, 6 months, and after 12 months for clinical assessment of symptoms and sonographic size of the cyst. Surgical excision of the Baker’s cyst was considered if the size of the cyst was more than 3 cm with persistent of pain. Results Seven cases had cysts less than 3 cm by ultrasonography and were managed conservatively. In five out of these seven cases, the cysts disappeared with no recurrence within the first year of follow-up. In two cases, the cysts increased in size with increase in pain. These two cases were subjected to surgical excision after 1 year of follow-up. The remaining eight cases had cysts more than 3 cm and were managed by surgical excision. Out of the ten cases which were managed by surgical excision, recurrence occurred in 3 cases within the first post-operative year (after 4 months, 7 months, and 8 months) consecutively. Conclusions The management of Baker’s cysts in children is debatable, with no definite protocol. In this current study, we conclude that surgical excision of large Baker’s cysts (more than 3 cm) with persistent symptoms is crucial providing meticulous dissection without rupture of the cyst and proper closure of the pedicle which connects the cyst with the knee joint, while conservative management and follow-up is effective in small Baker’s cysts (less than 3 cm) with no recurrence.

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.