Takuya Mishiro

Fractures of the distal end of radius in elderly patients: a comparative study of anatomical and functional results.

The functional and anatomical results of distal end of radius fractures with severe displacement in 22 elderly patients are reviewed in this retrospective study. The mean age of the patients was 69.4 years (range, 60–88 years) and the mean follow-up period was 24 months (range, 12–53 months). According to the sum of demerit points (Saito, 1983), the latest follow-up functional end results were ‘excellent’ in 64% of fractures and ‘good’ in 36%. As for the anatomical results at follow-up, the average radial tilt was 20.7°, ulnar variance was 4.0 mm, and palmar tilt was −2.7° respectively. Though most of the patients had satisfactory outcome and the functional results did not correlate with the radiographic evidence of minor deformities, the functional results of the patients with radial shortening of 6 mm or over were poor. Furthermore, the grip power was the most significant factor related to subjective evaluation and did not improve significantly in patients with the nondominant hand injured.

Long adult spinal deformity fusion to the sacrum using rhBMP-2 versus autogenous iliac crest bone graft.

Study Design. Comparative study. Objective. To compare the radiographic outcome of patients undergoing long spinal deformity surgery to the sacrum/ilium, using either rhBMP-2 without iliac crest bone graft (ICBG) or ICBG without rhBMP-2. Summary of Background Data. rhBMP-2 has been shown to be more effective in promoting successful bone union in patients undergoing single level lumbar spinal fusion than ICBG. However, to the best of our knowledge, there are no studies that compare the efficacy of rhBMP-2 versus ICBG in long spinal deformity surgery. Methods. To obtain uniform background, we selected patients with adult spinal deformity who underwent primary spinal fusion from the thoracic spine to the sacrum/ilium and had a minimum 2-year follow-up. Fifty-five consecutive patients, consisting of 32 patients who underwent a fusion using ICBG without rhBMP-2 (ICBG group) and 23 patients who underwent a fusion using rhBMP-2 without ICBG (BMP group) were analyzed. Results. The 2 groups were similar with respect to age, gender, smoking history, comorbidity, and body mass index. The average number of vertebrae fused (11.3 in both groups) and the degree of preoperative deformity (major Cobb angle 58.3° in ICBG group vs. 54.2° in BMP group) were also similar in both groups. All but 2 patients had both anterior and posterior surgery. Both groups were similar in terms of final deformity correction. The average total amount of rhBMP-2 used in the BMP group was 119.2 mg (anterior 11.6 mg/level; posterior 10.0 mg/level). Of the 32 patients in the ICBG group, 9 patients (28.1%) developed a pseudarthrosis, while only 1 of 23 patients (4.3%) in the BMP group developed a pseudarthrosis with the caveat that the follow-up period wasshorter in the BMP group (average follow-up of 4.9 vs. 2.7 years). Conclusion. The pseudarthrosis rate in the BMP group compares favorably to pseudarthrosis rate in ICBG group, suggesting that the use of rhBMP-2 without iliac harvesting leads to a competitive fusion rate in long adult spinal deformity surgery, while avoiding ICBG harvest site morbidity.

Etiology and revision surgical strategies in failed lumbosacral fixation of adult spinal deformity constructs.

Study Design. Retrospective case analysis. Objective. The purpose of this study was to evaluate the etiology and salvage strategies of failed lumbosacral fixation in adult spinal deformity patients. Summary of Background Data. When extending a long spinal deformity fusion to the sacrum, the lumbosacral junction is a common site for implant problems and pseudarthrosis. Methods. Clinical and radiographic results of 33 patients (26 women/seven men; average age, 53.5 years; range, 21–73) diagnosed and treated for lumbosacral fixation failure between 1995 and 2007 were reviewed. Twenty-one of the 33 patients underwent revision surgery at one institution for these failures and were followed postoperatively for more than 2 years (average, 50.7 months). Results. Twenty-nine of these 33 patients had two sacral screws, two patients one sacral screw, and two patients none. Bicortical sacral screws were placed in 18 patients, only 12 had distal fixation to the sacral screws (bilateral iliac screws, n = 9; others, n = 3). Seventeen of 19 patients without distal fixation to the sacral screws had screw loosening/pullout at L5 or S1. Anteriorly at L5–S1: 4/6 bone grafts collapsed, 5 of 15 intervertebral discs without anterior column support collapsed, and two of 12 titanium cages subsided into the endplates. Rod breakage between L5 and S1 (n = 9) was seen only in patients with distal fixation to the sacral screws. Nineteen of 21 revision patients received two bicortical sacral screws, whereas 20 received distal fixation to the sacral screws consisting of bilateral iliac screws in 16. Nineteen patients received anterior column support at L5–S1. Fifteen of 21 revision patients achieved solid fusion at ultimate follow-up; however, six had additional rod breakage or dislodgement at the lumbosacral junction. Conclusion. With long fusions to the sacrum in the treatment of spinal deformity, the use of bilateral S1 screws alone may allow for screw loosening/pullout and/or L5–S1 cage/graft collapse/subsidence. Adding bilateral iliac screws and an anterior structural cage/graft at L5–S1 will protect the S1 screws, but may still allow L5–S1 rod breakage/dislodgement because of lumbosacral pseudarthrosis. Revision surgery in these patients remains a challenge.

