Timing of surgery for terrible triad of the shoulder: a systematic review

Nachiket Deshpande; Moustafa S. Hadi; Eleanor C. Smith; Ayobami L. Ward; Whitney E. Muhlestein; James E. Carpenter; Louis T. Rodgers; Yamaan S. Saadeh

doi:10.5397/cise.2024.00829

Clin Shoulder Elb > Volume 28(2); 2025 > Article

Deshpande, Hadi, Smith, Ward, Muhlestein, Carpenter, Rodgers, and Saadeh: Timing of surgery for terrible triad of the shoulder: a systematic review

Review

Clinics in Shoulder and Elbow 2025; 28(2): 251-262.

Published online: April 25, 2025

DOI: https://doi.org/10.5397/cise.2024.00829

Timing of surgery for terrible triad of the shoulder: a systematic review

Nachiket Deshpande¹, Moustafa S. Hadi², Eleanor C. Smith³, Ayobami L. Ward⁴, Whitney E. Muhlestein⁴, James E. Carpenter⁵, Louis T. Rodgers¹, Yamaan S. Saadeh⁴

¹Department of Neurosurgery, University of Kentucky, Lexington, KY, USA

²College of Human Medicine, Michigan State University, Grand Rapids, MI, USA

³Department of Neurological Surgery, Wake Forest University School of Medicine, Winston-Salem, NC, USA

⁴Department of Neurosurgery, University of Michigan, Ann Arbor, MI, USA

⁵Department of Orthopedic Surgery, University of Michigan, Ann Arbor, MI, USA

Corresponding author: Yamaan S. Saadeh Department of Neurosurgery, University of Michigan, 3552 Taubman Center, 1500 E. Medical Center Drive, Ann Arbor, MI 48109, USA
Tel: +1-734-936-7010, Fax: +1-734-647-9233 Email: yamaans@med.umich.edu

Received: October 16, 2024 Revised: January 16, 2025 Accepted: January 19, 2025

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The terrible triad of the shoulder (STT) is an injury involving anterior shoulder dislocation, rotator cuff tear, and nerve injury. The optimal timing for rotator cuff repair (RCR) remains controversial, with some favoring early intervention and others recommending delaying surgery until nerve recovery. A systematic review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, exploring STT treatment and RCR timing using PubMed, Embase, and Web of Science. The inclusion criteria were studies published in English and involving human subjects. Exclusion criteria included non-English articles, review papers, cadaveric studies, and studies on unrelated conditions. Time to surgery and outcomes related to shoulder and nerve function, such as range of motion, muscle strength, and sensation were analyzed qualitatively. Of 671 articles identified, 28 met inclusion criteria. Most patients underwent surgical RCR and demonstrated excellent functional and neurologic outcomes, with many achieving 150°+ flexion, 110°+ abduction, 4+/5 strength, and resolution of nerve hypoesthesia. RCR timing ranged from 10 days to 6 months, with comparable outcomes regardless of timing. Prompt RCR in STT may be beneficial for maximizing shoulder outcomes, while coexisting nerve injuries should be managed conservatively with watchful waiting, as most recover spontaneously.

Key Words: Braxial plexus injury; Shoulder dislocation; Rotator cuff tear; Shoulder; Operative surgical procedures

INTRODUCTION

The terrible triad of the shoulder (STT) remains a troubling presentation of traumatic injury to the shoulder girdle. Traditionally, the triad is composed of the following constellation of findings: anterior shoulder dislocation (ASD), rotator cuff tear (RCT), and injury to the brachial plexus [1]. The incidence of STT injury is reported to range 2%–18% in ASDs [2] but may be underreported, as evidenced by the predominance of case reports and small studies representing the majority of the existing STT literature. STT may result in inferior outcomes of rotator cuff repair (RCR) due to concomitant nerve injury [3,4].

Management of STT can be complex, as orthopedic and neurologic injuries often require conflicting management strategies, particularly regarding the timing of surgical intervention. Some studies emphasize the importance of early identification and treatment, as delays can result in chronic instability and poor functional outcomes. Specifically, for patients with acute traumatic RCTs and significant weakness, early surgical intervention (specifically within 3 weeks) has been shown to achieve optimal postoperative outcomes, including improved Constant scores, greater shoulder abduction, and active range of motion (ROM) [5]. However, other studies suggest that comparable clinical outcomes can still be achieved if surgery is performed within 4 months following RCT [5,6]. Nonetheless, nerve recovery is typically a gradual process, occurring spontaneously over months to years [7], highlighting the delicate balance between immediate and delayed interventions and the complexity of clinical judgment in STT management. Given the variability in neurological prognosis [3,8], patients who fail to demonstrate neurological improvement may require future surgical intervention for nerve repair or tendon transfer.

On the other hand, the appropriateness of early RCT surgery in the setting of brachial plexus injury remains uncertain. In STT with coexisting RCT and brachial plexus injury, there is concern that tendon repair of a denervated shoulder girdle may not result in optimal postoperative outcomes [9]. Persistent nerve palsy during the postoperative period can impede rehabilitation and subsequent recovery due to impaired shoulder active ROM [10]. Furthermore, recurrent dislocations in STT cases may compromise neurologic recovery and lead to significant morbidity. Early surgical intervention of RCR with labral repair greatly reduces the risk of recurrent dislocation and its associated complications.

