Focus: Vaccines: Shoulder Pain and Injury after COVID-19 Vaccination

Shoulder injury related to vaccine administration (SIRVA) is a term given to describe shoulder pain and dysfunction arising within 48 hours after vaccine administration and lasting for more than one week. While SIRVA is most commonly seen after influenza and tetanus vaccines, there have been a few recent case reports describing SIRVA-like symptoms after COVID-19 vaccine administration. Two patients presented to the shoulder surgeon’s practice center with complaints of shoulder stiffness and pain following the COVID-19 vaccine. The first patient was a 33-year-old man; he presented within 2 days of onset of the pain and 14 days from the vaccine date. He had a complete restriction of shoulder motion (0° flexion, and no external or internal rotation) at presentation. This patient was treated with non-steroidal anti-inflammatory drugs (NSAID) and rested in a sling for a week. The second patient was a 53-year-old woman; she presented with a 6-week duration of mild restriction of active shoulder motion and shoulder pain. Her magnetic resonance imaging (MRI) revealed the presence of subacromial-subdeltoid bursitis. She was treated with subacromial steroid injection and range of motion shoulder exercises. Both patients recovered a near-normal range of motion recovery within a month, and their pain improved significantly. The main lessons from this case report were: (1) patients presenting with a recent increase in pain and acute loss of shoulder movements after vaccination may be managed conservatively with rest and NSAID medications and (2) in case of a subacromial-subdeltoid bursitis in the MRI, subacromial injection of steroid may provide good pain relief.     

Active responses decrease impact forces at the hip and shoulder in falls to the side.

Active responses, such as using the arm to break the fall, may be an effective means of decreasing likelihood of injury in a fall and may help explain why only a small percentage of falls result in a fracture. We quantified the impact force at the hip and shoulder in falls to the side from a kneeling position under three conditions: (1) attempting to break the fall by using an arm; (2) falling with the body relaxed; and (3) falling with the body tensed. Subjects fell from a kneeling position onto a force platform array covered with foam padding and impact force data were recorded. The ground reaction force-time curve was generally bimodal due to sequential impacts of the hip and shoulder. Impact forces at the hip and shoulder were 12 and 16% less for the slap condition (p < 0.05) than for the tensed condition. The impact forces for the relaxed and tensed conditions were not significantly different, although impact forces tended to be less in the relaxed condition. We concluded that active responses reduce the impact forces experienced at the hip and shoulder in falls to the side. Decreased effectiveness of protective responses, due to increases in reaction time and decreases in strength with age, may help explain why so many hip fractures occur in the elderly but so few occur in younger people.     

Effects of age and sex on shoulder biomechanics and relative effort during functional tasks

Age-related decline in muscle strength can compromise shoulder function, which could increase the effort needed to perform activities of daily living (ADLs). The purpose of this cross-sectional study was to determine for the first time the relative shoulder effort during ADLs in healthy young and older adults.Ten healthy young adults and ten healthy older adults were tested for maximal isokinetic torque and on a set of ADL tasks. Using inverse dynamics, the shoulder torques during ADLs were referenced to the maximal isokinetic torque and relative effort was determined.Older compared to younger adults had >40% lower isokinetic shoulder abduction strength. The ratio of peak joint torque during six ADLs over the maximal isokinetic torque, i.e., relative effort, was higher in old (∼52%) compared with young adults (∼22%, p < 0.05). Relative effort in older adults was over 40% in overhead activities and particularly high in abduction and reaching tasks, over 60%.Healthy older compared with younger adults perform most ADL tasks involving the shoulder joint with nearly twice the level of relative effort. The concomitant reductions in maximal shoulder isokinetic torque and increases in relative effort may be related to the high prevalence of musculoskeletal pain and shoulder dysfunction in old age reported in epidemiological studies.     

