Recommended Outcome Measures for Frozen Shoulder
The Shoulder Pain and Disability Index (SPADI) is the recommended primary outcome measure for frozen shoulder due to its demonstrated satisfactory reliability and validity properties in patients with idiopathic frozen shoulder. 1
Primary Outcome Measures
The SPADI shows high test-retest reliability with intraclass correlation coefficients of 0.989 for pain and 0.990 for disability subscales, making it an excellent choice for monitoring frozen shoulder progression and treatment response 1
The SPADI demonstrates good internal consistency for both pain (α = 0.859) and disability (α = 0.895) subscales, ensuring the measure accurately captures the multidimensional impact of frozen shoulder 1
Construct validity of SPADI is satisfactory, with seven out of eight expected correlations with other validated measures being satisfied, confirming its ability to accurately measure the intended constructs 1
Range of Motion Assessment
Range of lateral rotation has been identified as the factor most significantly related to shoulder pain onset and should be prioritized in assessment 2
The classic capsular pattern involves greatest limitation in external rotation, followed by abduction, and then internal rotation - this pattern should be documented to track progress 2
Measurement of active range of motion should focus on flexion, abduction, external rotation, and internal rotation to comprehensively assess functional limitations 3
Supplementary Outcome Measures
Patient-reported outcome measures (PROMs) should be included alongside objective measurements to capture the patient's subjective experience of disability and pain 3
The Disabilities of the Arm, Shoulder and Hand Questionnaire (DASH) can be used as a complementary measure as it has shown good correlation with SPADI in frozen shoulder patients 1
The Numerical Pain Rating Scale (NPRS) should be incorporated to specifically track pain intensity, which is a primary concern in the painful phase of frozen shoulder 1
Timing of Assessment
Outcome measures should be administered at baseline and at regular intervals throughout treatment to track progress 4
The American College of Sports Medicine recommends early assessment and intervention to prevent progression to more severe frozen shoulder 2
For clinical trials, follow-up assessments should be conducted at short-term (≤12 weeks), mid-term (>12 weeks to ≤12 months), and long-term (>12 months) intervals to capture the full trajectory of recovery 4
Clinical Application
The SPADI has established minimal detectable change values of 6.27 for pain and 6.25 for disability subscales, providing clinicians with thresholds for meaningful clinical improvement 1
When evaluating treatment efficacy, improvements in both pain and function domains should be considered, as these may respond differently to various interventions 4
For patients with diabetes, who have a higher risk of developing and recurring frozen shoulder, more frequent outcome assessment may be warranted 5
Common Pitfalls to Avoid
Avoid relying solely on range of motion measurements without incorporating patient-reported outcomes, as this fails to capture the full impact of frozen shoulder on quality of life 1, 4
Be aware that some patients may experience long-term disabilities despite treatment, necessitating ongoing assessment beyond the typical recovery timeframe 6
Ensure that outcome measures are administered consistently by the same evaluator when possible to minimize measurement variability 1