Given the existing uncertainty regarding the optimal management of STT, a complex and potentially disabling form of acute shoulder trauma, this study systematically evaluates the impact of surgical timing on clinical outcomes in patients with STT. By reviewing and synthesizing the existing literature, we aim to provide practical guidance for clinicians and surgeons by examining whether early surgery for RCR results in inferior outcomes compared with a delayed approach. This research offers insights into treatment strategies for patients with STT, allowing healthcare providers to optimize both orthopedic and neurological recovery.

METHODS

In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines [11], we conducted a systematic review of the STT literature. PubMed, Embase, and Web of Science were queried for all relevant English articles utilizing the following keywords/phrases: “terrible triad of the shoulder” and “shoulder dislocation AND nerve injury AND rotator cuff injury.” Sources were last searched on January 3, 2025.

Inclusion criteria comprised articles written in English, involving human subjects, and including at least one patient with STT. STT was defined as the following constellation of presenting symptoms: traumatic ASD, RCT, and nerve injury. Case reports, prospective studies, and retrospective studies were included, whereas review articles, commentaries, cadaveric studies, and non-English articles were excluded. Additionally, studies not specifically related to the STT (e.g., terrible triad of the elbow) were also excluded. Other primary reasons for exclusion included articles focusing on conditions other than STT, studies that did not report relevant outcomes (e.g., timing of surgical intervention or orthopedic/neurological recovery) or specify directionality to shoulder dislocation, and those that did not meet the defined inclusion criteria, such as lacking clinical data on human subjects.

Two reviewers were involved in the article screening process. While one reviewer screened the PubMed database, another reviewer screened Embase and Web of Science. For each search engine, a single reviewer screened article titles and/or abstracts for relevance, after which the same reviewer completed a full-text manuscript review of any relevant articles to assess the article’s eligibility for inclusion. A third reviewer was consulted in any cases of uncertainty during the article screening process to minimize the risk of inclusion bias.

Variables of interest were extracted from relevant articles and recorded in Excel (Microsoft). Data collected from each study included the number of patients with terrible triad, management details, and key study outcomes (timing of RCR, outcome of RCR, and whether recovery of nerve palsy occurred). Subsequently, qualitative analysis was conducted to synthesize the findings from the included studies. This approach focused on summarizing and interpreting the reported clinical outcomes, treatment time courses, and management strategies of STT, rather than performing formal statistical analysis. The quality of included studies was assessed by one reviewer using the Risk of Bias Assessment Tool for Nonrandomized Studies (RoBANS) criteria [12].

RESULTS

Initially, 671 articles were identified during our PubMed, Embase, and Web of Science search. Following the exclusion of 226 duplicate articles and 42 non-English articles, 403 articles were screened. Subsequently, 349 articles were excluded based on title and/or abstract, with most being excluded because they focused on the terrible triad of the elbow rather than the shoulder. The remaining 54 articles were sought for full-text review, of which 1 could not be retrieved. Of the 53 remaining articles, 28 met the inclusion criteria (Table 1) [1,7,10,13-37]. A visual depiction of the screening process is illustrated in Fig. 1. The included studies cover 128 cases of traumatic STT, with mechanisms of injury ranging from unwitnessed trauma to occupational accidents, car accidents, and seizures, among others. Of these, 55 cases provided information on the timing of surgery and the course of treatment.

Management of STT

Several studies described the management of STT (Table 1). In the majority of STT cases, the RCT was surgically repaired [1,7,10,13-15,19,20,23-25,28-35]; however, several studies reported that patients were managed conservatively [13,17,18,24,27,37]. While criteria for pursuing surgery were not well elucidated, surgical repair of the RCT was advocated by Johnson and Bayley [15] if there was significant loss of function or pain, whereas Toolanen et al. [26] offered surgery only if the patient had a complete tear.

Neurological Prognosis

Most patients who underwent surgical repair of the RCT experienced excellent functional and neurological recovery [1,7,10,13-15,19,25,28-35,37]. Functional improvement was reported as subjective motor improvement or on the basis of Constant and Western Ontario Rotator Cuff scores [1] and Shoulder Pain and Disability Index [7]. Duration to neurological recovery in these studies ranged from 3 to 12 months. The prognosis for patients treated conservatively is more equivocal, as some patients had good outcomes (defined as return to baseline motor function) [13,24], whereas others had poor recovery (defined as persistent weakness at last follow-up) [18,27]. Regarding prognostic indicators, Marsalli et al. [1] reported that nerve injuries that did not involve the axillary and subscapular nerves had improved outcomes, while Walker and Silver [27] suggested early EMG testing demonstrating partial nerve injury was associated with improved prognosis compared to complete nerve injury.

Timing of RCR in STT Injury

Our search identified 15 articles that included a description of the STT treatment timeline. The duration to surgery varied substantially across studies: from 10 days to 16 months following initial injury (Table 2). Early RCR was defined as within 6 weeks of injury. Outcomes of interest following RCR included standardized scoring systems (Constant, American Shoulder and Elbow Surgeons), visual analog scale, and Shoulder Pain and Disability Index, shoulder strength and ROM, triceps strength, nerve function (resolution of hypoesthesia or electrodiagnostic studies), and occurrence of reoperation (Table 2).

