European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society
-
Clinical Trial
Thoracolumbar spinal fractures: segmental range of motion after dorsal spondylodesis in 82 patients: a prospective study.
In order to study the effect of dorsal spondylodesis on intervertebral movement in patients treated for thoracolumbar fractures, we measured the sagittal range of motion (ROM) in the segments above and below the fractured vertebral body 2 years after operation. Between 1991 and 1996, 82 consecutive patients with a fracture of the thoracolumbar spine (T12, L1, L2 and L3) were treated operatively with open reduction and stabilisation using an internal fixator, combined with transpedicular cancellous bone graft and dorsal spondylodesis. Eighteen T12, 42 L1, 17 L2 and 5 L3 fractures were included. ⋯ All other evaluated segments showed significant loss of ROM (P<0.05) compared to normal values, except segment L1-L2 in L3 fractures (P=0.058). Dorsal spondylodesis at the level of the disturbed endplate in thoracolumbar spinal fractures leads to immobility in this segment, measured on flexion-extension radiographs 2 years after primary operative treatment. More than 50% loss of motion in the two adjacent levels is equivalent to complete loss of ROM in a second segment.
-
The purpose of the current study was twofold: (1) to determine the isometric force and electromyographic (EMG) relationship of the sternocleidomastoid, splenii and trapezii muscles bilaterally in graded and maximal exertions in the sagittal, coronal and oblique planes. and (2) to develop regression equations to predict force based on the EMG scores. A newly designed and validated cervical isometric strength testing device was used to measure the cervical muscle isometric strength and force/EMG relationship in cervical flexion, extension, bilateral lateral flexion, bilateral anterolateral flexion, and bilateral posterolateral extension, all beginning with an upright seated neutral posture. A group of 40 healthy subjects were asked to exert their cervical motions in the directions of interest, while the force output and EMG from the sternocleidomastoids, splenii, and trapezii were sampled bilaterally at 1 kHz. ⋯ EMG output was, for example, approximately 66% higher in flexion than in extension (while force output was roughly 30% less in flexion than extension) - thus relatively more muscle activity was required in flexion than extension to generate a given force. The intermediate positions (i.e. anterolateral flexion) revealed force/EMG ratio scores that were intermediate in relation to the force/EMG ratios for pure flexion and pure extension. The cervical muscle strength and cervical muscle EMG are therefore dependent on the direction of effort.
-
The present study was carried out to examine possible mechanisms of back muscle dysfunction by assessing a stabilising and a torque-producing back muscle, the multifidus (MF) and the iliocostalis lumborum pars thoracis (ICLT), respectively, in order to identify whether back pain patients showed altered recruitment patterns during different types of exercise. In a group of healthy subjects (n=77) and patients with sub-acute (n=24) and chronic (51) low back pain, the normalised electromyographic (EMG) activity of the MF and the ICLT (as a percentage of maximal voluntary contraction) were analysed during coordination, stabilisation and strength exercises. The results showed that, in comparison with the healthy subjects, the chronic low back pain patients displayed significantly lower (P=0.013) EMG activity of the MF during the coordination exercises, indicating that, over the long term, back pain patients have a reduced capacity to voluntarily recruit the MF in order to obtain a neutral lordosis. ⋯ During the strength exercises, the normalised activity of both back muscles was significantly lower in chronic low back pain patients (P=0.017 and 0.003 for the MF and ICLT, respectively) than in healthy controls. Pain, pain avoidance and deconditioning may have contributed to these lower levels of EMG activity during intensive back muscle contraction. The possible dysfunction of the MF during coordination exercises and the altered activity of both muscles during strength exercises may be of importance in symptom generation, recurrence or maintenance of low back pain.
-
Nucleus pulposus and/or chronic compression can induce spinal nerve root injury. Inflammation has been proposed as having major importance in the pathophysiologic mechanisms involved in the induction of such injuries. Corticosteroids, potent anti-inflammatory drugs, have been demonstrated to reduce nucleus pulposus-induced spinal nerve root injury. The aim of the present study was to assess the effects of two potent non-steroidal anti-inflammatory drugs (NSAIDs), diclofenac and ketoprofen, in experimental nucleus pulposus-induced spinal nerve root injury in a pig model. ⋯ This study of two potent NSAIDs indicates that nucleus pulposus-induced nerve root dysfunction may be reduced by diclofenac but not by ketoprofen. The reason for this difference is not known, but it might be related to the fact that ketoprofen and diclofenac belong to different NSAID subgroups and have a different selectivity for the two cyclo-oxygenases COX-1 and COX-2.
-
Intradiscal pressure after repeat intradiscal injection of hypertonic saline: an experimental study.
Chemonucleolysis with chymopapain is an effective alternative to an operation for the treatment of some patients who have a lumbar intervertebral disc herniation. However, chymopapain is associated with rare but serious complications. Accordingly, alternative substances for chemonucleolysis have been sought. ⋯ The intradiscal pressure of the group with repeat hypertonic saline injection at 4 weeks was significantly lower than that of the control group. The decreased pressure showed a tendency to increase at 8 weeks, and it had recovered at 12 weeks. The results of this study suggest that repeat hypertonic saline injections may be clinically useful.