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Subacromial Decompression

Arthroscopic subacromial decompression for impingement and bursitis — operation and recovery.

Overview

Subacromial decompression is a valid surgical intervention for shoulder impingement syndrome, indicated when mechanical impingement is confirmed and pain persists despite nonsurgical measures [1]. Proper patient selection based on specific criteria—including pain duration of at least six months, a persistently positive Hawkins test, and radiologic evidence of mechanical impingement—yields excellent outcomes [2, 11]. While conservative management remains the initial mainstay with surgery reserved for treatment failures [7], arthroscopic subacromial decompression effectively reduces pain and improves quality of life in patients selected according to national guidelines [10]. Preoperative clinical examination further aids in optimizing patient selection and improving outcomes [9].

However, the evidence base for this procedure contains significant controversy. There is currently no strong evidence supporting subacromial decompression over nonoperative treatment for rotator cuff tendinopathy, necessitating reliance on clinical judgment and careful patient selection [3]. Furthermore, formal subacromial decompression does not result in improved clinical outcomes up to two years after rotator cuff repair [6] and provides no benefit over diagnostic arthroscopy or exercise therapy regarding return to work [15]. Long-term clinical outcomes are significantly higher in patients treated with rotator cuff repair alone compared to those undergoing concurrent subacromial decompression [5], although short-term follow-up suggests the procedure does not significantly affect arthroscopic rotator cuff repair outcomes [13]. Despite these findings, patients with underlying depression or depressive symptoms still demonstrate improvement following the procedure [4].

Anatomy & Pathophysiology

Osseous Morphology and Critical Shoulder Angle

Acromial Shape: Classic anterolateral acromioplasty remains indicated for Type III acromion, severe tendinopathy, and bursal-sided tears [46]. While peak gliding resistance between the supraspinatus tendon and coracoacromial arch is significantly higher in specimens with a hooked acromion [42], acromioplasty does not result in a statistically significant improvement in shoulder function in subacromial pain syndrome patients with different types of acromial shapes [29]. Arthroscopic rotator cuff repair with concomitant acromioplasty may contribute to superior functional outcomes and reduced reoperation rates in the long-term postoperation, particularly in patients with Type III acromion morphology [45].

Critical Shoulder Angle (CSA): Anterolateral acromioplasty producing a flat acromion undersurface did not result in a significant change of the critical shoulder angle in the study population [41]. Classic anterolateral acromioplasty does not consistently modulate lateral acromial overcoverage or clinically meaningfully change the critical shoulder angle [46]. However, acromioplasty can significantly reduce the critical shoulder angle, notably in cases of high preoperative critical shoulder angle [43], with lateral acromioplasty showing a more significant effect on reducing the critical shoulder angle compared to anterolateral acromioplasty [43]. There is currently no evidence that reduction of the critical shoulder angle diminishes the risk of developing a rotator cuff tear or re-tear [32]. While relationships of high and low critical shoulder angle are well established, there is not yet widespread clear clinical evidence on potential benefits regarding clinical outcomes for lateral acromioplasty [33].

Ligamentous and Soft Tissue Mechanics

Coracoacromial Arch: Coracoacromial ligament excision and acromioplasty increase the rotator cuff force required to maintain normal glenohumeral biomechanics by 25% to 30% at 150 to 200 N of loading [24]. Peak gliding resistance between the supraspinatus tendon and the coracoacromial arch during combined abduction and internal rotation was significantly reduced after anterolateral acromioplasty in a cadaveric model [42]. Substantial and significant improvement in shoulder comfort and the ability to perform specific shoulder functions can be achieved with repair of full-thickness rotator cuff tears without acromioplasty or section of the coracoacromial ligament [38]. Acromioplasty may not need to be performed following rotator cuff repair, particularly in the setting of normal acromial architecture [39].

Deltoid Integrity: The middle deltoid muscle occupies the entire lateral acromion [48]. Arthroscopic lateral acromioplasty did not weaken the structural or mechanical integrity of the lateral deltoid origin, as neither 5-mm nor 10-mm resections significantly reduced the deltoid's failure load [36].

Kinematics and Functional Deficits

Candidate Selection: Candidates for subacromial decompression have more pronounced range of motion deficits compared to non-candidates [34]. A decrease in abduction and internal rotation range of motion is associated with being considered a candidate for subacromial decompression [34]. Increased pain during maximal abduction strength effort is associated with being considered a candidate for subacromial decompression [34]. Self-reported shoulder function, pain during the last week, and rotator cuff strength do not differ between candidates and non-candidates for subacromial decompression [34].

Outcomes and Indications: Subacromial decompression is indicated for shoulder impingement when there is evidence of mechanical impingement and pain has not responded to nonsurgical measures [1]. Acromioplasty offers statistically modest improvements in shoulder function but does not meaningfully enhance pain relief or reduce re-tear rates [47]. Recovery of subjective shoulder function after arthroscopic removal of chronic symptomatic calcifications of the supraspinatus tendon requires almost 3 months on average [21]. The presence of a cuff tear does not necessitate surgical repair [44]. Superior capsule reconstruction repositioned the superiorly migrated humeral head and restored superior stability in the shoulder joint [37].

