The Stabilizing System of the Spine. Part II. Neutral Zone and Instability Hypothesis

Department of Orthopaedics and Rehabilitation, Yale University School of Medicine, New Haven, Connecticut 06510.
Journal of Spinal Disorders (Impact Factor: 1.21). 01/1993; 5(4):390-6; discussion 397. DOI: 10.1097/00002517-199212000-00002
Source: PubMed


The neutral zone is a region of intervertebral motion around the neutral posture where little resistance is offered by the passive spinal column. Several studies--in vitro cadaveric, in vivo animal, and mathematical simulations--have shown that the neutral zone is a parameter that correlates well with other parameters indicative of instability of the spinal system. It has been found to increase with injury, and possibly with degeneration, to decrease with muscle force increase across the spanned level, and also to decrease with instrumented spinal fixation. In most of these studies, the change in the neutral zone was found to be more sensitive than the change in the corresponding range of motion. The neutral zone appears to be a clinically important measure of spinal stability function. It may increase with injury to the spinal column or with weakness of the muscles, which in turn may result in spinal instability or a low-back problem. It may decrease, and may be brought within the physiological limits, by osteophyte formation, surgical fixation/fusion, and muscle strengthening. The spinal stabilizing system adjusts so that the neutral zone remains within certain physiological thresholds to avoid clinical instability.

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    • "A slouched posture is a kind of abnormal sitting posture with flexed lumbar spine occurs during day-to-day sitting activities [12] [13]. As a result of this prolonged flexed posture, if extends for a long time, the neutral position is lost and the spine is potentially exposed to injury [14] [15]. Although the etiology of LBP is complex and multifactorial, an incorrect sitting posture could play a relevant role in determining both an increase of stress within the disc [16] [17] and a sustained stretch of passive lumbar structures in combination with poor back muscle activity [18]. "
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    ABSTRACT: Objective: This study aimed to find out the effectiveness of multiple therapeutic intervention combinations to manage Postural Low back pain among the Information Technology [IT] Professionals. Study design: The randomized control study design. Materials and Methods: All the subjects (N=90) were randomized into three groups which consists of one control and two experimental groups. The subjects in the Experimental group I were given Motor Control Training and Ergonomic Training whereas the Experimental group II were given Myofascial Release, Motor Control Training and Ergonomic Training was given for a period of 6 weeks that includes first 3 weeks of Myofascial Release along with Motor Control Training and Ergonomic Training, further the Motor Control Training and Ergonomic Training was continued for the period of 4 to 6 weeks duration. The subjects in the control group were not given any therapeutic modalities throughout the study. The effectiveness of the therapeutic interventions were measured through three outcome parameters such as Back pain intensity, Back pain disability and Transversus Abdominis muscle strength. The Analysis of Covariance and Scheffe’s post hoc tests were applied to study the treatment effectiveness. The effectiveness of the therapeutic intervention at three different time intervals was also analyzed using repeated measures ANOVA and if found significant, a Newman Keul’s post hoc tests was employed to study the significance between two time intervals. Results & Conclusion: The results of this study concluded that the Experimental group-II is found to be better than Experimental group-I and Control group in the reduction of Low Back pain intensity, Back pain disability and Transversus Abdominis muscle strength of the Software professionals with Postural low back pain. KEY WORDS: Postural Low back pain, Myofascial Release, Information Technology employees, Ergonomic Training, Motor Control Training.
    Full-text · Article · Dec 2015 · International Journal of Physiotherapy and Research
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    • "The neutral zone, defined as the region of minimal passive stiffness (Panjabi, 1992), has been used to standardize the test posture of functional spinal units (FSUs) for in vitro biomechanical studies (Balkovec & McGill, 2012; Callaghan & McGill, 2001; Gooyers, McMillan, Howarth, & Callaghan, 2012; "

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    • "In the current work we study a novel conservative treatment performed primarily with active specialized manual therapy ( " hands on " ) named the POLD Concept (Pulsation Oscillation Long Duration) (L opez Díaz, 2005; L opez Díaz, 2012). This method is an evolution of rhythmic oscillating mobilization (Maitland, 2007) with the following differential aspects: (1) the oscillatory movement has a " sinusoidal " waveform, (2) resonant oscillation frequency is used between 1.2 and 2 Hz, (3) oscillation is maintained throughout treatment and is called primary oscillation, (4) very small amplitude (less than grade 1 according to Maitland) within the " neutral zone " (Panjabi, 1992) are used. "
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    ABSTRACT: This study analyses the efficacy of manual oscillatory therapy, following the POLD technique, for acute Lumbar Disc Hernia (LDH) and compares it to usual treatment. A randomised, controlled, triple-blind pilot clinical trial. The sample of 30 patients was divided into two homogeneous groups to receive usual treatment (A) or treatment with the POLD technique (B). We analysed range of motion and subjective variables such as the severity (visual analogue pain scale (VAS)) and extension of the pain. With the application of POLD therapy, patients presented significant changes on range of motion (forward flexion with p < 0.05) at completion of the trial in comparison with the control group. They showed a significant reduction in the severity of pain with a mean VAS scale for lumbar, glutaeus and thigh pain, which improved from 5.09 to 0.79, 5.07 to 0.97 and 4.43 to 0.49 respectively (p < 0.05), and also when compared to usual treatment (p < 0.05) for all body regions. Moreover, we observed a reduction in pain extension (centralization phenomena) (p < 0.001) in comparison with usual treatment.
    Full-text · Article · Nov 2014 · Manual Therapy
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