Arthroscopic-assisted plate fixation for displaced large-sized comminuted greater tuberosity fractures of proximal humerus: a novel surgical technique

Management of greater tuberosity fracture dislocations of the shoulder

Background

Despite extensive literature dedicated to determining the optimal treatment of isolated greater tuberosity (GT) fractures, there have been few studies to guide the management of GT fracture dislocations. The purpose of this review was to highlight the relevant literature pertaining to all aspects of GT fracture dislocation evaluation and treatment.

Methods

A narrative review of the literature was performed.

Results

During glenohumeral reduction, an iatrogenic humeral neck fracture may occur due to the presence of an occult neck fracture or forceful reduction attempts with inadequate muscle relaxation. Minimally displaced GT fragments after shoulder reduction can be successfully treated nonoperatively, but close follow-up is needed to monitor for secondary displacement of the fracture. Surgery is indicated for fractures with >5 mm displacement to minimize the risk of subacromial impingement and altered rotator cuff biomechanics. Multiple surgical techniques have been described and include both open and arthroscopic approaches. Strategies for repair include the use of transosseous sutures, suture anchors, tension bands, screws, and plates. Good-to-excellent radiographic and clinical outcomes can be achieved with appropriate treatment.

Conclusions

GT fracture dislocations of the proximal humerus represent a separate entity from their isolated fracture counterparts in their evaluation and treatment. The decision to employ a certain strategy should depend on fracture morphology and comminution, bone quality, and displacement.

Comparison between arthroscopic suture anchor fixation and open plate fixation in the greater tuberosity fracture of the proximal humerus

INTRODUCTION

The purpose of this study is to compare the clinical and radiological outcomes of patients undergoing open reduction and internal fixation (OR/IF) using a plate or patients undergoing an arthroscopic suture anchor fixation for the greater tuberosity (GT) fracture of the proximal humerus. The purpose of this study is to compare the clinical and radiological outcomes of patients undergoing OR/IF or an arthroscopic suture anchor fixation for the GT fracture.

MATERIALS AND METHODS

Between January, 2010 and December, 2020, 122 patients with GT fracture underwent operative fixation. Either OR/IF using proximal humeral locking plate (50 patients) or arthroscopic suture anchor (72 patients) fixation was performed. Fourteen patients were lost to follow-up and finally, 108 patients were enrolled in this study. We divided these patients into two groups: (1) OR/IF group (Group I: 44 patients) and arthroscopic anchor fixation group (Group II: 64 patients). The primary outcome was subjective shoulder function (shoulder functional scale). Secondary outcomes were range of motion, and complications including GT fixation failure, fracture migration, or neurologic complication. Also, age, sex, BMI, operation time, shoulder dislocation, fracture comminution, AP (anteroposterior), SI (superoinferior) size and displacement were evaluated and compared between two groups.

RESULTS

Both groups showed satisfactory clinical and radiological outcomes at mid-term follow-up. Between 2 groups, there were no significant differences in age, sex, BMI, presence of shoulder dislocation or comminution. Group II showed higher clinical scores except VAS score (p < 0.05) and longer surgical times (95.3 vs. 61.5 min). Largest fracture displacement (Group I vs. II: SI displacement: 40 vs. 13 mm, and AP displacement: 49 vs. 11 mm) and higher complication rate (p = 0.049) was found in Group I.

CONCLUSIONS

Both arthroscopic anchor fixation and open plate fixation methods showed satisfactory outcomes at mid-term follow-up. Among them, OR/IF is preferred for larger fracture displacement (> 5 mm) and shorter operation time However, arthroscopic anchor fixation group showed better clinical outcomes and less complications than the OR/IF group.

LEVEL OF EVIDENCE

Level 4, Case series with subgroup analysis.