Adaptation of scapula lateral rotation after reverse anatomy shoulder replacement

Scapula motion is significant for support of the arm and stability of the shoulder. The effect of the humeral elevation on scapular kinematics has been well investigated for normal subjects, but there are limited published studies investigating adaptations after shoulder arthroplasty. Scapula kinematics was measured on 10 shoulders (eight subjects) with a reverse total joint replacement. The measurements were performed using an instrumented palpating technique. Every subject performed three simple tasks: abduction, elevation in scapula plane and forward flexion. Results indicate that, lateral scapula rotation was significantly increased (average of 24.42% over the normal rhythm) but the change was variable. Despite the variability, there is a clear trend correlating humeral performance with increased rotation (R2 0.829). There is clearly an adaptation in lateral scapula rotation in patients with shoulder joint replacement. The reason for this is unclear and may be related to joint pathology or to muscle adaptation following arthroplasty.     

Evolution of the turtle bauplan: the topological relationship of the scapula relative to the ribcage

The turtle shell and the relationship of the shoulder girdle inside or ‘deep’ to the ribcage have puzzled neontologists and developmental biologists for more than a century. Recent developmental and fossil data indicate that the shoulder girdle indeed lies inside the shell, but anterior to the ribcage. Developmental biologists compare this orientation to that found in the model organisms mice and chickens, whose scapula lies laterally on top of the ribcage. We analyse the topological relationship of the shoulder girdle relative to the ribcage within a broader phylogenetic context and determine that the condition found in turtles is also found in amphibians, monotreme mammals and lepidosaurs. A vertical scapula anterior to the thoracic ribcage is therefore inferred to be the basal amniote condition and indicates that the condition found in therian mammals and archosaurs (which includes both developmental model organisms: chickens and mice) is derived and not appropriate for studying the developmental origin of the turtle shell. Instead, among amniotes, either monotreme mammals or lepidosaurs should be used.     

Axillary artery injury combined with delayed brachial plexus palsy due to compressive hematoma in a young patient: a case report

Aim

To prove the possibility of axillary nerve conduction changes following shoulder subluxation due to hemiplegia, in order to investigate the usefulness of screening nerve conduction studies in patients with hemiplegia for finding peripheral neuropathy.

Methods

Forty-four shoulders of twenty-two patients with a first-time stroke having flaccid hemiplegia were tested, 43 ± 12 days after stroke onset. Wasting and weakness of the deltoid were present in the involved side. Motor nerve conduction latency and compound muscle action potential (CMAP) amplitude were measured along the axillary nerve, comparing the paralyzed to the sound shoulder. The stimulation was done at the Erb's point whilst the recording needle electrode was inserted into the deltoid muscle 4 cm directly beneath the lateral border of the acromion. Wilcoxon signed rank test was used to compare the motor conduction between the sound and the paralytic shoulder. Mann-Whitney test was used to compare between plegic and sound shoulder in each side.

Results

Mean motor nerve conduction latency time to the deltoid muscle was 8.49, SD 4.36 ms in the paralyzed shoulder and 5.17, SD 1.35 ms in the sound shoulder (p < 0.001). Mean compound muscle action potential (CMAP) amplitude was 2.83, SD 2.50 mV in the paralyzed shoulder and was 7.44, SD 5.47 mV in the sound shoulder (p < 0.001). Patients with right paralyzed shoulder compared to patients with right sound shoulder (p < 0.001, 1-sided for latency; p = 0.003, 1-sided for amplitude), and patients with left paralyzed shoulder compared to patients with left sound shoulder (p = 0.011, 1-sided for latency, p = 0.001, 1-sided for amplitude), support the same outcomes. The electro-physiological changes in the axillary nerve may appear during the first six weeks after stroke breakout.

Conclusion

Continuous traction of the axillary nerve, as in hypotonic shoulder, may affect the electro-physiological properties of the nerve. It most probably results from subluxation of the head of the humerus, causing demyelinization and even axonopathy. Slowing of the conduction velocities of the axillary nerve in the paralyzed shoulders may be related also to the lowering of the skin temperature and muscular atrophy in the same limb. The usefulness of routine screening nerve conduction studies in the shoulder of hemiplegic patients seems to be advocated.     

