The Effect of Static Stretching Duration on Muscle Blood Volume and Oxygenation.

ABSTRACT: Matsuo, H, Kubota, M, Shimada, S, Kitade, I, Matsumura, M, Nonoyama, T, Koie, Y, Naruse, H, Takahashi, A, Oki, H, Kokubo, Y, and Matsumine, A. The effect of static stretching duration on muscle blood volume and oxygenation. J Strength Cond Res 36(2): 379-385, 2022-Muscle blood volume increases due to stretching; however, the minimum duration of stretching to sustainably increase the muscle blood volume after stretching has not yet been elucidated. This study examined whether the duration of static stretching influenced the muscle blood volume and oxygenation. Ten healthy male subjects participated in this controlled laboratory study. Static stretching of the gastrocnemius muscle was performed for 5 durations (20 seconds, and 1, 2, 5, and 10 minutes). Changes in both the total-Hb (ΔtHb), as an index of blood volume, and tissue oxygenation index (ΔTOI) from baseline were determined using near-infrared spectroscopy. Both the ΔtHb and ΔTOI decreased during stretching and increased after stretching. The minimum value of ΔtHb during stretching did not differ in each of the 5 durations, but minimum ΔTOI progressively decreased with longer durations of stretching. The peak value of ΔtHb after stretching increased with longer durations of stretching. The value of ΔtHb at 5 minutes after the end of stretching increased with more than 2 minutes of stretching compared with 20 seconds of stretching, although the value of ΔtHb did not significantly differ between the 2, 5, and 10 minutes' durations. These findings suggest that a longer duration of stretching elicits a decrease in muscle oxygenation during stretching, and an increase in both the muscle blood volume and oxygenation after stretching. The results indicated that the minimum duration of stretching to sustain an increase in the muscle blood volume after stretching is 2 minutes.

Effects of knee extension exercise starting within 4 h after total knee arthroplasty.

PURPOSE: To determine the beneficial effects of knee extension exercise applied from 4 h after TKA. METHODS: Patients undergoing TKA for osteoarthritis were assigned to early rehabilitation (n = 41) and control rehabilitation (n = 39) groups. Rehabilitation of knee extension exercise was started within 4 h postoperative in the early group and 2 days after surgery in the control group. Joint range of motion and pain were assessed before surgery and at 3 days to 12 months after surgery. Muscle strength and gait parameters were assessed before and 3 weeks after surgery. RESULTS: Extension range of motion was significantly increased in the early group than the control at 3 days, 3 weeks and 6 months after surgery. In gait parameters, peak knee flexion and extension angles during stance phase were significantly improved in the early group than the control group at 3 weeks after surgery. Flexion range of motion was increased in the early group than the control at 12 months after surgery. CONCLUSION: Starting knee extension exercise within 4 h after TKA reduced the early loss of extension range of motion and improved gait pattern and seemed to contribute to be better functional outcome one year after surgery.

Intraarticular injection of processed lipoaspirate cells has anti-inflammatory and analgesic effects but does not improve degenerative changes in murine monoiodoacetate-induced osteoarthritis.

BACKGROUND: Previous basic research and clinical studies examined the effects of mesenchymal stem cells (MSCs) on regeneration and maintenance of articular cartilage. However, our pilot study suggested that MSCs are more effective at suppressing inflammation and pain rather than promoting cartilage regeneration in osteoarthritis. Adipose tissue is considered a useful source of MSCs; it can be harvested easily in larger quantities compared with the bone marrow. The present study was designed to evaluate the anti-inflammatory, analgesic, and regenerative effects of intra-articularly injected processed lipoaspirate (PLA) cells (containing adipose-derived MSCs) on degenerative cartilage in a rat osteoarthritis model. METHODS: PLA cells were isolated from subcutaneous adipose tissue of 12-week-old female Sprague-Dawley rats. Osteoarthritis was induced by injection of monoiodoacetate (MIA). Each rat received 1 × 106 MSCs into the joint at day 7 (early injection group) and day 14 (late injection group) post-MIA injection. At 7, 14, 21 days after MIA administration, pain was assessed by immunostaining and western blotting of dorsal root ganglion (DRG). Cartilage quality was assessed macroscopically and by safranin-O and H&E staining, and joint inflammation was assessed by western blotting of the synovium. RESULTS: The early injection group showed less cartilage degradation, whereas the late injection group showed cartilage damage similar to untreated OA group. The relative expression level of CGRP protein in DRG neurons was significantly lower in the two treatment groups, compared with the untreated group. CONCLUSIONS: Intra-articular injection of PLA cells prevented degenerative changes in the early injection group, but had little effect in promoting cartilage repair in the late injection group. Interestingly, intra-articular injection of PLA cells resulted in suppression of inflammation and pain in both OA groups. Further studies are needed to determine the long-term effects of intra-articular injection of PLA cells in osteoarthritis.