Numerical and Experimental Investigations of Humeral Greater Tuberosity Fractures with Plate Fixation under Different Shoulder Rehabilitation Activities

The incidence of humerus greater tuberosity (GT) fractures is about 20% in patients with proximal humerus fractures. This study aimed to investigate the biomechanical performances of the humerus GT fracture stabilized by a locking plate with rotator cuff function for shoulder rehabilitation activities. A three-dimensional finite element model of the GT-fracture-treated humerus with a single traction force condition was analyzed for abduction, flexion, and horizontal flexion activities and validated by the biomechanical tests. The results showed that the stiffness calculated by the numerical models was closely related to that obtained by the mechanical tests with a correlation coefficient of 0.88. Under realistic rotator cuff muscle loading, the shoulder joint had a larger displacement at the fracture site (1.163 mm), as well as higher bone stress (60.6 MPa), higher plate stress (29.1 MPa), and higher mean screw stress (37.3 MPa) in horizontal flexion rehabilitation activity when compared to that abduction and flexion activities. The horizontal flexion may not be suggested in the early stage of shoulder joint rehabilitation activities. Numerical simulation techniques and experimental designs mimicked clinical treatment plans. These methodologies could be used to evaluate new implant designs and fixation strategies for the shoulder joint.

Biomechanical comparisons of hook plate and screw fixations in split-type greater tuberosity fractures of the humerus

BACKGROUND

Screws and plate are commonly utilized for the fixation of split-type humeral greater tuberosity (GT) fractures. However, the mechanical properties of these 2 types of fixation methods have not been compared directly. The aim of the present study was to evaluate the classic 2 screws fixation with hook locking plate from a mechanical perspective.

METHODS

Sixteen synthetic humerii (Sawbones Pacific Research Laboratories, Vashon, WA, USA) were divided into 2 groups. An osteotomy was performed to simulate a split-type GT fracture. Group A (n = 8) was fixed with 2 standard parallel screws. Group B (n = 8) was fixed with a hook plate. Each specimen was tested with traction force at 45° shoulder abduction. Following the 20-N preload, a 500-cycle loading test was applied with a force ranging from 20 to 200 N (valley/peak), and the interfragmental displacement was measured periodically at intervals of 100 cycles. Finally, all the specimens were pulled with destructive force at a rate of 5 mm/min until catastrophic failure.

RESULTS

The hook plate exhibited greater construct stiffness than the screw fixation (63.2 ± 6.1 N/mm vs. 40.9 ± 3.4 N/mm, P < .001). All of the specimens completed the entire cyclic loading test without catastrophic failure, and the fragment displacement after 500 cycles was 0.4 ± 0.2 mm for the hook plate and 2.1 ± 0.3 mm for screw fixation, which was statistically lower in the plate group (P < .001). In terms of failure load, the hook plate group exhibited a significantly greater value than the screw group (770.6 ± 94.6 vs. 427.5 ± 45.1 N/mm, P < .001). The failure modes of both fixation methods were distinct.

CONCLUSION

In humeral GT fracture fixation, hook plate fixation appears to offer greater construct stiffness and failure load while maintaining fragment stability to resist a physiological traction force. The current study provides support from a mechanical perspective for the clinical application of the hook plate.

A new biomechanical classification system for split fractures of the humeral greater tuberosity: guidelines for surgical treatment

Background

Split fractures of the humeral greater tuberosity (HGT) are common injuries. Although there are numerous surgical treatments for these fractures, no classification system combining clinical and biomechanical characteristics has been presented to guide the choice of fixation method.

Methods

We created a standardised fracture of the HGT in 24 formalin-fixed cadavers. Six were left as single-fragment fractures (Group A), six were further prepared to create single-fragment with medium size full-thickness rotator cuff tear (FT-RCT) fractures (Group B), six were cut to create multi-fragment fractures (Group C), and six were cut to create multi-fragment with FT-RCT fractures (Group D). Each specimen was fixed with a shortened proximal humeral internal locking system (PHILOS) plate. The fixed fractures were subjected to load and load-to-failure tests and the differences between groups analysed.

