Shoulder proprioception following reverse total shoulder arthroplasty

Shoulder Proprioception: A Review

The purpose of this review is to provide a comprehensive resource for shoulder proprioception assessment and its integration into clinical decision making as well as targeted rehabilitation protocols. Data for this review were acquired from peer-reviewed articles from computerized online databases, namely PubMed and Medline, published between 1906 and 2021. The development of digital/smart phone goniometers can improve shoulder joint range of motion (ROM) measurements and demonstrate comparable measurement accuracy to the universal standard goniometer. The inclinometer offers a portable and cost-effective method for measuring shoulder joint angles and arcs of motion in the vertical plane. Two types of dynamometers, the computerized isokinetic machine and the handheld hydraulic dynamometer, are reliable tools for objective shoulder rotator cuff strength assessment. Motion analysis systems are highly advanced modalities that create three-dimensional models of motion arcs using a series of cameras and reflective beads, offering unparalleled precision in shoulder proprioception measurement; however, they require time-consuming calibration and skilled operators. Advancements in wearable devices and compact mobile technology such as iPhone applications may make three-dimensional motion analysis more affordable and practical for outpatient settings in the future. The complex interplay between proprioception and shoulder dysfunction is not fully understood; however, shoulder proprioception can likely both contribute to and be caused by shoulder pathology. In patients with rotator cuff tears, glenohumeral osteoarthritis, and shoulder instability, clinicians can track proprioception to understand a patient's disease progression or response to treatment. Finally, rehabilitation programs targeting shoulder proprioception have shown promising initial results in restoring function and returning athletes to play.

Relationship between pain and proprioception among individuals with rotator cuff-related shoulder pain

BACKGROUND

Individuals with rotator cuff-related shoulder pain (RCRSP) have altered proprioception. The relationship between shoulder pain and proprioception is not well understood.

PURPOSE

This study aimed to investigate the relationship between shoulder pain and proprioception.

STUDY DESIGN

This was a cross-sectional comparative study.

METHODS

Twenty-two participants with RCRSP (mean age 27.6 ± 4.8 years) and 22 matched pain-free participants (23.4 ± 2.5 years) performed two upper limb active joint position sense tests: (1) the Upper Limb Proprioception Reaching Test (PRO-Reach; reaching toward seven targets) in centimeters and (2) Biodex System at 90% of maximum internal rotation in degrees. Participants performed three memorization and three reproduction trials blindfolded. The proprioception error (PE) is the difference between the memorized and estimation trials. Pain levels were captured pre- and post-evaluation (11-point Likert Numerical Pain Rating Scale). Relationships between PE and pain were investigated using independent t-tests and Spearman rank correlations.

RESULTS

Overall, 22.7% RCRSP participants indicated an increase in pain following the PRO-Reach (X̅ increase of 1.4 ± 1.5 points), while 59% did so with the Biodex (X̅ increase of 2.3 ± 1.8 points), reflecting a clinically important increase in pain. Weak-to-moderate correlations between pain and PEs were found with the Biodex (r = 0.39-0.53) and weak correlations with the PRO-Reach (r = -0.26 to 0.38). Concerning PEs, no significant differences were found between groups with the Biodex (p = 0.32, effect size d = -0.31 [-0.90 to 0.29]). The RCRSP participants demonstrated lower PEs with the PRO-Reach in elevation compared to pain-free participants (global X̅ = 4.6 ± 1.2 cm vs 5.5 ± 1.5 cm; superior 3.8 ± 2.1 cm vs 5.7 ± 2.9 cm; superior-lateral nondominant targets 4.3 ± 2.2 cm vs 6.1 ± 2.8 cm; p = 0.02-0.05, effect size d = 0.72-0.74 [0.12-1.3]).

CONCLUSIONS

Individuals with RCRSP demonstrated better upper limb proprioception in elevation, suggesting a change to interoception (sensory reweighting) in the presence of pain.

Measuring upper limb active joint position sense: Introducing a new clinical tool - The Upper Limb Proprioception Reaching Test

BACKGROUND

Proprioception is our sense of body awareness, including the sub-category of active joint position sense (AJPS). AJPS is fundamental to joint stability and movement coordination. Despite its importance, there remain few confident ways to measure upper limb AJPS in a clinic.

OBJECTIVE

To assess a new AJPS clinical tool, the Upper Limb Proprioception Reaching Test (PRO-Reach; seven targets), for discriminant validity, intra-rater and absolute reliability.

DESIGN

Cross-sectional measurement study.

METHODS

Seventy-five healthy participants took part in a single session with 2 consecutive evaluations (E1 and E2) (within-day reliability). Twenty participants were randomly selected to perform a dominant shoulder fatigue protocol (discriminant validity), whereafter a third evaluation was repeated (E3). The PRO-Reach was analyzed with paired t tests (discriminant validity), intra-class correlation coefficients (ICCs) and minimal detectable change [MDC]) (intra-rater: within-day and between-trial relative and absolute reliability).

RESULTS

The PRO-Reach supports moderate (mostly superior targets) to excellent (mostly inferior targets) reliability. Between-trial ICCs (T1/T2/T3) varied between 0.72 and 0.90, and within-day (E1/E2) ICCs between 0.45 and 0.72, with associated MDC95 values (3.9-5.0 cm). The overall scores (seven targets) supported the strongest within-day reliability (ICC = 0.77). The inferior targets demonstrated the highest between-trial and within-day reliability (ICCs = 0.90 and 0.72). A fatigue effect was found with the superior and superior-lateral targets (P < .05).

CONCLUSIONS

The inferior targets and overall scores demonstrate the strongest reliability. The use of the PRO-Reach tool may be suitable for clinical use upon further psychometric testing amongst pathological populations.

LEVEL OF EVIDENCE

Level III cross-sectional study.

Assessment of shoulder proprioception in patients with chronic mechanical cervical pain: A comparative study

BACKGROUND

Chronic mechanical cervical pain (CMCP) is a common disabling problem worldwide, interfering with upper extremities function. However studying the impact of CMCP on shoulder proprioception is still lacking.

OBJECTIVE

To investigate the impact of CMCP on shoulder proprioception in young adults compared with normal control (NC) individuals.

METHODS

A comparative study was conducted between two groups; 40 patients with CMCP (mean age 32.28 ± 6.586) and 40 age and sex matched NC (mean age 33.43 ± 9.021). The Biodex isokinetic dynamometer was used to assess shoulder active sense of position at 30∘ external and internal rotations. The absolute angular error was calculated for the dominant and non-dominant shoulders.

RESULTS

The absolute angular error was significantly increased only in the CMCP at both rotation angles for both shoulders, showing a remarkable increase on the dominant shoulder and in the external rotation range compared with NC.

CONCLUSIONS

CMCP can significantly impair shoulder proprioception, particularly on the dominant side and in external rotation range. This could emphasize the careful examination of shoulder proprioception for the early detection of shoulders at risk, to eliminate the possibility of shoulder instability and/or injury in young adults with CMCP.

Shoulder Proprioception Following Reverse Total Shoulder Arthroplasty for Unreconstructable Upper Third Fractures of the Humerus: 2-Year Outcomes

Background

Proximal humerus fractures may be comminuted in the elderly or after injury with high-energy mechanisms. Reverse total shoulder arthroplasty that may affect shoulder proprioception (rTSA) has also begun to play a part in treating acute proximal humeral fractures. In this study, the authors aimed to evaluate joint position sense (JPS) after rTSA.

Methods

Humac Norm II isokinetic device was used to evaluate the joint position sense. A joint angle was determined and the ability of the patient to create the same value of the angle by the active movement was evaluated. The difference between the pre-determined angle and the patient's measured angle was recorded. For proprioceptive sense, the initial position was 0° and the determination position was 30°, 60°, and 90° for flexion and abduction, and 15° and 30° for internal rotation and external rotation.

Results

While both the mean Constant and ADLEIR scores did not differ between non-operated and operated sides, the mean proprioception differences in all flexion (30°, 60°, and 90°), abduction (30°, 60°, and 90°), internal rotation (15° and 30°), and external rotation (15° and 30°) were significantly higher in the operated side than that in non-operated side (p < 0.01 for each pairwise comparison).

Conclusion

Reverse total shoulder arthroplasty (rTSA) treatment, which has increasingly become a surgical option in un-reconstructable proximal humeral fractures has significant adverse effects on proprioception on the operated side and may pose a risk for long-term instability, premature loosening, and prosthesis mechanical complications, in this context, well-designed prospective controlled studies are required.

Shoulder arthropathy secondary to syringomyelia: case series of 10 patients

PURPOSE

Neuroarthropathy is a progressive joint degeneration secondary to neurological diseases. In the upper extremity, the shoulder is the most exposed, and it is mainly caused by syringomyelia. This condition is rare; therefore, the literature has documented only a few case reports or case series of small groups of patients.

METHODS

We collected data about patients with shoulder arthropathy due to syringomyelia who were treated in our two institutes and collected among members of the Polish Shoulder and Elbow Society. Our analysis was based on epidemiological data, symptoms, and clinical examinations. We also examined the results of diagnostic tests, including-spinal cord MRI and shoulder X-ray, and treatment methods and their effectiveness.

RESULTS

The examined group included 10 women with an average age of 63 years. Of these, nine patients reported pain, seven reported-swelling, and nine reported-weakness. In every patient, diagnosis was confirmed by X-ray of the shoulder with joint degeneration and MRI of the spinal cord with syrinx. Two patients were operated with reverse shoulder arthroplasty; the first one had excellent result-significant active range of motion improvement and reduction of symptoms, and the second one had a good result-pain relief and moderate range of motion improvement. Other patients were conservatively treated, resulting in total or partial symptoms relief but without significant range of motion improvement.

CONCLUSION

Charcot shoulder secondary to syringomyelia was mainly manifested by range of motion limitation, swelling, and pain. Both conservative and surgical treatments could be a good solution. However, if reverse arthroplasty is technically possible, it seems to be the most promising treatment for recovering function.