Biomedical subjects

Keiichi Murata

Publications and source records attributed to Keiichi Murata.

5 recordsLinked to original sources

PubMed2006

Anatomic study of arborization patterns of the ulnar artery in Guyon's canal.

PURPOSE: To show variations in arborization patterns of the ulnar artery in Guyon's canal and to investigate the relationship between the hypothenar muscles and the ulnar artery. METHODS: Thirty-five embalmed cadaveric hands were dissected and the existence and course of the superficial and deep palmar branches of the ulnar artery and the site of feeding branches to the hypothenar muscles were recorded. The anatomic relationship between the ulnar artery and the hypothenar muscle variations also was investigated. RESULTS: Four arborization patterns were identified. In type 1UA (n = 17 hands), an artery accompanying the deep branch of the ulnar nerve (AADBUN) formed a deep palmar arch (DPA). In type 2UA (n = 11 hands) the AADBUN continued to the feeding artery of the abductor digiti minimi and the distal deep palmar branch of the ulnar artery (DDPBUA) branched off distally. This arterial structure formed a DPA. In type 3UA (n = 6 hands) both the AADBUN and DDPBUA formed DPAs. In type 4UA(n = 1 hand), the AADBUN continued to the feeding artery of the abductor digiti minimi with no DDPBUA and therefore no DPA. A dorsal perforating artery of the ulnar artery also was found in 4 hands. This branch came from the AADBUN at the level of the distal edge of the pisiform and merged with the dorsal carpal arterial arch. We also investigated the relationship between the structural pattern of the hiatus for the deep branch of the ulnar nerve and ulnar artery variation but found no association. The most common pattern observed was a type 1 hiatus with a type 1UA arborization pattern. CONCLUSIONS: Our study confirmed considerable variations in the arborization pattern of the ulnar artery in Guyon's canal. To avoid injury to the arterial branches during surgery in this region care must be taken with respect to variations of the ulnar artery in Guyon's canal.

Cadaver↗

PubMed2006

Post-traumatic big toe reconstruction using free flaps.

The big toe is of great importance for good stability and gait, but few reports have documented reconstruction of big toe defects. In this study, seven male patients, aged 17 to 59 years at surgery (average: 35 years), were treated for big toe defects. The metatarsophalangeal (MTP) joints of the big toe were intact in all patients. Five patients were treated with free peroneal flaps (including one perforator flap), and two with free scapular flaps; flap sizes ranged from 9 x 4 to 24 x 6 cm. Follow-up periods ranged from 10 to 29 months, (average: 16.6 months). The iliac was used as the grafted bone in four patients and the scapula in one. Six flaps survived completely, and bone unions were achieved within 3 months. One flap became partially necrotic due to arterial thrombosis. All patients returned to their original jobs, and the cosmetic appearances of all toes were acceptable.

Adolescent↗

PubMed2004

Anatomic study of variations of hypothenar muscles and arborization patterns of the ulnar nerve in the hand.

PURPOSE: To show the variations in the hypothenar muscles and the arborization patterns of the ulnar nerve and to investigate the relationship between the hypothenar muscles and the ulnar nerve. METHODS: We performed an anatomic study of 35 hands from embalmed cadavers. After dissecting the ulnar side of the hand we recorded the number of hypothenar muscles and their variations, the site of the hiatus for the deep branch of the ulnar nerve, and the branching patterns of the ulnar nerve in each hand. We then investigated the relationship between the variations in the hypothenar muscles and the arborization patterns of the ulnar nerve. RESULTS: The abductor digiti minimi (ADM) had 1 belly in 6 hands, 2 bellies in 28 hands, and 3 bellies in 1 hand. The flexor digiti minimi brevis was absent in 8 hands, had 1 belly in 24 hands, and had 2 bellies in 3 hands. The opponens digiti minimi had 2 layers of origin and the deep branch of the ulnar nerve passed between these 2 layers in all hands. We classified the structural patterns of the hiatus into 3 types, the arborization patterns of the ulnar nerve into 5 types, and the branching patterns of the motor branch to the ADM into 4 types according to their morphologic characteristics. We found variations of the arborization pattern in which the deep branch originated from the ulnar trunk of the ulnar nerve distal to bifurcation in 3 hands, a communicating branch was present between the 2 sensory branches to the fingers in 3 hands, and the ulnar sensory branch pierced the ADM in 2 hands. CONCLUSIONS: We confirmed that the anatomic relationship between the ulnar nerve and the hypothenar muscle is complex and that the formation of the hiatus varies. This knowledge can assist the surgeon in the diagnosis and treatment of conditions associated with the ulnar aspect of the hand.

Aged↗

PubMed2003

Causes of ulnar tunnel syndrome: a retrospective study of 31 subjects.

PURPOSE: The purposes of this study were to determine the distribution of causes and sites of nerve compression in the ulnar tunnel (Guyon's canal), and investigate the relationship between ulnar tunnel syndrome (UTS) and other conditions associated with it. METHODS: We performed a retrospective review of 31 patients diagnosed with and treated for UTS to determine the most common cause of compression and the sites of compression, systemic illnesses associated with UTS, and postoperative results. RESULTS: The cause of ulnar nerve compression was idiopathic in 14, trauma in 8, a thrombosis in 2, proliferation of synovium in 2, a prominent hook of the hamate in 1, a schwannoma in 1, postoperative swelling in 1, an aberrant fibrous band in 1, and a ganglion in 1. The sites of compression were classified into 3 zones. Twenty-eight cases had compression in zone 1, 6 in zone 2, and 19 in zone 3. Seventeen cases (55%) had compression in more than 1 zone. Twenty-two cases (71%) were associated with carpal tunnel syndrome (CTS). Twelve (86%) of the 14 idiopathic UTS cases were associated with CTS. The relationship between idiopathic UTS and CTS was not statistically significant. Six cases were associated with diabetes mellitus. CONCLUSIONS: The most common cause of UTS in our series was idiopathic. Most idiopathic UTS cases were associated with CTS. The clinical symptoms of UTS improved after surgery in all cases. Therefore because of the presence of multiple compression sites of the ulnar nerve in the hand, for UTS patients we believe that the release of Guyon's canal and/or the pisohamate tunnel is an effective way not only to relieve symptoms but also to determine the real cause of compression.

Adolescent↗

PubMed2002

Vascularized composite tissue transfers or open fractures with massive soft-tissue defects in the lower extremities.

From 1982 to 1998, we treated 39 patients with type IIIB and IIIC fractures in the lower extremities by vascularized composite tissue transfers. Thirty-four of the lesions affected the lower leg, and 5 the foot and ankle. The peroneal flap was used in 25 cases, the latissimus dorsi musculocutaneous flap in 12, the scapula flap in 1, and the gracilis muscle flap in 1. In cases with a peroneal flap transfer, 18 cases used osteocutaneous flap with a fibula. Postoperative circulatory disturbances resulted in revision surgery in 9 patients. Eventually, grafting was successful in 37 patients. In patients with a lower leg reconstruction, additional bone grafting was performed in 7 of 16 patients with cutaneous or musculocutaneous flap transfers. No patient with osteocutaneous flap transfers required an additional bone grafting. The mean periods between injury and time to bone union were 11.7 months in patients with cutaneous flap transfers, and 7.5 months in patients with osteocutaneous flap transfers.

Adolescent↗