Results

The mean load-to-failure values were significantly different between groups (Group A, 446.83 ± 38.98 N; Group B, 384.17 ± 36.15 N; Group C, 317.17 ± 23.32 N and Group D, 266.83 ± 37.65 N, P < 0.05). The load-to-failure values for fractures with a greater tuberosity displacement of 10 mm were significantly different between each group (Group A, 194.00 ± 29.23 N; Group B, 157.00 ± 29.97 N; Group C, 109.00 ± 17.64 N and Group D, 79.67.83 ± 15.50 N; P < 0.05). These findings indicate that fractures with a displacement of 10 mm have different characteristics and should be considered separately from other HGT fractures when deciding surgical treatment.

Conclusions

Biomechanical classification of split fractures of the HGT is a reliable method of categorising these fractures in order to decide surgical treatment. Our findings and proposed system will be a useful to guide the choice of surgical technique for the treatment of fractures of the HGT.

Traumatic Inferior Glenohumeral Dislocation Associated With Rotator Cuff Avulsion Fracture: Arthroscopic-Assisted Fixation: A Technical Note

Traumatic inferior glenohumeral dislocation with rotator cuff avulsion fracture rarely occurs and may cause chronic pain and diminished shoulder function. Several treatment options are available for this injury, such as open reduction internal fixation and arthroscopic-assisted reduction internal fixation. This technique describes a step-by-step technique to manage traumatic inferior glenohumeral dislocation with rotator cuff avulsion fracture using the simultaneous closed reduction procedure for traumatic inferior glenohumeral dislocation and the arthroscopic procedure with suture bridge technique for the treatment of rotator cuff avulsion fracture.

Surgical fixation of isolated greater tuberosity fractures of the humerus- systematic review and meta-analysis

OBJECTIVES

A systematic review was undertaken based on PRISMA guidelines to study the results of surgical treatment of Greater Tuberosity fractures of the Humerus by different techniques (Open, Percutaneous or Arthroscopic) and using different fixation devices (Sutures, Screws and Plates).

DATA SOURCES

Literature searches were performed for studies in English on four online databases (MEDLINE®, Embase®, Ovid® Emcare and CINAHL®) using a pre-planned search strategy.

STUDY SELECTION

Studies were screened against pre-decided inclusion and exclusion criteria. 24 articles were eligible for inclusion involving 562 patients in all.

DATA EXTRACTION

A template was used for collection of relevant data regarding the study design, demographics, fracture characteristics, surgical techniques and implants used, outcomes, complications and re-operations. Methodological quality was assessed using a modified Coleman Methodology Score.

DATA SYNTHESIS

Pooled analysis was conducted for (1) complications/reoperations of different devices; and (2) reported results using standard outcome measures of various techniques. Results were pooled using inverse variance method. When pooling proportions, we used arcsine transformation to account for zero events.

CONCLUSION

Use of screws was associated with higher rates of total complications (23.7%) as well as reoperations (13.2%), compared to sutures (14.2%; 2.6%) and plates (10.6%; 4.1%). In a subgroup analysis, use of low-profile plates (LPPs) was associated with the lowest rates of total complications (4.97%). The superiority of any surgical technique could not be established using the pooled Constant or ASES scores because there was lack of uniformity in the reporting of outcome measures. Our analysis of complications of the various fixation devices dissuades the use of screws and favours the use of low-profile plates. There is a need for prospective studies comparing arthroscopic suture fixation with open low-profile plate fixation of GT fractures.

Open Reduction and Stable Internal Fixation Using a 3.5-mm Locking Hook Plate for Isolated Fractures of the Greater Tuberosity of the Humerus: A 2-Year Follow-up Study Using an Innovative Fixation Method

Backgroud

The best treatment for isolated greater tuberosity (GT) fractures is still controversial. Although previous studies have suggested surgical options, they are either unable to provide firm fixation or present with a variety of complications.

Methods

We retrospectively studied the records of patients with isolated GT fractures who underwent open reduction and internal fixation using a 3.5-mm locking hook plate between January 2016 and January 2018. The surgical indication was an at least 5-mm displacement of the GT as observed in either simple radiography or three-dimensional computed tomography. Clinical outcomes were assessed using the following five parameters shortly before implant removal and at the final follow-up: visual analog scale (VAS) pain score, American Shoulder and Elbow Surgeons (ASES) score, Shoulder Rating Scale of the University of California, Los Angeles (UCLA), Constant-Murley score, and range of motion.