Extensive Loss of Tibialis Anterior Tendon: Surgical Repair With Split Tendon Transfer of Tibialis Posterior Tendon: A Case Report.

Extensive damage of the tibialis anterior tendon is rare and mainly caused by trauma. Surgical treatment of these injuries can become challenging owing to the limited availability of autogenous graft resources for reconstruction of the defect. In the present case report, we describe a large defect in the midfoot soft tissue after a traffic injury, which included complete loss of the tibialis anterior tendon. The tendon was reconstructed by split tendon transfer of the tibialis posterior tendon without sacrificing function, which was confirmed by the follow-up examination at 6 years after injury. We believe split tendon transfer of the tibialis posterior tendon can be one of the treatment options for patients with extensive disruption of the tibialis anterior tendon.

Long-term clinical outcome of acetabular cup revision surgery: comparison of cemented cups, cementless cups, and cemented cups with reinforcement devices.

The aim of the present study was to analyze the clinical and radiographic outcomes and Kaplan-Meier survivorship of patients who underwent revision surgeries of the acetabular cup that had sustained aseptic loosening. We reviewed 101 consecutive patients (120 hips; 10 men 11 hips; 91 women 109 hips; age at surgery 66 years; range 45-85) who underwent acetabular component revision surgery, at a follow-up period of 15.6 years (range 10-32). To evaluate the state of the acetabulum, acetabular bony defects were classified according to the AAOS classification based on intraoperative findings: type I (segmental deficiencies n = 24 hips), type II (cavity deficiency n = 48), type III (combined deficiency n = 46), and type IV (pelvic discontinuity n = 2). The Harris hip score improved from 42.5 ± 10.8 (mean ± SD) before surgery to 74.9 ± 14.6 points at follow-up. The survival rates of the acetabular revision surgery with cemented, cementless, and cemented cups plus reinforcement devices were 74, 66, and 82 %, respectively. The difference in the survival rate between the cemented and cementless group was marginal (p = 0.048 Gehan-Breslow-Wilcoxon, p = 0.061 log-rank), probably due to the early-stage failure cases in the cementless group. The cementless and reinforcement groups included nine early-stage failure cases. To prevent early-stage failure, we recommend the cementless cups for types I and II acetabular bone defects with adequate contact between host bone and acetabular component, and the cemented cup with or without reinforcement devices, together with restoration of bone stock by impaction or structured bone grafting, for cases lacking such contact.

Modified metaphyseal-loading anterolaterally flared anatomic femoral stem: five- to nine-year prospective follow-up evaluation and results of three-dimensional finite element analysis.

We have designed a proximal-fitting, anterolaterally flared, arc-deposit hydroxyapatite-coated anatomical femoral stem (FMS-anatomic stem; KYOCERA Medical, Osaka, Japan) for cementless total hip arthroplasty (THA) for Japanese patients with dysplastic hip osteoarthritis, using a nonlinear three-dimensional finite element analysis simulating loading conditions. The Anatomic Fit stem was modified in the region of the arc-sprayed surface, to allow more proximal appearance of spot welds. The aim of the present study was to analyze the clinical and radiographic outcomes of patients who underwent THA using this stem. We reviewed 73 consecutive patients (79 hips; 13 men 16 hips; 60 women 63 hips; age at surgery, 57.6 years, range, 35-78) who underwent cementless THA using the Anatomic Fit stem, at a follow-up period of 7.1 years (range, 5.1-9.4). Harris Hip score improved from 40.7 ± 17.1 before surgery to 91.0 ± 5.2 points at follow-up. The 7.1-year stem survival rate was 100%. Radiographs at follow-up confirmed the stability of the femoral stems within the femoral canal in all cases, with sufficient bone ingrowth. None of the patients had subsidence of the stem exceeding 2.0 mm within the femoral canal or changes in varus or valgus position of more than 2.0°. The Anatomic Fit stem provided excellent results. The nonlinear three-dimensional finite element analysis demonstrated that the stem-bone relative motion was 10 µm at the proximal end of the stem and proximal load transfer. Our analysis confirmed reduced radiolucency around the stem, minimal subsidence, appropriate stress shielding, and promising medium-term stability within the femoral canal.

