Severe Fatty Infiltration Research Articles

Correlation of BMI and elevated liver enzyme levels with severity of fatty liver infiltration on ultrasound in Sangrur, Punjab

Obesity is a common disorder in our country. It leads to many health risks. Ultrasonography can accurately assess the severity of fatty infiltration in liver. The liver enzymes (AST, ALT) are also altered in triglyceride overload. This study aims to assess the severity of fatty liver on US (Ultrasonography) with increased BMI and to investigate the association of severity of fatty liver with liver enzymes. A comparative prospective study was conducted on 179 patients. Severity of fatty liver was graded on Ultrasonography as follows- Group A- Normal liver, Group B- Grade 1 fatty changes, Group C-Grade 2 fatty changes and Group D-Grade 3 fatty changes. BMI of each patient was calculated. Patients with known liver disease were excluded. Serum liver enzyme levels were recorded. There was significant correlation between value of liver enzymes and increasing BMI. Also, Patients with more BMI have higher grade of fatty infiltration. Keywords: Obesity, AST, ALT, Ultrasonography

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.

Arthroscopic Superior Capsular Reconstruction Using “Sandwich” Patch Technique for Irreparable Rotator Cuff Tears

The technique of superior capsular reconstruction (SCR) using fascia lata autograft, described by Mihata et al. in 2012, has been an acceptable and effective method for treating irreparable massive rotator cuff tears, especially in cases with severe fatty infiltration and tendon retraction. After the SCR procedure of Mihata et al., it was found that some graft failure occurred with thinning and elongation during the follow-up time, which was called graft “creep.” To avoid graft creep and reduce graft failure rates after SCR, we created an arthroscopic SCR technique with a “sandwich” patch augmented with polyethylene terephthalate scaffold interspaced between 2 folded layers of fascia lata autograft.

Inferior outcome of rotator cuff repair in chronic hemodialytic patients

BackgroundRepair of rotator cuff tears has yielded excellent functional outcomes in recent decades; however, poor outcomes and dissatisfaction have been noted in specific groups. Spontaneous tendon rupture has been reported in patients receiving long-term hemodialysis owing to alteration of tendon structure, which might impede functional recovery after rotator cuff repair. The purpose of the present study was to compare the clinical outcomes between hemodialysis and non-hemodialysis patients after rotator cuff repair.MethodsWe retrospectively reviewed patients who underwent mini-open rotator cuff repair from Jan 2013 to Jan 2017. A total of 14 patients under chronic hemodialysis (HD) were matched to non-hemodialysis (NHD) patients at a 1:2 ratio according to age, gender, tear size, severity of fatty infiltration and history of diabetes. Pre- and post-operative functional outcome was assessed using the simple shoulder test (SST), American Shoulder and Elbow Surgeons (ASES), Shoulder Rating Scale of the University of California at Los Angeles (UCLA) and visual analog scale (VAS) scores. Clinical functional outcome at the last follow-up was adopted for comparison of the HD and NHD groups.ResultsA total of 42 patients were enrolled in this comparative study, with a mean age of 66.64 ± 1.68 years in the HD group and 65.71 ± 5.40 years in the NHD group. At the final clinical assessment, the post-operative functional outcome was significantly improved in both groups (p < 0.001). However, the functional outcome of the HD group was significantly inferior to that of the NHD group in terms of the SST score (6.50 ± 2.24 vs 9.39 ± 1.87, p < 0.001), ASES score (63.17 ± 15.93 vs 86.96 ± 11.43, p < 0.001), UCLA score (20.14 ± 7.71 vs 29.82 ± 5.08, p < 0.001) and VAS score (3.00 ± 0.96 vs 1.21 ± 1.03, p < 0.001).ConclusionThe improvement of pain and functional improvement of long-term hemodialysis patients were inferior to those of patients without hemodialysis after mini-open rotator cuff repair.

