Koichi Tada

A classification for congenital limb malformation

The classification for congenital limb malformations adopted by the American Society for Surgery of the Hand, the International Federation of Societies for Surgery of the Hand, and the International Society of Prosthetics and Orthotics is presented. This method groups similar patterns of deficiencies according to the parts that have been primarily affected by certain embryological failures, whether the insult involves a total part (skeletal and soft tissue) or only the dermomyofascial structures. The main categories of this classification are (I) failure of formation of parts, (II) failure of differentiation (separation) of parts, (III) duplication, (IV) overgrowth, (V) undergrowth, (VI) congenital constriction band syndrome, and (VII) generalized skeletal abnormalities. The rationale and method of use of the classification are discussed. This method has been tested and used in a variety of centers and has been found to be properly conceived and practical.

Canal diameter, anteroposterior compression ratio, and spondylotic myelopathy of the cervical spine.

Nine patients with cervical spondylotic myelopathy, diagnosed during life, were subjected to detailed clinicopathologic study. The degree of cord destruction was in good correlation with the ratio of the anteroposterior diameter to the transverse diameter, designated as an anteroposterior compression ratio. Within the factors responsible for decrease in the ratio, developmental narrowing of the spinal canal was the most significant, and multiplicity of spondylotic protrusion less so. The former resulted in an extensive demyelination of the posterolateral funiculus and infarction of the gray matter. Recurrent trauma proved to cause distinct manifestations and cord pathology. Clinicopathologic correlations were also examined from the neurologic findings at the terminal stage.

Cervical Myelopathy Secondary to Multiple Spondylotic Protrusions: A Clinicopathologic Study

Five patients with severe cervical spondylotic myelopathy were followed clinically until their deaths, and their neurologic deficits were repeatedly documented. In the terminal phase, these patients exhibited abnormal postures, severe muscle wasting, and the inability to stand and walk. Sensory loss varied and was most severe peripherally. Necropsy on all 5 patients disclosed multiple levels of spinal cord compression as measured by computing an anteroposterior compression ratio. This compression was associated with extrusive destruction of both gray and white matter, and ascending and descending demyelination could be traced above and below the most damaged segment.

Human meniscus cell: characterization of the primary culture and use for tissue engineering.

Human meniscus cells from 47 surgically excised menisci were grown in primary culture. Cell proliferation and morphologic features were evaluated in three different culture media. Human meniscus cells showed three distinguishable cell types in monolayer culture: elongated fibroblastlike cells, polygonal cells, and small round chondrocytelike cells. These cells proliferated in Dulbecco’s modified Eagle’s medium, but by Day 7, elongated fibroblastlike cells became predominant. Cells did not proliferate in Ham’s nutrient mixture-F-12. In a mixture of Ham’s nutrient mixture-F-12 and Dulbecco’s modified Eagle’s medium, cells proliferated, maintaining their morphologic features and their ability to express messenger ribonucleic acids for aggrecan and Types I, II, and III collagen. Hyaluronan enhanced cellular proliferation without altering morphologic features or chondroitin sulfate production. Cultured human meniscus cells attached to a porous collagen sponge after cell seeding. Gene transfer was successful and an introduced gene was expressed by the cells, indicating that human meniscus cells can undergo gene manipulation. The finding that cells collected from small surgical specimens of human meniscus could be cultured, propagated, and seeded onto a collagen scaffold holds promise for the development of a cell-based, tissue engineered collagen meniscus.

Ossified Posterior Longitudinal Ligament: A Clinicopathologic Study

The clinical features of 166 patients with ossification of the posterior longitudinal ligament are reported. Symptoms of cervical myelopathy develop and include difficulty walking and sensory and motor disturbances. Roentgenograms disclose dense ossification posterior to the vertebral bodies, and symtoms are most often observed when the ossification occupies more than 60% of the saggital diameter of the cervical canal. Posterior decompression is the most effective surgical treatment. Two patients with ossification of the posterior longitudinal ligament and ankylosing spinal hypertosis expired and necropsy was performed. The histologic features of the spine and spinal cord are described.

Duplication of the thumb. A retrospective review of two hundred and thirty-seven cases.

Over a twenty-two-year period, 237 patients (261 hands) with duplication of the thumb were seen in the Hand Clinic of Osaka University Hospital. Two groups were identified: Group A, 141 patients without previous surgical treatment, and Group B, ninety-six patients with residual deformity despite previous surgical treatment. Using a modification of Wassels classification, seven types of deformity were defined. In Group A these types were identified on the basis of the observed duplications of bone and soft tissue. In all but ten of the Group-B patients preoperative roentgenograms were not available and the type of deformity had to be deduced from the residual duplicated bone, the surgical scar, and the residual deformity. Surgery, performed on 193 hands (125 in Group A and sixty-eight in Group B), attempted to restore normal anatomical relationships. The results could be evaluated in 130 hands according to the range of motion, joint stability, and alignment of the remaining thumb after an average follow-up of 35.0 months. According to the rating system described, the results were rated as good in 75.5 per cent, fair in 20.2 per cent, and poor in 4.3 per cent of the ninety-four hands in Group-A patients who were followed. In the thirty-six hands of Group-B patients who could be followed, the preoperative and postoperative scores were compared. Thirteen were not improved while the other twenty-three, sixteen improved from fair to good and seven improved from poor to fair, to give a good result in 63.9 per cent of the Group-B patients who were followed. The results in these 130 Group-A and B hands emphasize the importance of providing muscle balance and, in young patients, of performing an arthroplasty of the interphalangeal or metacarpophalangeal joint when indicated, although arthrodesis was indicated as a salvage operation for Group-B patients who were more than fifteen years old.

