Shigeru Kurimoto

Targeting Anti-Inflammatory Treatment Can Ameliorate Injury-Induced Neuropathic Pain

Tumor necrosis factor-α plays important roles in immune system development, immune response regulation, and T-cell-mediated tissue injury. The present study assessed the net value of anti-tumor necrosis factor-α treatment in terms of functional recovery and inhibition of hypersensitivity after peripheral nerve crush injury. We created a right sciatic nerve crush injury model using a Sugita aneurysm clip. Animals were separated into 3 groups: the first group received only a skin incision; the second group received nerve crush injury and intraperitoneal vehicle injection; and the third group received nerve crush injury and intraperitoneal etanercept (6 mg/kg). Etanercept treatment improved recovery of motor nerve conduction velocity, muscle weight loss, and sciatic functional index. Plantar thermal and von Frey mechanical withdrawal thresholds recovered faster in the etanercept group than in the control group. On day 7 after crush injury, the numbers of ED-1-positive cells in crushed nerves of the control and etanercept groups were increased compared to that in the sham-treated group. After 21 days, ED-1-positive cells had nearly disappeared from the etanercept group. Etanercept reduced expression of interleukin-6 and monocyte chemotactic and activating factor-1 at the crushed sciatic nerve. These findings demonstrate the utility of etanercept, in terms of both enhancing functional recovery and suppressing hypersensitivity after nerve crush. Etanercept does not impede the onset or progression of Wallerian degeneration, but optimizes the involvement of macrophages and the secretion of inflammatory mediators.

Sonography-guided Arthroscopy for Wrist Ganglion

PURPOSE To describe how to combine the complementary features of sonography and arthroscopy to make the arthroscopic resection of wrist ganglions a safer and more reliable surgery. METHODS A total of 22 patients with wrist ganglions had sonography-assisted arthroscopic resection. Sonographic visualization of ganglions, adjacent structures (ie, vessels, nerves, and tendons), and the cycling tip of the arthroscopic shaver was assessed. Arthroscopic visualization of the ganglions or ganglion stalk was also assessed. Clinical outcome measures included wrist range of motion, grip strength, and our patient-rated Hand 20 questionnaire. RESULTS Sonographic visualization of the ganglion stalk, adjacent structures, and the cycling tip of the arthroscopic shaver was possible in all 22 cases. However, ganglion stalks were visualized by arthroscopy in only 4 cases. The mean range of motion and grip strength were not significantly changed following surgery. However, the mean Hand 20 score was significantly improved from 17 to 6 at final follow-up. Ganglion recurrence was seen in 2 cases at 6 and 8 months after surgery. CONCLUSIONS Sonography-guided wrist arthroscopy provides several advantages for surgeons, including visualization of the ganglions and ganglion stalk, as well as of the arthroscopic shaver and adjacent structures such as nerves, vessels, and tendons to perform surgery safely.

Development and validation of a ten-item questionnaire with explanatory illustrations to assess upper extremity disorders: favorable effect of illustrations in the item reduction process

BackgroundThe purpose of this study is to develop a short and valid measure for upper extremity disorders and to assess the effect of attached illustrations in item reduction of a self-administered disability questionnaire while retaining psychometric properties.MethodsA validated questionnaire used to assess upper extremity disorders, the Hand20, was reduced to ten items using two item-reduction techniques. The psychometric properties of the abbreviated form, the Hand10, were evaluated on an independent sample that was used for the shortening process.ResultsValidity, reliability, and responsiveness of the Hand10 were retained in the item reduction process. It was possible that the use of explanatory illustrations attached to the Hand10 helped with its reproducibility. The illustrations for the Hand10 promoted text comprehension and motivation to answer the items. These changes resulted in high acceptability; more than 99.3% of patients, including 98.5% of elderly patients, could complete the Hand10 properly.ConclusionThe illustrations had favorable effects on the item reduction process and made it possible to retain precision of the instrument. The Hand10 is a reliable and valid instrument for individual-level applications with the advantage of being compact and broadly applicable, even in elderly individuals.

Cubital tunnel syndrome caused by amyloid elbow arthropathy in long-term hemodialysis patients: report of 4 cases.