Results

Twenty-one patients with a mean age of 64 years were included. Bone union was achieved within 12–20 weeks of the first surgery in all patients. Implant removal was performed between 13 and 22 weeks after surgery. At the final follow-up, the mean VAS pain score, forward flexion, abduction, external rotation, internal rotation, ASES score, UCLA score, and Constant-Murley score were significantly better when compared to outcomes shortly before implant removal (p < 0.001, p < 0.001, p < 0.001, p = 0.008, p = 0.003, p < 0.001, p < 0.001, and p < 0.001, respectively).

Conclusions

The 3.5-mm locking hook plate provided sufficient stability and led to satisfactory clinical and radiological outcomes for isolated GT fractures. However, the hook plate may irritate the rotator cuff, and postoperative stiffness may be inevitable. Therefore, second surgery for implant removal is necessary after bone union is achieved.

A new low-profile anatomic locking plate for fixation of comminuted, displaced greater tuberosity fractures of the proximal humerus

BACKGROUND

Although various implants exist for the fixation of isolated greater tuberosity fractures, few implants are specifically designed for such fractures. The purpose of this study was to investigate the clinical and radiologic outcomes of open reduction-internal fixation with a low-profile anatomic locking plate for comminuted greater tuberosity fractures of the proximal humerus.

METHODS

From November 2012 to February 2018, 24 patients with displaced and comminuted isolated greater tuberosity fractures were treated with the new low-profile anatomic locking plate. To determine clinical outcomes, we evaluated active range of motion; the visual analog scale pain score; the Constant-Murley score; the Disabilities of the Arm, Shoulder and Hand score; radiographs; and complications.

RESULTS

In all cases, a mean follow-up period of 29.3 months (range, 18-48 months) was completed. All patients achieved bone union with a mean healing time of 11.3 weeks (range, 8-16 weeks). The mean Constant-Murley score was 91.1 points (range, 69-100 points), with a rate of good to excellent results of 95.8%. The average Disabilities of the Arm, Shoulder and Hand score was 9.9 points (range, 2-25 points), and the mean visual analog scale pain score was 1.1 points (range, 0-4 points). Mean active forward flexion, abduction, external rotation, and internal rotation (level) were 157°, 152°, and 40°, and T11, respectively. Postoperatively, 1 patient had persistent shoulder stiffness, and 1 patient had recurrence of shoulder dislocation because of a falling injury during badminton. No serious complications such as subacromial impingement, malunion, nonunion, loss of reduction, or implant failure occurred.

CONCLUSIONS

The new low-profile anatomic locking plate was useful for the treatment of comminuted isolated greater tuberosity fractures as it provided reliable stability and satisfactory radiographic and functional results. The described technique is a simple and effective method and provides a new reliable option for the treatment of isolated greater tuberosity fractures.

Arthroscopic fixation of humeral greater tuberosity fracture using a W-shaped suture

Background

Patients with greater tuberosity fractures of the humerus often require surgery. Therefore, there is a need to find a minimally invasive and effective surgical procedure with great patient outcomes.

Aim

To evaluate the clinical outcomes of the W-shaped suture technique under shoulder arthroscopy in the treatment of greater tuberosity fractures of the humerus.

Methods

In this retrospective study, a total of 17 patients were included. The fractures were closed, and there was no neurovascular injury. These patients underwent arthroscopically assisted reduction and internal fixation of the greater tuberosity fractures. Fixation was performed using sighting nails combined with a W-shaped suture. The imaging data of the patients were collected, and the ASES score, Constant-Murley score, and VAS score were used to evaluate the patient’s outcome. At the last follow-up (at least 1 year), the range of motion in the affected shoulder was compared with that of the contralateral side.