Dislocated intra-articular femoral head fracture associated with fracture-dislocation of the hip and acetabulum: report of 12 cases and technical notes on surgical intervention.

This report describes case series of the femoral head fractures associated with fracture-dislocation of the hip joint to evaluate the mid- and long-term outcomes and to highlight the surgical technique of fixation of the femoral head from the posterior trochanteric flip osteotomy approach. Twelve patients (6 men and 6 women) with dislocated femoral head fractures (mean age at the time of injury, 56 years; range, 23-80) were followed up for mean period of 9.7 years (range, 5-20). All dislocations were reduced within less than 6 h after the injury. The type of femoral head fracture was classified according to the Pipkin classification on radiographs and CT. Five patients were classified as type I, 2 as type II, 2 as type III, and 3 as type IV. The clinical and radiological outcomes were assessed by Thompson and Epstein's regimen. Excluding 2 patients with Pipkin type III, the outcome of 9 patients was excellent/good, and poor in 1. The latter patient sustained Pipkin type IV and developed osteoarthritis 1 year after surgery and consequently required total hip arthroplasty. We conclude that small fragment of the femoral head less than 1 cm can be removed, while larger fragments should be fixed by bioabsorbable screws or pins in all types of femoral head fractures. In Pipkin type IV fractures, surgeons should always take anatomical reduction in the acetabulum into consideration during surgery.

Fracture of the acetabulum: a retrospective review of ninety-one patients treated at a single institution.

Acetabular fracture result in fairly good outcome after the anatomic reduction in the displaced fracture fragments and damaged joint structure, but some patients will inevitably suffer from hip joint problems during their courses after the insult. We retrospectively reviewed 91 patients with acetabular fractures to investigate the causes of clinical failure and relationship among the fracture types, selected treatment options and their courses. Ninety-one patients (73 men and 18 women) with an average age of 49 years (range 18-80) at the time of injury were followed up for an average of 8.6 years (range 2-18). Judet-Letournel classification of fracture type and Matta's rating regimen of functional and radiographic patient' assessment were conducted. Conservative treatment was provided in 20 patients, in which 19 attained excellent/good, and one fair clinical results. All achieved excellent/good radiographic outcome. Surgically treated patients (n = 71) with critical dislodgement of the fracture fragment showed that 64 (90%) attained excellent/good and 7 (10%) fair/poor clinical outcomes. Sixty-three (89%) attained excellent/good and 8 (11%) fair/poor postoperative radiographic outcome. Five patients with poor radiographic outcome after surgery subsequently required total hip arthroplasty, due to the development of hip joint osteoarthritis in 3 and femoral head avascular necrosis in 2. We conclude that displacement of the joint surface should be reduced to less than 3 mm in accordance with the selection of the most appropriate surgical approach for open reduction/fixation in each fracture type; however, comminuted fracture and avascular necrosis of the femoral head may be the cause of poor clinical results.

Changes in gait pattern and hip muscle strength after open reduction and internal fixation of acetabular fracture.

