Biomechanical comparison of long head of biceps tenodesis with interference screw and biceps sling soft tissue techniques

Scapular spine base fracture with long outside-in superior or posterior screws with reverse shoulder arthroplasty

Background

The purpose of the present study was to determine how long superior screws alone or in combination with posterior placement of metaglene screws protruding and penetrating into the scapular spine in reverse total shoulder arthroplasty affect the strength of the scapular spine in a fresh cadaveric scapular model.

Methods

Seven fresh cadaver scapulas were allocated to the control group (short posterior and superior screws) and seven scapulars to the study group (spine base fixation with a four long screws, three with both long superior and long posterior screws).

Results

The failure load was lower in the spine fixation group (long screw, 869 N vs. short screw, 1,123 N); however, this difference did not reach statistical significance (p>0.05). All outside-in long superior or superior plus posterior screws failed due to scapular spine base fracture; failures in the short screw group were due to acromion fracture. An additional posterior outside-in screw failed to significantly decrease the failure load of the acromion spine.

Conclusions

The present study highlights the significance of preventing a cortical breach or an outside-in configuration when a superior or posterior screw is inserted into the scapular spine base.

Humerus Fractures After Open Subpectoral Biceps Tenodesis: Three Cases with 2-year Functional Outcome Data and Review of the Literature

CASE

The authors present 3 cases of humerus fracture after biceps tenodesis performed by 3 different surgeons with radiographs and outcome scores with a minimum of 30 months follow-up. Fractures occurred between 7 days and 4 months postoperatively and include 2 fractures where tenodesis had been performed with interference screw fixation and one fracture where tenodesis had been performed with a bicortical endobutton technique.

CONCLUSIONS

These case reports highlight the risk of this complication in biceps tenodesis with bony fixation. The authors review the previously reported cases and relevant biomechanical studies that elucidate risk factors for humerus fracture and discuss alternative means to treat biceps tendon pathology.

A Systematic Review and Meta-analysis of Biceps Tenodesis Fixation Strengths: Fixation Type and Location Are Biomechanically Equivalent

PURPOSE

The purpose of this meta-analysis and systematic review was to critically evaluate the biomechanical outcomes of different fixation constructs for a variety of biceps tenodesis techniques in cadaveric models based on both type of fixation and location.

METHODS

A PROSPERO-registered systematic review (CCRD42018109243) of the current literature was conducted with the terms "long head of biceps" AND "tenodesis" AND "biomechanics" and numerous variations thereof in the PubMed, Embase, and Cochrane databases, yielding 1,460 abstracts. After screening by eligibility criteria, 18 full-text articles were included. The individual biomechanical factors evaluated included ultimate load to failure (in newtons), stiffness (in newtons per millimeter), and cyclic displacement (in millimeters). After reviewing the included literature, we performed a quality analysis of the studies (Quality Appraisal for Cadaveric Studies scale score) and a meta-analysis comparing raw mean differences in data between the suprapectoral and subpectoral fixation location groups, as well as between the fixation construct groups.

RESULTS

Among the 18 included studies, 347 cadaveric specimens were evaluated for ultimate load to failure, stiffness, and cyclic displacement when comparing both location (suprapectoral vs subpectoral) and tenodesis fixation type (interference screw vs cortical button, suture anchor, or all-soft-tissue techniques). Interference screw fixation showed significantly greater mean stiffness by 8.0 N/mm (P = .013) compared with the other grouped techniques but did not show significant differences when evaluated for ultimate load to failure and cyclic displacement (P = .28 and P = .18, respectively). Additionally, no difference in construct strength was seen when comparing the fixation strength of suprapectoral versus subpectoral techniques for stiffness, ultimate load to failure, and cyclic loading (P = .47, P = .053, and P = .13, respectively).

CONCLUSIONS

In this meta-analysis, no significant biomechanical differences were found when the results were stratified by specific surgical technique (interference screw vs other tenodesis techniques) and location (suprapectoral vs subpectoral biceps tenodesis).

CLINICAL RELEVANCE

As a result of this study, when biomechanically evaluating specific tenodesis constructs, the individual clinician has the liberty of choosing the fixation technique based on his or her preference and knowledge of shortcomings of each type of fixation construct.