Results

The operation was successful in all the patients. The average follow-up time was 13 months. There were no reported complications such as fracture displacement, nonunion, and internal fixation failure during the follow-up period. Post-operative X-ray examinations revealed good function recovery, with a healing time of between 10 and 12 weeks, and an average healing time of 11.5 weeks. Following the operation, patients reported reduced shoulder joint pain that no longer influenced their activity or caused discomfort in their daily life. The patient’s VAS score ranged from 0 to 3, with an average of 0.52 ± 0.73, while at the last follow-up, the Constant-Murley score ranged from 83 to 97, with an average of 92.33 ± 7.55. The ASES score ranged from 81 to 98, with an average of 93.15 ± 6.93. At the last follow-up, there was no significant difference in the overall range of motion with the unaffected limb.

Conclusion

This study demonstrates that the W-shaped suture can be used to effectively fix the fractures of the greater tuberosity of the humerus, by increasing the fixed area to promote healing.

Plate Fixation versus Arthroscopic-Assisted Plate Fixation for Isolated Medium-Sized Fractures of the Greater Tuberosity: A Retrospective Study

Objectives

To compare the clinical outcomes of plate fixation and arthroscopic‐assisted plate fixation in patients with displaced isolated medium‐sized fractures of the greater tuberosity.

Methods

From July 2013 to October 2017, patients with displaced isolated medium‐sized fractures of the greater tuberosity who underwent arthroscopic‐assisted plate fixation (ASPF group) or open reduction and internal plate fixation (ORIF group) were retrospectively reviewed and analyzed. There were 19 patients in the ASPF group and 27 patients in the ORIF group, with comparable demographic characteristics. The average age of patients was 49.4 ± 12.1 years in the ASPF group and 46.9 ± 11.4 years in the ORIF group. The shoulder function reflected by the Constant–Murley (CS) scores, the American Shoulder and Elbow Surgeons (ASES) scores, and the range of motion (ROM) in the both groups at the last follow‐up were analyzed in the study. Surgery time, postoperative pain, and postoperative complications were also reviewed.

Results

A total of 46 eligible patients were included in this study. The mean follow‐up was similar for the ASPF (19.4 ± 3.7 months) and the ORIF (18.2 ± 3.2 months) groups (P = 0.372). All patients had achieved primary incision healing in both groups at the last follow‐up. The surgery time was 96.8 ± 11.7 min and 64.2 ± 8.3 min in the ASPF group and the ORIF group, respectively (P < 0.01). All the CS scores (P = 0.278), ASES scores (P = 0.426), and ROM were slightly better in the ASPF group than in the ORIF group, but they did not attain significant differences. In addition, there was no significant difference in the postoperative complication rate between the ASPF group (10.5%) and the ORIF group (18.5%) (P = 0.522). In the ASPF group, there was only one patient with postoperative shoulder stiffness and one case of fracture malunion. In the ORIF group, there were two cases of postoperative shoulder stiffness, two cases of fracture malunoin, and one case of subacromial impingement. Other major postoperative complications, such as fracture nonunion, pullout of the suture anchor, and screw penetration, were not observed in either group.

Conclusion

Arthroscopic‐assisted plate fixation is effective and may be an alternative in the treatment of displaced isolated medium‐sized fractures of the greater tuberosity.

Outcomes of surgical fixation of greater tuberosity fractures: A systematic review

BACKGROUND

Isolated greater tuberosity fractures account for up to a fifth of all proximal humeral fractures. There have been several retrospective cohort studies and case series reporting outcomes after treatment of this pathology. This study aims to report on the clinical outcomes of surgically treated isolated greater tuberosity fractures, as well as diagnostic workup and complications associated with fracture fixation.

METHODS

A systematic review was performed under PRISMA guidelines to identify studies that reported the results or clinical outcomes of isolated greater tuberosity fracture. The searches were performed using MEDLINE through PubMed, the Elsevier Embase database, and the Cochrane Database of Systematic Reviews.

RESULTS

Sixteen studies met inclusion criteria comprising 345 patients and 345 shoulders. The mean age was 52.9 years and mean follow-up was 3.4 months. The mean postoperative American Shoulder and Elbow Surgeon Score, the most frequently utilized patient reported outcome measure across studies, was 90.1% of ideal maximum. All studies used standard shoulder radiographs in their initial workup and most commonly referred to a minimum of 5mm displacement as an indication for surgery. Fifty five percent of patients were treated using open fixation and 35.9 with arthroscopic fixation. Ninety three percent of patients were able to return to work. A total of fifty-two (15.1%) complications were reported in the included studies.

