Shoulder Instability – Causes, Symptoms, Diagnosis, Treatment

Shoulder Instability

Shoulder Instability may be caused due to a traumatic mechanism that are almost always accompanied by moderate to severe soft tissue injury, proximal humerus fractures, avulsion fractures of the greater tuberosity, fractures of the acromion, clavicle, coracoid process, or glenoid rim, and rotator cuff tears. Rotator cuff and greater tuberosity fractures

The shoulder is a complex, mobile, multiaxial, ball-and-socket articulation that allows coordinated motion in the frontal, transverse, and sagittal planes.  The latter may allow for 360 degrees of circumduction.  The relatively shallow glenoid fossa articulates with the much larger humeral head to allow for a wide range of physiologic motion. Also, the joint capsule is relatively laxative and shoulder movements occur secondary to the dynamic and coordinated articulations at four distinct joints

  • Sternoclavicular
  • Acromioclavicular
  • Glenohumeral
  • Scapulothoracic

Types of Shoulder Instability

The types of shoulder instability are following 

  • Static instability – Static stability includes the glenohumeral articulation, labrum, the glenohumeral joints ligaments, rotator cuff muscle structures, and the negative intra-articular pressure.
  • Dynamic instability – The dynamic stability consists of the rotator cuff muscles, the deltoid muscle, and the scapular and periscapular muscle stability. However, shoulder instability is a pathologic process that results in an excessive movement of the humeral head on the glenoid fossa that ultimately results in pain, weakness, and shoulder dysfunction.
  • Unidirectional Instability – Unidirectional instability can be caused by following acute trauma or following one or multiple low-energy instabilities injuries. The latter may be present in the setting of unidirectional or bidirectional instability with or without hyperlaxity. In effect, the unidirectional instability is often attributable to the patulous capsular tissue that is a reason of the shoulder to recurrent instability events. However, the same unidirectional instability will present with an associated capsulolabral injury.
  • Humeral Sided Defects Instability – The Hill-Sachs lesion is an impaction injury to the posterosuperolateral humeral head that occurs in association with anterior instability.   The Hill-Sachs lesion occurs when the humeral head dislocates anteroinferior position of the humeral head abuts the anterior glenoid rim.
  • Glenoid Sided Defects Instability – The prevalence of glenoid bone loss is also not consistently reported in all cases although most scientists and doctors agree that in the setting of recurrent instability, there will inevitably be some degree of glenoid bone loss. Some studies have indicated that up to 22% of patients will present with some degree of glenoid deficiency after an initial dislocation event, that increasing to 25% to 90% of patients presenting with recurrent instability, and in 90% of patients presenting status, post failed primary stabilization procedures.
  • Multidirectional Instability – Since the initial description of multidirectional shoulder instability (MDI), our knowledge regarding the pathologic findings and objective criteria for diagnosing MDI remains debated. The part of the clinical symptoms is attributable to the lack of a precise definition for MDI.  Neer and Foster initially described MDI as anterior and posterior instability associated with involuntary inferior subluxation or dislocation of the shoulder joints.
  • Recurrent Instability – Recurrent instability can develop in the setting of any of the above-mentioned underlying pathophysiologic mechanisms and its abnormality. Furthermore, recurrent instability can present following a nonoperative and operative management system.

Grade of Shoulder Instability

The grade of shoulder instability is following 

Burkhart and colleagues in 2014 proposed an algorithmic approach that is mentioned below.  The treatment paradigm broke shoulder instability and dislocations cases into four subgroups to help guide the surgical technique most appropriate to employ:

  • Group 1 shoulder instability patients position

    • Glenoid: less than 25% of defect may present
    • Hill-Sachs if present: On track lesion, or non-engaging lesion may be found
    • Technique: Arthroscopic Bankart repair is very helpful
  • Group 2 shoulder instability patients

    • Glenoid: less than 25% of defect may present
    • Hill-Sachs: Off-track lesion or engaging lesion may be found
    • Technique: Arthroscopic Bankart repair plus remplissage
  • Group 3 shoulder instability patients

