First rib dysfunction in patients with neck and shoulder pain: a Delphi investigation

Key points

1. 01Consensus (>70% agreement) identified first rib mobility restriction as the defining feature of the dysfunction
2. 02A cluster of clinical tests is required for diagnosis; no single test is sufficient
3. 03Experts proposed two subgroups: first rib as a primary dysfunction and as a contributing factor in upper limb neurodynamic problems
4. 04The cervical rotation lateral flexion (CRLF) test was considered useful only within a broader cluster of findings, with its standalone validity questioned
5. 05Experts estimated first rib dysfunction is a primary problem in fewer than 10% of neck/shoulder patients, but a contributing factor in 20-30%

How it was conducted

Design

Four-round Delphi consensus survey

Participants

16 international manual therapy experts from 11 countries with at least 10 years of musculoskeletal manual therapy experience and/or IFOMPT-standard OMPT training

Response rate

35% of 45 invited experts agreed to participate; 12/16 completed round one, 10/12 completed round four

Consensus threshold

>70% agreement defined consensus; >50% defined near-consensus

Items analyzed

180 items from round one condensed to 134, organized into 10 themes, yielding 102 items across 17 themes in subsequent rounds

Primary outcome

Consensus-related (CR) clinical items for identifying first rib dysfunction

What they found

• 65 items reached Consensus Related (53) or near Consensus Related (12) status across five broad domains
• Experts reached consensus that first rib dysfunction is a primary problem in fewer than 10% of neck/shoulder patients (composite score 45, CR)
• Experts reached consensus that it is a contributing factor in 20-30% of neck/shoulder patients (composite score 50, CR)
• Longitudinal caudad accessory movements of first rib painful and restricted reached the highest composite score of 56 (CR)
• Palpation of first rib painful reached composite score 55 (CR)
• Positive upper limb neural test 1 (ULNT 1) reached composite score 46 (CR)
• Improvement after mobilization of first rib reached composite score 51 (CR)
• CRLF test item 'I don't use it' reached composite score 39 (CR) while 'useful tool to identify first rib dysfunction' also reached CR at composite score 26, reflecting divided opinion
• Interexaminer reliability of the CRLF test was reported as kappa 0.5 to 1.0 in prior literature; intermethod reliability with cineradiography was kappa 0.84 in a single study
• 3 items reached Consensus Non-Related status; 34 items were undecided

Limitations

• Delphi methodology captures expert opinion, not clinical evidence; findings cannot be verified against empirical data
• Low response rate (35%) and small final panel (10-12 experts per round) limit generalizability
• Approximately two-thirds of participants were International Maitland Teachers Association members, introducing potential training-perspective bias
• The study did not establish whether first rib dysfunction as a clinical entity actually exists, nor did it test the reliability or validity of the proposed cluster

Why it matters

For patients

Patients with unexplained neck, shoulder, or arm symptoms may benefit from clinicians considering first rib dysfunction as part of a broader assessment, though no validated diagnostic test yet exists.

For clinicians

Clinicians should apply a cluster of findings, including first rib accessory movement testing, palpation, upper limb neural testing, and cervical movement assessment, rather than relying on the CRLF test alone, while awaiting formal validity studies.

For readers

This Delphi study maps expert opinion on an under-researched condition and highlights the urgent need for prevalence, reliability, and validity research before these criteria can be recommended for widespread practice.