Acrophyseal growth arrest in a long-term survivor of acute lymphoblastic leukemia

Growth arrest at the secondary growth plate, also known as the acrophysis, is a rare phenomenon with only very few known published case reports. We report on a case of formation of ghost secondary ossification centers at the acrophyses of the knee joint in a 14-year-old female, who survived early childhood acute lymphoblastic leukemia. The patient suffered from severe side effects from both disease and subsequent treatment strategies with a 10-month immobilization period as a consequence at the age of 3 years. The ghost secondary ossification centers were encountered on radiographs and MRI 10 years later, when she presented for evaluation of chronic pain in her left knee related to sports activities, due to a meniscal cyst. Awareness of this phenomenon is nevertheless important, because it seems that endochondral bone growth recovery at the acrophyses might be different from recovery in physes, because we found no concomitant sequelae of growth arrest in the metaphyses.

Synovial chondromatosis masquerading as a para-meniscal cyst of the knee

Synovial chondromatosis and parameniscal cysts are well documented pathologies around the knee joint. We present an unusual presentation of synovial chondromatosis masquerading as a parameniscal cyst of the knee. The patient was an 82-year old gentleman seen in our knee clinic with painful swelling over medial aspect of the right knee, no history of injury and with symptoms of a locked knee. Clinico-radiological features were suggestive of a binary pathology of a meniscal tear and multi-locular cyst of the knee. An arthroscopic assisted open excision of the cystic lesion allowed clinical recovery with histological confirmation of benign synovial chondromatosis. We highlight the challenges in our case with the overlap of diagnostic features of both synovial and meniscal pathology with surgical management of this patient.

A Case of Infrapatellar Fat Pad Ganglion of the Knee

Introduction: A ganglion cyst can induce symptoms around the knee and should be considered as an intra-articular mass in differential diagnosis. Case Presentation: A 22-year-old female presented with a persistent medial knee joint pain in her left knee for 2 years. There was soft tissue swelling on the anteromedial aspect of the infrapatellar region on her left knee. Lachman and McMurray tests were negative. MRI showed a multilobular cyst in the infrapatellar fat pad with T1 low intensity and T2 STIR high intensity. The cyst was not attached to either meniscus. ACL and PCL looked normal. During surgery, the cyst was found to arise from the intra-patellar fat pad and was not attached to the menisci or synovium. The cyst was completely resected. Histological findings showed a multilobular cyst with a glassy fibrous tissue wall and clear jelly-like consistency, confirming the diagnosis of a ganglion. The patient recovered asymptomatically and has been without recurrence 7 years postoperatively. Conclusion: Differential diagnoses of an infrapatellar swelling are a meniscal cyst, synovial cyst, or ganglion. Most cases of cysts around the knee generate from fluid collection through meniscal tears. A ganglion cyst is a synovium-lined structure and is common around the wrist joint, but rare in the knee joint. A ganglion cyst in the knee joint often arises from ACL or PCL, but rarely arises from the infrapatellar fat pad. A ganglion cyst is one of the differential diagnoses of parameniscal cysts around the knee. We recommended an open resection with arthroscopic examination.