Calcaneum-Achilles Tendon Allograft for Massive Posterosuperior Rotator Cuff Lesion With Bony Deficiency.

Dealing with massive and irreparable rotator cuff tears presents intricate challenges. Concerning elder patients, either conservative management or reverse shoulder arthroplasty could be the most appropriate treatment. On the other hand, in younger patients, there is a wide spectrum of solutions, most of them being under evaluation and not completely validated. The complexity increases when a greater tuberosity avulsion occurs at the same time. Regardless of whether surgical fixation is performed, there is a risk for bone resorption, which would result in the posterosuperior cuff's insertion spot loss. In this case, the surgeon is expected to simultaneously manage the bone loss and the tendon tear. The Calcaneum-Achilles Tendon Allograft (CalATA) therefore appears to play an interesting role due to its solid bone-tendon structure. This Technical Note aims to present the CalATA technique, which consists in both tendon and bone deficiency restoration in massive rotator cuff tears with greater tuberosity resorption.

Multidirectional instability of the shoulder: a systematic review with a novel classification.

Purpose: A variety of instabilities are grouped under multidirectional instability (MDI) of the shoulder. This makes understanding its diagnostic process, presentation and treatment difficult due to lack of evidence-based consensus. This review aims to propose a novel classification for subtypes of MDI. Methods: A systematic search was performed on PubMed Medline and Embase. A combination of the following 'MeSH' and 'non-MesH' search terms were used: (1) Glenohumeral joint[tiab] OR Glenohumeral[tiab] OR Shoulder[tiab] OR Shoulder joint[tiab] OR Shoulder[MeSH] OR Shoulder joint[MeSH], (2) Multidirectional[tiab], (3) Instability[tiab] OR Joint instability[MeSH]. Sixty-eight publications which met our criteria were included. Results: There was a high degree of heterogeneity in the definition of MDI. Thirty-one studies (46%) included a trauma etiology in the definition, while 23 studies (34%) did not. Twenty-five studies (37%) excluded patients with labral or bony injuries. Only 15 (22%) studies defined MDI as a global instability (instability in all directions), while 28 (41%) studies considered MDI to be instability in two directions, of which one had to include the inferior direction. Six (9%) studies included the presence of global ligamentous laxity as part of the definition. To improve scientific accuracy, the authors propose a novel AB classification which considers traumatic etiology and the presence of hyperlaxity when subdividing MDI. Conclusion: MDI is defined as symptomatic instability of the shoulder joint in two or more directions. A comprehensive classification system that considers predisposing trauma and the presence of hyperlaxity can provide a more precise assessment of the various existing subtypes of MDI. Level of Evidence: III.

Are Lower Passive Anterior Elevation and External Rotation at 6 Weeks Postoperatively Associated With Healing of Isolated Arthroscopic Supraspinatus Repairs?

BACKGROUND: Despite advancements in surgical technique, failure of tendon healing remains a common problem after arthroscopic rotator cuff repair (ARCR). PURPOSE/HYPOTHESIS: The purpose of this study was to examine the relationship between range of motion (ROM) recovery and healing after ARCR. It was hypothesized that an early loss of ROM would be associated with tendon healing. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: This was a retrospective comparative study of primary ARCR of isolated full-thickness supraspinatus (SSN) tendon tears. Cases were retrieved from a prospective rotator cuff repair database and divided into 2 groups based on healing (healed/nonhealed). A standardized clinical evaluation was performed before and at 6 weeks, 3 months, and 6 months after surgery. Collected data included passive and active ROM, visual analog scale for pain, and Constant score. Healing was assessed by ultrasound at 6 months. RESULTS: Of 1397 eligible ARCRs, 1207 were included. The healing rate was 86.7%. Age was higher in the nonhealed group (57.8 ± 7.9 years vs 61.6 ± 8.8 years; P < .001). Patients with healed repairs had a larger decrease in passive anterior elevation (AE) from the preoperative to the 6-week postoperative visit (-31°± 28° vs -18°± 26°; P < .001), followed by a more substantial increase throughout the remaining follow-up period (32°± 23° vs 18°± 21°; P < .001). At 6 months postoperatively, there was no difference in AE between groups (159°± 17° vs 161°± 14°; P > .999). External rotation elbow at side (ER1) and internal rotation hand in the back (IR1) followed similar courses of recovery. Passive and active ROM had a strong positive correlation at each follow-up. Age (odds ratio [OR], 1.79; 95% CI, 1.45-2.23; P < .001) and 6-week passive AE (OR, 1.33; 95% CI, 1.20-1.48; P < .001) and ER1 (OR, 1.15; 95% CI, 1.03-1.29; P = .017) were predictors for nonhealing. CONCLUSION: Lower passive AE and ER1 at 6 weeks postoperatively and younger age are associated with healing after ARCR of isolated SSN tendon tears. At 6 months postoperatively, there were no differences in ROM, regardless of tendon healing.

