Successful physical therapy treatment using high-velocity low-amplitude thrust manipulation of a patient with neck pain scoring sub-optimally on cervical and thoracic clinical prediction rules for manipulative therapy

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Abstract

This case report describes successful outpatient physical therapy intervention (including High Velocity Low Amplitude Thrust (HVLAT) spinal manipulation) of a 43 year-old female patient with neck pain who did not fit ideal clinical prediction rule criteria for thoracic or cervical manipulation following an initial unsuccessful course of physical therapy. Following patient report of “0% improvement” in a physical therapy clinic that did not include HVLAT, patient care was transferred to a different clinic and the patient received physical therapy care that included HVLAT for 10 sessions. During that time, neck disability index scores decreased from 76% to 18%, meeting previously established criteria for minimally detectable change as well as clinically meaningful change. Cranio-cervical flexion test abilities improved from 18mmHg to 28mmHg, active cervical rotation improved from 45 degrees bilaterally to 85 degrees bilaterally, and neck pain had decreased from 7/10 to 0/10 on a Numeric Pain Rating Scale. Functionally, the patient re-acquired the ability to work an 8 hour shift of manual labor, to turn her head and back out of the driveway with her car, and to sleep through the night without waking in pain. The potential relative importance of non-clinical psychosocial factors in the prediction of outcome in patients who do not ideally fit clinical prediction rules is discussed.

Background

Neck pain is a common complaint of patients presenting to physical therapy, with annual incidence estimated as high as 17.9% of the population, estimates of lifetime incidence ranging from 22% to 70% (Croft et al 2001, Cote et al 2004, Palmer et al 2001) and estimates of more than one-third of all patients with neck pain continuing to experience discomfort upon 6 month follow-up (Cote et al 2004). Physical therapy treatment of neck pain varies between therapists and across treatment environments. Although a recent Cochrane review of patients with neck pain suggests similar results in pain reduction, functional improvement and patient satisfaction between mobilization and manipulation (Gross et al 2010) little is known about which factors contribute to optimal results in patients who score sub-optimally on clinical prediction rules. Recent literature has reported statistically relevant variables in the development of each of two clinical prediction rules (CPRs) in the selection and application of either cervical manipulation or thoracic manipulation on patients with neck pain. Tseng et al (2006) discuss a six-factor clinical prediction rule (see Table 1) in attempting to identify immediate responders to cervical manipulation in patients with neck pain.

Although the risk of serious complication from cervical spine manipulation is small in statistical terms(Hurwitz et al 1996, Sweeny and Doody 2010) the paucity of sufficiently sensitive and specific pre-manipulative screening tests to determine which patients may be a risk for serious adverse events following cervical manipulation has caused some authors to advocate against its use in clinical practice (Di Fabio 1999, Halderman et al 2002). Cleland et al (2007) reported 6 statistically relevant variables in an attempt to identify neck pain patients likely to benefit from thoracic spine manipulation (see Table 2), perceived to be a less risky technique.

Table 1- Clinical Prediction Rule: Tseng’s cervical high-velocity low-amplitude thrust manipulation for cervical pain

  • Initial Neck Disability Index Score (NDI) <11.5/50
  • Bilateral patterns of movement dysfunction
  • Not performing sedentary work > 5 hours/day
  • Feeling better while moving the neck
  • Feeling worse while extending the neck
  • Diagnosis of spondylosis without radiculopathy
4/6 factors = 89%

Table 2 – Clinical Prediction Rule: Cleland’s thoracic high-velocity low-amplitude thrust manipulation for cervical pain

  • Symptoms < 30 days
  • No Symptoms Distal to Shoulder
  • Looking up does not aggravate Symptoms
  • Fear Avoidance Behavior Questionnaire – Physical Activity (FABQPA) score < 12/24
  • Decreased upper Thoracic spine kyphosis
  • Cervical extension AROM < 30 degrees
5/6 factors = 100% 4/6 factors = 93% 3/6 factors = 86% 2/6 factors = 71% 1/6 factors = 58%

Although the follow-up study of Cleland’s CPR did not support validation (Cleland 2010), the results did demonstrate that thoracic spine manipulation and exercise exhibited significantly greater improvements in disability, as well as in pain, compared to patients who did not receive spinal manipulation. This result, in addition to the fact that many physical therapists utilize manipulative techniques as their approach of choice with what they perceive to be successful results, suggests the existence of previously undocumented variables of statistical relevance. This case report describes the successful treatment of a patient who met only 2/6 criteria on the Cleland CPR for thoracic spinal manipulation (71%) and who also met only 3/6 criteria on the Tseng CPR for cervical spinal manipulation. Successful outcome was realized with physical therapy that included High Velocity Low Amplitude Thrust (HVLAT) manipulation, following an initial failed course of physical therapy that did not include HVLAT manipulation.

