Subacromial Impingement and Bursitis Info In-depth Evidence
Reviewed by Dr Kieran Hirpara, Specialist Orthopaedic Surgeon Last reviewed
What you're feeling
You are likely experiencing a deep ache in the side of your shoulder. This pain often travels down your upper arm. It is caused by subacromial impingement, where tissues get squeezed under the bony roof of your shoulder blade. You may also have bursitis, which is swelling of the fluid-filled sac that cushions this area.
The pain usually worsens when you lift your arm above shoulder height. Simple tasks like reaching for a cup on a high shelf or placing a bag in the boot of your car can become difficult. You might find it hard to sleep on that side. Many patients report that the pain flares up at night, disrupting their rest. It can also feel stiff when you first wake up in the morning.
This discomfort typically builds up after activity. You might feel it more after gardening, painting, or playing sports. The pain often settles with rest, but it can linger. You may notice a sharp catch when you move your arm in certain ways. This happens because the inflamed tissue is being pinched between the bones.
If you have had this pain for at least six months, it is considered persistent. You might have tried rest, ice, or anti-inflammatory medication without lasting relief. Your surgeon will check for specific signs, such as pain when your arm is pushed across your body. They will also look for evidence of mechanical impingement on scans.
It is important to know that your mental health can influence how you experience this pain. However, studies show that patients improve after surgery regardless of whether they have underlying depression or depressive symptoms. The goal of treatment is to relieve the pressure and reduce inflammation. This helps you return to daily activities without the constant ache.
If conservative measures do not help, surgery may be considered. Arthroscopic subacromial decompression is a valid option for those selected according to national guidelines. It aims to reduce pain and improve your quality of life. Your surgeon will use a clinical examination to ensure you are a good candidate for this procedure.
What's actually happening
Your shoulder has a small gap between the top of your arm bone and the bony roof above it. Inside this space sit your rotator cuff tendons and a fluid-filled sac that acts like a shock absorber. When you lift your arm, these structures slide under the bony roof. In subacromial impingement, this space becomes too narrow. The tendons and the shock absorber get pinched or rubbed against the bone every time you move.
This constant rubbing causes inflammation and swelling. The shock absorber becomes irritated, a condition known as bursitis. Your tendons may also develop thickening or small tears from the wear and tear. This is why you feel pain when lifting your arm, especially overhead. The swelling takes up more room in an already tight space, making the pinching worse. It is a cycle of irritation that leads to stiffness and discomfort.
Your surgeon looks for signs of this mechanical pinching. You might have reduced movement or pain during specific strength tests. If non-surgical treatments do not help, we may recommend subacromial decompression. This procedure removes the inflamed tissue and reshapes the bony roof slightly. The goal is to create more room so your tendons can glide smoothly again without being pinched.
We carefully select patients for this surgery based on clear signs of mechanical impingement. Not everyone with shoulder pain needs this operation. We reserve it for cases where the anatomy is clearly causing the problem and conservative care has failed. If you are a candidate, the procedure aims to restore normal movement and reduce pain by addressing the source of the friction.
What we can do about it
Dr Kieran Hirpara, an upper-limb surgeon at Mater Private Hospital Rockhampton, starts with the least invasive options that suit your condition. We begin with self-management and physiotherapy. This is the mainstay of treatment. You will learn exercises to strengthen your shoulder muscles. This helps create more space in the joint. We advise you to change activities that cause pain. You should give this approach at least six weeks to work. If your pain persists, we may extend this period. The goal is to reduce inflammation and improve movement without surgery.
If exercise alone is not enough, we consider medical management. You may take pain medication or anti-inflammatories to control discomfort. We can also offer injections into the shoulder. Cortisone injections reduce swelling and pain. These effects often last for several weeks or months. This can help you participate more fully in physiotherapy. Other injection types, such as hyaluronic acid or platelet-rich plasma, are sometimes used. These aim to lubricate the joint or promote healing. We discuss which option fits your specific symptoms and health history.