    • Glenoid: greater than 25% defect
    • Hill-Sachs: On track lesion, or non-engaging lesion
    • Technique: Latarjet procedure
  • Group 4 shoulder instability patients
    • Glenoid: greater than 25% defect
    • Hill-Sachs: It is an Off-track lesion or engaging lesion
    • Technique: Latarjet procedure with or without a humeral-sided procedure
      • The glenoid fossa is addressed firstly, and following the glenoid augmentation procedure, the further characterization of the Hill-Sachs lesion.
      • If the Hill-Sachs lesion is engaging or off track, then humeral-sided procedures are recommended.
      • Remplissage procedure
      • Humeral bone grafting techniques

Causes of Shoulder Instability

The Causes of shoulder instability are following 

  • The acromioclavicular joint injury that also causes shoulder instability
  • Bicipital tendonitis injury
  • Road Traffic injury
  • Clavicle fractures in acute or chronic injury
  • Rotator cuff muscle injury may also cause a shoulder instability
  • Shoulder subluxation also causes shoulder instability
  • Fall from height
  • Swimmer’s shoulder joints injury most often causes shoulder instability
  • Traumatic injury, unilateral or by lateral, bankart lesion in most commonly, surgical abnormal.
  • Atraumatic injury, multidirectional movement injury, bilateral disorder,
  • Proper or lack of rehabilitation timely also causes shoulder instability,
  • Inferior capsular shift injury also causes shoulder instability
  • Unilateral- or multi-directional instability injury
  • Atraumatic injury cases are often multidirectional with the associated hyperlaxity problems.
  • Traumatic injury in most cases is often unidirectional injury with an associated capsulolabral injury in the shoulder joint.
  • Lake of presence or absence of accompanying soft-tissue hyperlaxity problem may also cause a shoulder instability
  • In most cases of soft tissue hyperlaxity, including patulous capsular laxity injury in shoulder instability
  • It can be congenital or secondary to repeated micro traumatic injury also causes shoulder instability,
  • The major trauma, multiple instability events problem, recurrences, or a combination of all of these factors.
  • An acute, low-energy, compression fracture in most cases.
  • Chronic or recurrent, low-energy, attritional deficiency, and erosive changes can be over time.
  • Suprascapular nerve entrapment injury also causes shoulder dislocation
  • Quadrilateral space syndrome may lead to shoulder dislocation
  • Posterior glenoid spur (Bennett lesion) also causes shoulder dislocation
  • Early osteoarthritis
  • Tumor

Symptoms of Shoulder Instability

The symptoms of shoulder instability are following 

  • The first symptom of shoulder instability is pain and progressive stiffness, limited range of motion, fibrous tissue formation,
  • Restriction of movement in the glenohumeral joint capsule, ligaments, tendons, and muscle may also cause a shoulder instability
  • The second symptom of pain that also causes shoulder instability is impossible to get dressed up and out, cooking, clean, reach a back pocket, or shift gears while driving a car, putting the arm up and back.
  • Fractures of the tuberosity, surgical neck fractures may occur in most cases and should not be reduced in the emergency department in the acute stage
  • Bankart lesion is one of the most common problems that may develop when the glenoid labrum is disrupted with or without the addition of an avulsed bone fragment bony Bankart.
  • The soft Bankart lesions involving in most cases and the inferior anterior labrum are more common that lead to aggressive pain, swelling, tenderness.
  • The Hill-Sachs deformity is a compression fracture of the posterolateral humeral joints and head primarily with anterior dislocations disorders are found
  • A feeling of pain and tightness in the whole shoulder area causes pain for shoulder instability
  • A feeling of tightness especially when you are throwing a ball overarm in cricket-playing, golf.
  • Decrease range of motion is lost in the following direction such as external rotation, abduction, internal rotation, forward flexion.
  • Pain on the back and decrease the range of motion.
  • Dull, aching pain with paresthesia, itching, numbness
  • The referred pain and may felt in whole shoulder joints to the arms, forearms
  • The sleep disturbance and the problem with deprivation
  • Severe sharp pain and with rapid movement (eg. trying to catch mobile phone)
  • The difficulty with activities of daily living such as dressing, driving, and personal care.
  • Lack of movement in all directions of your hand
  • Symptoms will worsen at night and morning stiffness may be felt.
  • Muscle contraction of the coracohumeral ligament limits external rotation of the arm and forearms
  • Muscle contracture and tendinopathy and capsulitis may be felt.
  • Dull” or “deep-seated pain in the rotator cuff muscle and spread into the biceps muscles.
  • The Reverse Hill-Sachs lesions fractures most commonly seen in posterior shoulder instability disorders are also called a McLaughlin lesion injury in which is an impaction type fracture of the anteromedial aspect of the humeral head.

