Irreducible Posterior Shoulder Dislocation With Concomitant Fracture of Both the Greater and Lesser Tuberosity: An Extremely Rare Shoulder Injury

Posterior shoulder dislocation is a relatively rare injury representing only 5% of all shoulder dislocations. It is usually the result of a high-energy trauma or an epileptic seizure. Diagnosis is challenging with half of these injuries missed in the emergency room (ER). Often the dislocation is accompanied by a lesser tuberosity fracture as a result of the impact between the posterior glenoid and the proximal humerus. Additionally, fractures of the greater tuberosity or even the metaphysis are extremely rare, and their treatment remains challenging. We present a rare case of posterior locked shoulder dislocation with a concomitant lesser and greater tuberosity fracture in a young patient. A 29-year-old male was brought to the ER following a motor vehicle accident. The patient reported significant pain and inability to move his left shoulder. The arm was locked in an internal rotation and was neurovascularly intact. Simple radiographs revealed a locked posterior dislocation with fractures of both the lesser and greater tuberosity. The CT scan confirmed the fracture pattern and excluded metaphyseal fracture. Surgical treatment was decided. Under general anesthesia and a classic thoracodeltoid approach, both tuberosities were recognized and the dislocation was gently reduced. Fixation of the tuberosities with an anatomic plate and Ethibond No. 5 sutures was performed. He was discharged the next day with a 30-degree abduction sling cast. He was instructed to perform passive shoulder and scapula exercises once a day. After one month, the sling was removed and active elevation and rotation exercises were started. Plane X-rays were performed at one, six, and twelve months. The reduction remained stable and the patient recovered full range of motion with a slight loss of external rotation (10 degrees) compared to the contralateral limb. He returned to his previous activities without any complications. Posterior shoulder dislocations with additional fractures of the tuberosities are rare and severe injuries requiring open surgery as the humeral head may remain locked prohibiting closed reduction. Even after the reduction, the stable fixation of the tuberosities is crucial for shoulder stability and postoperative clinical and functional results.

Greater tuberosity morphology is altered in individuals with symptomatic isolated supraspinatus tendon tears

BACKGROUND

In the presence of an isolated supraspinatus tear, the force applied to the greater tuberosity is reduced, which may lead to bony morphologic changes. Thus, diagnostic or surgical identification of landmarks to properly repair the torn tendon might be difficult if the anatomy of the greater tuberosity is altered. The objectives of the study were to assess the presence of the superior, middle, and inferior facets of the greater tuberosity in individuals with symptomatic isolated supraspinatus tendon tears and the associations between tear size, tear location and presence of each facet.

METHODS

Thirty-seven individuals with symptomatic isolated supraspinatus tendon tears were recruited to participate in the study. Individuals underwent a high-resolution computed tomography scan of the involved shoulder and images were segmented to generate subject specific models of each humerus. The vertices comprising each facet were identified; however, if even a single vertex comprising the facet was missing, the facet was considered altered. Percentage agreement for correctly identifying the presence of each facet was determined using 2 additional observers and 5 randomly selected humeri. Ultrasonography was performed to assess anterior-posterior (AP) tear size and tear location. Outcome parameters included presence of the superior, middle, and inferior facets; AP tear size; and tear location. Point-biserial correlations were used to determine the associations between AP tear size, tear location, and presence of the superior, middle, and inferior facets.

RESULTS

Supraspinatus tear size and tear location was 13.1 ± 6.1 mm (range, 1.9-28.3 mm) and 2.0 ± 4.4 mm from the posterior edge of the long head of the biceps tendon (range, 0.0-19.0 mm), respectively. Overall, the superior, middle, and inferior facets were not altered in 24.3%, 29.7%, and 45.9% of individuals, respectively. Percentage agreement between observers was 83.4% on average. No associations were found between tear size or tear location and presence of the superior, middle, or inferior facet (P values ranged from .19 to .74).

CONCLUSION

Individuals with symptomatic isolated supraspinatus tears experience significant alterations in the bony morphology of the greater tuberosity that were irrespective of supraspinatus tear size and location. This information is useful for radiologists and orthopedic surgeons as the altered anatomy may influence the ability to identify important anatomic landmarks during diagnostic imaging or surgical procedures.

Microfracture Lateral to the Greater Tuberosity of the Humerus Enhances Tendon-to-Bone Healing in a Rat Rotator Cuff Model

BACKGROUND

Microfracture at the rotator cuff insertion is an established surgical marrow-stimulation technique for enhancing rotator cuff healing. However, the effect of lateralized or medialized microfracture on the insertion is unknown.

PURPOSE

To compare the biomechanical and histologic effects of microfracture at 3 different regions for rotator cuff repair in a rat model.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 72 Sprague-Dawley rats with bilateral supraspinatus tendon insertion detachment were allocated into 4 groups with 4 different interventions: no microfracture at the humeral head as a control group (Con), traditional microfracture at the footprint area (MFA), and medialized microfracture to the footprint area (MMFA) on the articular surface of the humerus or lateralized microfracture to the footprint area at the greater tuberosity (LMFA). All underwent immediate repair. Tendon-to-bone healing was assessed by biomechanical and histologic tests 4 and 8 weeks postoperation.