Surgery is considered only when conservative care has not given enough improvement. We look for specific signs that you have mechanical impingement. These include pain for at least six months and a positive test result in the clinic. Imaging must also show physical narrowing in the shoulder. If these criteria are met, we may recommend arthroscopic subacromial decompression. This procedure removes bone spurs or inflamed tissue to relieve pressure. It is a valid treatment that reduces pain and improves quality of life for selected patients.
Patients are generally referred to our clinic by their GP; if a physiotherapist has suggested you see us, you will still need a referral from your GP in order to be eligible for the Medicare rebate. A clinic assessment, including history, examination, and imaging where needed, establishes the diagnosis. For degenerative or long-standing problems we usually try non-operative care — activity change, physiotherapy or hand therapy, splinting, and injections — and consider surgery when that has not given enough improvement. For structural or acute problems, surgery may be recommended straight away, without a preceding non-operative trial. We present this as a shared decision, ensuring you understand the potential benefits and risks before proceeding.
What to expect
Your shoulder pain may settle with time, or it may persist. For many people, conservative management is the first step. This includes specific exercise treatment. These exercises are effective and reduce the need for surgery. The benefits of this approach are maintained after 10 years. If your pain does not respond to these measures, your surgeon may consider surgery.
Surgery is typically reserved for cases where pain has lasted at least 6 months. It is also considered if you have a persistently positive Hawkins test. This is a physical exam check for mechanical impingement. Radiologic evidence of this impingement is also required. When these specific criteria are met, subacromial decompression is a valid treatment. It reduces pain and improves quality of life.
If you undergo arthroscopic subacromial decompression, your recovery follows a predictable path. More than 90% of patients manage to return to driving within 4 weeks. You can typically return to work within 6 weeks. If you have calcific deposits removed alongside decompression, it takes longer to return to unrestricted activity without pain. Recovery of subjective shoulder function requires almost 3 months on average in these cases.
Your outlook is generally positive. Patients improved after undergoing subacromial decompression regardless of underlying depression or depressive symptoms. However, the evidence for this procedure is nuanced. There is no current and strong evidence to support subacromial decompression or nonoperative treatment for rotator cuff tendinopathy alone. This requires careful patient selection by your surgeon.
If you are having rotator cuff repair, formal subacromial decompression does not result in improved clinical outcomes up to 2 years. Long-term clinical outcomes were significantly higher in patients treated only with rotator cuff repair. Therefore, this procedure is not routinely added to cuff repairs unless specific mechanical impingement is present.
Arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy or exercise therapy on return to work in patients with shoulder impingement syndrome. This means that for some, the surgical intervention offers similar functional return to non-surgical paths. Your surgeon will help you decide which path is right for you based on your specific symptoms and examination findings.
When to see someone
Ask for a specialist review if you have shoulder pain that has not improved after six months of rest and other treatments. You should also seek help if you notice weakness, instability, or if the pain stops you from sleeping or working. Specific signs include a persistently positive Hawkins test and evidence of mechanical impingement on scans. See your GP if you experience sudden worsening, locking, or giving way. Early assessment helps your surgeon decide if subacromial decompression is the right choice for your specific symptoms and condition.
Advanced reading: the deeper science (optional)
This section goes further than you need for your own treatment decisions. Subacromial impingement is worth the extra reading because it is the shoulder condition where surgery has been tested against a placebo operation — twice, in large randomised trials — and the result changed practice worldwide.
Two trials that compared the operation against pretending to do it
Most surgical evidence compares one operation with another, or with no treatment. Very rarely, a trial compares an operation with a sham — the patient is anaesthetised, the arthroscope is inserted, nothing is decompressed, and neither patient nor assessor knows which was done. That design removes the placebo effect of having had surgery, which is substantial.
The CSAW trial randomised 313 patients three ways: arthroscopic subacromial decompression, investigational arthroscopy only, and no treatment. Both surgical groups did better than no treatment, but the difference was not clinically important — and decompression offered no extra benefit over arthroscopy alone [1].
