Preoperative Fatty Infiltration Research Articles

Subscapularis Repair in Reverse Total Shoulder Arthroplasty: Differences in Outcomes Based on Preoperative Quality of Subscapularis Tendon.

This study examines the influence of preoperative fatty infiltration (FI) of the subscapularis tendon (SBS) on outcomes following reverse total shoulder arthroplasty (rTSA) with SBS repair. A cohort of 161 rTSA patients with SBS repair, followed for a mean of 45.3months, was divided into three groups based on FI: Group A (intact upper and lower portions, n = 85), Group B (intact lower portions, n = 44), and Group C (fatty infiltrated in both portions, n = 32). The mean age was 74.5years (range: 65-95). Preoperative FI displayed significant disparity among the groups: Group A (1.18 ± 0.60), Group B (2.95 ± 0.56), and Group C (4.0 ± 0.00) (p < .001). Group A exhibited a more positive trend in activities of daily living, particularly in toileting ability (81% in Group A, 68% in Group B, and 72% in Group C), although without statistical significance (p = 0.220). Complication rates varied: Group A had seven acromial fractures (8%), three cases of instability (3%), and six instances of scapular notching (7%). Group B experienced four acromial fractures (9%) and four cases of scapular notching (9%), while Group C had only one case of scapular notching (3%) (p = 0.733). In cases characterized by favorable preoperative SBS quality, there was an elevation in functional internal rotation (IR) post-surgery, accompanied by an increased incidence of postoperative complications. Hence, careful consideration is advised when determining the necessity for SBS repair. Level III, retrospective comparative study.

Preoperative fatty infiltration of paraspinal muscles assessed by MRI is associated with less improvement of leg pain 2 years after surgery for lumbar spinal stenosis

PurposeFatty infiltration (FI) of the paraspinal muscles may associate with pain and surgical complications in patients with lumbar spinal stenosis (LSS). We evaluated the prognostic influence of MRI-assessed paraspinal muscles’ FI on pain or disability 2 years after surgery for LSS.MethodsA muscle fat index (MFI) was calculated (by dividing signal intensity of psoas to multifidus and erector spinae) on preoperative axial T2-weighted MRI of patients with LSS. Pain and disability 2 years after surgery were assessed using the Oswestry disability index, the Zurich claudication questionnaire and numeric rating scales for leg and back pain. Multivariate linear and logistic regression analyses (adjusted for preoperative outcome scores, age, body mass index, sex, smoking status, grade of spinal stenosis, disc degeneration and facet joint osteoarthritis) were used to assess the associations between MFI and patient-reported clinical outcomes. In the logistic regression models, odds ratios (OR) and 95% confidence intervals (CI) were calculated for associations between the MFI and ≥ 30% improvement of the outcomes (dichotomised into yes/no).ResultsA total of 243 patients were evaluated (mean age 66.6 ± 8.5 years), 49% females (119). Preoperative MFI and postoperative leg pain were significantly associated, both with leg pain as continuous (coefficient − 3.20, 95% CI − 5.61, − 0.80) and dichotomised (OR 1.51, 95% CI 1.17, 1.95) scores. Associations between the MFI and the other outcome measures were not statistically significant.ConclusionPreoperative FI of the paraspinal muscles on MRI showed statistically significant association with postoperative NRS leg pain but not with ODI or ZCQ.

Suture Contamination During Arthroscopic Rotator Cuff Repair Is Associated With Significantly Higher Retear Rates in Magnetic Resonance Imaging: A Matched-Pair Analysis

