Posterior Cuff Research Articles

Preoperative rotator cuff fatty infiltration and muscle atrophy do not negatively influence outcomes following anatomic total shoulder arthroplasty

BackgroundAnatomic total shoulder arthroplasty (TSA) is an effective surgical option for the treatment of primary glenohumeral osteoarthritis (GHOA) with an intact rotator cuff. While an intact rotator cuff is essential to the success of TSA, little is known about how preoperative rotator cuff muscle quality may impact clinical outcomes. In this study, we sought to determine the effects of rotator cuff fatty infiltration (FI) and muscle atrophy (MA) on clinical outcomes following TSA. MethodsA retrospective review of a prospectively maintained, single-surgeon registry was used to identify patients undergoing TSA for GHOA between April 2015 and March 2020. Patients were included if they had preoperative magnetic resonance imaging available, an intact rotator cuff, and complete preoperative and minimum 2-year postoperative patient-reported outcome measures (PROMs) and active range of motion (ROM) measurements. Preoperative MA and FI of the rotator cuff were assessed on magnetic resonance imaging by measuring muscle cross-sectional area and using the Goutallier classification system, respectively. Pearson’s correlation was used to determine any relationship between MA and clinical outcomes. Univariate analysis was used to compare clinical outcomes of patients with moderate-to-severe FI to those with minimal-to-mild FI. ResultsThere were 163 shoulders from 154 patients with a mean age of 62.5 (standard deviation = 7.4) and a mean follow-up of 2.9 years (standard deviation 1.2) that met inclusion criteria. Rotator cuff muscle area was not correlated with any preoperative or postoperative ROM or PROMs (P > .05). However, the ratio of infraspinatus and teres minor (posterior cuff) to subscapularis muscle area was minimally negatively correlated with change in Single Assessment Numerical Evaluation (r = −0.171, P = .029) and change in internal rotation (r = −0.207, P = .008), although the clinical relevance is unclear. No significant differences in preoperative ROM or PROMs were found between patients with minimal-to-mild and moderate-to-severe FI (P > .05). ConclusionPreoperative rotator cuff muscle volume and FI do not impact clinical outcomes following TSA in patients with GHOA and intact rotator cuffs. TSA remains a viable surgical treatment for individuals with GHOA and an intact rotator cuff, provided the MA and FI are not so severe that a patient may be indicated for another type of treatment.

Methodology for vNOTES Sacrocolpopexy with Transvaginal Mesh Retroperitonealization and Tensioning

Background: Laparoscopy has the potential of making procedures less invasive with a lower complication profile while being more appealing to patients due to ease of recovery and cosmesis. Sacrocolpopexy has traditionally been performed through the abdominal route with limited reports of transvaginal applications. Methods: Our study aims to provide a step-by-step approach to performing a vNOTES sacrocolpopexy with appropriate tensioning and peritoneal coverage of the mesh used based on both cadaveric and live patient experience. This systematic description of a fully laparoscopic transvaginal apical suspension with mesh attachment to the sacrum being completely retroperitoneal and the mesh retroperitoneal and covered at the conclusion of the case. Results: Successful vNOTES Sacrocolpopexy is performed and reproduced, with transvaginal complete peritoneal coverage and tensioning of the mesh. Total vaginal length (TVL) of 9 cm in both live and cadaveric patients. The steps of the procedure include 1. A vNOTES laparoscopic-assisted vaginal hysterectomy is completed. 2. A 0-Prolene suture is attached longitudinally to the sacral arm of a precut (Y) mesh or any single layer Type I polypropylene mesh piece, placed from the sacral arm to the distal edge of the mesh forming a “U” shape with the bottom of the “U” ultimately attaching to the anterior longitudinal ligament. 3. To begin the SCP procedure after completion of the vaginal hysterectomy, dissection of the presacral mesh attachment site begins by entering the retroperitoneal space, slightly right of midline at the level of the ischial spine, lateral to the rectum and medial to the uterosacral ligament. 4. Once the dissection is completed with appropriate exposure of the anterior longitudinal ligament at the sacral promontory, the sacral mesh is attached to the anterior longitudinal ligament at the S1-2 level, ideally with a tacker under direct visualization. 5. Two sutures, one on each side of the tunnel, are placed on the cephalad edge of the sacral peritoneal incision and labeled. After removing the Gelport, two more absorbable sutures are attached to the anterior peritoneum of the anterior vaginal wall in the proximity of the bladder, around 3 cm on each side of the midline. These peritoneal sutures in each of the above two steps will later be tied together to help cover the arms of the mesh. 6. Before mesh arm attachment, each area on the anterior and posterior vaginal walls is dissected off respective tissue (bladder and perineal body/rectovaginal fascia) and then everted for mesh attachment. 7. Both anterior and posterior mesh pieces are sutured to their respective vaginal walls with six interrupted sutures. Each mesh arm will have several centimeters of mesh freely hanging off both anterior and posterior cuff edges. These edges can be trimmed to 2 cm past the vaginal cuff edge. 8. All three pieces of mesh are stacked together and serially threaded from anterior mesh to posterior mesh, ensuring each mesh piece remains aligned (Figure 1). Each U suture is then passed through the free ends of the anterior and posterior mesh pieces and then secured with a hemostat. The cut edges of the suture can either be aligned at the back of the posterior arm to permit retroperitonealization of the knot or placement at the vaginal apex abutting the vaginal cuff. 9. Peritoneal closure is achieved by tying a posterior tunnel suture to each respective anterior vaginal wall suture at each lateral edge of the tunnel incision. 10. The vaginal cuff closure begins with a Vicryl suture anchored at the patient’s right forniceal edge running it to midline while anchoring another suture at the left forniceal edge to permit the surgeon to tension the vaginal apex appropriately. 11. Mesh tensioning is achieved by placing a single digit through the remaining space left in the tunnel incision. A knot using the Prolene suture securing the overlapping mesh is tied extracorporeally and pushed through the vaginal cuff to mobilize the mesh crux cephalad, thus elevating the vaginal apex towards the sacrum. The elevation of this knot guides the vaginal length. 12. The remainder of the vaginal cuff is then closed while avoiding incorporation of the mesh into the suture line (the ideal distance from mesh Y-junction to cuff is 1-2cm). Conclusion: By describing an innovative and reproducible technique to perform vNOTES sacrocolpopexy based on cadaveric and live patient experience, we successfully demonstrate how to perform a laparoscopic transvaginal apical suspension with mesh attachment to the sacrum through retroperitoneal placement. The vNOTES approach for sacrocolpopexy may offer a viable alternative to the transabdominal approach for candidates with difficult transabdominal access while avoiding trocar injuries and reducing surgical costs.

