Elbow flexion and forearm supination strength in a healthy population

Strength after the arthroscopic Latarjet procedure: Are shoulder internal rotation, elbow flexion & supination strength decreased?

Background

The Latarjet procedure is an effective shoulder stabilizing surgery, however, the procedure results in an alteration of anatomy that may result in shoulder and elbow weakness. Thus, the purpose of this study was to assess post-operative shoulder and elbow strength after the Latarjet procedure. We hypothesized that shoulder and elbow strength are not affected after the procedure.

Methods

The study group consisted of patients that had undergone the arthroscopic Latarjet procedure. An isokinetic dynamometer was used to evaluate the strength of bilateral shoulder internal rotation, elbow flexion, forearm supination using peak torque (N/m), as well as grip strength (kilograms). Shoulder range of motion and the potential effects of hand dominance were further analysed.

Results

Nineteen patients with a mean age of 29 years and an average follow up of 47 months were included. Shoulder internal rotation strength, elbow flexion and forearm supination strength and grip strength were not significantly different when compared to the non-operative side (p > 0.13). The range of shoulder external rotation was significantly reduced (p < 0.001) on the Latarjet side.

Conclusion

The results from this study demonstrate no statistically significant differences in the strength of shoulder internal rotation, elbow flexion, forearm supination or grip strength despite the surgical alterations to the subscapularis and conjoint tendon.

The effect of handedness on upper extremity isometric strength symmetry

BACKGROUND

Understanding upper extremity strength symmetry can have important implications for ergonomics assessment and design. Few studies have examined isometric joint strength symmetry of left-handed individuals, or examined how handedness can influence strength. As such, the purpose of this study was to investigate the influence of handedness on dominant/non-dominant (D/ND) strength ratio in several moment directions about the shoulder, elbow, wrist, and hand. It was hypothesized that the isometric strength symmetry of left-handed individuals would be significantly different from that of right-handed individuals.

METHODS

The study recruited 28 participants to perform a series of maximal voluntary isometric contractions (MVCs) with both arms for various efforts about the shoulder, elbow, and wrist, as well as handgrip for a total of 68 MVCs. Strength symmetry ratios were computed, and a two-way mixed-model ANOVA evaluated the effects of handedness and MVC test on strength symmetry.

INTERPRETATION

Significant differences in D/ND ratios between right and left-handed individuals were found for 11 of the 17 explored exertion directions. Left-handed individuals tended to possess greater strength in their non-dominant limb, while right-handed individuals tended to have greater strength in their dominant limb. Left- and right-handed individuals often significantly differed in D/ND ratio, suggesting that separate normative values should be created to account for handedness when considering return-to-work or strength-based ergonomics design criterion.

Protocol for Forearm Pronosupination Strength Measuring in Different Postures: Reliability and Influence of Relevant Factors

IMPORTANCE

Despite the importance of pronosupination strength, which is key in daily activities, current evaluation protocols are disparate, and results differ regarding the influence of factors such as gender, age, limb dominance, or posture.

OBJECTIVE

To design a reliable device to measure pronation and supination torques in different forearm positions, considering the influence of gender, age, and limb dominance.

DESIGN

Reliability study with analysis of intrarater and interrater repeatability and examination of the influence of different factors on the strength of pronation and supination.

SETTING

Biomechanical analysis laboratory of the Instituto de Biomecánica de Valencia.

PARTICIPANTS

Convenience sample of 39 healthy male and female participants, ages 18 to 65 yr.

OUTCOMES AND MEASURES

Pronation strength and supination strength were studied in five forearm positions: 30° and 60° of supination, neutral rotation, and 30° and 60° of pronation. The influence of gender, age, and limb dominance was studied using repeated-measures analysis of variance. Intrarater and interrater reliabilities were studied in 17 participants, and the intraclass correlation coefficients (ICCs) were calculated from three measurement sessions.

RESULTS

Except for 60° of pronation, all ICCs ranged from .72 to .97. Gender, limb dominance, and posture significantly affected pronosupination strength (p < .05), with the highest supination strength at 60° of pronation and the highest pronation strength at 60° of supination.

CONCLUSIONS AND RELEVANCE

In using this reliable pronosupination torque assessment device and standardized protocol in the clinical setting, clinicians must consider the influence of gender, limb dominance, and forearm posture. What This Article Adds: The results of this study will allow occupational therapists to establish differences between patients' functionality in comparison with healthy individuals and to design recovery treatments and facilitate performance of manual tasks, considering which are the most advantageous positions to exert force. Furthermore, the developed device can be used to monitor the evolution of these torques in an objective and reliable manner.

