Combining the Physical-Chemical Approach with Standard Base Excess to Understand the Compensation of Respiratory Acid-Base Derangements: An Individual Participant Meta-analysis Approach to Data from Multiple Canine and Human Experiments.

BACKGROUND: Several studies explored the interdependence between Paco2 and bicarbonate during respiratory acid-base derangements. The authors aimed to reframe the bicarbonate adaptation to respiratory disorders according to the physical-chemical approach, hypothesizing that (1) bicarbonate concentration during respiratory derangements is associated with strong ion difference; and (2) during acute respiratory disorders, strong ion difference changes are not associated with standard base excess. METHODS: This is an individual participant data meta-analysis from multiple canine and human experiments published up to April 29, 2021. Studies testing the effect of acute or chronic respiratory derangements and reporting the variations of Paco2, bicarbonate, and electrolytes were analyzed. Strong ion difference and standard base excess were calculated. RESULTS: Eleven studies were included. Paco2 ranged between 21 and 142 mmHg, while bicarbonate and strong ion difference ranged between 12.3 and 43.8 mM, and 32.6 and 60.0 mEq/l, respectively. Bicarbonate changes were linearly associated with the strong ion difference variation in acute and chronic respiratory derangement (ß-coefficient, 1.2; 95% CI, 1.2 to 1.3; P < 0.001). In the acute setting, sodium variations justified approximately 80% of strong ion difference change, while a similar percentage of chloride variation was responsible for chronic adaptations. In the acute setting, strong ion difference variation was not associated with standard base excess changes (ß-coefficient, -0.02; 95% CI, -0.11 to 0.07; P = 0.719), while a positive linear association was present in chronic studies (ß-coefficient, 1.04; 95% CI, 0.84 to 1.24; P < 0.001). CONCLUSIONS: The bicarbonate adaptation that follows primary respiratory alterations is associated with variations of strong ion difference. In the acute phase, the variation in strong ion difference is mainly due to sodium variations and is not paralleled by modifications of standard base excess. In the chronic setting, strong ion difference changes are due to chloride variations and are mirrored by standard base excess.

Combined traumatic atlantooccipital and atlantoaxial articulation instability: a case report with survival.

Traumatic atlantooccipital dislocation is a rare injury in survivors with 15 % share in deaths due to spinal injury. The authors present a case of a patient with concurrent atlantooccipital and atlantoaxial instability of the upper cervical spine, which he suffered after a fall from height. Atlantooccipital dislocation in surviving patients is a rare injury, for which in some cases coincident bone injury is reported to upper cervical spine, such as occipital fracture or contingent odontoid (C2 dens) fracture. In our case, it is combined with atlantoaxial instability and this combined type of injury has not yet been described in the literature. We performed realignment of the dislocation and posterior occipitocervical (C0-C3) fusion. After the surgery, the patient manifested neurological improvement almost to a normal neurological outcome with persistent residual finding after subarachnoid hemorrhage.

Quantifying pH-induced changes in plasma strong ion difference during experimental acidosis: clinical implications for base excess interpretation.