Influence of a nerve injury proximal to the suprascapular nerve on healing of repaired rotator cuff tear

BackgroundMassive rotator cuff tears have a high rate of re-injury because of severe fatty infiltration. Our data showed that injuries proximal to the suprascapular nerve may be one cause of massive rotator cuff tears. The purpose of this study was to evaluate, using a rat model, how brachial plexus injury associated with a massive rotator cuff tear influences healing of the rotator cuff repair. MethodsSeventy Sprague–Dawley rats were divided into three groups: rotator cuff tear with BP injury (DT group) (n = 28), rotator cuff tear without brachial plexus injury (T group) (n = 28), and a sham-operated group (n = 14). In the DT group, the rotator cuff tear was made and repaired 4 weeks after brachial plexus ligation. The gross assessment (evaluated the wet weight), biomechanical testing (evaluated the yield stress and the Young's modulus) and histological analyses (using the Bonar scale) were performed at baseline in the sham group, and at 4 and 12 weeks postoperatively in the DT and T groups (n = 7/group/time). ResultsMean wet weight and yield stress were significantly lower in the DT group than in the T group. Additionally, the mean Young's modulus was significantly higher in the DT group than in the T group. Histologically, greater tendon degeneration was observed around the musculotendinous junction in the DT group than in the T group. ConclusionThe gross, biomechanical and histological data show that the repaired rotator cuff tendon with brachial plexus injury in rats does not heal as well as a repaired tendon without an accompanying brachial plexus injury. This suggests that more proximal neuropathy is one risk factor for re-tear of a repaired rotator cuff tendon.

Three-dimensional characterization of the anteverted glenoid (type D) in primary glenohumeral osteoarthritis

The Walch classification describes glenoid morphology in primary arthritis. As knowledge grows, several modifications to the classification have been proposed. The type D, a recent modification, was defined as an anteverted glenoid with or without anterior subluxation. Literature on the anteverted glenoid in primary osteoarthritis is limited. The purpose of this study, therefore, was to analyze the anatomic characteristics of the type D glenoid on radiographs and computed tomography (CT). The shoulder arthroplasty databases from 3 institutions were examined to identify patients with primary glenohumeral osteoarthritis and glenoid anteversion (≥5°), with or without anterior subluxation. The type D study cohort consisted of 18 patients (3% of the osteoarthritis cohort) and was a mean of 70 years old, with 11 women and 7 men. All radiographs were reviewed, and computed tomography Digital Imaging and Communications in Medicine (National Electrical Manufacturers Association, Rosslyn, VA, USA) data were analyzed on validated 3-dimensional imaging software. Rotator cuff fatty infiltration, glenoid measurements (anteversion and inclination), and humeral head subluxation according to the scapular plane were determined. In the study cohort, the mean glenoid anteversion was 12° (range, 5°-24°), the mean inclination was 0°, and the mean anterior subluxation was 38% (range, 6%-56%). Eight patients (44%) had a biconcave glenoid with a posterosuperiorly positioned paleoglenoid and an anteroinferiorly positioned neoglenoid, and 10 patients had a monoconcave glenoid. Fatty infiltration of the rotator cuff muscles never exceeded Goutallier stage 2. The type D glenoid is an addition to the original Walch classification and is characterized by glenoid anteversion (≥5°), anteroinferior humeral head subluxation, and absence of severe subscapularis fatty infiltration.

Fatty pancreas: A possible risk factor for pancreatic cancer in animals and humans.

