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Kazuteru Doi

Publications and source records attributed to Kazuteru Doi.

13 recordsLinked to original sources

Ulnar variance and the role of joint levelling procedure for Kienböck's disease.

Forty patients with Kienböck's disease were reviewed to determine the relationship between ulnar variance and the development of Kienböck's disease in a Japanese cohort. The joint levelling procedures designed to correct ulnar variance were evaluated in 11 patients after a mean of 9.7 years following surgery. The mean ulnar variance was 0.50+/-1.67 in patients with Kienböck's disease and 0.56+/-1.76 in a control group. The onset of wrist symptoms in a younger age group was noticed after sports injuries, whereas older patients had no distinct history of trauma. Joint levelling procedures produced good clinical results, but carpal height ratio, Stahl's index and radioscaphoid angle were not improved, as evidenced radiographically. Our study suggests that in a Japanese cohort ulnar minus variance is not an important factor in the aetiology of Kienböck's disease. Although joint levelling procedures improved the clinical results, they did not reverse lunate collapse or carpal alignment.

Adolescent↗

A benefit of the volar approach for wrist arthroscopy.

We reviewed 230 cases of wrist arthroscopy using a volar approach and evaluated its advantage in various wrist disorders. In general, a dorsal approach has been preferred in wrist arthroscopy. The volar approach has been avoided because of the presence of significant structures, such as radial and ulnar arteries, their venae comitantes, median and ulnar nerves, and flexor tendons. However, we can access the wrist joint securely using the volar approach through the tendon sheath of the flexor carpi radialis. Through this approach, we can adequately visualize the dorsal rim fragment of the intra-articular fracture of the distal radius, dorsal synovial proliferation of the rheumatoid wrist, and volar segment tear of the scapholunate and lunotriquetral interosseous ligaments. We had no complications with wrist arthroscopy using the volar approach in 230 patients. The volar approach for wrist arthroscopy is a valuable procedure to evaluate and treat various wrist disorders.

Adult↗

Arthroscopic assessment of the volar region of the scapholunate interosseous ligament through a volar portal.

PURPOSE: The volar region of the scapholunate interosseous ligament is one of the key structures that maintains scapholunate alignment. It is, however, difficult to evaluate this ligament using standard diagnostic procedures, including the arthroscopy through a dorsal portal. We have performed arthroscopic evaluation of this ligament through a volar portal. METHODS: Skin incision was made at just radial of the flexor carpi radialis tendon and the portal was opened through the tendon sheath. RESULTS: The volar approach enabled us to directly observe the extent of the tear of the volar region of scapholunate interosseous ligament. A shaver is inserted through the dorsal portal, and debridement can be performed by using the volar portal vein. We have not had any complications using volar portal. CONCLUSION: Volar approach is a feasible and safe procedure to evaluate and treat the volar region of the scapholunate interosseous ligament.

Arthroscopy↗

Recalcitrant posttraumatic nonunion of the humerus: 23 patients reconstructed with vascularized bone graft.

We treated 23 patients with recalcitrant posttraumatic humeral shaft nonunion with vascularized bone grafts (fibula 10, femur 10 and scapula 3). 21/23 patients healed primarily. Venous thrombosis in the graft necessitated postoperative thrombectomy in 2 patients. Complications at the donor site were trivial. We used a vascularized fibular graft in patients with a large bone defect and with poor intrinsic stability of the nonunion site and a corticoperiosteal femoral graft in atrophic nonunion without a substantial bone defect. The scapula graft is easy to transfer to the surgical neck of the humerus on its pedicle.

Adult↗

Significance of venous anastomosis in fingertip replantation.

Adequate venous outflow is the most important factor for successful fingertip replantation. The authors have attempted venous anastomosis in all cases of fingertip replantation to overcome postoperative congestion. In this article, the significance of venous repair for fingertip replantation is described from the authors' results of 64 complete fingertip amputations in 55 consecutive patients, which were replanted from January of 1996 to June of 2001. The overall survival rate was 86 percent. Of the 44 replantations in zone I, 37 survived, and the success rate was 84 percent. Of the 20 replantations in zone II, 18 survived, and the success rate was 90 percent. Venous anastomosis was attempted in all cases, but it was possible in 39 zone I and in all zone II replantations. For arterial repair, vein grafts were necessary in 17 of the 44 zone I and in one of the 20 zone II replantations; for venous repair, they were necessary in six zone I replantations and one zone II replantation. Postoperative vascular complications occurred in 15 replantations. There were five cases of arterial thrombosis and 10 cases of venous congestion. Venous congestion occurred in nine zone I and one zone II replantations. In five of these 10 replantations, venous anastomosis was not possible. In another five replantations, venous outflow was established at the time of surgery, but occlusion occurred subsequently. Except for the five failures resulting from arterial thrombosis, successful venous repair was possible in 49 of 59 replantations (83 percent). Despite the demand for skillful microsurgical technique and longer operation time, the authors' results using venous anastomosis in successful fingertip replantations are encouraging. By performing venous anastomosis, external bleeding can be avoided and a higher survival rate can be achieved. Venous anastomosis for fingertip replantation is a reliable and worthwhile procedure.

Adolescent↗

Scaphoid fracture in the young athlete--therapeutic outcome of internal fixation using the Herbert screw.

