Etsuhiro Nakao

The ulnocarpal stress test in the diagnosis of ulnar-sided wrist pain.

Forty-five patients with persistent ulnar-sided wrist pain and a positive ulnocarpal stress test were investigated by X-ray, arthrography, 99mTechnetium bone scanning, magnetic resonance imaging and wrist arthroscopy. Ulnar wrist pathology was positively identified in nine of 45 patients by X-ray, 18 of 37 by arthrography, 19 of 27 by bone scan, four of 33 by MRI, and in all 45 patients by arthroscopy. The final diagnosis was ulnocarpal abutment syndrome in 28 patients, traumatic triangular fibro-cartilage (TFC) tear in six, lunotriquetral (LT) ligament tear in five, TFC and LT ligament tear in one, wrist arthritis in four and cartilaginous free body in one. The ulnocarpal stress test is a useful provocative test, and a positive test suggests the presence of ulnar-sided wrist pathology. The test is sufficiently sensitive to warrant further investigation by arthroscopy.

Surgical Treatment for Chronic Radial Head Dislocation

Background : The treatment of chronic radial head dislocation remains controversial. High rates of redislocation and complications have been reported after surgery. In our view, correction of malalignment with ulnar osteotomy is the key to a good surgical result. Methods: Since 1975, twenty-two patients were treated surgically for chronic radial head dislocation at our hospital. The procedure consisted of open reduction of a dislocated radial head followed by radial and/or ulnar osteotomy, with or without reconstruction of the annular ligament or by reconstruction of the annular ligament alone. The ages of the patients ranged from four to twenty years. In 1991, we modified the surgical technique by performing an oblique ulnar osteotomy with angulation and elongation and rigid plate fixation. Bone-grafting at the osteotomy site was also performed if necessary. A cast was applied with the forearm in neutral rotation and was worn for two to four weeks. Nine patients were treated with this modified technique. Results: The mean interval between the initial injury and the reconstructive surgery was ten months. There were no serious surgical complications. Of the thirteen patients treated before 1991, four had a good reduction and seven had redislocation. Seven patients had restricted forearm rotation postoperatively. Of the nine patients treated with the modified osteotomy since 1991, seven had a good reduction. Two patients, who had had slight radial head deformity preoperatively, had subluxation postoperatively. Two patients had restricted forearm rotation. Conclusions: Since we modified our technique for ulnar osteotomy, good reduction of the radial head has been achieved without causing serious contracture. Both angulation and elongation of the ulna are required to allow the radial head to reduce.

Proximal Row Carpectomy Versus Limited Wrist Arthrodesis for Advanced Kienböck’s Disease

The outcomes in 20 patients with advanced Kienböcks disease treated by proximal row carpectomy (seven patients) or limited wrist arthrodesis (13 patients) were reviewed retrospectivey. Postoperatively, the results were more satisfactory in terms of wrist pain, the range of wrist flexion–extension, and grip strength following limited wrist arthrodesis than after proximal row carpectomy, although the differences were not statistically significant. We recommend scaphotrapeziotrapezoid arthrodesis in selected patients with advanced Kienböcks disease who have a fragmented lunate.

Surgical outcome of radial osteotomy for Kienböck's disease : minimum 10 years of follow-up

PURPOSE Long-term results of radial osteotomy for Kienböcks disease seldom are seen in the literature. The purpose of this study was to report the minimum 10-year results and to compare them with the 5-year results to determine whether the favorable intermediate-term results were maintained. METHODS Twenty-five patients who underwent radial osteotomy were followed-up for a mean period of 14.5 years. They were examined for pain, grip strength, and wrist range of motion (ROM). Through a review of clinical records, 5-year postoperative results were collected. The carpal height ratio and Ståhls index were measured and the x-rays were inspected for osteoarthritic changes. We devised an original lunate grade to evaluate radiologic improvement of the ischemic lunate. Overall results were evaluated using Cooneys wrist function score and Nakamuras scoring system for Kienböcks disease. The long-term results were compared with both the preoperative status and the 5-year results. RESULTS Pain, ROM, and grip strength were improved significantly after surgery, and the results were maintained for a long period. Carpal height ratio and Ståhls index did not show significant improvements but ischemic lunate showed certain radiologic improvements with time by the lunate grade system. Osteoarthritic changes were observed in 54% of patients at 5 years and in 73% of patients at the final follow-up evaluation, but the arthrosis generally was mild and did not affect the clinical results. Cooneys wrist function score was excellent or good in 96% of the patients, and the results with Nakamuras scoring system for Kienböcks disease were excellent or good in 68% of the patients at the final follow-up evaluation. The percentages were the same 5 years after surgery. CONCLUSIONS Radial osteotomy for Kienböcks disease is a reasonable treatment option and clinical improvement lasts for a long period of time. Although radiologic improvement was not drastic, the inner structure such as sclerotic change or bone cysts of the lunate improved with time, indicating healing of the ischemic lunate. Severe osteoarthritic change or proximal migration of the capitate can be avoided.