Diagnosis of Shoulder Instability

The Diagnosis of shoulder instability are following 

History

  • A popping sensation may feel or not
  • Sudden onset of pain with decreased range of motion may feel or not.
  • The sensation or sensory function of joint rolling out of the socket.
  • Remember to ask about any previous dislocations that happened or not.
  • When the shoulder dislocates are found, the nerves can get stretched out or not. Some patients report stinging, pinch, and numbness in the arm and forearm at the time of the dislocation.

Physical

The physical examination should confirm by examination with suspected shoulder instability.

  • The range of motion is diminished and painful or painless.
  • In the case of shoulder instability the anterior arm is abducted position and externally rotated in thin patients may be feeling, there may be a prominent humeral head felt anterior or posterior directly, and the void can be seen posteriorly in the shoulder joints.
  • In the case of the shoulder, instability is easy to miss and can be felt, because the arm is in internal rotation movement and adduction movement.
  • In thin patients, or unhealthy patients the prominent head can be palpated posteriorly in most cases.
  • Your doctors or health care provider and practitioners can miss posterior shoulder instability injury easily because the patient appears only to be guarding the extremity and shoulder joint.
  • When performing a detailed neurovascular examination before the reduction is imperative may be felt.
  • The injury to the axillary nerve most often during shoulder instability movement is as high as 40%.
  • Practitioners should record the neuromuscular examination profile before and after any shoulder instability joint.
  • First-time dislocators 
    • The patients presenting after a single acute injury and trauma event typically report a recent history of high-energy trauma, stiffness, or collision impact causing the shoulder instability.
    • Clinicians should inquire regarding:
      • Degree of trauma  in case of high- or low-energy impact mechanisms
      • Sports injury or activity and position may felt
      • Discern and concern in a true dislocation from a subluxation event may be felt in shoulder instability
      • Elicit the requirement for on-field or on-site manual reduction in position; presentation to the emergency department +/- sedation requirements.
  • Chronic cases
    • The patients typically present after having delayed once the range of motion movement limitations begins to impact daily activities significantly.
    • The clinicians should gather knowledge and detailed history for any inciting instability events.
      • The initial injury may be felt and overlooked, and the patient subsequently develops chronic instability recurrence with incidence.
      • The more heightened clinical suspicion is warranted in the setting position with  of:
      • The history of seizures or electrical shock types abnormality.
      • The polytrauma in which the shoulder instability was overlooked or missed and felt.
      • Low-energy, recurrent subluxation cases occur in most cases.
      • The shoulder instability occurs and episodes during sleep may be indicative in case of more complex instability that may involve significant bone loss.
      • The clinicians should elicit and examine for any medical comorbidities and mortality or family history of underlying connective tissue disorders or generalized hyperlaxity on the exam.

Provocative Examination Testing/Maneuvers

  • C-spine / Neck Exam –  In the co-existing cervical radiculopathy and cervical spondylosis with shoulder instability should be ruled out in any situation where the neck or shoulder pathology is considered. Observation of neck posturing, muscular symmetrical positions, palpable tenderness, and active/passive ROM should undergo an evaluation and examination. Special tests that are helpful include the Spurling maneuver, myelopathic testing, reflex testing, and a comprehensive neurovascular examination.
  • Shoulder Exam – The examiners should observe, elicited, and compare bilateral shoulder girdles muscle for any notable asymmetrical position, scapular proper posturing, muscle bulk comparison, or any types of atrophic changes. The skin should be observed properly for the presence of any previous surgical incisions, injury, lacerations, scars tissue formation, erythema with rounded redness, or induration.
  • Shoulder Instability Considerations – The global tissue laxity, erases, spasm should undergo an assessment by examining glenohumeral translation and hypermobility movement at the shoulder joints and other joints around the shoulder in the body if applicable. The hyperlaxity at other joints movements (e.g., elbow and knee hyperextension) may result in the clinical diagnosis that underlying MDI-related diagnoses or connective tissue disorders in the shoulder joint.
  • Anterior Apprehension Test – The anterior apprehension test is performed by lying the patient supine position on the examination table. The examiner positions the shoulder to 90 degrees of abduction and 90 degrees of external rotation movement while applying an anteriorly-directed force to the proximal humerus incorrectly. The test is positive if it reproduces the symptoms of anterior instability are occurs. Apprehension at lower degrees of abduction movement may suggest glenoid bone loss, osteoporosis. The patients may felt the shoulder during the examination, but in most circumstances, the provider can determine or understand if the apprehensive position is seen the patient’s feelings of anterior shoulder instability.
  • Jobe Relocation Test – The Jobe relocation test is utilized with the previous and pre-apprehensive testing maneuver. Once the patient reports a subjective feeling of reproducing the shoulder instability symptoms, pain, swelling, the examiner applies a posteriorly directed force to the joint while keeping the shoulder in the same apprehensive position.  The resolution or improvement of symptoms indicates a positive test result in most cases.
  • Load-and-shift Test  – The examiner uses one hand to apply an axial load through the elbow to center the humeral head within the glenoid joints. An anterior and posterior directed force is then applied at 0-, 45-, and 90-degrees of shoulder abduction movement. Increased translation at increasing degrees of shoulder abduction movement implies a compromise of the IGHL.

