Neurology Consultation

May 24, 2004

David Hinman

Age: 34

Occupation: Call center worker, US Off-track Betting

Referral: Susan Strom, DC

Diagnoses:

1. Probable entrapment of L ilioinguinal/obturator nerves with a post-traumatic neuroma (herniorrhaphy Feb/ 1998).

2. Bilateral L1 sensory losses; in association with additional odd regional sensory losses (including S4, S5) in addition to non-radiating low back pain: etiology unclear.

3. Aspects of a now-chronic central de-afferentiation neuropathic pain syndrome.

At the request of Dr. Strom, a neurological review is sought for this single, thirty-four-year-old businessman and former soccer player for a complex of pain & paresthesia of the left groin & thigh area initially connected with a diagnosis of a L inguinal hernia in 1998, presumably arising in response to vigorous weight training routines. For purposes of analysis, I have arbitrarily divided this 6-year period into Phase I, II, III, and IV.


Phase I

Mr. Hinman reports that he was healthy as a horse prior to the development of a left groin bulge and pain in early 1998, in a period when he was working out with a weight machine at the West Side Athletic Club in Portland. A diagnosis of a L inguinal hernia was followed by surgical repair by a Dr. Jutton in February of that year.


Phase II

In the immediate post-surgical, while intermittent, sharp L groin pains slowly faded, he was left with two new symptoms, viz. (i) a sudden, unheralded pain in the area of the left inguinal surgical scar, accompanied by (ii) urinary urgency with delay in voiding, which also faded, but left an unpleasant residual noted as the months passed: if his pelvic muscles were strained with any activity the (i) and (ii) symptoms noted above returned.

Other symptoms relatively late in Phase II (April-May 1998) he found that "I became increasingly sensitive to sugar. I would get drowsy, sluggish, and nauseated after any dessert."


Phase III [1999-Present]

Mr. Hinman then went on to lay out a host of symptoms and difficulties after that year, persisting to one degree or another down to the present, involving the left inguinim and surrounding tissues (see mapping), which have different functional consequences in his life:

  1. "I can't run without pain. At first the pain was limited to the hernia site, but over time has extended to both knees and calves." (R > L)
  2. "Both legs seem tighter, they are not so flexible."
  3. Occasional pain in the L groin, starts there and then spreads in to L buttocks, arising in various activities, including running.
  4. As a result of this discomfort, "My gait has changed" (illustrating) with a longer strode length and widening of the base.
  5. Emergence of chronic low back pain and pressure without radiation into either thigh, muscle cramps since the summer of 2003.
  6. Post-surgical development of hemorrhoids; ? with some perianal sensory loss. Some question of awareness of passage of stool during defecation; reports no bowel urgency or stool incontinence.
  7. NB: After a muscle strain in March, 2004, mini-version of left inguinal symptom flare in addition to pain on ejaculation ; sought urological care (Dr. McEvoy) as he also noted loss of sensation on the glans. He took an anti-biotic (Levaquin) for the urological problems for four months, which seem to have resolved.


Past Medical History

General excellent health up until 1998. He reports a motor vehicle collision at age 17 with loss of consciousness (LOC 30-60 seconds) and a nasal fracture, the latter surgically repaired, but, he reports, no other apparent sequella. Thereafter described being involved in "4 or 5" minor MVCs, none of which led to ER admission or left him with residual difficulties, e.g. no tinnitus, hearing loss, vertigo, etc.


Personal & Social

Mr. Hinman reports that he grew up in Columbia, MD, obtained an MBA degree in business administration at the University of Oregon, and has lived in Oregon for 10 years; he is unmarried. He played recreational soccer for many years prior to 1998.


Examination

Standing 5' 8" and weighing 185 lbs., Mr. Hinman was a sturdily built, well-groomed, R-handed man wearing glasses and walking without support, ataxia, or limp, but perhaps a slightly widened gait.