Distal radioulnar joint subluxation and dislocation diagnosed by standard roentgenography.

The use of standard lateral roentgenography for diagnosing distal radioulnar joint (DRUJ) subluxation and dislocation was investigated. Using a wrist support, bilateral standard lateral roentgenograms of the wrist were obtained in 42 patients with normal wrists and in 56 patients with a unilateral wrist injury. In normal wrists the difference between the radioulnar distance in the right and the left wrist did not exceed 4 mm when the difference in the pisoscaphoid distance was less than 3 mm. Of the 36 patients with wrist injury whose difference in pisoscaphoid distance was less than 3 mm, 15 had a radioulnar distance of 5 mm or more, and computed tomography (CT) confirmed DRUJ dislocation in 14. Concordance between lateral roentgenograms and CT was present in 33 of 36 patients (92%). These results demonstrate the value of a standardized technique for bilateral lateral roentgenography in diagnosing DRUJ subluxation and dislocation.

Criteria for diagnosing distal radioulnar joint subluxation by computed tomography.

Abstract Bilateral wrist computed tomography (CT) was performed in 30 patients with suspected unilateral distal radioulnar joint (DRUJ) subluxation to evaluate dynamic DRUJ CT scanning with a straight elbow. Five CT criteria for diagnosing dorsovolar subluxation were examined. Maximum active supination and pronation on a conventional scanning table yielded satisfactory rotation (mean±SD, 119°±29°) at the DRUJ, thus permitting a dynamic diagnosis of DRUJ subluxation. The radioulnar line method and the congruity method frequently yielded false positive results compared with bilateral diagnosis and were unreliable. Modifications of these two methods achieved sensitivity and specificity comparable to the epicenter method. We recommend the modified radioulnar line method for diagnosing dorsovolar subluxation using unilateral CT because of its excellent sensitivity and specificity combined with ease of technique.

Ulnar Styloid Malunion with Dislocation of the Distal Radioulnar Joint

Four patients with dorsal dislocation of the distal radioulnar joint and ulnar styloid malunion had corrective osteotomy of the ulnar styloid. Dislocation of the distal radioulnar joint was reduced in three of four patients. Subluxation persisted in the remaining patient. Wrist function improved in all patients. These results support the contention that a displaced ulnar styloid fracture with distal radioulnar joint dislocation should be reduced and internally fixed. Corrective osteotomy is recommended for malunion of the ulnar styloid associated with dislocation of the distal radioulnar joint.

Diagnostic imaging for fracture of the hook of the hamate.

We experienced 16 patients with a fracture of the hook of the hamate. The routine posteroanterior view raised the suspicion of fracture in four of 13 patients (31%), the carpal tunnel view showed the actual fractures in six of 14 patients (43%), and the supine oblique radiographic view of the wrist showed fractures in eight of ten patients (80%). Computed tomography corroborated the fracture in all eight patients (100%). Computerized tomography proved most useful for accurate diagnosis of fracture of the hook of the hamate.

Distraction Lengthening of the Forearm for Congenital and Developmental Problems

Thirty-five callus distractions of the forearm were carried out in 23 patients, who were divided into two groups according to the cause of the shortening. Eleven cases in group A had congenital dysplasia, and the 12 cases in group B had growth disturbances from tumours or infection. The mean amount of lengthening was 27 mm in group A and 25 mm in group B. The mean percentage increase in length was 35% and 17%, respectively. The mean duration of fixation was 159 days and 127 days, respectively. The Healing Index had a positive correlation with the age at surgery in group A, but not in group B. The main complication was callus deformity after the removal of a fixator, which was especially frequent in group A. To avoid complications, the aetiology of shortening and the age of the patient should be considered when deciding the surgical protocol.

Surgical treatment of congenital metacarpal synostosis of the ring and little fingers.

Fifteen hands with congenital metacarpal fusions were treated operatively by osteotomy combined either with the use of a silicone block or a distraction device. The aim of the silicone block was to separate the fused metacarpals, but it was buried in the metacarpals at follow-up, with recurrence of fusion. By the distraction technique, 13 mm of lengthening was obtained. The average length of the little metacarpal was 88% of that of the long finger metacarpal. Both methods were effective in correcting the abduction deformity of the little finger by a mean of 34°, and increasing the range of motion of the metacarpophalangeal joint to 28° of active flexion. Although the distraction method took longer than the silicone block method, the final appearance of the hand was better.