Classification

Indications and Patient Selection: Subacromial decompression is considered a good choice for shoulder impingement when there is evidence of mechanical impingement and pain has not responded to nonsurgical measures [1]. Proper indications for shoulder subacromial decompression result in excellent outcomes [2]. The treatment of subacromial impingement syndrome remains controversial, with conservative management being the initial mainstay and surgery reserved for failures [7]. Subacromial decompression may be considered if specific criteria are met, including pain for at least 6 months, a persistently positive Hawkins test, and radiologic evidence of mechanical impingement [11]. Arthroscopic subacromial decompression is presented as an alternative to open anterior acromioplasty in advanced stage II and selected cases of stage III impingement syndrome [16].

Rotator Cuff Repair Context: Long-term clinical outcomes were significantly higher in patients treated only with rotator cuff repair compared to patients who underwent rotator cuff repair with subacromial decompression [5]. Five randomized trials found that formal subacromial decompression does not result in improved clinical outcomes up to 2 years after rotator cuff repair [6]. There is no current and strong evidence to either support subacromial decompression or nonoperative treatment for rotator cuff tendinopathy, requiring surgeons to rely on clinical judgment and careful patient selection [3].

Outcome Evidence and Placebo Controls: Arthroscopic subacromial decompression is a valid treatment that reduces pain and improves quality of life for patients selected for surgery according to the Danish national guidelines [10]. Patients improved after undergoing subacromial decompression regardless of underlying depression or depressive symptoms [4]. In patients with symptoms consistent with shoulder impingement syndrome, arthroscopic subacromial decompression did not differ from diagnostic arthroscopy (placebo control) for shoulder pain at 24 months [14]. The authors argue that high-quality randomized placebo-controlled studies do not fulfill the criteria of high quality when evaluated objectively [12].

Other Considerations: Patients treated by debridement of the calcific deposit and concomitant subacromial decompression required a longer time to return to unrestricted activity without pain [8]. The use of a pain pump after arthroscopic subacromial decompression did not have any long-term effects on the patients' recovery, return to work, or final result at the minimum 2-year follow-up [18]. The number of patients undergoing subacromial decompression alone rose by 746.4% from 2000/2001 to 2009/2010 in England [20].

Clinical Presentation

Subacromial decompression is indicated for shoulder impingement when mechanical impingement is confirmed and pain persists despite nonsurgical measures [1]. Specific criteria for considering this procedure include pain lasting at least 6 months, a persistently positive Hawkins test, and radiologic evidence of mechanical impingement [11]. While proper patient selection yields excellent outcomes [2], the treatment of subacromial impingement syndrome remains controversial, with conservative management serving as the initial mainstay and surgery reserved for failures [7]. There is currently no strong evidence supporting subacromial decompression over nonoperative treatment for rotator cuff tendinopathy, necessitating reliance on clinical judgment and careful patient selection [3].

Preoperative clinical examination aids in improving patient outcomes and refining selection for subacromial decompression [9]. Arthroscopic subacromial decompression is a valid treatment that reduces pain and improves quality of life for patients selected according to Danish national guidelines [10]. However, in patients with symptoms consistent with shoulder impingement syndrome, arthroscopic subacromial decompression did not differ from diagnostic arthroscopy for shoulder pain at 24 months [14]. Furthermore, the procedure provided no benefit over diagnostic arthroscopy or exercise therapy regarding return to work [15].

Outcomes in Rotator Cuff Repair: Long-term clinical outcomes were significantly higher in patients treated with rotator cuff repair alone compared to those who underwent repair with subacromial decompression [5]. Five randomized trials found that formal subacromial decompression does not result in improved clinical outcomes up to 2 years after rotator cuff repair [6]. At short-term follow-up, subacromial decompression did not significantly affect the outcome of arthroscopic rotator cuff repair [13]. There is no need to perform subacromial decompression in partial bursal-sided rotator cuff repairs to obtain a good result [19].

Patient Selection Factors: Patients improved after undergoing subacromial decompression regardless of underlying depression or depressive symptoms [4]. Multiple surgeon and practice factors, including years in practice, fellowship training, volume, and academic practice, are associated with changes in subacromial decompression use during rotator cuff repair [28]. Authors argue that high-quality randomized placebo-controlled studies do not fulfill the criteria of high quality when evaluated objectively [12].

Adjunct Procedures and Complications: Patients treated by debridement of calcific deposits and concomitant subacromial decompression required a longer time to return to unrestricted activity without pain [8]. Patients suffering from persistent AC joint pain largely benefit from arthroscopic distal clavicle resection with arthroscopic subacromial decompression through symptom relief and improved quality of life [27]. Arthroscopic subacromial decompression seems to reduce the prevalence of rotator cuff tears in impingement patients [17]. Arthroscopic subacromial decompression is presented as an alternative to open anterior acromioplasty in advanced stage II and selected cases of stage III impingement syndrome [16].

Investigations

Plain radiography: Specific criteria for considering subacromial decompression include radiologic evidence of mechanical impingement [11]. Arthroscopic subacromial decompression is presented as an alternative to open anterior acromioplasty in advanced stage II and selected cases of stage III impingement syndrome [16].

MRI: Preoperative clinical examination may aid in improving patient outcome and especially patient selection for subacromial decompression [9]. Arthroscopic subacromial decompression seems to reduce the prevalence of rotator cuff tears in impingement patients [17].

CT: Preoperative imaging with 3D CT may assist surgeons in performing arthroscopic suprascapular nerve decompression [49].

