The hand consists of five sesamoids. Two of them are present at the metacarpophalangeal (MCP) joint of the thumb. Fracture of the sesamoid bones of the thumb is a rare injury and the literature on the radial side is seldom reported. We reported a case of a patient with a fracture of the radial sesamoid at the MCP joint of the thumb in order to increase attention regarding this type of injuries. A 44-year-old male, high level gymnastic trainer, was helping one of his athletes during an exercise while he reported a hyperextension trauma to the MCP joint of the right thumb. One week after trauma, he presented to the hand surgeon complaining of a painful thumb at the MCP joint level on its palmar aspect. Standard A-P and lateral X-rays revealed a fracture of the radial sesamoid and the fracture was treated with a splint for 3 weeks. He was able to resumed his entire work 6 weeks after the injury. The sesamoid fractures is an indicator of the magnitude of the hyperextension injury and sometimes associated with tears of the volar plate ligament of the MCP joint. And a failure to recognize the ligament injury may lead to a long-term hyperextension instability on pinching.
Fractures, Bone ; diagnostic imaging ; Humans ; Metacarpophalangeal Joint ; injuries ; Radiography ; Sesamoid Bones ; Thumb ; injuries

Accessory ossicles are normal variants that are frequently seen but often overlooked or misdiagnosed. Commonly seen at the foot and ankle, they may be mistaken for fracture fragments or loose bodies, or not be recognised as a cause of the patient's symptoms. This pictorial essay aimed to review commonly encountered accessory ossicles of the foot and ankle by highlighting anatomic landmarks and associated pathologic processes through the use of both basic and advanced imaging modalities, in an effort to increase awareness of these clinical entities.
Adult ; Aged, 80 and over ; Ankle Joint ; diagnostic imaging ; Female ; Foot ; diagnostic imaging ; Fractures, Bone ; diagnostic imaging ; Humans ; Magnetic Resonance Imaging ; Male ; Sesamoid Bones ; diagnostic imaging ; Tomography, X-Ray Computed

OBJECTIVETo introduce diagnosis and treatment of the metacarpophalangeal joint (MPJ) locking caused by sesamoid turned-over dislocation of the thumb.

METHODSFive cases with metacarpophalangeal joint locking were involved in the study, male 4 and female 1. The average age was 35 years old(ranging from 18 to 47 years). All the patients received manual reduction under local anaesthesia. But only three were successful, others patients were reduced by operation. Metacarpophalangeal joint locking caused by sesamoid turned-over dislocation with the volar plate and the short flexor muscle of the thumb tendon were reveded. The metacarpophalangeal joint locking was released after reduction of sesamoid turned-over dislocation of the thumb.

RESULTSThe mean follow-up time was 15 months (3-34 months). The mean range of MPJ flexion was 45 degrees (35 degrees - 60 degrees). The signs for pain and swelling were released. Satisfactory thumb opposition can be seen.

CONCLUSIONIt was one of the important reasons of the metacarpophalangeal joint locking caused by sesamoid turned-over dislocation of the thumb.

Adolescent ; Adult ; Female ; Follow-Up Studies ; Humans ; Joint Dislocations ; diagnosis ; diagnostic imaging ; surgery ; therapy ; Male ; Metacarpophalangeal Joint ; diagnostic imaging ; injuries ; Middle Aged ; Sesamoid Bones ; diagnostic imaging ; injuries ; Thumb ; diagnostic imaging ; injuries ; Tomography, X-Ray Computed

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

OBJECTIVE: To investigate a method to distinguish avulsion fracture from sesamoid, accessory bone, and permanent osteoepiphyte. METHODS: Fourteen cases of suspicious avulsion fractures of articular portion of tubular bones were reviewed. Direct/indirect signs and the injury mechanism of avulsion fractures were analyzed and compared with permanent osteoepiphyte, sesamoid and accessory bones for their morphological characteristics. RESULTS: There are two cases of permanent osteoepiphytes, three cases of sesamoids, and three cases of accessory bones. These cases were characterized by smooth edges, contiguous bony cortex, without swelling of the surrounding soft tissue or obvious image changes after consecutive radiography. CONCLUSION It is fundamental in image analysis to distinguish avulsion fracture from physiological small osteoepiphyte, sesamoid bone, and aberrant accessory bone.
Adolescent ; Adult ; Ankle Injuries/diagnostic imaging* ; Child ; Diagnosis, Differential ; Epiphyses/diagnostic imaging* ; Epiphyses, Slipped/diagnostic imaging* ; Female ; Forensic Medicine ; Fractures, Bone/diagnostic imaging* ; Humans ; Knee Injuries/diagnostic imaging* ; Male ; Middle Aged ; Retrospective Studies ; Sesamoid Bones/diagnostic imaging* ; Shoulder Fractures/diagnostic imaging* ; Tomography, X-Ray Computed ; Young Adult