First rib palpation using anatomical landmarks
Accurate surface palpation is essential in practice both diagnostically and therapeutically and depends on effective localization using anatomical references. The first rib comprises the floor of the thoracic outlet costoclavicular space and serves as the attachment point for several key muscles implicated in thoracic outlet syndrome and cervicothoracic dysfunction.
Previous studies have shown that the first rib can become “stuck” in an elevated position and that restoring of both position and movement can help alleviate Thoracic Outlet Syndrome (TOS) type symptoms. In order to effectively treat the first rib the clinician must first be able to systemically localize it.
Considering these things, the authors of the current study set out to investigate an unverified but readily used relationship between the C1 and T1 transverse process (transverse process) for localizing the first rib. In addition to this they sought to determine other potential reference points for accurately localizing the 1st rib. Overall it was shown that both the C1 TP and mastoid process (MP) would be effective landmarks for determining the width of the first rib articulation.
Twenty eight cadavers (14 male, 14 female) were investigated. Overlying tissues covering the MP, C1 TP and T1 TP were removed bilaterally. Data collection consisted of span measurements at C1 TP, T1 TP and MP. Cadavers were excluded in the presence of cervical fusion or if a cervical rib was observed.
The results of the study support the use of the C1 TP span for first rib localization as well as the mastoid process. Mean difference T1-TP to first rib was 3.9mm (ICC 0.88) and mean difference between MP and T1 was 35.4mm (ICC 0.71). The mastoid is consistently slightly lateral to the costotransverse joint at the first rib.
Considering this the authors propose that the mastoid process would be a more accurate surface reference for localizing the first rib as the practitioner does not run the risk of mistakenly palpating and mobilizing the T1 TP rather than the first rib.
> From: Loyd et al., J Man Manip Ther 22 (2016) 129-133(Epub ahead of print). All rights reserved to W.S. Maney & Son Ltd. Click here for the Pubmed summary.