Other Considerations: Conservative management is the initial mainstay for the treatment of subacromial impingement syndrome, with surgery reserved for failures [7]. Subacromial decompression is considered a good choice for shoulder impingement if there is evidence of mechanical impingement with pain not responding to nonsurgical measures [1]. Proper indications for shoulder subacromial decompression result in excellent outcomes [2]. Specific criteria for considering subacromial decompression include pain for at least 6 months and a persistently positive Hawkins test [11]. There is no current and strong evidence to either support subacromial decompression or nonoperative treatment for rotator cuff tendinopathy, requiring surgeons to rely on clinical judgment and careful patient selection [3]. Patients improved after undergoing subacromial decompression regardless of underlying depression or depressive symptoms [4]. 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 [10].

Regarding rotator cuff pathology, long-term clinical outcomes resulted significantly higher in patients treated only with rotator cuff repair compared to patients who underwent rotator cuff repair with subacromial decompression [5]. Five randomized trials found that formal subacromial decompression does not result in improved clinical outcomes up to 2 years after rotator cuff repair [6]. At short-term follow-up, subacromial decompression did not seem to significantly affect the outcome of arthroscopic rotator cuff repair [13]. In patients with symptoms consistent with shoulder impingement syndrome, arthroscopic subacromial decompression did not differ from diagnostic arthroscopy for shoulder pain at 24 months [14]. Arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy or exercise therapy on return to work in patients with shoulder impingement syndrome [15]. Authors argue that high-quality randomized placebo-controlled studies do not fulfill the criteria of high quality when evaluated objectively [12].

For calcific and cystic pathology, patients treated by debridement of the calcific deposit and concomitant subacromial decompression required a longer time to return to unrestricted activity without pain [8]. Arthroscopic subcoracoid cyst decompression restores subscapularis tendon elasticity and shoulder function, with larger cysts (> 2.2 cm³) signaling advanced pathology [50]. Excellent results were found with arthroscopic resection of the acromioclavicular joint and concomitant subacromial decompression [51].

Treatment

Non-Operative

Conservative management remains the initial mainstay for the treatment of subacromial impingement syndrome, with surgery reserved for failures [7]. Following nonoperative treatment for at least 6 weeks, subacromial decompression is a viable and good surgical option for the treatment of shoulder impingement with an intact rotator cuff [30]. There is no current and strong evidence to either support subacromial decompression or nonoperative treatment for rotator cuff tendinopathy, requiring surgeons to rely on clinical judgment and careful patient selection [3].

Operative

Indications: Subacromial decompression is considered a good choice for shoulder impingement if there is evidence of mechanical impingement and pain has not responded to nonsurgical measures [1]. Proper indications for shoulder subacromial decompression result in excellent outcomes [2]. Subacromial decompression should be considered if specific criteria are met, including pain for at least 6 months, a persistently positive Hawkins test, and radiologic evidence of mechanical impingement [11]. Preoperative clinical examination may aid in improving patient outcome and especially patient selection for subacromial decompression [9]. Patients improved after undergoing subacromial decompression regardless of underlying depression or depressive symptoms [4].

Surgical Approach / Technique: Arthroscopic subacromial decompression is a valid treatment that reduces pain and improves quality of life for patients selected for surgery according to the Danish national guidelines [10]. Arthroscopic subacromial decompression is presented as an alternative to open anterior acromioplasty in advanced stage II and selected cases of stage III impingement syndrome [16]. Subacromial decompression via open acromioplasty and tuberoplasty, combined with glenosphere exchange, successfully resolved symptomatic subacromial impingement and restored function in a patient with acromion fracture nonunion following reverse shoulder arthroplasty [22]. A simplified subacromial arthroscopic technique allows for decompression of the suprascapular nerve at the suprascapular notch and spinoglenoid notch while providing a facile, effective method to concomitantly evaluate and treat comorbid shoulder pathology [25].

Adjuncts: The use of a pain pump after arthroscopic subacromial decompression did not have any long-term effects on the patients' recovery, return to work, or final result at the minimum 2-year follow-up [18]. Patients treated by debridement of the calcific deposit and concomitant subacromial decompression required a longer time to return to unrestricted activity without pain compared to other treatments [8].

Other Considerations: Long-term clinical outcomes were significantly higher in patients treated only with rotator cuff repair (RCR) compared to patients who underwent RCR with subacromial decompression [5]. Five randomized trials found that formal subacromial decompression does not result in improved clinical outcomes up to 2 years after rotator cuff repair [6]. There is no need to perform subacromial decompression in partial bursal-sided rotator cuff repairs to obtain a good result [19]. In patients with symptoms consistent with shoulder impingement syndrome, arthroscopic subacromial decompression did not differ from diagnostic arthroscopy (placebo control) for shoulder pain at 24 months [14]. The authors argue that high-quality randomized placebo-controlled studies do not fulfill the criteria of high quality when evaluated objectively [12]. Surgical repair results in significantly improved outcomes when compared with either conservative treatment or subacromial decompression alone for degenerative rotator cuff tears in older patients [26].

Complications

Other Considerations: Subacromial decompression combined with removal of calcific deposits results in a longer time to return to unrestricted activity without pain compared to debridement alone [8]. Formal subacromial decompression does not result in improved clinical outcomes up to 2 years after rotator cuff repair [6], and while it does not significantly affect the outcome of arthroscopic rotator cuff repair at short-term follow-up [13], there is no statistically significant difference in subjective outcome after arthroscopic rotator cuff repair with or without acromioplasty at intermediate follow-up [5]. Conversely, arthroscopic rotator cuff repair with subacromial decompression results in significantly lower long-term clinical outcomes compared to rotator cuff repair alone [5]. Prior subacromial decompression is an independent risk factor for acromial stress fracture after reverse total shoulder arthroplasty, conferring a 26% higher risk [55]. Radiofrequency-based plasma microtenotomy yields equivalent outcomes to arthroscopic subacromial decompression for rotator cuff tendinosis, questioning the need for the more extensive decompression procedure [54]. Arthroscopic subacromial decompression seems to reduce the prevalence of rotator cuff tears in impingement patients over a 15-year period [17].