OBJECTIVES: To characterize changes in the gait pattern at 3 and 12 months after surgery for acetabular fracture, to assess the relationship between various gait parameters and hip muscle strength, and to determine the factors associated with gait disorders that correlate with gait parameters measured at 12 months after surgery. DESIGN: Prospective cohort study. SETTING: University hospital. PARTICIPANTS: Patients (N=19) with acetabular fractures were treated by open reduction and internal fixation (ORIF) and examined at 3 and 12 months postoperatively. The study also included a similar number of sex- and age-matched control subjects. INTERVENTIONS: Postoperative rehabilitation program. MAIN OUTCOME MEASURES: Spatiotemporal, kinematic, and kinetic variables of gait and strength of hip flexor, adductor, and abductor muscles at 3 and 12 months after ORIF. RESULTS: Walking velocity at 3 months after ORIF was slower in the patients than in the control subjects; however, walking velocity at 12 months was similar in the 2 groups. Although most of the kinematic and kinetic variables showed recovery to control levels at 3 and 12 months after ORIF, recovery was incomplete for pelvic forward tilt and hip abduction moment even at 12 months after ORIF. The greatest loss of muscle strength was noted in the hip abductors, where the average deficit was 35.4% at 3 months and 24.6% at 12 months. There was a significant relationship between hip abductor muscle strength and hip abduction moment at 3 months (R(2)=.63); however, this relationship diminished at 12 months (R(2)=.14). The presence of associated injuries correlated with lack of recovery of the peak hip abduction moment. CONCLUSIONS: Pelvic forward tilt and peak hip abduction moment showed incomplete recovery at 12 months after ORIF with subsequent conventional and home exercise rehabilitation programs. Our results suggest that improvement of hip abductor muscle strength in the early postoperative period could improve the peak hip abduction moment.

Polarization of infiltrating macrophages in the outer annulus fibrosus layer associated with the process of intervertebral disc degeneration and neural ingrowth in the human cervical spine.

BACKGROUND CONTEXT: As no infiltrating macrophages exist in healthy discs, understanding the role of infiltrating macrophages including their polarity (M1 and M2 phenotypes) in intervertebral discs (IVDs) is important in the assessment of the pathomechanisms of disc degeneration. PURPOSE: To determine the relationship between infiltrating macrophage polarization and the progression of human cervical IVD degeneration. STUDY DESIGN: Histopathological study using harvested human cervical IVDs. METHODS: IVDs collected during anterior cervical decompression from 60 patients were subjected to immunostaining and immunoblotting. The samples were classified as type 0-3 according to the percentage of CD16- and CD206-positive cells to CD68-positive cells in the outer annulus fibrosus layer. The number of vessels and nerve fibers and the severity of chronic inflammation with a focus on inflammatory cell infiltration, fibrosis, and capillary proliferation were also assessed. RESULTS: The number of CD16-positive cells was the highest in type 2 IVDs, and was suppressed following the infiltration of CD206-positive cells. The degree of chronic inflammation was significantly higher in type 2 and type 3 IVDs, and the number of nerve fibers was significantly higher in type 3 IVDs. The endothelial cells of small vessels were positive for nerve growth factor, brain-derived neurotrophic factor, and neurotrophin-3 expression. Staining for tropomyosin receptor kinase (Trk)-A, Trk-B, and Trk-C was positive in aberrant fibers. In immunoblot analysis, the expression levels of these neurotrophic factors and receptors were significantly higher in type 2 and 3 IVDs. CONCLUSIONS: The polarity of macrophages around newly developed microvasculature might be altered with cervical IVD degeneration. A higher number of infiltrating M1 macrophages around the vessels was associated with chronic inflammation; however, their number got suppressed following the infiltration of M2 macrophages. The expression of neurotrophins in the capillaries of small vessels might contribute to neural ingrowth into degenerated IVDs. CLINICAL SIGNIFICANCE: Clarifying macrophages polarity change around new microvasculature associated with progression of IVD degeneration could enhance our understanding of the underlying mechanisms of neural ingrowth into degenerated IVDs and lead to development of a novel therapeutic target for prevention of IVD.

Effect of the COVID-19 pandemic on the oral health and nutritional status of Japanese older adults who underwent total hip or knee arthroplasty: A 3-year single-institution retrospective cohort study.