Obesity, type 2 diabetes mellitus (T2DM) and aging are associated with pancreatic cancer risk, but the mechanisms of pancreatic cancer development caused by these factors are not clearly understood. Syrian golden hamsters are susceptible to N‐nitrosobis(2‐oxopropyl)amine (BOP)‐induced pancreatic carcinogenesis. Aging, BOP treatment and/or a high‐fat diet cause severe and scattered fatty infiltration (FI) of the pancreas with abnormal adipokine production and promote pancreatic ductal adenocarcinoma (PDAC) development. The KK‐A y mouse, a T2DM model, also develops severe and scattered FI of the pancreas. Treatment with BOP induced significantly higher cell proliferation in the pancreatic ducts of KK‐A y mice, but not in those of ICR and C57BL/6J mice, both of which are characterized by an absence of scattered FI. Thus, we hypothesized that severely scattered FI may be involved in the susceptibility to PDAC development. Indeed, severe pancreatic FI, or fatty pancreas, is observed in humans and is associated with age, body mass index (BMI) and DM, which are risk factors for pancreatic cancer. We analyzed the degree of FI in the non‐cancerous parts of PDAC and non‐PDAC patients who had undergone pancreatoduodenectomy by histopathology and demonstrated that the degree of pancreatic FI in PDAC cases is significantly higher than that in non‐PDAC controls. Moreover, the association with PDAC is positive, even after adjusting for BMI and the prevalence of DM. Accumulating evidence suggests that pancreatic FI is involved in PDAC development in animals and humans, and further investigations to clarify the genetic and environmental factors that cause pancreatic FI are warranted.

Fatty infiltration evaluation and selective pattern characterization of lower limbs in limb‐girdle muscular dystrophy type 2A by muscle magnetic resonance imaging

Limb-girdle muscular dystrophy type 2A (LGMD2A) is characterized by progressive wasting of muscles for which the disease-monitoring tools are still deficient. We performed muscle MRI of the lower limbs in 32 LGMD2A patients and 21 controls. The modified Mercuri scale was employed to evaluate the degree of fatty infiltration. Severe fatty infiltration in the long head of biceps femoris (modified Mercuri scale 3.99) and sparing of extensor digitorum longus (modified Mercuri scale 0.17) were observed. The sensitivity and specificity of this pattern in diagnostic testing was 76.00% and 90.48%, respectively. A comprehensive clinical and MRI evaluation revealed that progressive fatty infiltration in the upper leg correlated well with disease progression, but neither calf involvement nor muscle strength deterioration showed a good correlation. The selective involvement pattern is potentially useful for LGMD2A diagnosis. Upper leg muscle MRI is a sensitive evaluation method for monitoring disease progression. Muscle Nerve 58: 536-541, 2018.

Magnetic Resonance Imaging Findings in the Muscle Tissue of Patients with Limb Girdle Muscular Dystrophy Type 2I Harboring the Founder Mutation c.545A>G in the FKRP Gene.

Limb girdle muscular dystrophy type 2I (LGMD2I) is an autosomal recessive muscular dystrophy that is rare in Asia and is caused by mutations in the fukutin-related protein gene (FKRP). The aim of this study was to determine if there are any characteristic features of muscle on magnetic resonance imaging (MRI) in patients with LGMD2I harboring the founder mutation c.545A>G in FKRP. Using MRI, we delineated changes in the thigh muscles of ten patients with genetically confirmed LGMD2I. The majority of muscle biopsy specimens showed reduced glycosylation of α-dystroglycan, decreased expression of laminin α2, and a dystrophic pattern. In our cohort, the muscles with the most severe fatty infiltration were adductor magnus and vastus intermedius, whereas the rectus femoris, sartorius, and gracilis muscles were relatively spared. In seven patients, we identified a concentric fatty infiltration pattern that was most pronounced in the vastus intermedius and vastus medialis muscles around the distal femoral diaphysis. In this disease, the initial fatty infiltration of the posterior thigh muscles gradually progresses anteriorly regardless of the founder mutation in FKRP. Muscle tissue in patients with LGMD2I who have the founder mutation c.545A>G in FKRP shows a distinctive concentric pattern of fatty infiltration and edema on MRI.