Shoulder complex kinematics pre- and post- rotator cuff repair

This study investigated shoulder complex joint kinematics and functional outcomes before and after full-thickness supraspinatus rotator cuff repair. Nine adults (mean age 63.4 ± 6.2 years) participated in three test sessions: 0–12 weeks pre-operatively, 9–12 weeks, and 22–30 weeks post-operatively. Upper extremity kinematics of the surgical arm’s glenohumeral, acromioclavicular, sternoclavicular and thoracohumeral joints over the duration of a hair combing task were quantified with motion analysis using inverse kinematics. The UCLA Shoulder Rating and Simple Shoulder Test shoulder health outcomes were administered at each session to determine patients’ perceived function of their surgical shoulder. Results indicated multiple significant increases over time among the three joints comprising the shoulder complex in the coronal and transverse planes, despite no increases in thoracohumeral motion, and suggest that thoracohumeral motion alone does not provide a comprehensive assessment. Interestingly, more significant increases were observed at the 6-month evaluation than the 3-month evaluation, which is not aligned with the standard rehabilitation endpoint. Thus, our findings suggest that clinicians should evaluate all joints of the shoulder complex during longer-term rehabilitation assessment. Ultimately, knowledge of patients’ pre-operative and post-operative shoulder complex kinematics may help to improve rehabilitation to promote improved patient outcomes.     

The effect of prolonged isometric contractions on muscle fluid balance

Ultrasound scanning was performed at three sites above the fossa supraspinata on nine healthy subjects and five patients with myofascial shoulder pain. This method produced a well-defined depiction of the soft tissue layers above the fossa supraspinata and reproducible muscle thickness measurements. In the healthy subjects the average distance from the skin surface to the trapezius muscle was 7.7 mm and the average thickness of the trapezius muscle was 5.3 mm, and the average thickness of supraspinatus muscle was 20.0 mm. The supraspinatus muscle was thinner at the medial measuring site than at the other two sites. In contrast, a tendency towards a larger distance was seen from the skin to trapezius muscle at the medial measuring site than at the other two sites. No statistical differences were found between the two groups of subjects either at rest or during brief shoulder abductions. All the subjects performed a 30° unilateral isometric shoulder abduction test to exhaustion. The median endurance time was 33 min for the healthy subjects and only 5 min for the patients. The ratings of perceived exertion (RPE) were in line with this, since the increment in RPE with time was larger for the patients than for the healthy group. The reduced shoulder abduction endurance time in the patient group may have been related to impaired muscle function and/or pain development. During the 33-min shoulder abduction in the healthy subjects, the thickness of supraspinatus muscle increased by 14%, indicating muscle swelling, whereas the thickness of trapezius muscle remained constant. The fluid imbalance in the supraspinatus muscle compartment may well play a role in the development of muscle fatigue and the disorders found in industry resulting from prolonged work with arms elevated.     

No Correlation Between Three Selected Trade‐Offs in Birdsong Performance and Male Quality for a Species With Song Repertoires

Demanding performance of vocal signals, such as birdsong, may be evaluated by trade‐offs among acoustic traits. If individuals differ in their ability to sustain physiologically demanding singing, then aspects of song performance resulting from such trade‐offs could signal individual quality. Song performance can also differ among song types, and it is not known whether this influences the assessment of individual quality. We asked whether three trade‐off‐based measures of song performance indicate male age or aspects of condition (body condition, hematocrit and ectoparasite load) in the dark‐eyed junco (Junco hyemalis), a species with small repertoires. Across a sample of over 100 males, no measure of song performance was related to male age or condition, nor did song performance improve with age for those males recorded in consecutive years. In all cases, the variation in song performance explained by these predictors was small (<4%). Instead, the more song types we recorded from a male, the more likely we were to record high‐performance songs, and this sampling effect was stronger than putative correlations with male quality. These results complement a previous study on this population showing that most variation in performance is found among song types rather than among males. Collectively, the lack of association between trade‐off‐based aspects of song performance and male age or condition, plus variation among song types that interferes with rapid assessment of a male's best performance, indicate that these aspects of song performance do not allow a good assessment of male quality in juncos, and perhaps more generally in species with song repertoires.     