Studying Edema Formation After Release of the Infraspinatus Muscle as an Experimental Model of Rotator Cuff Lesions in Sheep: A Histological Analysis.

BACKGROUND: Muscle edema formation and inflammatory processes are early manifestations of acute rotator cuff lesions in sheep. Histological analysis of affected muscles revealed edema formation, inflammatory changes, and muscle tissue disruption in MRs. HYPOTHESIS: Edema contributes to inflammatory reactions and early muscle fiber degeneration before the onset of fatty infiltration. STUDY DESIGN: Controlled laboratory study. METHODS: Osteotomy of the greater tuberosity, including the insertion of the infraspinatus tendon, was performed on 14 sheep. These experimental animal models were divided into 2 groups: a nontrauma group with surgical muscle release alone (7 sheep) and a trauma group with standardized application of additional trauma to the musculotendinous unit (7 sheep). Excisional biopsy specimens of the infraspinatus muscle were taken at 0, 3, and 4 weeks. RESULTS: Edema formation was histologically demonstrated in both groups and peaked at 3 weeks. At 3 weeks, signs of muscle fiber degeneration were observed. At 4 weeks, ingrowth of loose alveolar and fibrotic tissue between fibers was detected. Fatty tissue was absent. The diameter of muscle fibers increased in both groups, albeit to a lesser degree in the trauma group, and practically normalized at 4 weeks. Immunohistology revealed an increase in macrophage types 1 and 2, as well as inflammatory mediators such as prostaglandin E2 and nuclear factor kappa-light-chain-enhancer of activated B cells. CONCLUSION: Early muscle edema and concomitant inflammation precede muscle fiber degeneration and fibrosis. Edema formation results from tendon release alone and is only slightly intensified by additional trauma. CLINICAL RELEVANCE: This study illustrates that early edema formation and inflammation elicit muscle fiber degeneration that precedes fatty infiltration. Should this phenomenon be applicable to human traumatic rotator cuff tears, then surgery should be performed as soon as possible, ideally within the first 21 days after injury.

Clinical and Radiologic Outcomes of Arthroscopic Rotator Cuff Repair in Medial Bursal-Side Fosbury Flop Tears Compared With Tendinous Avulsion Lesions.

Purpose: To determine the clinical and radiologic outcomes after surgical repair of medial bursal-side Fosbury flop rotator cuff tears compared with traditional avulsion of tendinous attachments lesions. Methods: A retrospective cohort study was performed. All patients who had undergone arthroscopic posterosuperior repair were recruited. Patients with previous shoulder rotator cuff surgery were excluded. Recruited patients were divided into 2 groups: one presenting Fosbury flop tears and the other presenting with standard avulsion lesions. Preoperative demographics such as age, gender, and arm dominance were recorded. Range of motion (ROM), visual analog scale (VAS) for pain and satisfaction, Constant score, Single Alpha-Numeric Evaluation score, and American Shoulder and Elbow Surgeons score were evaluated at 3 points in time: preoperatively, and at 6 months and minimum 1-year postoperatively. The healing of repaired cuffs was evaluated by ultrasound at 6 months. Results: Two hundred thirty-six patients were recruited, with 27 (11.4%) Fosbury flop tears and 209 (88.6%) tendon avulsions. Although there was no significant difference in gender or arm dominance between the groups, Fosbury flop tears had significantly older patients (P < .05) with a mean age 61.6 years (standard deviation 9.0), compared with tendon avulsions with a mean age of 56.1 years (standard deviation 9.1). There was no significant difference in tendon retraction between the groups. Both groups demonstrated significant improvement in ROM, visual analog scale, American Shoulder and Elbow Surgeons, Single Alpha-Numeric Evaluation, and Constant score postoperatively at 6 months and minimum 1 year. The groups demonstrated no significant difference in the ROM and clinical scores. There was a nonsignificant difference in re-tear rate of 7.4% (2/27) in Fosbury flop tears compared with 2.8% (6/209) in tendon avulsions (P = .361). Conclusions: Arthroscopic rotator cuff repair of medial bursal side Fosbury Flop rotator cuff tears results in favorable clinical and radiologic outcomes at 4 years after surgery. These outcomes are comparable with surgically repaired avulsion lesions, with an acceptable retear rate after arthroscopic repair. Level of Evidence: Level III, retrospective comparative prognostic trial.

