Basic morphological characteristics of coracoid grafts obtained by open and arthroscopic Latarjet techniques: A comparative study

BACKGROUND

A knowledge of the anthropometric characteristics of the coracoid graft (CG) that can be obtained by the open and arthroscopic Latarjet techniques may be beneficial in the preoperative planning and intraoperative decision making for coracoid osteotomy and transfer. We have not found any study that compared the morphology of the CG that can be obtained from open and arthroscopic Latarjet techniques. The purpose of this study was to verify if the basic anthropometric characteristics of CGs are equivalent.

HYPOTHESIS

We hypothesize that the basic anthropometric characteristics of the CGs are similar.

METHODS

Twenty fresh-frozen human paired cadaveric shoulder specimens that had been randomly distributed in two groups of 10 specimens each were used. Two surgeons, each with experience in performing the open and arthroscopic Latarjet technique, performed these procedures in each of the respective groups (OG, open group; AG, arthroscopic group). A CT scan was performed. Using the volume rendering technique, a metric analysis of the volume, area and length of the CG were performed, evaluated and statistically analysed.

RESULTS

There were no significant differences in length (p=0.162) (mean length, 22.6mm for OG and 23.6mm for AG). There were significant differences in the volume (p=0.031) and area (p=0.007) of the CG, being lower in the OG (mean volume, 2.8 cm³ for OG and 3.6 cm³ for AG; mean area, 9.9 cm² for OG and 12.8 cm² for AG). No significant differences were observed by sex or laterality.

CONCLUSION

The mean lengths of the CGs that were obtained by each technique are equivalent. However, the areas and volumes of the grafts are different, being lower in the open surgery. These differences have not been an impediment to perform the technique. Our results corroborates that consolidation is more related to the preparation and placement than to the anthropometric characteristics of the CG. No significant differences were observed by sex or laterality.

LEVEL OF EVIDENCE

Basic Science.

Comparison of Coracoid Graft Position and Fixation in the Open Versus Arthroscopic Latarjet Techniques: A Cadaveric Study

BACKGROUND

Since the description of the arthroscopic Latarjet technique, discussion about the superiority of the open or arthroscopic procedure has arisen. The appropriate placement of the coracoid graft (CG) on the anterior glenoid neck is reported to be the most important step of the Latarjet procedure.

PURPOSE

To verify if there are differences in the parameters that may affect the final position and fixation of CG obtained from the open and arthroscopic Latarjet techniques.

STUDY DESIGN

Controlled laboratory study.

METHODS

Twenty fresh-frozen human paired cadaveric shoulder specimens were randomly distributed in 2 surgery groups (open group [OG] and arthroscopic group [AG]) with 10 specimens in each. Two surgeons, each with experience performing open and arthroscopic Latarjet techniques, executed these procedures: one surgeon performed all open techniques, and the other performed all arthroscopic techniques, respectively. After surgery, a computerized tomography scan was performed. The surgical time, the position of each CG, a series of variables that might affect the CG fixation, and the level of the subscapularis muscle split were evaluated.

RESULTS

The mean surgical time was significantly longer in the AG (mean, 26 minutes for OG and 57 minutes for AG). Three intraoperative complications (30%) were identified in the AG, consisting of graft fractures. The CG was determined to be in an optimal cranial-caudal position in 90% of specimens of the OG and 44% of the AG (Fisher, P = .057). In both groups, the CG was placed in an optimal medial-lateral position in all specimens. In the OG, the degree of parallelism between the major axes of the glenoid surface and CG was significantly greater than in the AG (mean, 3.8º for OG and 15.1º for AG). No significant differences were observed in superior and inferior screw orientation between the groups. In the longitudinal and transverse directions, significant differences were found in the centering of the superior screw, being closer to the ideal point in the OG than in the AG. The location where the longitudinal subscapularis muscle split was performed was significantly higher in the AG.

CONCLUSION

The open Latarjet technique required less surgical time; presented a lower number of intraoperative complications; and allowed more adequate placement of the CG, better centering of the screws, and a subscapularis muscle split closer to the ideal position.

CLINICAL RELEVANCE

The reported benefits of the arthroscopic Latarjet technique seem less clear if we take into account the added surgery time and complications.

Development of the long head of the biceps brachial tendon: A possible explanation of the anatomical variations

The anatomical variations of the proximal portion of the long head of the biceps brachii tendon (LHBT) are rarely observed in clinical practice. However, an increase in the rate of shoulder arthroscopic surgery has led to an increase in the observation of anatomical variations of this region. The aim of this work was to analyze the development of the LHBT in 23 human embryos ranging from the 6th to 8th weeks of development. The LHBT develops from the glenohumeral interzonal mesenchyme in the 6th week. By week 7, the myotendinous junction of the LHBT develops. The anlage of the LHBT is separated from that of the glenohumeral capsule during week 8. Our results suggest that the most important period for the LHBT development occurs between the 6th and 8th weeks of embryonic development. Alterations during this critical period may cause anatomical variations of the LHBT. An additional case report from our own experience is provided as Supplementary material.