Carpal Tunnel Syndrome 2018 Anthony Chiodo, MD, MBA Michigan Medicine Department of Physical Medicine and Rehabilitation Definition

 Clinical Syndrome  Numbness, Tingling, Burning and Pain  Median nerve distribution of the hand  Localized compression of the median nerve at the wrist  Local ischemia and mechanical damage  Sensory nerves more susceptible  Comparative latencies used to make the diagnosis  Sensitivity 85%, specificity 82-85% Utility of Symptoms in Predicting Disorder: Hand Diagram Calfee FP. Performance of Simplified Scoring Systems for Hand Diagrams in Carpal Tunnel Syndrome Screening. JHS, 2012.

 Sensitivity: 40%  Specificity: 80%  Long finger: 67/73 Utility of Physical Examination in Predicting Disorder

 Thenar wasting is hard to measure: hand deformities  Thumb abduction strength is hard to measure: baseline, abductor pollicis longus Whom to Start Treatment and Whom to Consider Study Early

 Start Treatment  Clear triggers  Periodic and not continuous  Morning symptoms only  Study Early  Constant symptoms  Thenar atrophy  Thumb abduction weakness Common Mimics and Co-Incident Disorders

 1st MCC arthritis  Local deformity and tenderness  Weakness vs. pain with resistance  Co-incident: both related to repetitive UE work or activities  DeQuervain’s tenosynovitis  Lateral thumb and forearm tenderness  No sensory symptoms  Pain with thumb adduction and opposition  Co-incident: both related to repetitive UE work or activities  Flexor tenosynovitis  Ulnar neuropathy at the elbow  Cervical radiculopathy: C6  Upper trunk brachial plexopathy  Unusual Presentations  Inclusion Body Myositis  Myotonic Dystrophy  ALS Effective First Line Treatments

 Hand splints  NSAID’s  Hand occupational therapy NCS before Invasive Line Treatments

 Comparative Testing to eliminate impact of age, temperature, height, and superimposed conditions (polyneuropathy)  Sensory comparative: Sensitivity 0.85, specificity 0.97  Motor: Sensitivity 0.63, specificity 0.98  Temperature correction is critical in making the correct diagnosis  Severe CTS: CMAP amplitude drop or abnormal needle exam study  Population studies  21% with surgery without NCS  14.5% with less than two sensory studies  10.6% with less than two motor studies  6.1% neither Role of Imaging In Diagnosis of CTS

Test AUC Sensitivity Specificity

EMG Comp Sensory 0.923 90.9 81.2

U/S UPA/UDA 0.751/0.912 88.4/83.7 46.2/76.9

UPE/UDE 0.798/0.835 76.7/86.0 76.9/78.6

CT CPA/CDA 0.838/0.874 97.1/67.6 46.7/86.7

CPD/CDD 0.803/0.798 67.6/70.6 80/75

MRI MPA/MDA 0.823/0.847 42.5/65 100/80

MPI/MDI 0.813/0.722 87.5/87.5 60/40 Effectiveness of Injection for Carpal Tunnel Syndrome Blazar PE. Prognostic Indicators for Recurrent Symptoms After a Single Corticosteroid Injection for Carpal Tunnel Syndrome. JBJS (A), 2015.  53% symptom free for 6 months, 31% for one year  Repeat injection 81% symptom free at 6 months, 66% at one year  35% operation rate in the first year  Concomitant diabetes best predicted failure of injection therapy  2.6 fold greater risk of reporting symptom recurrence Blind Vs. Ultrasound Guided Injection Eslamian F. A Randomized Prospective Comparison of Ultrasound-Guided and Landmark-Guided Steroid Injections for Carpal Tunnel Syndrome. J Clin Neurophys, 2017.

 No difference in change in symptoms  No difference in electrophysiological parameters When That Does Not Work: Surgical Referral Effectiveness of CTS Surgery

 10-15% with unsatisfactory outcomes in most studies  Most severe patients with delayed improvement due to axonal loss  Lack of improvement at one year  Initial improvement followed by recurrence of symptoms  Re-operation rates 5-12%  Clear evidence that CTS Surgery effectiveness is negatively impacted by a negative EMG study  Fact is amplified in patients with worker’s compensation  BEWARE: yellow flags Effectiveness of CTS Surgery: Who did best Lo YL. Outcome Prediction Value of Nerve Conduction Studies for Endoscopic Carpal Tunnel Surgery. J Clin NM Disease, 2012.

 Sensory peak latency less than 6.0 ms (13 cm distance)  VAS 0-10 paresthesia score of 4 or higher  Patients with lower paresthesia scores did not do as well  Pain, numbness and weakness scores were not predictive  75% noted improved paresthesias and numbness, 52% for weakness and 34% for pain  In other words: moderate disease and sensory symptoms where pain is not a significant symptom CTS Surgery Complications

 Nerve injury 0.05%  Wound infection 0.36% (deep 0.13%)  Tendon injury 0.1%  Pillar pain: self limited to 6-9 months  Pisotriquetral joint pain  CRPS CTS Surgery Failures: What is next?

 Re-operation in 5-12 %  Incomplete release  Scar formation  Incorrect diagnosis  Re-operation rate improvement about 50%  BEWARE: yellow flags Does Double Crush Exist? Garcia-Santibanez R. Scelsa SN. Frequency of Radiculopathy in Patients With Carpal Tunnel Syndrome and Paracervical Pain. J. Clin NM Dis 2016.

 Patients with CTS and paracervical pain are not any more likely to have cervical radiculopathy than patients with CTS alone.  Nerve conduction study parameters of CTS severity are not at all related to whether a patient has cervical radiculopathy (no dose effect) Risk of developing CTS with abnormal nerve conduction studies Werner RA. Use of screening nerve conduction studies for predicting future carpal tunnel syndrome. Occ Env Med 1997.

 At risk employees without characteristic symptoms but abnormal nerve conduction studies  Factory workers  Dental hygienists  Increased risk over 7-11 years compared to aged matched controls  Only 25% became symptomatic in that time frame Questions