Two-Stage Exchange Arthroplasty for Periprosthetic Reverse Shoulder Arthroplasty Infection Provides Comparable Functional Outcomes to Primary Reverse Shoulder Arthroplasty.

This study aimed to compare functional outcomes after two-stage revision reverse shoulder arthroplasty (RSA) for periprosthetic joint infection (PJI) with the results of primary RSA. Patients affected by PJI and treated by means of two-stage revision RSA were 1:1 matched with a group of patients who were treated electively with RSA without developing any complications. Out of 1477 RSAs performed between 2009 and 2021, 16 patients developed a PJI. Each matched cohort comprised 16 patients (3 females, 13 males). The mean age was 69.13 ± 5.43 years old in the PJI group and 70.28 ± 5.04 (p = 0.543) in the matched cohort. The mean follow-up was 41.23 ± 26.9 months in the PJI group and 28.5 ± 20.2 (p = 0.142) in the matched group. Only one patient showed recurrent PJI five years after revision RSA. Comparison between the PJI patients and matched patients did not show any significant differences at the latest follow-up, nor for subjective shoulder value (SSV) (p = 0.101) or Constant score (p = 0.134). Two-stage exchange RSA for PJI allows for appropriate control of the disease and good functional outcomes. Comparison with an age- and sex-matched cohort of uninfected patients showed no significant differences, thus confirming the idea that revision surgeries may lead to satisfactory functional outcomes, as expected after primary surgery.

Traumatic and Atraumatic Rotator Cuff Tears Have the Same Rates of Healing.

Background: To examine whether traumatic rotator cuff repairs (RCRs) differ in postoperative rotator cuff tendon integrity and functional outcomes from degenerative RCRs. Methods: RCRs performed by a single surgeon were retrospectively identified. The inclusion criteria were repairable Goutallier grades 0 to 2 full-thickness rotator cuff tears. Demographic and clinical data as well as radiological results were compared. A multivariate logistic regression of the of patient acceptable symptom state for American Shoulder and Elbow Surgeons (ASES) score was performed to evaluate whether the origin of tear led to a different relative risk (RR) independently from tear and surgical characteristics. Results: A total of 616 consecutive shoulders (304 traumatic and 312 degenerative) were finally included. Traumatic ruptures presented a greater distribution of male (72% vs 51%, P < .001) and younger patients (53 vs 57 years, P < .001), as well as earlier onset of symptoms (3 vs 15 months, P < .001), reduced range of motion in preoperative assessment for forward elevation (130° vs 150°, P < .001), and slightly greater preoperative ASES (46.5 ± 19.7 vs 50.0 ± 18.0, P = .022) and Constant (47.0 ± 20.2 vs 52.0 ± 18.9, P = .001) scores. Degenerative tears presented a lower proportion of grade 3 tendon coronal retraction (11% vs 18%, P = .031). Postoperative tendon integrity at 6 months was comparable for both groups, predominantly Sugaya types 1 and 2 (91% traumatic; 92% degenerative, P = .371). Both groups exhibited favorable outcomes in range of motion and postoperative functional scores at last follow-up. The multivariate regression confirmed that the tear origin was not significantly associated with patient acceptable symptom state achievement (P = .201) but rather with greater preoperative ASES score (RR, 1.01), men (RR, 1.16) and workers' compensation (RR, 0.65) (P < .05). Conclusions: Traumatic cases were frequent, involved younger patients, more frequently affected the anterior rotator cuff, and were associated with more severe tendon retraction. Traumatic and degenerative RCRs lead to comparable clinical and radiologic results. Level of Evidence: Level III, retrospective comparative study.