RESULTS

At 4 weeks, the LMFA group showed a significantly superior failure load compared with the other groups (all P < .05). The LMFA and MFA groups showed significantly superior stiffness compared with the Con and MMFA groups (all P < .01). At 8 weeks, superior failure load and stiffness were observed in the LMFA group compared with the control group (all P < .05). Histologic examination revealed that the LMFA group had superior collagen composition and tendon-to-bone maturation at the interface at 4 and 8 weeks compared with the Con group (all P < .05).

CONCLUSION

Lateralized microfracture at the greater tuberosity improved the histologic quality of repair tissue and biomechanical strength at the tendon-to-bone insertion after rotator cuff repair in a rat model.

CLINICAL RELEVANCE

Microfracture lateral to the footprint area might be a better way to enhance rotator cuff healing clinically.

Post-Operative Greater Tuberosity Resorption or Malreduction Is Associated with Poor Prognostic Outcomes in Patients with Proximal Humeral Fractures Treated Operatively-A Single-Center Retrospective Cohort Study

(1) Background: Proximal humerus fractures can be a debilitating condition if not properly treated. These fracture patterns are varied and differ in every patient. Functional outcomes may be determined by the integrity of the shoulder girdle involving the rotator cuff insertion. The post-operative resorption or malreduction of the greater tuberosity (GT) is an important factor contributing to the poor functional outcome of a patient. Thus, we intend to evaluate the cause-and-effect relationship between GT complications and clinical prognosis and outcomes. (2) Methods: A single-center retrospective comparative study was performed to evaluate the functional outcomes of patients undergoing operative fixation for this injury. A total of 387 consecutive cases treated operatively from 2019-2021 were included for analysis. (3) Results: 94 cases fulfilled our criteria for analysis. A matched-group comparison of 19 patients each was performed to compare demographics, post-operative fracture characteristics and clinical outcomes. (4) Conclusions: The resorption or malreduction of the GT contributes greatly to the prognostic outcome in patients treated with open reduction and internal fixation (ORIF) surgery. In our demographic study, obesity is another contributing factor affecting the parameters of post-operative reduction in proximal humerus fractures. Appropriate surgical planning and post-operative multidisciplinary care must be taken into consideration to attain a satisfactory prognostic outcome.

Use of electrocautery devices for suture passage through the greater tuberosity: a biomechanical study

BACKGROUND

The use of electrocautery to facilitate passage of a suture needle through bone without the aid of a drill or burr is a novel technique that has potential utility in orthopedic procedures, but there is a scarcity of research to support its utility. The specific aims of this cadaveric biomechanical study were to evaluate (1) the axial force reduction during suture passage using electrocautery when applied to rotator cuff repair, (2) the temperature change caused while using electrocautery, and (3) the failure loads and failure modes of this technique.

METHODS

Five matched pairs of fresh frozen humeri were used, classified into 2 groups: with electrocautery on needle (study group) and without electrocautery on needle (control group). Four individual osseous tunnels were made on the greater tuberosity around the insertion of the supraspinatus tendon. Each specimen was sequentially tested in 2 parts: a needle penetration test (part I) to measure the peak axial force and temperature change and a single load-to-failure test (part II) to measure the maximum load to failure as well as the mechanism of failure. A No. 2 FiberWire suture with a straight needle was used.

RESULTS

In part I, the mean peak axial force was lower in the study group compared with the control group for all osseous tunnels but was not statistically significant for individual tunnels. However, there was a significant decrease in peak axial force in the study group of 36% compared with the control group overall (P = .033). There was no significant change in temperature of the tunnel site with the use of electrocautery (mean: 0.2 ± 0.3°C, P = .435). In part II, 100% of the samples from each study group experienced bone tunnel failure. Forty percent of the trials in the study group found lower ultimate failure loads compared with the control group (reduction range: 7%-38%). There was no statistically significant difference in the ultimate failure load between either the loop tested or between the 2 study groups (loop 1: P = .352; loop 2: P = .270).

CONCLUSION

Suture passage using electrocautery does significantly decrease the peak force needed to pass a needle directly through the greater tuberosity. This technique does not appear to burn the bone or weaken the bone tunnels. This technique may be useful during open rotator cuff repair or shoulder arthroplasty, although clinicians should be cautious when using this technique as its utility depends on bone quality and cortical thickness, and in vivo results may differ.

Proximal Humerus Fracture/Dislocation: Look for the Greater Tuberosity

The shoulder is the commonest major joint involved in dislocations. These are often associated with fractures of the surgical neck and/or of the greater tuberosity of the proximal humerus. A good functional recovery is associated with a successful union of the tuberosity fragment, as this carries the insertion of the superior and posterior rotator cuff tendons. A 29-year-old male patient presented to our Emergency Department (ED) after a fall off his motorbike, resulting in a left shoulder fracture dislocation and an axillary nerve injury. His shoulder was reduced under sedation in the ED, with post-reduction radiographs demonstrating a seemingly satisfactory fracture position. Later on, a computerized tomography (CT) scan was arranged which actually confirmed significant displacement of his greater tuberosity, which was not picked up on initial post-reduction radiographs. As a result of identifying the displacement, surgical fixation with a locking plate and suture construct was undertaken. This case demonstrates the ease with which greater tuberosity fractures can mistakenly be presumed as reduced on post-reduction films, whilst in fact they can be significantly displaced. This risk is especially great when only one radiographic view is obtained. The sign of the 'disappearing tuberosity' on a plain radiograph should prompt the clinician to seek further imaging by way of CT, to uncover the true position of the greater tuberosity.