PurposeTo evaluate the correlation between suture contamination and rotator cuff tendon retear after arthroscopic rotator cuff repair. MethodsPatients undergoing primary arthroscopic rotator cuff repair from April 1st, 2020 to September 30th, 2022 were enrolled. Those younger than 18 years, with a history of prior shoulder surgeries or shoulder infection episodes, or who declined participation, were excluded. A 5 cm section of the first-cut suture, originating from the anchor eyelet ends, in each rotator cuff repair surgery was subjected to bacteria culture and polymerase chain reaction (PCR) analysis. Patients with positive culture findings were matched 1:1 to those with negative culture reports based on age, sex, tear size as well as involved tendons, preoperative fatty infiltration grade (Goutallier grade) and preoperative muscle atrophy grade (Warner score). Postoperative rotator cuff tendon retear assessments were conducted at the 6-month mark using the Sugaya classification via magnetic resonance imaging. The Wilcoxon signed-rank test was used for matched-pair comparisons between the groups. ResultsA total of 141 patients (60 males and 81 females) with a mean age of 61.0 ± 8 years were finally enrolled. Twenty-six patients (18 males and 8 females) had a positive culture, while 115 patients (42 males and 73 females) had a negative culture. After the propensity score matching process, 24 culture-negative patients (16 males and 8 females) were selected as the culture-negative group. Age, fatty infiltration grade, and muscle atrophy grade were not significantly different between matched groups. The retear grade in the culture-positive group was found to be significantly higher than that in the culture-negative group (P = 0.020) under the matched-pair comparison. C. acnes. was the most prevalent bacterial species responsible for suture contamination. ConclusionsThe matched-pair analysis revealed that the presence of bacterial contamination on sutures was associated with a higher risk of retear in MRI following arthroscopic rotator cuff repair.

Does the Fatty Infiltration Influence the Re-tear Rate and Functional Outcome After Rotator Cuff Repair? A Systematic Review and Meta-analysis.

Fatty infiltration (FI) of the rotator cuff muscles occurs after rotator cuff tears (RCTs), which may affect the outcome of the repair procedure. This study aimed to determine the relationship between preoperative FI and the rate of re-tear and functional outcomes after rotator cuff repair. Computerized databases, including PubMed, EMBASE, Web of Science, and Cochrane Library database were searched for studies published from the inception date to January 2022. Two reviewers independently screened the titles and abstracts using prespecified criteria. Articles were included if they clearly stated the effect of varying degrees of FI on the outcome after shoulder cuff repair. Comparison was performed by different degrees of FI analysis: no FI is grade 0-1, FI is grade 2 and above. Statistical analysis was performed using Review Manager 5.4.1 software. A total of 16 articles involving 1383 patients from 8 countries were included. The follow-up period ranged from 8 to 121months. In terms of re-tear rate: patients with preoperative FI had significantly higher rates of re-tear compared with patients without FI (OR 4.60, 95% CI 2.22-9.54, p < 0.0001), supraspinatus FI VS no FI (OR 2.06, 95% CI 1.00-4.24, p = 0.05), infraspinatus FI VS no FI (OR 2.42, 95% CI 1.19-4.91, p = 0.01). In terms of functional scoring: patients without FI had higher postoperative Constant-Murley (Constant) scores than those with FI (MD -5.06, 95% CI -9.40 to -0.72, p = 0.02), there was no clear evidence that preoperative FI was related to postoperative American Society of shoulder and elbow physicians scores and the University of California at Los Angeles scores and range of motion. FI after RCTs significantly increases the risk of postoperative re-tear and leads to worse functional scores, especially FI of the infraspinatus muscle. However, FI does not seem to reduce postoperative range of motion. The online version contains supplementary material available at 10.1007/s43465-022-00807-0.

Association between preoperative fatty infiltration of the paraspinal muscles and persistent leg pain after surgery for LSS

Association between preoperative fatty infiltration of the paraspinal muscles and persistent leg pain after surgery for LSS

High Acromial Slope and Low Acromiohumeral Distance Increase the Risk of Retear of the Supraspinatus Tendon After Repair.

High Acromial Slope and Low Acromiohumeral Distance Increase the Risk of Retear of the Supraspinatus Tendon After Repair.

Can Lateralization of Reverse Shoulder Arthroplasty Improve Active External Rotation in Patients with Preoperative Fatty Infiltration of the Infraspinatus and Teres Minor?

