Arthroscopic bone block using an autologous iliac crest graft and concomitant remplissage for severe bipolar bone loss in a young patient with anterior shoulder instability: a case report

Anterior shoulder instability, common in young males, is often associated with Bankart lesions, bony Bankart lesions, and Hill-Sachs defects. Repeated instability can erode the anterior glenoid rim, predisposing to further dislocations. Treatments address glenoid deficiency by augmenting the anterior wall with bone. Hill-Sachs lesions (HSLs), depending on size, can engage during external rotation, increasing dislocation risk. Large HSLs may be treated with remplissage, using the infraspinatus tendon and capsule to cover the defect and converting it from intraarticular to extra-articular.³¹ Combining remplissage with a free bone technique significantly reduces recurrent dislocation rates in a cadaveric biomechanical study.⁹ Clinical cases operated with this procedure are rare, and to our knowledge, there is no other case described in the literature besides a technical note and a small prospective study.^1,8

Case report

A 19-year-old male mechanic sought a second opinion for his right shoulder after multiple anterior dislocations, first occurring at age 17. Initial injury included a reversible axillary nerve injury. Despite physiotherapy after each event, he experienced 5 more dislocations during sports. Imaging showed a Hill-Sachs defect, irregular anterior glenoid rim (Fig. 1), old osseous Bankart lesion, and a large (1.6 cm width × 2.5 cm length) off-track HSL¹⁷ (Fig. 2). The circle method in computer tomography revealed a significant anteroinferior glenoid defect of 25% of the glenoid surface with a more medially displaced fragment of the former glenoid rim, Type II according to Scheibel²⁶ and large HSL (Fig. 3).

Figure 1.

Preoperative (A) anteroposterior showing the medially displaced glenoid rim fragment and (B) Y-view revealing the HSL. HSL, Hill-Sachs lesion.

Figure 2.

Preoperative coronal (A) and sagittal (B) T2-weighted MRI. (A) The arrows indicate an HSL and an anterior glenoidal bone loss and labral tear. (B) The image indicates an HSL. HSL, Hill-Sachs lesion; MRI, magnetic resonance imaging.

Figure 3.

Preoperative coronal CT. The arrow indicates the bone loss on the anterior glenoid rim and residual dislocated bony fragment. CT, computer tomography.

Following a thorough discussion with the patient regarding the range of available techniques, it was decided that the optimal approach would be an arthroscopic free autologous bone block from the iliac crest and a labral repair, accompanied by a remplissage to cover the big HSL.

Technique description

The patient was positioned in a left lateral decubitus position. At the beginning the procedure involved the grafting of the bone block from the iliac crest. Initially, a posterior portal was utilized for diagnostic arthroscopic surgery. The medial dislocation and malunion of the old fracture, as well as the presence of a grade III (Calandra) HSL, were identified during the diagnostic procedure. The surgical intervention involved the addition of 2 anterior portals and 2 posterolateral portals. Following the observation of the HSL through one of the posterolateral portals, the affected zone was trimmed with a ball bur and 2 y-knot-RC-anchors (CONMED, Largo, USA) were placed via the same portal but separate tendinocapsular passages superiorly and inferiorly (Fig. 4). The anterior rim and the scapula neck were meticulously prepared, and the defect was measured precisely to ensure the iliac crest autograft was appropriately prepared at 2.3 cm × 1.2 × 0.8 (height × length × width). The width of the graft was used to repair the anterior–posterior side of the glenoid defect, while the length was used to repair the mediolateral side. The graft was fixed in place using a FiberTape-Cerclage (Arthrex, Naples, FL, USA), after 2 3.0 mm drill holes were drilled from posterior to anterior and the rotator interval was opened. Once in place, the graft was tightened with the tensioner and the Tapes and back-up knots were performed. The anteroinferior capsule and the labrum were fixed with 2 1.4 mm Iconix anchors (Stryker, Kalamazoo, MI, USA) (Fig. 5, A). With a double pulley-system the sutures of the remplissage were tightened and the infraspinatus tendon with capsula fixed in the HSL, which disappeared under arthroscopic view (Fig. 5, B). The arthroscopic portals were closed in accordance with standard practice.

Figure 4.

Intraoperative arthroscopic identification (A) of the HSL and positioning of the 2 y-knots anchors (CONMED) (B). HSL, Hill-Sachs lesion.

Figure 5.

Intraoperative arthroscopic bone block (A) and closure of the remplissage (B).

Outcome and follow-up

Follow-ups at 6 weeks, 3 months, 6 months, 2 years, and 2 and a half years showed substantial improvement. At 3 months, the patient had minimal discomfort and improved range of motion (ROM). At 2 years, the patient demonstrated an ROM of 170° of flexion and abduction, 80° of external rotation (see Fig. 6), and an abduction force of 10 kg, symmetrical to the contralateral side. The Western Ontario Shoulder Instability Score was documented at 200, the Rowe Score at 75, the subjective shoulder value score at 98%, and the Constant score at 91. Imaging confirmed the bone block remained in place at two years (Figs. 7 and 8) with slight reabsorption of the peripheral regions according to Wolff's law³¹ and restoration of the osseous anterior glenoid width.

Figure 8.

Postoperative CT axial and 3D reconstruction (A), axial and 3D reconstruction after 6 months (B) and axial and 3D reconstruction after 2 years (C). The arrows indicate the autologous bone block on the anterior glenoid rim. 3D, 3-dimensional; CT, computer tomography.