Effect of subscapularis repair on joint contact forces based on degree of posterior-superior rotator cuff tear severity in reverse shoulder arthroplasty.

Massive irreparable rotator cuff tears (RCTs) affect the clinical outcomes of reverse shoulder arthroplasty (RSA). However, the effects of subscapularis repair on the outcomes of RSA, based on the degree of posterior-superior RCTs, are unclear. This study aimed to examine the effect of subscapularis repair on three-dimensional joint contact forces (JCFs) based on the degree of posterior-superior RCT severity in RSA. Ten human in vivo experimental data were used as input to the musculoskeletal model. A six-degrees-of-freedom (DOF) anatomical shoulder model was developed and validated against three-dimensional JCFs. The 6-DOF musculoskeletal shoulder model of RSA was then developed by importing the reverse shoulder implant into the validated anatomical shoulder model. Based on the various types of posterior-superior RCT severity, inverse dynamic simulations of subscapularis-torn and subscapularis-repaired models of RSA were performed: from isolated supraspinatus tears to partial or massive tears of the infraspinatus and teres minor. The intact rotator cuff model of RSA was also simulated for comparison with the different types of models. Our results showed that the more posterior-superior RCTs progressed in RSA, the more superior JCFs were observed at 90°, 105°, and 120° abduction in the subscapularis-torn model. However, subscapularis repair decreased the superior JCF at those angles sufficiently. In addition, the teres minor muscle-tendon force increased as infraspinatus bundle tears progressed in both the subscapularis-torn and -repaired models, in order to compensate for the reduced force during abduction. However, the teres minor muscle-tendon force was not as high as that of the infraspinatus muscle-tendon, which could result in muscle force imbalance between repaired subscapularis and teres minor. Therefore, our results suggest that repairing the subscapularis and the repairable infraspinatus during RSA can improve glenohumeral joint stability in the superior-inferior direction by restoring muscle force balance between the anterior cuff (i.e., subscapularis) and posterior cuff (i.e., infraspinatus and teres minor). The findings of this study can help clinician decide whether to repair the rotator cuff during RSA to enhance joint stability.

Biomechanical Consequences of Glenoid and Humeral Lateralization in Reverse Total Shoulder Arthroplasty.

The objective of our study was to quantify the biomechanical effectiveness of lateralization in RTSA with respect to glenoid and humeral component configurations. Eight cadaveric shoulders were tested in a custom shoulder testing system. Three parameters, including the glenosphere thickness, humeral tray offset and insert thickness, were assessed by implanting eight configurations on each specimen. Humeral position, maximum internal rotation, and maximum external rotation (ER) before impingement were quantified at 0°- and 30°- glenohumeral abduction. The adduction angle at which the humeral component contacted the inferior scapular neck and the abduction angle where acromial notching occurred were also measured. The simulated active range of motion, including ER and abduction capability, was tested by increasing the load applied to the remaining posterior cuff and middle deltoid, respectively. Stability was evaluated by the forces that induced anterior dislocation at 30° abduction. The thicker glenosphere affected only lateralization, whereas the centric humeral tray and thicker insert significantly affected humeral lateralization and distalization simultaneously. Greater adduction and ER angles were found in more lateralized humerus. A significant positive correlation between humeral lateralization and ER capability was observed; however, lateralization did not significantly improve implant stability in this cadaveric testing system. Lateralization is achievable at both the glenoid and humeral sides but has different effects, therefore lateralized implant options should be selected according to patients' needs. Lateralization is an effective strategy for reducing adduction notching while increasing ER capability. Thicker glenospheres only affected humeral lateralization. The centric humeral tray would be selected for less distalization to avoid over-lengthening, whereas an eccentric humeral tray is the most effective for distalization and medialization in reducing abduction notching to the acromion and for patients with pseudoparalysis.