Effect of Quality of Repair on Clinical and Structural Outcomes of Rotator Cuff Repair

BACKGROUND

Anatomic repair of a torn rotator cuff tendon on the greater tuberosity (GT) is an important surgical goal in rotator cuff repair. However, few studies have investigated whether the efforts made to maximize coverage of the GT are associated with the clinical and structural outcomes after rotator cuff repair surgery.

PURPOSE

To investigate whether the quality of repair at the time of surgery is associated with clinical and structural outcomes after surgery and to identify factors influencing the quality of repair.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were retrospectively collected from 141 patients who underwent arthroscopic rotator cuff repair between 2008 and 2016. All repairs were classified according to the amount of postoperative GT coverage: A, complete coverage of the GT (n = 96); B, incomplete coverage, comprising more than half of GT (n = 27); C, incomplete coverage, comprising less than half of the GT (n = 16); and D, exposure of the glenohumeral joint (n = 2). All patients underwent magnetic resonance imaging 1 year after surgery. Clinical outcomes and structural integrity based on Sugaya classification were assessed 2 years and 1 year after surgery, respectively. Preoperative factors associated with the postoperative GT coverage (measured at the close of surgery) were identified using a multivariable proportional odds cumulative logit model.

RESULTS

The forward flexion strength in group A (10.3 ± 4.6 lb) was significantly greater than that in group C (6.5 ± 3.7 lb) (P = .003) 2 years after surgery. The postoperative Constant score in group A (76.6 ± 11.5) was greater than that in group C (66.7 ± 15.6) (P = .018). The number of cases that showed retearing of the repaired tendon was as follows: group A (5/96; 5.2%), group B (7/27; 25.9%), and group C (10/16; 62.5%). There was no significant difference in the changes of pain visual analog scale scores among groups 2 years after surgery (all P > .05). Also, there was no significant difference in the changes of range of motion in all directions among groups 2 years after surgery (all P > .05). Patients with preoperative GT coverage B included in the postoperative GT coverage groups through surgery were as follows: group A (23/45; 51.1%), group B (17/45; 37.8%), and group C (5/45; 11.1%). Preoperative GT coverage was the only independent factor that was associated with GT coverage in multivariable analysis.

CONCLUSION

Quality of repair, measured as the extent of postoperative GT coverage at the time of surgery, was associated with clinical and structural outcomes after rotator cuff repair surgery.

Menopause-related cortical loss of the humeral head region mainly occurred in the greater tuberosity

AIMS

Proximal humerus fractures are commonly observed in postmenopausal women. The goal of this study was to investigate menopause-related changes in cortical structure of the humeral head.

MATERIALS AND METHODS

Clinical computed tomography (CT) scans of 75 healthy women spanning a wide range of ages (20-72 years) were analyzed. For each subject, cortical bone mapping (CBM) was applied to create a color three-dimensional (3D) thickness map for the proximal humerus. Nine regions of interest (ROIs) were defined in three walls of the humeral head. Cortical parameters, including the cortical thickness (CTh), cortical mass surface density (CM), and the endocortical trabecular density (ECTD), were measured.

RESULTS

Compared to premenopausal women, postmenopausal women were characterized by a significantly lower CTh and CM value in the lateral part of the greater tuberosity. Similar changes were only found in ROI 4, but not in ROIs 5-6 in the lesser tuberosity. Linear regression analysis revealed that the CTh and CM value of ROIs 1, 3, and 4 were negatively associated with age. These results showed that menopause-related loss in CTh and CM was mainly in the greater tuberosity besides the proximal part of the lesser tuberosity. Trabecular bone variable measured as ECTD showed a notably lower value in ROIs 1-9 in postmenopausal vs. premenopausal group. Inverse linear associations for ECTD and age were found in ROIs 2, 3, 5, 6, 7, and 9, indicating no site-specific differences of endocortical trabecular bone loss between the greater and lesser tuberosity.

CONCLUSIONS

Menopause-related cortical loss of the humeral head mainly occurred in the lateral part of the greater tuberosity. The increased rate of humeral bone loss in the greater tuberosity may contribute materially to complex proximal humerus fractures.