It is commonly assumed that changes in plasma strong ion difference (SID) result in equal changes in whole blood base excess (BE). However, at varying pH, albumin ionic-binding and transerythrocyte shifts alter the SID of plasma without affecting that of whole blood (SIDwb), i.e., the BE. We hypothesize that, during acidosis, 1) an expected plasma SID (SIDexp) reflecting electrolytes redistribution can be predicted from albumin and hemoglobin's charges, and 2) only deviations in SID from SIDexp reflect changes in SIDwb, and therefore, BE. We equilibrated whole blood of 18 healthy subjects (albumin = 4.8 ± 0.2 g/dL, hemoglobin = 14.2 ± 0.9 g/dL), 18 septic patients with hypoalbuminemia and anemia (albumin = 3.1 ± 0.5 g/dL, hemoglobin = 10.4 ± 0.8 g/dL), and 10 healthy subjects after in vitro-induced isolated anemia (albumin = 5.0 ± 0.2 g/dL, hemoglobin = 7.0 ± 0.9 g/dL) with varying CO2 concentrations (2-20%). Plasma SID increased by 12.7 ± 2.1, 9.3 ± 1.7, and 7.8 ± 1.6 mEq/L, respectively (P < 0.01) and its agreement (bias[limits of agreement]) with SIDexp was strong: 0.5[-1.9; 2.8], 0.9[-0.9; 2.6], and 0.3[-1.4; 2.1] mEq/L, respectively. Separately, we added 7.5 or 15 mEq/L of lactic or hydrochloric acid to whole blood of 10 healthy subjects obtaining BE of -6.6 ± 1.7, -13.4 ± 2.2, -6.8 ± 1.8, and -13.6 ± 2.1 mEq/L, respectively. The agreement between ΔBE and ΔSID was weak (2.6[-1.1; 6.3] mEq/L), worsening with varying CO2 (2-20%): 6.3[-2.7; 15.2] mEq/L. Conversely, ΔSIDwb (the deviation of SID from SIDexp) agreed strongly with ΔBE at both constant and varying CO2: -0.1[-2.0; 1.7], and -0.5[-2.4; 1.5] mEq/L, respectively. We conclude that BE reflects only changes in plasma SID that are not expected from electrolytes redistribution, the latter being predictable from albumin and hemoglobin's charges.NEW & NOTEWORTHY This paper challenges the assumed equivalence between changes in plasma strong ion difference (SID) and whole blood base excess (BE) during in vitro acidosis. We highlight that redistribution of strong ions, in the form of albumin ionic-binding and transerythrocyte shifts, alters SID without affecting BE. We demonstrate that these expected SID alterations are predictable from albumin and hemoglobin's charges, or from the noncarbonic whole blood buffer value, allowing a better interpretation of SID and BE during in vitro acidosis.

Perimortem dynamics of blood potassium concentration in patients dying in intensive care unit: A prospective nested cohort study.

To enable diagnosis of hyperkalemia from the perimortem blood sample, we aim to describe the natural dynamics of blood potassium [K+ ] in patients dying after withdrawal of care while in an intensive care unit. In a nested sub-study of international Death Prediction and Physiology after Removal of Therapy (DePPaRT) project, we obtained serial whole-blood samples and analyzed ions and acid-base parameters in 23 patients just before life-sustaining treatment withdrawal, at the time of death, and after 5 and 30 min after death. Of the 631 patients in the DePPaRT study, we obtained consent and enrolled 23 subjects in the [K+ ] sub-study (12 M, 11F, aged 73 ± 14 years), mostly dying from irreversible brain damage or multi-organ failure. Blood [K+ ] rose from the median 4.3 (IQR 3.9; 4.8) mEq/L at treatment withdrawal to 5.2 (IQR 5.0; 6.8) mEq/L at death and then to 5.85 (IQR 5.2; 6.8) mEq/L after 30 min (mean rise of +0.64 mEq.L-1 .h-1 ). These changes were associated with progressive lactic and hypercapnic acidemia. After correcting the measured [K+] for pH by subtracting 0.6 mEq/L from [K+] for every 0.1 pH decrease from 7.40, the calculated [K+] remained normal or decreased from that measured at treatment withdrawal. In contrast to the late autolysis phase, the early changes of blood [K+ ] after death are slow and can be fully explained by progressive acidemia. Our data suggest that the diagnosis of hyperkalemia at death from a blood sample obtained within 30 min after death can be made by adjusting the [K+] concentration to a pH 7.40.

Determination of stress and displacement on human composite pelvis under static and dynamic loading.

This case study describes the experimental determination of displacements and stresses on a composite model of a pelvis that was modified to represent a healthy intact pelvic ring. The modified model was stressed statically up to 1750 N to simulate standing on one leg and also cyclically to model walking. For two different model settings in the loading machine the values of displacements and stresses at the pelvic ring were determined. The two different settings correspond to two different loading vectors applied on the pelvic ring, boundary conditions and degrees of freedom. The experimentally determined values of displacements in both settings are very similar and in accordance with the knowledge on the behaviour of a real human pelvis. The modified model is thus suitable for testing of newly developed implants for pelvis treatment and experimental determination of displacements and stresses in pelvic ring which are caused by application of implants.

Alteration of cortical but not spinal inhibitory circuits in idiopathic scoliosis.