Hydrotherapy after Rotator Cuff Repair Improves Short-Term Functional Results Compared with Land-Based Rehabilitation When the Immobilization Period Is Longer.

Background: The evidence of hydrotherapy after rotator cuff repair (RCR) is limited as most studies either used it as an adjuvant to standard land-based therapy, or have different initiation timing. This study aimed to compare hydrotherapy and land-based therapy with varying immobilization time. Methods: Patients who underwent RCR with a 10-days or 1-month immobilization duration (early or late rehabilitation) were prospectively randomized. Results: Constant scores significantly differed at three months only, with the best score exhibited by the late hydrotherapy group (70.3 ± 8.2) followed by late land-based (61.0 ± 5.7), early hydrotherapy (55.4 ± 12.8) and early land-based (54.6 ± 13.3) groups (p < 0.001). There was a significant interaction between rehabilitation type and immobilization duration (p = 0.004). The effect of hydrotherapy compared to land-based therapy was large at three months when initiated lately only (Cohen's d, 1.3; 95%CI, 0.9-1.7). However, the relative risk (RR) of postoperative frozen shoulder or retear occurrence for late hydrotherapy was higher compared to early hydrotherapy (RR, 3.9; 95%CI, 0.5-30.0). Conclusions: Hydrotherapy was more efficient compared to land-based therapy at three months only and if initiated lately. Even though initiating hydrotherapy later brought greater constant scores at three months, it might increase the risk of frozen shoulders or retear compared to early hydrotherapy.

Functional and Radiologic Outcomes of Degenerative Versus Traumatic Full-Thickness Rotator Cuff Tears Involving the Supraspinatus Tendon.

BACKGROUND: Arthroscopic rotator cuff repair (ARCR) is among the most commonly performed orthopaedic procedures. Several factors-including age, sex, and tear severity-have been identified as predictors for outcome after repair. The influence of the tear etiology on functional and structural outcome remains controversial. PURPOSE: To investigate the influence of tear etiology (degenerative vs traumatic) on functional and structural outcomes in patients with supraspinatus tendon tears. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Patients undergoing ARCR from 19 centers were prospectively enrolled between June 2020 and November 2021. Full-thickness, nonmassive tears involving the supraspinatus tendon were included. Tears were classified as degenerative (chronic shoulder pain, no history of trauma) or traumatic (acute, traumatic onset, no previous shoulder pain). Range of motion, strength, the Subjective Shoulder Value, the Oxford Shoulder Score (OSS), and the Constant-Murley Score (CMS) were assessed before (baseline) and 6 and 12 months after ARCR. The Subjective Shoulder Value and the OSS were also determined at the 24-month follow-up. Repair integrity after 12 months was documented, as well as additional surgeries up to the 24-month follow-up. Tear groups were compared using mixed models adjusted for potential confounding effects. RESULTS: From a cohort of 973 consecutive patients, 421 patients (degenerative tear, n = 230; traumatic tear, n = 191) met the inclusion criteria. The traumatic tear group had lower mean baseline OSS and CMS scores but significantly greater score changes 12 months after ARCR (OSS, 18 [SD, 8]; CMS, 34 [SD,18] vs degenerative: OSS, 15 [SD, 8]; CMS, 22 [SD, 15]) (P < .001) and significantly higher 12-month overall scores (OSS, 44 [SD, 5]; CMS, 79 [SD, 9] vs degenerative: OSS, 42 [SD, 7]; CMS, 76 [SD, 12]) (P≤ .006). At the 24-month follow-up, neither the OSS (degenerative, 44 [SD, 6]; traumatic, 45 [SD, 6]; P = .346) nor the rates of repair failure (degenerative, 14 [6.1%]; traumatic 12 [6.3%]; P = .934) and additional surgeries (7 [3%]; 7 [3.7%]; P = .723) differed between groups. CONCLUSION: Patients with degenerative and traumatic full-thickness supraspinatus tendon tears who had ARCR show satisfactory short-term functional results. Although patients with traumatic tears have lower baseline functional scores, they rehabilitate over time and show comparable clinical results 1 year after ARCR. Similarly, degenerative and traumatic rotator cuff tears show comparable structural outcomes, which suggests that degenerated tendons retain healing potential.