Patient Characteristics

The patient, a 43-year-old female with complaint of 7/10 neck pain and headache on the Numeric Pain Rating Scale (NRPS), was referred for physical therapy at a hospital outpatient facility in central North Carolina following an initial evaluation and several treatment visits provided by a physical therapist at a physician owned physical therapy practice (POPTS). Limited information regarding initial course of care revealed that the patient had been imaged and cleared for physical therapy, prior to initiation of care with POPTS physical therapist. Initial intervention, according to the patient, included stretching, massage, and ultrasound. The patient was then referred by her physician to a clinic that provided HVLAT spinal manipulation, secondary to what the patient and physician described as “lack of progress,” and a “personality conflict,” between the patient and therapist.

Informed consent was once again obtained from the patient prior to her second evaluation course of treatment. At that time, the patient’s neck pain and headache was described as beginning bilaterally in the low-to-middle aspect of the neck, radiating superiorly up the back of the neck and around the ear. The mechanism of injury was a motor vehicle accident (MVA), nearly 2 months prior to her second initial evaluation. Neck Disability Index (NDI) score was 38/50, or 76% disability (defined as “severe disability” by Vernon and Mior (1991)) which exceeded the greater than 11.5 score identified in Tseng’s CPR for cervical manipulation for patients with cervical pain. Although patient had bilateral pattern of movement dysfunction and was not performing sedentary work for more than 5 hours per day, she did not feel worse when extending the neck and did not have a diagnosis of spondylosis without radiculopathy. As such, with 3/6 factors, patient approached, but fell short of the 4/6 required for 89% predictive value (i.e. likelihood of positive response to treatment). Relative to Cleland’s CPR for thoracic manipulation for cervical pain, the patient was positive only for decreased upper thoracic spine kyphosis and cervical extension range of motion greater than 30 degrees. This 2/6 finding, yields a predictive value of 71% and was similarly considered non-ideal for HVLAT.

Examination

After obtaining informed consent, the patient underwent a physical therapy examination. The NDI was administered followed by a subjective interview (including NRPS) and an objective physical exam. The physical examination process incorporated assessment of posture and structural alignment, cervical range of motion, and supine assessment of joint mobility. Upon initial evaluation, the patient’s baseline NDI was 38/50 or 76% disability (defined as “severe disability”). The NDI is a 10 question questionnaire with seven items related to activities of daily living, one related to pain, and one related to concentration (Wainner et al 2003). It has been shown to be a valid and reliable measure for patients with neck pain (Vernon and Mior 1991, Westaway et al 1998). Cleland et al (2006) found the minimum clinically important difference for the NDI to be 7/50 points, and a minimum change of 10/50 points to demonstrate a clinically meaningful change.

Subjective evaluation revealed no significant medical history beyond a diagnosis of anxiety. The patient reported having been treated for four visits in a physician-owned practice with “massage and stretches,” prior to requesting transfer to another clinic citing lack of progress and a “personality conflict” with the treating therapist. The NRPS was used to describe the patient’s current level of pain. Due to patient hyper-focus upon pain, the patient was not asked, as is typical and has been shown reliable in patients with low back pain, to describe best and worst levels of pain over 24 hours using the 11 point scale ranging from 0 (no pain) to 10 (worst imaginable), providing 3 numbers to be averaged by the therapist (Childs et al 2005, Pengel et al 2004). Patient reported 7/10 neck pain and headache at that time. Jensen et al (1994) suggest that 10- and 21-point scales provide sufficient levels of discrimination, in general, for chronic pain patients to describe pain intensity.