Lab Tests

  • Laboratory tests – Leukocytosis is one of the most important tests for shoulder instability that supports the possibility of infection and bone-related disease.
  • Serological test – Blood cultures, urine examination, stool examination, or other possible primary symptoms of shoulder instability, a bone infection that obligatory when a septic infectious shoulder instability is being considered for examination. The and elevated inflammatory condition markers like ESR or CRP include suggesting an infectious or inflammatory disease condition of the shoulder instability.
  • A serum uric acid level – It is often considered by clinicians and doctors when got shoulder instability, tendonitis is suspected, but it is not a reliable and dangerous condition as it may be spuriously elevated or high in acute inflammatory conditions or acutely during a or not.
  • Random blood glucose –  The reference values for a normal random glucose test in an average adult are 80–140mg/dl (4.4–7.8 mmol/l), between 140-200mg/dl (7.8–11.1 mmol/l) is considered pre-diabetes, and ≥ 200 mg/dl is considered diabetes according to ADA guidelines you should visit your doctor or a clinic for additional tests to over sure.
  • Ultrasound – It is basically done to investigate the thickness of the fascia, ligament injury with shoulder instability are likely to have a thickened tendon with the associated fluid collection and that thickness values >4.0 mm that are the diagnostic of in shoulder instability.[]
  • Musculoskeletal ultrasound – It can further visualize the tendon and bony attachment of the thigh sites, muscles, ligaments, and nerves. Ultrasound can also be used to identify the area and extent, nature of the injury shoulder instability and used to evaluate periodically during the recovery phase. The most common findings on ultrasound are focal, fluid, tenosynovitis changes in the common flexor tendon position, how much thickening of the tendon sheath, partial or full-thickness tears, and tear of the tendon. Ultrasound did for dynamic imaging studies, which can provide the additional benefit in regards to evaluation for shoulder dislocation
  • Muscle Biopsy – Muscle biopsy is basically done to investigate abnormal congenital problems such as dutchmen muscular dystrophy, myasthenia graves, hemophilia, etc. A small part of the cell or tissue is collected from the thigh and send to investigate other abnormalities in shoulder instability.

Imaging

  • X-Ray – Conventional x-ray and radiography is the most widely used imaging modality and allows for the detection of bone fractures, osteoporosis, and abnormal pathologies condition like fracture, osteoporosis, erosions, osteonecrosis, osteoarthritis, or a juxta-articular bone tumor, neoplasm, and shoulder instability. Characteristic features of shoulder dislocation and shoulder instability include marginal osteophytes formation in shoulder joint space gradually narrowing, subchondral sclerosis formation in the shoulder instability.
  • CT Scan – High contrast CT scan is more effective to diagnose procedures to investigate shoulder instability. Abnormal tendon, ligament, cartilage, muscle and osteophyte, synovial fluid. It also helps to identify the bone tumor, necrosis, abnormal joint condition, etc.
  • MRI – It is called magnetic radical imaging is also helpful to find the bone conditions, abnormal tendon, ligament, cartilage, muscle and osteophyte, synovial fluid. It also helps to identify the bone tumor, necrosis, abnormal joint condition, shoulder instability. It is the final stage test to confirm that all shoulder instability or any other abnormality suspected others condition forearms pain, such as shoulder pigmentation, soft tissue injury and bone tumors, osteonecrosis, osteomyelitis, arthritis, and stress fracture.[,]
  • Bone scintigraphy – It is the most important test to diagnose bone cancer, neoplasm, fractures, necrosis of bone, and joints. It also helps to identify the tendon, sprained ligament, cartilage, muscle spasm, sprain, and strain with shoulder instability.
  • Nerve Conduction velocity test – It a special test for leg pain or thigh pain. It is the procedure where test the sensation of the peripheral nerve stimuli to send the central nervous system means brain. It helps to identify the sensory and motor nervous system problem from the central to the peripheral cell.