Preoperative diagnosis and rotator cuff status impact functional internal rotation following reverse shoulder arthroplasty.

PURPOSE: This study aimed to evaluate whether functional internal rotation (fIR) following reverse shoulder arthroplasty (RSA) differs based on diagnosis of either: primary osteoarthritis (OA) with intact rotator cuff, massive irreparable rotator cuff tear (MICT) or cuff tear arthropathy (CTA). METHODS: A retrospective review was carried out on RSAs performed by a single surgeon with the same implant over a 5-year period. Minimum 2-year follow-up was available in 235 patients; 139 (59.1%) were female, and the mean patient age was 72 ± 8 years. Additional clinical evaluation included the Subjective Shoulder Value and Constant score. Postoperative internal rotation was categorized as type I: hand to the buttock or hip; type II: hand to the lower lumbar region; or type III: smooth motion to at least the upper lumbar region. Type I was considered "nonfunctional" internal rotation, and type II and III were fIR. RESULTS: Preoperatively, internal rotation was classified as type I in 60 patients (25.5%), type II in 114 (48.5%), and type III in 62 (26%). Postoperatively, internal rotation was classified as type I in 70 patients (30%), type II in 86 (36%), and type III in 79 (34%). Compared with preoperative status, fIR improved significantly in OA patients (P < .001), with 49 (52.6%) classified as type II or III postoperatively. In CTA patients, there was no significant change (P = .352). In patients with MICTs, there was a significant loss in fIR postoperatively (P = .003), with 25 patients (30.8%) deteriorating to type I after having either type II or III preoperatively, and only 5 patients (6.1%) improving to either type II or III. CONCLUSIONS: Patients who undergo RSA for primary OA have a better chance of postoperative fIR improvement. A decrease in fIR is common after RSA for MICTs.

Superior capsular reconstruction for irreparable posterosuperior rotator cuff tears.

Although the superior portion of the shoulder joint capsule is a clearly distinct structure, its ability to prevent vertical humeral head translation in irreparable rotator cuff tears remains controversial. The clinical results of superior capsule reconstruction (SCR) in this context are satisfactory but the radiological outcomes are poor in up to two-thirds of patients. Moreover, there is no proof that SCR is more beneficial than simply doing a subacromial debridement, a partial repair or a tenotomy of the long head of biceps. Furthermore, graft healing is not predictive of success. Given the lack of comparative studies with high level of evidence (level 1 or 2), we cannot conclude that this surgical technique (and its many variants) has a place in our treatment paradigm. Also, it seems that xenografts are no longer being used given the high rate of structural failure seen on MRI and the large number of complications. If the long head of biceps tendon is still intact at the time of surgery, it is a feasible option for SCR given the reasonable cost and minimal complications. If it is not - but the subscapularis tendon is intact or repairable - an allograft or a non-local autograft should be considered, despite its unpredictable clinical results. Surgeons should inform patients of the high rate of radiological repair failure and the worse results if a reverse shoulder arthroplasty should be needed subsequently. Level of evidence: 4.

The role of bone morphology of the greater tuberosity and lateral acromion on subacromial space during scaption: a three-dimensional dynamic simulation analysis.