Fracture-Dedicated Prosthesis Promotes the Healing Rate of Greater Tuberosity in Reverse Shoulder Arthroplasty: A Meta-Analysis

Introduction: Reverse shoulder arthroplasty (RSA) is becoming popular in the treatment of complex proximal humeral fractures (PHFs). Greater tuberosity healing may influence functional outcomes and range of motion (ROM) of shoulder after RSA. In addition, the design of prosthesis may impact the healing rate of greater tuberosity. The purpose of this study is to know: (1) does the healing of greater tuberosity affect the functional outcomes and ROM of shoulder? and (2) does the design of prosthesis affect the healing rate of greater tuberosity? Materials and Methods: PubMed, Ovid/Embase, and the Cochrane Library were searched for studies comparing the clinical outcomes between the healed groups and the non-healed groups after RSA. Results: For functional outcomes, the results showed that the healed group had better Constant scores (CSs) (p < 0.0001). For ROM, the healed group showed better flexion (p < 0.0001), abduction (p = 0.02), and external rotation (p < 0.00001) of shoulder. For the design of prosthesis, the mean healing rate of greater tuberosity (82.7%) in patients with fracture-dedicated prosthesis was higher than those (63.0%) in patients with standard prosthesis. Subgroup analyses showed that the CS (p = 0.12) and abduction (p = 0.96) of patients using fracture-dedicated prostheses were not different between the healed groups and the non-healed groups. Meta-regression showed that there was no significant relationship between the design of prosthesis and CS (p = 0.312), flexion (p = 0.422), or external rotation (p = 0.776). Conclusion: Our meta-analysis showed that the healed groups could obtain better functional outcomes and ROM than the non-healed groups. In addition, fracture-dedicated prostheses promoted the healing rate of greater tuberosity. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020157276, PROSPERO: CRD42020157276.

Displacement of the Greater Tuberosity in Humeral Head Fractures Does Not only Depend on Rotator Cuff Status

It is assumed that dorsocranial displacement of the greater tuberosity in humeral head fractures is caused by rotator cuff traction. The purpose of this study was to investigate the association between rotator cuff status and displacement characteristics of the greater tuberosity in four-part humeral head fractures. Computed tomography scans of 121 patients with Neer type 4 fractures were analyzed. Fatty infiltration of the supra- and infraspinatus muscles was classified according to Goutallier. Position determination of the greater tuberosity fragment was performed in both coronary and axial planes to assess the extent of dorsocranial displacement. Considering non-varus displaced fractures, the extent of the dorsocranial displacement was significantly higher in patients with mostly inconspicuous posterosuperior rotator cuff status compared to advanced fatty degenerated cuffs (cranial displacement: Goutallier 0–1: 6.4 mm ± 4.6 mm vs. Goutallier 2–4: 4.2 mm ± 3.5 mm, p = 0.020; dorsal displacement: Goutallier 0–1: 28.4° ± 32.3° vs. Goutallier 2–4: 13.1° ± 16.1°, p = 0.010). In varus displaced humeral head fractures, no correlation between the displacement of the greater tuberosity and the condition of the posterosuperior rotator cuff could be detected (p ≥ 0.05). The commonly accepted theory of greater tuberosity displacement in humeral head fractures by rotator cuff traction cannot be applied to all fracture types.

Bone resorption of the greater tuberosity after open reduction and internal fixation of complex proximal humeral fractures: fragment characteristics and intraoperative risk factors

HYPOTHESIS AND BACKGROUND

In complex proximal humeral fractures, bone resorption of the greater tuberosity is sometimes observed after open reduction and internal fixation (ORIF). However, this has not been well characterized, and risk factors for resorption are not completely understood. We aimed (1) to identify the risk factors associated with bone resorption of the greater tuberosity and (2) to quantify the geometric and bone density characteristics associated with bone resorption using 3-dimensional computed tomography models in complex proximal humeral fractures treated with ORIF.

METHODS

We identified a retrospective cohort of 136 patients who underwent ORIF of 3- or 4-part proximal humeral fractures; greater tuberosity resorption developed after ORIF in 30 of these patients. We collected demographic, fracture-related, and surgery-related characteristics and performed multivariable logistic regression analysis to identify factors independently associated with the development of greater tuberosity resorption. Furthermore, we identified 30 age- and sex-matched patients by use of propensity score matching to perform quantitative fragment-specific analysis using 3-dimensional computed tomography models. After the fragment of the greater tuberosity was identified, the number of fragments, the relative fragment volume to the humeral head, and the relative bone density to the coracoid process were calculated. Measurements were compared between matched case-control groups.

RESULTS

We found that an unreduced greater tuberosity (odds ratio [OR], 10.9; P < .001), inadequate medial support at the calcar (OR, 15.0; P < .001), and the use of an intramedullary fibular strut (OR, 4.5; P = .018) were independently associated with a higher risk of bone resorption. Quantitative fragment-specific analysis showed that greater tuberosities with a larger number of fragments (5 ± 2 vs. 3 ± 2, P = .021), smaller fragments (9.9% ± 3.8% vs. 18.6% ± 4.7%, P < .001), and fragments with a lower bone density (66.4% ± 14.3% vs. 88.0% ± 18.4%, P = .001) had higher rates of resorption.

DISCUSSION AND CONCLUSION

An unreduced greater tuberosity or inadequate medial support increases the risk of greater tuberosity resorption, as do a larger number of fracture fragments, smaller fragments, and lower bone density. Additionally, fibular strut grafting is an independent risk factor for tuberosity resorption. Further study is needed, but alternatives to strut grafting such as femoral head allograft may warrant serious consideration.