The FIMPACT trial reached the same conclusion independently. In patients with impingement syndrome, arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy at 24 months [2].
Two well-conducted trials, two countries, the same answer: the part of the operation that removes bone is not the part producing the improvement. Whatever benefit people experienced came from something the sham procedure also delivered.
What that does and does not mean
It does not mean the pain is imagined, or that nothing helps. It means the mechanical explanation — that a bone spur is rubbing on the tendon and shaving it away fixes the problem — is not supported as the mechanism of benefit.
That has consequences for how the condition is framed. The term "impingement" itself embeds the mechanical theory, which is why much of the literature has shifted to "subacromial pain syndrome": a description of where it hurts rather than an unproven claim about why.
So what is left
Non-operative treatment carries the weight, and the comparative evidence is mixed enough to be worth reading carefully. In a network analysis of 3,643 patients, arthroscopic decompression with acromioplasty and physical therapy showed better outcomes across pain, patient-reported measures and range of motion, while corticosteroid injection showed poor outcomes in all three domains — with the authors recommending physical therapy for patients with significant symptoms [3].
Set against the sham-controlled trials, the reasonable synthesis is that structured exercise is the core treatment; injection may relieve pain in the short term but does not perform well over the longer horizon; and surgery has not been shown to add anything beyond what inserting a camera adds.
Where surgery still has a role
None of this applies to a genuine, repairable rotator cuff tear, which is a different diagnosis with its own evidence — covered on the rotator cuff page. The trials above concern shoulders with pain attributed to impingement, not shoulders with a torn tendon. Distinguishing the two is the reason careful assessment matters more here than the choice of operation.
References for the advanced reading
- Beard DJ, Rees JL, Cook JA, Rombach I, Cooper C, Merritt N, et al. Arthroscopic subacromial decompression for subacromial shoulder pain (CSAW): a multicentre, pragmatic, parallel group, placebo-controlled, three-group, randomised surgical trial. Lancet. 2018;391(10118):329-38.
- Paavola M, Malmivaara A, Taimela S, Kanto K, Inkinen J, Kalske J, et al. Subacromial decompression versus diagnostic arthroscopy for shoulder impingement: randomised, placebo surgery controlled clinical trial. BMJ. 2018;362:k2860.
- Lavoie-Gagne O, Farah G, Lu Y, Mehta N, Parvaresh KC, Forsythe B. Physical therapy combined with subacromial cortisone injection is a first-line treatment whereas acromioplasty with physical therapy is best if conservative management fails for impingement syndrome: a systematic review and network meta-analysis. Arthroscopy. 2022;38(8):2511-24.
Evidence & references
This is the clinical evidence summary written for health professionals. It is technical, and it lists the research this page was built from. You do not need to read it to understand your treatment or to make a decision about it.
Overview
- Management of subacromial impingement syndrome includes physical therapy, injections, and surgery for some patients [2].
- There remains a need for high-quality studies of the pathology, etiology, and management of subacromial impingement syndrome [2].
- Current randomized, controlled trial evidence shows no difference in outcomes of shoulder function or pain between surgical and conservative treatment for subacromial impingement syndrome [3].
- Ultrasound guidance is not superior in the subacromial bursa and glenohumeral joint injections in pain or function [4].
- Subacromial pain syndrome (SAPS) should preferably be treated non-operatively [6].
- Subacromial injection with corticosteroids is indicated for persistent or recurrent symptoms of SAPS [6].
- Arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy at 24 months in patients with shoulder impingement syndrome [10].
- Arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy or exercise therapy at 5 years for patients with shoulder impingement syndrome [11].
- Arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy or exercise therapy on return to work in patients with shoulder impingement syndrome [16].
- Arthroscopic subacromial decompression yields good long-term results in the treatment of subacromial impingement for small full-thickness tears [13].
