Posterior Shoulder Tightness: To Treat or Not to Treat?

Combined Effects of Glenohumeral Mobilization, Stretching, and Thoracic Manipulation on Shoulder Internal Rotation Range of Motion

Background/purpose

Interventions including posterior glenohumeral mobilizations (PGM), sleeper stretches, and thoracic manipulation are commonly used to address posterior shoulder tightness. The purpose of this study was to assess the effects of adding thoracic manipulation to PGM and sleeper stretches on passive range of motion (PROM), joint mobility, and infraspinatus electromyographic (EMG) activity in shoulders with decreased internal rotation (IR) PROM.

Design

Randomized Sequential Intervention Laboratory Study.

Methods

Forty individuals with clinically significant IR loss attended two study sessions. Participants were randomized to receive five 30 seconds bouts of either grade III PGM or sleeper stretching. Following a seven-day washout period, all participants attended a second session and received a prescriptive supine HVLA manipulation targeting the T3-4 segment, followed by the previously randomized intervention. Outcome measures included internal rotation PROM, horizontal adduction PROM, posterior glenohumeral joint translation assessed via ultrasound imaging, and EMG activity of the infraspinatus during a PGM. All outcome measures were assessed pre- and immediately post-intervention and compared statistically.

Results

There were significant within-group, but not between-group, differences for IR and horizontal adduction PROM following a single session of PGM or sleeper stretch. When combined with thoracic manipulation, significantly smaller within session changes of IR PROM were observed for both PGM (mean difference 4.4, p=0.017) and sleeper stretches (mean difference 6.4, p=0.0005). There were no significant between group differences for horizontal adduction PROM, humeral head translation, or EMG activity across all time points.

Discussion

Both GH posterior mobilizations and sleeper stretches improved IR and horizontal adduction PROM in a single session. The addition of thoracic manipulation prior to local shoulder interventions resulted in smaller gains of both IR and horizontal adduction ROM.

Level of evidence

Level 2.

An evidence-informed rehabilitation management framework for posterior shoulder tightness: A scoping review

Objective

To systematically scope the literature on posterior shoulder tightness (PST) and define a therapist-instructed and therapist-administered management framework.

Design

Scoping review.

Literature search

We searched MEDLINE, EMBASE, CINAHL, Scopus and Google Scholar from inception to December 2021.

Study selection criteria

Peer-reviewed studies written in English, French, Greek, Japanese or Tamil, with extractable pre- and post-intervention data. Physiotherapy interventions amenable for posterior shoulder structural (muscle, capsule) causes of PST within an adult population.

Data synthesis

Arksey and O'Malley's framework was implemented and the PRISMA extension for scoping reviews directed our data synthesis. The data charted from each study included authors, title, study year, location, study design; participant number, age, sex; PST intervention and parameters; patient-reported outcomes; and results. Themes were organized into therapist-instructed and therapist-administered rehabilitation strategies, as well as combined treatment methods.

Results

Of 2777 articles identified from our search strategy, 21 articles were included. Therapist-instructed interventions included cross-body stretch (CBS), sleeper stretch (SS), a combination of the two and general stretching. Therapist-administered interventions included CBS, SS, instrument-assisted soft tissue mobilization (IASTM), muscle energy techniques, dry needling and Fauls protocol (12 therapist-assisted stretches). Combined interventions of tape with self-stretching and IASTM and stretching were also identified.

Conclusion

Based on the current evidence, CBS and SS are the most researched treatments for PST and seem to be effective at improving PST. Furthermore, stabilization of the scapula while performing these stretches optimized the stretch targeted to the PST and ROM benefits for horizontal adduction.

No Evidence of Short-term Changes in Muscle Activity Elicited by Dry Needling in Chronic Unilateral Shoulder Pain Patients

OBJECTIVE

The aim of the study was to assess short-term changes in shoulder muscle activity elicited by dry needling in chronic unilateral shoulder pain (USP) patients.

METHODS

A randomized, double-blind, placebo-controlled clinical trial was conducted, in which 30 volunteers with USP were recruited and randomly assigned to either real or sham dry needling conditions. Pain intensity scores, pressure pain threshold, glenohumeral internal rotation angles, and electromyographic activity during isotonic shoulder tasks (shoulder flexion and extension) were assessed before, immediately, and 72 hours after the intervention in the infraspinatus and deltoid muscles.

RESULTS

A single application of real dry needling resulted in lower pain intensity scores and a larger range in glenohumeral internal rotation 72 hours after the intervention in comparison with sham dry needling. No differences in pressure pain threshold or muscle activity were observed due to the intervention.

DISCUSSION

A single application of real dry needling resulted in clinically significant changes in the short term. No differences were detected in muscle activation in the infraspinatus or deltoid muscles. Complementary interventions and longer follow-up times may be required to observe changes in muscle activity.