Background: The pathogenesis of adolescent idiopathic scoliosis (AIS), including the role of brain and spinal inhibitory circuits, is still poorly elucidated. The aim of this study was to identify which central inhibitory mechanisms are involved in the pathogenesis of AIS.Design: A prospective neurophysiological study, using a battery of neurophysiological tests, such as cutaneous (CuSP) and cortical (CoSP) silent periods, motor evoked potentials (MEP) and paired-pulse transcranial magnetic stimulation (ppTMS).Settings: Neurophysiological laboratory.Participants: Sixteen patients with AIS (14 females, median age 14.4) and healthy controls.Outcome measures: MEPs were obtained after transcranial magnetic stimulation (TMS) and recorded from the abductor pollicis muscle (APB). ppTMS was obtained at interval ratios (ISI) of 1, 2, 3, 6, 10, 15 and 20 ms. The cortical silent period (CoSP) was recorded from the APB. The cutaneous silent period (CuSP) was measured after painful stimuli delivered to the thumb while the subjects maintained voluntary contraction of the intrinsic hand muscles. The data were analyzed and compared with those from healthy subjects.Results: The CoSP duration was significantly prolonged in AIS patients. A significantly higher amplitude of ppTMS for ISI was found in all AIS patients, without remarkable left-right side differences. No significant difference in MEP latency or amplitude nor in the CuSP duration was obtained.Conclusion: Our observation demonstrates evidence of central nervous system involvement in adolescent idiopathic scoliosis (AIS). Lower intracortical inhibition, higher motor cortex excitability, and preserved spinal inhibitory circuits are the main findings of this study. A possible explanation of these changes could be attributed to impaired sensorimotor integration predominantly at the cortical level.

Non-carbonic buffer power of whole blood is increased in experimental metabolic acidosis: An in-vitro study.

Non-carbonic buffer power (ßNC) of blood is a pivotal concept in acid-base physiology as it is employed in several acid-base evaluation techniques, including the Davenport nomogram and the Van Slyke equation used for Base excess estimation in blood. So far, ßNC has been assumed to be independent of metabolic acid-base status of blood, despite theoretical rationale for the contrary. In the current study, we used CO2 tonometry to assess ßNC in blood samples from 10 healthy volunteers, simultaneously analyzing the electrolyte shifts across the red blood cell membrane as these shifts translate the action of intracellular non-carbonic buffers to plasma. The ßNC of the blood was re-evaluated after experimental induction of metabolic acidosis obtained by adding a moderate or high amount of either hydrochloric or lactic acid to the samples. Moreover, the impact of ßNC and pCO2 on the Base excess of blood was examined. In the control samples, ßNC was 28.0 ± 2.5 mmol/L. In contrast to the traditional assumptions, our data showed that ßNC rose by 0.36 mmol/L for each 1 mEq/l reduction in plasma strong ion difference (p < 0.0001) and was independent of the acid used. This could serve as a protective mechanism that increases the resilience of blood to the combination of metabolic and respiratory acidosis. Sodium and chloride were the only electrolytes whose plasma concentration changed relevantly during CO2 titration. Although no significant difference was found between the electrolyte shifts in the two types of acidosis, we observed a slightly higher rate of chloride change in hyperchloremic acidosis, while the variation of sodium was more pronounced in lactic acidosis. Lastly, we found that the rise of ßNC in metabolic acidosis did not induce a clinically relevant bias in the calculation of Base excess of blood and confirmed that the Base excess of blood was little affected by a wide range of pCO2.

Unilateral isolated dislocation at the lumbosacral junction: lateral flexion-distraction as a major vector in the mechanism of injury: case report and trauma mechanism analysis.

The description of the unusual mechanism of the trauma to lumbosacral junction is given based on the analysis of the clinical case. The injury of a patient with unilateral dislocation at the L5-S1 intervertebral joint without a bone lesion in this segment is reported. The patient suffered the injury by falling on one side from a height of 8 m. The trauma mechanism is documented by MRI findings and a 3D CT reconstruction of the paravertebral muscles and soft tissues on the injured side, whilst showing intact structures on the contralateral side. This, together with the cause of injury (a fall on the side), provides evidence for forced lateral flexion-distraction being the major vector of the trauma event. Such mechanism of this injury was not taken in account by other authors yet. This type of injury is difficult to classify using the Magerl classification system. The very rare injury has been mentioned in the literature only occasionally.

The role of vascularization on changes in ligamentum flavum mechanical properties and development of hypertrophy in patients with lumbar spinal stenosis.