- Adding a large dose of shoulder strengthening to current nonoperative care for patients with subacromial impingement did not result in superior shoulder-specific patient-reported outcomes [14].
- For patients with a long-term disease course, operative treatments may be considered [15].
- Standard arthroscopic subacromial decompression (ASD) surgery is preferred over arthroscopic bursectomy and the open surgical technique for subacromial decompression [15].
- Preserving the subacromial bursa during rotator cuff surgery may lead to better rotator cuff healing when secondary pain is manageable [22].
- Arthroscopic subacromial decompression is a valid treatment, reducing pain and improving quality of life for patients selected for surgery according to the Danish national guidelines [26].
Anatomy & Pathophysiology
- Ultrasound guidance is not superior to landmark-based techniques for subacromial bursa injections regarding pain or function outcomes [4].
- Ultrasound guidance is not superior to landmark-based techniques for glenohumeral joint injections regarding pain or function outcomes [4].
- Ultrasound guidance is superior to landmark-based techniques for bicipital groove injections [4].
- A comprehensive classification of individualized impingements around the anterior aspect of the shoulder has been proposed to address conflicting etiologic theories and improve understanding of diagnosis and treatment [5].
- Imaging abnormalities of the acromioclavicular joint are common in asymptomatic shoulders [7].
- Imaging abnormalities of the subacromial space are common in asymptomatic shoulders [7].
- There is no relationship between acromiohumeral distance (AHD) and pain in adults with subacromial pain syndrome [18].
- There is no between-group difference in AHD in neutral shoulder position between symptomatic and asymptomatic groups [18].
- There is no between-group difference in AHD at 45° shoulder abduction between symptomatic and asymptomatic groups [18].
- There is no between-group difference in AHD at 60° shoulder abduction between symptomatic and asymptomatic groups [18].
- Subacromial notching rates are low following reverse shoulder arthroplasty using a 135° inlay humeral component and a lateralized glenoid [19].
- Subacromial notching is not associated with functional outcomes at short-term follow-up [19].
- Subacromial notching is not associated with range of motion at short-term follow-up [19].
- Subacromial balloon spacer (SBS) implantation in cadaveric models of irreparable rotator cuff tears results in significant improvements in humeral head position at 0° shoulder abduction [31].
- Subacromial balloon spacer (SBS) implantation in cadaveric models of irreparable rotator cuff tears results in significant improvements in humeral head position at 30° shoulder abduction [31].
- Subacromial balloon spacer (SBS) implantation in cadaveric models of irreparable rotator cuff tears results in significant improvements in humeral head position at 60° shoulder abduction [31].
- Subacromial balloon spacers resist superior humeral head migration in cadaveric studies [45].
- Subacromial balloon spacers reduce subacromial pressure in cadaveric studies [45].
- Conservation of sufficient subacromial space may have a significant impact on the passive and active function of reverse shoulder arthroplasty [33].
- Conservation of sufficient coracohumeral space may have a significant impact on the passive and active function of reverse shoulder arthroplasty [33].
- Conservation of scapular posture may have a significant impact on the passive and active function of reverse shoulder arthroplasty [33].
- Understanding moment arms is essential to optimize active force generation in reverse shoulder arthroplasty [33].
- Understanding muscle tensioning is essential to optimize reverse shoulder arthroplasty performance [33].
- Superior capsular reconstruction (SCR) improves glenohumeral superior translation compared with rotator cuff tear at time zero [37].
- Superior capsular reconstruction (SCR) improves subacromial contact pressure compared with rotator cuff tear at time zero [37].
- The improvement in glenohumeral superior translation and subacromial contact pressure with SCR is independent of graft type [37].
- Addressing aberrant movement patterns and facilitating balanced activation of all shoulder muscles may be an appropriate treatment direction for subacromial pain syndrome [34].
- Scapular-focused interventions result in a between-group difference in shoulder abduction range of motion in the short term only [39].
- Patients who are candidates for subacromial decompression have more pronounced range of motion deficits compared to non-candidates [40].