The postural exam revealed a decreased thoracic kyposis and forward head. Cervical active range of motion, tested in sitting, was 50 degrees flexion and 55 degrees extension using a single inclinometer. Cervical rotation was 45 degrees rotation bilaterally, tested both in sitting with a goniometer, and confirmed in supine with a single inclinometer. Many validity and reliability studies exist in the assessment of different measures for examining active range of motion. Youdas et al (1991) describe the reliability of seated active range of motion (AROM) measurements by either universal goniometry or with a cervical range of motion (CROM) device as having interclass correlation coefficients (ICCs) of 0.80 when measured by the same physical therapist. Rondinelli et al (1992) found the median range of error was 8.5° using the single inclinometer. The most recent and robust study to date, however, is a systematic review of 56 studies by Williams et al (2010) that describes “good” reliability and validity with both cervical range of motion devices (e.g. inclinometer), and goniometric measurement devices. Palpation assessment consisted of lateral glide testing in supine and revealed hypomobility of right C3/C4, left C5/C6, and right C7/T1 spinal motion segments. Fernandez-de-las-Penas (2005) found lateral glide testing of the lower cervical spine to be, “as good as radiological assessment for the diagnosis of intervertebral dysfunction.” Finally, cranio-cervical flexion test (CCFT) score was 18mmHg. Chiu (2005) described construct validity of the test in that subjects with neck pain were not able to generate the 28mmHg pressure of an asymptomatic individual, as patients with neck pain averaged 24mmHg. Intra-tester reliability of the test was found by James and Doe (2010) to be “excellent” with an ICC of 0.983.

Clinical Impression

The patient’s physical therapy diagnosis was neck pain and headache, and was classified as physical therapy practice pattern 4F (Impaired joint mobility, motor function, muscle performance, range of motion, and reflex integrity associated with spinal disorders) according to the American Physical Therapy Association’s Guide to Physical Therapist Practice (APTA, 2001).

Intervention

The patient’s episode of care consisted of 15 visits that can be divided into 4 general phases of intervention (see Table 3). Phase I consisted of an initial physical therapy evaluation, followed by 4 visits consisting of stretching, massage, and ultrasound (provided in a physician- owned physical therapy practice). Secondary to lack of progress, the patient was progressed to Phase II and referred for physical therapy to include spinal manipulative therapy, at a hospital-outpatient clinic. Phase II consisted of a second physical therapy evaluation, followed by 5 visits of physical therapy consisting of manual therapy including HVLAT and non-thrust manipulations. Phase III was initiated once the patient began to arrive for treatment without neck pain. The 2 visits in this phase integrated general exercise and cervical stabilization with HVLAT manipulation. Phase IV consisted of a single visit that included a cervico-thoracic HVLAT and more than a half-hour of soft tissue subscapular soft-tissue mobilization and massage.

Outcomes

Final discharge assessment occurred on visit 16 per patient request and report of feeling “almost as good as” pre-injury status. NDI score indicated minimally detectable change as well as clinically meaningful change from 76% disability (severe disability) to 18% disability (mild disability) was achieved (Vernon and Mior, 1991). Cranio-cervical flexion test abilities improved from 18mmHg to 28mmHg (the latter of which is considered within normal limits by Chiu, 2005). AROM cervical rotation improved from 45 degrees bilaterally to 85 degrees bilaterally, and neck pain had decreased from 7/10 to 0/10. Functionally, the patient re-acquired the ability to work an 8 hour shift of manual labor, to turn her head and back out of the driveway with her car, and to sleep through the night without waking in pain. The patient reported feeling 90% better over evaluation and 8 treatment visits in hospital-outpatient facility that included HVLAT in the plan of care versus 0% improvement over 5 visits in physician’s owned physical therapy practice (POPTS) that did not include HVLAT in the plan of care.

Table 3 – Interventions and Outcomes.

Key to Abbreviations: AA = atlanto-axial joint (i.e. C1/C2); AROM = active range of motion; B = bilateral; CCFT = cranio-cervical flexion test; Cx = Cervical; HVLAT = high-velocity low-amplitude thrust; IR = internal rotation; LR = left rotation; NDI = neck disability index; NRPS = numeric pain rating scale; mmHg = millimeters of mercury; OA = atlanto-occipital joint (i.e. C0/C1); P/A = posterior to anterior; PT = Physical Therapy; RR = right rotation; Rx = treatment; Sx = symptoms; Tx = Thoracic; UE = upper extremity