A Rotator Cuff Tear Concomitant With Shoulder Stiffness Is Associated With a Lower Retear Rate After 1-Stage Arthroscopic Surgery

Background: Few studies have reported on the radiological characteristics and repair integrity of coexistent rotator cuff tears (RCTs) and shoulder stiffness after simultaneous arthroscopic rotator cuff repair and capsular release. Purpose: To evaluate the radiological characteristics and repair integrity of 1-stage arthroscopic surgery of RCTs concomitant with shoulder stiffness. Study Design: Cohort study; Level of evidence, 3. Methods: Among patients who underwent arthroscopic repair of full-thickness RCTs, the stiff group underwent simultaneous capsular release for shoulder stiffness, and the nonstiff group had no stiffness. Symptom duration, prevalence of diabetes, tear size, tendon involvement (type 1, supraspinatus; type 2, supraspinatus and subscapularis; and type 3, supraspinatus and infraspinatus; type 4, supraspinatus, subscapularis, and infraspinatus), and fatty infiltration (Goutallier stages 0-4) were evaluated. A retear was appraised using magnetic resonance imaging, and clinical outcomes were assessed using range of motion, the Korean Shoulder Scoring System (KSS), and the University of California, Los Angeles (UCLA) shoulder score. Results: The stiff group showed a significantly lower retear rate (1/39, 2.6%) than the nonstiff group (47/320, 14.7%) (P = .043). There were significant differences in symptom duration (7.4 ± 6.6 vs 15.0 ± 23.7 months, respectively; P < .001), mediolateral tear size (18.9 ± 8.9 vs 24.1 ± 12.0 mm, respectively; P = .002), tendon involvement (94.9%, 5.1%, 0.0%, and 0.0% vs 85.3%, 6.9%, 7.8%, and 0.0%, respectively; P = .048), and fatty infiltration of the subscapularis (66.7%, 33.3%, 0.0%, 0.0%, and 0.0% vs 31.9%, 61.3%, 5.6%, 1.3%, and 0.0%, respectively; P < .001) and teres minor (74.4%, 20.5%, 5.1%, 0.0%, and 0.0% vs 47.2%, 48.8%, 3.8%, 0.0%, and 0.3%, respectively; P = .007) between the stiff and nonstiff groups. Preoperatively, the stiff group showed significantly worse forward flexion (95.9° ± 23.6° vs 147.7° ± 4.2°, respectively; P < .001), external rotation (17.4° ± 10.1° vs 51.6° ± 12.1°, respectively; P < .001), and internal rotation (L5 vs L2, respectively; P < .001) and lower KSS (52.1 ± 13.8 vs 66.3 ± 13.5, respectively; P < .001) and UCLA scores (18.7 ± 4.8 vs 22.5 ± 4.5, respectively; P < .001) than the nonstiff group. However, these differences became insignificant from 3 months postoperatively for forward flexion (P > .05) and KSS (P > .05) and UCLA scores (P > .05), from 1 year postoperatively for external rotation (P > .05), and at the last follow-up for internal rotation (P > .05). A multiple logistic regression analysis revealed that only mediolateral tear size (odds ratio, 1.043; P = .014) and type 2 tendon involvement (odds ratio, 4.493; P = .003) were independent predictors of a retear. Conclusion: RCTs concomitant with shoulder stiffness showed a smaller mediolateral tear size, anterosuperior tendon involvement, and less severe fatty infiltration preoperatively and better repair integrity postoperatively than RCTs without stiffness. Furthermore, the clinical outcomes and range of motion at final follow-up were similar between the 2 groups.

