Related Experiment Video
Updated: Mar 14, 2026
Screening of Axonal Degeneration in Carpal Tunnel Syndrome Using Ultrasonography and Nerve Conduction Studies
Published on: January 11, 2019
The rational clinical examination. Does this patient have clubbing?
1Queen's University, Hotel Dieu Hospital, 166 Brock St, Kingston, Ontario, Canada K7L 5G2. myersk@hdh.kari.net
Insights
Digital clubbing, a sign of various diseases, can be identified using specific measurements. The profile angle and phalangeal depth ratio are recommended quantitative indices for accurate clinical assessment.
Area of Science:
- Medical Diagnostics
- Clinical Examination
- Pulmonology
Background:
- Digital clubbing has been linked to numerous diseases since antiquity.
- While advanced clubbing is recognizable, early clubbing often presents diagnostic challenges.
Purpose of the Study:
- To systematically review literature on the precision and accuracy of clinical examination for digital clubbing.
- To identify reliable quantitative indices for diagnosing clubbing.
Main Methods:
- Conducted a systematic literature review of MEDLINE and bibliographies from 1966 to 1999.
- Included 16 studies with quantitative or qualitative assessments of clubbing in patients.
- Extracted data on quantitative indices, examination precision, and disease association accuracy.
Main Results:
- Profile angle (>176°), hyponychial angle (>192°), and phalangeal depth ratio (>1.0) serve as quantitative indices for clubbing.
- Interobserver agreement for bedside assessment of clubbing is variable (kappa 0.39–0.90).
- Clubbing is a marker for lung cancer (LR 3.9) and inflammatory bowel disease (LR 2.8–3.7).
Conclusions:
- Recommends using the profile angle and phalangeal depth ratio for identifying digital clubbing.
- Emphasizes clinical judgment for further investigation when indices exceed 180° and 1.0, respectively.
Context:
The association between digital clubbing and a host of diseases has been recognized since the time of Hippocrates. Although the features of advanced clubbing are familiar to most clinicians, the presence of early clubbing is often a source of debate.
Objective:
To perform a systematic review of the literature for information on the precision and accuracy of clinical examination for clubbing.
Data Sources:
The MEDLINE database from January 1966 to April 1999 was searched for English-language articles related to clubbing. Bibliographies of all retrieved articles and of standard textbooks of physical diagnosis were also searched.
Study Selection:
Studies selected for data extraction were those in which quantitative or qualitative assessment for clubbing was described in a series of patients. Sixteen studies met these criteria and were included in the final analysis.
Data Extraction:
Data were extracted by both authors, who independently reviewed and appraised the quality of each article. Data extracted included quantitative indices for distinguishing clubbed from normal digits, precision of clinical examination for clubbing, and accuracy of clubbing as a marker of selected diseases.
Data Synthesis:
The profile angle, hyponychial angle, and phalangeal depth ratio can be used as quantitative indices to assist in identifying clubbing. In individuals without clubbing, values for these indices do not exceed 176 degrees, 192 degrees, and 1.0, respectively. When clinicians make a global assessment of clubbing at the bedside, interobserver agreement is variable, with kappa values ranging between 0.39 and 0.90. Because of the lack of an objective diagnostic criterion standard, accuracy of physical examination for clubbing is difficult to determine. The accuracy of clubbing as a marker of specific underlying disease has been determined for lung cancer (likelihood ratio, 3.9 with phalangeal depth ratio in excess of 1.0) and for inflammatory bowel disease (likelihood ratio, 2.8 and 3.7 for active Crohn disease and ulcerative colitis, respectively, if clubbing is present).
Conclusions:
We recommend use of the profile angle and phalangeal depth ratio as quantitative indices in identifying clubbing. Clinical judgment must be exercised in determining the extent of further evaluation for underlying disease when these values exceed 180 degrees and 1.0, respectively.
Related Concept Videos
01:21Peripheral Arterial Disease II: Clinical Manifestations and Diagnostic Evaluation
01:25Assessment of apical radial pulse
The A-R pulse assessment involves simultaneous evaluation of the apical and radial pulses. When the apical and radial pulse rates vary, this assessment helps identify a pulse deficit.
Pre-Procedural Preparation
01:11Assessment of radial pulse
The radial pulse, located at the wrist, is often the preferred site for assessing peripheral pulse because of its accessibility and dependability. The process of determining the radial pulse involves several steps:
01:29Cardiovascular System Abnormal Findings I: Inspection and Palpation
Abnormal findings observed during an inspection
01:27Assessment of the Cardiovascular System III: Palpation
Jugular Venous Pressure (JVP) Measurement
Position the patient at a thirty- to forty-five-degree angle or in a semi-fowler's position. Look for the highest point of pulsation in the internal jugular vein and measure the vertical distance to the angle of Loius or sternal angle. A normal JVP is 3-4 cm above...
01:17Assessment of apical pulse
Assessing the apical pulse is a critical nursing procedure, particularly indicated for: