Subacromial Anesthetics Increase Proprioceptive Deficit in the Shoulder and Elbow in Patients With Subacromial Impingement Syndrome

Shoulder Proprioception and Its Correlation with Pain Intensity and Functional Disability in Individuals with Subacromial Impingement Syndrome-A Cross-Sectional Study

Subacromial Impingement Syndrome (SAIS) is a common shoulder condition characterized by pain and functional impairment. Proprioception, the sense of joint position and movement, is crucial in maintaining joint stability and coordinating movements. The relationship between shoulder proprioception, pain intensity, and functional disability in individuals with SAIS remains unclear, with conflicting findings in the literature. This cross-sectional study aimed to evaluate shoulder proprioception, examine its correlation with pain intensity and functional disability, and contribute to our understanding of the clinical implications of proprioceptive deficits in individuals with SAIS. Forty-two individuals were diagnosed with SAIS, and an equal number of asymptomatic controls were recruited. Shoulder proprioception was assessed using a digital inclinometer, measuring joint position sense at various angles of flexion and rotation. Pain intensity was measured using the Visual Analog Scale (VAS), and functional disability was assessed using the Shoulder Pain and Disability Index (SPADI). Results: Individuals with SAIS exhibited significantly higher joint position error (JPE) values compared to asymptomatic controls in all measured angles of flexion and rotation (p < 0.001). Strong positive correlations were observed between JPE and pain intensity (r = 0.61 to 0.71, p < 0.01) and disability (r = 0.56 to 0.68, p < 0.01). These findings suggest impaired shoulder proprioception is associated with higher pain intensity and functional disability in SAIS. This study provides evidence of impaired shoulder proprioception in individuals with SAIS and its correlation with pain intensity and functional disability. The results highlight the clinical relevance of proprioceptive deficits in SAIS and emphasize the importance of incorporating proprioceptive assessment and targeted rehabilitation interventions into managing this condition. Future research should focus on longitudinal studies with larger and more diverse samples to further understand the underlying mechanisms and evaluate the effectiveness of proprioceptive interventions in improving outcomes for individuals with SAIS.

EFFICACY OF BALANCE TRAINING TO IMPROVE BALANCE OF YOUNG FEMALE GYMNASTS

Gymnastics is a popular sport that has potential strength, flexibility, and personal growth benefits for athletes. Both static and dynamic balance are developed from a young age and are fundamental to higher-level gymnastics. PURPOSE: To assess the efficacy of a balance training protocol in improving the dynamic balance of young female gymnasts. METHOD: 19 female Junior Olympic (JO) Level 3 gymnasts, ages 6-11, were randomly assigned to the Balance Training (BT) or control groups. The BT group completed a variety of balance exercises during each practice (2x/wk for eight weeks), including one-footed balance, hopping skills, and leaps onto surfaces of varying stability. Gymnasts in the control group continued with their normal gymnastics practices.  Gymnasts were tested before training, after week 4, and after week 8 to assess improvements in the Balance Error Scoring System (BESS), Star Excursion Balance Test (SEBT), Center of Pressure Path length (COP Path length), and Joint Position Sense (JPS) scores. RESULTS: An improvement in SEBT for the gymnasts’ dominant foot reaching anteriorly (p=0.03) was observed. Otherwise, there were no significant differences between improvements in scores for the control group and the experimental group. CONCLUSION: JO Level 3 gymnasts, who are early in their training and development, demonstrated no additional benefit from twice weekly balance training beyond normally prescribed practice and skills training.  While anecdotal evidence suggested a possible acute effect on balance performance immediately following balance exercises, further research is needed.

Effects of a Novel Proprioceptive Rehabilitation Device on Shoulder Joint Position Sense, Pain and Function

Background and Objectives: Shoulder disorders are associated with pain, restricted range of motion and muscular strength, moderate disability and diminished proprioception. This study aimed to compare the effectiveness of an innovative technology-supported and a classical therapist-based proprioceptive training program in addition to conventional physiotherapy, on joint position sense (JPS), pain and function, in individuals with different musculoskeletal shoulder disorders, such as rotator cuff tear, subacromial impingement syndrome and superior labrum anterior and posterior tear. The innovative element of the proprioceptive training programme consists of the use of the Kinesimeter, a device created for both training and assessing shoulder JPS. Materials and Methods: The shoulder JPS test and the DASH outcome questionnaire were applied to fifty-five individuals (28 females, 27 males, mean age 56.31 ± 6.75), divided into three groups: 17 in the conventional physiotherapy group (control group); 19 in the conventional physiotherapy + classical proprioceptive training program group (CPT group); and 19 in the conventional physiotherapy + innovative proprioceptive training program group (KPT group). Assessments were performed before and after a four-week rehabilitation program, with five physiotherapy sessions per week. Results: When baseline and post-intervention results were compared, the value of the shoulder JPS and DASH outcome questionnaire improved significantly for the KPT and CPT groups (all p < 0.001). Both KPT and CPT groups showed statistically significant improvements in JPS, pain and function, compared to the control group which received no proprioceptive training (all p < 0.05). However, the KPT group showed no significant benefits compared to the CPT group. Conclusions: Our findings indicate that using the Kinesimeter device as a novel, innovative proprioceptive training tool has similar effects as the classical proprioceptive training programs among individuals with different non-operated musculoskeletal shoulder disorders such as: rotator cuff tear, subacromial impingement syndrome, and superior labrum anterior and posterior tear.

Immunofluorescence analysis of sensory nerve endings in the periarticular tissue of the human elbow joint

INTRODUCTION

To investigate the dynamic aspects of elbow stability, we aimed to analyze sensory nerve endings in the ligaments and the capsule of elbow joints.

MATERIALS AND METHODS

The capsule with its anterior (AJC) and posterior (PJC) parts, the radial collateral ligament (RCL), the annular ligament (AL), and the ulnar collateral ligament with its posterior (PUCL), transverse (TUCL) and anterior parts (AUCL) were dissected from eleven human cadaver elbow joints. Sensory nerve endings were analyzed in two levels per specimen as total cell amount/ cm² after immunofluorescence staining with low-affinity neurotrophin receptor p75, protein gene product 9.5, S-100 protein and 4',6-Diamidin-2-phenylindol, Carbonic anhydrase II and choline acetyltransferase on an Apotome microscope according to Freeman and Wyke's classification.

RESULTS

Free nerve endings were the predominant mechanoreceptor in all seven structures followed by Ruffini, unclassifiable, Golgi-like, and Pacini corpuscles (p ≤ 0.00001, respectively). Free nerve endings were observed significant more often in the AJC than in the RCL (p < 0.00002). A higher density of Ruffini endings than Golgi-like endings was observed in the PJC (p = 0.004). The RCL contained significant more Ruffini endings than Pacini corpuscles (p = 0.004). Carbonic anhydrase II was significantly more frequently positively immunoreactive than choline acetyltransferase in all sensory nerve endings (p < 0.05). Sensory nerve endings were significant more often epifascicular distributed in all structures (p < 0.006, respectively) except for the AJC, which had a pronounced equal distribution (p < 0.00005).

CONCLUSION

The high density of free nerve endings in the joint capsule indicates that it has pronounced nociceptive functions. Joint position sense is mainly detected by the RCL, AUCL, PUCL, and the PJC. Proprioceptive control of the elbow joint is mainly monitored by the joint capsule and the UCL, respectively. However, the extreme range of motion is primarily controlled by the RCL mediated by Golgi-like endings.

Effects of Adding Aquatic-to-Land-Based Physiotherapy Programs for Shoulder Joint Position Sense Rehabilitation

There is limited evidence regarding the effects of aquatic-based physiotherapy on shoulder proprioception following post-traumatic injury to the joint. The main aim of this study was to investigate the effects of additional aquatic-based rehabilitation to a land-based physiotherapy program on shoulder joint position sense (JPS) rehabilitation. Forty-four individuals (mean age 44.50 ± 10.11) who had suffered a post-traumatic shoulder injury less than five months previously were pseudo-randomly allocated equally into a control group (9 females, 13 males) and experimental group (6 females, 16 males). Both groups received individualized standard land-based physiotherapy on average for 50 min per session, with five sessions per week for four consecutive weeks. The experimental group received an additional 30 min of personalized aquatic-based therapy during each session. Shoulder JPS was assessed by flexion (60°), extension (25°), abduction (60°), internal rotation (35°) and external rotation (35°) positions prior, halfway through, and after the intervention. Shoulder JPS improved significantly for all positions for both the control group (p < 0.03) and the experimental group (p < 0.01). No significant differences between the control group and the experimental group were found for change in shoulder JPS over time. Our results indicate that shoulder JPS can be significantly improved among individuals with post-traumatic injury to the joint through four weeks of personalized physiotherapy. The addition of aquatic-based exercises to standard land-based therapy did not, however, show significant benefits, and thus cannot be recommended for the improvement of shoulder JPS based on our findings.

Upper Limb Proprioceptive Acuity Assessment Based on Three-Dimensional Position Measurement Systems

The aim of the current work was to verify three-dimensional directional effects on the reproduction error precision of the human upper limb position. Thirty male subjects without history of upper limb pathology were recruited from Renmin University of China. A three-dimensional position reproduction task in six directions (up, down, left, right, far, and near) was performed by each subject. The results suggested that the proprioceptive sense of upper limb position depends on the direction, with smaller absolute errors in Directions 4 (right) and 5 (far) than in Directions 1 (up), 2 (down), 3 (left), and 6 (near). Proprioception near the end of the elbow joint range of motion may be more reliable and sensitive. Subjects reproduced fewer ranges in the horizontal plane (Directions 3, 5, and 6) and they overshot the target position along the z-axis (vertical direction) except for Direction 6. Overestimations of position in the z-axis may be caused by overestimations of force.

Effect of Force Level and Gender on Pinch Force Perception in Healthy Adults

This study investigated the effects of both force level and gender on pinch force reproduction errors in normal participants during an ipsilateral force reproduction task. In total, 20 healthy participants were asked to generate a range of levels of reference forces ranging from 5% to 60% maximal voluntary isometric contraction (MVIC) in increments of 5% MVIC using the tip pinch and to reproduce these forces using the same hand. The results showed that the males more accurately and consistently reproduced the forces than did the females, and the most accurate estimation occurred at approximately 20% to 35% MVIC. This finding can help us better understand the reasons for the higher rate of musculoskeletal disorders in females than in males and to develop tools and preventive strategies to decrease the rate of hand injuries in both genders.

Patients with Subacromial Pain Syndrome Present no Reduction of Shoulder Proprioception: A Matched Case-Control Study

BACKGROUND

Shoulder pain is common among patients with musculoskeletal pain and the prevalence of patients with subacromial pain syndrome (SAPS) is high. Despite the high prevalence, there is a lack of an extensive evaluation of the proprioception acuity in patients with SAPS. Knowledge of the proprioceptive deficit would assist clinicians in the proper treatment and may offer an alternative explanation for the mechanisms underlying SAPS, which are poorly understood.

OBJECTIVE

To compare the proprioceptive function of the shoulder in patients with SAPS and matched controls.

STUDY DESIGN

Matched case-control study.

SETTING

Physical Functional Rehabilitation Service of an outpatient clinic.

PARTICIPANTS

A total of 32 consecutive patients with SAPS who sought physical therapy for shoulder pain and 32 healthy participants (control group) matched for age, sex, and handedness.

INTERVENTIONS

All participants completed a questionnaire containing sociodemographic information, pain intensity and characteristics, the Numerical Pain Rating Scale, and the Shoulder Pain and Disability Index.

MAIN OUTCOME MEASUREMENTS

The proprioceptive assessment was performed through kinesthesia, passive joint position sense (PJPS), and the active joint position sense (AJPS).

RESULTS

The groups showed no statistically significant differences in kinesthesia, PJPS, and AJPS for internal or external rotation. The proprioceptive acuity was not associated with pain intensity or functional disability in patients with SAPS.

CONCLUSIONS

Participants with SAPS did not present proprioceptive deficits in a pain-free motion of medial and lateral rotation when compared to their matched controls. The proprioceptive deficit may not be involved with the mechanisms underlying SAPS and seems not to interfere with the clinical outcomes of patients with SAPS.

LEVEL OF EVIDENCE

Level III.

Patients with type 2 diabetes demonstrate proprioceptive deficit in the knee

AIM

To investigate proprioceptive discrepancies in the lower extremity in persons with type 2 diabetes mellitus (T2DM).

METHODS

In this cross-sectional study, a total of 46 older persons were divided into a T2DM group (n = 23) and a control group who did not have T2DM (n = 23). Participants were given a brief warm up with stretching exercises. Diabetic neuropathy scores were collected prior to proprioceptive testing. For proprioceptive testing, participants performed leg extensions to randomized target positions of 15°, 30°, 45, 60° degrees of elevation in the sagittal plane, each target was repeated a total of four times. Subjects were guided to target positions in the absence of visual feedback via auditory cues from a custom JPS application. When the participant entered the target position, they memorized the location of their limb in space and subsequently attempted to re-locate this position in space. Proprioceptive errors were measured from the target positioned, target remembered, target repositioned protocol.

RESULTS

Proprioceptive accuracy was lower in the diabetic group at all levels of target angle than the control group (P < 0.05). The diabetic group had 46% greater inaccuracy than the control group at all levels of target position. Diabetics also reported greater neuropathy scores than controls in the past 12 mo P < 0.01.

CONCLUSION

Deficits in lower limb localization and greater diabetic neuropathy scores were identified in this study. Our findings may be associated with deafferentation as peripheral neuropathy is a common complication with the disease. These findings may help to explain the declining balance function in the older persons with T2DM which is also commonly reported.