Objectives. In order to elucidate the influence of sympathetic nerves on lumbar radiculopathy, we investigated whether sympathectomy attenuated pain behaviour and altered the electrical properties of the dorsal root ganglion (DRG) neurons in a rat model of lumbar root constriction. Methods. Sprague-Dawley rats were divided into three experimental groups. In the root constriction group, the left L5 spinal nerve root was ligated proximal to the DRG as a lumbar radiculopathy model. In the root constriction + sympathectomy group, sympathectomy was performed after the root constriction procedure. In the control group, no procedures were performed. In order to evaluate the pain relief effect of sympathectomy, behavioural analysis using mechanical and thermal stimulation was performed. In order to evaluate the excitability of the DRG neurons, we recorded action potentials of the isolated single DRG neuron by the whole-cell patch-clamp method. Results. In behavioural analysis, sympathectomy attenuated the mechanical allodynia and thermal hyperalgesia caused by lumbar root constriction. In electrophysiological analysis, single isolated DRG neurons with root constriction exhibited lower threshold current, more depolarised resting membrane potential, prolonged action potential duration, and more depolarisation frequency. These hyperexcitable alterations caused by root constriction were significantly attenuated in rats treated with surgical sympathectomy. Conclusion. The present results suggest that sympathectomy attenuates lumbar radicular pain resulting from root constriction by altering the electrical property of the DRG neuron itself. Thus, the sympathetic nervous system was closely associated with lumbar radicular pain, and suppressing the activity of the sympathetic nervous system may therefore lead to pain relief

Osteoarthritis (OA) affects the whole joint and leads to chronic pain. The sympathetic nervous system (SNS) seems to be involved in OA pathogenesis, as indicated by in vitro studies as well as by our latest work demonstrating that sympathectomy in mice results in increased subchondral bone volume in the OA knee joint. We assume that chronic stress may lead to opposite effects, such as an increased bone loss in OA due to an elevated sympathetic tone. Therefore, we analyzed experimental OA progression in mice exposed to chronic stress. OA was induced in male C57BL/6J mice by surgical destabilization of the medial meniscus (DMM) and Sham as well as non-operated mice served as controls. Half of these groups were exposed to chronic unpredictable mild stress (CUMS). After 12 weeks, chronic stress efficiency was assessed using behavioral tests. In addition to measuring body weight and length, changes in subchondral bone were analyzed by μCT. Dynamic Weight Bearing system was used to monitor OA-related pain. Histological scoring will be conducted to investigate the severity cartilage degeneration and synovial inflammation. CUMS resulted in increased anxiety and significant decrease in body weight gain in all CUMS groups compared to non-CUMS groups. CUMS also increased serum corticosterone in healthy mice, with even higher levels in CUMS mice after DMM surgery. CUMS had no significant effect on subchondral bone, but subarticular bone mineral density and trabecular thickness were increased. Moreover, CUMS resulted in significant potentiation of DMM-associated pain. Our results suggest that the autonomic imbalance with increased sympathetic nervous activity induced by chronic stress exacerbates the severity of OA pain perception. We expect significantly increased cartilage degeneration as well as more severe synovial inflammation in CUMS DMM mice compared to DMM mice

The December 2014 Spine Roundup. 360 . looks at: surgeon outcomes;. complications and scoliosis surgery; is sequestrectomy enough in lumbar disc prolapse?; predicting outcomes in lumbar disc herniation; sympathectomy has a direct effect on the dorsal root ganglion; and distal extensions of fusion in adolescent idiopathic scoliosis

Osteoarthritis (OA) is a highly prevalent degenerative joint disorder characterized by joint pain and physical disability. Aberrant subchondral bone induces pathological changes and is a major source of pain in OA. In the subchondral bone, which is highly innervated, nerves have dual roles in pain sensation and bone homeostasis regulation. The interaction between peripheral nerves and target cells in the subchondral bone, and the interplay between the sensory and sympathetic nervous systems, allow peripheral nerves to regulate subchondral bone homeostasis. Alterations in peripheral innervation and local transmitters are closely related to changes in nociception and subchondral bone homeostasis, and affect the progression of OA. Recent literature has substantially expanded our understanding of the physiological and pathological distribution and function of specific subtypes of neurones in bone. This review summarizes the types and distribution of nerves detected in the tibial subchondral bone, their cellular and molecular interactions with bone cells that regulate subchondral bone homeostasis, and their role in OA pain. A comprehensive understanding and further investigation of the functions of peripheral innervation in the subchondral bone will help to develop novel therapeutic approaches to effectively prevent OA, and alleviate OA pain.

Cite this article: Bone Joint Res 2022;11(7):439–452.

Anterior stabilisation has been shown to be superior in the treatment of the lumbar and thoraco-lumbar scoliosis, both in regard to the correction of the curves and to the number of fused vertebrae. Since 1995, with the emergence of third-generation locking devices, we have extended the indication of anterior fixation to double major scoliosis with lumbar predominance, operating exclusively on the lumbar curve and allowing the thoracic curve to correct itself. We report this experience with respect to 12 patients. The patients consisted of 11 girls and one boy, mean age 16.6 years (range 12–29). The mean preoperative Cobb angle was: lumbar: 51° (41–72), dorsal 28° (range 21–45). All patients showed a lateral deviation of the trunk with asymmetry of the lumbar region. Of the 12 patients, 11 received stabilisation by EUROS instruments from D11 to L3 and one from D10 to L3. The mean follow-up is 44 months (range 15–77 months). A vertebral fusion was achieved for 94 % of the spaces (46/49). In the fixation zone, a 72% correction rate was achieved, whereas in the non-treated zone of the dorsal rachis, the rate of spontaneous correction was 32 %. In total the angle loss has been on average 4°. The study assessed the horizontal position of the disk underlying the zone of the arthrodesis; in other words the L3 – L4 disk showed the presence of an average gradient angle of 7° with a range from 0° to 17°. No post-operative complications were observed, but 7 of 12 patients have had immediate and transient sympathectomy after-effects, with a modification of the ipsilateral limb temperature at the level of the instrumental access site. Anterior stabilization of the thoracolumbar curve in double major scoliosis with lumbar predominance seems to be preferred to posterior correction. This technique, by preserving the posterior musculature, makes it possible to save from 1 to 2 disk downwards. In turn, this makes it possible to correct the lateral translation and the realignment of the trunk starting with fusion limited to the lumbar spine. It is imperative to avoid hypercorrection of the thoraco-lumbar curve and even leave a bit of curve in the in situ modelling of the rod. Then the lumbar curve can be balanced with the dorsal curve and avoid an increase in the lumbosacral counter-curve with the risk in of rotatory dislocation in adult age. Since we have started using this technique, we have not had to perform double correction, anterior and posterior, for double major scoliosis with lumbar predominance