The effect of tactile and verbal guidance during scapulothoracic exercises: An EMG and kinematic investigation

BackgroundClinician-led training through tactile and verbal guidance to improve muscle activity and joint motion are a common but understudied focus of therapeutic interventions for shoulder pain. The purpose of this study was to determine if clinician guidance changes scapulothoracic muscle activity and kinematics compared to unguided shoulder exercises.MethodsEleven participants with shoulder pain were studied. Electromyographic (EMG) sensors were placed on the serratus anterior and upper and lower trapezii. Scapulothoracic and sternoclavicular kinematics were collected using electromagnetic sensors. Five common resisted shoulder exercises were performed with the following guidance: unguided, combined (verbal and tactile cues), and verbal guidance only. One-way repeated measures ANOVAs determined the effect of guidance versus unguided conditions for each exercise.ResultsNine of ten combinations of exercise and guidance techniques demonstrated a significant effect of guidance for either muscle activity or joint kinematics. The guidance condition with the most frequent significant improvements across all variables was the combined condition. The exercises with the most frequent significant improvements across all variables were the external rotation exercises. Variables improved most frequently were: upper:lower trapezius EMG ratio (up to 11%), sternoclavicular elevation (up to 6°) and scapulothoracic internal rotation positioning (up to 8°), and sternoclavicular retraction displacement (up to 5°).ConclusionShoulder muscle activity and kinematics during exercises can be modified by tactile and verbal guidance. Most improvements in muscle activity occurred with verbal guidance during external rotation exercises. Most improvements in joint positioning and movement occurred with combined guidance during external rotation exercises.     

Muscle activation in the contralateral passive shoulder during isometric shoulder abduction in patients with unilateral shoulder pain.

Studies have shown an increased muscle activation at the opposite passive side during unilateral contractions. The purpose of the present study was to examine the influence of pain on muscle activation in the passive shoulder during unilateral shoulder abduction. Ten patients with unilateral rotator tendinosis of the shoulder and nine healthy controls performed unilateral maximal voluntary contractions (MVC) and sustained submaximal contractions with and without subacromial injections of local anaesthetics of the afflicted shoulder. Muscle activation was recorded by electromyography (EMG) from the trapezius, deltoid, infraspinatus and supraspinatus muscles in both shoulders. During MVCs, the EMG amplitude from muscles of the passive afflicted side was not different in patients and controls, and was not influenced by pain alterations. In contrast, the EMG amplitude from the muscles of the passive unafflicted side was lower in the patients and increased after pain reduction. During the sustained submaximal contraction the EMG amplitude increased gradually in the passive shoulder to 15-30% of the EMG amplitude observed during MVC. This response was not influenced by differences in pain. We conclude that muscle activation of the passive shoulder was closely related to the activation of the contracting muscles and thus related to central motor drive, and not directly influenced by changes in pain.     

Malalignment of the shoulder after stroke.

One hundred and ten consecutive patients (51 men, 59 women) admitted to a stroke unit were studied for radiographic changes at the shoulder on the affected side. Malalignment was found in 51 (46%) patients, of whom 37 (72.5%) had changes on the initial x-ray film and a further 14 (27.5) developed malalignment over the following 12 months. These findings indicate that malalignment of the shoulder is common in the early stages of a stroke and may be missed unless radiographs are taken with the patient erect and the arm unsupported. Malalignment may lead to delay and limitation in restoration of function. The consequences of malalignment can be prevented by correct handling, positioning, and full passive movement of the shoulder from the onset of the stroke.     