Computed tomography underestimates rotator cuff pathology in patients with glenohumeral osteoarthritis

Computed tomography (CT) is the standard assessment of glenoid morphology before shoulder arthroplasty and is commonly used to evaluate rotator cuff pathology in patients with glenohumeral osteoarthritis (GHOA). Magnetic resonance imaging (MRI) is not routinely used in this setting but has higher sensitivity in diagnosing full-thickness rotator cuff tears (RCT) and is considered the gold standard. The purpose of this study was to determine the sensitivity and specificity of CT in diagnosing full-thickness RCTs and compare the evaluation of fatty infiltration and muscle atrophy on CT vs. MRI in the setting of GHOA. In this retrospective case-controlled study, we identified 49 patients from a prospectively maintained 2-surgeon registry who received preoperative CT and MRI scans for the evaluation of GHOA between 2011 and 2016. Three fellowship-trained shoulder surgeons assessed rotator cuff integrity, fatty infiltration, and muscle atrophy in the CT and MRI scans. CT sensitivity and specificity were 20% and 95.5%, respectively. Fatty infiltration was significantly lower on CT for the supraspinatus (P = .003), infraspinatus (P < .001), and subscapularis (P = .0182), whereas muscle atrophy was significantly lower on CT for only the supraspinatus (P = .0023). Our results suggest that CT underestimates the frequency of full-thickness RCTs and the severity of fatty infiltration and muscle atrophy in the setting of GHOA before total shoulder arthroplasty.

Effect of recombinant human growth hormone on rotator cuff healing after arthroscopic repair: preliminary result of a multicenter, prospective, randomized, open-label blinded end point clinical exploratory trial

This study evaluated the effect of systemic injection of recombinant human growth hormone (rhGH) on outcomes after arthroscopic rotator cuff repair. This multicenter, prospective, randomized, comparative trial, randomized patients who underwent arthroscopic repair of large-sized rotator cuff tears into 3 groups: rhGH 4 mg group (n = 26), rhGH 8 mg group (n = 24) , and control group (n = 26). Sustained release rhGH was injected subcutaneously once weekly for 3 months postoperatively. The healing failure rate (primary end point), fatty infiltration, and atrophy of the supraspinatus muscle, and functional scores (Constant and American Shoulder and Elbow Surgeons scores) were evaluated at 6 months. Range of motion, pain visual analog scale, and serum insulin-like growth factor-1 level were measured at each follow-up. The healing failure rate was similar between groups (rhGH 4 mg group, 30.8%; rhGH 8 mg group, 16.7%; and control group, 34.6%; all P > .05) The proportion of severe fatty infiltration (Goutallier grade ≥3) was 20.8% in the rhGH 8 mg group, 23.1% in the rhGH 4 mg group, and 34.6% in the control group (P > .05). Functional outcomes, range of motion, and pain visual analog scale were similar between groups (all P > .05). The rhGH 8 mg group showed more increased peak insulin-like growth factor-1 level (279.43 ng/mL) than the rhGH 4 mg group ((196.82 ng/mL) and control group (186.31 ng/mL), which was not statistically different (all P > .05). No rhGH injection-related major safety issues occurred. This preliminary study showed no statistically significant improvement in healing or outcomes related to the treatment of rhGH after rotator cuff repair. However, further study with more enrolled patients after resetting the rhGH dose or daily administration protocol would be mandatory.

Isolated loss of active external rotation: a distinct entity and results of L'Episcopo tendon transfer

The purpose of this study was to characterize a subgroup of cuff-deficient patients with isolated loss of active external rotation (ILER) but preserved active elevation and to evaluate the outcomes of the L'Episcopo procedure to restore horizontal muscle balance. During a 10-year period, 26 patients (14 men, 12 women) were identified with ILER in the setting of massive irreparable posterosuperior cuff tears. A modified L'Episcopo tendon transfer was performed to restore active external rotation and to improve shoulder function. The mean age at surgery was 64.5 years (29-83 years). Patients were evaluated with a mean follow-up of 52 months (range, 24-104 months). Preoperatively, despite maintained active elevation (average of 161°), ILER patients complained about loss of spatial control of the arm and difficulties with activities of daily living. On computed tomography scan or magnetic resonance imaging, there was severe fatty infiltration of infraspinatus and absent or atrophic teres minor. After L'Episcopo transfer, 84% of patients were satisfied. The gain in active external rotation was +26° in arm at the side and +18.5° in 90° abduction. Adjusted Constant score and Simple Shoulder Value increased from 63.6% to 86.9% and from 36.9% to 70.8%, respectively (P < .001). The ADLER score increased from 10 to 24.5 points (P < .002). Two patients with advanced cuff tear arthropathy (Hamada stage 3 and 4) required conversion to a reverse shoulder arthroplasty (RSA) 7 and 9 years after the index surgery. ILER is a distinct entity that is a cause of severe handicap because of loss of spatial control of the upper limb. This symptom is related to absent or atrophied infraspinatus and teres minor. In properly selected cases (Hamada stage 1 or 2), the modified L'Episcopo transfer is effective at restoring anterior-posterior rotator cuff force balance. In more advanced cuff tear arthropathy (Hamada stage ≥3), the tendon transfer should be performed with an RSA because of possible secondary degeneration of the glenohumeral joint.

