Unlike meniscal tears and chondral defects, the mucoid degeneration of the anterior cruciate ligament (ACL) is a rare cause of knee pain and there have been no case reports of mucoid degeneration of both the ACL and the posterior cruciate ligament (PCL). A 48-year-old-male patient presented with knee pain and limitation of motion. The patient's magnetic resonance imaging, arthroscopic findings, and pathologic diagnosis confirmed a clinical diagnosis of mucoid degeneration of both the ACL and the PCL. The symptoms disappeared after arthroscopic partial excision of the ACL and PCL.
Anterior Cruciate Ligament/*pathology/radiography ; Arthralgia/etiology ; Humans ; Joint Diseases/diagnosis/*pathology/radiography ; Knee Joint/*pathology/radiography ; Male ; Middle Aged ; Posterior Cruciate Ligament/*pathology/radiography

OBJECTIVETo study the application of stress X-ray of knee joint for the diagnosis ot medial collateral ligament injury.

METHODSFrom January 2008 to June 2011, 46 patients with medial collateral ligament injury were reviewed. Among the patients, 32 patients were male and 14 patients were female, ranging in age from 28 to 72 years, with an average of (49.46 +/- 22.54) years. Left knee joint injuries occurred in 22 patients, and 24 patients had injuries in right knee joint. Thirty-one patients were treated with surgical method, and 15 patients were treated with conservative method including 1 patient finally received operation after 3 months treatment with conservative method without effect. The injury side and normal side were observed by X-ray under stress and non-stress, as well as MRI. Operation was used to treat patients with medial gap markedly widen and the deep layer of medial collateral ligament injury in MRI. A line (line A) was drawn from medial condyle to lateral condyle of tibia platform. The line A was translated to the inner margin of condylus medialis femoris, which was line B. The perpendicular distance was measured, which was line C. The ration of space difference (R) was calculated by (space at stress force of injured side-space at non-stress force of injured side)/(space at stress force of normal side-space at non-stress force of normal side). The relationship between R and ligament injury type were investigated.

RESULTSThere were 17 patients with injuries of superficial lamella, 21 patients with injuries of deep lamella. Eight patients had associated injuries of articular capsule and posterior cruciate ligament. When R value was between 1.51 to 5.24, the injury of superficial ligament was found in 15 patients, actual injuries were found in 17 patients. When R value between 5.28 and 13.85, the injuries of bathypelagic ligament were found in 19 patients, actual injuries were found in 21 patients. When R value was between 15.61 and 26.25, the associated injuries of articular capsule and posterior cruciate ligament were found in 7 patients, actual injuries were found in 8 patients.

CONCLUSIONUsing the specific value as the standard of measurement can provide the quantizatily fractionation of the medial collateral ligament injury.

Adult ; Aged ; Female ; Humans ; Knee Joint ; diagnostic imaging ; pathology ; Magnetic Resonance Imaging ; methods ; Male ; Medial Collateral Ligament, Knee ; injuries ; Middle Aged ; Radiography

Ganglion cysts are more commonly associated with the anterior cruciate ligament than the posterior cruciate ligament (PCL). A literature review showed that all reported cases of ganglion cysts to date involved adults. We report a rare case of ganglion cyst in the PCL of a four-year-old boy, and discuss its aetiology, clinical presentation, imaging features and management. Ganglion cysts of the PCL may be confused with meniscal cysts arising from tears of the posterior horn of the medial meniscus on magnetic resonance (MR) imaging. Hence, the posterior horn of the medial meniscus has to be carefully evaluated to rule out a tear. MR imaging is the method of choice to confirm diagnosis, and arthroscopic resection is a safe treatment modality even in children.
Arthroscopy ; Child, Preschool ; Ganglion Cysts ; diagnosis ; surgery ; Humans ; Knee Joint ; diagnostic imaging ; Magnetic Resonance Imaging ; Male ; Posterior Cruciate Ligament ; injuries ; pathology ; Radiography

Calcium Pyrophosphate ; metabolism ; Cartilage, Articular ; metabolism ; pathology ; Chondrocalcinosis ; diagnostic imaging ; metabolism ; pathology ; surgery ; Diagnosis, Differential ; Female ; Gout ; pathology ; Humans ; Knee Joint ; diagnostic imaging ; metabolism ; pathology ; Male ; Menisci, Tibial ; metabolism ; pathology ; Middle Aged ; Osteoarthritis ; etiology ; pathology ; Radiography

Adult ; Bone Neoplasms ; diagnosis ; diagnostic imaging ; pathology ; Diagnosis, Differential ; Diaphyses ; diagnostic imaging ; pathology ; Humans ; Knee Joint ; diagnostic imaging ; pathology ; Lipoma ; diagnosis ; diagnostic imaging ; pathology ; Magnetic Resonance Imaging ; Male ; Radiography ; Tibia ; diagnostic imaging ; pathology

INTRODUCTIONThe fabella, a sesamoid bone sometimes found in the lateral head of the gastrocnemius muscle, often articulates directly with the lateral femoral condyle. This study aimed to determine the incidence of fabellae in an Asian population and to characterise the radiological features of the fabella.

