Introduction:

Mechanical diagnosis and therapy (MDT) of the cervical spine, also known as the McKenzie method, has been the focus of research in the field of musculoskeletal physical therapy in recent years. The MDT focuses on the patient’s symptomatic and mechanical responses to the systematic application of repetitive end-range movements. Adherent nerve root (ANR) is a specific form of dysfunction that occurs secondary to trauma, commonly after the resolution of a discogenic problem or derangement, resulting in referred pain. According to May, out of 607 spinal patients with mechanical syndrome classifications, only 3% were classified as a dysfunction, while only 1% were classified as adherent nerve root (ANR). Pain due to ANR is produced at a limited end range, which does not change rapidly, and abates once the end-range position is released.

The criteria for ANR classification are (McKenzie and May, 2003 a,b – 2006):

• history of cervical radiculopathy or surgery in the past that has improved, but is now unchanging,

• symptoms are intermittent,

• symptoms in the arm and/or forearm, may include ‘tightness’,

• upper limb tension tests (ULTT) clearly restricted and consistently produces concordant pain or tightness at the end range,

• there is no rapid reduction or abolition of symptoms and no lasting production of distal symptoms.

Experimental studies by Key and Ford, 1948 have demonstrated that after a disc injury or prolapse, there can be adherences between the disc and nerve root. In a review by O’Connell (1951) the common finding of adhesions between the posterior longitudinal ligament and the nerve root found during discectomy is a consequence of tissue healing and is sometimes the only obvious cause of symptoms. No previous case reports have described McKenzie’s assessment and management of patients classified as having a cervical ANR. So, the purpose of this case review is to describe the application of MDT for an adherent cervical nerve root in a medical student.

Case history and physical examination:

A male, 22 years old, reported five months left intermittent cervical pain, along with radiation (pulling sensation and tingling) on the medial side of his arm and forearm. The patient suffered from intermittent left-side neck pain in the past, but he neglected to treat it. The patient was examined using the McKenzie method. The numerical analogue scale (NAS) was 5/10 and the patient completed initial pain drawings using different colours to depict different symptoms.

Aggravating factors were sitting, side bending toward the right side, and after a long period of walking. Easing factors were supported arm position across the chest. Neurological bedside examination (Bender C, et al 2022) revealed no neurological deficits (dermatomal, myotomal, reflexes). Range of motion assessment revealed a moderate loss in side bending to the right, and retraction. The upper limb tension test (ULTT) performed actively and passively reproduced the patient’s familiar pain with ULTT1,2a for the median nerve and ULTT3 for the ulnar nerve. The patient had a slouched sitting posture and upon correction, into an erect posture, cervical pain subsided immediately only to return once the patient was allowed to slouch again. During the structured McKenzie testing, it was not possible to identify a position or movement that centralized or peripheralized symptoms. A provisional classification with cervical ANR dysfunction along with movement coordination deficit was documented for/on the day of assessment. On follow-up assessments, the symptoms and physical findings were consistent with the initial day assessment. The patient’s history and physical examination fit into the criteria for an ANR and a derangement was ruled out by failure to centralize as well as lack of response to provocative testing strategies.

Treatment:

A treatment strategy was planned to provide a regular remodeling program that will eventually alter the adhesions that limit mobility. During the process of remodeling, some arm pain and tightness or discomfort could be felt, but any discomfort reproduced may subside within a few minutes. It should be noted that nerve root adherence is the only clinical situation in which the deliberate provocation of distal symptoms may be permitted as tolerated during the application of manual therapy techniques. The techniques for treating cervical ANR consisted of cervical flexion, flexion with side bending to the right, extension procedures along with upper limb neurodynamics, strengthening of deep neck stabilizers and para scapular muscles, postural correction, and a home exercise program. The treatment for cervical ANR also required the patient to perform exercises that produced concordant arm and forearm symptoms temporarily to ensure that exercises affected the involved tissue (McKenzie and May, 2006).

Discussion:

This case reported the McKenzie classification and management of a patient with a 5 months history of neck pain and radiation, and functional disabilities. The physical examination led to the conclusion that symptoms were caused by nerve root adhesions. The cervical ANR is a symptom-based diagnosis and its validity has not been compared against a reference standard. However, such a diagnostic classification through the principles of MDT provided a pathway to successfully treat an individual with chronic neck pain.

Furthermore, the repeated movement testing and treatment in this case study were performed by a clinician without specialized training and certification in MDT. A study by Deutscher et al, 2014 demonstrated that when implementing the principles of MDT for the treatment of low back pain, fewer therapy sessions were required when treatment was performed by a clinician with a McKenzie education level of part C or greater. This indicates that clinicians who have not undergone additional training in MDT can successfully implement the fundamental principles of MDT, although it is possible that the plan of care may be longer.

References:

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