Ten-year clinical and anatomic follow-up after repair of anterosuperior rotator cuff tears: influence of the subscapularis

Anterosuperior rotator cuff tears are more frequent than expected. We report the results of a 10-year follow-up study after repair. Our hypothesis was that the extent of the subscapularis tear influenced the prognosis. The study population consisted of all 138 patients who underwent surgery in 14 participating centers in 2003 for full-thickness tears of the rotator cuff with lesions in the subscapularis and supraspinatus tendons. The patients were divided into 2 groups, depending on whether the subscapularis lesion affected only the superior half of the tendon (group A) or extended into the lower half (group B). Ninety-two patients (56 ± 7 years; 71 in group A and 21 in group B) were available for follow-up after 10 years (127 ± 16 months) with magnetic resonance imaging to evaluate tendon healing and muscle condition. The mean Constant scores were 59 ± 16 before surgery and 77 ± 14 at follow-up (P = 1.7 × 10-12). The retear rates were 25% for the supraspinatus and 13.5% for the subscapularis tendon. The clinical results for group A patients were better than those for group B. Severe fatty infiltration was observed more frequently in the subscapularis than in the supraspinatus muscle (27% vs. 12% of cases). Supraspinatus healing influenced subscapularis healing and fatty infiltration. Repair of anterosuperior rotator cuff tears is satisfactory at 10 years, particularly if the subscapularis tear is not extensive. An extensive subscapularis tear is a negative prognosis factor. Postoperatively, fatty infiltration of the subscapularis muscle was frequently observed despite tendon healing.

Quantitative assessment of fatty infiltration and muscle volume of the rotator cuff muscles using 3-dimensional 2-point Dixon magnetic resonance imaging

In patients with rotator cuff tears, muscle degeneration is known to be a predictor of irreparable tears and poor outcomes after surgical repair. Fatty infiltration and volume of the whole muscles constituting the rotator cuff were quantitatively assessed using 3-dimensional 2-point Dixon magnetic resonance imaging. Ten shoulders with a partial-thickness tear, 10 shoulders with an isolated supraspinatus tear, and 10 shoulders with a massive tear involving supraspinatus and infraspinatus were compared with 10 control shoulders after matching age and sex. With segmentation of muscle boundaries, the fat fraction value and the volume of the whole rotator cuff muscles were computed. After reliabilities were determined, differences in fat fraction, muscle volume, and fat-free muscle volume were evaluated. Intra-rater and inter-rater reliabilities were regarded as excellent for fat fraction and muscle volume. Tendon rupture adversely increased the fat fraction value of the respective rotator cuff muscle (P < .002). In the massive tear group, muscle volume was significantly decreased in the infraspinatus (P = .035) and increased in the teres minor (P = .039). With subtraction of fat volume, a significant decrease of fat-free volume of the supraspinatus muscle became apparent with a massive tear (P = .003). Three-dimensional measurement could evaluate fatty infiltration and muscular volume with excellent reliabilities. The present study showed that chronic rupture of the tendon adversely increases the fat fraction of the respective muscle and indicates that the residual capacity of the rotator cuff muscles might be overestimated in patients with severe fatty infiltration.