Surgical treatment of lumbar disc herniation in elderly patients

Between 1995 and 1999, 12 patients aged 65 years or more (mean 70.2) with lumbar disc herniation, underwent partial laminectomy and nucleotomy. The results were compared with those of 25 younger patients aged between 20 and 40 years (mean 30.1), who underwent the same surgical procedure. The Japanese Orthopedic Association (JOA) score was used to assess the clinical outcome. The minimum follow-up was 12 months. The pre- and post-operative total JOA scores and the rate of improvement of the JOA score were not significantly different between the elderly (11.1, 24.3 points, and 74.1%), and the younger group (11.6, 26.4 points and 84.5%). The results of this study indicate that the outcome of lumbar discectomy in elderly patients is as good as in younger patients.

Increasing lumbar lordosis of adult spinal deformity patients via intraoperative prone positioning.

Study Design. A retrospective evaluation. Objective. To evaluate the change in lumbar lordosis in spinal deformity patients who underwent an instrumented posterior spinal fusion on the Orthopedic Systems Inc. (OSI) “Jackson” frame. Summary of Background Data. Intraoperative prone positioning with hip extension may posturally increase lumbar lordosis during adult spinal deformity reconstructive surgery, as has been shown in adult lumbar degenerative surgery. Methods. Radiographs of 44 operative spinal deformity patients (43 females/1 male; mean age, 57.4 years) were analyzed. Diagnoses included idiopathic scoliosis (29), degenerative lumbar scoliosis (9), and other (6). Total lumbar lordosis (T12–S1), segmental disc angles, and C7 plumbline were measured on preoperative upright and supine, intraoperative prone, and postoperative upright lateral radiographs. All patients were positioned intraoperatively with hip extension on the OSI frame. Results. Average preoperative upright and supine, intraoperative prone, and postoperative upright lumbar lordosis (T12–SAC) measurements were −38.1°, −46.0°, −46.2°, and −51.8°, respectively (P < 0.05 for preoperative upright to all other comparisons). Two groups were noted: those with increased lumbar lordosis (>5°) during intraoperative prone positioning (n = 25, increased lordosis group) as compared to the preoperative measurement versus those with minimal to no change in lordosis (≤5°) during intraoperative prone positioning (n = 19, unchanged lordosis group). The corresponding lumbar lordosis measurements for the increased lordosis group were −25.9°, −40.0°, −43.1°, and −48.9° (P < 0.05 for preoperative upright to all other comparisons). The corresponding lumbar lordosis measurements for the unchanged lordosis group were −54.2°, −53.8°, −50.3°, and −55.7° (no significant differences). Preoperative upright lumbar lordosis in the unchanged lordosis group was substantially higher than increased lumbar lordosis group (P < 0.05). Conclusion. Adult spinal deformity patients with preoperative hypolordosis who were positioned prone during reconstructive surgery had an enhanced lumbar lordosis via positioning alone compared with theirpreoperative upright radiographs. Conversely, those with substantial preoperative lordosis remained unchanged with intraoperative prone positioning. This knowledge will help in the surgical planning of adult spinal deformity reconstructive surgery to optimize sagittal alignment and balance.

Adult onset tethered cord syndrome associated with intradural dermoid cyst. A case report.

Study design:A case report and a review of literature.Objectives:To describe a rare case of adult onset tethered cord syndrome associated with intradural dermoid cyst.Setting:General Orthopedics, Japan.Methods:A 50-year-old woman was referred to us because of right leg pain and pollakiuria. Neurological examinations and radiological assessments including myelography, computerized tomography scan and Magnetic resonance image were carried out. We diagnosed it as the adult onset tethered cord syndrome associated with an intradural cystic lesion.Results:The cystic lesion was totally removed following laminectomy from L5 through S4. Histologically, the tumor was diagnosed as a dermoid cyst.Conclusions:Intradural dermoid could produce adult onset tethered cord syndrome, but it was not reported in the English literatures to our knowledge.

