NMM/OMTBRIEF REPORT
Abstract
Context: Osteopathic manipulative treatment (OMT) has been recognized as a conservative management option for patients with carpal tunnel syndrome (CTS), although limited research exists to validate its ability to effect posttreatment changes in the median nerve or the surrounding soft tissues.
Objectives: The objectives of this study are to evaluate and quantify changes in the elasticity of the median nerve, transverse carpal ligament (TCL), and intracarpal tunnel soft tissues in patients treated for CTS with traditional conservative therapy (e.g., steroid injection and splinting), OMT, or OMT plus conservative therapy.
Methods: This single-blinded, randomized controlled pilot study included patients with a definitive diagnosis of mild to moderate-severe CTS. Participants were assigned to one of the three treatment groups utilizing a random number generator. Analysis of variance (ANOVA) was conducted to compare the following outcome measures from baseline through 6 weeks of treatment across the three groups of interest: the CTS-6 assessment tool and the shortened version of the Disabilities of the Arm, Shoulder, and Hand (Quick-DASH) questionnaire, electromyography (EMG) of the median nerve, grayscale ultrasound evaluation of the cross-sectional area (CSA) of the median nerve, and shear wave elastography (SWE) of the median nerve, TCL, and the intracarpal tunnel contents (ICTC). Associations between EMG severity scores, CTS-6 assessments, and Quick-DASH scores were also explored through correlation analyses.
Results: Among the 15 wrists randomized to the study, 5 withdrew, primarily due to the inability to complete all follow-up visits. 10 wrists completed the study: 3 in the conservative group, 4 in the OMT group, and 3 in the OMT plus conservative group. Ultrasound and SWE were effective in measuring median-nerve CSA and stiffness, although changes through 6 weeks were generally limited. There was no significant difference in the CSA measurements of the median nerve throughout the study (p=0.22, 0.11, 0.18, and 0.71 at weekly visits 1, 3, 5, and 7, respectively). Only the conservative therapy group showed notable reductions in CSA and stiffness over time, which corresponded to statistically nonsignificant reductions in CTS-6 survey scores (ANOVA analysis at visit 6 producing p=0.35) and Quick-DASH scores (p=0.12). One ANOVA analysis of the TCL average shear velocity did produce significant results at visit 7 (OMT mean=4.1, combination mean=3.5, conservative mean=3.7, p=0.01). Changes in EMG parameters (amplitude, latency, and conduction velocity of the median nerve) from baseline through 6 weeks were variable, with no clear pattern of change in any group. Similarly, there was weak association between EMG severity scores and CTS-6 (R2=0.1463) and Quick-DASH scores (R2=0.4676).
Conclusions: History and clinical examination are the primary means of establishing the diagnosis of CTS, with EMG and imaging playing supportive roles. The use of grayscale ultrasound and SWE as alternative, noninvasive diagnostic means in establishing a diagnosis of CTS continues to be explored. Given that SWE can serve as a reproducible, noninvasive, and objective means of evaluating the stiffness of soft tissues prior to and following various forms of treatment, further studies should be undertaken to investigate its utility and value in providing objective evidence of the efficacy of OMT.