Four patients with explicitly defined hospital courses underwent surgical intervention for nerve injuries (Table 2). One patient underwent neurolysis at the time of RCR [7]. The second patient required neurolysis and RCR for primary axillary nerve palsy 10 months after injury due to persistent neurological deficit. Additionally, two patients underwent nerve transfer procedures to enhance deltoid function prior to RCR surgery [29,34].

Marsalli et al. [1] reported the outcomes of 30 patients who underwent RCR an average of 2.9 months after injury: 21 patients had an axillary nerve injury; 4 patients, suprascapular nerve injury; 2 patients, combined axillary-suprascapular palsy; and 3 patients, nerve injury distal to the shoulder. Patients reported within the remaining studies had predominantly axillary nerve involvement. While several studies advocated for early surgical intervention to address RCT, others delayed surgical intervention until improvement in neurological deficits [10,16,25]. Shoulder and nerve function outcomes were comparable for patients with either early or late RCR (Table 3). However, a more recent case series by Kokkalis et al. [30] suggested that surgical timing may affect outcomes, with better results in patients operated on within 2 to 3 weeks compared to those treated 6 to 22 weeks post-injury. Although their analysis was limited by sample size, their findings highlight the potential benefit of early intervention in STT management, while acknowledging the need for further research.

DISCUSSION

STT is well established and understood, but prompt diagnosis and optimal management remain a challenge for clinicians. Our study suggests that early RCR, even in the presence of brachial plexus injury, results in favorable shoulder and neurological outcomes. Recovery of function in the included studies generally occurred between 3 and 12 months post-injury. There remains little consensus regarding the ideal timing of surgery for RCR in patients with STT. Notwithstanding RCT functional recovery being greatest when RCR is performed within 6 weeks of injury [5,38], the typical timeline for surgical repair is lengthier, as found in the STT literature (Table 2). This may be due to delays in further workup for neurological deficits associated with brachial plexus injury [25]. Some surgeons elect to wait until recovery of nerve palsy and/or shoulder muscle function before operating on the rotator cuff [10,25,39], which may take several months and prolong the treatment timeline. However, our study indicates that early surgical intervention did not hinder nerve recovery. The findings included in this study suggest that recovery generally occurred between 3 and 12 months from injury. A delay in treatment of this length may be detrimental to functional RCT recovery and could reduce the efficacy of surgery, potentially leading to irreversible degeneration, compromised shoulder function and stability, and greater complexity in future surgical interventions [25,31].

Given that nerve injuries in STT are often due to neuropraxia and the majority recover with conservative management, early surgical exploration is not recommended [7]. However, the resolution of neurologic deficits can vary in both degree and timing, creating uncertainty regarding the exact timing of surgical intervention for nerve injuries. As a result, instances of STT must be treated on a case-by-case basis. Early surgical intervention does not allow for the possibility of spontaneous nerve recovery. However, if operated on too late, nerve reconstruction is unlikely to be successful; after 12–18 months, irreversible changes in the neuromuscular junction inhibit muscle reinnervation [40]. Nerve reconstruction for closed brachial plexus injuries should be performed between 6 and 9 months after injury in those without evidence of nerve recovery [2,40]. Serial examinations and EMG studies are useful for identifying patients in whom spontaneous reinnervation is not occurring and who may benefit from surgical reconstruction [2]. The duration to neurological recovery in the published literature ranged from 3 to 12 months.

Only 4 of the 55 patients included in this review underwent nerve exploration and decompression [7,29,34]. Most patients with nerve injuries recovered spontaneously and did not require intervention. The natural history of most nerve injuries in STT appears to be spontaneous recovery and is not clearly affected by the timing of RCR. All patients offered early RCR after index injury showed good recovery of motor and nerve function at follow-up, the earliest being 2 months post-surgery. For those patients in whom surgery was deferred pending brachial plexus recovery, full recovery to baseline functional status was typically achieved by final follow-up [7,29]. These findings suggest that, while the timing of surgery remains uncertain, early RCR combined with conservative management of nerve injuries offers promising results in STT patients.

Regarding clinical decision making and management, patients presenting with STT should be evaluated for both shoulder and neurological injuries early after the injury. Providers should consider early RCR, ideally within the first 6 weeks after injury, as recovery of function is optimal during this period, and early surgical intervention did not negatively impact neurological recovery or shoulder outcomes in our review (Fig. 2). Conservative management is typically preferred for nerve injuries, as spontaneous recovery is common. If there is no significant improvement in nerve function 3 months post-injury, providers should consider further examination. In rare cases, surgical intervention for nerve injury may be considered to optimize shoulder function and prevent long-term disability.

There are limitations to this systematic review. First, only one reviewer screened articles for inclusion within each search engine, which may have introduced selection bias. This bias may theoretically have led to omitting relevant articles. However, this bias was minimized by adhering to a strict definition of STT as a combination of ASD, RCT, and nerve injury, screening multiple databases, along with the use of a second reviewer to resolve any uncertainties. Additionally, the management of STT injuries may be underreported in the literature, limiting the amount of data available for analysis. Lastly, many reported articles consist of case reports and series, introducing selection and publication bias (Table 4).

CONCLUSIONS

STT continues to be a troubling presentation of shoulder trauma. Patients undergoing surgical RCR demonstrate excellent functional and neurologic outcomes, even in the presence of brachial plexus injury. Early RCR in the setting of nerve injury did not result in inferior shoulder or neurological outcomes. Nerve injuries should be managed conservatively with watchful waiting, as most recover spontaneously. Nerve injuries that do not recover by 3 months postoperatively may need additional peripheral nerve specialist evaluation.