BACKGROUND CONTEXT: Ligamentum flavum (LF) induced lumbar spinal stenosis (LSS) is conditioned not only by its "gathering" but especially by hypertrophy. Previous studies have examined the pathophysiology and biochemical changes that cause the hypertrophy. Some studies have described a link between chronic LF inflammation and neovascularization but others have reported highly hypovascular LF tissue in LSS patients. Currently, there is no practical application for our knowledge of the pathophysiology of the LF hypertrophy. Considerations for future treatment include influencing this hypertrophy at the level of tissue mediators, which may slow the development of LSS. To our knowledge, there is no study of micromechanical properties of native LF to date. PURPOSE: (1) To clarify the changes in vascularization, chondroid metaplasia, and the presence of inflammatory cell infiltration in LF associated with LSS. (2) To quantify changes in the micromechanical properties associated with LF degenerative processes. STUDY DESIGN/SETTING: Vascular density analysis of degenerated and healthy human LF combined with measurement of micromechanical properties. METHODS: The study involved 35 patients who underwent surgery between November 1, 2015 and October 1, 2016. The LSS group consisted of 20 patients and the control group consisted of 15 patients. LF samples were obtained during the operation and were used for histopathological and nanoindentation examinations. Sample vascularization was examined as microvascular density (Lv), which was morphometrically evaluated using semiautomatic detection in conjunction with NIS-Elements AR image analysis software. Samples were also histologically examined for the presence of chondroid metaplasia and inflammation. Mechanical properties of native LF samples were analyzed using the Hysitron TI 950 TriboIndenter nanomechanical testing system. RESULTS: Vascular density was significantly lower in the LSS group. However, after excluding the effect of age, the difference was not significant. There was high association between Lv and age. With each increasing year of age, Lv decreased by 11.5 mm2. Vascular density decreased up to the age of 50. Over the age of 50, changes were no longer significant and Lv appeared to stabilize. No correlation was observed between Lv and the presence of inflammation or metaplasia; however, LSS patients had a significantly increased incidence of chondroid metaplasia and inflammatory signs. The mechanical properties of control group samples showed significantly higher stiffness than those samples obtained from the LSS group. CONCLUSION: This study showed that Lv changes were not dependent on LSS but were age-dependent. Vascular density was found to decrease up to the age of 50. A significantly higher incidence of chondroid metaplasia and inflammation was observed in LSS patients. The mechanical property values measured by nanoindentation showed high microstructural heterogeneity of the tested ligaments. Our results showed that healthy ligaments were significantly stiffer than LSS ligaments. CLINICAL SIGNIFICANCE: Prevention of the loss of LF vascularization during aging may influence stiffness of LF which in turn may slow down the LF degenerative processes and delay onset of LSS.

Biomechanical comparison of cemented versus non-cemented anterior screw fixation in type II odontoid fractures in the elderly: a cadaveric study.

BACKGROUND CONTEXT: Odontoid process fractures are the most common injuries of the cervical spine in the elderly. Anterior screw stabilization of type II odontoid process fractures improves survival and function in these patients but may be complicated by failure of fixation. PURPOSE: The present study aimed to determine whether cement augmentation of a standard anterior screw provides biomechanically superior fixation of type II odontoid fractures in comparison with a non-cemented standard screw. STUDY DESIGN: Twenty human cadaveric C2 vertebrae from elderly donors (mean age 83 years) were obtained. METHODS: Anderson and D'Alonzo type IIa odontoid fracture was created by transverse osteotomy, and fluoroscopy-guided anterior screw fixation was performed. The specimens were divided into two matched groups. The cemented group (n=10) had radiopaque high viscosity polymethylmethacrylate cement injected via Jamshidi needle into the base of the odontoid process. The other group was not augmented. A V-shaped punch was used for loading the odontoid in an anteroposterior direction until failure. The failure state was defined as screw cutout or 5% force decrease. Mean failure load and bending stiffness were calculated. RESULTS: The mean failure load for the cemented group was 352±12 N compared with 168±23 N for the non-cemented group (p<.001). The mean initial stiffness of the non-cemented group was 153±19 N/mm compared with 195±29 N/mm for the cemented group (p<.001) CONCLUSIONS: Cement augmentation of an anterior standard screw fixation of type II odontoid process fractures in elderly patients significantly increased load to failure under anteroposterior load in comparison with non-augmented fixation. This may be a valuable technique to reduce failure of fixation.

Antithrombotic therapy of patients with atrial fibrillation discharged after major non-cardiac surgery. 1-year follow-up. Sub-analysis of PRAGUE 14 study.