Carpal tunnel syndrome occurs frequently in long-term hemodialysis patients. However, the literature contains few detailed reports of other nerve entrapment syndromes of the upper extremity in these patients. We encountered 4 cases in which cubital tunnel syndrome occurred in long-term hemodialysis patients. In all cases, a hypertrophic synovial mass projecting from the humeroulnar joint compressed the ulnar nerve, and Congo red staining revealed that the mass contained amyloid deposition. Synovial proliferation resulting from amyloid arthropathy of the elbow joint appears to be the primary cause of this disease.

Arthroscopic findings of Kienbock's disease

PurposeKienböck’s disease affects the lunate bone, and osteoarthritic changes progress as the disease advances; however, relatively few studies have reported the arthroscopic findings of Kienböck’s disease, and these reports have been in small populations. The purpose of this study was to review arthroscopic findings in a larger population than studied in previous reports.MethodsWe retrospectively reviewed 57 patients who underwent radial osteotomy for Kienböck’s disease after arthroscopy of both the radiocarpal and midcarpal joints. All arthroscopic findings were classified as follows in terms of the location of osteoarthritic changes: lunate fossa of the radius, proximal/distal surface of the lunate bone, and capitate head. Radiological stages were classified according to the modified Lichtman’s classification system.ResultsAll but two patients had cartilage lesions in the proximal lunate cartilage. Older patients had significantly more cartilage lesions, but radiological stage showed no correlation with the number of cartilage lesions.ConclusionsThis study demonstrated that the proximal lunate bone was affected in most cases of Kienböck’s disease and that older patients had more cartilage lesions.

Arthroscopic lunate morphology and wrist disorders

PurposeThe lunate is classified into two types, one with a single distal facet and the other with two distal facets. The effect of lunate type on the incidence of wrist disease and trauma remains unclear. The purpose of this study is to evaluate a potential association between lunate morphology and wrist disorders.MethodsWe retrospectively reviewed the cases of 637 patients who had undergone wrist arthroscopy for wrist disorders. Patient charts and arthroscopic video images were reviewed retrospectively. We defined lunate type based on the Viegas classifications, according to its distal facet from a midcarpal arthroscopic image. Patient wrist disorders were divided into four groups: fractures and dislocations, Kienböck’s disease, ulnar wrist pain, and degenerative disease.ResultsA Viegas type 1 lunate was observed in 349 wrists and a type 2 lunate in 288 wrists. Incidence of the type 2 lunate was different between the groups and was significantly lower for the Kienböck’s disease and ulnar wrist pain groups than for the trauma and degenerative groups.ConclusionsThe present study revealed a variable incidence of lunate type in wrist disorders. The proportion of type 2 lunates was lower in Kienböck’s disease and ulnar wrist pain.

Transplantation of embryonic motor neurons into peripheral nerve combined with functional electrical stimulation restores functional muscle activity in the rat sciatic nerve transection model

Reinnervation of denervated muscle by motor neurons transplanted into the peripheral nerve may provide the potential to excite muscles artificially with functional electrical stimulation (FES). Here we investigated whether transplantation of embryonic motor neurons into peripheral nerve combined with FES restored functional muscle activity in adult Fischer 344 rats after transection of the sciatic nerve. One week after sciatic nerve transection, cell culture medium containing (cell transplantation group, n = 6) or lacking (surgical control group, n = 6) dissociated embryonic spinal neurons was injected into the distal stump of the tibial and peroneal nerves. Electrophysiological and tissue analyses were performed in the cell transplantation and surgical control groups 12 weeks after transplantation, as well as a in naïve control group (n = 6) that received no surgery. In the cell transplantation group, ankle angle was measured during gait, with and without FES of the peroneal nerve. Ankle angle at mid‐swing was more flexed during gait with FES (26.6 ± 8.7°) than gait without FES (51.4 ± 12.8°, p = 0.011), indicating that transplantated motor neurons in conjunction with FES restored ankle flexion in gait, even though no neural connection between central nervous system and muscle was present. These results indicate that transplantation of embryonic motor neurons into peripheral nerve combined with FES can provide a novel treatment strategy for paralysed muscles. Copyright

Interindividual anatomical variations affect the plate-to-bone fit during osteosynthesis of distal radius fractures.