Tenotomy or Tenodesis for Tendinopathy of the Long Head of the Biceps Brachii: An Updated Systematic Review and Meta-analysis

Purpose

The purpose of this meta-analysis was to provide an up-to-date comparison of clinical outcomes of tenotomy and tenodesis in the surgical treatment of long head of the biceps brachii (LHB) tendinopathy.

Methods

A literature search was conducted in EMBASE, Pubmed/Medline and the Cochrane database from January 2000 to May 2020. All studies comparing clinical outcomes between LHB tenotomy and tenodesis were included. Quality was assessed using the Coleman score.

Results

We included 25 studies (8 randomized studies) comprising 2,191 patients undergoing LHB tenotomy or tenodesis, with or without concomitant shoulder procedures (mainly rotator cuff repairs). The Coleman score ranged from 29 to 97 for all studies. When comparing tenodesis and tenotomy in randomized studies, no clinically relevant differences were found in the Constant score (mean difference, 0.9 points), the American Shoulder and Elbow Society Score (mean difference, 1.1 points), shoulder pain (mean difference in visual analogue scale, -0.3 points), elbow flexion strength loss (mean difference, 0%), or forearm supination strength (mean difference, 3%). A Popeye deformity (odds ratio, 0.32) was less commonly seen in patients treated with tenodesis (9% vs 23%).

Conclusion

In our meta-analysis, a Popeye deformity was more frequently observed in patients treated with tenotomy. Based on a substantial number of studies, there is no evidence-based benefit of LHB tenodesis over tenotomy in terms of shoulder function, shoulder pain or biceps-related strength. It is unclear whether LHB tenodesis is of benefit in specific patient groups such as younger individuals.

Level of evidence

Level III, systematic review of level III or higher studies.

Upper extremity strength: Normative reference data among uninjured employees

BACKGROUND

Extremity strength testing is used to determine the ability of industrial employees to perform a physically demanding occupation safely, evaluate post-injury impairment, and monitor return to function after injury. There is an unmet clinical need for a robust and granular source of normative reference values to serve as a resource for baseline data on upper extremity isometric strength.

OBJECTIVE

Develop normative reference data for upper extremity strength among industrial employees and investigate associations between strength and physical job demands.

METHODS

Upper extremity strength data from 107,102 industrial employees were collected post-hire. In this study, isometric tests for pinch; hand grip; wrist pronation and supination; and flexion of the wrist, elbow, and shoulder strength were retrospectively analyzed in relationship to sex, age, and job level. Associations between strength scores and five levels of work, defined the United States Department of Labor's Dictionary of Occupational Titles by level of physical difficulty (1-5), were determined.

RESULTS

Higher strength scores were positively associated with more physically demanding job levels (P < 0.001), and there was a progressive increase in strength scores with increased physical job demands for both sexes (P = 0.0002). All strength scores differed significantly by decade of age (P < 0.001). All scores except for pinch strength demonstrated a moderate or high positive correlation with job level (r≥0.50).

CONCLUSIONS

The normative reference upper extremity strength data collected in this study for industrial employees may be useful for evaluating rehabilitation and recovery following injury or illness. In order to utilize normalized strength data as a post-injury reference, it is important to consider job level in addition to age and sex, as these variables are highly correlated with baseline upper extremity strength.

Validation of a Practical Forearm Supination Strength Measurement Technique in the Large Sample Cohort

INTRODUCTION

The strength of forearm in pronation and supination (P/S) is an important clinical assessment during pre-operative examination as well as in post-operative evaluation. Many clinical trials concerning the measurement of forearm P/S strength were performed using a dynamometer fixed on the wall. The aim of this study was to bring out a simple and reliable technique for the measurement of P/S strength using a dynamometer manually supported and stabilized by an examiner. We hypothesized that there are no differences in evaluation of elbow P/S strength using the dynamometer fixed or the dynamometer stabilized by an operator in healthy people.

METHODS

The study was performed on a cross-sectional cohort of 100 healthy subjects without any history of injuries or previous surgery of the upper limbs. Isometric forearm P/S strengths were measured on the dominant and non-dominant forearms, using the dynamometer fixed on a table, and using the same dynamometer kept by an operator. The measurements were repeated in triplicate at 45°, 90° and 120° of elbow flexion in both upper limbs for all patients.

RESULTS

A total of 100 subjects (50 females, 50 males) were included in the study group. The mean age was 46.5 years (range 25-52 years). Female and male subjects showed no significant differences concerning the mean age (F/M ratio 0.50/0.50). The mean body mass index of all participants was 24.34 ± 3.66 kg/m2.No significant statistics difference was reported between the P/S strength measured using the two detection methods in our study group (45°, 90° and 120° of elbow flexion and both upper limbs).

