OBJECTIVETo study the effect of disc degeneration on the structural property distributions in the cervical vertebral endplates.

METHODSA 2 mm-diameter hemispherical indenter was used to perform indentation tests at 0.03 mm/s to the depth of 2 mm at 20 normalized locations in 50 bony endplates of intact human cervical vertebrae (C2 approximately C7). The resulting load-displacement curves were used to extract the failure load and stiffness of each test site. Grade of disc degeneration was determined using Nachemson's grading scale. One-way ANOVA, factorial analyses, SNK tests and correlate analyses were used to analyze the result data.

RESULTSBoth the failure load and stiffness decreased with disc degeneration in the cervical endplates (P <0.001, both), and correlated significantly with the disc degeneration (rs=-0.429 and rs=-0.244, respectively). Only the distribution of superior cervical endplate changed with disc degeneration, but that of inferior cervical endplate changed little.

CONCLUSIONSThe structural property distributions in the cervical vertebral endplates change significantly in the degenerated discs. It suggests that disc degeneration is an important factor to evaluate the intervertebral implant subsidence in anterior cervical fusion.

Biomechanical Phenomena ; Cervical Vertebrae ; physiopathology ; Compressive Strength ; physiology ; Humans ; Intervertebral Disc ; physiology ; Intervertebral Disc Displacement ; physiopathology ; Weight-Bearing ; physiology

As a common disease in clinical, the treatment of lumbar disc herniation (LDH) focused on local intervertebral disc, such as surgery and other interventional therapy treatment, but postoperative complications and recurrence rate has been a difficult problem in the field of profession. With the development of spine biomechanics and anatomy, researches on lumbar herniation also increased. Researchers discovered that the incidence and prognosis of LDH were inseparable with local muscle and soft tissue. As the deep paraspinal muscles, multifidus muscle plays an important role to make lumbar stability. Its abnormal function could reduce the stable of lumbar spine, and the chronic lumbar disease could also lead to multifidus muscle atrophy.
Animals ; Humans ; Intervertebral Disc Displacement ; physiopathology ; surgery ; Lumbosacral Region ; physiopathology ; surgery ; Paraspinal Muscles ; physiopathology

OBJECTIVETo study the biomechanical relationship between iliac rotation displacement and L(4,5) disc degeneration, and to provide clinical evidences for the prevention and treatment of L(4,5) disc degeneration and herniation.

METHODSFrom March 2012 to February 2014,68 patients with lumbar disc herniation combined with sacroiliac joint disorders were selected. Among them, 42 patients with L(4,5) disc herniation combined with sacroiliac joint disorders included 22 males and 20 females, ranging in age from 19 to 63 years old, with an average of (51.78 +/- 20.18) years old, and the duration of the disease ranged from 1 to 126 months with an average of (11.18 +/- 9.23) months. Twenty-six patients with L5S1 disc herniation combined with sacroiliac joint disorders included 11 males and 15 females, ranging in age from18 to 65 years old with an average of (45.53 +/- 27.23) years old, and the duration of the disease ranged from 0.5 to 103 months with an average of (11.99 +/- 12.56) months. Sixty-eight anteroposterior lumbar radiographs, 68 lateral lumbar radiographs,and 68 pelvic plain films were taken. The degree of lumbar scoliosis, pelvic tilt,and disc thickness were measured. The correlation between pelvic tilt and lumbar scoliosis ,lumbar scoliosis and disc thickness were studied by using linear and regression methods. The hiomechanical analysis was performed.

RESULTSThere was a positive correlation between pelvic tilt and lumbar scoliosis in patients with L(4,5) disk herniation (R=0.49, P=0.00). There was a causal relationship and good linear proportional relationship (Y=3.05+1.07X, P=0.00) in the two variables. There was a negative correlation between lumbar scoliosis and intervertebral space in male patients with L (4,5) disk herniation (R = -0.50, P=0.01). There was a causal relationship and good linear proportional relationship in the two variables (Y=13.09-0.27X, P=0.02). But there was a positive correlation between lumbar scoliosis and intervertebral space in male patients with L5S1 disk herniation (R=0.46, P=0.04).

CONCLUSIONIliac rotational displacement are closely related with L(4,5) disc degeneration and herniation in biomechanics. A new concepts and therapeutic approach is provided for clinical treatment of chronic and refractory herniation of L(4,5) disc in patients

Adult ; Biomechanical Phenomena ; Female ; Humans ; Intervertebral Disc Degeneration ; physiopathology ; Intervertebral Disc Displacement ; physiopathology ; Lumbar Vertebrae ; physiopathology ; Male ; Rotation ; Sacroiliac Joint ; chemistry ; physiopathology ; Young Adult

OBJECTIVETo investigate the operative management and surgical techniques for lumber disc herniation (LDH) in aged patients (>or=65 years).