NOTES

Author contributions

Conceptualization: YSS. Data curation: ND, MSH. Formal analysis: ND, MSH, JEC, YSS. Investigation: MSH, LTR. Methodology: ND, MSH, JEC, YSS. Project administration: YSS. Resources: YSS. Supervision: YSS. Validation: ND, MSH, JEC, YSS. Writing – original draft: ND, MSH, ALW, WEM, JEC. Writing – review & editing: ND, MSH, ECS, ALW, WEM, JEC, YSS, LTR. All authors read and agreed to the published version of the manuscript.

Conflict of interest

None.

Funding

None.

Data availability

None.

Acknowledgments

The authors wish to thank Mariana Grohowski for editorial assistance.

Fig. 1.

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) screening summary.

Fig. 2.

Schematic summary comparing outcomes of early versus late surgical intervention in terrible triad of the shoulder. Figure created with BioRender.com; accessed on 10 January 2025.

Table 1.

Summary of STT primary literature

Study	Sample size	Results/findings
Protzuk et al. (2024) [29]	1 STT	· Case report of 60-year-old male with traumatic anterior left shoulder dislocation, irreparable RCT, and axillary nerve palsy with deltoid dysfunction
		· Lack of clinical deltoid recovery at 6 months post-injury; patient underwent axillary nerve neurolysis and radial-to-axillary reverse end-to-side transfer
		· By 10 months postoperative (16 months post-injury), near normal deltoid muscle bulk, ROM, and strength; reverse shoulder arthroplasty performed
		· At 1-year follow-up, near-full ROM and strength of shoulder (4+ strength in all planes; 150° flexion, 45° external rotation, and 110° abduction) and triceps (4+/5) achieved.
Kokkalis et al. (2023) [30]	7 STT	Case series
		· All patients underwent XR, MRI, EMG, and clinical examination.
		· Closed reduction performed on all patients, followed by early arthroscopic repair for RCTs and a conservative approach for nerve lesions
		· Arthroscopic rotator cuff repair performed by the same surgeon after a mean time of 7.9±15.8 weeks from the injury
		· All patients showed an improvement in function postoperatively; 4 of 7 patients did not fully recover.
		· Mean Constant and visual analog scale scores were improved from 15.2±2.8 to 67±16.6 and from 7.5±1 to 2.3 ±0.8, respectively.
		· Overall, time-to-surgery shorter than 4 weeks showed better results, though not statistically significant.
Du et al. (2023) [31]	1 STT	· Case report of 56-year-old male with traumatic anterior dislocation of left shoulder, fracture of the anterior inferior glenoid of the left shoulder, massive RCT of the left shoulder, and axillary nerve injury.
		· Patient underwent one-stage arthroscopic repair with strengthening exercises starting 6 weeks post-surgery; patient could exercise vigorously after 6 months.
		· Complete recovery of axillary nerve function after 6 months, and good functional recovery of shoulder joint and satisfactory ROM after 2 years. Constant score: 38–79
Marsalli et al. (2023) [32]	30 STT	· Retrospective cohort study with 30 patients with nerve injuries (35.7%); most frequent neurological injury was isolated axillary nerve damage (82.9%).
		· The study also included 84 patients with first traumatic anterior shoulder dislocation and reparable RCT.
		· All neurological injuries were initially managed without surgery.
		· Average time from injury to RCT surgery was 2.9 months. Mean follow-up was 3.9 years.
		· All nerve injuries showed at least partial recovery on sensory and motor clinical examination during follow-up without the need of further surgical treatment.
Wellington et al. (2022) [33]	1 STT	· Case report of 68-year-old male with traumatic right anterior shoulder dislocation after falling from car, which was successfully reduced at outside facility.
		· Presented to clinic 2 months post-injury: no cutaneous sensation w/n axillary nerve distribution and non-contractile deltoid. Imaging showed anterior dislocation of glenohumeral joint and complete tear of all rotator cuff muscles.
		· Patient underwent shoulder fusion, followed by 10 weeks of 2x weekly exercises starting 12 weeks after surgery.
		· At 6 months postoperative, radiographs showed excellent fusion consolidation of the glenohumeral joint. Patient was able to perform 60° of abduction, 60° of forward elevation, and activities of daily living without issue.
Le Hanneur et al. (2020) [34]	1 STT*	· One patient underwent end-to-end nerve transfer of triceps motor branches to the axillary nerve 302 days following initial injury.
		· The study also included 11 patients with shoulder dislocation and intraclavicular brachial plexus palsy.
		· At 11-month follow-up, grade-4 deltoid strength was observed.
		· Reverse shoulder arthroplasty performed at least 1 year following nerve transfer.
		· At follow-up, patient had at least 120° of active shoulder flexion and 30° external rotation.
Marsalli et al. (2020) [1]	30 STT	· Twenty-seven patients completed mean follow-up of 27 months; all nerve injuries showed evidence of reinnervation on EMG testing without the need for surgical repair of injured nerves. RCTs and distal nerve injuries correlated with better functional outcomes.
