Summary

The onlay modification of the dynamic anterior stabilization utilizing the all-arthroscopic method of fixation of the long head of the biceps tendon (LHB) with all-suture anchors and the double double-pulley technique produces good clinical results and successful healing of the LHB and is safe for the treatment of anterior glenohumeral instability with less than 20% GBL at 1-year minimum follow-up

Abstract

Background

The dynamic anterior stabilization (DAS) with the long head of the biceps tendon (LHB) is a new arthroscopic soft-tissue procedure for the treatment of anterior glenohumeral instability with limited to subcritical glenoid bone loss (GBL). Few studies have reported the results of different arthroscopic methods of transposing and fixing the LHB tendon to the anterior glenoid rim. The purpose of the current study was to report the results of the onlay DAS for the treatment of anterior glenohumeral instability with less than 20% GBL. The hypothesis was that the onlay modification of the DAS that utilizes the all-arthroscopic method of fixation of the LHB with all-suture anchors and the double double-pulley (DDP) technique would produce good clinical results and successful healing of the transposed LHB and would be safe for the treatment of anterior glenohumeral instability with less than 20% GBL.

Methods

From 2018 to 2021, patients with anterior glenohumeral instability and less than 20% GBL were enrolled in a prospective study on DAS and followed-up to 48 months. The primary outcomes were: Western Ontario Shoulder Instability Index (WOSI), Rowe score, range of motion, strength. The secondary outcomes were ability to return to play (RTP), RTP at same level, lack of recurrence of instability, successful LHB healing, and lack of complications. Magnetic resonance imaging (MRI) was used to measure GBL, Hill-Sachs interval, glenoid track, and assess LHB integrity.

Results

Eighteen consecutive patients underwent the DAS. Fifteen patients had a minimum follow-up of 12 months (mean, 23.93 ± 13.67 months). 12 were male, 3 female; 73.3% practiced recreational sports; mean age at surgery, 23.40 ± 6.53 years; mean number of dislocation episodes, 10.13 ± 8.42; mean GBL, 8.21±7.39% (range, 0–20.24%); mean Hill-Sachs interval, 15.00 ± 2.96mm; mean glenoid track, 18.87 ± 2.57mm; mean Beighton score, 1.13 ± 2.80 points; 33.3% had a concomitant SLAP lesion type I or II. The mean improvement in the WOSI and Rowe score (959.27 ± 386.70 and 74.00 ± 22.22 points) was significant (p<0.001 and p<0.001) and more than 6 and 7 times higher than the minimum clinically important difference, respectively. The mean improvement in active elevation, abduction, external and internal rotation, and strength (23.00±27.76º, 33.33±43.78º, 8.33±13.58º, 0.73±1.28 points, and 1.89 ± 3.11 Kg) was significant (p=0.006, p=0.011, p=0.032, p=0.044, and p=0.034). RTP rate was 93.33%. RTP at same level was 60.00%. One severely hyperlax patient (Beighton 8) had an atraumatic redislocation episode at 8 months postoperatively. Therefore, the recurrence rate of anterior instability in the overall group was 6.7%. No complications were reported in the overall group. The MRI of each patient showed successful LHB healing to the glenoid bone at a mean follow-up period of 9.36 ± 5.66 M (range, 6.02 – 25.35 M).

Conclusions

The onlay modification of the DAS using the LHB and the DDP technique produces significant and clinically important improvements in shoulder function, successful LHB healing, and is safe for the treatment of anterior glenohumeral instability with less than 20% GBL, with or without SLAP lesions, without severe hyperlaxity.