METHODSFrom 2005 to 2010,the data of 43 patients with LDH underwent surgical treatment were retrospectively analyzed. There were 25 males and 18 females,aged from 65 to 70 years old with an average of 67.6 years. The course of disease was from 6 weeks to 7 years with an average of 10.2 years. Fenestratiodn discectomy or extended fenestration discectomy and unilateral or bilateral fenestration were used according to the conditions of location,type of herniated macleos polposus and nerve root compression. Among the patients,the nerve root canal was enlarged,hyperplastic osteophyma and soft tissue were removed, bilateral articular process was reserved in order to maintain the stability of the lumbar segment.

RESULTSAll the patients were followed up from 1.2 to 5.2 years. According to the criteria of HU you-gu, 25 cases got excellent results, 15 good, 2 fair and 1 poor. No infection or nerve injury was found. Nerve function of patients had a normal or near normal recovery.

CONCLUSIONFor the treatment of LDH in aged patents,it is key that reasonably choose the operative method, completely remove the hyperplasy of diseased region and enlarge the nerve root canal, thoroughly loose the nerve root.

Aged ; Female ; Humans ; Intervertebral Disc Displacement ; physiopathology ; surgery ; Lumbar Vertebrae ; surgery ; Male ; Retrospective Studies

It is rather popular of spinal manipulative therapy (SMT) in the west as well as it is in the east. Along with the fast developing of modem medicine in the past decade, the mechanism of SMT showed many different ideas in the Eastern and Western countries. The recent study on the mechanism of SMT in Western countries had widely focused on aspect of the stress reaction of joint and neurobiological effect of manipulative loading. Method of study involved in immunohistochemical, anatomic, nerve myoelectrical aspects and so on. The results have showed the two sides of SMT from many aspects and challenged our belief if we could have it systematically integrated into modern medicine along with the deep understanding continuing progressed. We could positively learn something from the studies and absorb some constructive viewpoints of their analysis by the review.
Analgesia ; Animals ; Biomechanical Phenomena ; Humans ; Intervertebral Disc Displacement ; physiopathology ; Manipulation, Spinal ; methods ; Reflex

OBJECTIVETo investigate the effects of spinal manipulation (SM) on brain functional activity in patients with lumbar disc herniation (LDH).

METHODSEleven patients with LDH were recruited in the study. All patients received 6 times of lumbar SM treatment and then clinical efficacy was evaluated. All patients received brain functional magnetic resonance imaging (fMRI) scans before and after SM treatment.

RESULTSThree subjects dropped out and 8 subjects completed the study, among whom 4 cases were effective and 4 ineffective after SM treatment. The required pressure value producing the same level (VAS 50) pain was (7.43 ± 1.47) kg and (10.53 ± 0.55) kg before and after SM treatment in effective patients(P<0.05); however, there was no significant difference in ineffective patients (P>0.05). Compared to pre-treatment level, the brain functional activity in effective patients was mainly inhibited, the inhibited areas were located in the right side of prefrontal cortex and cerebellum; while the brain functional activity was generally enhanced in ineffective patients.

CONCLUSIONSM can affect the brain functional activity of patients with LDH, the inhibited areas is mainly located in prefrontal cortex and cerebellum when SM treatment is effective.

Brain ; physiopathology ; Humans ; Intervertebral Disc Displacement ; therapy ; Lumbar Vertebrae ; pathology ; Magnetic Resonance Imaging ; Manipulation, Spinal

OBJECTIVETo explore clinical presentations and the operational opportunity of traumatic cervical disc herniation.

METHODSFrom June 2002 to June 2009,40 patients with traumatic cervical disc herniation were treated. There were 24 males and 16 females, with an average age of 43.2 years old ranging from 30 to 56 years. There were 36 patients with single intervertebral disc herniation and 4 patients with double. The injury level of those patients were at C3,4 in 16 cases, C4,5 in 10 cases, C5,6 in 12 cases and C6,7 in 6 cases. Among them, 18 patients showed spinal cord signal changes by MRI, 5 patients suffered from nothing but neck and shoulder pain, 8 patients with nerve root stimulation; 10 patients with spinal cord compression, and 17 patients had both nerve root stimulation and spinal cord compression symptoms. Conservative treatment were applied to 13 patients with neck and shoulder pain and nerve root stimulation, 5 cases of which were transferred to operation in case of poor effects, and Odom criteria were used to assess operational effects. Twenty-seven patients with spinal cord compression accepted operation from 1 to 27days after their trauma, 16 of which were operated in 5 days (early operational group with an JOA score of 11.3 +/- 2.8), other 11 cases were operated from 5 to 27 days (delayed operational group with an JOA score of 11.4 +/- 2.9 ), then functional assessment of spinal cord were assessed according to JOA criteria.