CONCLUSIONS

The current literature describes overall satisfactory functional outcomes and minimal occupational morbidity following either open or arthroscopic fixation of isolated greater tuberosity fractures despite a notable rate of complications.

LEVEL OF EVIDENCE

IV, systematic review.

Arthroscopic Reduction and Suture Bridge Fixation of a Large Displaced Greater Tuberosity Fracture of the Humerus

Arthroscopic fixation of a greater tuberosity (GT) avulsion fracture by suture bridge repair has been described in several articles. However, all of them have used arthroscopic fixation of a small sized GT fracture fragment or have not used purely arthroscopic techniques. In this Technical Note, the authors describe another technique for large displaced GT fracture fixation by arthroscopy only, without any metal fixation. Standard anterior, posterior, lateral, and posterolateral viewing portals are established with an accessory portal for suture anchor insertion. During intra-articular examination, an anteroinferior capsulolabral tear, upper one-third subscapularis tendon tear, and posterosuperior displaced bony fragment are detected. A subscapularis tendon was repaired by a single-row technique. After repair, medial row anchors are inserted into the bare area of infraspinatus tendon and the posterior edge of supraspinatus tendon. A 1-PDS suture is used to pass strands of fiberwire. As with the remplissage procedure, the fiberwire was passed with an 18-gauge needle. Following the acromioplasty, the medial row tightening was done by reducing the fracture fragment. After that, the lateral row anchor was inserted into the bicipital groove, completing the suture bridge technique. This technique can effectively treat other pathologies, has less radiation hazard, and results in fewer soft tissue injuries.

Biomechanical Analysis of the Fixation Strength of a Novel Plate for Greater Tuberosity Fractures

Background

The incidence of isolated greater tuberosity fractures has been estimated to be 20% of all proximal humeral fractures. It is generally accepted that displaced (>5 mm) fractures should be treated surgically but the optimal surgical fixation of greater tuberosity fractures remains unclear.

Objective

The goal of this study was to simulate the environment of application of a new plate system (Kaisidis plate, Fa Königsee) for fractures of greater tuberosity, and to demonstrate the stability of the plate.

Methods

A Finite Element Method (FEM) simulation analysis was performed on a Kaisidis plate fixed with nine screws, in a greater tuberosity fracture model. Solid Works 2015 simulation software was used for the analysis. The Kaisidis plate is a bone plate intended for greater tuberosity fractures. It is a low profile plate with nine holes for 2,4 mm diameter locking screws, eight suture holes and additional K-wire holes for temporary fixation of the fragment.The supraspinatus tendon has the greatest effect on the fracture zone, and as such, was the primary focus for this study. For this study, we performed only linear calculations.

Results

The calculations were performed in a way so that the total applied force resulted in a maximum stress of 816 N/mm². The findings indicated that the most critical points of the Kaisidis system are the screws that are connected to the bone. The maximal force generated by the supraspinatus tendon was 784 N, which is higher than the minimal acceptable force.The results of the FEM analysis showed that the maximal supraspinatus force was 11.6% higher than the minimal acceptable force. As such, the load would exceed twice the amount of maximal force required to tear the supraspinatus tendon, before the screw or the plate would show first signs of plastic deformation.

Conclusion

Based on the results of this analysis and the fulfilment of our acceptance criterion, the FEM model indicated that the strength of the Kaisidis plate exceeded that of the proposed maximum loads under non-cycli loading conditions.

Clinical outcomes of minimally invasive open reduction and internal fixation by screw and washer for displaced greater tuberosity fracture of the humerus

BACKGROUND

The purpose of this study was to investigate clinical and radiologic outcomes of open reduction and internal fixation with a screw and washer for a displaced greater tuberosity fracture of the proximal humerus through a small incision.