Are Implant Choice and Surgical Approach Associated With Biceps Tenodesis Construct Strength? A Systematic Review and Meta-regression

BACKGROUND

Despite the increasing use of biceps tenodesis, there is a lack of consensus regarding optimal implant choice (suture anchor vs interference screw) and implant placement (suprapectoral vs subpectoral).

PURPOSE/HYPOTHESIS

The purpose was to determine the associations of procedural parameters with the biomechanical performance of biceps tenodesis constructs. The authors hypothesized that ultimate failure load (UFL) would not differ between sub- and suprapectoral repairs or between interference screw and suture anchor constructs and that the number of implants and number of sutures would be positively associated with construct strength.

STUDY DESIGN

Meta-analysis.

METHODS

The authors conducted a systematic literature search for studies that measured the biomechanical performance of biceps tenodesis repairs in human cadaveric specimens. Two independent reviewers extracted data from studies that met the inclusion criteria. Meta-regression was then performed on the pooled data set. Outcome variables were UFL and mode of failure. Procedural parameters (fixation type, fixation site, implant diameter, and numbers of implants and sutures used) were included as covariates. Twenty-five biomechanical studies, representing 494 cadaveric specimens, met the inclusion criteria.

RESULTS

The use of interference screws (vs suture anchors) was associated with a mean 86 N-greater UFL (95% CI, 34-138 N; P = .002). Each additional suture used to attach the tendon to the implant was associated with a mean 53 N-greater UFL (95% CI, 24-81 N; P = .001). Multivariate analysis found no significant association between fixation site and UFL. Finally, the use of suture anchors and fewer number of sutures were both independently associated with lower odds of native tissue failure as opposed to implant pullout.

CONCLUSION

These findings suggest that fixation with interference screws, rather than suture anchors, and the use of more sutures are associated with greater biceps tenodesis strength, as well as higher odds of native tissue failure versus implant pullout. Although constructs with suture anchors show inferior UFL compared with those with interference screws, incorporation of additional sutures may increase the strength of suture anchor constructs. Supra- and subpectoral repairs provide equivalent biomechanical strength when controlling for potential confounders.

Suture anchor fixation strength in the Latarjet procedure: a biomechanical study in cadavers

BACKGROUND

The use of metallic screws for graft fixation during the Latarjet procedure is not devoid of complications. The purpose of the present cadaver study was to determine the initial strength of coracoid graft fixation using suture anchors and compare it to that of the traditional screw fixation of the graft using a fresh frozen human shoulder cadaver model.

MATERIALS AND METHODS

Twelve unpaired fresh frozen cadaver shoulders were utilized. In the first group, suture anchor fixation of the graft was used, while 3.75-mm cannulated screws were used in the second group. The specimens were then cyclically loaded from 5 to 150 N at a speed of 0.05 mm/s for 100 cycles. After cyclic loading, each specimen was then loaded at a constant rate of 0.5 mm/s until 7 mm of displacement. Cyclic elongation, peak-to-peak displacement, stiffness and maximum load were measured.

RESULTS

There were no significant differences between the traditional screw fixation and fixation using suture anchors in elongation, peak-to-peak displacement, stiffness and maximum load.

CONCLUSIONS

In this study, traditional screw fixation and fixation using suture anchors did not significantly affect biomechanical performance in a classic Latarjet procedure.

A technique for an arthroscopic proximal biceps tenodesis using a fork anchor

Pathology to the proximal biceps tendon has the potential to be a major source of pain in the shoulder, secondary to complex superior labrum from anterior to posterior (SLAP) lesions, partial biceps tears, and subluxations. In order to restore function and improve the patient's quality of life, repair of these injuries is crucial. Tenodesis has long been the ideal treatment of persistent pain caused by pathology of the proximal biceps tendon. A biceps tenodesis helps prevent biceps pain and cramping during movement and avoids the cosmetic deformity associated with a biceps tenotomy. However, the location of the tenodesis and technique of the procedure itself have been debated throughout the literature. We present an arthroscopic biceps tenodesis technique in which the tendon is secured to the implant prior to implantation into the humerus to gain complete control of the tendon and ensure adequate fixation and tension.

Subpectoral Biceps Tenodesis With PEEK Interference Screw: A Biomechanical Analysis of Humeral Fracture Risk

PURPOSE

To quantify the torsional load to fracture for subpectoral biceps tenodesis with interference screw fixation.