BACKGROUND: A fractured scaphoid is a common disabling injury occurring in contact sports. This study was designed to evaluate the therapeutic outcome of Herbert screw fixation for scaphoid fracture in young athletes. METHODS: Thirty athletes with 30 scaphoid fractures were treated. According to the Herbert classification, 10 were classified as acute fracture (group I), 6 as fibrous union (group II) and 14 as pseudoarthrosis (group III). Twenty scaphoid non-unions were due to missed diagnosis or unsuccessful immobilisation. RESULTS: Bony union was evident at an average of 9.2, 8.0 and 11.9 weeks postoperatively in groups I, II and III, respectively, and times for returning to sports were 10.7, 14.0 and 22.9 weeks. The clinical outcome assessed using the Mayo wrist score was excellent in groups I (97.5 points) and II (93.3) and good in group III (85.4). CONCLUSION: Early definitive diagnosis and treatment can allow early return to sports in young athletes. The Herbert screw technique produces an excellent clinical result for scaphoid fracture.

Adolescent↗

Basic science behind functioning free muscle transplantation.

Free muscle transfer is now a feasible procedure in several fields of reconstructive surgery. In this article, basic science behind clinical free muscle transfer, including essential aspects like donor muscle selection (type of blood supply, architecture of fibers, fiber length, and muscle volume), donor nerve selection, placement and routing of muscle, tension of muscle at suturing, postoperative monitoring of muscle circulation, postoperative reinnervation, and rehabilitation are discussed in detail.

Facial Paralysis↗

A part of the ulnar nerve as an alternative donor nerve for functioning free muscle transfer: a case report.

A patient with no active elbow flexion because of poliomyelitis-like syndrome underwent functioning free muscle transfer for elbow flexion reconstruction in which a part of the ulnar nerve was used as a donor motor nerve. Fourteen months after surgery the patient had achieved 120 degrees of active elbow flexion against gravity without functional deficit of the donor ulnar nerve. A part of the ulnar nerve can be used as an alternative donor motor nerve for reconstruction of chronic C5-C6 (or C5-7) brachial plexus injury.

Adolescent↗

Transtibial amputation with plantar flap for congenital deficiency of the tibia.

Disarticulation of the knee has been the preferred treatment for the severe type (Type Ia and Type Ib classification of Jones et al) of congenital deficiency of the tibia because of marked flexion contracture of the knee and loss of quadriceps function. In such cases, the disarticulated stump is often small and poorly covered by soft tissues because of dysplastic femoral condyles and calf muscles. Therefore, stump complications after disarticulation may prevent early aggressive walking exercises and delay independent ambulation. To overcome this problem, a greater weightbearing surface was created by a transtibial amputation with a short stump of the fibula using the flexed knee. By this method, the distal femoral condyle and the anterior surface of the fibula were used for weightbearing. In addition, coverage of the new weightbearing area by a neurovascular pedicled sensate plantar flap provided a more tolerable weightbearing site. The purpose of the current study was to report a 5-year-old boy with bilateral congenital total deficiency of both tibias, who was treated using this technique. The patient was ambulating independently 15 weeks after surgery. A transtibial amputation with a plantar flap is an alternative procedure to knee disarticulation for the severe type of congenital deficiency of the tibia.

Amputation, Surgical↗

Cervical nerve root avulsion in brachial plexus injuries: magnetic resonance imaging classification and comparison with myelography and computerized tomography myelography.

OBJECT: The authors describe a new magnetic resonance (MR) imaging technique to demonstrate the status of the cervical nerve roots involved in brachial plexus injury. They discuss the accuracy and reproducibility of a MR imaging-derived classification for diagnosis of nerve root avulsion compared with those of myelography combined with computerized tomography (CT) myelography. METHODS: The overlapping coronal-oblique slice MR imaging procedure was performed in 35 patients with traumatic brachial plexus injury and 10 healthy individuals. The results were retrospectively evaluated and classified into four major categories (normal rootlet, rootlet injuries, avulsion, and meningocele) after confirming the diagnosis by surgical exploration with or without spinal evoked potential (EP) measurements and by referring to myelography and CT myelography findings. The reliability and reproducibility of the MR imaging-based classification was prospectively assessed by eight independent observers, and its diagnostic accuracy was compared with that of traditional myelography/CT myelography classification, correlated with surgical and spinal EP findings in another 50 cervical roots in 10 patients with traumatic brachial plexus injury. CONCLUSIONS: In the retrospective study in which MR imaging and myelography/CT myelography findings involving 175 cervical roots in 35 patients were compared, the sensitivity of detection of the cervical nerve root avulsion was the same (92.9%) with both modalities. In the prospective study, interobserver reliability and intraobserver reproducibility showed that there was no statistically significant difference between MR imaging and myelography/CT myelography and that their accuracy for detecting cervical root avulsion was the same as that in the retrospective study. The overlapping coronal-oblique slice MR imaging technique is a reliable and reproducible method for detecting nerve root avulsion. The information provided by this modality enabled the authors to assess the roots of the brachial plexus and provided valuable data for helping to decide whether to proceed with exploration, nerve repair, primary reconstruction, or other imaging modalities.

Adult↗