Thromboembolism: A case of pulmonary embolism due to subclavian venous thrombosis has been reported following rotator cuff tendon repair [53].

Other Considerations: The overall rate of arthroscopic subacromial decompression has declined in recent years, primarily due to a large decrease in the incidence of isolated subacromial decompression without rotator cuff repair [52]. The number of patients undergoing subacromial decompression alone rose by 746.4% from 2000/2001 to 2009/2010 in England [20], whereas operations for rotator cuff repair alone peaked in 2008/2009 and declined considerably in 2009/2010 in England [20].

Recovery

Light activity (weeks): Patients typically manage to return to driving within 4 weeks and to work within 6 weeks following arthroscopic subacromial decompression and acromio-clavicular joint excision [23]. In contrast, patients treated by debridement of the calcific deposit and concomitant subacromial decompression required a longer time to return to unrestricted activity without pain [8]. Arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy or exercise therapy on return to work in patients with shoulder impingement syndrome [15].

Full activity (months): Recovery of subjective shoulder function required almost 3 months on average following arthroscopic removal of chronic symptomatic calcifications of the supraspinatus tendon without acromioplasty [21]. The use of a pain pump after arthroscopic subacromial decompression did not have any long-term effects on the patients' recovery, return to work, or final result at the minimum 2-year follow-up [18].

Complete recovery / outcome plateau (months): Long-term clinical outcomes were significantly higher in patients treated only with rotator cuff repair compared to patients who underwent rotator cuff repair with subacromial decompression [5]. Five randomized trials found that formal subacromial decompression does not result in improved clinical outcomes up to 2 years after rotator cuff repair [6]. At short-term follow-up, subacromial decompression did not seem to significantly affect the outcome of arthroscopic rotator cuff repair [13].

Rehabilitation protocol: Conservative management remains the initial mainstay for subacromial impingement syndrome, with surgery reserved for failures [7]. Specific exercise treatment for patients with subacromial pain was effective and reduced the need for surgery with maintained results after 10 years [31].

Functional milestones: Patients improved after undergoing subacromial decompression regardless of underlying depression or depressive symptoms [4]. Proper indications for shoulder subacromial decompression result in excellent outcomes [2]. Preoperative clinical examination may aid in improving patient outcome and especially patient selection for subacromial decompression [9].

Other Considerations: Subacromial decompression is indicated for shoulder impingement when there is evidence of mechanical impingement and pain has not responded to nonsurgical measures [1]. There is no current and strong evidence to support subacromial decompression or nonoperative treatment for rotator cuff tendinopathy, requiring reliance on clinical judgment and careful patient selection [3].