What's New in Sports Medicine.

What's New in Sports Medicine.

8387 Instructional Video on Tandem Vaginal Cuff Closure

<h3>Study Objective</h3> To demonstrate the steps of tandem vaginal cuff closure, outline specific movements of the surgeon and assistant, and provide suggestions for efficient closure. <h3>Design</h3> Instructional Video. <h3>Setting</h3> Operating room of large academic hospital. <h3>Patients or Participants</h3> Single patient undergoing a laparoscopic vaginal cuff closure at the time of hysterectomy. <h3>Interventions</h3> In this technique, two surgeons close the vaginal cuff at the time of hysterectomy through an umbilical port for the 5mm camera and two 5mm lateral ports for instrumentation. This eliminates the need for fascial closure and improves cosmesis. The surgeon stands at the patient's left and holds the needle driver in the right hand. The surgeon positions the needle correctly to facilitate an efficient and effective cuff closure starting from the patient's right and proceeding toward the left. The direction of closure is from posterior to anterior. At least 5mm of vaginal mucosa is incorporated into each bite, and uterosacral and cardinal ligaments are incorporated bilaterally to provide support. A key component is to push the needle through the tissue, with over supination of the surgeon's wrist while lifting the needle cephalad. This over-supination allows better visualization and provides the correct angle for needle reloading. The assistant, standing on the patient's right, provides visualization, places the loop of the barbed suture over the needle, and manipulates the anterior or posterior cuff over the needle. <h3>Measurements and Main Results</h3> Complete and efficient vaginal cuff closure with incorporation of uterosacral and cardinal ligaments for support. <h3>Conclusion</h3> With the use of two skilled surgeons, we demonstrate the efficient movements required to carry out a tandem vaginal cuff closure.

Biomechanical comparison of 3 latissimus dorsi transfer sites for reverse total shoulder arthroplasty in the absence of teres minor.

Reverse total shoulder arthroplasty is often performed to treat rotator cuff tear arthropathy with irreparable rotator cuff tears. Patients with full-thickness tears involving the posterior cuff and teres minor specifically lose active external rotation of the humerus, limiting activities of daily living. A latissimus dorsi transfer has been described as one potential solution, but few studies have compared different latissimus dorsi transfer sites. This study assesses the biomechanics of 3 latissimus dorsi transfer sites, examining external rotation, deltoid muscle forces, and force across the glenoid for specific activities. The Newcastle Shoulder Model was modified to include a Delta III reverse shoulder arthroplasty and was used to model the effects of 3 latissimus dorsi transfer sites-anterior, posterolateral, and posterodistal-in the setting of teres minor deficiency. The latissimus dorsi was represented by 5 muscle elements approximating anatomic fascicle divisions. Kinematic data sets representing common activities were input into the model, allowing calculation of muscle forces and glenoid loads. Each of the 3 latissimus dorsi transfer sites demonstrated a change of moment arm from internal to external rotation with increased magnitude. Average maximum deltoid muscle forces and glenoid loading across all motions decreased for each of the 3 transfer sites, with the greatest decreased force noted for the posterior deltoid. This decrease in deltoid force and glenoid loading was significantly greater with the anterior and posterolateral transfer sites, relative to the posterodistal site. Latissimus dorsi transfer to all 3 sites in the setting of reverse total shoulder arthroplasty and posterior rotator cuff deficiency resulted in large external rotation moment arms. The transferred latissimus dorsi shared the external rotation load and resulted in decreased deltoid forces and glenoid loading with very small differences between the 3 transfer sites. The posterodistal location reduced deltoid force and glenoid loading to a lower degree compared with other sites, but it also showed that it did not alter the tendon length compared with the native shoulder.