(1) Background: Postoperative recovery of external rotation after reverse shoulder arthroplasty (RSA) has been reported despite nonfunctional external rotator muscles. Thus, this study aimed to clinically determine the ideal prosthetic design allowing external rotation recovery in such a cohort. (2) Methods: A monocentric comparative study was retrospectively performed on patients who had primary RSA between June 2013 and February 2018 with a significant preoperative fatty infiltration of the infraspinatus and teres minor. Two groups were formed with patients with a lateral humerus/lateral glenoid 145° onlay RSA—the onlay group (OG), and a medial humerus/lateral glenoid 155° inlay RSA—the inlay group (IG). Patients were matched 1:1 by age, gender, indication, preoperative range of motion (ROM), and Constant score. The ROM and Constant scores were assessed preoperatively and at a minimum follow-up of two years. (3) Results: Forty-seven patients have been included (23 in OG and 24 in IG). Postoperative external rotation increased significantly in the OG only (p = 0.049), and its postoperative value was significantly greater than that of the IG by 11.1° (p = 0.028). (4) Conclusion: The use of a lateralized humeral stem with a low neck-shaft angle resulted in significantly improved external rotation compared to a medialized humeral 155° stem, even in cases of severe fatty infiltration of the infraspinatus and teres minor. Humeral lateralization and a low neck-shaft angle should be favored when planning an RSA in a patient without a functional posterior rotator cuff.

Long-term results of partial repair for irreparable rotator cuff tear.

BackgroundThe irreparability of rotator cuff repair is generally determined during surgery. We have been performing partial repairs for rotator cuff tears that are deemed irreparable with primary repair. The aim of this study is to report, for the first time, the long-term postoperative outcome of our partial repair method and to clarify the criteria for the irreparability of primary repair.MethodsThe UCLA score, radiographic findings, and magnetic resonance imaging findings of 156 shoulders that underwent rotator cuff repair (primary repair, 126 shoulders; partial repair, 30 shoulders) were retrospectively evaluated at preoperative and >10-year postoperative follow-up (mean evaluation time, 11.5 ± 1.0 years). Osteoarthritic (OA) changes were evaluated by radiographic findings, and the cuff integrity (Sugaya classification) and fatty infiltration (Goutallier classification) were evaluated by magnetic resonance imaging findings. These evaluations were compared between a primary repair group and partial repair group.ResultsAlthough no significant difference was observed between preoperative and postoperative findings for the UCLA score, the strength of forward flexion was significantly lower at 10 years postoperatively in the partial repair group. Preoperative image evaluation showed no significant difference in OA changes between the 2 groups; however, fatty infiltration showed significantly greater progression in the partial repair group than the primary repair group. At >10-year postoperative follow-up, the OA changes, cuff integrity, and fatty infiltration showed significantly greater progression in the partial repair group compared to the primary repair group. Although the long-term outcome of the partial repair group was inferior to that of the primary repair group in imaging evaluations, good functional outcome of the shoulder joint was maintained.ConclusionOur results suggested that partial repair could be an effective treatment option for irreparable rotator cuff tear. In terms of the feasibility of primary repair, the cutoff value for preoperative fatty infiltration was stage 2; thus, we believe that primary repair should be performed for cases with stage 2 fatty infiltration or lower, and partial repair should be performed for cases with stage 3 fatty infiltration or higher. However, manual workers and athletes with stage 3 fatty infiltration or higher should be advised in advance that mild muscle weakness may remain after surgery.

Preoperative Fatty Infiltration of the Teres Minor Negatively Affects Postoperative Outcomes in Patients With Rotator Cuff Pathology.

Background:The teres minor is a critical component of the rotator cuff and serves as one of the few external rotators of the humerus. Information is lacking regarding the effect of teres minor atrophy in isolation and in the setting of concomitant full-thickness rotator cuff tears on outcomes in patients undergoing rotator cuff surgery.Purpose:To investigate the effect of preoperative teres minor fatty infiltration on postoperative clinical outcomes in patients with and without full-thickness rotator cuff pathology.Study Design:Cohort study; Level of evidence, 3.Methods:A retrospective review of patients undergoing primary arthroscopic shoulder surgery between 2014 and 2016 was performed. Preoperative magnetic resonance imaging was used to determine fatty infiltration for each rotator cuff muscle using the modified Goutallier classification. American Shoulder and Elbow Surgeons (ASES) as well as the shortened version of Disabilities of the Arm, Shoulder and Hand (QuickDASH) scores were obtained preoperatively and during follow-up. Exclusion criteria included prior surgery on the ipsilateral shoulder or a diagnosis of inflammatory arthropathy. For analysis, patients were dichotomized to grade 0 or grade 1-4 atrophy of the teres minor as well as to full-thickness or partial-thickness rotator cuff pathology.Results:A total of 36 of 47 (76.6%) patients (mean age, 63 years; range, 45-76 years) were available for postoperative follow-up at a mean of 40 months (range, 30-48 months). Postoperative ASES score was significantly higher and QuickDASH score was significantly lower among all patients in the grade 0 group compared with the grade 1-4 group. Postoperative ASES and QuickDASH scores were not significantly different in patients with partial-thickness rotator cuff tears at any time point. However, the postoperative ASES score was significantly higher and QuickDASH score was significantly lower in the grade 0 versus grade 1-4 group for patients with full-thickness rotator cuff pathology.Conclusion:Preoperative teres minor atrophy in patients undergoing surgery for rotator cuff pathology may impair postoperative clinical outcomes, especially in patients with full-thickness tears.