We hypothesized that interindividual variations in the teardrop, which represents the volar projection of the lunate facet of the distal radius, cause unsatisfactory fitting of the volar locking plate to the bone. This can cause flexor tendon ruptures. Herein, we conducted a cross‐sectional study and measured the ratio of teardrop height and the teardrop inclination angle as parameters of teardrop configuration for 200 standardized lateral radiographs (average age of the patients, 51 years). We also quantified the influence of the teardrop morphology by analyzing the fit of three locking plates to three radii with differing teardrop inclination angles using a three‐dimensional computer‐aided design system. The average ratios of the teardrop height and teardrop inclination angle were 0.42° (0.30–0.56°) and 28.8° (9.9–44.9°), respectively. The teardrop inclination angle was moderately correlated with age in men but not in women. In the plate‐to‐bone fit analyses, the fit of all the plates was significantly different between bones, with the configuration of the radius with the lowest teardrop inclination angle being the closest approximation to that of each plate. We demonstrated the interindividual variation in the shape of the teardrop and its influence on the fit of the volar plate, highlighting the importance of careful plate selection for achieving osteosynthesis of bones with a high teardrop inclination angle.

Anterior interosseous nerve and posterior interosseous nerve involvement in neuralgic amyotrophy

OBJECTIVES The aim of this study was to gain a better understanding of anterior interosseous nerve and posterior interosseous nerve involvement in neuralgic amyotrophy. METHODS In a retrospective chart review, 51 cases (49 patients) with anterior and posterior interosseous nerve syndrome were investigated in terms of their symptoms, course of disease, and prognosis. RESULTS Patients first presented with pain in 52.9% of cases. The location of the pain was distal to the shoulder in most cases (85.1%). Sensory involvement was found in 27.5% of patients, and patients with pain before paresis had fewer sensory symptoms (p=0.006). Neurolysis significantly improved Hand20 scores, but conservative treatment did not (p=0.020 vs. 0.204). CONCLUSIONS Patients with anterior interosseous nerve and posterior interosseous nerve affection in neuralgic amyotrophy had less pain. Neurolysis can be superior to conservative treatment in the patients with focal constrictions and no spontaneous recovery.

Feasibility of four-dimensional preoperative simulation for elbow debridement arthroplasty

BackgroundRecent advances in imaging modalities have enabled three-dimensional preoperative simulation. A four-dimensional preoperative simulation system would be useful for debridement arthroplasty of primary degenerative elbow osteoarthritis because it would be able to detect the impingement lesions.MethodsWe developed a four-dimensional simulation system by adding the anatomical axis to the three-dimensional computed tomography scan data of the affected arm in one position. Eleven patients with primary degenerative elbow osteoarthritis were included. A “two rings” method was used to calculate the flexion-extension axis of the elbow by converting the surface of the trochlea and capitellum into two rings. A four-dimensional simulation movie was created and showed the optimal range of motion and the impingement area requiring excision. To evaluate the reliability of the flexion-extension axis, interobserver and intraobserver reliabilities regarding the assessment of bony overlap volumes were calculated twice for each patient by two authors. Patients were treated by open or arthroscopic debridement arthroplasties. Pre- and postoperative examinations included elbow range of motion measurement, and completion of the patient-rated questionnaire Hand20, Japanese Orthopaedic Association-Japan Elbow Society Elbow Function Score, and the Mayo Elbow Performance Score.ResultsMeasurement of the bony overlap volume showed an intraobserver intraclass correlation coefficient of 0.93 and 0.90, and an interobserver intraclass correlation coefficient of 0.94. The mean elbow flexion-extension arc significantly improved from 101° to 125°. The mean Hand20 score significantly improved from 52 to 22. The mean Japanese Orthopaedic Association-Japan Elbow Society Elbow Function Score significantly improved from 67 to 88. The mean Mayo Elbow Performance Score significantly improved from 71 to 91 at the final follow-up evaluation.ConclusionWe showed that four-dimensional, preoperative simulation can be generated by adding the rotation axis to the one-position, three-dimensional computed tomography image of the affected arm. This method is feasible for elbow debridement arthroplasty.