Impact of deep brain stimulation therapy on the vertebral sagittal balance in Parkinson's disease patients

Parkinson's disease (PD) is characterized by cardinal motor signs: 4-6 Hz resting tremor, rigidity, and bradykinesia. In addition, 3-18% of PD patients have camptocormia, an abnormal forward flexion of the thoracolumbar spine, which may have a negative impact on patients' quality of life. Different possible treatments have been suggested for such a condition, but no one is resolutive. This study aims to define the possible impact of DBS, with selective targeting on the dorsal-lateral region of the STN, on the sagittal balance of patients affected by PD. Among all patients that have undergone DBS procedures in our institution, we selected eight subjects, four females and four males, with selective targeting on the dorsal-lateral region of the subthalamic nucleus (STN) because of camptocormia and other severe postural changes. Radiological assessments of spinal balance parameters before surgery and at 6 and 12 months postoperatively were carried out. Comparison of preoperative and postoperative spine X-ray data showed a statistically significant improvement in dorsal kyphosis angle (D-Cobb) 12 months after the operation. Deep brain stimulation with selective targeting of the dorsal lateral part of the STN may induce changes of the posture in patients with Parkinson's disease 12 months after the operation, which appears to improve in this small sample size, but larger observational and controlled trials would be required to confirm this observation.

Association of sagittal spinal alignment in the standing position with the masses and amounts of intramuscular non-contractile tissue of the trunk and lower extremity muscles in patients with Parkinson's disease

BACKGROUND

We examined the association of sagittal spinal alignment in the standing position with the masses and amounts of intramuscular non-contractile tissue of multiple trunk and lower extremity muscles, such as the hip joint muscles, measured using an ultrasound imaging device in patients with Parkinson's disease (PD).

METHODS

The participants were 10 patients with PD. Sagittal spinal alignment (thoracic kyphosis, lumbar lordosis, and sacral anterior inclination angles) in the standing position was measured using a Spinal Mouse. Muscle thicknesses and echo intensities of the trunk and lower extremity muscles, including the hip joint muscles, were also measured in the prone or supine position using an ultrasound imaging device.

FINDINGS

Partial correlation analysis with body height and weight as control variables showed that a low lumbar lordosis angle in the standing position was significantly associated with low thicknesses of the trunk extensor muscles (lumbar erector spinae and multifidus). Partial correlation analysis also revealed that a high sacral anterior inclination angle in the standing position was significantly associated with low lumbar multifidus muscle thickness. However, the thicknesses and echo intensities of the trunk flexor and hip joint muscles were not significantly related to thoracic kyphosis, lumbar lordosis, or sacral anterior inclination angles.

INTERPRETATION

The results of this study suggested the association between a low lumbar lordosis angle in the standing position and low lumbar erector spinae and multifidus muscle thicknesses and between a high sacral anterior inclination angle in the standing position and low lumbar multifidus muscle thickness in patients with PD.

Technology-based therapy-response evaluation of axial motor symptoms under daily drug regimen of patients with Parkinson’s disease

Background

Axial disturbances are the most disabling symptoms of Parkinson’s disease (PD). Kinect-based objective measures could extract motion characteristics with high reliability and validity.

Purpose

The present research aimed to quantify the therapy–response of axial motor symptoms to daily medication regimen and to explore the correlates of the improvement rate (IR) of axial motor symptoms based on a Kinect camera.

Materials and methods

We enrolled 44 patients with PD and 21 healthy controls. All 65 participants performed the Movement Disorder Society-Sponsored Revision of the Unified Parkinson’s Disease Rating Scale part III and the Kinect-based kinematic evaluation to assess arising from a chair, gait, posture, and postural stability before and after medication. Spearman’s correlation analysis and multiple linear regression model were performed to explore the relationships between motor feature IR and clinical data.

Results

All the features arising from a chair (P = 0.001), stride length (P = 0.001), velocity (P < 0.001), the height of foot lift (P < 0.001), and turning time (P = 0.001) improved significantly after a daily drug regimen in patients with PD. In addition, the anterior trunk flexion (lumbar level) exhibited significant improvement (P = 0.004). The IR of the axial motor symptoms score was significantly correlated with the IRs of kinematic features for gait velocity, stride length, foot lift height, and sitting speed (r_s = 0.345, P = 0.022; r_s = 0.382, P = 0.010; r_s = 0.314, P = 0.038; r_s = 0.518, P < 0.001, respectively). A multivariable regression analysis showed that the improvement in axial motor symptoms was associated with the IR of gait velocity only (β = 0.593, 95% CI = 0.023–1.164, P = 0.042).