The coronavirus disease 2019 (COVID-19) pandemic affected the physical and mental health, socioeconomic status, and community behavior of people worldwide. The aim of this retrospective cohort study was to analyze the impact of the COVID-19 pandemic on the oral health and nutritional status of Japanese older adults based on the results of preoperative assessment in patients who underwent total hip or knee arthroplasty under general anesthesia. This study included older adults (≧65 years) who underwent total hip or knee arthroplasty in whom orthopantomography was performed for preoperative oral health assessment, during January 2019 to December 2021. Gender, age, number of family members living together, number of teeth, body mass index, and serum total protein and serum albumin levels were collected for analysis of this study. A total of 201 patients aged 65 to 89 years participated in the study. While the COVID-19 pandemic has had no impact on the oral health status, there has been a drop in serum albumin level from the results of multivariable-adjusted regression analysis considering age, gender, number of family members, and time. The COVID-19 pandemic has affected the serum albumin level of Japanese orthopedic patients aged 65 years or older.

Distribution and Polarization of Hematogenous Macrophages Associated with the Progression of Intervertebral Disc Degeneration.

STUDY DESIGN: In vivo study using immunostaining and immunoblot analysis. OBJECTIVE: To determine the distribution of bone marrow-derived macrophages (BMDMs), macrophage polarization and cytokine expression in the process of intervertebral disc (IVD) degeneration. SUMMARY OF BACKGROUND DATA: Knowledge of the detailed distribution of exogeneous macrophages in the disc degeneration process is important for understanding the pathomechanisms and establishing novel therapeutic targets. METHODS: To distinguish BMDMs, GFP-labeled bone marrow chimeric rats (n = 12) were generated. The degenerative process of the intervertebral disc was reproduced in a rat caudal disc puncture model (n = 49). Immunofluorescence staining was performed to observe the distribution of BMDMs, Iba-1 and GFP double-positive cells, and Iba-1 and iNOS (M1 macrophage) or arginase-1 (M2 macrophage) double-positive cells. Immunoblot analysis was used to evaluate differences in cytokines (TNF-α, IL-1ß, IL-6, TGF-ß, IL-4, and IL-10) depending on the distribution of BMDMs. RESULTS: BMDMs infiltrated into the outer annulus fibrosus and endplate, while increasing tissue-resident macrophage was observed inside the annulus fibrosus/nucleus pulposus. The ratio of BMDMs and the polarity change differed among the regions. Especially in the endplate, BMDMs increased gradually and the macrophage phenotype was M2 dominant. Expression of IL-1ß decreased gradually at endplate, and that of IL-4 increased early after disc puncture at inside of the annulus fibrosus. CONCLUSION: During the disc degeneration process, BMDMs were observed mainly around the endplate and outside area of the annulus fibrosus, with few in the inside area of annulus fibrosus and nucleus pulposus. Compared to other IVD area, macrophage polarity and cytokine expression is concomitantly M2-dominant in endplate. Increased hematogenous M2-phenotype macrophages in endplate with progression of IVD degeneration could enhance our understanding of the underlying mechanisms of disc degeneration.Level of Evidence: N/A.

Metaphyseal-loading anterolaterally-flared femoral stem in cementless total hip arthroplasty: five- to eleven-year follow-up evaluation.

Using a nonlinear three-dimensional finite element analysis simulating loading conditions, we designed a new type of proximal-fitting, anterolaterally-flared, arc-deposit hydroxyapatite-coated anatomical femoral stem (FMS-anatomic stem; Japan Medical Materials, Osaka, Japan) for cementless total hip arthroplasty (THA) for Japanese patients with dysplastic hip osteoarthritis. The aim of the present study was to analyze the clinical and radiographic outcomes of the new stem. We reviewed 143 consecutive patients (164 hips; 13 men, 14 hips; 130 women, 150 hips; age at surgery, 56.6 +/- 7.6 years, mean +/- SD, range, 30-74) who underwent cementless THA using the FMS-anatomic stem at a single institution, with a follow-up period of 7.6 +/- 1.6 years (range, 5.3-11.0). Harris Hip score improved from 46.1 +/- 12.6 before surgery to 90.0 +/- 8.9 points post-THA. The 7.6-year survival rate of the stem was 99.0% after revision for aseptic loosening. Radiographs at follow-up confirmed the stability of the femoral stems within the femoral canal in all cases, with sufficient bone ingrowth. None of the patients had subsidence of the stem exceeding 2.0 mm within the femoral canal or changes in varus or valgus position of more than 2.0 degrees . The FMS-anatomic stem provided excellent results in patients with dysplastic hip osteoarthritis. Our analysis confirmed reduced radiolucency around the stem in Gruen zones, minimal subsidence, appropriate stress shielding, and promising medium-term stability within the femoral canal in our patients.