METHODS

We randomized 28 specimens from 14 matched-pair full-length humeri (mean age, 55.3 years) into 3 groups: (1) empty ream group (ERG), (2) screw-only group (SOG), and (3) screw-plus-biceps tendon group (SBG). In each group, 1 humerus of each matched pair was prepared according to group allocation and the contralateral humerus remained intact as a control. In the ERG, an 8-mm unicortical hole was reamed 1 cm proximal to the inferior border of the pectoralis major tendon insertion; in the SOG, the humerus was filled with an 8-mm × 12-mm PEEK (polyether ether ketone) screw; and in the SBG, the humerus was filled with a PEEK screw and the cadaveric long head of the biceps tendon. Humeri were tested under torsional displacement at a rate of 1°/s until fracture. Maximum torque, energy to maximum torque, and linear stiffness were used to assess humerus strength.

RESULTS

Compared with contralateral intact specimens, the maximum torque to fracture was reduced by 28% in the ERG (P = .005), 30% in the SOG (P = .014), and 20% in the SBG (P = .046). Energy to maximum torque was similarly reduced in the ERG (P = .007), SOG (P = .023), and SBG (P = .049). Stiffness was increased by 4% in the ERG (P = .498), 9% in the SOG (P = .030), and 4% in the SBG (P = .439).

CONCLUSIONS

Drilling an 8-mm unicortical hole in zone 3 of the bicipital tunnel for open subpectoral biceps tenodesis reduces the torsional load to humeral fracture up to 28% at time 0. The addition of a PEEK tenodesis screw alone reduced the maximum torque by 30%, and the addition of a screw with the long head of the biceps tendon reduced the maximum torque by 20%. The total load to fracture was reduced in all settings. Stiffness was not significantly different for the ERG and SBG, but stiffness was significantly higher for the SOG compared with the intact matched humeri at time 0.

CLINICAL RELEVANCE

When performing a biceps tenodesis, humeral fracture susceptibility is increased with an applied torsional load at time 0. Thus providers must be aware of this reduced integrity when a subpectoral biceps tenodesis is used.

A Prospective Randomized Study Comparing the Interference Screw and Suture Anchor Techniques for Biceps Tenodesis

BACKGROUND

Several methods are used to perform biceps tenodesis in patients with superior labrum-biceps complex (SLBC) lesions accompanied by a rotator cuff tear. However, limited clinical data are available regarding the best technique in terms of clinical and anatomic outcomes.

PURPOSE

To compare the clinical and anatomic outcomes of the interference screw (IS) and suture anchor (SA) fixation techniques for biceps tenodesis performed along with arthroscopic rotator cuff repair.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 2.

METHODS

A total of 80 patients who underwent arthroscopic rotator cuff repair with SLBC lesions were prospectively enrolled and randomly divided according to the tenodesis method: the IS and SA groups. Functional outcomes were evaluated with the visual analog scale (VAS) for pain, American Shoulder and Elbow Surgeons (ASES) score, Simple Shoulder Test (SST), Constant score, Korean Shoulder Score (KSS), and long head of the biceps (LHB) score at least 2 years after surgery. The anatomic status of tenodesis was estimated using magnetic resonance imaging or ultrasonography, and the anatomic failure of tenodesis was determined when the biceps tendon was not traced in the intertubercular groove directly from the insertion site of the IS or SA.

RESULTS

Thirty-three patients in the IS group and 34 in the SA group were monitored for more than 2 years. All postoperative functional scores improved significantly compared with the preoperative scores (all P < .001) and were not significantly different between the groups, including the LHB score (all P > .05). Nine anatomic failures of tenodesis were observed: 7 in the IS group and 2 in the SA group ( P = .083). In a multivariate analysis using logistic regression, IS fixation ( P = .003) and a higher (ie, more physically demanding) work level ( P = .022) were factors associated with the anatomic failure of tenodesis significantly. In patients with tenodesis failure, the LHB score ( P = .049) and the degree of Popeye deformity by the patient and examiner ( P = .004 and .018, respectively) were statistically different compared with patients with intact tenodeses.

CONCLUSION

Care must be taken while performing biceps tenodesis in patients with a higher work level; IS fixation appears to pose a higher risk in terms of the anatomic failure of tenodesis than SA fixation, although functional outcomes were not different.