Key Evidence

  • [L5] The panel agreed that subacromial decompression is a good choice for shoulder impingement if there is evidence of mechanical impingement with pain not responding to nonsurgical measures. (10.1016/j.arthro.2021.09.031)
  • [L5] Proper indications for shoulder subacromial decompression result in excellent outcomes. (10.1016/j.arthro.2021.04.023)
  • [L5] There is no current and strong evidence to either support subacromial decompression or nonoperative treatment, requiring surgeons to rely on clinical judgment and careful patient selection. (10.1016/j.arthro.2020.03.024)
  • [L3] Patients improved after undergoing subacromial decompression regardless of underlying depression or depressive symptoms. (10.1016/j.jseint.2023.11.012)
  • [L3] The long term clinical outcomes resulted significantly higher in patients treated only with RCR respect the ones in patients underwent to RCR with subacromial decompression. (10.1186/s12891-019-3032-z)
  • [L1] Five randomized trials found that formal subacromial decompression does not result in improved clinical outcomes up to 2 years after rotator cuff repair. (10.1016/j.arthro.2012.06.003)
  • [L5] The treatment of subacromial impingement syndrome remains controversial, with conservative management being the initial mainstay and surgery reserved for failures. (10.1111/j.1758-5740.2012.00205.x)
  • [L3] Patients treated by debridement of the calcific deposit and concomitant subacromial decompression required a longer time to return to unrestricted activity without pain. (10.1016/j.jse.2010.10.038)
  • [L2] This study may aid in improving patient outcome and especially patient selection for subacromial decompression. (10.1007/s00167-013-2386-2)
  • [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. (10.1016/j.jse.2017.03.028)
  • [Letter] They suggest considering subacromial decompression if specific criteria are met, including pain for at least 6 months, persistently positive Hawkins test, and radiologic evidence of mechanical impingement. (10.1016/j.arthro.2020.03.023)
  • [Letter] The authors argue that the referenced high-quality randomized placebo-controlled studies do not fulfill the criteria of high quality when evaluated objectively, despite the debate surrounding subacromial decompression. (10.1016/j.arthro.2022.06.011)
  • [L1] At short-term follow-up, subacromial decompression did not seem to significantly affect the outcome of arthroscopic rotator cuff repair. (10.1016/j.arthro.2006.10.011)
  • [L1] In patients with symptoms consistent with shoulder impingement syndrome, arthroscopic subacromial decompression did not differ from diagnostic arthroscopy (placebo control) for shoulder pain at 24 months. (10.2106/jbjs.18.01342)
  • [L1] Arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy or exercise therapy on return to work in patients with shoulder impingement syndrome. (10.1186/s12891-021-04768-7)
  • [L4] Arthroscopic subacromial decompression is presented as an alternative to open anterior acromioplasty in advanced stage II and selected cases of stage III impingement syndrome. (10.1016/j.arthro.2009.10.003)
  • [L3] Arthroscopic subacromial decompression seems to reduce the prevalence of rotator cuff tears in impingement patients. (10.1016/j.jse.2009.04.014)
  • [L2] According to this study, the use of a pain pump after arthroscopic subacromial decompression did not have any long-term effects on the patients' recovery, return to work, or final result at the minimum 2-year follow-up. (10.1016/j.arthro.2008.07.013)
  • [L5] There is no need to perform subacromial decompression in partial bursal-sided rotator cuff repairs to obtain a good result. (10.1016/j.arthro.2017.02.015)
  • [L4] The number of patients undergoing subacromial decompression alone rose by 746.4% from 2000/2001 to 2009/2010, while operations for rotator cuff repair alone peaked in 2008/2009 and declined considerably in 2009/2010. (10.1302/0301-620x.96b1.32556)
  • [L4] However, recovery of subjective shoulder function required almost 3 months on average. (10.1177/2325967114533646)
  • [L4] Subacromial decompression via open acromioplasty and tuberoplasty, combined with glenosphere exchange, successfully resolved symptomatic subacromial impingement and restored function in a patient with acromion fracture nonunion following reverse shoulder arthroplasty. (10.1016/j.xrrt.2024.11.003)
  • [L3] The results obtained in the present study suggest that more than 90% of the patients manage to return to driving within 4 weeks and to work within 6 weeks following arthroscopic subacromial decompression and acromio-clavicular joint excision. (10.1111/j.1758-5740.2010.00048.x)
  • [L5] At 150 to 200 N of loading, CAL excision and acromioplasty increase the rotator cuff force required to maintain normal glenohumeral biomechanics by 25% to 30%. (10.1016/j.jse.2015.10.022)
  • [L4] This report describes a simplified subacromial arthroscopic technique for decompression of the suprascapular nerve at the suprascapular notch and spinoglenoid notch while providing the surgeon with a facile, effective method to concomitantly evaluate and treat comorbid shoulder pathology. (10.1016/j.arthro.2008.10.024)
  • [L1] Surgical repair results in significantly improved outcomes when compared with either conservative treatment or subacromial decompression alone for degenerative rotator cuff tears in older patients. (10.1302/0301-620x.101b9.bjj-2018-1591.r1)
  • [L4] Patients who suffer from persistent AC joint pain largely benefit from arthroscopic DCR with arthroscopic subacromial decompression through relief of symptoms and improved quality of life, including those with a high self-reported and preoperative level of shoulder function. (10.1016/j.jseint.2022.07.002)
  • [L3] Although subacromial decompression use during rotator cuff repair appears to be decreasing, multiple surgeon and practice factors (years in practice, fellowship training, volume, and academic practice) are associated with a change in subacromial decompression use. (10.1016/j.jhsa.2024.02.002)
  • [Letter] Acromioplasty does not result in a statistically significant improvement in shoulder function in SAPS patients with different types of acromial shapes, and larger randomized trials are warranted to detect smaller clinically relevant treatment effects. (10.1016/j.jse.2017.11.006)
  • [L5] Following nonoperative treatment for at least 6 weeks, SAD is a viable and good surgical option for the treatment of shoulder impingement with an intact rotator cuff. (10.1016/j.arthro.2019.06.012)
  • [L2] Specific exercise treatment for patients with subacromial pain was effective and reduced the need for surgery with maintained results after 10 years. (10.1016/j.jse.2024.10.027)
  • [L5] The editorial recommends the referenced anatomic cadaver study for its scientific quality but states that there is currently no evidence that reduction of the critical shoulder angle diminishes the risk of developing a rotator cuff tear or re-tear, and further clinical studies are required. (10.1016/j.arthro.2016.01.008)
  • [L5] The authors state that while the relationships of high and low critical shoulder angle are well established and lateral acromioplasty is performed in daily practice, there is not yet widespread clear clinical evidence on potential benefits regarding clinical outcomes. (10.1016/j.arthro.2021.11.002)
  • [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. (10.1007/s00167-018-4894-6)
  • [L1] Patients treated with SSN blocks had less pain overall, which led to a decreased need for analgesics in comparison to the subacromial infiltration and placebo groups. (10.1016/j.arthro.2011.05.016)
  • [L5] Arthroscopic lateral acromioplasty did not weaken the structural or mechanical integrity of the lateral deltoid origin, as neither 5-mm nor 10-mm resections significantly reduced the deltoid's failure load. (10.1016/j.arthro.2016.08.015)
  • [L5] Superior capsule reconstruction repositioned the superiorly migrated humeral head and restored superior stability in the shoulder joint. (10.1177/0363546515608652)
  • [L3] The study concluded that substantial and significant improvement in shoulder comfort and the ability to perform specific shoulder functions can be achieved with repair of full-thickness rotator cuff tears without acromioplasty or section of the coracoacromial ligament. (10.2106/jbjs.d.02432)
  • [L1] These data suggest that acromioplasty may not need to be performed following rotator cuff repair, particularly in the setting of normal acromial architecture. (10.1177/2325967113s00101)
  • [L2] Although interscalene block remains the gold standard, subacromial bursa block provides effective, safe, and easily administered postoperative analgesia in patients with an intact rotator cuff undergoing arthroscopic subacromial decompression. (10.1016/j.jse.2007.05.014)
  • [L4] Anterolateral acromioplasty producing a flat acromion undersurface did not result in a significant change of the critical shoulder angle (CSA) in the study population. (10.1016/j.arthro.2022.06.018)
  • [L5] In this cadaveric study, peak gliding resistance between the SSP tendon and the coracoacromial arch during combined abduction and IR was significantly reduced after anterolateral acromioplasty and was significantly higher in specimens with a hooked acromion. (10.1016/j.asmr.2023.100845)
  • [L1] Acromioplasty can significantly reduce the critical shoulder angle, notably in cases of high preoperative CSA, with lateral acromioplasty showing a more significant effect compared to anterolateral acromioplasty. (10.1186/s13018-022-02927-7)
  • [L1] The presence of a cuff tear does not necessitate surgical repair. (10.1177/1758573215620571)
  • [L5] Emerging evidence suggests that arthroscopic rotator cuff repair with concomitant acromioplasty may contribute to superior functional outcomes and reduced reoperation rates in the long-term postoperation, particularly in patients with Type III acromion morphology, although outcomes remain dependent on patient and surgical factors. (10.1016/j.arthro.2024.09.007)
  • [L5] Classic anterolateral acromioplasty does not consistently modulate lateral acromial overcoverage or clinically meaningfully change the critical shoulder angle, though it remains indicated for type III acromion, severe tendinopathy, and bursal-sided tears. (10.1016/j.arthro.2022.08.006)
  • [L1] Acromioplasty offers statistically modest improvements in shoulder function but does not meaningfully enhance pain relief or reduce re-tear rates. (10.5397/cise.2025.00458)
  • [L5] The middle deltoid muscle occupies the entire lateral acromion. (10.1016/j.asmr.2020.06.014)
  • [L5] Preoperative imaging with 3D CT may assist surgeons in performing arthroscopic SSN decompression. (10.1016/j.jse.2014.07.018)
  • [L3] Arthroscopic subcoracoid cyst decompression restores subscapularis tendon elasticity and shoulder function, with larger cysts (> 2.2 cm³) signaling advanced pathology. (10.1186/s12891-025-09068-y)
  • [L4] We found excellent results with arthroscopic resection of the acromioclavicular joint and concomitant subacromial decompression. (10.2106/00004623-200103000-00003)
  • [L3] The overall rate of arthroscopic subacromial decompression has declined in recent years, primarily due to a large decrease in the incidence of aSAD without rotator cuff repair as an isolated treatment for rotator cuff disorders. (10.1016/j.arthro.2021.05.019)
  • [L4] This is the first reported case of pulmonary embolism due to subclavian venous thrombosis following rotator cuff tendon repair. (10.1016/j.jse.2008.02.001)
  • [L1] Both procedures were associated with significant improvement postoperatively, but the RF-based plasma microtenotomy procedure draws into question the need for a more extensive procedure such as subacromial decompression in this patient population. (10.1016/j.arthro.2007.04.018)
  • [L3] Prior subacromial decompression is an independent risk factor for acromial stress fracture after reverse total shoulder arthroplasty, conferring a 26% higher risk. (10.1016/j.jseint.2025.05.014)
  • [L1] On the basis of the currently available literature, there is no statistically significant difference in subjective outcome after arthroscopic rotator cuff repair with or without acromioplasty at intermediate follow-up. (10.1016/j.arthro.2011.11.022)