Semitendinosus and gracilis free muscle-tendon graft for repair of massive rotator cuff tears: surgical technique

Massive rotator cuff tears are difficult to treat surgically due to retraction, degeneration and fraying of the ends of torn tendons, severe fatty infiltration and atrophy of the respective muscles. Procedures developed to close the gap between the rotator cuff and the greater tuberosity of the humerus, such as soft tissue release may be inadequate for large tears. Human or porcine dermal allografts still have uncertain benefits, and tendon transfers seem to be associated with poor outcomes, donor site morbidity and altered mechanics. Reverse total shoulder arthroplasty has limited durability and is not indicated in young patients with high functional demands. We developed a new technique for repairing massive rotator cuff tears by semitendinosus and gracilis myotendinous grafting. This novel therapeutic option allows massive rotator cuff tears to be repaired using autologous material that is adequate and adaptable, making it possible to cover any width of defect. The technique is low-invasive and not technically demanding, with minimal donor site morbidity.

Paper #39 - Reduced muscle degeneration and decreased fatty infiltration after rotator cuff tear in a PARP-1 knock-out mouse model

Introduction: Disturbed muscular architecture, fatty infiltration and muscular atrophy remain irreversible in chronic rotator cuff tears (RCT) even after repair. Poly-[ADP-ribose]-polymerase 1 (PARP1), a nuclear factor involved in DNA damage repair, has shown to be a key element in the up-regulation of early muscle inflammation, atrophy and fat deposition. We therefore hypothesized that the absence of PARP1 would lead to a reduction in muscular architectural damage, early inflammation, atrophy and fatty infiltration subsequent to combined tenotomy and neurotomy in a PARP1 knock-out mouse model. Methods: PARP1 knock-out (KO group) and standard wild type C57BL/6 (WT group) mice were randomly allocated into three different time points (1, 6 and 12 weeks, total n = 72). In all mice the supraspinatus (SSP) and infraspinatus (ISP) tendons of the left shoulder were detached and the SSP muscle was denervated according to a recently established model. Macroscopic muscle weight analysis, retraction documentation using macroscopic suture, magnetic resonance imaging, immunohistochemistry gene expression analysis using real time qPCR (RTqPCR) and histology were used to assess the differences in muscle architecture, early inflammation, fatty infiltration and atrophy between knock out and wild type mice in the supraspinatus muscle. Results: The SSP did retract in both groups, however; the KO muscles and tendons retracted less than the WT muscles (2.1 ± .21 mm vs 3.4 ± .41 mm;P = .02). Further assessment of muscle architecture demonstrated that the pennation angle was significantly lower in the KO groups at 6 and 12 weeks (28 ± 5 vs 36 ± 5 and 29 ± 4 vs 34 ± 3; P < .0001). Combined Tenotomy and neurotomy resulted in a significant loss of muscle mass in both groups compared to the contralateral unoperated side (KO group 62 ± 11% and WT group 52 ± 11%, P = .04) at 6 weeks. But at 12 weeks postoperatively, there was a significant increase in muscle mass to near normal levels in KO group compared to the WT group (14 ± 6% and 42 ± 7% lower muscle mass respectively; P < .0001). Immunohistochemistry revealed a significant decrease in the expression of inflammatory, apoptotic, adipogenic and muscular atrophy genes at both the 1 week and 6 weeks time points, but not at 12 weeks in the KO group compared to the WT group. This was confirmed by histology. Discussion: Our study is the first to show that knocking out PARP1 leads to decreased loss of muscle architecture, early inflammation, fatty infiltration and atrophy after combined tenotomy and neurotomy of the rotator cuff muscle. Although KO and WT mice developed severe atrophy and fatty infiltration 6 weeks after surgery, the muscles of the KO mice regenerated to almost normal size after 12 weeks. We conclude that PARP1 has an influence on the muscular deterioration after RCT.