Fracture-Specific and Conventional Stem Designs in Reverse Shoulder Arthroplasty for Acute Proximal Humerus Fractures-A Retrospective, Observational Study

Tuberosity healing and stem design can be outcome-dependent parameters in hemiarthroplasty for proximal humerus fractures (PHF). The relevance of fracture-specific stem design in reverse shoulder arthroplasty (RSA) is still a matter of debate. This retrospective study evaluates tuberosity healing and function for fracture specific stems (A) compared to conventional stems (B) in RSA for complex PHF in 26 patients (w = 21, mean age 73.5 years). Clinically, range of motion (ROM), Constant-Murley-Score (CS), Subjective Shoulder Value (SSV), and external rotation lag signs (ERLS) were evaluated. Healing of greater tuberosity (GT) and lesser tuberosity (LT), scapular notching, and loosening were examined radiologically. There were no statistical significant differences with regards to CS (A: 73 ± 11; B: 77 ± 9 points), SSV (A: 78% ± 11%; B: 84% ± 11%), external rotation (A: 18° ± 20°; B: 24° ± 19°), or internal rotation (A: 5.7 ± 2.2; B: 6.7 ± 2.8 CS-points) (p > 0.05). Mean forward flexion was superior for group A (p = 0.036). Consolidation of GT (82%) and LT (73%) was similar in both groups. Anatomical healing was slightly higher in group B (p > 0.05). Scapular notching was found in 27% (A) and 55% (B) (p > 0.05). RSA for PHF provides good to excellent clinical results. The quantitative and qualitative union rate for both cohorts was similar, indicating that fracture stems with open metaphyseal designs to allow for bone ingrowth do not improve tuberosity healing. ERLS correlates with a worse function in CS and ROM in all planes.

The acromion-greater tuberosity impingement index: A new radiographic measurement and its association with rotator cuff pathology

PURPOSE

Several radiographic parameters describe humeral head coverage by the acromion. We describe a new radiographic measurement, the acromion-greater tuberosity impingement index (ATI), and its ability to predict rotator cuff pathology.

METHODS

The ATI was measured with magnetic resonance imaging (MRI) and X-ray analysis in 83 patients with rotator cuff pathology and 76 patients with acute rotator cuff tears. The lateral acromial angle (LAA), acromion type, the acromion index (AI) and the critical shoulder angle (CSA) were measured to assess their correlations with the ATI. Receiver operating characteristic (ROC) curves were used to predict degenerative rotator cuff pathology. The change in the ATI after acromion surgery was evaluated in both groups.

RESULTS

According to the ROC curves, the ATI is a good predictor of degenerative rotator cuff pathology on both X-ray (cut-off, 0.865) and MRI (cut-off, 0.965). Patients with degenerative rotator cuff pathology had a significantly higher average ATI compared to the trauma group (p = 0.001 for X-ray and MRI). The degenerative group had a significantly lower LAA (p = 0.001) and a higher ratio of type III acromion (p = 0.035) than the trauma group. The ATI on X-ray was negatively related to the LAA and positively related to the AI, the CSA and acromion type (each p < 0.05). The ATI on MRI was negatively related to the LAA and positively related to the AI and acromion type (each p <0.05). More patients in the degenerative group than the trauma group needed acromioplasty or acromion decompression (p < 0.05). The ATI on MRI was significantly lower after acromion surgery compared to before surgery in both groups (p < 0.05).

CONCLUSION

The ATI is a good predictor of degenerative supraspinatus tendon tears or subacromial impingement syndrome. The ATI on MRI is more accurate and can precisely guide acromion surgery.

SECEC Grammont Award 2017: the prejudicial effect of greater tuberosity osteotomy or excision in reverse shoulder arthroplasty for fracture sequelae

HYPOTHESIS

The aim was to evaluate risk factors for complications, revision, and mid- to long-term outcomes after reverse shoulder arthroplasty (RSA) implanted for proximal humeral fracture sequelae (PHFS).

METHODS

The radiographs of 98 patients (mean age, 68 years) who underwent RSA for the treatment of PHFS were reviewed at a minimum 5-year follow-up. PHFS were divided into 4 types according to the Boileau classification: type 1 (46 cases), type 2 (6 cases), type 3 (12 cases), and type 4 (34 cases). The tuberosities underwent osteotomy in 28 cases and excision in 12 (all type 3 or 4 PHFS). The mean follow-up period was 8.4 years (range, 5-14 years).