See Also

References

[1] Subacromial Decompression in Patients With Shoulder Impingement With an Intact Rotator Cuff: An Expert Consensus Statement Using the Modified Delphi Technique Comparing North American to European Shoulder Surgeons. Arthroscopy. 2021. DOI: 10.1016/j.arthro.2021.09.031

[2] Proper Indications for Shoulder Subacromial Decompression Result in Excellent Outcomes. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2021. DOI: 10.1016/j.arthro.2021.04.023

[3] No Indications for Subacromial Decompression in Rotator Cuff Tendinopathy: A Level I Evidence Clinical Guideline. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2020. DOI: 10.1016/j.arthro.2020.03.024

[4] Arthroscopic subacromial decompression improved outcomes in situationally depressed patients compared to clinically depressed or nondepressed patients. JSES International. 2024. DOI: 10.1016/j.jseint.2023.11.012

[5] Arthroscopic rotator cuff repair with and without subacromial decompression is safe and effective: a clinical study. BMC Musculoskeletal Disorders. 2020. DOI: 10.1186/s12891-019-3032-z

[6] The Changing Role of Acromioplasty. Arthroscopy. 2012. DOI: 10.1016/j.arthro.2012.06.003

[7] Current Concepts in Subacromial Impingement and the Role of Acromioplasty. Shoulder & Elbow. 2012. DOI: 10.1111/j.1758-5740.2012.00205.x

[8] Calcific tendonitis of the shoulder: is subacromial decompression in combination with removal of the calcific deposit beneficial?. Journal of Shoulder and Elbow Surgery. 2011. DOI: 10.1016/j.jse.2010.10.038

[9] Predictive value of preoperative clinical examination for subacromial decompression in impingement syndrome. Knee Surgery, Sports Traumatology, Arthroscopy. 2013. DOI: 10.1007/s00167-013-2386-2

[10] Acromioplasty in patients selected for operation by national guidelines. Journal of Shoulder and Elbow Surgery. 2017. DOI: 10.1016/j.jse.2017.03.028