BACKGROUND: The bone morphology of the greater tuberosity and lateral acromion plays a central role in subacromial impingement syndrome. The critical shoulder angle (CSA) and greater tuberosity angle (GTA) are two-dimensional measurement parameters that have been validated to evaluate it radiologically. These markers are, however, static and don't consider the dynamic effect of glenohumeral motion. OBJECTIVES: This study aimed to better understand the biomechanics in subacromial impingement with a dynamic simulation based on a validated 3D biomechanical model coupling joint kinematics and 3D reconstructed computed tomography. STUDY DESIGN & METHODS: Sixty-one patients were included in this study: a case group of 44 patients with degenerative rotator cuff tears involving only the supraspinatus, and a control group of 17 without a rotator cuff tear. Patients with previous surgeries, traumatic cuff tears, and cuff tear arthropathy were excluded. CSA, GTA, and impingement-free range of motion (IF-ROM) of the glenohumeral joint in scaption were calculated. Correlation tests were used to determine the relationship between ROM and CSA, GTA, and combined CSA and GTA values. RESULTS: CSA and GTA were significantly higher in the rotator cuff tear group (p = 0.001 and < 0.001), while IF-ROM was significantly higher in the control group (p = 0.001). There was no overall correlation between CSA and GTA (R = 0.02, p = 0.8). Individual correlation between both angles with IF-ROM was negatively weak for CSA (R = -0.4, p < 0.001) and negatively moderate for GTA and IF-ROM (R = -0.5, p < 0.001). However, combining both angles resulted in a negatively high correlation with IF-ROM (R = -0.7, p < 0.001). CONCLUSION: Subacromial space narrowing during scaption is highly correlated to the cumulative values of GTA and CSA. These findings suggest that the combined bony morphology of the lateral acromion and greater tuberosity plays an important role in subacromial impingement. LEVEL OF EVIDENCE: III.

Long Head of the Biceps Pediculated Autograft Augmentation of Arthroscopic Subscapularis Repair.

Subscapularis (SSc) repairs are not free of failure and continues to pose a challenging problem. Although various biological and structural augmentation methods are available for the posterosuperior rotator cuff, few options have been explored for the anterior one. In the Technical Note, we describe an all-arthroscopic technique in which we use the long head of the biceps tendon (LHBT) as a pediculated autograft to reinforce an SSc repair. After SSc repair and LHBT tenodesis, the intra-articular portion of the LHBT is placed on the upper part of the SSc tendon at the rotator interval. Repurposing the otherwise-discarded tendon brings several biological and mechanical advantages at a lower cost without donor-site morbidity.

Editorial Commentary: Shoulder Arthroscopic Dynamic Anterior Stabilization Is Effective for Anteroinferior Shoulder Instability With Limited Anterior Bone Loss.

Shoulder dynamic anterior stabilization (DAS) is an efficient and well-established glenohumeral stabilization technique, offering an arthroscopic alternative to Latarjet and glenoid reconstruction with distal tibial allograft or the iliac crest autograft. DAS is essentially an augmented Bankart procedure and can be performed using transfer of either the long head of the biceps tendon or the conjoined tendon. Both result in similar and acceptable rates of recurrences, complications, return to sport, and subjective shoulder function. However, the effectiveness of Bankart repair on shoulder stability decreases significantly over time, so long-term follow-up evaluations of DAS are required. The best indication for DAS may be anteroinferior shoulder instability with limited anterior bone loss.

Massive Irreparable Rotator Cuff Tears: Which Patients Will Benefit from Physiotherapy Exercise Programs? A Narrative Review.

Massive irreparable rotator cuff tears can cause significant shoulder pain, disability and reduction in quality of life. Treatment approaches can be operative or non-operative. Operative approaches include reverse total shoulder arthroplasty, arthroscopic debridement, partial rotator cuff repair, subacromial balloon spacers, superior capsule reconstruction, and tendon transfer procedures. Non-operative approaches include physiotherapy exercise programs and corticosteroid injections. There are no randomized controlled trials comparing the different treatment approaches. It is therefore challenging for clinicians to advise patients on what is their best treatment pathway. Physiotherapy exercise programs are less expensive and have lower risks for patients than surgical approaches. However, the success of physiotherapy in patients with massive irreparable rotator cuff tears is highly variable with published success rates of 32-96%. Several cohort studies have sought to identify if certain factors are predictive of success with physiotherapy. Several biomechanical factors were identified as possibly being related to a successful or unsuccessful outcome following physiotherapy, with complete tear of subscapularis demonstrating the strongest evidence. However, there were no appropriately designed prognostic studies. There has been a strong emphasis on biomechanical factors. Other domains such as psychosocial factors, which are important in similar patient populations, have not been explored. We recommend that further research is needed in this area and should include randomized controlled trials comparing treatment approaches and longitudinal prospective prognostic studies to identify predictors of treatment success.