RESULTSThree patients who were transferred from conservative treatment recovered excellently according to Odom criteria and the other 2 were good at final followed-up. JOA score of early operational group increased from (11.3 +/- 2.8) to (15.3 +/- 1.8) one week after operation (P < 0.01), and (15.9 +/- 1.4) at final followed-up (P < 0.01). JOA score of delayed operational group increased from (11.4 +/- 2.9) to (14.0 +/- 2.6) one week after operation (P < 0.01), and (15.3 +/- 1.5) at final followed-up (P < 0.01). The recovery ratio of JOA score of early operational group were (74.6 +/- 16.8)% 1 week after operation,and increased to (85.6 +/- 13.6)% at final followed-up; while that of delayed operational group were (50.9 +/- 17.5)% and (68.2 +/- 21.5)%, and there were significant difference between early operational group and delayed operational group both at 1 week postoperation and final followup (P < 0.05).

CONCLUSIONThere are some difference in pathological segment and imaging manifestation between traumatic cervical disc herniation and cervical spondylosis. Early operation is favorable to the recovery of neurological function in patients with spinal cord compression.

Adult ; Cervical Vertebrae ; injuries ; surgery ; Female ; Humans ; Intervertebral Disc Displacement ; physiopathology ; surgery ; Male ; Middle Aged

Dynamic stabilization system plays an important role in the treatment of the degenerative lumbar spine. Fusion of short movement segments has little influences on the motion of lumbar spine. Meanwhile, preservation of movements of segment can prevent the degeneration of adjacent segment and maintain the possibility of disc replacement even under the condition that facet joints need to be excised. While maintaining the normal lumbar motion, dynamic stabilization system can not only decrease the load of intervertebral disc of corresponding movement segments and provide a good environment for the recovery of intervertebral disc and soft tissues, but also delay the degeneration of small facet and reconstruct the biomechanical function of spine.
Biomechanical Phenomena ; Humans ; Intervertebral Disc Displacement ; surgery ; Low Back Pain ; physiopathology ; surgery

OBJECTIVETo apply needle-knife to treat lumber disc herniation (LDH) and surface electromyography were used to analyze biomechanical characteristic of patient's lumber muscle to make a comprehensive evaluation on its efficacy.

METHODSThirty patients who met the inclusive criteria were selected and treated with needle-knife, once a week for 2 weeks. Visual analogue scale (VAS), ASLR and JOA score before and after treatment were observed. Surface electromyography was applied to test the surface electromyography signals. AEMG, MFs and MPF were calculated before and after the treatment.

RESULTSAfter treatment, VAS was significantly reduced, ASLR, JOA, AEMG and MPF were obviously increased, and the absolute value of MFs was lowed (all P < 0.01).

CONCLUSIONThe needle-knife could significantly relieve lumbar muscle strength, muscle tone and muscle fatigue, improve in the imbalance of lumbar extensor muscle group, leading to the recovery of biomechanical characteristic, and the clinical efficacy is superior.

Acupuncture Therapy ; Adult ; Electromyography ; Female ; Humans ; Intervertebral Disc Displacement ; diagnosis ; physiopathology ; therapy ; Lumbar Vertebrae ; physiopathology ; Male ; Middle Aged

OBJECTIVE: To evaluate the mechanical properties of artificial lumbar intervertebral disc by finite-element (FE) analysis, to predict the mechanical influence of loading on the prosthesis after placement, especially after the long-term employment,and to offer the mechanical basis and technological means for the design optimization. METHODS: A 3-dimensional solid model was built according to the geometry of the prosthesis; finite-element analysis was applied to determine the effect of the implanted artificial disc prosthesis on the biomechanical behavior; and the data of its mechanical responses were calculated in 3 compression modes which simulated its different load conditions in vivo. Simulations were conducted in a new specially designed manner, preferably simulated load conditions in vivo. RESULTS: A finite-element model was established by generating mesh out of the prosthesis geometry. The analysis was conducted in employing models of the disc prosthesis under 3 types of emulational realism loading conditions, obtaining the distributing characteristics and data of displacement-stress-strain-energy in the structure, which are difficult to measure exactly by conventional methods. CONCLUSION Implanted loading strongly influences prosthesis in its internal distribution of displacement-stress-strain-energy in the structure, suggesting that the disc prosthesis allows correctly reproducing a profitable motion and cushion at the implanted level. Predictive wear may occur in special parts according to the designed prosthesis mechanical structure. When implanting an artificial disc, proper size should be taken in choosing disc and the higher core could provide better mechanical characteristics. The Results may assist in optimizing artificial lumbar disc replacement primarily from a biomechanical point of view.
Biomechanical Phenomena ; Computer Simulation ; Finite Element Analysis ; Humans ; Intervertebral Disc ; Intervertebral Disc Displacement ; etiology ; pathology ; physiopathology ; Lumbar Vertebrae ; physiology ; Models, Biological ; Prostheses and Implants ; Stress, Mechanical ; Weight-Bearing ; physiology