RESULTS

The functional results and rate of RSA survival without revision (85% vs. 100% at 10 years, P = .007) were significantly lower for types 3 and 4 vs. types 1 and 2. Overall, our findings showed that RSA for PHFS is not the panacea that surgeons once believed: At a mean follow-up of 8.5 years (range, 5-14 years), 59% of the patients in our series had fair or poor results. Patients who underwent tuberosity osteotomy or excision had lower functional results (adjusted Constant score, 69% vs. 88%; P < .001), more postoperative complications (32% vs. 9%, P = .003), and a higher revision rate (15% vs. 2%, P = .017). Patients who underwent tuberosity osteotomy or excision at the time of RSA were at risk of postoperative prosthetic instability and humeral stem loosening. The absence of the greater tuberosity at last radiographic follow-up was predictive of higher rates of complications and revisions, as well as a poorer final outcome. Previous fracture fixation was associated with a higher rate of complete tuberosity resorption (56% vs. 33%, P = .026) and with higher rates of postoperative complications (27% vs. 13%, P = .099) and reinterventions (17% vs. 2%, P = .018).

CONCLUSION

The functional results and rates of complications and revision depend on the type of fracture sequelae and tuberosity management. Patients with more severe (type 3 and 4) fracture sequelae who undergo tuberosity osteotomy or excision are at risk of having a poorer functional result and higher rates of complications and revision with lower survival. Previous fracture fixation is also a prejudicial factor.

Reverse shoulder arthroplasty for the treatment of acute complex proximal humeral fractures: Influence of greater tuberosity healing on the functional outcomes

PURPOSE

To investigate the influence of greater tuberosity healing on the functional outcomes of reverse shoulder arthroplasty (RSA) for the treatment of acute complex proximal humeral fractures (PHFs), and to investigate the influence of patient- and surgery-related factors in the healing of the greater tuberosity.

METHODS

Retrospective study including 41 consecutive PHFs treated using RSA with minimum 2-year follow-up. In all the cases, tuberosities were reattached with a standardized technique. All the patients were assessed at the last follow-up with constant score. Body mass index, surgery delay, comorbidities, polyethylene size, glenosphere size, overhanging of glenosphere, and scapular notch were recorded, and their influence in final constant score and in greater tuberosity healing was analyzed.

RESULTS

Mean final constant score was of 60.7 points (standard deviation (SD) = 9.9). Greater tuberosity healed in proper position in 68% of the cases. There were no significant differences in constant score between patients with (mean = 61; SD = 9.5) and without (mean = 61; SD = 11.3) the healing of greater tuberosity. All patients scored above 90° in forward elevation. Scapular notch was reported in 14.6% of the cases. Age significantly affected the constant score ( p = 0.008). Comorbidities significantly interfered with greater tuberosity healing ( p = 0.03). There was one reoperation after dislocation.

CONCLUSION

In spite of expecting good functional outcome with low complication rate after RSA for acute PHFs, the influence of greater tuberosity healing on shoulder function could not be demonstrated. The presence of comorbidities, but not age or gender, negatively influenced the healing of the greater tuberosity.

Greater tuberosity angle and critical shoulder angle according to the delamination patterns of rotator cuff tear

The purpose was to evaluate the relationship between GTA, CSA, and the delamination patterns of RCTs. This study included 315 patients with RCTs from 2014 to 2018, retrospectively. The subjects were divided into 5 groups: Group A, control group; Group B, non-delaminated tear; Group C, delaminated tear with equally retraction of articular and bursal layer; Group D, articular layer more retracted delaminated tear, and Group E, bursal layer more retracted delaminated tear. In conclusion, large GTA and CSA were associated with rotator cuff tears. However, there was no difference of GTA and CSA according to the delamination patterns.

Surgical Management of Comminuted, Displaced Greater Tuberosity Fractures: A New Technique of Subacromial Spacer on Top of Double-Row Suture Anchor Fixation

Arthroscopic treatment of greater tuberosity (GT) fractures has been previously described. Arthroscopy allows identifying and addressing coexisting injuries, such as rotator cuff tears, labrum, or superior labrum anterior and posterior lesions, which are often present. Fracture comminution precludes the use of rigid fracture fixation with screws and arthroscopic rotator cuff repair is performed instead. Recent articles have depicted the role of the balloon-shaped subacromial spacer in massive and irreparable rotator cuff tears. The purpose of this technical report is to outline another use of the spacer in patients with a GT fracture. The concept is to leverage the advantage of the compression effect of the subacromial spacer to prevent displacement of the GT fracture and allow early active shoulder rehabilitation, especially in comminuted or eggshell fractures when rigid fixation is not feasible.

The greater tuberosity angle: a new predictor for rotator cuff tear

BACKGROUND

The implication of scapular morphology in rotator cuff tears has been extensively studied. However, the role of the greater tuberosity (GT) should be of equal importance. The aim of this study was to propose a new radiographic marker, the GT angle (GTA), which measures the position of the GT in relation to the center of rotation of the humeral head. The hypothesis was that a higher angle value would be associated with a higher likelihood in detecting a rotator cuff tear.

METHODS

During 1 year, patients were prospectively recruited from a single institution specialized shoulder clinic in 2 different groups. The patient group consisted of individuals with a degenerative rotator cuff tear involving at least the supraspinatus. The control group consisted of individuals with no rotator cuff pathology. Individuals in both groups with congenital, post-traumatic, or degenerative alterations of the proximal humerus were excluded. The GTA was measured on an anteroposterior shoulder x-ray image with the arm in neutral rotation by 3 observers at 2 different times.