Rapidly progressive neuropathic arthropathy of the knee in possible association with a huge extruded cervical intervertebral disc herniation.

A 58-year-old woman with an insignificant stage of diabetes mellitus presented with rapidly progressive osteoarthritis of her right knee exhibiting painless but significant antero-posterior and lateral instability. In association, she had a huge extruded left-sided cervical intervertebral disc at the C4-5 level. Neurological examination of the upper limbs was normal but, she had diminished pinprick sensation on the right leg. Radiographic findings were consistent with neuropathic arthropathy of the knee. Anterior decompression with fusion of C4-5 and total knee arthroplasty using a semi-constrained-type artificial implant were performed in one stage. The patient regained nearly normal living activity following surgical intervention. We stress the possibility of rapid progression of knee joint arthropathy, as neuropathic knee, even in a patient with less significant symptoms and signs of cervical myelopathy caused by a huge extruded intervertebral disc.

Cyclic tensile strain facilitates ossification of the cervical posterior longitudinal ligament via increased Indian hedgehog signaling.

The pathomechanisms of initiation and progression of ossification of the posterior longitudinal ligament (OPLL) are unclear. Indian hedgehog (Ihh) and related signaling molecules are key factors in normal enchondral ossification. The purpose of this study is to investigate the contribution of mechanical strain to OPLL and the relationship of Ihh with OPLL. Sections of the posterior longitudinal ligament (PLL) were obtained from 49 patients with OPLL and from 7 patients without OPLL. Cultured PLL cells were subjected to 24 hours of cyclic tensile strain. To identify differentially expressed genes associated with cyclic tensile strain, microarray analysis was performed. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis identified upregulation of various genes, particularly of the Hedgehog signaling pathway; Ihh and related genes had increased expression compared with controls after 24-hour cyclic tensile strain. In immunoblotting analysis, Ihh, Runx2, Sox9, Gli2, Gli3, and smoothened (SMO) had significantly increased expression after 6- or 12-hour cyclic tensile strain. OPLL samples were strongly immunopositive for Ihh, Sox9, Runx2, Gli2, Gli3, and SMO in the ossification front of OPLL. These results suggest that cyclic tensile strain induces abnormal activation of Ihh and related signaling molecules, and this might be important in the ossification process in OPLL.

Functional outcomes after the treatment of hip fracture.

Osteoporotic hip fracture is a major public health issue. Estimation of the outcome and maximization of functional recovery after fracture is very important in the treatment of older patients. The purposes of this study were to clarify the functional outcomes after the treatment of hip fracture and to identify the factors that influence functional recovery. In the present study, 228 patients admitted to an acute-care hospital from January 2016 to June 2018 were evaluated. The patients were categorized into a trochanteric fracture group (n = 128) and a neck fracture group (n = 100). We retrospectively reviewed their ambulation ability 6 months after fracture using the Functional Ambulation Category (FAC) score. The other survey items were the presurgical duration, length of hospital stay, time until beginning to walk using parallel bars, complications affecting treatment, and mortality rate. The 6-month follow-up rate was 54.4% (n = 124). The results showed that the patients with trochanteric fracture were significantly older than those with neck fracture (86 vs. 82 years, respectively; p = 0.03). In total, 85.0% of patients with trochanteric fracture and 92.2% of patients with neck fracture were independent ambulators before injury (FAC score of 4 or 5). The FAC score 6 months after fracture was positively correlated with the FAC score before fracture and at discharge (all p<0.001) and negatively correlated with patient age (p<0.001) and presurgical duration for patients with neck fracture (p = 0.04). There was no statistically significant correlation with the length of hospital stay or the time until beginning to walk using parallel bars. In conclusion, patients with trochanteric fractures were older than those with neck fractures. In both fracture types, walking recovery 6 months after hip fracture was related to the FAC score before injury and at discharge from an acute-care hospital but not to the time until beginning to walk using parallel bars.