Effective stretching position for the posterior deltoid muscle evaluated by shear wave elastography

BACKGROUND

Deteriorated extensibility of the posterior deltoid muscle is one of the factors of posterior shoulder tightness, and improvement in its extensibility is needed. However, no study has investigated which shoulder positions effectively stretch the posterior deltoid muscle in vivo. The aim of this study was to verify the effective stretching position of the posterior deltoid muscle in vivo by shear wave elastography.

METHODS

Fifteen healthy men participated in this study. The shear modulus of the posterior deltoid was measured at resting and 13 stretching positions: 60°, 90°, and 120° shoulder flexion; maximum shoulder flexion, horizontal adductions at 60°, 90°, and 120° shoulder flexion; internal rotations at 60°, 90°, and 120° shoulder flexion; and combinations of horizontal adduction with internal rotation at 60°, 90°, and 120° shoulder flexion. The shear moduli of each stretching position were compared to those of the rest. Then, among the stretching positions for which the shear modulus was significantly different from the rest, the shear moduli were compared using a three-way analysis of variance with repeated measures of the 3 factors-flexion, horizontal adduction, and internal rotation.

RESULTS

The shear moduli in all stretching positions were significantly higher than those of the rest, except for maximum shoulder flexion. The three-way analysis of variance with repeated measures revealed significant main effects in flexion and horizontal adduction. Comparing the flexion angles, the shear modulus was significantly higher at 90° than that at 60° and 120°. The shear modulus with horizontal adduction was significantly higher than that without horizontal adduction. Moreover, a significant two-way interaction was found only at flexion and horizontal adduction. The shear modulus with horizontal adduction was significantly higher at all angles than that without horizontal adduction at each flexion angle. Comparing the flexion angles with horizontal adduction, the shear modulus was significantly higher at 90° than that at 60° and 120°. No significant three-way interactions were found.

CONCLUSION

Shoulder flexion and horizontal adduction affected the extensibility of the posterior deltoid muscle, whereas the effect of shoulder internal rotation was limited. More precisely, maximal horizontal adduction at 90° shoulder flexion was the most effective stretching position for the posterior deltoid muscle.

The Effects of Instrument-Assisted Soft Tissue Mobilization, Tissue Flossing, and Kinesiology Taping on Shoulder Functional Capacities in Amateur Athletes

CONTEXT

Instrument-assisted soft tissue mobilization (IASTM), tissue flossing, and kinesiology taping are increasingly popular treatments among athletes for improving functional performance, despite limited evidence for their efficacy.

OBJECTIVE

Previous research regarding the efficacy of soft tissues and neuromuscular techniques on improving functional capacity of shoulder joints in athletes has yielded conflicting results. We examined the immediate and short-term effects of IASTM, flossing, and kinesiology taping on the functional capacities of amateur athletes' shoulders.

DESIGN

Randomized controlled study.

SETTING

Clinical assessment laboratory.

PARTICIPANTS

Eighty amateur overhead athletes (mean [SD]: age = 23.03 [1.89]; weight = 78.36 [5.32]; height = 1.77 [.11]).

INTERVENTIONS

We randomly assigned participants to 4 research sub-groups in which they received the following treatments on their dominant shoulders: IASTM (n = 20), flossing (n = 20), both IASTM and flossing (n = 20), and kinesiology tape (n = 20). Nondominant shoulders served as controls.

MAIN OUTCOME MEASURE

We evaluated participants-before, immediately after, and 45 minutes after the therapeutic interventions-with the following tests: internal and external shoulder rotation range of motion, isokinetic strength and total work, the functional throwing performance index, and the one-arm seated shot put throw performance.

RESULTS

All therapeutic interventions significantly improved the strength and functional performance of the dominant shoulder in comparison with the control (P < .005) immediately after and 45 minutes after the treatment. The IASTM led to significantly greater improvement in shoulder internal rotation than kinesiology taping immediately after (P = .049) and 45 minutes after the treatment (P = .049). We observed no significant differences between the other treatment interventions (P > .05).

CONCLUSION

Findings from the current study support the use of novel soft tissue and neuromuscular techniques for the immediate and short-term improvement of the shoulder functional capacities in amateur overhead athletes.

DESCRIPTIVE PROFILE OF SHOULDER RANGE OF MOTION AND STRENGTH IN YOUTH ATHLETES PARTICIPATING IN OVERHEAD SPORTS

Background

The unilateral and repetitive nature of overhead sports, often result in a biomechanical overload of the upper extremity. Understanding the musculoskeletal shoulder range of motion (ROM) and strength patterns in the youth sports of baseball, softball, and tennis could assist injury prevention screening and further the development of conditioning and rehabilitation programs.

