History-taking and Physical Examination are generally accepted, well-established, and widely used procedures which establish the foundation/basis for and dictate all ensuing stages of diagnostic and therapeutic procedures. When findings of clinical evaluation and those of other diagnostic procedures do not complement each other, the objective clinical findings should have preference.
Figure 1 - Katz Hand Diagram Used with permission. JAMA 2000; 283 (23): 3110-17. Copyrighted 2000, American Medical Association.
Table 1: Sensitivities and Specificities and Evidence Level for Physical Examination findings
Procedure | Sensitivity (%) | Specificity (%) | Validity |
1. Sensory testing | |||
Hypesthesia | 15-51 | 85-93 | Good |
Katz Hand Diagram | 62-89 | 73-88 | Good |
Two-point discrimination | 22-33 | 81-100 | Some |
Semmes-Weinstein | 52-91 | 59-80 | Some |
Vibration | 20-61 | 71-81 | None |
2. Phalen's | 51-88 | 32-86 | Some |
3. Tinel's | 25-73 | 55-94 | Some |
4. Carpal tunnel compression | 28-87 | 33-95 | Some |
5. Thenar atrophy | 3-28 | 82-100 | Good |
Abductor pollicis brevis weakness | 63-66 | 62-66 | Good |
6. Closed fist test | 61 | 92 | Some |
7. Tourniquet test | 16-65 | 36-87 | None |
No single epidemiologic study will fulfill all criteria for causality. The clinician must recognize that currently available epidemiologic data is based on population results, and that individual variability lies outside the scope of these studies. Many published studies are limited in design and methodology, and, thus, preclude conclusive results. Most studies' limitations tend to attenuate, rather than inflate, associations between workplace exposures and CTS.
These guidelines are based on current epidemiologic knowledge. As with any scientific work, the guidelines are expected to change with advancing knowledge. The clinician should remain flexible and incorporate new information revealed in future studies.
Table 2: Risk Factors Associated with Carpal Tunnel Syndrome
Diagnosis | Strong Evidence | Good evidence | Some evidence | Insufficient or conflicting evidence |
Carpal Tunnel Syndrome | Combination of high exertional force (Varied from greater than 6 kg) and high repetition (work cycles less than 30 sec or greater than 50% of cycle time performing same task, length of shortest task less than 10 sec). | Repetition or force independently, use of vibration hand tools. | Wrist ulnar deviation and extension. | Pinch/grip, keyboarding. |
The Department recommends the above diagnostic procedures be considered, at least initially, the responsibility of the workers' compensation carrier to ensure that an accurate diagnosis and treatment plan can be established.
19 Del. Admin. Code § 1342-A-4.0