Treatment of Shoulder Instability

The treatment of shoulder instability is following 

Nonoperative Management

  • Physiotherapy – It is one of the most common and effective non-pharmacological treatments in the world. It has a variety of treatment modules to erase acute and chronic pain. It is especially helpful in muscle spasticity, spasms related to tennis elbow or lateral epicondylitis, and elbows upper side pain front side and backside pain, and shoulder dislocation and shoulder instability. Inflammatory and noninflammatory pain is treated by ultrasound therapy, MRI, Shortwave, microwave, wax therapy, IRR, laser therapy, interferential current therapy, iontophoresis, short-wave diathermy (SWD), and pulsed short-wave diathermy (PSWD)search faradaic current, galvanic current therapy, and wax therapy. Some studies have reported good outcomes with physiotherapy regimes of stretching and strengthening, with more favorable results than rest and reduced activity at short-term follow-up in shoulder instability.
  • Deep transverse friction massage – AIt is a special type of massage technique called transverse friction massage is often used in shoulder dislocation and shoulder instability patients. It is applied to the tendons and the muscles, using the tips of one or two fingers to heal shoulder instability.
  • Transcutaneous electrical nerve stimulation (TENS) – It is called  TENS devices that help to transfer electrical impulses that are helpful for the treatment of shoulder instability. These are supposed to keep the pain signals from reaching the brain by blocking pain message signals and increase the secretion of endorphins that are the body’s natural pain killer.
  • Extracorporeal shockwave therapy (ESWT) – It is a physiotherapy device that generates shock or pressure waves that are transferred to the tissue through the skin for healing shoulder instability. This is case assumed that to improve the circulation of blood in the tissue and speed up the healing process of shoulder instability.
  • Eccentric exercises – It is partial help to healing tendons that are the mainstays of physiotherapy regimes. A stable shoulder and scapula function and strength are necessary for correct shoulder functioning; strengthening exercises of the scapular stabilizers that are including the lower trapezius, serratus anterior, and rotator cuff muscles.
  • Percutaneous radiofrequency thermal treatment – A radiofrequency electrode pad is attached percutaneously under an ultrasound guideline which produces a thermal effect in the injured shoulder instability when activated, inducing visual microanatomy and removing all pathological injured tissue. Good outcomes have been reported, and no reduction in tendon size has been observed in this case.
  • Acupuncture – It is the China-oriented acute and chronic treatment system where are needle is used to stimulate the pain receptor to reduce pain. It is also helpful in some spasticity formation pain, stroke, hemiplegia, and chronic rheumatoid arthritis pain in the hand, and shoulder instability
  • Extracorporeal shock-wave therapy (ECSW) – It has been proposed as an alternative to non-operative management for shoulder dislocation and shoulder instability. It worked by the generator of specific frequency sound waves that are applied directly onto the overlying skin of the shoulder instability tendon.
  • The use of low-level laser therapy – It has been proposed due to the stimulating effect of laser on collagen or types 2 collagen production in tendons to increase the healing of shoulder dislocation and shoulder instability. Although laser was not initially viewed as particularly useful among frozen shoulder or adhesive capsulitis therapies and shoulder instability, a recent study has to indicate some short-term benefits when using an adequate dose and wavelength.
  • Armpit stretch – It is done with the support of your healthy arm, lift the arm with the shoulder instability upper direction shoulder dislocation, and rest arms on a surface at about chest level. In this position, gradually or slowly bend your knee joints so that your armpit opens up and you can feel it stretching. Then stand up straight again.
  • External rotation stretch – It is a manual test perform by standing in a doorframe with the affected arm placed out to the side of your body, and the elbow joints bent at a 90-degree angle so that your forearm places is parallel to the floor. Keep the upper arm at your side. Then place the palm of your hand on the doorframe to stop the arm from moving. Now turn your upper body away from the arm to stretch the shoulder. It can be done with the supervision of a physiotherapist
  • Internal rotation stretch – In this case, patients stand with their back to the doorframe. Place the back of your hand on the affected side against your bottom so that your arm is at a slight angle. Now lean the back of that elbow against the doorframe gently “trapping” your elbow to keep it in place and turn your upper body slightly inward towards the arm.
  • Manipulation under anesthesia (MUA) – In this treatment in which the shoulder is freed by rotation while the patient is under short general or local anesthesia. This is usually a day procedure treatment system and generally lasts a maximum of 15 minutes including anesthetic time. There is an increased chance of the risk of homers fractures.
  • Whole-body cryotherapy (WBC) -It involves the exposure of extreme cold to the unclothed body in a chamber that circulates very cold air that is maintained between –110 ℃ to –140 ℃ for 2 minutes to 3 minutes. WBC is assumed to provide anti-inflammatory and analgesic effects to the body.[rx]
  • Diet – Diet may be normal or according to the doctor mentions food you can take for you, such as papaya, banana, potato, nut cereal, seasonal fruits, and drink of water. In your daily routine meal must have magnesium, calcium, iron, zinc, folate, vitamin B complex, Vitamin A, Vitamin C, etc.