Superior Capsular Reconstruction for Irreparable Rotator Cuff Tears: Technique and Associated Considerations

Background: Massive rotator cuff tears lead to superior humeral head translation and may prevent successful repair. Superior capsular reconstruction (SCR) can overcome this by improving the compression and depressor effects of the rotator cuff and joint capsule simultaneously. Indications: SCR is indicated in young, active patients with massive rotator cuff tears or a functional cuff deficiency from a failed previous rotator cuff repair without significant arthritis, articulation of the humeral head with the acromion, or dysfunctional deltoid. Technique Description: During the procedure, repair of the subscapularis is performed using a polydioxanone (PDS) suture shuttling device to pass suture through the subscapularis in an inverted mattress knotless configuration. Posterior infraspinatus tendon fibers are reduced and the tuberosity is abraded and decorticated followed by completion of the partial repair of the posterior cuff. Anchors are placed on the glenoid and articular margins followed by preparation of the dermal allograft with luggage tags medially and perforation laterally. The graft is passed and secured in a double row configuration laterally with apposition of the graft to the remnant, repaired rotator cuff posteriorly. Results: Passive range of motion (ROM) is begun at week 4, followed by progressive active ROM at weeks 6 to 12, and advancement of full ROM and advanced strengthening begun at 3 months. With SCR, a patient can expect maximal strength and function to be regained at 1 year postoperatively. Significant clinical improvement following SCR has been seen in visual analog scale (VAS) and American Shoulder and Elbow Surgeons Shoulder Score (ASES) scores for most patients, although there is a varied degree of return to sport following this procedure. Discussion/Conclusion: Clinical evidence suggests that SCR is a beneficial therapeutic intervention for short to medium term outcomes in younger patients with massive, irreparable rotator cuff tears. More studies are needed to identify the optimal thickness of the graft.

Laparoscopic Complete Excision of the Posterior Muscular Cuff: Technique Refinements and Comparison With Stepwise Gradient Muscular Cuff Cutting for Hirschsprung Disease.

ObjectivesOur institution had modified the Soave pull-through procedure using laparoscopic stepwise gradient muscular cuff cutting (LSGC) for Hirschsprung disease (HSCR). However, we found that a few children still suffered from obstructive symptoms and enterocolitis during the follow-up. Previous studies suggested that these symptoms might be caused by the retained muscular cuff. The purpose of this study was to employ a modified procedure of laparoscopic complete excision of the posterior muscular cuff (LCEPC) for HSCR and compare it with the laparoscopic stepwise gradient cutting muscular cuff (LSGC) procedure.MethodsOur institution records of 83 patients with classic form HSCR who underwent LSGC or LCEPC between August 2014 and July 2018 at the Pediatric Surgery Department of Zunyi Medical University (Zunyi, China) were carefully reviewed (LSGC, n = 52; LCEPC, n = 31). In the present study, we compared the postoperative complications and defecation functions of the two groups. All patients were followed-up (1–5 years, with an average of 2 years).ResultsThere were no differences regarding the operation time and the length of hospitalization between groups, while the anal dissection time in the LCEPC group (22.4 ± 4.8 min) was shorter than that of the LSGC group (45.5 ± 7.5 min) (p < 0.001). The postoperative complication of soiling was significantly increased in six patients (19.4%) in the LCEPC group compared with two patients (3.8%) in the LSGC group (p = 0.021). However, the total incidence of enterocolitis (two patients, 6.5%) was significantly decreased in the LCEPC group compared with the LSGC group (12 patients, 23.1 %) (p = 0.050). For anastomotic stricture, muscular cuff infection, and constipation, there were no significant differences between the two groups. No patients experienced bladder paralysis and incontinence postoperatively in this study. Anorectal manometries presented that the anorectal resting pressure was significantly lower in the LCEPC group (14.8 ± 2.7 mmHg) than the LSGC group (22.0 ± 3.8 mmHg), (p < 0.001).ConclusionThe laparoscopic complete excision of the posterior muscular cuff method was demonstrated as safe and efficient, with a decrease in the incidence of enterocolitis, although it may increase the number of soiling incidents in the short period post-surgery owing to a dissected partial internal anal sphincter.

CT-based volumetric assessment of rotator cuff muscle in shoulder arthroplasty preoperative planning.

AimsThe aim of this study was to describe a quantitative 3D CT method to measure rotator cuff muscle volume, atrophy, and balance in healthy controls and in three pathological shoulder cohorts.MethodsIn all, 102 CT scans were included in the analysis: 46 healthy, 21 cuff tear arthropathy (CTA), 18 irreparable rotator cuff tear (IRCT), and 17 primary osteoarthritis (OA). The four rotator cuff muscles were manually segmented and their volume, including intramuscular fat, was calculated. The normalized volume (NV) of each muscle was calculated by dividing muscle volume to the patient’s scapular bone volume. Muscle volume and percentage of muscle atrophy were compared between muscles and between cohorts.ResultsRotator cuff muscle volume was significantly decreased in patients with OA, CTA, and IRCT compared to healthy patients (p < 0.0001). Atrophy was comparable for all muscles between CTA, IRCT, and OA patients, except for the supraspinatus, which was significantly more atrophied in CTA and IRCT (p = 0.002). In healthy shoulders, the anterior cuff represented 45% of the entire cuff, while the posterior cuff represented 40%. A similar partition between anterior and posterior cuff was also found in both CTA and IRCT patients. However, in OA patients, the relative volume of the anterior (42%) and posterior cuff (45%) were similar.ConclusionThis study shows that rotator cuff muscle volume is significantly decreased in patients with OA, CTA, or IRCT compared to healthy patients, but that only minimal differences can be observed between the different pathological groups. This suggests that the influence of rotator cuff muscle volume and atrophy (including intramuscular fat) as an independent factor of outcome may be overestimated.Cite this article: Bone Jt Open 2021;2(7):552–561.