Kinematic, kinetic, and musculoskeletal modeling analysis of gait in patients with cervical myelopathy using a severity classification.

BACKGROUND CONTEXT: Although a few reports have shown a change in gait motion in cervical myelopathy (CM) patients using a three-dimensional (3D) gait analysis system, there has been no detailed quantitative investigation of their gait including musculoskeletal modeling parameters. Also, 3D gait analysis using a classification of severity has not been substantiated. PURPOSE: This study aimed to investigate kinematic, kinetic, and musculoskeletal modeling parameters of gait motion in CM patients using a severity classification. STUDY DESIGN: Prospective cohort and cross-sectional study. PATIENT SAMPLE: Forty-two patients with CM and 40 healthy, age-matched volunteers. OUTCOME MEASURES: Lower extremity spatiotemporal, kinematic, kinetic, and musculoskeletal modeling parameters. METHODS: Subjects were classified as to its severity using the Japan Orthopaedic Association score excluding the upper extremity items: group 1 (>10 points); group 2 (7-9 points); and group 3 (<6 points). A 3D motion analysis system and musculoskeletal modeling software were used to obtain the spatiotemporal, kinematic (the lower extremity joints angles in the sagittal plane), kinetic (the lower extremity joints moment and power in the sagittal plane), and musculoskeletal modeling parameters (the muscle-tendon length and velocity). RESULTS: Genu recurvatum, deteriorated lower-extremity joint motion, and muscle-tendon velocity were observed in severe CM patients (group 3). Muscle-tendon velocities of the long head of the biceps femoris in controls and mild CM patients (groups 1 and 2) showed a bimodal waveform in the negative direction during the initial contact and preswing phases, whereas these characteristics were not present in severe CM patients (group 3). CONCLUSIONS: The strategies of the knee joint moment during gait motion in severe CM patients were different from those of the normal gait pattern. The imbalance between agonist and antagonist muscle tissue during gait could be involved in the occurrence of genu recurvatum. It might be important for CM patients to consider improving the contraction or extension velocity of the biceps femoris muscle during each gait phase from the early stages of symptoms.

Anterior and posterior decompressive surgery for progressive amyotrophy associated with cervical spondylosis: a retrospective study of 51 patients.

OBJECT: The aims of this study were to review the clinicoradiological findings in patients who underwent decompressive surgery for proximal and distal types of muscle atrophy caused by cervical spondylosis and to discuss the outcome and techniques of surgical intervention. METHODS: Fifty-one patients (43 men and 8 women) with proximal (37, with arm drop) and distal muscle atrophy (14, with wrist drop) underwent cervical decompression (39 anterior decompressions and 12 open-door C3-7 laminoplasties with microsurgical foraminotomy) for muscle weakness in the upper extremities. The clinical course, type of spinal cord compression, abnormal signal intensity on high-resolution MR imaging, and postdecompression improvement in muscle power were reviewed at a mean follow-up of 2.6 years (range 0.8-9.4 years). RESULTS: The most commonly affected vertebrae were C4-5 and C5-6, and C5-6 and C6-7 in patients with proximal or distal muscle atrophy, respectively; the respective numbers of affected vertebrae were 1.5 and 2.2. Transaxial MR imaging showed medial compression of the spinal cord in 20 patients (in 12 with proximal and 8 with distal muscle atrophy), paramedial compression in 22 (17 and 5 patients, respectively), and foraminal compression in 9 (8 and 1 patient, respectively). Increased signal intensity on MR imaging was observed in 85.0, 22.7, and 11.1% of cases of medial, paramedial, and foraminal compression, respectively. Increased signal intensity at the affected muscle segment level was observed in 52.9, 40.0, and 0% of cases, respectively. Sixty-two percent of patients with proximal muscle atrophy gained 1 or more grades of muscle power on manual muscle testing (MMT), whereas 64.3% with distal muscle atrophy failed to gain even 1 grade of improvement. The recovery of muscle power correlated with disease duration and the percent voltage of Erb point or wrist-stimulated muscle evoked potentials but not with preoperative MMT, longitudinal range of spinal cord compression, signal change on T2-weighted MR imaging, or surgical procedure. CONCLUSIONS: Surgical outcome in patients with distal muscle atrophy was inferior to that in patients with proximal atrophy. The distal type was characterized by a long preoperative period, a greater number of cervical spine misalignments, a narrow spinal canal, and increased signal intensity on T2-weighted MR imaging. It is essential to perform a careful neurological evaluation, including sensory examination of the lower limbs, as well as neuroradiological and neurophysiological assessments to avoid confusion with motor neuron disease and to detect the coexistence of amyotrophic lateral sclerosis, especially when surgical treatment of cervical spondylosis is planned. The results of careful physical examination, MR imaging studies, and electromyography studies should be comprehensively evaluated to ascertain the pathophysiology of the muscle atrophy. It is very important to distinguish the pathophysiology caused by nerve root impingements from anterior horn dysfunction when making decisions about treatment strategy. Surgical treatment--with or without foraminotomy--for amyotrophy in cervical spondylosis requires urgent action with regard to human neuroanatomy and neural innervation of the paralyzed muscles.

