MSK MIMICS SWEDISH NEUROLOGY UPDATE 170922 Erik Ensrud, MD PM&R/EMG/Neurology/Neuromuscular Medicine Associate Professor Oregon Health Sciences University 1 MIMICS? Henry Walter Bates English, ~1858 Brazil ? normal imitates noxious German, ~1880 Lived in Brazil noxious+noxious 2 Neuromuscular Mimic-definition A musculoskeletal condition that presents with pain or discomfort suggestive of a neuropathic or myopathic etiology. 3 Reasons to care about Neuromuscular Mimics Common causes of limb pain Frequent reason for clinic/EMG referral ”Pain in limb-? radiculopathy, ? CTS” Treatable conditions Neuro residency training programs (aka Neuro-ICU beatdowns) do not cover as not part of board exams. PM&R programs (aka Inpt Rehab beatdowns) usually have some coverage, although this can be quite variable. 4 THE BOOK OF PRESTON FIRST CHAPTER Verses 7 and 8 “In practice, EDX studies serve as an extension of the clinical examination and should always be considered as such. Accordingly, a directed physical examination should always be performed before EDX studies in order to establish a clinical diagnosis and establish a differential diagnosis.” 5 Blind men and an Elephant? Originated in the Indian subcontinent from where it has widely diffused into Jain, Buddhist, Sufi, and Hindu lore. It has been used to illustrate a range of truths and fallacies; broadly, the parable implies that one's subjective experience can be true, but that such experience is inherently limited by its failure to account for other truths or a totality of truth. AKA alt-truth or alternative facts? 6 Antibody? Wet garbage HR +/-? bag? Late Positive response? sharp wave? NMJ? Ethical? Motor neuron? Hanabusa Itcho 7 Are these really conditions I am going to see? Need to look for and recognize to identify-they are very common i.e. one week in EMG lab-of 60 EMGs scheduled, 9 patients had neuromuscular mimics- identifying these mimics improved the diagnostic rate by over 15% 8 Musculoskeletal Exam Tests: Advantages FAST/EASY/EFFECTIVE Ability to diagnose quickly at bedside or exam room with appropriate physical exam Timesavers for the Provider (It’s All About You!)-keep up your clinic flow Fewer unnecessary MRIs ordered with time- consuming follow-up 9 Musculoskeletal Exam Tests: Pearls Check bilateral limbs for side-to-side comparison: non-involved side first when possible Ask, “Is that the same pain you have been experiencing?” * Patients can have more than one condition- i.e. CTS and DeQuervain’s 10 Musculoskeletal Exam Tests Pearls: Wince sign Look for the “Wince” sign for positive test • Eye blink/face grimace • Not just mild discomfort 11 Five Top Mimics Upper Extremity Supraspinatus/rotator cuff tendonitis* Biceps tendonitis Lateral epicondylitis De Quervain’s tendonitis CMC joint arthritis 12 Supraspinatus/Rotator Cuff Tendonitis 13 Supraspinatus tendonitis mimics Upper to mid-cervical radiculopathy* 14 Supraspinatus tendonitis Symptoms/risk factors Pain with arm movement, esp. overhead *Difficulty sleeping when lying on affected side Pain may radiate up towards neck and down arm, even beyond elbow Repetitive movements-esp. overhead, acromion anatomy (hooked) Especially in people with underlying neurologic disease, due to periscapular muscle imbalance leading to instability of glenohumeral joint 15 Supraspinatus Tendonitis: Hawkins Shoulder Test most sensitive at 92% Humerus flexed 90 deg Elbow flexed 90 deg Examiner’s hand stabilizes pt’s shoulder Examiner pulls down on pt’s forearm WITH RAPID JERK to internally rotate humerus Head of humerus pinches tendon under acromion PAIN when inflamed 16 Supraspinatus tendonitis-Treatment NSAIDs PT-stretching, strengthening posterior muscles Steroid injection Confirm with MRI or US- need soft tissue visualization PT/PM&R/Rheum/Orthope dic referral 17 Biceps tendonitis-long head 18 Biceps tendonitis mimics Upper cervical radiculopathy* 19 Biceps tendonitis symptoms/risk factors Achy, poorly localized shoulder and upper arm pain Pain with lifting, esp. flexion and overhead Repetitive arm movements-esp. overhead Shoulder arthritis Age Rapid increase in exercise 20 Yergason test for biceps tendonitis 21 Biceps tendonitis treatment Ice-tid over area until numb (superficial) NSAIDs Avoid overuse Steroid injection-caution to avoid injecting tendon PT 22 Frozen paper cup for ice therapy 23 Lateral epicondylitis 24 Lateral epicondylitis mimics Ulnar neuropathy*-pain around elbow Lower cervical radiculopathy-pain can radiate distally along forearm/ulna 25 Lateral epicondylitis symptoms/risk factors Elbow pain, esp. lateral elbow pain Exacerbated by arm use, esp. wrist extension Overuse of wrist extension/supination-any activity but tennis is esp. common 26 Lateral epicondylitis-exam test • Palpate 0.5-1cm distal to the epicondyle (max . tenderness to palpation) 27 Lateral epicondylitis treatment Ice-tid over area until numb Stretches NSAIDs Tennis elbow strap Steroid injection 28 Lateral epicondylitis Wrist extensor stretch 29 Lateral epicondylitis Elbow strap Serves as partial proximal fixation 30 DeQuervain tendonitis 31 DeQuervain tendonitis mimics Carpal tunnel syndrome “wrist pain”* C6 radiculopathy-pain along distal radius Superficial radial sensory neuropathy 32 De Quervain’s tendonitis symptoms/risk factors Pain with weight-bearing wrist extension, wrist turning, grasp Numbness(real!)