METHODS

We retrospectively reviewed 29 patients who underwent open reduction and internal fixation with a screw and washer for a greater tuberosity fracture of the proximal humerus. After surgery, the patients were immobilized in a brace for 4 weeks. To determine clinical outcomes, we evaluated a visual analog scale pain score; the Subjective Shoulder Value; the University of California, Los Angeles shoulder score; the American Shoulder and Elbow Surgeons score; and active range of motion.

RESULTS

All patients achieved bone union within 3 months after surgery. At the 2-year follow-up, the mean visual analog scale pain score was 1.1 ± 1.1; Subjective Shoulder Value, 93.4 ± 5.3; University of California, Los Angeles shoulder score, 31.2 ± 2.7; and American Shoulder and Elbow Surgeons score, 92.6 ± 6.7. Mean active forward flexion, external rotation, and internal rotation were 144° ± 16°, 33° ± 11°, and 13.3 ± 1.7, respectively. Postoperatively, 9 patients (31%) had stiffness and pain refractory to conservative treatment and underwent arthroscopic release.

CONCLUSION

Although minimal open reduction and screw and washer fixation resulted in bone union in all cases, the incidence of postoperative stiffness was relatively high in patients with displaced greater tuberosity fractures because of prolonged immobilization after surgery.

Single versus double row suture anchor fixation for greater tuberosity fractures - a biomechanical study

BACKGROUND

Fractures of the humeral greater tuberosity (GT) are a frequent injury progressively treated with arthroscopic suture anchor repair. Yet, no biomechanical study has been performed comparing fixation strength of arthroscopic single- (SR) vs. double row (DR) fixation.

METHODS

Standardized fractures of the greater tuberosity were created in 12 fresh frozen proximal humeri. After random assignation to the SR or DR group the fixed humeri were tested applying cyclic loading to the supraspinatus and infraspinatus tendon. Load to failure and fragment displacement were assessed by means of an electrodynamic material testing machine using an optical tracking system.

RESULTS

Load to failure values were higher in the DR group (649 N; ±176) than in the SR group (490 N; ±145) however without statistical significance (p = .12). In greater tuberosity displacement of 3-5 mm surgical treatment is recommended. The fixing constructs in this study did not reach displacement landmarks of 3 or 5 mm before construct failure as shown in previous studies. Thus the applied traction force (N) at 1 mm displacement was analyzed. In the SR group the load at 1 mm displacement was 277 N; ±46 compared to 260 N; ±62 in the DR group (p = .65).

CONCLUSION

The results suggest that both techniques are viable options for refixation of greater tuberosity fractures.

LEVEL OF EVIDENCE

Laboratory study.

Arthroscopic reduction and fixation for displaced greater tuberosity fractures using the modified suture-bridge technique

PURPOSE

The aim of this study was to evaluate the early clinical outcomes of arthroscopic treatment of avulsion or comminuted fractures of the greater tuberosity (GT) using a modified suture-bridge technique.

METHODS

Between February 2013 and November 2015, 14 patients with displaced or comminuted fractures of GT were arthroscopically treated using a modified suturebridge technique. Displacement of the GT fragments was > 3 mm in any plane. An analysis of follow-up results including the University of California, Los Angeles (UCLA) shoulder scale; the shoulder index of the American Shoulder and Elbow Surgeons (ASES); the simple shoulder test (SST); and shoulder range of motion (ROM), is presented.

RESULTS

Mean duration of follow up is 18.9 months (range, 6-30). Mean age of patients was 62.9 years (range, 49-74). Postoperatively, the outcomes were rated as excellent, good and fair in two, 11 and one patient, respectively based on the UCLA score. At the most recent follow-up, the average UCLA score increased to 32 points, the ASES score increased to 97.5 points, and the SST score increased to 11 points. Average forward flexion was 153.6°, average abduction was 158.6°, average external rotation in the neutral position was 38.6°, and internal rotation increased to the 12th thoracic vertebral level.

CONCLUSION

Early follow-up outcomes of the arthroscopic modified suture-bridge technique used for avulsion or comminuted GT fractures are promising. The technique can be used as one of the therapeutic modalities for GT fractures.