CORR Insights®: Imbalance in Axial-plane Rotator Cuff Fatty Infiltration in Posteriorly Worn Glenoids in Primary Glenohumeral Osteoarthritis: An MRI-based Study.

CORR Insights®: Imbalance in Axial-plane Rotator Cuff Fatty Infiltration in Posteriorly Worn Glenoids in Primary Glenohumeral Osteoarthritis: An MRI-based Study.

Three-dimensional kinematic features in large and massive rotator cuff tears with pseudoparesis

Although massive rotator cuff tears occasionally lead to severe impairment of shoulder function, the criteria for losing the ability to elevate the arm are unclear. This study aimed to analyze the features of both tear size and 3-dimensional (3D) shoulder kinematics that correspondto the loss of the ability to elevate the arm in patients with large and massive rotator cuff tears. We prospectively enrolled patients with rotator cuff tears, including the supraspinatusand more than half of the subscapularis or more than two-thirds of the infraspinatus, without severe pain. A total of 13 patients (15 shoulders) were divided into 2 groups: 9 shoulders in the pseudoparesis (P) group and 6 shoulders in the non-pseudoparesis (NP) group. Fluoroscopic images were collected during active scapular-plane elevation, and 3D shoulder kinematics was analyzed using 2-dimensional-3D registration techniques. The radiographic findings and 3D kinematic results were compared between the groups. The correlation between tear size and 3D kinematics was also investigated. The most superior position of the humeral head center was significantly higher in the P group (6.7 ± 3.0 mm in P group vs. 3.6 ± 1.3 mm in NP group, P = .0321). Superior migration, which was defined as the most superior position > 5 mm, was significantly more frequent in the P group (7 shoulders and 1 shoulder in the P and NP groups, respectively; P = .0201). Thoracohumeral external rotation was significantly smaller in the P group (16° ± 31° in P group vs. 91° ± 21° in NP group, P < .0001). The total tear size and the tear sizes of the anterior and posterior rotator cuffs were significantly correlated with the superior (r = 0.68, P = .0056), anterior (r = 0.68, P = .0058), and posterior (r = -0.80, P = .0004) positions of the humeral head center. The tear size of the posterior rotator cuff also tended to be correlated with glenohumeralexternal rotation (r = -0.48, P = .0719). Anterior and posterior rotator cuff tears cause significant superior and anteroposterior translations of the humeral head, and posterior cuff tears may lead to loss of glenohumeral external rotation. With these abnormal kinematics, superior migration and loss of thoracohumeral external rotation were identified as features of pseudoparesis.

Glenoid Retroversion Associates With Asymmetric Rotator Cuff Muscle Atrophy in Those With Walch B-type Glenohumeral Osteoarthritis.

Our purpose was to determine whether glenoid retroversion associates with asymmetric rotator cuff muscle atrophy in eccentric glenohumeral osteoarthritis (GHOA) and if this asymmetry is worsening of GHOA-related atrophy. Two groups of shoulder magnetic resonance images were studied: patients older than 50 years without a rotator cuff tear or GHOA (control group) and patients preoperative to anatomic total shoulder arthroplasty (GHOA group). Retroversion and rotator cuff muscle cross-sectional areas were measured using reliable and accurate techniques. Proportional muscle areas were created by dividing by total cuff area to correct for differences in overall patient size. Walch grades were assigned via consensus. The control group consisted of 102 patients and the GHOA cohort consisted of 141 patients. Within the eccentric GHOA group, retroversion associated with relative increasing supraspinatus (r = 0.268, P = 0.035), increasing infraspinatus (r = 0.273, P = 0.032), and decreasing subscapularis areas (r = -0.343, P = 0.006). However, the combined GHOA group had a significantly higher relative subscapularis area than the control group (P = 0.026). In the eccentric GHOA, increasing retroversion is associated with increasing volume of the posterior cuff relative to the anterior cuff muscles, which is a reversal of the asymmetric increasing volume of the anterior cuff relative to the posterior cuff muscles seen with concentric GHOA. Diagnostic, level III.

Do Outcomes of Arthroscopic Subscapularis Tendon Repairs Depend on Rotator Cuff Fatty Infiltration?