-due to irritation of the superficial radial sensory nerve Pain with grasping/pinching Chronic overuse (aka “nursemaids”), arthritis, direct trauma 33 De Quervain’s tendonitis Finklestein’s test Have pt wrap fingers around thumb, “as if it were an egg” (If they grasp too tightly they may splint the wrist and decrease test ROM, reducing sensitivity) Ulnar deviate the wrist 34 De Quervain’s tendonitis- treatment Ice-tid until numb NSAIDS Splint immobilization, avoiding repetitive movements Hand therapy-iontopheresis Steroid injection-avoid tendon 35 Carpometacarpal joint arthritis 36 CMC arthritis mimics Carpal tunnel syndrome* Lower cervical radiculopathy 37 CMC arthritis Symptoms/risk factors Pain at the base of the thumb *Weakness of pinch/grasp, may give-way on APB testing Women, esp. post-menopausal As much as 1/3 of women > 40yo have CMC changes on x-ray…may be secondary to hypermobile joints Arthritis, including OA, RA, and gout 38 CMC arthritis Exam test • Compression of the CMC joint by grasping metacarpal and applying pressure to compress the CMC joint CMC • Movement like a mortar and pestle or Atari joystick 39 CMC arthritis treatment NSAIDs Thumb splint for stabilization Steroid injection Joint replacement 40 BEING HAPPY MADE LUDICROUSLY SIMPLE 41 4 Top Mimics Lower Extremity Hip joint osteoarthritis Greater trochanteric bursitis Pes anserine bursitis Plantar fasciitis 42 Hip osteoarthritis 43 Hip OA mimics Upper lumbar radiculopathy* Sciatica Knee DJD* 44 Hip OA symptoms/risk factors Pain in anterior hip/groin/buttock/”back” which can radiate down thigh Worse with weight bearing and activity Age (>65yo x-ray changes in 5%), increased BMI, hx weight-bearing sports including running, standing/lifting work, genetics- Icelandic deCODE work on collagen genes 45 Hip bedside exam-supine or seated Ext rotation:*Internal rotation External Rotation Internal Rotation Pain free/min pain Elicits hip joint pain if OA changes present 46 Cheech and Chong 47 Hip OA test-X-ray: when joint OA present, internal rotation compresses joint causing **periosteum to periosteum contact PAIN 48 Hip OA treatment Acetaminophen before NSAIDs due to likely long-term use (both effective in trials) PT helpful, esp. with gait Cane-use contralateral to OA hip Orthopedic surgery consultation 49 Greater trochanteric bursitis 50 Trochanteric bursitis mimics Upper lumbar radiculopathy* Sciatica if bilateral-neuropathy 51 52 Trochanteric bursitis symptoms/risk factors Thigh pain, esp. lateral. buttock pain Radiates to the knee-some pts report to the calf Can be worse with sleeping on affected side, walking (esp. up stairs) Risks-hip trauma, hip OA, elderly, obesity 53 Trochanteric bursitis lying exam test 54 Trochanteric bursitis seated exam test *Patient seated, facing examiner *Examiner palpates along both lateral femurs until reach greater trochanters *Side-to-side differences? *Wince sign? 55 Trochanteric bursitis treatment Injection-steroid/lidocaine VERY EFFECTIVE Pain may worsen 1-2 days before improving-ice to area (flexible frozen gel or frozen peas against lateral hip) Stretches 56 Trochanteric bursitis treatment Stretches-best after injection 57 Pes anserine bursitis 58 Pes anserine bursitis mimics Lumbar radiculopathy, esp. L4* 59 Pes anserine bursitis symptoms/risk factors Leg pain Medial knee pain-esp. when ascending stairs/climbing Athletes-esp. in sports with side-to-side cutting activity such as tennis, soccer 60 Pes anserine bursitis-physical test is tenderness to palpation at bursae 61 Pes anserine bursitis- treatment Rest Ice-tid until numb NSAIDs PT Steroid injection Rarely surgery-athletes 62 Plantar fasciitis 63 Plantar fasciitis mimics Distal sensory neuropathy* Small-fiber neuropathy (burning sensations) L5/S1 radiculopathy-unilateral distal leg pain 64 Plantar fasciitis symptoms/risk factors Foot pain-burning and gnawing in character Worse when standing/weightbearing, esp. in morning when get out of bed *In contrast with small-fiber neuropathy which is worse at night when off feet Tight Achilles tendon (shortens plantar fascia), obesity are risk factors 65 Medial calcaneus palpation Test Palpate at the anterior-medial calcaneus (site of PF insertion)