Physical Therapy Chosen Over Lumbar Microdiscectomy

A Functional Movement Systems Approach

Kyle A. Matsel, Kyle Kiesel, Gray Cook, Mark A. Jones

Subjective Examination

Chuck is a 28-year-old male who presented to the clinic with a diagnosis of low back pain. Chuck reported that he injured his low back in a rear-end motor vehicle accident (MVA) 8 weeks prior. As a result of the MVA, Chuck began having significant low back pain with left lower extremity symptoms that he reported extended from his low back centrally to the sacral region, left buttock and left posterior leg, including the full dorsal and plantar surfaces of his foot and toes (Fig. 29.1). He presented with no major red flags such as numbness, pins and needles, cauda equina or spinal cord–associated symptoms, and no symptoms in the right leg or upper body.

Fig. 29.1 Body chart illustrating area of Chuck’s symptoms.

Immediately post-accident, Chuck was taken to the local hospital, where initial emergency room radiographs were negative for fractures, and he was referred to a neurosurgeon for consultation. Magnetic resonance imagining (MRI) revealed a two-level lumbar disc herniation at L4/L5 and L5/S1. Chuck was given the option at that time to attempt physical therapy or proceed with surgical intervention to address the herniated discs that were considered to be the cause of his pain and associated work-activity limitations.

Chuck is a mechanic by profession and is on his feet on concrete most of the day. No modified duty or work restrictions were suggested by the referring physician. As a mechanic, Chuck was required to lift parts, squat down to work on cars and stand for prolonged periods of time. Chuck was not currently engaged in a fitness program; however, he had previously participated in weight lifting for exercise and wished to return to this in the future. Given the nature of his work, Chuck decided to attempt physical therapy before resorting to a lumbar microdiscectomy operation. Screening questions for potential psychosocial issues (i.e. yellow flags) regarding Chuck’s understanding of his problem, his beliefs regarding management, stressors in his life and his level of coping all suggested these were not a problem in his case.

At the initial examination Chuck reported a current pain rating via the visual analogue scale (VAS) of 5/10; however, he stated that the pain could reach 8/10 at its worst by the end of the workday. He reported no significant past medical history and no previous orthopaedic surgeries. Chuck’s pain increased with prolonged standing and walking and appeared to decrease with sitting and stretching of his low back by bending forward. Other spinal movements (e.g. twisting) and lower limb movements (e.g. hip, knee) were not a problem. He reported no significant difficulties with sleeping through the night and noted his preferred sleeping position was side-lying with his knees pulled up toward his chest.

Reasoning Question:

1. What were your hypotheses at this stage regarding dominant ‘pain type’ (nociceptive, peripheral neuropathic, nociplastic)?

Answer to Reasoning Question:

At this point, it appeared that Chuck’s presentation was consistent with a nociceptive-dominant pattern based on the mechanical nature of the symptoms and apparent lack of yellow flags. Symptoms were relatively localized to the lumbar spine and left posterior lower extremity, with no widespread areas of symptoms or inconsistent patterns of provocation that are typically associated with nociplastic pain (e.g. Smart et al., 2012a, 2012c). On the other hand, the area of posterior leg pain and confirmed multi-level disc herniation was potentially consistent with a peripheral neuropathic type of pain problem (e.g. Smart et al., 2012b; Treede et al., 2008), and as such, a neurological examination would be important to help in differentiation. However, the inclusion of the full plantar surface of the foot and toes in his pain pattern is atypical for compromise of a single nerve root and may instead reflect a peripheral nerve compromise.

Reasoning Question:

2. At this stage, did you have any hypotheses regarding potential ‘sources of symptoms’ (nociception) and ‘pathology’ for Chuck’s symptoms, and were there any ‘precautions to the physical examination and treatment’ identified from the clinical picture thus far?

Answer to Reasoning Question:

With a multi-level disc herniation confirmed by MRI and radiating symptoms down the lower extremity, we might expect Chuck would have reported some relief from lumbopelvic extension postures or movements. In contrast, Chuck reported movements and postures involving flexion as pain relieving. Because this is not the typical presentation for a pain-provoking discogenic lesion, it is reasonable to hypothesize that the herniations may have been asymptomatic. Any structure, somatic or neural, within the area of symptoms could have been a source of nociception. However, given that Chuck’s provocation of symptoms was associated with lumbopelvic extension-oriented posture and movement (e.g. standing and walking) and that his symptoms were eased with flexion activities (e.g. sitting and bending forward), plus neither hip or knee movements were affected, it is also reasonable to hypothesize that the source(s) of nociception was located within the lower lumbar spine and/or sacroiliac joint. The lack of overt neurological symptoms (e.g. numbness, pins and needles, weakness) suggested that frank nerve root compression was unlikely, although a neurological examination would be required to test this further, and thus compromise of a nerve root and/or peripheral nerve remained a possibility.

Although potential sources of nociception will be tested further in the physical examination, operating under the assumption that the herniated discs were not the pain generators and that no other overt pathology was evident, the focus of reasoning shifted to movement-pattern dysfunction maintaining nociception. That is, the MVA was likely responsible for initial nociception from the lumbar spine and possibly neural tissues. In response to the pain, the CNS will alter the motor control (timing) of the inner core muscles (Hodges et al., 2013). If the inner core muscles (multifidus, transversus abdominis, pelvic floor, diaphragm) are delayed in their activation, a more global response of the larger force-producing muscles will occur. This is called a ‘high-threshold strategy’ (Cholewicki et al., 2002) and involves a global co-contraction of erector spinae, rectus abdominis and the external obliques, which is thought to protect the painful region from further injury. A high-threshold strategy is ideal for situations where the system is under high load; however, it is not necessary under less stressful situations. The increased compressive forces that occur through the spine due to the co-contraction of the erector spinae and rectus abdominis muscles may be generating and maintaining nociception and, therefore, Chuck’s symptoms. The physical examination will also be used to identify any dysfunctions in movement and control and, if present, what specifically is the cause of any dysfunction.