Postoperative rotator cuff integrity: can we consider type 3 Sugaya classification as retear?

Sugaya classification is a widely accepted classification system that is used to analyze postoperative rotator cuff tendon integrity. However, there are inconsistencies in the literature as to whether type 3 Sugayashould be considered as a retear or healed tendon. We aimed to show that type 3 Sugaya is not a retear by comparing the long-term supraspinatus and infraspinatus muscle degenerationand the functional outcomes of type 3 with those of type 4 and 5 Sugaya. We hypothesized that the clinical course of type 3 Sugaya would be different from type 4 or 5 Sugaya. The study was a retrospective multicenter review of all the rotator cuff repair done in 2003-2004. We included all the patients who had undergone supraspinatus repair with 10-year follow-up (magnetic resonance imaging done with full functional assessment). Data collection included pre- and postoperative supraspinatus and infraspinatus fatty infiltration, supraspinatus muscle atrophy, and Constant score with a separate analysis of its Strength subsection. Supraspinatus tendon integrity at 10-year follow-up was determined according to Sugaya classification. The patients were divided into 2 groups: type 3 Sugaya and type 4 and 5 Sugaya. Statistical comparison was done between the groups. There was no significant difference in the preoperative fatty infiltration of the supraspinatus and infraspinatus, supraspinatus muscle atrophy, and Constant score between the 2 groups. However, type 3 Sugaya patients had significantly better scores in the preoperative Strength subsection. Postoperatively, type 3 Sugaya patients showed significantly lesser fatty infiltration of the supraspinatus and infraspinatus, lesser supraspinatus muscle atrophy, and higher Constant score compared with type 4 and 5 Sugaya(P < .001). Patients with type 3 Sugaya supraspinatus tendon exhibited lesser muscle degeneration in the supraspinatus and infraspinatusand performed better in functional assessment compared with type 4 and 5 Sugaya patients. We inferred that type 3 Sugaya should not be considered as a retear.

Association of Preoperative Gluteal Muscle Fatty Infiltration With Patient Outcomes in Women After Hip Abductor Tendon Repair Augmented With LARS

Background: Hip abductor tendon repair has demonstrated encouraging outcomes. The influence of fatty infiltration (FI) on outcome has not been explored. Purpose: To investigate the association between preoperative hip abductor FI and clinical outcome after hip abductor tendon repair. Study Design: Case series; Level of evidence, 4. Methods: A total of 84 women underwent hip abductor tendon repair. The mean age was 64.6 years (range, 43-84 years); body mass index, 27.7 (range, 20.0-40.2); and duration of symptoms, 3.4 years (range, 6 months–20 years). The 6-minute walk test, isometric hip abduction strength assessment, and patient-reported outcome measures, including the Harris Hip Score and Oxford Hip Score, were completed presurgery and 2 years after surgery. Patient satisfaction and perceived improvement were assessed 2 years after surgery. All patients underwent preoperative magnetic resonance imaging on the affected hip, and the Goutallier system was used to grade the degree of FI in the anterior, middle, and posterior thirds of the gluteus medius and minimus on a 0-4 ordinal scale. A single FI score for the gluteus medius and minimus was calculated, as was a combined FI score. Results: All clinical scores significantly improved over time (P < .001). Preoperatively, FI was more severe in the gluteus minimus, with the most severe FI (grades 2-4) demonstrated in the middle (n = 56, 66.7%) and anterior (n = 17, 20.2%) portions of the gluteus minimus and the middle (n = 27, 32.1%) and anterior (n = 12, 14.3%) portions of the gluteus medius. Older age was associated with greater FI (combined FI score: r = 0.529, P < .001), although duration of symptoms (r = 0.035, P = .753) and body mass index (r = 0.089, P = .464) were not. Greater FI was associated with less improvement in hip strength of the unaffected leg (coefficient, –1.6, 95% CI: −2.8 to −0.4), although no other significant associations were observed between FI and pre- or postoperative clinical scores. Conclusion: Preoperative FI was not associated with pertinent parameters of patient outcome after hip abductor tendon repair, including pain, symptoms, functional capacity, perceived improvement, and satisfaction. Based on these outcomes, surgical repair may be considered in the presence of more severe FI.