- Patients who are candidates for subacromial decompression do not differ in self-reported shoulder function compared to non-candidates [40].
- Patients who are candidates for subacromial decompression do not differ in strength compared to non-candidates [40].
- Patients who are candidates for subacromial decompression do not differ in pain compared to non-candidates [40].
- A decrease in abduction range of motion is associated with being considered a candidate for subacromial decompression [40].
- A decrease in internal rotation range of motion is associated with being considered a candidate for subacromial decompression [40].
- Increased pain during maximal abduction strength effort is associated with being considered a candidate for subacromial decompression [40].
- The Disabilities of the Arm, Shoulder and Hand (DASH) Questionnaire may not be adequate to assess individuals with subacromial pain syndrome when pain occurs above 120 degrees of arm elevation [42].
- Lifestyle factors including sleep behaviors and shoulder usage patterns are potential associations with subacromial impingement syndrome [48].
- Improving sleep behaviors and optimizing shoulder usage patterns are effective measures to prevent subacromial impingement syndrome [48].
Classification
- Patients presenting with signs and symptoms of subacromial pain syndrome have a high prevalence of conflicting and concomitant diagnoses [1].
- The article proposes a comprehensive classification of all individualized impingements occurring around the anterior aspect of the shoulder, including newly described entities [5].
Clinical Presentation
- Imaging abnormalities of the acromioclavicular joint and subacromial space are common in asymptomatic shoulders [7].
- Synovitis in the subacromial space was milder and not associated with any clinical parameters [8].
- Women aged between 30 and 60 years with subacromial pain syndrome and a calcific deposit of >1.5 cm in length have the highest chance of suffering from symptomatic calcific tendinopathy of the rotator cuff [20].
- Night pain is a common complaint of patients presenting with impingement of the shoulder but cannot be used in isolation as a diagnostic predictor for the presence of a rotator cuff tear [32].
- Examination of the cervical spine in patients with subacromial shoulder pain is variable in randomized controlled trials [24].
Investigations
- Due to low certainty of evidence and significant variation among study populations, further research is needed to clarify prevalence estimates of shoulder abnormalities [7].
- Ultrasound guidance is not superior to non-guided injection for pain or function outcomes in the subacromial bursa and glenohumeral joint [4].
- Ultrasound guidance is superior to non-guided injection in the bicipital groove [4].
- Synovitis in the subacromial space was found to be mild and not associated with any clinical parameters in patients with rotator cuff tears [8].
- Diagnostic and therapeutic practices regarding internal impingement of the shoulder differ between surgeons, with French surgeons relying more on CT-arthrography and intra-articular injections while international surgeons favor MRI and physical therapy [41].
- The acromiohumeral distance is significantly smaller on MRI compared to AP radiographs in shoulders with an intact rotator cuff [47].
- The acromiohumeral distance on MRI should not be used as a decision criterion to assess glenohumeral centering or subacromial space width in shoulders with an intact rotator cuff [47].
- Machine learning-based ultrasomics may be helpful in the preliminary screening of shoulder pain for subacromial impingement syndrome stages [49].
- The subacromial space width is smaller in nearly all rotator cuff pathologies, becomes even smaller as condition severity increases, and is smaller in the case of a complete cuff tear [50].
Treatment
- Ultrasound guidance is not superior to non-guided techniques in the subacromial bursa and glenohumeral joint injections regarding pain or function [4].
- Subacromial pain syndrome should preferably be treated non-operatively, with subacromial injection with corticosteroids indicated for persistent or recurrent symptoms [6].
- Most management regimes for subacromial impingement employ a minimum period of 12 weeks of conservative management incorporating physiotherapy and at least 2 subacromial steroid injections [9].
- Arthroscopic subacromial decompression yields good long-term results in patients with small full-thickness tears [13].
- Adding a large dose of shoulder strengthening to current nonoperative care for subacromial impingement did not result in superior shoulder-specific patient-reported outcomes [14].