Early microsurgical reconstruction in birth palsy.

Most patients with birth palsy can be expected to recover spontaneously. But in some patients the recovery is unsatisfactory and the functional results are disappointing. One possible way to improve the prognosis for such patients is early surgical nerve reconstruction. In six infants, exploration of the brachial plexus was carried out at about six months after delivery, when there were no signs of recovery in shoulder and elbow joint movements. Preoperative metrizamide myelography, computerized tomography with intrathecal metrizamide (CT myelography), and axon reflex test (histamine test) were followed by intraoperative electrophysiologic examinations of root sensory evoked potential (SEP), nerve action potential (NAP), and evoked muscle response (M-response). Microsurgical nerve repair was performed on the basis of intraoperative diagnosis. Metrizamide myelography showed 13% false-positive root avulsion. Reliability of the histamine test was 80%. The intraoperative electro-diagnosis is essential for understanding the actual condition of the brachial plexus lesion and obtaining better results from microsurgical reconstruction in birth palsy. The surgical results, with an average follow-up evaluation of two years and four months, have been encouraging enough to continue this diagnostic and therapeutic program, though its superiority to natural recovery has not yet been clarified.

Nerve repairs for traumatic brachial plexus palsy with root avulsion

Thirty-six patients with traumatic brachial plexus lesions and root avulsions were treated surgically between 1972 and 1986 and were followed for more than 24 months (average, 42.6 months). Neurotization of the musculocutaneous nerve with intercostal nerves or the spinal accessory nerve resulted in satisfactory elbow flexion in 21 of the 33 cases (64%). Combined nerve repairs (i.e., intercostal and spinal accessory neurotization of the terminal branch of the brachial plexus in combination with nerve grafts from the upper spinal nerves of the brachial plexus) created a useful function in at least one functional level of the upper limb for 11 of the 15 cases so treated. Nerve repairs resulted in stability of the shoulder and elbow function controllable with a sensible hand for patients with root avulsion injury of the brachial plexus.

Etiologic factors of myelopathy. A radiographic evaluation of the aging changes in the cervical spine.

The radiographic characteristics of the cervical spine among older individuals were investigated in 100 normal subjects and compared with those of younger subjects. The cervical spine of the older subjects displayed narrowing of intervertebral discs and osteophytoses (posterior osteophytes as well as anterior osteophytes) at the levels of C5-6 and C6-7, where the range of motion was decreased. Such degenerative changes resulted in vertebrolisthesis, especially retrolisthesis, predominantly at the levels of C3-4 and C4-5, where intervertebral disc space was well maintained and mobility was well preserved. Both static and dynamic anteroposterior canal diameter decreased with age. Throughout the aging process the dynamic canal became much narrower than the static canal, except at C2-3. Posterior osteophytes at C5-6 or C6-7 and retrolisthesis at C3-4 or C4-5 were major levels of stenosis associated with changes in the dynamic canal. Following the same evaluation system, 20 elderly patients with cervical spondylotic myelopathy were assessed. Based on the above-noted characteristics of the aging process, patients with myelopathy had smaller static and dynamic canal measurements than normal subjects. The development of cervical myelopathy, however, was not always based on critical static or dynamic canal stenosis (10% in this series) and might involve other factors.

Cervical Spondylotic Myelopathy in the Aged Patient: A Radiographic Evaluation of the Aging Changes in the Cervical Spine and Etiologic Factors of Myelopathy

Cervical spondylotic myelopathy among older individuals was investigated radiographically in 42 patients over age 60 years, and compared with those of younger patients. The cervical spine in the aged patients displayed dynamic canal stenosis in addition to static canal stenosis based on the aging process. Myelography and computed tomography-myelography showed multisegmental lesions (average: 3.0 lesions), that contributed to the various clinical features of myelopathy. The upper disc levels of C3-4 and C4-5 had a tendency to be involved in the aged patients, and the spinal cords were extensively compressed as compared with the younger patients. Disc protrusion, posterior osteophyte, and retrolisthesis, in addition to ligamentous entrapments were the primary etiologic factors of myelopathy. Morphologically, the high prevalence of cord atrophy was seen on computed tomography-myelography in the aged patients. This indicated severe pathologic changes in the cervical spinal cord, and its prognosis was considered to be poor.