Purpose

To generate a descriptive profile of shoulder musculoskeletal characteristics and determine whether bilateral differences in shoulder ROM exist in youth baseball, softball, and tennis athletes. A secondary aim was to determine whether shoulder rotational adaptations are correlated with playing position, sport, or years of experience.

Study Design

Descriptive Laboratory.

Methods

A total of 136 competitive youth overhead athletes (baseball: n = 51,12.8 ± 0.9yrs; softball: n = 63,12.3 ± 1.1yrs; and tennis: n = 22,12.5 ± 0.9yrs) participated. Bilateral shoulder internal (IR) and external (ER) passive ROM and external rotation strength were measured using an inclinometer and handheld dynamometer.

Results

Significant differences (p<.001) in bilateral shoulder ROM and ER strength were found between the athletes in the three sports. Post-hoc test revealed tennis athletes had greater bilateral shoulder ROM than both baseball and softball athletes, but baseball and softball athletes had greater bilateral ER strength than tennis athletes. There were no differences between baseball and softball athletes. Additionally, tennis athletes had greater bilateral internal rotation and total ROM but less ER strength than baseball pitchers, baseball positional athletes, softball pitchers, and softball positional athletes. There were no significant differences between positions and baseball and softball athletes. There were no significant correlations between playing position, sport, or years of experience.

Conclusion

The results of this study showed differences in shoulder passive ROM and strength adaptations between youth tennis, baseball, and softball athletes. The descriptive nature of this study is impactful as it presents specific ROM adaptions seen in this population. Future research is needed to further evaluate if the "at risk" ROM identified in older populations holds true in the youth population.

Level of Evidence

Diagnosis, Level 3b.

Changes in clinical measures and tissue adaptations in collegiate swimmers across a competitive season

BACKGROUND

Competitive swimmers incur shoulder pain and injury. Physical characteristics such as shoulder range of motion (ROM) and endurance and tissue adaptations such as posterior capsule thickness (PCT) may be risk factors in addition to high training volume.

HYPOTHESIS/PURPOSE

1) To identify the most provocative special test and prevalence of positive special tests for shoulder impingement tests in a group of collegiate swimmers, (2) to assess shoulder pain and disability, internal rotation (IR) and external rotation, and horizontal adduction (HADD) ROM and posterior shoulder endurance longitudinally over a competitive collegiate season, and (3) determine if there is a relationship between swimming yardage, supraspinatus tendon organization, and PCT.

METHODS

Thirty Division III swimmers were tested poolside at the beginning (T1), middle (T2), and end (T3) of their season. Dependent variables included pain and disability, shoulder ROM, Posterior Shoulder Endurance Test (PSET) value, and PCT. Analyses of variance with follow-up t tests compared measures over time, and Pearson correlation coefficients were performed.

RESULTS

Despite increased swimming yardage, disability was reduced from T1 to T3 (P = .003). There was a reduction in bilateral IR and HADD ROM from T1 to T3. PSET values increased on the right from T1 to T3 (P = .014). There was a significant positive correlation between swimming yardage at T1 and T2 and PCT at T3 (P = .034, P = .028).

CONCLUSION

A loss of shoulder IR and HADD was observed across the season concurrent with less swimming-related disability, which may indicate a favorable adaptation. Improved PSET scores over the season is consistent with prior research linking endurance and less pain and disability.

The challenge of the sporting shoulder: From injury prevention through sport-specific rehabilitation toward return to play

Shoulder injuries and sports-related shoulder pain are substantial burdens for athletes performing a shoulder loading sport. The burden of shoulder problems in the athletic population highlights the need for prevention strategies, effective rehabilitation programs, and a individually based return-to-play (RTP) decision. The purpose of this clinical commentary is to discuss each of these 3 challenges in the sporting shoulder, to assist the professional in: (1) preventing injury; (2) providing evidence-based practice rehabilitation and; (3) to guide the athlete toward RTP. The challenges for injury prevention may be found in the search for (the interaction between) relevant risk factors, develop valid screening tests, and implement feasible injury prevention programmes with maximal adherence from the athletes. Combined analytical and functional testing seems mandatory screening an athlete's performance. Many questions arise when rehabilitating the overhead athlete, from exercise selection, over the value of stretching, toward kinetic chain implementation and progression to high performance training. Evidence-based practice should be driven by the available research, clinical expertise and the patient's expectations. Deciding when to return to sport after a shoulder injury is complex and multifactorial. The main concern in the RTP decision is to minimize the risk of re-injury. In the absence of a "gold standard", clinicians may rely on general guidelines, based on expert opinion, regarding cutoff values for normal range of motion, strength and function, with attention to risk tolerance and load management.