Bracing

  • The following brief immobilization and cryotherapy may also be used for pain control during the initial 1 to 2 weeks following acute instability times, formal PT protocols will vary based on the provider-specific preference of your doctor or physiotherapist.
  • In generally following the initial immobilization by bracing, patients will be weaned from sling use, followed by targeted therapy goals focusing on achieving full active and passive ROM, gradual progression to strengthening exercises that focus on dynamic glenohumeral stabilizers, and periscapular stabilizers movement and exercise.
  • When the range of motion (ROM) and strength are comparable to the normal side, sport-specific drills can be initiated, and a return to play, normal life, and athletics activity with a brace can be considered very helpful.
  • The rehabilitation is performed in a supervised setting may improve results, although the time to return to sport normal life, and athletics varies by the program. In most situations, return to play, normal life, and athletics   is given consideration after about 2 to 3 weeks

Medications

  • Non-steroidal anti-inflammatory drugs (NSAIDs) – It is considered to be the fast-acting nonsteroidal anti-inflammatory drugs (NSAIDs) as including acetylsalicylate, aspirin, naproxen, ibuprofen, indomethacin, and etodolac, ketorolac in pain is acute. NSAIDs drugs work by inhibiting cyclo-oxygenase enzyme to prevent the synthesis of prostaglandins, prostacyclin, and thromboxanes. It has also some side effects of aspirin at high doses when used are including tinnitus, hearing loss, and gastric intolerance.[rx]
  • Nerve relaxant –  It is basically used to reduce neuropathic pain, inflammation, nerve root entrapment, myalgia, neuralgia, and fibromyalgia, and frozen shoulder or adhesive capsulitis and shoulder dislocation. Your doctor may prescribe gabapentin, pregabalin, vitamin B1, B6, B12, etc. Major side effects are abdominal pain, nausea- vomiting.
  • Vitamin B1, B6, and B12 – It is essential for neuropathic pain management, pernicious anemia, tennis elbow, with vitamin b complex deficiency pain, paresthesia, numbness, itching with diabetic neuropathy pain, myalgia, shoulder dislocation, and shoulder instability, etc. A side effect may be nausea- vomiting, abdominal pain, cramping [rx]
  • Topical diclofenac, camphor, menthol, and nitroglycerin – or glyceryl trinitrate has shown short-term benefits in the frozen shoulder or adhesive capsulitis but overall results for treatment for tendinopathy or shoulder dislocation, shoulder instability have been mixed depending on the site of application.
  • Oral corticosteroids – These provide short-term pain relief for improved range of motion and function. The benefits often do not last longer than a few weeks, and the result is excellent for the treatment of shoulder instability. Oral medications such as non-steroidal anti-inflammatory drugs (NSAIDs) and oral steroids can be used at the same time. Although the use of oral steroids has some limitations and is described in the literature they are not a commonly used interventional treatment in the UK. Major side effects are increase metabolism, muscle cramp, abdominal pain, electrolyte imbalance, etc.[rx]
  • Intra-articular steroid injections – In shoulder dislocation shoulder instability treatment the intraarticular steroid such as methylprednisolone, and triamcinolone injections have been shown to improve function more quickly, decrease pain, and increase range of motion. Often, patients who received injections early in the shoulder dislocation, shoulder instability course are more likely to obtain a benefit. Multiple injections can be given to provide symptomatic relief permanently.[rx] Major side effects are increase metabolism, muscle cramp, abdominal pain, electrolyte imbalance, etc.[]
  • Hydrosilation or Arthrographic distension – In this treatment modality, the joint is injected with saline and steroid to dilate the glenohumeral capsule, tendons, ligament, or in which increased and dilatated of the joint capsule, sterile saline or other solution such as local anesthetic or steroid are used at the same time in supervision or guided by radiological imaging such as arthrography procedure. This has been shown to reduce pain and improve range of motion and function in the short term. [rx]