Muscle Edema of Retraction and Pseudo-Fatty Infiltration After Traumatic Rotator Cuff Tears: An Experimental Model in Sheep.

Background: Traumatic rotator cuff tears can result in retraction of the tendon and may be associated with muscle edema, which may be confused with fatty infiltration as seen on magnetic resonance imaging (MRI). Purpose: To describe the characteristics of a type of edema associated with acute retraction of the rotator cuff tendon (termed "edema of retraction") and to highlight the risk of mistaking it with pseudo-fatty infiltration of the rotator cuff muscle. Study Design: Descriptive laboratory study. Methods: A total of 12 alpine sheep were used for analysis. On the right shoulder, osteotomy of the greater tuberosity was performed to release the infraspinatus tendon; the contralateral limb acted as the control. MRI was performed immediately after surgery (time zero) and at 2 and 4 weeks postoperatively. T1-weighted, T2-weighted, and Dixon pure-fat sequences were reviewed for hyperintense signals. Results: Edema of retraction resulted in hyperintense signals around or within the retracted rotator cuff muscle on both T1- and T2-weighted imaging, but there was an absence of hyperintense signals on Dixon pure-fat imaging. This represented pseudo-fatty infiltration. Edema of retraction created a characteristic "ground glass" appearance of the muscle on T1-weighted sequences and was often found in either the perimuscular or intramuscular location of the rotator cuff muscle. Compared to time zero values, a decrease in the percentage of fatty infiltration was observed at 4 weeks postoperatively (16.5% ± 4.0% vs 13.8% ± 2.9%, respectively; P < .005). Conclusion: The location of edema of retraction was often peri- or intramuscular. Edema of retraction presented as a characteristic "ground glass" appearance of the muscle on T1-weighted sequences and led to a decrease in the fat percentage because of a dilution effect. Clinical Relevance: Physicians should be aware that this edema can result in a form of pseudo-fatty infiltration, as it is associated with hyperintense signals on both T1- and T2-weighted sequences, and it can be mistaken for fatty infiltration.

Comparison of suture-bridge and independent double-row techniques for medium to massive posterosuperior cuff tears: a two-year retrospective study.

BACKGROUND: Transosseous-equivalent suture-bridge (TOE-SB) and independent double-row (IDR) repair techniques were developed to treat rotator cuff tears. The study was designed to prove that both TOE-SB and IDR techniques provided comparable clinical results and retear rate for medium to massive posterosuperior rotator cuff tears, while the surgical time and number of suture anchor used were less in the IDR group. STUDY DESIGN: Level of evidence: level III, Retrospective comparative study. METHODS: Patients with medium to massive posterosuperior rotator cuff tears receiving arthroscopic TOE-SB and IDR between November 2016 to October 2019 were retrospectively enrolled. All patients were confirmed to have grade ≤ 2 fatty infiltration in the muscles of the torn tendons. Revision, concomitant subscapularis tear, acromiohumeral distance < 7 mm, glenohumeral osteoarthritis, partial repair, incomplete repair, partial thickness, or irreparable posterosuperior cuff tear were excluded. Surgical time, number of suture anchor used for the surgery, pre-operative, and post-operative clinical scores such as Constant-Murley score, subjective shoulder value (SSV), and visual analog scale (VAS) were compared. The retear rates between groups were evaluated by ultrasound. RESULTS: Thirty-five IDR and thirty-five TOE-SB repairs were enrolled. The IDR technique required much fewer anchors than TOE-SB did to complete the cuff repair. The mean operation time in IDR and TOE-SB group were 86(18.23), and 114(18.7) (min), respectively (P <  0.01). The mean number of anchors used to complete the cuff repair was 2(0.17) in IDR and 3(0.61) in TOE-SB (P <  0.01). The Constant-Murley score improved from 34.9 ± 6.6 to 80.6 ± 9.4 in the IDR group, and 37.4 ± 6 to 81.9 ± 4.6 in the TOE-SB group (both P <  0.001). SSV improved from 24.6 ± 9.6 to 79.3 ± 10.6 in the IDR, and 27.9 ± 9 to 82.9 ± 6.9 in the TOE-SB group (both P <  0.001). VAS improved from 7.9 ± 0.6 to 1.5 ± 0.7 in the IDR, and 8 ± 0.5 to 1.3 ± 0.6 in the TOE-SB group (both P <  0.001) at final follow-up. No significant difference was found between the retear rates (14.3% in the IDR vs. 17.1% in the TOE-SB, respectively) in the 2-year follow-up. CONCLUSIONS: Both IDR and TOE-SB group provided comparable clinical results and retear rates for medium to massive posterosuperior rotator cuff tears. The surgical time and number of anchors used were less in the IDR group than in the TOE-SB group.