Background:Rotator cuff fatty infiltration has been correlated with poorer radiographic and clinical outcomes in supraspinatus and infraspinatus tendon repairs, but this has not been well-studied in subscapularis tendon repairs.Purpose:To evaluate the influence of preoperative rotator cuff fatty infiltration on postoperative outcomes for patients undergoing arthroscopic subscapularis tendon repair.Study Design:Cohort study; Level of evidence, 3.Methods:Patients who underwent arthroscopic subscapularis repair between 2010 and 2016 were retrospectively identified, and demographic data and surgical findings were recorded. The extent of fatty infiltration was determined on preoperative magnetic resonance imaging by the Fuchs modification of the Goutallier classification. At the most recent follow-up, patients completed the Patient-Reported Outcomes Measurement Information System for Upper Extremity (PROMIS-UE) computer adaptive test and a postoperative visual analog scale for pain. The distribution of fatty infiltration was compared between patients undergoing subscapularis tendon repair versus subscapularis tendon repair combined with a posterior cuff repair. Outcomes were compared for patients using Goutallier grade 0-1 versus grade ≥2 changes in each rotator cuff muscle. Multivariate linear regression analysis was performed to evaluate the influence of muscle quality, as well as demographic factors, on PROMIS-UE scores. Significance was defined as P < .05.Results:There were 140 shoulders included (mean age, 61.8 years; 42.1% female; mean follow-up, 51.7 months). The prevalence of Goutallier grade 2 changes or higher was significantly greater in patients with multitendon repair relative to isolated subscapularis tendon repair. For the overall group of all patients undergoing subscapularis tendon repair, whether in isolation or as part of a multitendon repair, PROMIS-UE scores were significantly lower for patients with infraspinatus muscle grade 2 or higher Goutallier changes relative to grade 0 or 1. After adjustment for age, body mass index, patient sex, and fatty infiltration in other rotator cuff muscles, poor infraspinatus muscle quality remained the only significant predictor for lower PROMIS-UE scores.Conclusion:Patients undergoing arthroscopic subscapularis tendon repair with poor infraspinatus muscle quality had worse patient-reported outcomes. This was true whether subscapularis tendon repair was isolated or was performed in conjunction with supraspinatus and infraspinatus tendon repairs.

Angle of approach to the superior rotator cuff of arthroscopic instruments depends on the acromial morphology: an experimental study in 3D printed human shoulders

BackgroundPortal placement is a key factor for the success of arthroscopic procedures, particularly in rotator cuff repair. We hypothesize that the acromial anatomy may strongly determine the position of the shoulder bony landmarks and limit the surgeon’s freedom to position the arthroscopic approaches in direction towards the acromion. The purpose of this study was to analyze the relation between different acromial shapes and the freedom of movement of arthroscopic instruments relative to the rotator cuff from standardized arthroscopic portals in a laboratory study on 3D shoulder models.Methods3D models of shoulders with a broad range of different acromial shapes were printed using CT and MRI scans. Angles from the portals to defined points on the rotator cuff and the supraglenoid tubercle were measured. In conventional radiographs, the critical shoulder angle, the scapular body acromial angle, and the glenoid acromial angle were measured and compared with the measured angles to the rotator cuff.ResultsThere was a large variation of angles of approach of instruments to the rotator cuff between the seven shoulders for each portal. From the joint line portal and the posterior edge portal, the biggest angles were measured to the posterior cuff. From the intermediate portal, the angles were largest to the intermediate rotator cuff and from the anterior portals to the anterior cuff. To the supraglenoid tubercle, best access was from anterior. For all portals, there was a big correlation between the glenoid acromial angle and the scapular body acromial angle with the angles of approach to the tendon and especially to the supraglenoid tubercle.ConclusionThe access to the rotator cuff from almost every portal is influenced by the acromial shape. As hypothesized, a small (small GAA) and flat (big SBAA) acromion provide an easier approach to the rotator cuff from almost every portal. Therefore, it may severely influence the instruments maneuverability.

Association Between Rotator Cuff Muscle Size and Glenoid Deformity in Primary Glenohumeral Osteoarthritis.

Although glenoid morphology has been associated with fatty infiltration of the rotator cuff in arthritic shoulders, the association of rotator cuff muscle area with specific patterns of glenoid wear has not been studied. The purpose of our study was to assess the associations of glenoid deformity in primary glenohumeral osteoarthritis and rotator cuff muscle area. A retrospective study of 370 computed tomographic (CT) scans of osteoarthritic shoulders was performed. Glenoid deformity according to the modified Walch classification was determined, and retroversion, inclination, and humeral-head subluxation were calculated using automated 3-dimensional software. Rotator cuff muscle area was measured on sagittal CT scan reconstructions. A ratio of the area of the posterior rotator cuff muscles to the subscapularis was calculated to approximate axial plane potential force imbalance. Univariate and multivariate analyses to determine associations with glenoid bone deformity and rotator cuff measurements were performed. Patient age and sex were significantly related to cuff muscle area across glenoid types. Multivariate analysis did not find significant differences in individual rotator cuff cross-sectional areas across glenoid types, with the exception of a larger supraspinatus area in Type-B2 glenoids compared with Type-A glenoids (odds ratio [OR], 1.5; p = 0.04). An increased ratio of the posterior cuff area to the subscapularis area was associated with increased odds of a Type-B2 deformity (OR, 1.3; p = 0.002). Similarly, an increase in this ratio was significantly associated with increased glenoid retroversion (beta = 0.92; p = 0.01) and humeral-head subluxation (beta = 1.48; p = 0.001). Within the Type-B glenoids, only posterior humeral subluxation was related to the ratio of the posterior cuff to the subscapularis (beta = 1.15; p = 0.001). Age and sex are significantly associated with cuff muscle area in arthritic shoulders. Asymmetric glenoid wear and humeral-head subluxation in osteoarthritis are associated with asymmetric atrophy within the rotator cuff transverse plane. Increased posterior rotator cuff muscle area compared with anterior rotator cuff muscle area is associated with greater posterior glenoid wear and subluxation. It is unclear if the results are causative or associative; further research is required to clarify the relationship. Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Effect of short-term cold-water immersion on muscle pain sensitivity in elite track cyclists