CONCLUSION

The manually stabilized technique is a valid and reliable technique to assess the P/S strength of the forearm. This is a simple and effective method that may be reproduced in our daily clinical practice as well as in sportive practice.

Isokinetic evaluation of the shoulder and elbow after Latarjet procedure

BACKGROUND/HYPOTHESIS

The Latarjet procedure changes the anatomy of the shoulder, moving the coracoid process distally through an incision in the subscapularis muscle. Some authors have studied the effect of this surgery on shoulder rotator strength. Our hypothesis is that the Latarjet procedure decreases elbow supination and flexion strength.

METHODS

A retrospective case series, evaluating patients submitted to the Latarjet procedure between May 2013 and June 2017. Movements of the elbow (supination, pronation, flexion and extension) and shoulder (internal and external rotation) were evaluated bilaterally using a Biodex System 3 isokinetic dynamometer (Biodex Medical Systems, New York) in concentric/concentric mode.

RESULTS

We evaluated 20 patients with an average follow-up of 36 months. In the elbow, we observed a 9.1% decrease in supination strength at a speed of 60°/s (p=0.044), without statistical difference at 120°/s (p=0.570). In the shoulder, there was a 13.5% decrease in external rotation strength at 60°/s and 4.5% at 180°/s (p=0.009 and p=0.040, respectively). The other movements did not demonstrate any statistically significant differences.

CONCLUSION

After the Latarjet procedure, the supination strength at 60°/s was decreased, as was the external rotation strength of the shoulder at 60°/s and 180°/s. We did not observe any reduction in strength for shoulder flexion or internal shoulder rotation.

LEVEL OF EVIDENCE

IV, case series.

Biceps tenodesis versus tenotomy in isolated LHB lesions: a prospective randomized clinical trial

INTRODUCTION

Currently there exists no clear evidence concerning the surgical treatment of LHB lesions with either tenotomy or tenodesis. The aim of the study is therefore to evaluate elbow flexion and forearm supination force as well as the biceps muscle distalization according to both techniques in isolated LHB lesions.

METHODS

Consecutive patients aged 40-70 years with shoulder arthroscopies for isolated SLAP or biceps pulley lesions were prospectively randomized to arthroscopic suprapectoral intraosseous LHB tenodesis or tenotomy. Pre-, 6 and 12 months postoperatively, the SST, ASES, Constant-Murley and LHB scores were recorded. The elbow flexion force was measured in 10°/90° flexion, the supination force in neutral/pronation position. In addition, the maximum upper-arm circumference and its position relative to the radial epicondyle of the humerus were evaluated preoperatively and in follow-up.

RESULTS

20/22 patients (mean age 52.0 ± 8.5; range 36-63 years, 11 male) completed the follow-up. 9/20 were treated with LHB tenodesis (mean age 51.5 ± 9.5; range 37-63 years, 7 male) and 11/20 with tenotomy (mean age 52.8 ± 8.0; range 36-62 years, 4 male). The force measurements and scores showed no significant difference after 12 months. Tenodesis achieved a significant increase in force 6 months postoperatively compared to preoperatively. One tenodesis patient and three tenotomy patients showed a postoperative popeye-sign deformity.

CONCLUSION

This prospective randomized study comparing LHB tenodesis and tenotomy in isolated LHB lesions has shown no significant difference in elbow flexion and forearm supination force and clinical scores after 12 months. After LHB tenotomy, there was a non-significant trend for a higher rate of popeye-sign deformities of the upper arm and biceps muscle cramps.

Comparison of maximal isometric forearm supination torque in two elbow positions between subjects with and without limited forearm supination range of motion

Study Design: Cross-sectional comparison. Introduction: Forearm supination range of motion is often limited by short or stiff pronators. Many studies have examined maximal isometric forearm supination torque (MIFST). However, there is little research comparing MIFST in two elbow positions between subjects with and without limited forearm supination range of motion (LSR). Purpose of the Study: The purpose of this study was to compare MIFST in two elbow positions (90º flexed elbow, extended elbow) between subjects with and without LSR. Methods: Thirteen right-handed subjects (seven men, six women) with LSR and 13 age- and gender-matched healthy controls participated in this study. The forearm supination range of motion and MIFST were measured using a Smart KEMA system. Two-way repeated-measures analysis of variance was used to compare MIFST in two elbow positions between subjects with and without LSR. Results: No significant difference between groups (p > .05) was found. However, there was an interaction effect between elbow position and group on MIFST (p < .05). Independent t-tests were used to confirm the simple effects. In the LSR group, the value of MIFST was significantly lower in the elbow-extended position than in the group without LSR (p < .05). Conclusions: These findings indicate that elbow position should be considered when assessing the strength or increasing the strength of the supinator muscle, especially in patients with LSR.