- For patients with a long-term disease course, operative treatments may be considered, with standard arthroscopic subacromial decompression (ASD) surgery preferred over arthroscopic bursectomy and open surgical technique [15].
- Arthroscopic subacromial decompression is a valid treatment that reduces pain and improves quality of life for patients selected for surgery according to Danish national guidelines [26].
- Five randomized trials found that formal subacromial decompression does not result in improved clinical outcomes up to 2 years after rotator cuff repair [27].
- There is no evidence from available randomized controlled trials for differences in outcome in pain and shoulder function between conservatively and surgically treated patients with subacromial impingement syndrome [28].
- The evidence on the effectiveness of surgical or conservative treatment of shoulder impingement is limited based on a review of seven randomized controlled trials [35].
- There is little reproducible evidence to support the efficacy of subacromial corticosteroid injection in managing rotator cuff disease [38].
Complications
- Subacromial osteolysis has a relatively high and variable incidence following hook plate fixation for acromioclavicular dislocation [17].
- The primary factor influencing the reported incidence of subacromial osteolysis is the radiological assessment method [17].
- Rates of subacromial notching are low following reverse shoulder arthroplasty with a 135° inlay humeral component and a lateralized glenoid [19].
- When subacromial notching occurs, it is not associated with functional outcomes or range of motion at short-term follow-up [19].
Recovery
- Variation exists in the management regimes offered to patients with subacromial impingement, but most employ a minimum period of 12 weeks of conservative management incorporating physiotherapy and at least 2 subacromial steroid injections [9].
- Arthroscopic subacromial decompression (ASD) in the treatment of subacromial impingement yields good long-term results [13].
- For patients who have a long-term disease course, operative treatments may be considered, with standard ASD surgery preferred over arthroscopic bursectomy and the open surgical technique for subacromial decompression [15].
- Subacromial osteolysis has a relatively high and variable incidence, and the primary factor influencing the reported incidence is the radiological assessment method [17].
- There was no between group difference in acromiohumeral distance (AHD) in neutral shoulder position, shoulder abduction at 45° or 60° [18].
- When subacromial notching occurs following reverse shoulder arthroplasty with a 135° inlay humeral component and a lateralized glenoid, it is not associated with functional outcomes or range of motion at short-term follow-up [19].
- More than half of patients diagnosed with subacromial pain syndrome in specialist care settings do not adhere to recommendations regarding duration of exercise-therapy, but this is not related to symptom improvement [23].
- Major improvements in pain/function were seen at mid- to long-term after isolated arthroscopic subacromial decompression and combined decompression/rotator cuff repair [25].
- Adding a large dose of shoulder strengthening exercises to nonoperative care for 16 weeks did not significantly improve long-term outcomes in terms of shoulder disability, health-related quality of life, sick leave, or surgery rates at 1 year [29].
- There was no evidence of progression of intrinsic rotator cuff pathologic conditions at a mean follow-up of 4.5 years for partial-thickness rotator cuff tears treated with acromioplasty without repair [30].