Marsalli et al. (2020) [1]	30 STT	· Despite indications for surgery in patients within 3–4 months of nerve injury, the authors state that cases can be observed longer for evidence of reinnervation and improvement in muscle function during follow-up.
Kanji et al. (2018) [16]	1 STT	· Case report of a patient with irreparable RCT who demonstrated improvement in axillary nerve palsy 6 months following injury through combination of passive ROM training and immobilization.
Kanji et al. (2018) [16]	1 STT	· Arthroscopic superior capsule reconstruction was performed which fully resolved palsy and returned normal ROM at 3 months postoperative.
Skedros et al. (2018) [23]	1 STT	· Case report of a patient with anterior shoulder dislocation, humeral fracture, and permanent axillary neuropathy due to a motocross accident, followed by subsequent rotator cuff injury 13 months after open reduction and internal fixation of the initial humeral fracture.
		· RCR occurred 2 months after the second injury and the patient was followed for 5 years.
		· Patient returned to motocross despite permanent axillary neuropathy.
Whyte and Rokito (2016) [28]	1 STT	· Case report of an anterior shoulder dislocation patient with humeral avulsion of glenohumeral ligament, RCT, and axillary nerve injury
		· Patient subsequently underwent rotator cuff and ligament tear repair.
		· Axillary nerve function fully returned with 5/5 abduction strength on MMT by 3 months following RCR.
		· Delaying care in anticipation of axillary nerve improvement would have resulted in less optimal capsule repair due to tissue retraction.
Goubier et al. (2004) [35]	1 STT	· Case report of 27-year-old male with anteromedial dislocation of left shoulder, complete motor and sensory deficit of upper limb, and distal rupture of supraspinatus and infraspinatus tendons.
		· RCT repair was performed 3 weeks following injury.
		· At 12 months postoperative, active shoulder abduction and forward elevation were 160°, and external rotation was 40°. Triceps and biceps strength were 4/5, and the patient recovered wrist and finger flexion and extension.
Simonich and Wright (2003) [7]	6 STT	· Case series of 6 patients who underwent RCT surgery an average of 5 months post-injury, with 5/6 patients demonstrating clinically significant improvement in nerve function by 12 months.
Simonich and Wright (2003) [7]	6 STT	· Recommendation for RCR as soon as diagnosis is made to minimize scarring, while avoiding nerve grafting in patients over 40 years of age where any potential benefit over observation is minimal.
Payne et al. (2002) [22]	5 STT*	· Retrospective chart review aiming to establish prevalence of STT.
		· Forty-eight Patients with shoulder trauma-associated nerve injury, 5 of which had STT.
		· No discussion of operative or nonoperative management for STT patients; authors recommended early EMG evaluation/testing in patients with persistent weakness following dislocation or rotator cuff injury due to the relatively low sensitivity of clinical examinations responsible for delays in diagnosis.
Walker and Silver (2002) [27]	1 STT	· Case report of elderly patient who elected to pursue nonoperative treatment for RCT, partial axillary nerve lesion, and brachial plexus injury.
		· While rehabilitation program resulted in improved functional ability, there was no significant recovery in shoulder abduction and biceps contraction.
		· Early EMG testing and partial nerve injury are associated with good prognosis and nerve regeneration.
Martin and Limbird (1999) [10]	1 STT	· Case report of young patient referred for clinical observation of axillary nerve function.
		· Improved axillary nerve function 4 months after injury.
		· Surgical repair of RCT resulted in functional improvement and stability of the shoulder.
		· Axillary nerve regeneration allows for repair of soft tissue injuries without complications.
Markel and Blasier (1994) [36]	1 STT	· Case report of 28-year-old male with bilateral anterior shoulder dislocations, greater tuberosity fractures, humeral fractures, and medial cord brachial plexopathy following grand mal seizure from alcohol withdrawal.
		· ORIF performed 1-week post-seizure. RCTs noted during surgery.
		· Follow-up at 7.5 months postoperative revealed 5/5 shoulder strength bilaterally and excellent ROM (flexion, right-170°, left-170°; abduction, right-170°, left-150°; external rotation, right-60°, left-50°; and internal rotation right and left to touch the T-7 vertebra).
Güven et al. (1994) [14]	1 STT	· Case report of elderly patient who underwent RCR 1 month following injury with monthly follow-up EMG testing.
		· Complete resolution of brachial plexus injury was noted postoperatively at 3 months.
		· Authors recommend early diagnosis and repair of RCTs/dislocation given exceptional prognosis for neurological recovery.
Toolanen et al. (1993) [26]	13 STT	· Sixty-five patients with anterior shoulder dislocation, 13 patients showed sonographic and EMG evidence of triad, although 6 patients reported persisting symptoms at an average follow-up of 3 years.
Toolanen et al. (1993) [26]	13 STT	· Only patients with total rotator cuff rupture were offered surgery.
Gonzalez and Lopez (1991) [37]	2 STT	· Case report of 2 patients with concurrent RCT and brachial plexus palsy associated with anterior dislocation of the shoulder