Stemless reverse shoulder arthroplasty: clinical and radiologic outcomes with minimum 2 years' follow-up.

BACKGROUND: Recently, a stemless reverse shoulder arthroplasty (RSA) design was developed to preserve bone stock. Clinical and radiologic studies of this design in larger cohorts with >100 patients are not frequent. The purpose of this study was to present the clinical and radiologic results of a newly developed stemless RSA implant. The hypothesis was that this design would provide similar clinical and radiologic results to other stemless implants, as well as stemmed implants. METHODS: Between September 2015 and December 2019, all patients who underwent primary RSA with a stemless Easytech prosthesis were considered eligible for inclusion in this prospective multicenter study. The minimum follow-up period was 2 years. Clinical outcomes consisted of the Constant score, adjusted Constant score, QuickDASH (short version of Disabilities of the Arm, Shoulder and Hand questionnaire) score, Subjective Shoulder Value, and American Shoulder and Elbow Surgeons shoulder score. Radiographic parameters included radiolucency, loosening, scapular notching, and specific geometric parameters. RESULTS: Stemless RSA was performed in 115 patients (61 women and 54 men) at 6 different clinical centers. The average age at the time of surgery was 68.7 years. The average Constant score was 32.5 preoperatively and showed significant improvement to 61.8 at latest follow-up (P < .001). The Subjective Shoulder Value also demonstrated significant improvement postoperatively (from 27.0 to 77.5, P < .001). Scapular notching was observed in 28 patients (24.3%); humeral loosening, 5 (4.3%); and glenoid loosening, 4 (3.5%). The total complication rate was 17.4%. Eight patients (4 women and 4 men) underwent implant revision. CONCLUSION: The clinical outcomes of the examined stemless RSA seem to be comparable to those of other humeral designs; however, the complication and revision rates are higher than those of historical controls. Surgeons should proceed with caution when using this implant until longer-term follow-up data are available.

Developing a machine learning algorithm to predict probability of retear and functional outcomes in patients undergoing rotator cuff repair surgery: protocol for a retrospective, multicentre study.

INTRODUCTION: The effectiveness of rotator cuff tear repair surgery is influenced by multiple patient-related, pathology-centred and technical factors, which is thought to contribute to the reported retear rates between 17% and 94%. Adequate patient selection is thought to be essential in reaching satisfactory results. However, no clear consensus has been reached on which factors are most predictive of successful surgery. A clinical decision tool that encompassed all aspects is still to be made. Artificial intelligence (AI) and machine learning algorithms use complex self-learning models that can be used to make patient-specific decision-making tools. The aim of this study is to develop and train an algorithm that can be used as an online available clinical prediction tool, to predict the risk of retear in patients undergoing rotator cuff repair. METHODS AND ANALYSIS: This is a retrospective, multicentre, cohort study using pooled individual patient data from multiple studies of patients who have undergone rotator cuff repair and were evaluated by advanced imaging for healing at a minimum of 6 months after surgery. This study consists of two parts. Part one: collecting all potential factors that might influence retear risks from retrospective multicentre data, aiming to include more than 1000 patients worldwide. Part two: combining all influencing factors into a model that can clinically be used as a prediction tool using machine learning. ETHICS AND DISSEMINATION: For safe multicentre data exchange and analysis, our Machine Learning Consortium adheres to the WHO regulation 'Policy on Use and Sharing of Data Collected by WHO in Member States Outside the Context of Public Health Emergencies'. The study results will be disseminated through publication in a peer-reviewed journal. Institutional Review Board approval does not apply to the current study protocol.