Phase Visit Interventions NRPS CervicalRotationAROM NDI CCFT
I 1-5 Initial evaluationStretchingMassageUltrasound
II 6 Second initial evaluationSeated grade IV right C3/C4 mobilizationSeated grade IV right C7/T1 mobilization 7/10 à 3/10 45RR45LR 38/5076% disability 18mmHg
7 Supine grade IV P/A lower cervical mobilizationSeated grade IV right C7/T1 mobilizationRight levator scap strain-counterstrainManual cervical traction 6/10 80RR75LR
8 Seated right gapping C7/T1 lateral thrust HVLATSupine T6/T7 “low dog” P/A HVLAT 5/10
9 Supine right C3/C4 lateral break HVLATSupine right OA cradle hold rotation HVLATSupine T4/T5 “low dog” P/A HVLATSeated left gapping C7/T1 lateral thrust HVLAT “Reduced neck pain” but 5/10 right unilateral headache 55B pre-Rxà80B post-Rx
10 Seated left gapping C7/T1 lateral thrust HVLATSupine rib one caudal thrust HVLATSupine AA rotary HVLATSupine T3/T4 “low-dog” P/A HVLATSuboccipital myofascial release 4/10 “flare-up.” Patient anxious that Sx will worsen if not immediately treated.
11 Treatment paused and patient referred back to physician secondary to left hand pain sustained during episode of syncope. Cranial nerve screening remained within normal limits and blood pressure was measured as 153/93. Patient was screened by physician for neurologic and/or cardiopulmonary pathology and was cleared to resume PT the following day. Patient complained only of left hand pain sustained during a drop attack and fall. 68RR68LR
III 12 Supine T11/T12 “low dog” P/A HVLATProne right rib one Osteopathic P/A HVLATSeated left gapping C7/T1 lateral thrust HVLATSupine right C3/C4 downslope HVLATSupine right OA rotational HVLATSupine T1/T2 “high dog” P/A HVLATSeated left C5/C6 cradle hold HVLAT 0/10 neck1/10 head 70B Pre-Rxà 80 LR, 80RR Post-Rx 16/5032% disability 28mmHg
13 Left prone rib three Osteopathic P/A HVLATSupine “low-dog” T11/T12 grade IV mobilizationsUpper body ergometerShoulder overhead press with cervical retractionChest press with cervical retraction 3/10Left upper rib and suprascapular pain
IV 14 Supine T1/T2 “high-dog” P/A HVLATSupine T4/T5 “low dog” P/A HVLATSupine C4/C5 cradle hold HVLATUpper body ergometerShoulder overhead press with cervical retractionChest press with cervical retractionTheraband pull-down in standing neutral spineCable-column pull-down in standing neutral spine 0/10 neck, but “stiffness” of upper thoracic and thoraco-lumbar areas
15 Prone right gapping C7/T1 lateral thrust HVLATProne with right UE in IR subscap soft tissue mob 1/10 acheCx/Tx junction
16 No treatmentDischarge assessment 0/10 neck 85LR85RR 9/5018% disability 28mmHg

The patient was asked to explain why she thought that she achieved better relief at one facility versus the other. The patient’s perception was that there was a difference in technical/manual therapy skill between the POPTS and hospital-based therapist, and that immediate trust and rapport, according to the patient, was created by “eliminating the headache” upon positioning for grade IV mobilizations during the first visit. The patient also offered that the hospital-based therapist took the time to treat her pain and “pain magnification secondary to my anxiety” where the POPTS physical therapist did not seem to be interested or have the time to do so. Specifically, she stated that the hospital-based physical therapist, “Listened, and took the time to try different techniques and positions to make me most comfortable . . . the other [POPTS] physical therapist didn’t listen . . when I tried to tell him that the home exercise program increased my headaches.” Finally, the patient reported that the POPTS therapist seemed “less confident in touching my neck. I think he was scared to hurt me. When you held my neck, it felt more confident, like you really knew what you were doing. That helped my anxiety, and you know how when I’m anxious and tense I hurt.”