Physical and psychosocial symptoms among 88 volunteer subjects compared with patients seeking plastic surgery procedures to the breast

In an investigation of the relationship between macromastia and physical and psychosocial symptoms, 88 female university students, 21 augmentation mammaplasty patients, and 31 breast reduction patients graded somatic and psychosocial symptoms. The intent of the study was to discover which complaints were most common among women presenting for reduction mammaplasty and to determine whether height/weight index and brassiere chest measurement and cup size might affect their symptoms. Both the student group and the augmentation mammaplasty patients differed significantly from the breast reduction patients. Eighty-one percent of the reduction patients complained of neck and back pain. Seventy-seven percent complained of shoulder pain, 58 percent complained of chafing or rash; 45 percent reported significant limitation in their activity; and 52 percent were unhappy with their appearance (p < 0.001 compared with augmentation and student groups). Physical symptoms were related to height/weight index and bra chest and cup sizes in each of the three participating groups. It was found that patients who present for symptom-related reduction mammaplasty have a disease-specific group of physical and psychosocial complaints that are more directly related to large breast size than to being overweight.     

Significance of shoulder function in the reconstruction of prehension with double free-muscle transfer after complete paralysis of the brachial plexus

Reconstruction of shoulder stability and movement in cases with complete paralysis of the brachial plexus was performed to improve the outcomes for universal function of prehension after double free-muscle transfer (Doi's procedure). In cases in which the C5 or C6 nerve root was available as a donor, neurotization of the supra-scapular nerve was performed with a nerve graft. If the C5 or C6 nerve root was not available, then the contralateral C7 nerve root was chosen as the donor motor nerve and was transferred to the suprascapular nerve by using a vascularized ulnar nerve graft. Seven cases with ipsilateral C4, C5, or C6 nerve root transfer to the suprascapular nerve and one with contralateral C7 transfer were evaluated, and the functional outcomes for the range of shoulder motion were compared with those for patients who had undergone arthrodesis of the humeroscapular joint or had undergone no procedures for shoulder function reconstruction. The patients who underwent supra-scapular nerve repair demonstrated statistically significantly better ranges of motion for flexion and abduction of the shoulder, compared with the other two groups. Shoulder function is important for achieving prehensile function among patients with complete paralysis of brachial function, when they undergo double free-muscle transfer.     

Scapula alata in early breast cancer patients enrolled in a randomized clinical trial of post-surgery short-course image-guided radiotherapy

ABSTRACT: BACKGROUND: Scapula alata (SA) is a known complication of breast surgery associated with palsy of serratus anterior, but is seldom mentioned. We evaluated the risk factors associated with SA and the relationship of SA with ipsilateral shoulder/arm morbidity in a series of patients enrolled in a trial of post-surgery radiotherapy (RT). METHODS: The trial randomized women with completely resected stage I-II breast cancer to short-course image guided RT, vs. conventional RT. SA, arm volume and shoulder-arm mobility were measured prior to RT and at 1-3 months post-RT. Shoulder/arm morbidities were computed as post-RT percent change relatively to pre-RT measurements. RESULTS: Of 119 evaluable patients, 13 (=10.9%) had pre-RT SA. Age younger than 50 years old, body mass index less than 25 kg/m2, and axillary lymph node dissection, with odds ratios of 4.8 (P=0.009), 6.1 (P=0.016), and 6.1 (P=0.005), respectively. Randomization group was not significant. At 1-3 months post-RT, mean arm volume increased by 4.1% (P=0.036) and abduction decreased by 8.6% (P=0.046) among SA patients, but not among non SA patients. SA resolved in 8, persisted in 5, and appeared in 1 patient. CONCLUSION: Relationship of SA with lower body mass index suggests that SA might have been underestimated in overweight patients. Despite apparent resolution of SA in most patients, pre-RT SA portended an increased risk of shoulder/arm morbidity. We argue that SA warrants further investigation. Incidentally, the observation of SA occurring after RT in one patient represents the second case of post-RT SA reported in the literature.     