ObjectiveTo determine the effect of short-term cold-water immersion (CWI) on muscle pain sensitivity after maximal anaerobic power training in track cyclists. DesignRepeated measures. SettingUniversity Laboratory. Participants12 elite sprint track cyclists (age 24,75 ± 4,23 years). Main outcome measuresPPT measurements were made on dominant lower extremity (right) in 20 reference points, including anterior thigh muscles, posterior thigh muscles and posterior cuff muscles. PPT levels were measured: 1) before workout, 2) immediately after workout, but before CWI 3) 1 h after CWI and 4) 12 h after CWI. Mean PPT values for each muscle group per participant were calculated for further statistical analysis. ResultsThe average PPT for anterior thigh muscles decreased significantly after effort (p = 0.001) and increased significantly 1 h after CWI (p = 0.048). In posterior thigh muscles PPT decreased significantly after effort (p = 0.014) and increased significantly 1 h and 12 h after CWI (p = 0.045 and p = 0.25 respectively). However, in posterior cuff muscles PPT decreased only after effort (p = 0.001). ConclusionsShort-term repeated sprint exercise appears to affect PPT in track cyclists. This study have reported that CWI in 5 °C for 5 min have had a beneficial effect in minimizing PPT 1 h post repeated maximal sprint training.

Allograft-Prosthetic Composite Reconstruction for Massive Proximal Humeral Bone Loss in Reverse Shoulder Arthroplasty.

Allograft-prosthetic composite (APC) reconstruction of the humerus represents an appealing surgical technique when implantation of a reverse prosthesis is considered in the setting of substantial proximal humeral bone loss1-4. Humeral APCs have been successfully performed in the past with a non-reverse shoulder prosthesis4,5. Reconstruction of the proximal part of the humerus with an allograft provides adequate support and fixation for the humeral component, allows restoration of length and lateral offset, and provides an opportunity for soft-tissue reattachment when needed. On the basis of the available peer-reviewed data, healing at the allograft-host junction is reliable, and complication rates, including instability, are relatively low3,6. Once the glenoid reverse component has been implanted, a proximal humeral allograft is prepared to receive the humeral component of a reverse arthroplasty. The allograft is procured by our institutional bone and tissue bank, purchased from a number of vendors. The graft is selected after review of the description and radiographs provided by the vendor. The priority is to obtain a graft with sufficient length and soft tissues attached. If possible, the graft selected should have a diameter close to the diameter of the humerus of the recipient. The desired allograft length is selected on the basis of preoperative planning and intraoperative measurements, and the distal portion of the allograft is resected accordingly. Depending on the length of the defect, host bone quality, and surgeon preferences, the humeral component may or may not bypass the host-graft junction. The stem bypasses the host-graft junction for shorter APCs, as well as when the bone quality of the native humerus is compromised. Cemented fixation into the graft is universally used. Compression plating is used for graft-to-host fixation, supplemented by implantation of the stem across the junction in selected cases. Care is taken during the freehand cut to obtain optimal contact and compression. Once the ideal humeral bearing thickness has been selected, the polyethylene bearing is implanted and the joint relocated. If the posterior cuff can be repaired to cuff allograft, sutures are placed prior to relocation and are tied after relocation. Other musculotendinous units, such as the deltoid or pectoralis major, are repaired to the allograft if needed. Implantation of a reverse prosthesis with a proximal humeral metal body (a so-called tumor prosthesis) is the main alternative to proximal humeral APC reconstruction. In patients with shorter defects, adequate soft-tissue tension may be obtained by implanting a glenosphere with a large inferior eccentricity and cementing the humeral component in a more proximal position than is usually performed. Alternatively, when implantation of the glenoid component of a reverse prosthesis is not possible, a hemiarthroplasty-APC construct may be performed1,4,5,7-10, adding a synthetic sleeve such as an aortic Dacron graft to enhance soft-tissue stability if needed. When reverse arthroplasty is performed in the setting of substantial humeral bone loss, the humeral component may be poorly supported and at risk for loosening. In addition, the absence of proximal humeral bone stock may lead to shortening and/or loss of lateral offset. Finally, the posterosuperior cuff, subscapularis, deltoid, and pectoralis tendons may remain detached. The potential consequences of humeral bone loss in the setting of reverse arthroplasty include humeral loosening, dislocation, and poor active motion (particularly poor active elevation). Allograft reconstruction of the proximal part of the humerus provides an opportunity for better support of the component, restoration of humeral length and lateral offset, and attachment sites for the musculotendinous structures around the shoulder, if needed.