METHODSElectronic radiographs and magnetic resonance imaging films of 80 consecutive patients who underwent knee arthroscopy between May 2005 and October 2009 were reviewed to determine the presence and characteristics of the fabella.

RESULTSThe incidence of fabellae was 31.25% in our study cohort. The median length, thickness, width and distance of the fabella from the lateral femoral condyle were 7.06 mm, 4.89 mm, 6.12 mm and 33.19 mm, respectively. The fabella was consistently bony and located in the lateral head of the gastrocnemius, with 52% of the fabellae having an articulating facet. Fabellae in men were found to be larger than in women, although the difference was not statistically significant. The presence of an articulating groove was associated with increased size of the fabella, but not with the distance between the fabella and its insertion onto the lateral head of the gastrocnemius.

CONCLUSIONThe incidence of fabellae in our population was lower than that in regional studies. They were consistently bony and not all had articulating grooves on the lateral femoral condyle. We found that the larger the fabella, the higher the chances of it having an articulating groove. By defining the radiological characteristics of the fabella, we provide objective parameters to help differentiate the fabella from other loose bodies or calcifications in the knee.

Adolescent ; Adult ; Arthroscopy ; Asia ; Cohort Studies ; Female ; Humans ; Incidence ; Knee Joint ; diagnostic imaging ; pathology ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Muscle, Skeletal ; diagnostic imaging ; pathology ; Radiography ; Sesamoid Bones ; diagnostic imaging ; pathology ; Sex Factors ; Young Adult

BACKGROUNDIt has been demonstrated that bone tunnel widening could appear after knee anterior cruciate ligament (ACL) reconstruction, especially for those patients whose ruptured ACL were reconstructed with semitendinosus and gracilis tendons. Many factors can influence the extent of tunnel widening. Few studies have investigated the relationship between bone tunnel widening and rehabilitation procedures. This research was carried out to find the rehabilitation procedures' influence on the tibial bone tunnel widening after ACL reconstruction.

METHODSSixty-five cases, whose ACL reconstructions were done using quadrupled semitendinosus and gracilis tendons, were divided into two groups. Group A had 33 cases, 19 men, 14 women, averaged (31.2 +/- 12.4) years old, only ACL reconstruction was done using Paessler's technique, and aggressive rehabilitation procedure was used for function recovery post operation. Group B had 32 cases, 20 men, 12 women, averaged (30.3 +/- 10.3) years old. Except for ACL reconstruction, every patient in group B accepted meniscus repair using re-fixation methods or cartilage repair using microfracture technique, conservative rehabilitation procedure was used post operation. Six months post operation, standard posterior-anterior radiographic plates were taken for each case, CorelDRAW 8.0 software was used to digitize all X-ray plates and measure the upper, middle and lower parts of the tibial tunnel. Magnification effect of X-ray plates was taken out after measurement.

RESULTSSix months after ACL reconstruction the tibial tunnel widening of the upper, middle and lower parts on both the posterior-anterior and lateral X-ray plates in Group A with aggressive rehabilitation procedure was much more serious than in Group B with conservative rehabilitation. KT-1000 knee stability measurement and clinical manifestation showed no difference between the two groups.

CONCLUSIONSRehabilitation procedure after ACL reconstruction is one of the reasons for tunnel widening. It not only can directly influence the function recovery of ACL reconstructed knee, but also perhaps indirectly influence the function recovery and long-term clinical result of the operated knee by influencing the tunnel widening.

Adult ; Anterior Cruciate Ligament ; diagnostic imaging ; surgery ; Female ; Humans ; Joint Instability ; Knee Injuries ; rehabilitation ; surgery ; Male ; Middle Aged ; Orthopedic Procedures ; Radiography ; Reconstructive Surgical Procedures ; Retrospective Studies ; Tendons ; transplantation ; Tibia ; diagnostic imaging ; pathology