  • Suprascapular nerve blocks – It is another treatment procedure that may be beneficial in terms of pain relief but not a movement or increase range of motion of shoulder joints, and repeated joint distension may improve movement.rx]
  • Sodium hyaluronate injection – A small number of diverse studies have found that sodium hyaluronate injection in shoulder instability is very effective that helps to control pain and increase range of motion. It may have a high risk of bias, provide insufficient evidence to make conclusions about the effectiveness of sodium hyaluronate in the treatment of shoulder dislocation.]
  • Calcitonin –  It is a kind of polypeptide hormone secreted from parafollicular cells of the thyroid.  It plays a significant role in managing rheumatoid arthritis, osteoarthritis,  complex regional pain syndrome, fracture, frozen shoulder or adhesive capsulitis, shoulder dislocation, shoulder instability, and metastasis of the bone tumor., And it is also thought to decrease the systemic inflammatory response and stimulate the release of endorphins that are the natural pain killer in the body.
  • Extra-articular collagenase injection – It is pushed into the anterior shoulder capsule midway between the bicipital groove and coracoid at the maximal external rotation in the supervision of the endoscopy procedure. It shows excellent results in an improved functional score, shoulder motion, and pain compared to injection of placebo (0.9% saline/2 mM CaCl2). Patients also benefited from subsequent injections. Side effects include tenderness and ecchymosis at the injection sites, which resolved between 7 and 14 days. MRI obtained or done 3 months after collagenase injection pushing to be sure to the clinically significant injuries to the rotator cuff or surrounding structures of shoulder joints.

Surgical Treatment

The optimal approach and technique to address anterior shoulder instability remain controversial and associated surgical treatment are following

  • Open versus Arthroscopic Repair Techniques – Traditionally, open Bankart repairs offered good to excellent results with minimal risk of redislocation (about 2%) in the setting of minimal and primarily soft tissue-only instability cases.  Arthroscopic procedures theoretically offer advantages of the decreased loss of motion, decreased morbidity, avoidance of subscapularis tenotomy, or associated abnormality and the capacity to address intra-articular pathology; studies have shown a faster return to preoperative muscle strength.A 2017 study reported the surgical treatment procedure in management from 2008 through 2012.  Arthroscopic stabilization procedures are being performed at a rate of greater than 90% and more to manage anterior shoulder instability, shoulder dislocation, with the annual rates increasing each year during the study period.
  • Arthroscopic Bankart Repair – In the setting of primarily soft tissue-based pathology, repair and relocation of the detached capsulolabral complex, injured element in the shoulder joint to its anatomic location are the goals of the surgical technique performance.  Thus, the surgeon aims to restore the static restraining capability of the anterior band of the IGHL.  Various suture anchor devices allow for an anatomic repair of the labrum, and techniques will often include capsular plication to address the pathologically lax capsular structures of the shoulder joint.  This concept becomes popular even more important in the setting of chronic instability in most cases.
  • Bone Loss Considerations – Although the exact percentage of bone loss suggested that will trigger a change in surgical fixation technique that is employed remains debated, more aggressive glenoid fossa augmentation procedures are considered as glenoid bone loss approaches and exceeds 25% in most cases.  Augmentation procedures may include autogenous coracoid transfers the Latarjet technique, the tricortical iliac crest, and various allograft tissue augmentation techniques.  The distal tibial allograft is a commonly utilized technique in the setting of advanced glenoid bone loss or revision surgery.