Hematemesis in a Child on Olanzapine

The case of a 13-year old boy with hepatic steatosis secondary to atypical antipsychotic use is described. The patient presented with a single episode of moderate-volume hematemesis and was found to have severe fatty infiltration and ductal dilatation of the liver. These changes were attributed to the patient’s use of olanzapine for behavioral disorders related to autism spectrum disorder. The differential diagnosis of pediatric hematemesis is described, as well as the importance of considering adverse drug affects in patients maintained on olanzapine and other antipsychotics.

¿Existe infiltración grasa del cuádriceps en la lesión crónica del tendón patelar?

IntroductionThere are no models that evaluate the morphological changes of the muscles in chronic ruptures of the extensor apparatus of the knee. Objectives1) To describe a new model of chronic rupture of the patellar tendon; and 2) To macroscopically and histologically evaluate progressive quadriceps muscle degeneration. HypothesisThere is progressive fibrosis and fatty infiltration of the quadriceps muscle. Materials and methodA complete transection was performed on the right patellar tendon of 20 male, adult, BKS mice, divided into 4 groups of 5 animals. The animals were sacrificed at the 1st, 2nd, 4th, and 12th week after the indicated procedure. After sacrificing the animals, both quadriceps muscles were resected and evaluated macroscopically, morphometrically, and histologically by 2 independent, blinded pathologists. Statistical analysis was performed using Student t test, and Wilcoxon's test (P<.05) ResultsMacroscopy yellowish muscle tissue with significant progressive morphological changes beginning at week 2. Histology: progressive fatty infiltration with numerous atrophies of the muscle fibres, becoming significant after the 4th week, reaching severe fatty infiltration at week 12, with little fibrous tissue in less than 6% of the muscle. ConclusionsThis new model of patellar tendon chronic rupture is associated with persistent discontinuity of the knee extensor mechanism and structural changes of the quadriceps muscle. These changes include muscle atrophy and progressive fatty infiltration beginning at the 2nd week after the injury.

Muscle Quantitative MR Imaging and Clustering Analysis in Patients with Facioscapulohumeral Muscular Dystrophy Type 1.

BackgroundFacioscapulohumeral muscular dystrophy type 1 (FSHD1) is the third most common inherited muscular dystrophy. Considering the highly variable clinical expression and the slow disease progression, sensitive outcome measures would be of interest.Methods and FindingsUsing muscle MRI, we assessed muscular fatty infiltration in the lower limbs of 35 FSHD1 patients and 22 healthy volunteers by two methods: a quantitative imaging (qMRI) combined with a dedicated automated segmentation method performed on both thighs and a standard T1-weighted four-point visual scale (visual score) on thighs and legs. Each patient had a clinical evaluation including manual muscular testing, Clinical Severity Score (CSS) scale and MFM scale. The intramuscular fat fraction measured using qMRI in the thighs was significantly higher in patients (21.9 ± 20.4%) than in volunteers (3.6 ± 2.8%) (p<0.001). In patients, the intramuscular fat fraction was significantly correlated with the muscular fatty infiltration in the thighs evaluated by the mean visual score (p<0.001). However, we observed a ceiling effect of the visual score for patients with a severe fatty infiltration clearly indicating the larger accuracy of the qMRI approach. Mean intramuscular fat fraction was significantly correlated with CSS scale (p≤0.01) and was inversely correlated with MMT score, MFM subscore D1 (p≤0.01) further illustrating the sensitivity of the qMRI approach. Overall, a clustering analysis disclosed three different imaging patterns of muscle involvement for the thighs and the legs which could be related to different stages of the disease and put forth muscles which could be of interest for a subtle investigation of the disease progression and/or the efficiency of any therapeutic strategy.ConclusionThe qMRI provides a sensitive measurement of fat fraction which should also be of high interest to assess disease progression and any therapeutic strategy in FSHD1 patients.