Key Evidence
- [L3] Patients presenting with signs and symptoms of subacromial pain syndrome have a high prevalence of conflicting and concomitant diagnoses. [1] (10.1177/23259671251332942)
- [L5] Management of subacromial impingement syndrome includes physical therapy, injections, and surgery for some patients, but there remains a need for high-quality studies of the pathology, etiology, and management of the condition. [2] (10.5435/00124635-201111000-00006)
- [L1] Current randomized, controlled trial evidence shows no difference in outcomes of shoulder function or pain between surgical and conservative treatment for subacromial impingement syndrome. [3] (10.2106/jbjs.9202.ebo579)
- [L1] Ultrasound guidance is not superior in the subacromial bursa and glenohumeral joint injections in pain or function. [4] (10.1016/j.arthro.2021.12.013)
- [L4] The article proposes a comprehensive classification of all individualized impingements occurring around the anterior aspect of the shoulder, including newly described entities, to address conflicting theories and improve understanding of their etiologic factors, diagnosis, and treatment. [5] (10.1007/s00264-017-3515-1)
- [Paper] SAPS should preferably be treated non-operatively, with subacromial injection with corticosteroids indicated for persistent or recurrent symptoms. [6] (10.3109/17453674.2014.920991)
- [L2] Due to the low certainty of evidence and significant variation among study populations, further research is needed to clarify these prevalence estimates and to guide evidence-based management of shoulder abnormalities. [7] (10.1186/s13018-024-05378-4)
- [L4] Synovitis in the subacromial space was milder and not associated with any clinical parameters. [8] (10.1177/23259671231207818)
- [L4] Variation exists in the management regimes offered to patients with subacromial impingement, but most employ a minimum period of 12 weeks of conservative management incorporating physiotherapy and at least 2 subacromial steroid injections. [9] (10.1177/1758573215571010)
- [L1] In this controlled trial involving patients with a shoulder impingement syndrome, arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy at 24 months. [10] (10.1136/bmj.k2860)
- [L1] Arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy or exercise therapy at 5 years for patients with shoulder impingement syndrome. [11] (10.1136/bjsports-2020-102216)
- [L3] ASD in the treatment of subacromial impingement yields good long-term results. [13] (10.1016/j.jse.2007.06.020)
- [L1] Adding a large dose of shoulder strengthening to current nonoperative care for patients with subacromial impingement did not result in superior shoulder-specific patient-reported outcomes. [14] (10.1177/03635465211016008)
- [L1] For patients who have a long-term disease course, operative treatments may be considered, with standard ASD surgery preferred over arthroscopic bursectomy and the open surgical technique for subacromial decompression. [15] (10.1097/md.0000000000000510)
- [L1] Arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy or exercise therapy on return to work in patients with shoulder impingement syndrome. [16] (10.1186/s12891-021-04768-7)
- [L1] Subacromial osteolysis has a relatively high and variable incidence, and the primary factor influencing the reported incidence is the radiological assessment method. [17] (10.1016/j.jse.2024.03.018)
- [L1] There was no between group difference in acromiohumeral distance (AHD) in neutral shoulder position, shoulder abduction at 45° or 60°. [18] (10.1038/s41598-020-76704-z)
- [L3] When subacromial notching occurs, it is not associated with functional outcomes or range of motion at short-term follow-up. [19] (10.1016/j.jseint.2024.01.009)
- [L3] This study demonstrates that women aged between 30 and 60 years with subacromial pain syndrome and a calcific deposit of >1.5 cm in length have the highest chance of suffering from symptomatic calcific tendinopathy of the rotator cuff. [20] (10.1016/j.jse.2015.02.024)
- [L5] Preserving the subacromial bursa during rotator cuff surgery may lead to better rotator cuff healing when secondary pain is manageable. [22] (10.1530/eor-2024-0183)
- [L3] More than half of patients diagnosed with subacromial pain syndrome in specialist care settings do not adhere to recommendations regarding duration of exercise-therapy, but this is not related to symptom improvement. [23] (10.1016/j.msksp.2021.102322)
- [L1] Examination of the cervical spine in patients with subacromial shoulder pain is variable in randomized controlled trials. [24] (10.1177/1758573218798023)
- [L3] Major improvements in pain/function were seen at mid- to long-term after isolated arthroscopic subacromial decompression and combined decompression/rotator cuff repair. [25] (10.1016/j.jor.2018.03.004)