		· Patient 1 (57-year-old female): incomplete lesion of axillary and musculocutaneous nerves and complete tear of the rotator cuff. Four weeks after the injury, repair of the RC and anterior acromioplasty was performed. Three months postoperative, she had resolution of the injury (by physical examination and repeat electrodiagnostic studies). At the 2-year follow-up, she had no complaints of pain and had 130° of active abduction and forward flexion. She had returned to work as a clerk.
		· Patient 2 (66-year-old male): functional discontinuity of the RC and a complete lesion of the medial cord and an incomplete lesion of the lateral cord. Nonoperative treatment was recommended. Two years later, there was complete recovery of the lesion of the lateral cord but no recovery of the lesion of the medial cord. The patient was able to use the upper extremity in a limited capacity but had a full and painless active ROM of the shoulder.
Mehta and Kottamasu (1989) [18]	1 STT	· Case report of 53-year-old male with bilateral brachial palsy injuries and concomitant right shoulder RCT.
		· Patient underwent conservative PT/OT therapy due to suspicions of reversible neuropraxia in the context of his closed injuries.
		· Patient had significant bilateral pain and weakness at 4-month follow-up and was still in the process of recovery at time of publication.
Neviaser et al. (1988) [20]	4 STT	· Thirty-one patients with anterior shoulder dislocation and RCT, 4 patients with triad that underwent operative repair reported postoperative pain relief, yet only 1/4 experienced resolution of axillary nerve palsy and recovery of deltoid muscle function.
		· Adequate outcomes can be expected in patients with late repair of RC, but this may be influenced by surgeon expertise and prior experience.
		· Early reconstruction allows for more accurate prediction of technical problems and outcomes.
Johnson and Bayley (1982) [15]	5 STT	· Analysis of 12 patients with anterior shoulder dislocation that was accompanied by RCT, nerve injury, and/or fracture of the greater tuberosity.
		· In total, 5 shoulder dislocation patients had RCT with concomitant circumflex nerve palsy.
		· RC was surgically repaired if there was significant pain or loss of function, although surgery was delayed until deltoid function had recovered in instances of nerve palsy.
		· Of the circumflex palsy patients that had RCR, 2 had “good recovery”, 2 had “fair” recovery, and 1 had “poor recovery.”
Pasila et al. (1978) [21]	6 STT	· Prospective study of 238 patients with primary shoulder dislocation, of which 63 experienced some form of complication secondary to the dislocation.
		· There were 4 cases of shoulder dislocation with accompanying RCT and axillary nerve lesion and 2 cases of shoulder dislocation with accompanying RCT and brachial plexus lesions (n=6 STT).
		· Patient management was not well described.
Takase et al. (2014) [25]	1 STT	· Case report of 61-year-old female with triad and additional glenoid rim fracture who underwent isolated RCR 3 months after injury due to incomplete and recovering axillary nerve palsy.
		· Patient demonstrated 5/5 deltoid function on MMT just prior to surgery and full ROM 1 year after surgery.
		· Recommend early repair of RCTs in patients with incomplete axillary nerve palsy to prevent rotator cuff degeneration.
Sonnabend (1994) [24]	2 STT	· Fifty-three patients with anterior shoulder dislocation with/without fracture and neurological sequelae; 2 STT, 1 presented with brachial plexus palsy and was treated nonoperatively; the patient showed minor sensory impairment and normal motor function at 2-year follow-up.
Sonnabend (1994) [24]	2 STT	· The other patient had axillary nerve palsy and underwent RCR with subsequent pain relief, but no return of antigravity flexion/abduction nor evidence of nerve recovery at 1-year follow-up.
Kastanis et al. (2019) [17]	1 STT	· Case report of 56-year-old male with complete radial nerve palsy, RCT, and anterior shoulder dislocation who underwent conservative management using physiotherapy and passive ROM exercises due to patient preference.
Kastanis et al. (2019) [17]	1 STT	· No follow-up or final outcome was reported at the time of publication.
Miller et al. (2012) [19]	1 STT	· Case report of a 42-year-old male diver who sustained a STT injury
		· Shoulder was relocated in the ER and examination 2 weeks post-injury revealed infraspinatus and supraspinatus tears, with accompanying incomplete infraclavicular brachial plexus injury.
		· At 4 weeks post-injury, a diagnostic arthroscopy was completed then complete RCT repair was completed with supplemental postoperative physical therapy.
		· Neurologic deficits had largely resolved at 7-week postoperative follow-up.
Groh and Rockwood (1995) [13]	2 STT	· Case report of a 57-year-old female and 41-year-old male
		· The female patient responded to conservative management, with recovery of incomplete axillary nerve palsy at 6 months post-injury and return to baseline function at 3-year follow-up.
		· The male patient underwent operative RCR. Axillary nerve palsy resolved clinically and on electrodiagnostic evaluation by 3 months following surgery.