Preoperative IDEAL (Iterative Decomposition of Echoes of Asymmetrical Length) magnetic resonance imaging rotator cuff muscle fat fractions are associated with rotator cuff repair outcomes

IDEAL (Iterative Decomposition of Echoes of Asymmetrical Length) imaging is amagnetic resonance imaging sequence that precisely measures rotator cuff muscle fatty infiltration. The influence of lower levels of fatty infiltration on outcomes after rotator cuff repair remains unclear. We hypothesized that increased preoperative fat fractions would be associated with inferior clinical outcomes after rotator cuff repair. We retrospectively identified patients who underwent arthroscopic rotator cuff repair with preoperative IDEAL imaging. Patients completed the Patient-Reported Outcomes Measurement Information System (PROMIS) Upper Extremity computer adaptive survey at a minimum of 2 years after repair. Muscle segmentation was performed on 4 consecutive slices. Correlations between intramuscular fat fractions and PROMIS scores were determined. Patients were grouped by PROMIS scores of 50 or greater and scores lower than 50 for comparison of fat fractions. Multivariate linear regression was performed to model PROMIS scores as a function of demographic characteristics, tear size, and fat fractions. Significance was defined as P < .05. Eighty patients were included (mean follow-up, 42.5 ± 10.7 months). Postoperative PROMIS scores were significantly inversely correlated with the infraspinatus (ρ = -0.25, P = .02) and subscapularis (ρ = -0.29, P = .009) fat fractions. The infraspinatus (7.2% ± 4.9% vs. 5.2% ± 3.0%, P = .046) and subscapularis (10.4% ± 5.1% vs. 8.2% ± 5.0%, P = .001) fat fractions were significantly higher for patients with low PROMIS scores vs. those with PROMIS scores of 50 or greater. In multivariate modeling, the infraspinatus fat fraction (β = -0.68, P = .029) was the only significant independent predictor of postoperative PROMIS score. Intramuscular fat as determined by quantitative magnetic resonance imaging is an important factor in postoperative outcomes even in patients with lower levels of preoperative fatty infiltration.

The grade of preoperative subscapularis muscle atrophy as a prognostic factor for postoperative retears: A double-center retrospective series.

The aim of the study was to investigate whether subscapularis muscle atrophy is a negative prognostic factor leading to increased risk of retears in patients treated with an arthroscopic subscapularis tendon repair. We hypothesized that fatty infiltration of the subscapularis muscle deteriorates the clinical and sonographic outcome of the arthroscopic repair and inhibits reparability of the ruptured tendons. A double- center, multinational, retrospective, blind (in the follow-up) clinical study regarding 32 patients who underwent an arthroscopic subscapularis repair was conducted. Patients were divided into two groups according to the preoparative fatty infiltration grade of subscapularis muscle (group A: grade<II, group B: grade II or higher). Reparability was not influenced by the grade of preoperative fatty infiltration of subscapularis muscle. The preoperative MRI scans showed significantly higher grades of fatty infiltration (group B) in the subscapularis muscle of patients with clinical evidence of retear after the arthroscopic repair. Low grades of preoperative subscapularis muscle atrophy are significantly correlated with low clinical and sonographic retear’s rate after subscapularis arthroscopic repair, while high grades were a clear negative prognostic factor for the clinical outcome of the aforementioned patients.