Metabolomic approaches to mitochondrial disease: correlation of urine organic acids

In order to examine correlations which might be useful in ascertaining or confirming the diagnosis of mitochondrial disease, a retrospective analysis of urine organic acids was performed. Among 3646 analyses from randomly selected samples referred to our laboratory, there were 258 specimens from 67 patients with various known disorders of mitochondrial oxidative function, most of whom were known to have chronic and persistent elevations of blood lactic acid, and 176 samples from 21 patients with diagnosed organic acidemia. Urine lactate was not a useful discriminator; only 7.6% of results from infants with mitochondrial disease fell the 95th percentile for patients without mitochondrial disease. Most of the Krebs cycle intermediates were also not useful in discriminating patients with mitochondrial disorders. Interestingly, there was strikingly poor correlation among most of those analytes in all patient groups, but fumarate and malate were uniquely well correlated (r2 = 0.840). Fumarate and malate were also the most useful in distinguishing patients with mitochondrial disease and organic acidemia from the pool of unselected or undiagnosed patients, although the utility was somewhat limited. Using a cutoff value of approximately 90 mmol/mol creatinine for fumarate or malate at age <1 year, or a cutoff of approximately 25 for older patients, 25ndash; 30% of mitochondrial disease patients can be distinguished with a 5% false positive rate. Further refinements to this approach may better characterize the metabolomic profile and may improve the diagnostic utility of quantitative organic acid analysis in mitochondrial disease.     

Lymphoma with hypercalcemia

A prospective survey was carried out to determine the incidence of hypercalcemia in hospitalized patients with lymphoma. Serum calcium determinations were carried out during 440 admissions on 152 patients, most of whom had widespread lymphoma. Forty-one of the 152 patients died, all having had calcium levels recorded on that admission. Two of the 152 patients (1.3%) were found to have hypercalcemia. By comparison hypercalcemia occurred in 6 of 34 patients (17.6%) with multiple myeloma.Hypercalcemia is uncommonly associated with lymphoma but may be seen particularly in centres where many patients with this disease are treated. Hypercalcemia readily responds to therapy and is a reversible cause of morbidity, but when associated with lymphoma it usually indicates widespread disease. The mechanism of hypercalcemia is unknown but there is strong evidence for humoral factors that may or may not be related to parathyroid hormone.     

Assessment of biomechanical parameters of the shoulder joint at the operated side versus non-operated side in patients treated surgically for breast cancer

Aim

Isokinetic assessment of biomechanical parameters of the shoulder joint at the operated side versus non-operated side in patients treated surgically for breast cancer according to the type of surgery performed.

Comparison of physiotherapy,manipulation, and corticosteroid injection for treating shoulder complaints in general practice: randomised,single blind study.

OBJECTIVE: To compare the efficacy of physiotherapy, manipulation, and corticosteroid injection for treating patients with shoulder complaints in general practice. DESIGN: Randomised, single blind study. SETTING: Seven general practices in the Netherlands. SUBJECTS: 198 patients with shoulder complaints, of whom 172 were divided, on the basis of physical examination, into two diagnostic groups: a shoulder girdle group (n = 58) and a synovial group (n = 114). INTERVENTIONS: Patients in the shoulder girdle group were randomised to manipulation or physiotherapy, and patients in the synovial group were randomised to corticosteroid injection, manipulation, or physiotherapy. MAIN OUTCOME MEASURES: Duration of shoulder complaints analysed by survival analysis. RESULTS: In the shoulder girdle group duration of complaints was significantly shorter after manipulation compared with physiotherapy (P < 0.001). Also the number of patients reporting treatment failure was less with manipulation. In the synovial group duration of complaints was shortest after corticosteroid injection compared with manipulation and physiotherapy (P < 0.001). Drop out due to treatment failure was low in the injection group (17%) and high in the manipulation group (59%) and physiotherapy group (51%). CONCLUSIONS: For treating shoulder girdle disorders, manipulation seems to be the preferred treatment. For the synovial disorders, corticosteroid injection seems the best treatment.