STT: terrible triad of the shoulder, RCT: rotator cuff tear, ROM: range of motion, XR: x-ray, MRI: magnetic resonance imaging, EMG: electromyography, RCR: rotator cuff repair, MMT: manual muscle testing; RC: rotator cuff, PT: physical therapy, OT: occupational therapy, ORIF: open reduction and internal fixation, ER: emergency room.

Table 2.

Timing of surgery for STT

Study	Patient No.	Duration from injury to RCT repair	RCR outcome
Protzuk et al. (2024) [29]	1	Reverse shoulder arthroplasty performed 16 months post-injury (10-month post-nerve transfer)	· At 1-year follow-up, near-full ROM and strength of shoulder (4+ strength in all planes; 150° flexion, 45° external rotation, and 110° abduction) and triceps (4+/5) achieved.
Kokkalis et al. (2023) [30]	7	Arthroscopic RCR performed by the same surgeon after a mean time of 7.9±15.8 weeks from the injury	· Mean Constant and visual analog scale scores were improved from 15.2±2.8 to 67±16.6 and from 7.5±1 to 2.3±0.8, respectively.
Kokkalis et al. (2023) [30]	7		· Overall, time-to-surgery shorter than 4 weeks showed better results, though these results were not statistically significant.
Du et al. (2023) [31]	1	One-stage arthroscopic repair performed 6 days post-injury	· Strengthening exercises started 6 weeks post-surgery.
			· Patient could exercise vigorously after 6 months.
			· Complete recovery of axillary nerve function after 6 months
			· Good functional recovery of shoulder joint and satisfactory ROM after 2 years (constant score, 38–79).
Le Hanneur et al. (2020) [34]	1	End-to-end nerve transfer of triceps motor branches to the axillary nerve 302 days following initial injury; reverse shoulder arthroplasty performed more than 1 year following nerve transfer	· At 6-week, 3-month, and 6-month follow-ups after nerve transfer, posterior cord was 4/5, 4/5, and 5/5; anteromedial cord was graded 4/5, 4/5, and 4/5; and sensitivity was graded 1/2, 2/2, and 2/2, respectively.
Le Hanneur et al. (2020) [34]	1		· Following RCR, patient had at least 120° of active shoulder flexion and 30° external rotation.
Marsalli et al. (2020) [1]	30	RCT repaired on average 2.9 months post-injury	· No cases of recurrent shoulder dislocation after surgery
			· Six patients experienced RTC retears, 5 of which underwent reoperation.
			· Those requiring only the index surgery had statistically and clinically significant improvement in preoperative assessment scores.
Kanji et al. (2018) [16]	1	Surgery occurred 6 months post-injury; surgical reconstruction of the capsule was delayed until there were signs of axillary nerve recovery, which was significant at 6-month mark	· Patient began immediate postoperative passive ROM training and shoulder girdle relaxation.
			· Hypoesthesia of axillary nerve distribution completely resolved 3 months after surgery.
			· Motor function was comparable bilaterally following active ROM exercise therapy.
Skedros et al. (2018) [23]	1	Surgery occurred 2 months post-injury	· Five years following initial motocross injury and 3 years following RCR, deltoid function had still not returned.
			· ASES score worsened from 75 to 65 at 3-year postoperative follow-up.
			· Shoulder pain persisted but did not necessitate analgesia aside from occasional NSAID use.
			· Active flexion and abduction improved to 135° with no scapular winging and a negative lift off test.
Takase et al. (2014) [25]	1	Surgery occurred 3 months post-injury; RCT repair was delayed until improvements in axillary nerve palsy	· RCR resulted in full range of motion 1 year after surgery.
Takase et al. (2014) [25]	1		· Constant score improved from 38 to 75.
Whyte and Rokito (2016) [28]	1	RC and ligament tear were surgically treated 10 days after initial injury	· Physical therapy was initiated 4 weeks after RCR. The patient demonstrated 5/5 abduction strength at 3 months.
Whyte and Rokito (2016) [28]	1		· At 9 months, the patient reported pain-free active ROM with 175° forward flexion, 55° adduction, and 110° abduction.
Miller et al. (2012) [19]	1	Diagnostic arthroscopy with subsequent RCR was completed 4 weeks post-injury	· At 7 weeks postoperatively, the patient’s motor symptoms had resolved but ulnar paresthesia persisted.
Miller et al. (2012) [19]	1		· At 13-month follow-up, the patient reported 170° of abduction, 70° external rotation, and internal rotation to T4 with no neurologic deficits.
Goubier et al. (2004) [35]	1	RCT repair was performed 3 weeks following injury.	· At 12 months postoperative, active shoulder abduction and forward elevation were 160°, and external rotation was 40°. Triceps and biceps strength were 4/5, and the patient recovered wrist and finger flexion and extension.
Simonich and Wright (2003) [7]	6	Surgical repair on average 5 months post-injury (range, 1.5–10 months)	· One patient showed no improvement in deltoid atrophy, strength, and sensation following RCR.
			· SPADI assessment at postoperative follow-up revealed good/excellent recovery in 4/6 patients.
			· No differences between the 2 patients with partial RCR and those who had a complete RCR.
			· Outcomes seemed more dependent on nerve recovery than RCR approach.
Martin and Limbird (1999) [10]	1	Surgery occurred 4 months post-injury; surgical repair of RC completed once axillary nerve function had improved, which was significant at 4-month mark.	· Full active ROM with 5/5 MMT in all muscle groups except 4/5 deltoid strength returned at 1 year postoperatively. The patient was pain-free at this follow-up period.
Güven et al. (1994) [14]	1	Surgery at 1 month post-injury	· Three-month follow-up after initial injury showed minor shoulder and elbow flexion weakness, but complete resolution of brachial plexus neuropathy.
Güven et al. (1994) [14]	1	Surgery at 1 month post-injury	· The patient could actively abduct 150° at 1 year postoperatively.
Gonzalez and Lopez (1991) [37]	1	Four weeks after injury, repair of the rotator cuff and anterior acromioplasty was performed	· Three-month postoperative patient had resolution of the injury (by physical examination and repeat electrodiagnostic studies).
Gonzalez and Lopez (1991) [37]	1		· Two-year follow-up, patient had no complaints of pain and had 130° of active abduction and forward flexion.