Arthroscopic repair of large to massive rotator cuff tears in patients younger than 60 years

BackgroundThe incidence of rotator cuff tears in young patients has increased recently with the increase in sports and recreation activities, however, few studies have reported clinical outcomes after arthroscopic repair of large to massive rotator cuff tears in young patients. This study aimed to evaluate preoperative characteristics and postoperative outcomes after arthroscopic repair of large to massive rotator cuff tears in patients younger than 60 years, and to compare these results with those of tear size-matched patients older than 60 years. MethodsForty-eight patients who underwent arthroscopic repair for large to massive rotator cuff tears were included. Group I (n = 24) consisted of patients younger than 60 years, while tear size-matched patients older than 60 years were assigned to group II (n = 24). Clinical outcomes were evaluated preoperatively and at 3, 6, and 12 months postoperatively, and at the final visit. All patients underwent magnetic resonance imaging (MRI) preoperatively and at 3 and 12 months postoperatively to evaluate repair integrity. ResultsThe mean patient age was 53.4 ± 4.2 years in group I and 67.4 ± 4.5 in group II (P = 0.001). At the last visit, there were no significant differences in postoperative clinical scores or passive range of motion between two groups. However, young patients complained of shoulder pain less frequently than elderly patients (visual analog scale for pain at last visit: 0.8 ± 0.3 in group I, 2.4 ± 1.9 in group II, P = 0.04). Elderly patients showed more advanced fatty infiltration preoperatively than young patients and advanced fatty infiltration was correlated with postoperative repair integrity (r = 0.83, P = 0.001). Postoperative re-tear rate was 12.5% in group I, and 33.3% in group II (P = 0.08). ConclusionMore satisfactory clinical and structural outcomes followed by less advanced preoperative fatty infiltration can be expected in younger patients compared with patients older than 60 years, based on large to massive rotator cuff tear treatment outcomes.

Clinical and Radiographic Outcomes of a Posteriorly Augmented Glenoid Component in Anatomic Total Shoulder Arthroplasty for Primary Osteoarthritis with Posterior Glenoid Bone Loss.

The primary objectives of this study were to evaluate the ability of a posteriorly stepped augmented glenoid component, used in patients with primary glenohumeral osteoarthritis with B2 or B3 glenoid morphology, to correct preoperative retroversion and humeral head subluxation and to identify factors associated with radiographic radiolucency and patient-reported clinical outcomes. We identified 71 shoulders with B2 or B3 glenoid morphology that underwent anatomic total shoulder arthroplasty with use of a posteriorly stepped augmented glenoid component and with a preoperative 3-dimensional computed tomography (3D-CT) scan and a minimum of 2 years of clinical and radiographic follow-up. The Penn Shoulder Score (PSS), shoulder range of motion, glenoid center-peg osteolysis, and postoperative version and humeral head subluxation were the main outcome variables of interest. Follow-up was a median of 2.4 years (range, 1.9 to 5.7 years); the mean patient age at treatment was 65 ± 7 years (range, 51 to 80 years). PSS, range of motion, humeral head centering, and glenoid version were significantly improved among all patients (p < 0.0001). Patients with persistent posterior subluxation of the humeral head postoperatively had worse preoperative fatty infiltration of the teres minor and greater postoperative component retroversion (p < 0.05). Patients with center-peg osteolysis had more preoperative joint-line medialization and posterior glenoid bone loss (p < 0.05). Patients with more preoperative humeral head posterior subluxation had a lower PSS, adjusting for confounders (p < 0.05). Posteriorly stepped augmented glenoid components can improve pathologic retroversion and posterior subluxation of the humeral head in B2 and B3 glenoids, with significant improvements found in clinical outcome scores at a minimum of 2 years of follow-up in the vast majority of patients. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

A Comparative Study to Evaluate the Risk Factors for Medium-Sized Rotator Cuff Tear in Patients Younger Than 50 Years of Age