Safe Zone Technique Improves Suture Placement During Remplissage

Objectives:Recent studies have raised concern over the accuracy of suture passage into the infraspinatus tendon during remplissage. Our purpose was to evaluate the accuracy of suture passage during remplissage and identify surface landmarks to improve accuracy. Our secondary purpose was to validate the use of these identified landmarks to improve accuracy of suture passage through the infraspinatus tendon.Methods:12 cadaveric specimens were used. In the first 6 specimens (control group), standard arthroscopic remplissage was performed. Specimens were dissected to quantify the location of suture passage in reference to the posterolateral acromion (PLA) and to identify the location of posterior cuff penetration. After analyzing the control group specimens a “safe zone” (SZ) was identified to improve accuracy of passage and increase infraspinatus tendon penetration. For final 6 specimens, the safe zone technique was utilized for suture passage during arthroscopic remplissage. Specimens were again dissected to analyze the accuracy of suture passage and location of penetration. Results were compared to the control group.Results:For the control group, 24 sutures were passed. 25.0% (6/24) were passed through the infraspinatus tendon, and 75%(18/75) were through the teres or infraspinatus muscle or MTJ. Sutures passage through the infraspinatus were an average of 25±5.4 mm distal to the PLA, while teres minor sutures were an average of 35.8±5.7mm distal to the PLA. If passes were less than 3 cm distal to the PLA, there was a significantly higher rate of infraspinatus tendon penetration (odds ratio[OR]=25 ,p<0.01). Sutures passing through muscle and MTJ were significantly more medial than those passing through tendon, at an average 8.1±5.1mm lateral to the PLA compared to 14.5±5.5mm (p<0.02). Passes were more likely to be in tendon, rather than muscle or MTJ if greater than 1 cm lateral to the PLA (p=0.013). The safe zone was defined as passing all tenodesis sutures greater than 1 cm lateral and less then 3cm distal to the PLA. Utilizing this technique, 24 sutures were also passed arthroscopically in the remaining 6 specimens. 83.3% (20/24) were in the infraspinatus tendon, which was significantly improved from the control group (p<0.01). Only, 4.2% (1/24) of attempted passes in the SZ group passed through the muscle or MTJ which was also significantly improved from the control group (p<0.01). Prevention of over-medialization significantly improved using the SZ as represented by both anchors having suture passage significantly more lateral (6-10mm) than the control group (p<0.01). There was also an improvement in the precision of suture passes with utilization of the SZ, as overall precision (SD) improved in 75% of sutures passes.Conclusion:We found standard remplissage suture passage was inaccurate with only 25% of sutures penetrating the infraspinatus tendon. We recommend utilization of the “safe zone” technique, which consists of passing sutures 1 cm lateral and within 3 cm distal of the PLA. Furthermore this study validates that the “safe zone” technique, demonstrating significant improvement in accuracy of suture passage into the infraspinatus tendon and prevented over-medialization with muscle penetration. The safe zone technique provides a reproducible method that may prove useful to prevent previously reported complications associated with arthroscopic remplissage.

Latissimus Dorsi Transfer in Posterior Irreparable Rotator Cuff Tears.

Background:Massive rotator cuff tears pose a difficult and complex challenge even for the experienced surgeon; inability to repair these tears by conventional means designates them as irreparable, while management becomes quite taxing. Several operative options have been suggested for the management of such lesions with varying degrees of success, while it is imperative to match patient demands and expectations to the predicted outcome.Methods:Research articles are examined and key concepts are discussed, in order to provide an evidence based review of the available literature. The anatomy and pathomechanics along with the indications, contraindications and surgical techniques are reported.Results:Transfer of the Latissimus dorsi has been used with success to restore shoulder function in deficits of the posterior rotator cuff. Although it can be used in a variety of settings, the ideal patient for a Latissimus dorsi tendon transfer is a young and active individual, with no glenohumeral osteoarthritis that has a severe disability and weakness related to an irreparable posterior cuff tear.Conclusion:Tendon transfers have proved to be a successful treatment option in salvaging this difficult problem, providing pain relief and restoring shoulder function. Despite the excellent functional outcomes and pain suppression following operation, a variety of factors may affect the outcome; thus making indications and preoperative assessment a valuable component.