Effect of Therapeutic Exercise on the Activation of the Neck Extensors in People With Chronic Neck Pain
Condition: Neck Pain
MeSH terms: Neck Pain
Study type: Interventional

Summary: 
      The primary aim of this study therefore is to investigate the effects on pain and disability
      of an emphasized exercise program targeting the deep neck extensor semispinalis cervicis and
      a general exercise program for all neck extensor muscles in patients with chronic neck pain.
      As a secondary aim , pain intensity (VAS), cervical ROM, pressure pain threshold (PPT),
      cervical and thoracic posture and self-perceived benefit of treatment (GROC) were measured.
      The investigators hypothesized that both exercise programs would have similar effects on pain
      alleviation and pain related disability, but that the emphasized exercise program for the
      deep semispinalis cervicis would improve its activation more compared to the general exercise
      program. The results of this study will be relevant for designing effective
      rehabilitation/training programs for patients with chronic neck pain.
    

Detailed description: 
      An independent group, repeated-measures study design was adopted to investigate the immediate
      effect of two different kinds of intervention: Emphasized exercises targeting the deep
      cervical extensors and general exercises targeting all neck extensors. Subjects were
      randomized into two exercise groups: the emphasized exercise group in which patients
      performed muscle contractions against resistance directly at the neck and the general
      exercise group in which the resistance was applied at the head. Sealed opaque envelopes were
      used to conceal allocation.

      Exercise regimes was of 6-weeks duration and started within one week of the initial
      assessment. All subjects received personal instruction and supervision by one experienced
      physiotherapist, once a week, for the duration of the whole program.

      Subjects received an exercise diary and were requested to practice their respective regime
      twice per day for the six-week duration of the trial, without provoking neck pain and with
      attention to correct performance of the exercises. Exercises at home occurred for a period of
      no longer than 15 to 20 minutes twice per day. Subjects were asked not to seek other
      interventions for neck pain during the duration of the study, although usual medication was
      not withheld.

      All patients performed two static exercises and one dynamic exercise. The only difference
      between both groups was the location of the resistance, which was in the lower cervical spine
      approximately at level C4 for the emphasized exercise group and at the occiput for the
      general exercise group.

        1. Patients in the emphasized exercise group performed exercises emphasizing the deep
           cervical extensor muscles applying a resistance at the level of the vertebral arch of C4
           either therapeutically with the therapist's fingers or as a home exercise with the aid
           of a towel or belt. These exercises were performed in sitting and standing in front of a
           table propped up on both forearms. In the latter position, a dynamic exercise was added
           moving the head from maximal flexion to maximal extension keeping the gaze fixed at an
           object lying between both elbows hoping to activate more the extensors in the lower
           cervical spine.

        2. Patients in the general exercise group performed exercises targeting all cervical
           extensor muscles including the superficial ones applying resistance at the head pushing
           against a wall or the therapist's hand or as a home exercise with the aid of a towel. As
           in the other group, these exercises were performed in sitting and standing in front of a
           table propped up on both forearms. In the latter position, the same dynamic exercise was
           added as in the other group with the only difference that the gaze was fixed at an
           object lying between both hands hoping to activate all cervical extensors.

      The dosage for both exercise regimes required maximal muscle activation of the patient
      because it was shown that at this dosage the emphasized exercise results in muscle activation
      of about 20% to 25% MVC (Maximum Voluntary Contraction) and the general exercise of about 50%
      MVC (Schomacher et al., 2015). Patients were asked therefore to perform the exercises at
      their individual maximal force for a short time without provoking any pain neither during nor
      after the exercise. That is, submaximal effort without evoking pain during and after the
      exercises was used.

      All exercises were repeated each for 3 sets with a break of 1-2 minutes between the sets. The
      two static exercises consisted of 6 repetitions of 6 seconds hold in each position with 6
      seconds rest between each contraction. The dynamic exercise was performed with 6 repetitions
      through the whole range of motion with 2-3 seconds for each repetition without any rest
      between the repetitions. A break between the repetitions was added if necessary to avoid pain
      (Table 1). Patients repeated the exercise session one time per week under supervision of a
      physiotherapist, during 6 weeks. In addition, patients performed the exercise session twice
      per day seven days per week at home. Each exercise session lasted about 20 - 25 minutes.
    

Intervention name(s): Static exercise for emphasized neck extensors; Dynamic exercise for emphasized neck extensors; Static exercise for general neck extensors; Dynamic exercise for general neck extensors
Intervention type(s): Procedure; Procedure; Procedure; Procedure
Intervention description(s): Emphasized activation of the deep neck extensors was searched for applying a localized resistance with the thumb and index finger at the level of the vertebral arch of C4 while pushing into flexion in a ventral-cranial direction, approximately parallel to the surface of the zygapophyseal joint, asking the patient to resist maximally during 6 seconds in sitting position; The patient was asked to fix his gaze at an object lying between both elbows hoping to in order to emphasize extension in the lower cervical spine and consequently activation of the extensors in this region.; Emphasized activation of all neck extensors was searched for applying the resistance with the therapist's hand or a wall respectively a towel at the occiput in sitting position; . The patient was asked to fix his gaze at an object lying between both hands. Extension consequently occurred in the entire cervical spine.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment
Keywords: Therapeutic exercise; Chronic pain; Neck extensors