[11] Author Reply: Arthroscopic Subacromial Decompression. What Are the Indications? A Level V Evidence Clinical Guideline. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2020. DOI: 10.1016/j.arthro.2020.03.023

[12] Regarding “Subacromial Decompression in Patients With Shoulder Impingement With an Intact Rotator Cuff: An Expert Consensus Statement Using the Modified Delphi Technique Comparing North American to European Shoulder Surgeons”. Arthroscopy. 2022. DOI: 10.1016/j.arthro.2022.06.011

[13] Arthroscopic Rotator Cuff Repair With and Without Subacromial Decompression: A Prospective Randomized Study. Arthroscopy. 2007. DOI: 10.1016/j.arthro.2006.10.011

[14] In Shoulder Impingement Syndrome, Subacromial Decompression Did Not Differ from Diagnostic Arthroscopy for Shoulder Pain at 24 Months. Journal of Bone and Joint Surgery. 2019. DOI: 10.2106/jbjs.18.01342

[15] Return to work after subacromial decompression, diagnostic arthroscopy, or exercise therapy for shoulder impingement: a randomised, placebo-surgery controlled FIMPACT clinical trial with five-year follow-up. BMC Musculoskeletal Disorders. 2021. DOI: 10.1186/s12891-021-04768-7

[16] Arthroscopic Subacromial Decompression: Analysis of One‐ to Three‐Year Results. Arthroscopy. 2010. DOI: 10.1016/j.arthro.2009.10.003

[17] Fewer rotator cuff tears fifteen years after arthroscopic subacromial decompression. Journal of Shoulder and Elbow Surgery. 2010. DOI: 10.1016/j.jse.2009.04.014

[18] Long‐term Effect of the Use of a Pain Pump After Arthroscopic Subacromial Decompression. Arthroscopy. 2008. DOI: 10.1016/j.arthro.2008.07.013

[19] Editorial Commentary: Subacromial Decompression Is Unnecessary in Most Routine Rotator Cuff Repairs. Arthroscopy. 2017. DOI: 10.1016/j.arthro.2017.02.015

[20] Temporal trends and geographical variation in the use of subacromial decompression and rotator cuff repair of the shoulder in England. The Bone & Joint Journal. 2014. DOI: 10.1302/0301-620x.96b1.32556

[21] Arthroscopic Removal of Chronic Symptomatic Calcifications of the Supraspinatus Tendon Without Acromioplasty. Orthopaedic Journal of Sports Medicine. 2014. DOI: 10.1177/2325967114533646

[22] Subacromial decompression for impingement syndrome following type II acromion fracture nonunion. JSES Reviews, Reports, and Techniques. 2025. DOI: 10.1016/j.xrrt.2024.11.003

[23] Return to Work and Driving following Arthroscopic Subacromial Decompression and Acromioclavicular Joint Excision. Shoulder & Elbow. 2010. DOI: 10.1111/j.1758-5740.2010.00048.x

[24] The effect of coracoacromial ligament excision and acromioplasty on the amount of rotator cuff force production necessary to restore intact glenohumeral biomechanics. Journal of Shoulder and Elbow Surgery. 2016. DOI: 10.1016/j.jse.2015.10.022

[25] Arthroscopic Decompression of the Suprascapular Nerve at the Spinoglenoid Notch and Suprascapular Notch Through the Subacromial Space. Arthroscopy. 2009. DOI: 10.1016/j.arthro.2008.10.024

[26] Surgical repair versus conservative treatment and subacromial decompression for the treatment of rotator cuff tears. The Bone & Joint Journal. 2019. DOI: 10.1302/0301-620x.101b9.bjj-2018-1591.r1

[27] Patient-reported outcomes for arthroscopic resection of the distal clavicle with concomitant arthroscopic subacromial decompression at a 2-year follow-up: a prospective study of 131 consecutive patients. JSES International. 2022. DOI: 10.1016/j.jseint.2022.07.002

[28] Surgeon Factors and Trends Associated With the Use of Subacromial Decompression at the Time of Rotator Cuff Repair. The Journal of Hand Surgery. 2024. DOI: 10.1016/j.jhsa.2024.02.002

[29] Response to Hustedt et al regarding: “Does acromioplasty result in favorable clinical and radiologic outcomes in the management of chronic subacromial pain syndrome? A double-blinded randomized clinical trial with 9 to 14 years' follow-up”. Journal of Shoulder and Elbow Surgery. 2018. DOI: 10.1016/j.jse.2017.11.006

[30] Indications for Arthroscopic Subacromial Decompression. A Level V Evidence Clinical Guideline. Arthroscopy. 2019. DOI: 10.1016/j.arthro.2019.06.012

[31] No need for subacromial decompression in responders to specific exercise treatment: a 10-year follow-up of a randomized controlled trial. Journal of Shoulder and Elbow Surgery. 2025. DOI: 10.1016/j.jse.2024.10.027

[32] Editorial Commentary: Is Lateral Acromioplasty Effective and Safe?. Arthroscopy. 2016. DOI: 10.1016/j.arthro.2016.01.008

[33] Editorial Commentary: Current Indications for Lateral Acromioplasty Include Patients With Elevated Critical Shoulder Angle Plus Subacromial Impingement With Rotator Cuff Pathology or Previous Rotator Cuff Repair. Arthroscopy. 2022. DOI: 10.1016/j.arthro.2021.11.002