Figure 7.

Six week postoperative (A) anteroposterior and (B) axial view with a centered joint and the bone block on the anterior glenoid.

Discussion

This case report demonstrates the efficacy of an arthroscopic Bankart with an arthroscopic bone augmentation of the anterior glenoid wall, in conjunction with an additional remplissage procedure. The decision to perform this combination of surgical procedures was multimodal and included the specific instability history of the patients, his pathoanatomic bony condition, the age and soft tissue conditions as well as the patient's extensive sporting activity.

Anterior shoulder dislocation is a condition that typically affects young individuals who exhibit a generalized degree of soft tissue laxity^21,28,30,3 or shoulder hypermobility.^11,14,30 However, it is important to note that the condition can also occur as a result of traumatic injuries, irrespective of the individual's age.⁴ A reliable diagnostic workup of the dislocation is imperative, as the treating physician must initially consider a wide variety of potential bone, labrum, rotator cuff, other soft tissue and even the nerve injuries (the n. axillaris and the n. radialis).²⁰ The patients frequently exhibit a painful ROM and/or a positive anterior apprehension test¹⁴ and in numerous cases, they demonstrate recurrent dislocations. These factors collectively impede their daily activities and sporting pursuits. Magnetic resonance imaging remains the gold standard due to its high levels of sensitivity and specificity. In the absence of significant soft tissue injuries or bony defects, the initial dislocation that is pain-free is often managed nonoperatively, particularly when compared to traumatic events that result in recurrent dislocation and substantial labral or bony defects.^3,16

The patient's case is characterized by recurrent anterior shoulder dislocations, accompanied by a malunioned bony Bankart and a deficient glenoid. However, there is an absence of significant generalized soft tissue laxity.

The following operative procedures are at the surgeon's disposal when it comes to surgical treatment of anteroinferior shoulder instability: the arthroscopic Bankart, the Bristol-Latarjet procedure, various glenoid augmentation techniques, and remplissage.^2,10,24 There are a number of different types of bony block procedures. These include autografts, such as iliac crest grafts, the Bristol-Latarjet operation using the tip of the coracoid and the conjoint tendon, and allografts, including tibial allografts and J-span grafts.⁶ The redislocation rate following the Bankart operation alone is reported to range between 7.5% and 40%^{7,16,18,23,27} with higher rates observed in athletes and individuals engaging in sports that involve overhead movements, as well as in cases of off-track lesions.¹⁶

This case report demonstrates the efficacy of an arthroscopic Bankart with an arthroscopic bone augmentation of the anterior glenoid wall, in conjunction with an additional remplissage procedure. The decision to perform this combination of surgical procedures was made in light of the patient's extensive sporting activity, which resulted in a favorable outcome. Fixing the iliac crest bone block with suture cerclages provides improved graft-glenoid contact loading, and good short-term clinical outcomes have been demonstrated.^12,25

In 2022, Jonathan J. Callegari published a biomechanical study in Arthroscopy⁵ that utilized 9 cadavers as subjects. The study demonstrated that the incorporation of remplissage to the free bone block procedure led to the restoration of translation and stiffness in the subjects' shoulders. The same observation was articulated in an editorial commentary by Michael D. Feldman in the 2022 issue of Arthroscopy.⁹ Other studies suggest that Bankart repair alone does not provide sufficient stability and should be performed alongside an additional procedure.^13,32 The analysis of the dimension and position of the HSL are crucial to decide whether a surgical intervention for the HSL has to be performed. The concept of the glenoid track and the on- and off-track HSL was described by E. Itoi in 2017.¹⁷ Numerous authors have proposed that off-track lesions should be converted into on-track lesions through a remplissage procedure.^17,29 Remplissage is a treatment of choice for patients with a high risk of instability recurrence, and it can also be used in lesions that are on track to enhance stability and lower recurrence risk.^15,19,22 It has been established that certain on-track lesions, when located in close proximity to the articular surface, may be indicative of potential recurrent instability.¹⁹ In our case, we did not consider the distance to the dislocation.

As demonstrated in this case study, the patient exhibited a well-restored ROM at the 6-month postoperative stage for external rotation in addition to symmetrical force in abduction and negative anterior apprehension sign. Notably, there were no recurrent dislocation events so far till the 2-year Follow-up, which is a significant finding in this context.

Conclusion

The chronic anterior shoulder instability is a prevalent condition, yet its treatment remains challenging. A multitude of operative options are currently available. In view of the above-mentioned recurrence rates of the Bankart repair alone, there remains a need for several additional operating steps in order to enhance the success rate of the operation. The arthroscopic Bankart repair, in conjunction with the free autograft bone block from the iliac crest and the remplissage procedure, yielded a favorable outcome 2.5 years postoperatively in the present case. The outlined technique enabled the stabilization of the joint without significant impairment to the external rotation, as evidenced in the attached images (Fig. 6). The patient continued to report no recurrent dislocations, and soon after the operation stated a pain-free shoulder continuing until the present.

Figure 6.

Clinical outcome at 6 months postoperatively with flexion (A), low and high external rotation (B), and high internal rotation (C).

Disclaimers:

Funding: No funding was disclosed by the authors.

Conflicts of interest: The authors, their immediate families, and any research foundation with which they are affiliated have not received any financial payments or other benefits from any commercial entity related to the subject of this article.

Patient consent: Obtained.