Biomechanical evaluation of the long head of the biceps brachii tendon fixed by three techniques: a sheep model

OBJECTIVE

To evaluate the biomechanical properties of the fixation of the long head of the biceps brachii into the humeral bone with suture anchors, interference screw, and soft tissue suture, comparing strength, highest traction load, and types of fixation failure.

METHODS

Thirty fresh-frozen sheep shoulders were used, separated into three groups of ten for each technique. After fixation, the tendons were subjected to longitudinal continuous loading, obtaining load-to-failure (N) and displacement (mm).

RESULTS

The mean load-to-failure for suture anchors was 95 ± 35.3 N, 152.7 ± 52.7 N for interference screw, and 104.7 ± 23.54 N for soft tissue technique. There was a statistically significant difference (p < 0.05), with interference screw demonstrating higher load-to-failure than suture anchor fixation (p = 0.00307) and soft tissue (p = 0.00473). The strength of interference screw was also superior when compared with the other two methods (p = 0.0000127 and p = 0.00000295, respectively). There were no differences between suture anchors and soft tissue technique regarding load-to-failure (p = 0.9420) and strength (p = 0.141).

CONCLUSION

Tenodesis of the long head of the biceps brachii with interference screw was stronger than the suture anchors and soft tissue techniques. The other two techniques did not differ between themselves.

Which Is Better for Arthroscopic Tenodesis of the Long Head of the Biceps: Soft Tissue or Bony Interference Fixation?

PURPOSE

To compare the outcome between arthroscopic soft tissue tenodesis (STT) at the rotator interval and bony interference fixation tenodesis (BIFT) at the distal bicipital groove for the long head of the biceps (LHB).

METHODS

Twenty-five shoulders that underwent arthroscopic STT of the LHB were compared with 28 shoulders that underwent arthroscopic BIFT using a 5.5-mm Bio-Tenodesis screw (Arthrex, Naples, FL). American Shoulder and Elbow Surgeons scores, Constant score, and elbow flexion strength index (EFSI) were checked preoperatively, postoperative 1 year and 2 years. Ultrasound imaging evaluation took place at 1 year and 2 years postoperatively as well.

RESULTS

The overall functional outcomes improved after surgery in both groups. The BIFT group showed a significant increase in EFSI (preop: 0.54, postoperative 2 years: 0.94) compared with that of the STT group (preop: 0.52, postoperative 2 years: 0.74) at postoperative 2 years (P = .006). However, no significant difference was seen in the increase of American Shoulder and Elbow Surgeons scores and Constant scores between the two groups. At postoperative 2 years, ultrasound showed seven empty grooves in the STT group, but only two empty grooves in the BIFT group (P = .046).

CONCLUSIONS

Arthroscopic BIFT for the LHB showed better improvement in EFSI than arthroscopic STT. In addition, the STT group showed a higher failure rate than the BIFT group.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Arthroscopic suprapectoral and open subpectoral biceps tenodesis: a comparison of restoration of length-tension and mechanical strength between techniques

PURPOSE

This study aimed to (1) evaluate the ex vivo restoration of the long head biceps length-tension for both arthroscopic suprapectoral biceps tenodesis (ASPBT) and open subpectoral biceps tenodesis (OSPBT) techniques and (2) assess how location in the proximal humerus affects pullout strength for tenodesis using an interference screw implant.

METHODS

Eighteen matched cadaveric shoulders were randomized to OSPBT or ASPBT groups (9 each). Tenodesis was performed using clinical techniques. Preoperatively, a metallic bead was placed in the biceps tendon and a fluoroscopic image was obtained. Postoperatively, an image was obtained to evaluate the location of the tenodesis and the metallic bead and determine tensioning. Biomechanical load-to-failure testing was then performed.

RESULTS

The ASPBT technique resulted in an average of 2.15 ± 0.62 cm of biceps overtensioning compared with 0.78 ± 0.35 cm (P < .001) in the OSPBT group. The average load to failure in the ASPBT group was 138.8 ± 29.1 N compared with 197 ± 38.6 N (P = .002) in the OSPBT group. Failure caused by implant pullout was significantly more frequent in the ASPBT group (7 of 9) than in the OSPBT group (1 of 9).

CONCLUSIONS

The described ASPBT technique using an interference screw implant has the tendency to overtension the biceps and has a significantly decreased ultimate load to failure compared with an open subpectoral technique in matched cadaveric specimens.