The purpose of this study was to evaluate preoperative and intraoperative factors associated with rotator cuff tears (RCTs) among patients younger than 50years and to compare arthroscopic rotator cuff repair (RCR) results in patients younger than 50years (group A) and patients older than 70years (group B). We also analyzed the results after arthroscopic RCR in these 2 age groups. Data were collected from 56 patients allocated to group A and 55 patients allocated to group B who had medium-sized RCTs and had undergone arthroscopic RCR between January 2006 and August 2015. Preoperative variables included demographic data, radiologic data, and surgical procedure. We evaluated fatty degeneration on preoperative magnetic resonance imaging (MRI) and intraoperative variables, including concomitant subscapularis repair, as well as repair technique. Pain visual analog scale, functional visual analog scale, American Shoulder and Elbow Surgeons, and Constant scores were documented to compare functional results in each age group. Postoperative MRI scans were conducted to evaluate the retear rate after RCR after a mean postoperative duration of 5.4months (range, 2-48months). Multivariate regression analysis showed acute-on-chronic injury and a history of hypertension were independent factors for differentiation of the groups. Stepwise regression analysis found sex, hypertension, and fatty infiltration of the supraspinatus and infraspinatus to be comparable factors for each group. All patients showed improved results after arthroscopic RCR, but there was no difference between the 2 groups in functional outcomes. However, cuff retears on postoperative MRI scans were found in only 3.9% of the patients in group A versus 16% of the patients in group B. The results of this study showed that sex, acute-on-chronic injury, and preoperative fatty infiltration of the rotator cuff were significant factors affecting medium-sized RCTs in patients younger than 50years. In addition, there were no significant differences in functional outcomes after arthroscopic RCR in bothgroups at 2years, but postoperative MRI showed a lower retear rate in group A. Level III, retrospective comparative study.

Paralabral cysts of the shoulder treated with isolated labral repair: effect on pain and radiologic findings

Paralabral cysts emanating from posterosuperior labral tears may compress the suprascapular nerve and induce neuropathy. This study prospectively assessed patients with labral tears and symptomatic paralabral cysts treated with isolated labral repair. Pain relief, time to cyst resolution, reversibility of muscular edema, atrophy, fatty infiltration, and bone erosion were evaluated. Forty-seven patients with symptomatic posterosuperior paralabral cysts were treated with isolated labral repair. Magnetic resonance imaging (MRI) was repeated 6 and 12 weeks postoperatively or until cyst resolution. In a subgroup of 15 patients, MRI was performed the day before the operation, the first postoperative day, and at 2 weeks. Median cyst size was 6.8 cm3 (range, 2.1-88.9; standard deviation [SD], 18.3 cm3). Preoperatively, 20 patients (43%) presented clinical muscle atrophy and radiologic edema on MRI, 8 had fatty infiltration, and 3 presented bony scapular erosion caused by cyst compression. Median time to cyst resolution and regression of muscular edema was 11 weeks (range, 3-20; SD, 8.8 weeks) and 14 weeks (range, 3-52; SD 10.6 weeks), respectively. Preoperative fatty infiltration grade I and II of the supraspinatus and infraspinatus muscles was reduced in two patients. Bony erosions remodeled after cyst resolution. Mean pain ratings (1-10 scale) improved from 7.7 (SD, 1.8) to 1.3 (SD, 1.3; 95% confidence interval of difference, 5.5-6.8; P < .001). Labral repair leads to significant pain relief with cyst resolution within 2 to 3 months in most patients. Secondary muscle pathology (ie, edema, atrophy and fatty infiltration) may be partially or completely reversed. Bony erosion caused by cyst compression may be remodeled after cyst resolution.

Fatty infiltration and muscle atrophy of the rotator cuff in stemless total shoulder arthroplasty: a prospective cohort study

The influence of preoperative rotator cuff fatty infiltration (FI) and muscle atrophy (MA) on the postoperative outcome of total shoulder arthroplasty (TSA) has only rarely been investigated and reported in the literature. We hypothesized that more FI and MA would be associated with a worse postoperative functional outcome. This prospective cohort study included 63 patients (31 female and 32 male patients; mean age, 71 years [range, 53-89 years; standard deviation, 7 years]) with primary osteoarthritis of the shoulder operated on with anatomic stemless TSA. Preoperatively and at 3 months and 1 year after the operation, the functional outcome (QuickDASH [short version of Disabilities of the Arm, Shoulder and Hand questionnaire] score) and range of motion (ROM) (goniometer) and strength (dynamometer) for abduction at the scapular plane and for external rotation were measured. The degree of preoperative FI and MA was evaluated using computed tomography scans according to the Goutallier classification and Warner classification, respectively, for the supraspinatus and infraspinatus. We found clinically and statistically significant improvements in functional outcome, strength, and ROM at both 3 months and 1 year of follow-up compared with those preoperatively. The Pearson correlation coefficient (r) showed significant correlations between preoperative supraspinatus and infraspinatus FI and MA and preoperative and 1-year postoperative shoulder abduction and external rotation strength but not ROM. However, we found no influence of the rotator cuff FI and MA on the functional outcome after TSA. We demonstrated a significant correlation between rotator cuff FI and MA and strength but not ROM of the shoulder joint.