Characteristics of velocity-controlled knee movement in patients with cervical compression myelopathy: what is the optimal rehabilitation exercise for spastic gait?

Study Design. The isokinetic strength of knee extensors and flexors was measured at various controlled velocities in patients with spastic paraparesis caused by cervical compression myelopathy. Objective. To evaluate leg function objectively in patients with myelopathy. Summary of Background Data. Cervical compression myelopathy causes varying degrees of spastic paresis in the legs and affects the activities of patients. However, the leg function characteristics of the patients have not been fully elucidated. Methods. Velocity-controlled voluntary knee movements were studied in 39 patients (25 men and 14 women) with compression myelopathy. Their mean age was 60.2 years (range, 44–77 years). The patients were divided into Group A (ambulation without aid, n = 22) and Group AA (ambulation with aid, n = 17). Isometric peak torque values were measured in knee flexor and extensor muscles at 60° of knee flexion, and isokinetic peak torque values were determined in maximal voluntary concentric movements of these muscles at constant angle velocities of 40°, 80°, 120°, 160°, and 180° per second. The relative strength (percentage of isometric peak torque value) of the isokinetic motion was calculated at each velocity. Results. In both groups, the relative strength decreased as the velocity increased, and the degree of reduced strength in the flexors at the high velocities of 160° and 180° per second was significantly greater in Group AA than in Group A (P < 0.05), whereas no significant difference was found in the extensors between the groups. Conclusions. The results indicate that isokinetic strength at a high velocity may reflect the severity of spastic paresis in the legs resulting from compression myelopathy.

Clinical evaluation of aged patients who underwent surgery for femoral neck fractures — Comparative study of clinical results according to age

The objective was to assess mortality and ambulatory ability for elderly patients over 90 years of age with femoral neck fractures treated surgically. From January 1998 to March 1999, 60 patients aged over 80 years were chosen for the study. The patients had a mean age of 87.1 years. The mean follow-up period was 12.9 months. The patients were classified into three groups according to age: group A (80–84 years old), group B (85–89 years old) and group C (over 90 years old). The rates of recovered postoperative walking ability were 72.2% (13/18) of group A, 65.2% (15/23) of group B and 84.2% (16/19) of group C. These patients were followed up until death or for at least one year. The overall mortality rates were 11.1% (2/18) of group A, 17.4% (4/23) of group B and 10.5% (2/19) of group C.

Insertional Torque in Cervical Vertebrae Lateral Mass Screw Fixation: Magerl Technique Versus Roy-Camille Technique.

Study Design: This is a prospective multicenter comparison study. Objective: To measure the insertional torque (IT) for cervical vertebra lateral mass screw (LMS) fixation using the Magerl and Roy-Camille methods, at the discretion of the surgeon. Summary of Background Data: Current fixation methods for patients with preoperative cervical spine instability use LMSs; however, few studies have closely examined intraoperative IT. Patients’ bone quality was not measured. Methods: A total of 637 posterior cervical multiaxial screws were inserted for LMS (C3–C6) (Magerl technique, 423; Roy-Camille technique, 214) in 107 cases. Patients’ mean age was 66 years. Patients treated with the Magerl method were divided into 2 groups, with the men in the MM group and the women in the MF group. Similarly, patients treated with the Roy-Camille method were divided into 2 groups, with the men in the RM group and the women in the RF group. The contralateral cortex was penetrated, and the IT at cerclage was measured at the last time. Results: IT of the lateral mass screw was 53.8±22.4, 45.4±21, 45.5±16.9, and 34±16.4 cN.m in the MM group (258), MF group (165), RM group (163), and RF group (51), respectively. The MM group had a significantly higher IT than the other 3 groups, and the RM group had a significantly higher IT than the RF group. When the correlation between screw length and IT was evaluated, IT was significantly (P<0.05) higher with a longer screw by the Magerl method. Conclusions: The IT was higher with the Magerl method with a longer screw. Screw length and IT were not correlated with the Roy-Camille method; furthermore, the Roy-Camille method went through bilateral cortical bone perpendicularly, so that IT was determined by the fixation power in the cortical part of the bone, which was not thought to be affected by screw length. Level of Evidence: Level III.