[34] Patients who are candidates for subacromial decompression have more pronounced range of motion deficits, but do not differ in self-reported shoulder function, strength or pain compared to non-candidates. Knee Surgery, Sports Traumatology, Arthroscopy. 2018. DOI: 10.1007/s00167-018-4894-6

[35] A Randomized Study of the Effectiveness of Suprascapular Nerve Block in Patient Satisfaction and Outcome After Arthroscopic Subacromial Decompression. Arthroscopy. 2011. DOI: 10.1016/j.arthro.2011.05.016

[36] Impact of Arthroscopic Lateral Acromioplasty on the Mechanical and Structural Integrity of the Lateral Deltoid Origin: A Cadaveric Study. Arthroscopy. 2016. DOI: 10.1016/j.arthro.2016.08.015

[37] Biomechanical Effects of Acromioplasty on Superior Capsule Reconstruction for Irreparable Supraspinatus Tendon Tears. The American Journal of Sports Medicine. 2015. DOI: 10.1177/0363546515608652

[38] Open Rotator Cuff Repair without Acromioplasty. The Journal of Bone and Joint Surgery (American). 2005. DOI: 10.2106/jbjs.d.02432

[39] A Prospective Randomized Trial of Functional Outcomes Following Rotator Cuff Repair With and Without Acromioplasty. Orthopaedic Journal of Sports Medicine. 2013. DOI: 10.1177/2325967113s00101

[40] Subacromial bursa block is an effective alternative to interscalene block for postoperative pain control after arthroscopic subacromial decompression: A randomized trial. Journal of Shoulder and Elbow Surgery. 2008. DOI: 10.1016/j.jse.2007.05.014

[41] Anterolateral Acromioplasty Does Not Change the Critical Shoulder Angle and Acromion Index in a Clinically Relevant Amount. Arthroscopy. 2022. DOI: 10.1016/j.arthro.2022.06.018

[42] Anterolateral Acromioplasty Reduces Gliding Resistance Between the Supraspinatus Tendon and the Coracoacromial Arch in a Cadaveric Model. Arthroscopy, Sports Medicine, and Rehabilitation. 2023. DOI: 10.1016/j.asmr.2023.100845

[43] Does the critical shoulder angle decrease after acromioplasty? A systematic review and meta-analysis. Journal of Orthopaedic Surgery and Research. 2022. DOI: 10.1186/s13018-022-02927-7

[44] Medium- to long-term results of a randomized controlled trial to assess the efficacy of arthoscopic-subacromial decompression versus mini-open repair for the treatment of medium-sized rotator cuff tears. Shoulder & Elbow. 2015. DOI: 10.1177/1758573215620571

[45] Editorial Commentary: Long‐Term, Clinical Outcome of Arthroscopic Rotator Cuff Repair May Be Improved With Concomitant Acromioplasty in Patients With a Type III Acromion. Arthroscopy. 2024. DOI: 10.1016/j.arthro.2024.09.007

[46] Editorial Commentary : Classic Arthroscopic Anterolateral Acromioplasty Does Not Translate to Clinically Meaningful Differences in Lateral Acromial Overcoverage. Arthroscopy. 2022. DOI: 10.1016/j.arthro.2022.08.006

[47] Does acromioplasty enhance arthroscopic rotator cuff repair? A systematic review and meta-analysis of randomized trials. Clinics in Shoulder and Elbow. 2025. DOI: 10.5397/cise.2025.00458

[48] The Lateral Deltoid Originates From the Entire Lateral Wall of the Acromion: MRI and Histologic Cadaveric Analysis Regarding Vertical Lateral Acromioplasty. Arthroscopy, Sports Medicine, and Rehabilitation. 2020. DOI: 10.1016/j.asmr.2020.06.014

[49] Arthroscopic decompression at the suprascapular notch: a radiographic and anatomic roadmap. Journal of Shoulder and Elbow Surgery. 2015. DOI: 10.1016/j.jse.2014.07.018

[50] Defining surgical indications in subcoracoid cysts: 3D volumetric analysis and elastography guide tendon-preserving arthroscopic decompression. BMC Musculoskeletal Disorders. 2025. DOI: 10.1186/s12891-025-09068-y

[51] Arthroscopic Resection of the Distal Aspect of the Clavicle with Concomitant Subacromial Decompression. The Journal of Bone and Joint Surgery-American Volume. 2001. DOI: 10.2106/00004623-200103000-00003

[52] National Trends Show Declining Use of Arthroscopic Subacromial Decompression Without Rotator Cuff Repair. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2021. DOI: 10.1016/j.arthro.2021.05.019

[53] Pulmonary embolism after acromioplasty and rotator cuff repair. Journal of Shoulder and Elbow Surgery. 2008. DOI: 10.1016/j.jse.2008.02.001

[54] Radiofrequency‐Based Plasma Microtenotomy Compared With Arthroscopic Subacromial Decompression Yields Equivalent Outcomes for Rotator Cuff Tendinosis. Arthroscopy. 2007. DOI: 10.1016/j.arthro.2007.04.018

[55] Prior subacromial decompression is a significant risk factor for development of acromial stress fracture after reverse total shoulder arthroplasty. JSES International. 2025. DOI: 10.1016/j.jseint.2025.05.014

[56] The Role of Subacromial Decompression in Patients Undergoing Arthroscopic Repair of Full‐Thickness Tears of the Rotator Cuff: A Systematic Review and Meta‐analysis. Arthroscopy. 2012. DOI: 10.1016/j.arthro.2011.11.022

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