Fatty degeneration of the deltoid muscle associated with displaced proximal humerus fractures

The use of reverse shoulder arthroplasty (RSA) has increased dramatically over the last two decades, with many surgeons now indicating RSA for the acute management of displaced proximal humerus fractures (PHF) in the elderly. RSA relies on adequate deltoid muscle function to obtain a good outcome, yet no literature to date exists which discusses preoperative assessment of deltoid structure prior to RSA. The purpose of this study was to assess for preoperative fatty deltoid-degeneration in patients with displaced PHF. We reviewed the axial CT scans of 100 consecutive patients with a displaced PHF. Fatty degeneration within each of the three deltoid-heads was graded at three levels, according to Goutallier and colleagues. Fractures were classified according to Neer. Seventy-nine percent of the patients were female, 75% showed 3 or 4 parts fractures. The average cross-sectional area of the posterior deltoid was greatest-representing 37%, 40% and 42% of total area at each level, respectively. Severe fatty degeneration (Stages 3 and 4) was observed in the posterior deltoid only (26%). Absence of fatty degeneration (Stage 0) was observed in < 25% of cases. The Inter-Observer-Reliability for the continuous variables proved to be high. Preoperative deltoid fatty degeneration is common in displaced PHF in the elderly. Because CT is commonly obtained to assess fracture morphology and for preoperative planning purposes, it is an ideal tool to assess the deltoid additionally. Future studies are warranted to determine whether preoperative fatty infiltration of the deltoid correlates with mid and long term functional outcomes when RSA is used acutely to manage a PHF. Level IV-consecutive case series.

Fatty infiltration of the supraspinatus on a single sagittal-oblique “Y” view) CT image does not accurately predict the entire muscle condition

Introduction The condition of rotator cuff muscles is an important parameter to consider in shoulder arthroplasty, both preoperatively and postoperatively. We developed and compared 2D and 3D quantitative CT methods, and assessed whether supraspinatus muscle degeneration measured on a single sagittal-oblique (“Y” view) CT slice was equivalent to measurements obtained on several or all CT slices encompassing the muscle. Materials and methods We selected 19 patients (12 females, 68.7 ± 11.5 years) who underwent standardized CT prior to shoulder arthroplasty and were divided in two groups: 9 patients had a full-thickness complete supraspinatus tendon tear, while 10 patients had no tear. Preoperative shoulder CT images were reconstructed semi-automatedly to obtain the reference sagittal-oblique (“Y view”) CT slice. Two radiologists independently delineated the contours of the supraspinatus muscle on consecutive 1 mm thick CT slices, from the myotendinous junction laterally to the medial border of the scapula. Muscle degeneration ratios consisting of atrophy, fatty infiltration, and secondary bone formation were then automated quantified for the single reference CT slices, 3 slices (reference + 1 cm medially and 1 cm laterally), 10 slices (reference + 7 slices medially and 2 slices laterally, each at 1 cm interval), as well as for all (range 100–134) slices encompassing the supraspinatus muscle. The interobserver reproducibility of measurements was evaluated. Resultats Supraspinatus atrophy (0.54 ± 0.24) was the main determinant of muscle degeneration (0.55 ± 0.24) on the reference CT slice. Supraspinatus muscle degeneration ratios were significantly higher in patients with full-thickness complete tendon tears (0.71) than in patients with no tear (0.40) (P = 0.004). Fatty infiltration was significantly higher when measured on 10 CT slices than on the single reference slice (P = 0.048). There were no significant differences between 1, 3, 10, and all slices for atrophy, secondary bone formation, and degeneration (P > 0.383). Subgroup analysis revealed that fatty infiltration was significantly underestimated on the single reference slice in patients with full-thickness complete tears, as compared with 10 (P 0.135). There were no significant differences in patients with no tear (P > 0.737). Interobserver reproducibility of measurements was excellent (P > 0.990). Discussion Care must be taken when assessing preoperative fatty infiltration of the supraspinatus muscle on a single sagittal-oblique CT-slice. Conclusion Fatty infiltration of the supraspinatus muscle quantified on a single sagittal-oblique CT slice differs significantly from measurements obtained on 10 CT slices, particularly in patients with full-thickness complete tendon tears.