RESULTS

The study recruited 71 patients (33 patients, 38 controls). Mean GTA value was 72.5° (range, 67.6°-79.2°) in patients and 65.2° (range, 55.8°-70.5°) for controls (P <.001). A value above 70° resulted in 93-fold higher odds of detecting a rotator cuff tear (P <.001). Interobserver and intraobserver reliability were high.

CONCLUSIONS

GT morphology is implicated in rotator cuff tears. The GTA is a reliable radiographic marker, with more than 70° being highly predictive in detecting such lesions.

Subacromial corticosteroid injections transiently decrease suture anchor pullout strength: biomechanical studies in rats

BACKGROUND

Arthroscopic rotator cuff (RC) repair incorporates suture anchors to secure torn RC tendons to the greater tuberosity (GT) bone. RC repair strength depends on the anchor-bone interface and on the quality of the GT. We evaluated the effect of single and multiple corticosteroid injections on the pullout strength of suture anchors.

METHODS

Fifty rats were divided into those receiving saline solution injection (control group), a single methylprednisolone acetate (MTA) injection (MTA1 group), or 3 once-weekly MTA injections (MTA3 group). Rats were killed humanely at 1 or 4 weeks after the last injection. A mini-suture anchor was inserted into the humeral head through the GT. Specimens were tested biomechanically.

RESULTS

At 1 week after the last injection, the mean maximal pullout strength was significantly reduced in the MTA1 group (63.5%) and MTA3 group (56%) compared with the control group (P < .05 for both). Mean stiffness decreased significantly in both treatment groups compared with controls (P < .05). At 4 weeks after the last injection, there was a significant increase in the mean maximal pullout strength after single and triple MTA injections compared with values recorded at the 1-week time point (P < .05). At 4 weeks, the mean maximal pullout strength after a single MTA injection was 92.8% of the pullout strength measured in the control group.

CONCLUSIONS

We showed a significant detrimental effect of corticosteroid exposure on the pullout strength of a suture anchor at 1 week. However, this effect was transient and resolved within a relatively short period. These findings indicate that a waiting period is required between subacromial corticosteroid injection and RC repair surgery that involves the use of suture anchors.

Detrimental Effect of Repeated and Single Subacromial Corticosteroid Injections on the Intact and Injured Rotator Cuff: A Biomechanical and Imaging Study in Rats

BACKGROUND

The effect of corticosteroids on tendons is poorly understood, and current data are insufficient and conflicting.

PURPOSE

To evaluate the effects of corticosteroid injections on intact and injured rotator cuffs (RCs) through biomechanical and radiographic analyses in a rat model.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 70 rats were assigned to 7 groups. Uninjured rats (no tear) received either a single saline injection, a single methylprednisolone acetate (MTA) injection, or triple MTA injections. Injured rats (unilateral supraspinatus injury) received either a single saline injection, triple saline injections, a single MTA injection, or triple MTA injections (injections were subacromial; repeat injections were administered weekly). Rats were sacrificed 1 week after final injection. Shoulders were harvested and grossly inspected, and the supraspinatus tendon was evaluated biomechanically. Bone density at the tendon insertion site on the greater tuberosity was assessed by micro-computed tomography.

RESULTS

Intact RCs exposed to triple MTA injections had significantly decreased maximal load and stiffness compared with the control group (14.43 vs 21.25 N and 8.21 vs 16.6 N/mm, respectively; P < .05). Injured RCs exposed to steroid treatment had significantly lower maximal load (single saline: 10.91 N, single steroid: 8.43 N [P < .05]; triple control: 15.77 N, triple steroid: 11.65 N [P < .05]) compared with the control at 3 weeks. Greater tuberosity volume density and connectivity density were significantly lower in undamaged rats after triple MTA injection (P < .05).

CONCLUSION

The study results clearly showed that repeated doses of corticosteroids significantly weaken rat RC and negatively affect bone quality in addition to possibly causing deterioration of the osteotendinous junction. However, data retrieved from animals must be scrupulously analyzed before extrapolation to humans. As such, the potential benefits and harms of subacromial corticosteroid treatment must be considered before administration.

CLINICAL RELEVANCE

The potential benefit and detrimental effects of corticosteroid injection should be thoroughly considered before it is administered subacromially in patients with RC injuries.

Measurement of volumetric bone mineral density in proximal humerus using quantitative computed tomography in patients with unilateral rotator cuff tear

BACKGROUND

The first purpose of this study was to reveal the clinically important region-specific volumetric bone mineral density (vBMD) of the proximal humerus in patients with unilateral rotator cuff tear (RCT), and the second was to evaluate the relationship between vBMD of the proximal humerus and BMD of the hip and lumbar spine measured using conventional dual-energy X-ray absorptiometry. Finally, we assessed whether any clinical factor could predict local osteoporosis of the proximal humerus.

METHODS

The study enrolled 65 patients who underwent arthroscopic repair of a unilateral RCT between April 2010 and July 2011 and had computed tomography scans of bilateral proximal humeri. Considering the suture bridge technique for RCT repair to be the leading treatment, region-specific BMD was measured in 7 volumetric blocks in the proximal humerus. Image and quantification processing was used to calculate the vBMD of each block.