Conclusion

Axial symptoms were not completely drug-resistant, and some kinematic features can be improved after the daily medication regimen of patients with PD.

Gait Characteristics and Brain Activity in Parkinson's Disease with Concomitant Postural Abnormalities

To explore the underlying pathogenic mechanism of Parkinson's disease (PD) with concomitant postural abnormalities (PDPA) through the relationship between its gait and brain function characteristics. PD patients from the neurology outpatient clinic at Ruijin Hospital were recruited and grouped according to whether postural abnormalities (including camptocormia and Pisa syndrome) were present. PD-related scale assessments, three-dimensional gait tests and brain resting-state functional magnetic imaging were performed and analyzed. The gait characteristics independently associated with PDPA were decreased pelvic obliquity angle and progressive downward movement of the center of mass during walking. PDPA features included decreased functional connectivity between the left insula and bilateral supplementary motor area, which was significantly correlated with reduced Berg Balance Scale scores. Functional connectivity between the right insula and bilateral middle frontal gyrus was decreased and significantly correlated with a decreased pelvic obliquity angle and poor performance on the Timed Up and Go test. Moreover, through diffusion tensor imaging analysis, the average fractional anisotropy value of the fibers connecting the left insula and left supplementary motor area was shown to be decreased in PDPA. There is decreased functional connectivity among the insula, supplementary motor area and middle frontal gyrus with structural abnormalities between the left insula and the left supplementary motor area; these changes in brain connectivity are probably among the causes of gait dysfunction in PDPA and provide some clues regarding the pathogenic mechanisms of PDPA.

The Study of Subthalamic Deep Brain Stimulation for Parkinson Disease-Associated Camptocormia

BACKGROUND Camptocormia is an axis symptom of Parkinson disease. It remains uncertain whether treatment with medications and surgery are effective. In this study, we assessed the efficacy of subthalamic nucleus deep brain stimulation (STN DBS) in Parkinson disease-associated camptocormia and explored some of its mechanisms. MATERIAL AND METHODS Parkinson disease-associated camptocormia was diagnosed by the following procedures. All patients underwent bilateral STN DBS. The patents' camptocormia was rated by degree and MDS Unified Parkinson's Disease Rating Scale (UPDRS) item 3.13 before and after DBS surgery. Rehabilitation and psychological interventions were used after surgery, in addition to adjustments of medication and stimulus parameters. The treatment effects on camptocormia were assessed comparing medication-off (presurgery) versus stimulation-on (post-surgery). Ethical approval for this study was provided through the Center of Human Research Ethics Committee (No. 2019-35). This study trial was registered in Chinese Clinical Trial Registry (No. ChiCTR1900022655). All the participants provided written informed consent. RESULTS After DBS surgery, all of study patients' symptoms were improved, with different levels of improvement. The minimum and maximum improvement rates were 20% and 100% respectively. The score of item 3.13 of the MDS-UPDRS III and the degree of camptocormia were found to be obviously improved (P<0.05). CONCLUSIONS STN DBS can improve Parkinson disease-associated camptocormia; STN DBS assisted with rehabilitation and psychological intervention appears to be more effective.

Immediate effect of spinal magnetic stimulation on camptocormia in Parkinson's disease

OBJECTIVES

Spinal cord stimulation is a potential therapeutic option for the treatment of Parkinson's disease (PD)-associated symptoms. Repetitive trans-spinal magnetic stimulation (rTSMS) is a non-invasive and safe alternative for stimulation of spinal pathways that has not been studied for therapeutic efficacy in PD. We assessed the benefits of rTSMS on camptocormia, an often treatment-resistant postural abnormality observed in PD patients.

METHODS

We compared rTSMS to sham stimulation in PD patients with camptocormia in a single-centre, randomised, single-blind, crossover, placebo-controlled study. PD patients with camptocormia were administered a single trial of rTSMS (a train of 40 stimuli) or sham treatment followed 1 week later by the alternate treatment. Primary outcome measure was thoracolumbar spine flexion angle in the standing position immediately after the trial.

RESULTS

Of 320 PD patients examined, 37 had concomitant camptocormia and were randomly assigned to either the rTSMS first group (n=19) or sham first group (n=18). Flexion angle in the standing position decreased by a mean of 10.9° (95% CI 8.1 to 13.65) after rTSMS but remained unchanged after sham stimulation (mean, -0.1°; 95% CI -0.95 to 0.71). The flexion angle while sitting (secondary outcome) decreased by 8.1° (95% CI 5.89 to 10.25) after rTSMS, whereas sham treatment had no significant effect (mean, -0.8°; 95% CI -1.62 to 0.05).