STT: terrible triad of the shoulder, RCT: rotator cuff tear, ROM: range of motion, RCR: rotator cuff repair, ASES: American Shoulder and Elbow Surgeons, NSAID: nonsteroidal anti-inflammatory drugs, RC: rotator cuff, SPADI: Shoulder Pain and Disability Index, MMT: manual muscle testing.

Table 3.

Patient characteristics and rotator cuff repair outcomes

Patient no.	Age (yr)/sex	Early vs. late surgery	Time to surgery	Shoulder outcome	Nerve outcome
1	76/M	Late	6 mo	Motor function was comparable bilaterally following active ROM exercise therapy.	Deltoid muscle atrophy resolved 4.5 months after surgery, indicating likely nerve recovery.
2	20/F	Late	2 mo	Active flexion and abduction improved to 135° with negative lift-off test.	Deltoid function had not recovered completely 5 years following motocross accident and 3 years after RCR.
2	20/F	Late	2 mo	ASES score worsened from 75 to 65 at 3-year follow-up.
3	16/M	Early	10 day	At 9 months postoperatively, he could perform 175° of forward flexion, 110° of abduction, 55° of adduction in external rotation, and internal rotation to T10. Negative lift-off test. Strength was symmetric bilaterally.	Axillary nerve recovered completely 3 months after surgery. Patient reported 5/5 abduction strength on manual muscle test 3 months postoperatively.
4	18/M	Late	4 mo	Full active ROM at final follow-up	One-year follow-up exam showed 4/5 deltoid strength indicating axillary nerve recovery.
5	62/M	Early	1 mo	Minor elbow flexion and shoulder weakness persisted at 1 year postoperatively, the patient could actively abduct 150° with 160° of forward elevation.	EMG showed almost complete resolution of brachial plexus injury.
5	62/M	Early	1 mo		Two months after surgery, with minimal remaining neurologic deficit.
6	61/F	Late	3 mo	Deltoid function returned 5/5 on manual muscle test prior to surgery; 1 year following repair patient reported full ROM. Constant score increased from 38 points preoperatively to 75.	Three months after injury, axillary nerve palsy recovered substantially with complete resolution of sensory disturbances.
7	42/M	Early	4 wk	At 7 weeks postoperatively, no motor deficit. At 13-month follow-up, patient could abduct 170°, internally rotate to T4, and externally rotate 70°. All motor groups returned to 5/5 strength and were symmetric bilaterally.	At 7 weeks postoperatively, intermittent ulnar paresthesia was still present, but resolved by 13-month follow-up.

ROM: range of motion, ASES: American Shoulder and Elbow Surgeons, RCR: rotator cuff repair, EMG: electromyography.

Table 4.

Risk of bias assessment

Study	1	2	3	4	5	6
Protzuk et al. (2024) [29]	High	High	Low	Low	Moderate	Moderate
Kokkalis et al. (2023) [30]	Low	High	Low	High	Low	Low
Du et al. (2023) [31]	High	High	Low	High	Low	Low
Wellington et al. (2022) [33]	High	High	Low	High	Low	Low
Marsalli et al. (2023) [32]	High	High	Low	Low	Low	Unclear
Le Hanneur et al. (2020) [34]	Low	High	Low	High	Unclear	Low
Marsalli et al. (2020) [1]	Low	Low	Low	Low	Unclear	Low
Kastanis et al. (2019) [17]	High	High	Low	High	Low	Low
Kanji et al. (2018) [16]	High	High	Low	High	Low	Low
Skedros et al. (2018) [23]	High	High	Low	High	Low	Low
Whyte and Rokito (2016) [28]	High	High	Low	High	Low	Low
Takase et al. (2014) [25]	High	High	Low	High	Low	Low
Miller et al. (2012) [19]	High	High	Low	High	Low	Low
Walker and Silver (2002) [27]	High	High	Unclear	High	Low	Low
Payne et al. (2002) [22]	Low	High	Low	Unclear	Low	Low
Goubier et al. (2004) [35]	High	High	Low	Unclear	Low	Unclear
Simonich and Wright (2003) [7]	High	High	Low	High	Low	Low
Martin and Limbird (1999) [10]	High	High	Low	High	Low	Low
Toolanen et al. (1993) [26]	Low	High	Low	High	Low	Low
Sonnabend (1994) [24]	Low	High	High	High	High	Low
Güven et al. (1994) [14]	High	High	Low	High	Low	Low
Groh and Rockwood (1995) [13]	High	High	Low	High	Low	Low
Markel and Blasier (1994) [36]	High	High	Low	Unclear	High	Unclear
Johnson and Bayley (1982) [15]	High	High	Unclear	Unclear	Low	Low
Neviaser et al. (1988) [20]	High	High	Low	High	Low	Low
Mehta and Kottamasu (1989) [18]	High	High	Unclear	Unclear	Low	Low
Gonzalez and Lopez (1991) [37]	High	High	Low	High	Low	Low
Pasila et al. (1978) [21]	Low	High	Low	High	Low	Low

1: selection of participants, 2: confounding variables, 3: measurement of exposure, 4: blinding of outcome assessment, 5: incomplete outcomes data, 6: selective outcome reporting.

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