Direct detection of pathogens in osteoarticular infections by polymerase chain reaction amplification and microarray hybridization.

BACKGROUND: Molecular biological techniques such as the polymerase chain reaction (PCR) and DNA microarray are used for the detection/identification of microorganisms; however, few reports have discussed the clinical utility of microarray analysis for identification of causative organisms of osteoarticular infections. It is important to examine the utility of PCR amplification followed by analysis of DNA microarray carrying specific oligonucleotides. METHODS: This study included 101 biological samples obtained from 96 patients who underwent conservative and/or surgical treatment for osteoarticular infections. In this double-blind comparative study, routine conventional testing and the research groups were unaware of each other's interpretation until identical specimens were identified by culture and microarray analysis. RESULTS: Results of PCR microarray analysis were positive for 25 samples and negative for the remaining 76 samples within 24 h, and the results of the cultures (available after a mean of 3.54 days) were positive in 26 samples and negative for the remaining 75 samples. The sensitivity of microarray analysis was 84.6% (22/26) and specificity was 88.0% (22/25). Discrepant results were identified in seven samples, including a negative culture and a positive microarray in three cases and a positive culture and a negative microarray in four other cases. CONCLUSIONS: The PCR microarray analysis is complementary to routine cultures in identifying causative microorganisms and should be used in patients with highly suspected infections and negative bacterial culture and in patients who require prompt diagnosis and early initiation of antibiotic therapy.

Calcium pyrophosphate crystal deposition in the ligamentum flavum of degenerated lumbar spine: histopathological and immunohistological findings.

We investigated the histological and immunohistochemical features of degenerative changes in the ligamentum flavum of the lumbar spine with calcium crystal deposition. We investigated degenerative changes in 270 ligamentum flavum specimens harvested from 198 patients who underwent decompressive surgeries for lumbar spinal canal stenosis. En bloc sections of the ligamentum flavum were examined histologically. We also examined immunoreactivity for transforming growth factor (TGF)-beta, vascular endothelial growth factor (VEGF), CD34, and CD68; immunoblot analysis for VEGF; and terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate nick end-labeling (TUNEL) method. The ligamentum flavum showed fragmented and disorganized elastic fiber bundles with increased collagen fibrils in the matrix. Calcium deposition, which was identified as calcium pyrophosphate dihydrate crystals, was evident in 72 of 198 patients and in 99 of 270 samples, and was associated with appearance of hypertrophic chondrocytes and new blood vessel formation. Areas of calcium deposits were surrounded by abundant hypertrophic chondrocytes (with marked immunoreactivity to TGF-beta and VEGF) and a significant number of TUNEL-positive chondrocytes. Calcium crystal deposition in the lumbar ligamentum flavum progresses with reduction in elastic fibers and accumulation of collagen fibrils in the matrix as well as expansion of chondrometaplastic areas.