BACKGROUND: The study investigated the discharge antithrombotic medication in patients with atrial fibrillation (AF) after major non-cardiac surgery and the impact on one-year outcomes. METHODS: A subgroup of 366 patients (mean age 75.9±10.5 years, women 42.3%, acute surgery 42.9%) undergoing major non-cardiac surgery and having any form of AF (30.6% of the total population enrolled in the PRAGUE-14 study) was followed for 1 year. RESULTS: Antithrombotics (interrupted due to surgery) were resumed until discharge in 51.8% of patients; less frequently in men (OR 0.6 (95% CI 0.95 to 0.35); p = 0.029), and in patients undergoing elective surgery (OR 0.6 (95% CI 0.91 to 0.33); p = 0.021). Dual antiplatelet therapy was resumed more often (91.7%) in comparison to aspirin monotherapy (57.3%; p = 0.047), and vitamin K antagonist (56.3%; p = 0.042). Patients with AF had significantly higher one-year mortality (22.1%) than patients without AF (14.1%, p = 0.001). The causes of death were: ischaemic events (32.6% of deaths), bleeding events (8.1%), others (N = 51; 59.3%, 20 of them died due to cancer). Non-reinstitution of aspirin until discharge was associated with higher one-year mortality (17.6% vs. 34.8%; p = 0.018). CONCLUSION: Preoperatively interrupted antithrombotics were re-administrated at discharge only in half of patients with AF, less likely in male patients and those undergoing elective surgery. The presence of AF was recognized as a predictor of one-year mortality, especially if aspirin therapy was not resumed until discharge. TRIAL REGISTRATION: ClinicalTrials.gov NCT01897220.

Etiopathogenesis of adolescent idiopathic scoliosis: Expression of melatonin receptors 1A/1B, calmodulin and estrogen receptor 2 in deep paravertebral muscles revisited.

The pathogenesis of adolescent idiopathic scoliosis (AIS), including the associated local changes in deep paravertebral muscles, is poorly understood. The asymmetric expression of several molecules involved in the melatonin signaling pathway, including melatonin receptors 1A/1B (MTNR1A/MTNR1B), estrogen receptor 2 (ESR2) and calmodulin (CALM1), has previously been suggested to be associated with AIS. However, this hypothesis is based on single studies in which the data were obtained by different methodological approaches. Therefore, to evaluate the symmetry of the mRNA expression levels of these molecules, 18 patients with AIS and 10 non­scoliotic controls were enrolled in the present study. Muscle biopsy samples from deep paraspinal muscles (from the convexity and concavity of the scoliotic curve in patients with AIS, or from the left and right sides in controls) were obtained during spinal surgery. For each sample, the relative mRNA expression levels of MTNR1A, MTNR1B, CALM1 and ESR2 were analyzed by reverse transcription­quantitative polymerase chain reaction (RT­qPCR) and were quantified according to the quantification cycle method. The results indicated that the mRNA expression levels of none of the investigated molecules were significantly different between samples obtained from the convex and concave side of the scoliotic curve in patients with AIS. In addition, no difference in expression was detected between the patients with AIS and the controls. With regards to MTNR1A and MTNR1B, their expression was very weak in paravertebral muscles, and in the majority of cases their expression could not be detected by repeated RT­qPCR analysis. Therefore, these data do not support the previously suggested role of the asymmetric expression of molecules involved in the melatonin signaling pathway in deep paravertebral muscles in the pathogenesis of AIS.

Distal locking in short hip nails: Cause or prevention of peri-implant fractures?

OBJECTIVES: The most common cause of femoral fractures after osteosynthesis of trochanteric fractures with short nails is weakening of the femoral cortex via distal locking and stress concentrations at the tip of the nail. The aim of the study was to verify whether the incidence of peri-implant fractures is dependent upon the distal locking technique. METHODS: We prospectively analysed a group of 849 pertrochanteric fractures (AO/ASIF 31-A1+2) managed with short nails from 2009 to 2013. Unlocked nailing was performed in 70.1% and distal dynamic locking was performed in 29.9%. The mean age was 82.0 years. Peri-implant fractures were divided into 3 groups according to the height of the fracture in relation to the tip of the nail. RESULTS: In total 17 fractures (2.0%) were detected. One peri-implant fracture occurred after locked nailing, whereas 16 cases occurred after unlocked nailing (p=0.037). Patients without distal locking had an 85.7% greater risk of peri-implant fracture. Fractures of the proximal femur (Type I) occurred significantly earlier than fractures at the tip of the nail (Type II) (p=0.028). CONCLUSION: Unlocked nails do not guarantee sufficient stability. Distal locking serves to prevent postoperative femoral fractures. We recommend the routine use of distal locking when utilizing short nails.

