Published Comment in the Annals of Internal Medicine Regarding Subacromial Impingement

Comments and Responses
Management of the Unilateral Shoulder Impingement Syndrome

TO THE EDITOR: On the surface, Rhon and colleagues’ thoughtful study (1) shows the effectiveness of subacromial corticosteroid injection and manual physical therapy to treat the shoulder impingement syndrome (SIS). However, several factors complicate the comparison of manual physical therapy with medical intervention and perhaps limit this study’s otherwise valuable contribution.

First, the manual therapy approach used in this study was well-described here and elsewhere (2).  However, physical therapists in clinical practice typically assess the presence and quality of symptoms in relation to patient movement and position, not according to a pathoanatomical diagnosis such as SIS; therefore including the manual therapy intervention as a treatment for SIS may be misleading.  Emphasis should have been placed on the idea that manual therapy is a treatment for the mechanical stresses that may lead to SIS, while a corticosteroid injection has a more direct effect on the structures that have been injured.  

Second, manual physical therapists continually reassess and adjust treatment on the basis of the patient’s symptomatic changes structured as a test–retest model (establish a baseline, do an intervention, and then retest to look for change from the baseline). This model has been validated (3) and is the common thread linking many assessment approaches used by all types of physical therapists. This model differs from a physician’s typical assessment and treatment in that therapists spend more time (generally 2 to 3 sessions weekly for at least 4 weeks) observing patients move and their response to various noninvasive interventions.

Third, this study may not have sufficiently emphasized the patient education process. Many musculoskeletal conditions involving the shoulders have high recurrence rates (4), particularly when the mechanism of injury is progressive and thought to result from repetitive overuse of the injured area. In these frequent cases, resolution and recurrence of symptoms may simply be part of the natural history of the condition; short-term pain control and improved functionality would not be the ultimate goal of intervention. Physical therapists educate their patients to become their own “self-assessors” and learn how and when to use appropriate self-treatment techniques as developed through the assessment approach used when deciding on suitable manual techniques.

Finally, corticosteroid injection and manual physical therapy often work in synergy: The former decreases inflammation, and the latter decreases the mechanical stress that may have caused the symptoms in the first place. Including a third group that received both interventions might have allowed for a more clinically relevant comparison.

Christopher Leib, DPT, CSCS, Cert MDT, COMT
Pain Relief and Physical Therapy; Havertown, Pennsylvania

Disclosures: Authors have disclosed no conflicts of interest. Forms can be viewed at www.acponline.org/authors/icmje/ConflictOfInterestForms.do?msNum=L14-0450.

References
1. Rhon DI, Boyles RB, Cleland JA. One-year outcome of subacromial corticosteroid injection compared with manual physical therapy for the management of the unilateral shoulder impingement syndrome: a pragmatic randomized trial. Ann Intern Med. 2014;161:161-9. [PMID: 25089860] doi:10.7326/M13-2199
2. Rhon DI, Boyles RE, Cleland JA, Brown DL. A manual physical therapy approach versus subacromial corticosteroid injection for treatment of shoulder impingement syndrome: a protocol for a randomised clinical trial. BMJ Open. 2011;1:e000137. [PMID: 22021870] doi:10.1136/bmjopen-2011-000137
3. Cook CE, Showalter C, Kabbaz V, O'Halloran B. Can a within/between-session change in pain during reassessment predict outcome using a manual therapy intervention in patients with mechanical low back pain? Man Ther. 2012;17:325-9. [PMID: 22445052] doi:10.1016/j.math.2012.02.020
4. Luime JJ, Koes BW, Miedem HS, Verhaar JA, Burdorf A. High incidence and recurrence of shoulder and neck pain in nursing home employees was demonstrated during a 2-year follow-up. J Clin Epidemiol. 2005;58:407-13. [PMID: 15862727]