Midcarpal Instability Test

What is the Midcarpal Instability Test?

Midcarpal instability (MCI) refers to a range of wrist joint dysfunctions involving excessive or abnormal movement in the proximal carpal row and distal carpal rows. Common symptoms include ulnar-sided wrist pain, a sense of weakness or instability, and sometimes a distinctive “clunk” as the wrist moves into ulnar deviation. MCI often results from repetitive stress or trauma, leading to conditions like palmar midcarpal instability (PMCI), dorsal midcarpal instability, or extrinsic midcarpal instability.

The midcarpal shift test, also known as the Lichtman test, is commonly used to evaluate MCI. Named after David Lichtman, this test places a palmarly directed force on the distal carpal row as the wrist moves into radial deviation and ulnar deviation. This maneuver stresses the arcuate ligament and other supporting structures, potentially revealing instability when a clunk or abnormal shift occurs.

MCI falls under Carpal Instability Nondissociative (CIND), a broad category that also includes conditions like volar intercalated segmental instability (VISI). In VISI, the carpal bones on the palm side shift downward, creating a specific pattern of instability. Midcarpal instability can also involve weakened ligaments, such as the dorsal radiocarpal ligament, leading to inconsistent control over the carpal bones and resulting in a distinct wrist joint dysfunction.

How to use our Midcarpal Instability Test template

Our Midcarpal Instability Test template provides healthcare professionals with a structured format to document the assessment, results, and recommendations for patients undergoing this test. The template includes blank fields for observations, ensuring personalized documentation that supports clear communication and follow-up care.

Step 1: Access the template

Open the Midcarpal Instability Test template by clicking "Use template" to access it directly in the Carepatron app, where you can customize, share, and save your entries. Alternatively, you can save a fillable, non-customizable PDF by clicking "Download."

Step 2: Administer the test

Guide the patient to sit in front of you with their forearm pronated and the wrist in a neutral position (which was used in Feinstein and colleagues' review in 1999) or slight radial deviation (used in Prosser and colleagues' review in 2015). Place your thumb over the dorsum of the distal capitate bone, stabilizing the forearm with your other hand. Apply a palmarly-directed force to the wrist, allowing the carpus to translate palmarly, which stresses the arcuate ligament. While maintaining this pressure, ulnarly deviate the wrist to observe for a clunking sensation as the wrist approaches full ulnar deviation. Repeat the procedure with the wrist in slightly supine and pronated positions to ensure comprehensive assessment.

Step 3: Interpret the results

Evaluate the patient's response to the test. Record findings such as pain, clunking, or instability, and classify the results as positive or negative based on the observed signs.

Step 4: Discuss with the patient

Explain the findings to the patient, providing clarity on the results and any recommendations for further care. Use the template to highlight areas needing attention, discuss management options, and answer any questions the patient may have.

Scoring and interpretation

A positive result in the Midcarpal Instability Test occurs when the patient experiences pain or a clunking sensation as the wrist is ulnarly deviated. This finding typically indicates instability within the midcarpal joint, often due to issues with the arcuate or dorsal radiocarpal ligament. A negative result, where pain and clunking are absent, suggests that midcarpal instability is unlikely. It is highly recommended to do other tests, such as physical examinations, imaging, or provocative tests, to confirm diagnosis and rule out other issues.

How to address midcarpal instability

Treatment options for midcarpal instability vary depending on the severity of the condition, ranging from conservative to surgical approaches. Here are some effective options:

• Physical therapy: Structured exercises focus on strengthening the wrist and improving proprioception, especially beneficial for cases of Carpal Instability Nondissociative (CIND), where instability affects the distal carpal row without dissociation between individual carpal bones.
• Splinting: For pain relief and stabilization, wrist splints are often recommended to limit motion and reduce strain on the ligaments, providing support during daily activities.
• Wrist arthroscopy: In cases where conservative approaches are insufficient, wrist arthroscopy allows for minimally invasive assessment and treatment of the distal carpal rows, enabling targeted correction and repair of instability.
• Ligament reconstruction: Severe cases may require ligament reconstruction using a palmaris longus tendon graft to replace or reinforce damaged ligaments, providing lasting stability to the wrist joint.

Each intervention option should be selected based on individual assessment, considering factors such as the extent of instability and the patient's activity level and overall health.

Benefits of conducting this test

The Midcarpal Instability Test offers several important benefits:

• Accurate diagnosis: Helps identify subtle forms of wrist instability, including palmar midcarpal instability.
• Guides treatment: Assists healthcare providers in determining the best course of intervention, from conservative measures to surgical options.
• Improves patient outcomes: Early detection and proper diagnosis lead to better, more effective management strategies.

References

Feinstein, W. K., Lichtman, D. M., Noble, P. C., Alexander, J. W., & Hipp, J. A. (1999). Quantitative assessment of the midcarpal shift test. The Journal of Hand Surgery, 24(5), 977–983. https://doi.org/10.1053/jhsu.1999.0977

Prosser, R., Harvey, L., LaStayo, P., Hargreaves, I., Scougall, P., & Herbert, R. D. (2011). Provocative wrist tests and MRI are of limited diagnostic value for suspected wrist ligament injuries: A cross-sectional study. Journal of Physiotherapy, 57(4), 247–253. https://doi.org/10.1016/s1836-9553(11)70055-8