Discussion

This study analyzed the outcomes of a patient with neck pain, determined to be a non-ideal candidate for HVLAT spinal manipulation, treated initially with transcutaneous electrical nerve stimulation (TENS), ultrasound, and soft tissue mobilization in a physician’s owned physical therapy practice; and later with high-velocity low-amplitude thrust manipulation, soft-tissue mobilization, and exercises, in a hospital outpatient physical therapy clinic. Consistent with the results of Cleland’s (2010) validation study, this case report is an example of a patient who responded well to HVLAT of the thoracic despite not meeting ideal criteria on Cleland’s(2007) CPR. In addition, the patient responded well to HVLAT of the cervical spine despite not meeting ideal criteria on Tseng’s (2006) CPR. It is noted that HVLAT was provided to the patient in one clinical environment, and no manual therapy beyond massage was provided in the other.

It has been suggested that the effects of HVLAT may not be limited to musculoskeletal biomechanical effects alone. Brennan et al (1991) noted increases in phagocyte and neutrophil cellular activity following HVLAT, suggesting a resultant increase in resistance and tissue healing activity. Following unilateral HVLAT of L5/S1, Karason and Drysdale (2003) described significant changes in blood perfusion (both ipsilaterally and contralaterally) in the corresponding dermatome. The pain relief that patients experience following HVLAT has been ascribed to a variety of mechanisms ranging from descending inhibition (Wright 1995, Skyba et al 2003) to the increased blood endorphin levels noted following HVLAT (Vernon et al 1986). Similarly, increases in pain pressure thresholds have been realized in remote dermatomes (Fernandez-de-las-Penas et al 2007), muscle trigger points (Oliveira-Campelo et al 2010) associated with specific cervical HVLATs. Finally, decreases in muscle inhibition of distal muscles have been described following HVLAT spinal (Suter and McMorland 2002, DeVocht et al 2005) and sacroiliac joints (Suter et al 2000). Given the patient’s stated pre-treatment anxieties it can be theorized that the therapeutic effect of HVLAT in this patient may have been, at least in part, non-biomechanical relaxation (parasympathetic bias) and pain relief that ultimately lead to improved reception of therapeutic intervention. Future research will be required to further illuminate the non-biomechanical effects of HVLAT, particularly in patients with lower positive predictive values as defined by clinical prediction rules.

Alternatively the patient described greater trust in her second therapist on the basis of the confidence that the therapist projected, the therapist taking the time to listen in great depth and detail to her complaints and the immediate elimination of headache upon first visit. Evidence suggests that patients who do not receive HVLAT as part of their physical therapy care may be at increased risk for worsening disability(Childs et al 2006) and that therapy that includes HVLAT has a “better effect than massage for cervicogenic headache” (Bronfort et al 2001). In addition, while it is known that rapport is a vital part of the therapeutic process, helping to explain and predict outcomes in patients with addiction(Joe et al 2001, Joe et al 2009) little is known, about the relative impact of the non-clinical factors (trust, therapist communication skills, patient perception of therapist confidence, patient perception of therapist skill) upon clinical outcomes, particularly with respect to those patients who cannot be classified as ideal candidates for HVLAT on the basis of CPR’s.

If non-clinical factors are found to be of value in outcome prediction in patients who are not found to be ideal candidates for HVLAT on the basis of existing CPR’s, it is worth considering that some of these factors may require additional (sometimes non-billable) time to establish. Simply taking a few minutes of extra time to listen to a patient’s complaints that may not be directly applicable to the physical therapy case may have the effect of easing a patient’s anxieties and allow for improved outcomes as a direct effect of relaxation, or by relaxing the patient sufficiently to optimally benefit from manual modalities. As such, the treatment environment and/or direct 1:1 time spent with the patient may be an important factor in predicting outcome in patients such as the one described in this case report. Physical therapists in non-physician-owned environments have been found to spend as much as 60% more time per visit with their patients (Mitchell and Scott, 1992). The patient in this case was treated initially in a physician’s owned practice where she did not improve, and subsequently in a non-physician owned practice (where greater direct 1:1 time was spent with the patient), where she did improve. In other words, additional research is needed to determine if it is time spent building rapport with the patient who scores poorly on the CPR’s, or the treatment environment itself, that ultimately proves more predictive. Additional research will be required to fully explore the impact of non-clinical factors in predicting outcomes in patients who score in the less-than-ideal range on established clinical prediction rules. Early identification of these patients, and the factors (both clinical and non-clinical) that predict their outcomes from the receipt of specific physical therapy techniques and treatment environments may lead to improved efficiency and cost-effectiveness in the treatment of this subgroup of patients with neck-pain.

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