CONCLUSIONS

We found an immediate beneficial effect of rTSMS on camptocormia in PD patients. Although the effect was transient, this successful trial justifies further studies to test if repeated rTSMS treatments can induce longer term improvements in camptocormia associated with PD.

CLINICAL TRIAL REGISTRATION

UMIN Clinical Trials Registry: UMIN000011495.

Motor outcome of dystonic camptocormia treated with pallidal neurostimulation

BACKGROUND

Deep brain stimulation of the internal pallidum (GPi-DBS) is effective for various types of drug-refractory primary dystonias. Rare clinical forms as dystonic camptocormia may profit but available data are scarce.

METHODS

We here report on a retrospective clinical assessment of three patients with primary dystonic camptocormia treated with GPi-DBS.

RESULTS

All three patients showed marked response to bilateral GPi-DBS within days to weeks after surgery which was preserved in the long-term (38-45 months after implantation: mean improvement 82% as rated on the Burke Fahn Marsden Dystonia Rating Scale, 89% in the subitem "trunk"). Two patients developed mild stimulation induced speech problems (stuttering or dysarthria) which resolved with reprogramming or were acceptable in return for the control of dystonic symptoms.

CONCLUSIONS

The diagnosis and treatment of camptocormia will continue to require expert knowledge in movement and neuromuscular disorders, but DBS may expand treatment options in this difficult patient population.

[Causes of camptocormia]

In this society with an ever increasing number of the elderly there is an increasing number of causes of a bent spine syndrome (camptocormia/dropped head syndrome). The causes include neurological, neuro-orthopedic, rheumatological and psychiatric disorders. Parkinson's disease, dystonia and neuromuscular diseases (motor neuron disease, myositis and muscular dystrophy) with weakness of the axial muscles may result in bent spine syndrome and is often combined with a dropped head. Disc herniation, hypertrophic spondylosis or pseudospondylolisthesis with spinal narrowing may lead to an abnormal flexion of the trunk. Ankylosing spondylitis can produce a disabling bent spine syndrome. Camptocormia may also be mimicked by osteoporotic fractures of the vertebral bones with wedge-shaped vertebrae. In some cases camptocormia is related to a psychogenic disorder.

Anterocollis and camptocormia in parkinsonism: a current assessment

Postural deformities in parkinsonian syndromes are well recognized, but poorly understood and largely refractory to available therapies. In recent times a number of hypotheses have been proposed to explain the underlying etiology of anterocollis and camptocormia, but currently there is no consensus. As these conditions are more precisely characterized we begin to uncover that this is a heterogeneous and evolving phenomenon. These conditions bring to light the inadequacies of our current tools to study biomechanics of posture, neuromuscular disorders, and dystonic muscular contractions. The development of objective, accurate tools to directly study and measure the severity of these postural disorders will allow for further understanding of the pathophysiology, the development of novel therapeutics, and adequate clinical trial design.

Clinical subtypes of anterocollis in parkinsonian syndromes

BACKGROUND

Disproportionate anterocollis is a debilitating condition which occurs in the later stages of parkinsonian syndromes and for which there is no effective therapy. Multiple hypotheses have been proposed to explain its underlying etiology, including myopathy of the cervical extensors, and dystonia of the cervical flexors.

METHODS

We examined the records of 39 patients (8 prospectively) with anterocollis and parkinsonian syndromes to explore demographics, historical and clinical data, findings from electromyography and response to therapies. We classified our patients based on whether or not they were weak on neck extension and also based on primary diagnosis (PD vs atypical parkinsonian syndrome). Demographic, clinical, historical and EMG features are reported for each group.

RESULTS

There were no significant demographic differences between clinical subtypes, or primary diagnosis. Electromyographic (EMG) findings demonstrated myopathic changes in both groups, although they were more prominent in the group which was weak in extension. Historical features were similar between groups except for dopamine agonist use, which was more common in the myopathic subgroup (p=0.02). There were no other significant clinical differences between clinical subtypes or primary diagnosis with the exception that patients with atypical parkinsonian syndromes had more advanced motor symptoms.

CONCLUSIONS

We conclude that anterocollis is a heterogeneous condition in which at least two distinct subtypes exist. Recognizing these subtypes may help guide therapy and future research.