Distal tibiofibular synostosis after surgically resolved ankle fractures: An epidemiological, clinical and morphological evaluation of a patient sample.

INTRODUCTION: Ankle fractures comprise a highly morphologically and etiologically diverse group of injuries, which includes various degrees of impairment of bone and ligamentous structures. The complete synostosis and incomplete bony bridging of tibiofibular syndesmosis are among the local late complications after surgically treated ankle fractures. PATIENTS AND METHOD: 269 patients were evaluated, including 203 patients with Weber type-B fractures, and 66 patients with Weber type-C fractures. All patients underwent ankle radiography at standard intervals (post-operatively, 6 and 12 weeks, 6 and 12 months). The final assessment one year after osteosynthesis was performed. The study analyzed age, sex, fracture morphology, the location and morphology of ossification, functional outcomes and subjective evaluations of patient status. RESULTS: As risk factors there were found male sex, tibiotalar dislocation, syndesmotic screw fixation and Weber type-C fractures. The severity of subjective difficulties and objective status were not dependent on the size of distal tibiofibular synostosis. DISCUSSION AND CONCLUSION: Despite relatively extensive imaging findings of complete synostosis or incomplete bony bridging, they only limited functional outcomes to a minimal extent.

The role of the autonomic nervous system in the etiology of idiopathic scoliosis: prospective electron microscopic and morphometric study.

OBJECTS: The exact etiology of scoliosis is still unknown. The main purpose of this study is to search for the possible causation of scoliosis in the development changes of autonomic nervous structures. In this prospective study, we followed-up the changes in peripheral nerve structures and its discrepancies regarding the concavity and convexity of the scoliotic curve. MATERIALS AND METHODS: We evaluated 12 patients with the idiopathic scoliotic deformity and the control group of 3 patients without any scoliotic deformity. The samples from the peripheral nerves of the convexity and concavity of the scoliotic deformity were drawn during the surgical correction by using the transthoracic approach. The samples were examined by the electron microscopic method and morphometric statistical evaluation. RESULTS: In samples taken from the scoliotic convexity, 23.71% of myelinized nerve fibers (MNF), 12.21% of unmyelinized nerve fibers (UNF), and 5.0% of Schwann cells (SC) were found by the morphometric measurement. There were 17.36% of MNF, 5.82% of UNF, and 5.27% of SC in samples taken from the concavity and 29.9% of MNF, 19.9% of UNF, and 16.7% of SC in the control nonscoliotic samples. Statistically significant differences between both sides of scoliotic deformity (convexity and concavity) and differences between the scoliotic samples and the nonscoliotic control samples were found. In all scoliotic samples, significant morphologic changes were found, mostly in the myelin sheaths and axon fiber abnormalities compression. CONCLUSION: There are significant morphologic changes in spinal autonomic nervous structures in scoliotic patients. These findings can help us in the search for the etiology of scoliosis.

Approaches to spondylotic cervical myelopathy: conservative versus surgical results in a 3-year follow-up study.

STUDY DESIGN: A 3-year prospective randomized study was conducted. OBJECTIVE: To compare conservative and operative treatments of mild and moderate, nonprogressive, and slowly progressive forms of spondylotic cervical myelopathy. SUMMARY OF BACKGROUND: DATA It is not known whether the results of decompressive surgery for the mild and moderate forms of spondylotic cervical myelopathy are any better than those of the conservative approach. METHODS: For this study, 68 patients were randomized into two groups. Group A, treated conservatively, consisted of 35 subjects, whereas Group B, treated surgically, was composed of 33 patients. The clinical outcome was evaluated by modified JOA score, timed 10-m walk, the score for daily activities recorded by video and evaluated by two observers blinded to the type of therapy, and subjective assessment by the patients themselves at months 6, 12, 24, and 36 of the follow-up period. RESULTS: There was, on the average, no significant deterioration in mJOA score in the two groups over the 3-year follow-up period, but there was a slightly expressed decrease in the self-evaluation score in Group B, and a slight deterioration of the score for daily activities in Group A. Comparison of the two groups showed a significant difference in the timed 10-m walk test favoring group A, but no difference in mJOA score or self-evaluation by the patients themselves, with the exception of a better score at month 6 in favor of Group B. CONCLUSIONS: The 3-year follow-up study did not show, on the average, that the surgery is superior to conservative treatment for mild and moderate forms of spondylotic cervical myelopathy.