- [L4] Arthroscopic subacromial decompression is a valid treatment, reducing pain and improving quality of life for patients selected for surgery according to the Danish national guidelines. [26] (10.1016/j.jse.2017.03.028)
- [L1] Five randomized trials found that formal subacromial decompression does not result in improved clinical outcomes up to 2 years after rotator cuff repair. [27] (10.1016/j.arthro.2012.06.003)
- [L1] According to the best-evidence synthesis, there is no evidence from the available RCTs for differences in outcome in pain and shoulder function between conservatively and surgically treated patients with SIS. [28] (10.1016/j.jse.2009.01.010)
- [L1] Adding a large dose of shoulder strengthening exercises to nonoperative care for 16 weeks did not significantly improve long-term outcomes in terms of shoulder disability, health-related quality of life, sick leave, or surgery rates at 1 year. [29] (10.1177/23259671251374314)
- [L4] There was no evidence of progression of intrinsic rotator cuff pathologic conditions at a mean follow-up of 4.5 years. [30] (10.1177/03635465020300021801)
- [L4] SBS implantation in cadaveric models of irreparable rotator cuff tears results in significant improvements in humeral head position at 0, 30, and 60 of shoulder abduction. [31] (10.1177/03635465221150652)
- [L3] Night pain is a common complaint of patients presenting with impingement of the shoulder but cannot be used in isolation as a diagnostic predictor for the presence of a rotator cuff tear. [32] (10.1111/j.1758-5740.2011.00133.x)
- [L5] Conservation of sufficient subacromial and coracohumeral space and scapular posture may have a significant impact on the passive and active function of reverse shoulder arthroplasty, while understanding moment arms and muscle tensioning is essential to optimize active force generation and RSA performance. [33] (10.3390/jcm12041616)
- [L1] Addressing aberrant movement patterns and facilitating balanced activation of all shoulder muscles may be a more appropriate treatment direction for the future. [34] (10.1177/1758573216660038)
- [L1] Based on the review of seven RCTs, the evidence on effectiveness of surgical or conservative treatment of shoulder impingement was found to be limited. [35] (10.3109/09638288.2014.907364)
- [L1] Independent of graft type, biomechanical studies suggest that SCR improves glenohumeral superior translation and subacromial contact pressure in comparison with RTC tear at time zero. [37] (10.1016/j.arthro.2023.08.025)
- [L1] This systematic review of the available literature indicates that there is little reproducible evidence to support the efficacy of subacromial corticosteroid injection in managing rotator cuff disease. [38] (10.5435/00124635-200701000-00002)
- [L1] A between-group difference in shoulder abduction ROM in the short term only was found. [39] (10.1080/09593985.2018.1423656)
- [L4] A decrease in abduction and internal rotation range of motion, and increased pain during maximal abduction strength effort are associated with being considered a candidate for subacromial decompression, while self-reported shoulder function, pain during the last week, and rotator cuff strength are not. [40] (10.1007/s00167-018-4894-6)
- [L4] Diagnostic and therapeutic practices regarding internal impingement of the shoulder differ between surgeons in France and in other countries, with French surgeons relying more on CT-arthrography and intra-articular injections, while international surgeons favor MRI and physical therapy. [41] (10.1016/j.otsr.2019.09.007)
- [L4] The DASH may not be adequate to assess those with shoulder pain above 120 degrees of arm elevation. [42] (10.1093/ptj/pzab065)
- [L1] In cadaveric studies, subacromial balloon spacers resist superior humeral head migration and reduce subacromial pressure. [45] (10.1016/j.asmr.2020.06.011)
- [L4] The acromiohumeral distance is significantly smaller in the MRI in comparison to AP radiographs in shoulders with an intact rotator cuff and should not be used as a decision criterion on MRI to assess glenohumeral centering or subacromial space width. [47] (10.1007/s00167-020-06090-6)
- [L1] This evidence supports the development of strategies aimed at improving sleep behaviors and optimizing shoulder usage patterns as effective measures to prevent SIS. [48] (10.1186/s12891-024-07345-w)
- [L4] This noninvasive and low-cost approach may be helpful in the preliminary screening of shoulder pain. [49] (10.1002/jum.15914)
- [L4] The subacromial space width is smaller in nearly all rotator cuff pathologies, but becomes even smaller as the severity of the condition increases and is smaller in the case of a complete cuff tear. [50] (10.1016/j.ultras.2003.11.015)
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