He was alert, open, and oriented, and spoke without a suggestion of stutter, lisp, dysarthria, or loss of prosody. There was no suggestion of loss of grasp, aphasia, or irrelevancy of discourse.

By inspection, his facies are symmetic, and the tongue midline, sense of smell was not tested.

Extraocular movements (EOMs) were conjugate without a fixed or positional nystagmus; there was no squint, and his pupils were equal and reactive to light & accommodation. There were not tics, tremors, or myoclonic jerks of the head or neck. Visual acuity, funduscopic exam, and visual fields (by confrontation) were not tested.

Hearing was bilaterally intact for both low & high-pitched sounds. However, the Weber test lateralized slightly to the left ear. OKN-drum testing was not aversive.

Sensory testing to pin, brush, position, and vibratory sensation in the fingers revealed sensory loses in the left hand to pin and brush testing (see mapping) with relative sparing of vibration & position sensibility. Sensory testing of the fingers of the right hand were normal to pin, brush, position, and vibratory sensation; similarly, there were no sensory losses in the toes of either foot.

Sensory mapping of the left groin and thigh both legs revealed (see mapping):

  1. Bilateral ilioinguinal nerve loss
  2. Loss of sensation along the inner aspect of the L thigh in obturator nerve territory
  3. Generalized loss of sensation in the left L1 dermatome
  4. A probable deep structure surgical scar neuroma of the old inguinal herniorrhaphy site (probable origin of movement associated post-op paresthesia and diffuse regional pain in the peripheral neural
  5. Perianal (S4, 5) sensory lost; note: intact cremasteric reflex, anal wink reflex not tested


Cerebellar testing of finger-to-nose was quick and accurate, and past-pointing was also normal. The range, rate and rhythm of alternating movements were symmetrical & physiological; there was not resting or kinetic tremor of the upper limbs.


Reflex examination:

 

Right

Left

Jaw Jerk (V)

Absent

Biceps (C6)

Trace

Trace

Triceps (C7)

Trace

trace

Abdominal

Absent

Absent

Quadriceps (L4)

2+

1+ /2+

Achilles (S1)

2+

2+

Plantar

Flexor

Equivocal

Clonus

Absent

Absent


Mr. Hinman could stand in a routine Romberg position with his eyes open & closed without losing his balance. However in a heel-toe stance (modified Romberg), he could stand with his eyes open, but when closed there was much teetering and surprise at the task’s difficulty, similarly when trying to tandem walk with his eyes closed.


He could stand on his heels & toes and could prove an athletic hop on either foot; there is no case for gross weakness or loss of control of the lower extremities.


Discussion

For this veteran of examining rooms, and multiple physician reviews, I suspect that (i) a post-surgical neuroma in the region of the inguinal canal that was surgerized (herniorrhaphy), behind much of the localized pain & paresthesia described with activity, to which has been added over time (ii) additional neurological losses from some other quarter to damage the R ilioinguinal nerve, the L1 nerve root, and to invoke chronic low back pain. The etiology remains undefined.

I suspect that the equivocal left plantar response can be viewed as a vintage left over from his concussion at age 17. As he has been an athlete, I presume that the surprising difficulty he had with tandem walk and the modified Romberg position with his eyes open, represents a long-standing compensatory response of visual system to some concomitant vestibular damage with his concussion episode.


Recommendations:

  1. For his bilateral L losses, an MRI of the lumbar spine is now in order if not already done.
  2. Whether to try and perform a Caine block of the left inguinum, and if successful in eradicating his pain and paresthesia vs. surgical exploration with a microscopic review to find a neuroma—which could be as large as a pinhead—I leave for a wider discussion with pain physicians and surgeons who do hernia repairs.


I deeply thank Dr. Strom for asking me to look into this man’s chronic post-operative difficulties. I shall be happy to pursue these various matters raised if requested.


Robert J. Grimm, MD, FACD


Cc: David Hinman

Dr. Strom

Dr. McEvoy