Indication of Shoulder instability Surgery

Relative indications for nonsurgical management of traumatic anterior shoulder instability include:

  • First-time dislocations or not
  • Osseous defects of the glenoid less than 25% or not or increase
  • Humeral head (i.e., Hill-Sachs) defects less than 25%, non-engaging lesions may be found
  • Athlete factors:
    • Desires to return to sport in-season or late season
    • Noncontact athletic activity
    • Non-overhead/non-throwing athletic activity
    • The proper responses to bracing during competition and able to complete sport-specific drills without instability
    • By contrast, surgical management procedures would be advocated earlier in the management course if the case meets any of the following criteria
  • Associated injuries are present

    • Rotator cuff tear (e.g. >50%) present or not
    • Large bony Bankart lesions; glenoid defects greater than 25% or more.
    • Humeral head lesions e.g., Hill-Sachs contributing to recurrent instability (greater than 25%; engaging Hill-Sachs lesion) or not.
    • Proximal humerus fracture requiring surgical treatment.
    • Irreducible dislocation may be present
  • Other relative surgical indications include, but are not limited to:
    • First-time dislocators and age less than 20 years or more
    • Overhead, throwing athletes or others.
    • Contact sport athletes more quickly or not
    • Primary soft tissue pathology and:
      • Recurrent instability is noted upon return to play for quickly or not.
      • The athlete is unable to tolerate bracing or shoulder restrictions movement.
      • The inability to return to baseline performance level following an initial treatment regimen consisting of brief immobilization exercise, full/painless range of motion (ROM) on the exam, physiotherapy strengthening protocol, supervised sport-specific training system and attempted bracing with the return to play quickly or not.
      • The player is near the end of the season or in the off-season and requests earlier surgical intervention may be needed or not.

Complications of Shoulder Instability

Redislocation Following Surgical Fixation

  • The main complication of anterior shoulder stabilization is recurrent instability that may found in near future.
  • Historically and most open shoulder stabilization procedures correlated with a lower rate of recurrence compared to arthroscopic procedures
  • Recurrence rates: 2% to 9% reported in the literature or more
  • Arthroscopic Bankart procedures have demonstrated recurrence rates of 4% up to 67% depending on the complexity range of shoulder instability, shoulder dislocation pathology in each case
    • Burkhart and De Beer reported the results following arthroscopic Bankart repair
    •  In 2017 multicenter database study reported no difference in rates of revision surgery following open versus arthroscopic Bankart repair procedures
    • With significant bony defects: 67% or more
    • Significant defined as either an engaging Hill-Sachs lesion or an inverted pear glenoid lesion such as inferior glenoid margins are narrower than the superior and central glenoid margins
    • Without significant bony defects: 4% or more
  • Utilizing the previously described ISIS scoring scale for the preoperative, and radiographic shoulder instability parameters, the study reported free instability rates following arthroscopic Bankart repair:

    • 94% with 1 to 2 risk factors such as ISIS score less than or equal to 3
    • 85% with an ISIS score of 4 to 6 points or more
    • 55% with an ISIS score of greater than 6 points

Nerve Injuries

  • In general, nerve injuries typically manifest as transient, sensory neurapraxia may occur.
  • In recent studies have found a lower postoperative rate of nerve injury following arthroscopic (0.3%) versus open (2.2%) Bankart repairs.
    • The axillary nerve in the most common nerve that may be injured is adjacent to the inferior capsule and closest or nearest to the inferior glenoid rim at the 6 o’clock position.
    • The axillary nerve can be injured when placing anteroinferior and inferior positions in the shoulder joints (the 4:30- and 6-o’clock positions, respectively, in the right shoulder) or when repairing capsular lesions or humeral avulsion of the glenohumeral ligament.

Infection

  • No significant difference is appreciated between open versus arthroscopic Bankart repairs
  • 22% rate following arthroscopic Bankart repair may be found.

Implant-related Problems

  • Earlier studies reported up to a 30% rate of implant-related complications (loosening or breakage)
  • Studies included older implant devices and instrumentation metallic staples, bioabsorbable tacks
  • A scientific study reported implant-related complication rates much lower compared to these earlier studies
    • suture-anchor only devices
    • 0.3% implant-related complication rate may increase

References

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