CLINICAL RELEVANCE

This study shows differences in the biomechanical properties of OSPBT and ASPBT. Modification of currently published ASPBT techniques may be necessary to improve restoration of the physiological length-tension relationship of the biceps. Clinical studies may need to clarify if the lower ultimate load to failure for the ASPBT technique is clinically significant.

Suprapectoral biceps tenodesis: a biomechanical comparison of a new "soft anchor" tenodesis technique versus interference screw biceps tendon fixation

BACKGROUND

The interference screw technique is commonly used in tenodesis of the long head of the biceps for its well-documented robust fixation strength. Some complications may occur after tenodesis with interference screw such as persistent pain, bone fracture and cyst formation. A new technique using a small "soft anchor" has been proposed to avoid the risk of occurrence of the above-mentioned complications associated with the use of the interference screw. However, the proposed technique must provide adequate fixation strength. This study investigated the mechanical performance of the new technique and compared it with interference screw fixation.

METHODS

Fourteen human humeri and proximal biceps were tested after tenodesis using the two techniques. The fixation constructs were cycled 500 times between 20N and 100N at 1Hz to simulate some level of post-operative physical activity. Then, a tensile test to failure was performed to determine the strength of the two tenodesis constructs.

FINDINGS

The ultimate strength was 238N (SD 96N) and 172N (SD 58N) for the "soft anchor" and the interference screw, respectively (P=0.14). In two out of seven repetitions in both groups, failure occurred at low load level due to inaccuracies in performing tenodesis. Considering these cases as outliers, the strength values increased up to 290N (SD 40N) and 202N (SD 32N) for the "soft anchor" and the interference screw, respectively (P=0.02).

INTERPRETATION

The "soft anchor" technique provides a fixation strength comparable with the interference screw, but without using a screw. It could be considered as an alternative for suprapectoral biceps tenodesis.

Arthroscopic tenodesis through positioning portals to treat proximal lesions of the biceps tendon

Abstract

Arthroscopic biceps tenodesis is a good choice for treating proximal lesions of the biceps tendon. However, there are few descriptions of the surgical approach. We introduce a technique for proximal biceps tenodesis using positioning portals and placing suture anchors. Our patients had a minimum of 12 months of follow-up. Between January 2010 and June 2012, a total of 49 patients (21 men, 28 women) underwent arthroscopic biceps tenodesis. The pathology was mainly associated with proximal lesions of the biceps tendon, with the diagnosis confirmed in all patients. Patients were evaluated preoperatively and then up to and including the final follow-up. Their pain and conditions were assessed using the Constant, American Shoulder and Elbow Surgeons (ASES), and University of California at Los Angeles (UCLA) scores for pain; range of active forward flexion; and active range of motion. All data were analyzed statistically. All patients were operated on successfully. They achieved good healing during the follow-up (mean 14 months; range 12–34 months). Before surgery the ASES, Constant, and UCLA scores were 17.0, 39.4, and 15.4, respectively. After surgery they were 33.6, 89.1, and 31.2, respectively. The scores had significantly improved: ASES scores from 17.0 to 33.6 (P < 0.05); Constant scores from 39.4 to 89.1 (P < 0.05); UCLA scores from 15.4 to 31.2 (P < 0.05). Arthroscopic tenodesis through positioning portals to treat proximal lesions of the biceps tendon produces satisfactory clinical outcomes. This technique is convenient and safe.

Level of evidence

Level IV, Case Series, Treatment Study.

Long head of the biceps tendon allis clamp evaluation technique

Disorders of the long head of the biceps brachii are a common finding in conjunction with other causes of shoulder pathology. Nonoperative means as first-line treatment are often successful; however, surgery can be indicated for refractory tendinopathy. There is debate as to the best surgical treatment of the long head of the biceps tendon (LHBT) with different types of arthroscopic and open techniques. The decision on what treatment option to perform is often made at the time of surgery after arthroscopic evaluation of the LHBT. Certain examples of tendon disease are easily visible intra-articularly; however, a large portion of the tendon is not intra-articular and not readily viewed during routine arthroscopy. This study describes a simple arthroscopic technique for evaluation of an increased portion of the LHBT using an Allis clamp. The clamp is inserted through the anterior portal, placed around the LHBT, and rotated such that the tendon is wrapped around itself, bringing the distal tendon into the joint for arthroscopic viewing. This procedure is a routine part of our assessment of the LHBT during arthroscopy.