RESULTS

The vBMD values in all 7 blocks of the symptomatic shoulder were significantly lower than those of the asymptomatic contralateral shoulder (P < .05). Regardless of RCT, the greater tuberosity showed significant location-dependence in vBMD value; that is, the vBMD value was the highest in the posterolateral portion and the lowest in the medial portions. No significant correlation was found between vBMD of the greater tuberosity and clinical factors except female gender.

CONCLUSION

The present study demonstrated the regional and bilateral differences in vBMD within the greater tuberosity in patients with unilateral RCT. Aside from female gender, no other clinical factors presented as risk factors for a higher possibility of osteoporosis.

Minimally displaced fractures of the greater tuberosity: outcome of non-operative treatment

BACKGROUND

Minimally displaced (<3 mm) and non-displaced fractures of the proximal humerus are a common source of disability; nevertheless, there is no agreement on the recommended rehabilitation program in these patients. The purpose of this study was to evaluate the outcome of this group of patients and describe the rehabilitation protocol we have used for the treatment of this injury.

METHODS

We retrospectively analyzed the records of patients diagnosed with minimally displaced (<3 mm) fractures of the greater tuberosity who were admitted to our institute between June 2007 and May 2008. Patients were treated with a three-phase protocol. In the first phase, patients were immobilized in a sling for 3 weeks. In the second phase, pendular and active assisted exercises were begun 3 to 6 weeks after the injury. In the third phase, active exercises were commenced starting 6 weeks after injury.

RESULTS

Sixty-nine patients matched our inclusion and exclusion criteria. At an average follow-up of 31 months (range, 26-41 months), the average Constant score improved from 40 points (range, 33-58 points) to 95 points (range, 75-100 points). Average satisfaction score improved from 4.2 of 10 (range, 2-6) to 9.5 of 10 (range, 7-10). The reported average duration of pain and decreased range of motion from the time of injury was 8.1 months (range, 1-24 months).

CONCLUSIONS

When the diagnosis of a minimally displaced fracture of the proximal humerus is made, the patient can be reassured that a favorable outcome is anticipated with a staged rehabilitation protocol. Nevertheless, clinicians and patients should be aware that full recovery from the injury may take an average of 8 months.

Bilateral Anterior Shoulder Dislocation with Symmetrical Greater Tuberosity Fracture following Seizure

INTRODUCTION

Majority of bilateral shoulder dislocations are posterior. Simultaneous bilateral anterior shoulder dislocations and bilateral anterior fracture-dislocations are rare and mostly of traumatic origin. We present a rare case of bilateral anterior shoulder dislocation with symmetrical greater tuberosity fracture following an episode of seizure with an unusual injury mechanism which was treated conservatively.

CASE REPORT

A 45 year old office worker presented to the Casualty of our hospital with bilateral anterior shoulder dislocations with greater tuberosity fractures following an episode of seizure. Both shoulders were reduced by Kocher manoeuvre using total intravenous anaesthesia (TIVA) & were strapped to the chest for 6 weeks. At the end of 1 year follow-up, there were no reasonable loss of strength or restriction of motion and the shoulders were defined as stable.

CONCLUSION

Although bilateral shoulder dislocations are mostly posterior, bilateral anterior dislocations may not be as rare as previously thought and are frequently missed by the orthopaedic residents in the casualty department. Further to the best of our knowledge, our case represents the first case of bilateral anterior shoulder dislocation with symmetrical greater tuberosity fracture with an unusual mechanism of injury following an episode of seizure in a young male patient that was successfully managed by conservative means.

Prediction of the rotational state of the humerus by comparing the contour of the contralateral bicipital groove: Method for intraoperative evaluation

BACKGROUND

Accurate reduction of rotational displacement for transverse or comminute fracture of humeral shaft fracture is difficult during operation. The purpose of this study was to evaluate the reliability of the bicipital groove as a point of reference for the prediction of the rotational state of the humerus on two dimensional images of C-arm image intensifier during operation for humeral shaft fractures.

MATERIALS AND METHODS

One hundred subjects, 62 male, 38 female, aged 22-53 years were recruited contralateral bicipital groove on the 45 degrees externally rotational standard anterior-posterior view recorded before surgery. Three observers, watched only contour of bicipital groove in monitor of C-arm image intensification with naked eye without looking at the subject and predicted rotational state of the humerus by comparing the contour of the opposite side of bicipital groove. The angle of discrepancy from real rotational position was then assessed.

RESULTS

The mean (SD), angular discrepancy between the neutral point and the predicted angle was 3.4°(±2.7°). A value within 5° was present in 72% of cases. All observations were within 15°. There was no interobserver variation (P = 0.47). The intraclass correlation coefficient (ICC) was 0.847.

CONCLUSION

Contour of the bicipital groove on simple radiograph was a useful landmark. Comparing the contour of the bicipital groove in the 45 degrees externally rotational standard view bilaterally, was an effective method for reduction of rotational displacement of the humerus.