An intraneural ganglion cyst of the ulnar nerve at the wrist: a case report and literature review.

BACKGROUND: Intraneural ganglion cysts of the ulnar nerve at the wrist are rare and poorly understood. We report a case of an intraneural ganglion cyst at the level of the wrist.Case presentation: A 48-year-old man presented with the complaints of weakness for 6 months and serious aggravation for 1 month in his right hand. After examinations, including ultrasound, the patient was diagnosed with an intraneural ganglion cyst. Intraoperatively, with exposure of the ulnar nerve, we found that the intraneural ganglion cyst was at the level of Guyon's canal and extended approximately 6 cm proximally. Postoperatively, sensation of the fingers was normal, but atrophy of his muscles and limited straightening of his ring and little fingers were similar to those preoperatively. CONCLUSIONS: Diagnosis of an intraneural cyst before surgery is mostly based on ultrasound and magnetic resonance imaging. Transection of the articular branch is an important measure to prevent recurrence of this cyst. If the ulnar nerve is compressed and causes symptoms, nerve decompression, including removal/aspiration of the cyst, and sometimes external neurolysis of the nerve, are necessary to relieve the symptoms and allow regeneration of the nerve. However, these should be performed without damaging the nerve fascicles.

Vascularized Small-Bone Transfers for Fracture Nonunion and Bony Defects.

Vascularized small-bone grafting is an efficient and often necessary surgical approach for nonunion or necrosis of several bones in particular sites of the body, including scaphoid, lunate, distal ulna, and clavicle. The medial femoral condyle is an excellent graft source that can be used in treating scaphoid, ulna, clavicle, or lower-extremity bone defects, including nonunion. Vascularized bone grafting to the small bones, particularly involving reconstruction of damaged cartilage surfaces, should enhance subchondral vascular supply and help prevent cartilage regeneration. Vascularized osteoperiosteal and corticoperiosteal flaps are useful for treating nonunion of long bones.

Vascularized Small-Bone Transfers for Fracture Nonunion and Bony Defects.

Vascularized small-bone grafting is an efficient and often necessary surgical approach for nonunion or necrosis of several bones in particular sites of the body, including scaphoid, lunate, distal ulna, and clavicle. The medial femoral condyle is an excellent graft source that can be used in treating scaphoid, ulna, clavicle, or lower-extremity bone defects, including nonunion. Vascularized bone grafting to the small bones, particularly involving reconstruction of damaged cartilage surfaces, should enhance subchondral vascular supply and help prevent cartilage regeneration. Vascularized osteoperiosteal and corticoperiosteal flaps are useful for treating nonunion of long bones.

In vivo length and changes of ligaments stabilizing the thumb carpometacarpal joint.

PURPOSE: To investigate the lengths and changes of selected ligaments stabilizing the thumb carpometacarpal (CMC) joint during thumb motion in vivo. METHODS: We obtained serial computed tomography scans of the thumb CMC joints of 6 healthy volunteers during thumb flexion, abduction, and opposition. We reconstructed the 3-dimensional structures of the bones of the thumb CMC joint using customized software and modeled the paths of fibers of 5 principal ligaments--deep anterior oblique (beak), dorsoradial, posterior oblique, intermetacarpal, and dorsal intermetacarpal--at each of the CMC joint positions studied. We estimated the virtual lengths of these ligaments in neutral position, flexion, abduction, and opposition of the CMC joint by measuring the distances between the origin and the insertion of individual ligaments, and statistically analyzed the length changes. RESULTS: The estimated length of the CMC joint ligaments underwent significant changes during thumb motion in vivo. Thumb flexion led to the greatest changes in ligament lengths. During flexion, all the ligaments lengthened significantly (p < .05 or p < .01), except for the beak ligament, which shortened significantly (p < .001). The lengths of the ligaments changed similarly during thumb abduction and opposition, except for the dorsoradial ligament. In both motions, the posterior oblique and dorsal intermetacarpal ligaments lengthened and the beak ligament shortened significantly (p < .05 or p < .01). During the 3 thumb motions, the beak ligament underwent marked shortening, while the other measured ligaments lengthened to varied extent. CONCLUSIONS: The estimated lengths of principal ligaments stabilizing the CMC joint change substantially during thumb motions in vivo. Thumb flexion causes the greatest changes of the ligament lengths; abduction and opposition result in similar changes in the ligament lengths. The beak ligaments shorten while the other ligaments lengthen. This in vivo study suggests that thumb motions expose the CMC joint ligaments to different tensions at these thumb positions, and that the ligaments are under lower tension during thumb opposition and abduction than during flexion.