With respect to precautions that should be taken, although it appears that the herniated discs may be chronic and asymptomatic in nature, exercises that are known to increase disc pressure and potentially cause irritation of the disc or adjacent structures will need to be avoided. For example, loaded lumbar flexion with rotation exercises that may stress the disc will not be a part of the treatment plan, especially if an increase in peripheralization of symptoms in the lower extremity occurs.

Clinical Reasoning Commentary:

Musculoskeletal clinicians need to be able to reason on multiple levels and across multiple categories of decisions (i.e. hypothesis categories). With a hypothesis regarding ‘Pain type’ as nociceptive dominant and/or neuropathic based on the clinical pattern of symptom area, behaviour and history, combined with equivalent negative findings for nociplastic pain, reasoning regarding ‘sources of symptoms’ (nociception) and ‘pathology’ is appropriate. A case is made against a discogenic ‘source’ despite the radiological evidence of pathology. The possibility of neuropathic and other tissue sources is kept open with plans for further testing in the physical examination, and the clinical reasoning has expanded to include potential ‘contributing factors’ in the form of ‘movement pattern dysfunction’ maintaining Chuck’s symptoms and disability. The clinical reasoning throughout this portion of the answer reflects the balanced reasoning that musculoskeletal clinicians are required to undertake between ‘sources of symptoms’, ‘pathology’ and ‘impairments’, as discussed in Chapter 1.

On yet another level of reasoning, ‘precautions to physical examination and treatment’ are identified with respect to both pathology (i.e. disc herniation) and symptom behaviour (i.e. peripheralization).

Physical Examination

Posture

• Mild increased lumbar lordosis

Neurological Examination

• Normal sensation to light touch
• Normal strength through all myotomes
• Normal reflexes at the patellar tendon (L3) and Achilles tendon (S1) levels.

Selective Functional Movement Assessment (SFMA)

Assessment findings are reported according to the SFMA categorizations of ‘functional and non-painful’, ‘functional and painful’, ‘dysfunctional and non-painful’ and ‘dysfunctional and painful’, with clarification of the dysfunction in parentheses and SFMA categorization of dysfunction highlighted in italics (App. 29.1; Cook, 2010):

• Cervical flexion = functional and non-painful
• Cervical extension = functional and non-painful
• Cervical rotation = functional and non-painful bilaterally
• Upper extremity pattern 1 = functional and non-painful bilaterally
• Upper extremity pattern 2 = functional and non-painful bilaterally
• Multisegmental flexion = dysfunctional (restricted range of movement [ROM]) and non-painful
• Multisegmental extension = dysfunctional (restricted ROM) and painful (lumbar spine)
• Multisegmental rotation = dysfunctional (restricted ROM) and non-painful bilaterally
• Single leg stance = dysfunctional (loss of lumbar-pelvic starting position and excessive exertion in maintaining single leg stance) and non-painful bilaterally
• Overhead deep squat = dysfunctional (loss of upper extremity flexion and inability of the hips to break parallel) and non-painful
• SFMA scoring (App. 29.2) = 56% total dysfunction.

App. 29.2 Selective Functional Movement Assessment (SFM) scoring illustrating the categorical and checklist score sheets for the seven top-tier movements of the SFMA. Scoring: there are 50 total possible checks on the list. Every dysfunction gets one check. The total number of checks is added up and divided by 50 and multiplied by 100 to get a percentage of total dysfunction. Key: DN = dysfunctional and non-painful DP = dysfunctional and painful FN = functional and non-painful FP = functional and painful LRF = lateral rotation flexion MRE = medial rotation extension (Reproduced with kind permission from Functional Movement Systems.)

Multisegmental flexion ‘breakout’ (App. 29.3) (Cook, 2010):

App. 29.3 Multisegmental flexion ‘breakout’ flowchart illustrating the systematic reduction of a global movement pattern into its regional components. Key: DN = dysfunctional and non-painful DP = dysfunctional and painful FN = functional and non-painful FP = functional and painful JMD = joint mobility dysfunction SLR = straight leg raise SMCD = stability motor-control dysfunction supine knee to chest (T) = supine knees to chest holding thighs TED = tissue extensibility dysfunction (Reproduced with kind permission from Functional Movement Systems.)

• Standing unilateral (weight-bearing on right side) forward bend = dysfunctional (unable to touch toes) and non-painful bilaterally
• Long sitting toe touch = dysfunctional (unable to touch toes) and non-painful
• Active straight leg raise test = dysfunctional (restricted mobility – 35 degrees) and non-painful bilaterally
• Passive straight leg raise test = dysfunctional (restricted mobility – 40 degrees) and non-painful bilaterally with no reproduction of leg pain = ‘bilateral posterior chain tissue extensibility dysfunction’ (Cook, 2010)
• Supine knees to chest holding thighs test – functional (full hip flexion joint mobility) and non-painful
• Prone rock (‘child’s pose’) lumbar spine flexion test = dysfunctional (limited joint movement with non-uniform spinal curve) and non-painful = ‘lumbar flexion mobility dysfunction’

Local biomechanical assessment of lumbar spine:

• Tender to palpation over lumbar multifidus muscles at L4/L5 level bilaterally
• Tender to palpation over lumbar erector spinae muscles left > right bilaterally
• Central posterior to anterior glides of the lumbar vertebrae indicated no hypomobile segments (i.e. no evidence of ‘lumbar flexion joint mobility dysfunction’).