Morad Chughtai, MD; Andrew Swiergosz, MD; Linsen T. Samuel, MD, MBA; and Anthony Miniaci, MD
Hill-Sachs lesions refer to bone defects resulting from posterolateral humeral head impaction against the anterior rim of the glenoid in an anterior shoulder dislocation event (Figures 13-1 and 13-2). The management of these in the athlete depends mainly on the size of the lesion and whether it is an engaging one. Although most of these lesions are small and may not necessarily be significant, when surgically addressed this is mostly indirectly performed by addressing instability at the glenoid; for example, a Bankart repair or glenoid reconstruction, which is discussed in another chapter. For the purposes of this chapter, we will specifically discuss surgical management options and techniques for bone defects of the humeral head for optimized return to play in the athlete.
Multiple techniques have been described to address symptomatic engaging Hill-Sachs lesions. Historical techniques such as rotational osteotomies are no longer or rarely used, and these techniques are associated with complications and have been largely replaced by more successful techniques.1–5 Open anterior procedures, such as a capsulorrhaphy or east-west plication, are performed to offer some stability by shifting the glenoid track medially and superiorly, which in turn limits external rotation, thereby inhibiting the humeral head defect from engaging.2,3 However, these techniques that do not use bony manipulation or augmentation may not be sufficient in the settings of large humeral head defects. Additionally, range-of-motion loss in the athlete may prevent return to play and possibly cause late arthrosis.6
For the purposes of this chapter, we will discuss the following current surgical options to address humeral head defects in shoulder instability for the athlete: 1) remplissage, 2) humeral head augmentation with autograft or allograft bone, and 3) prosthetic humeral head augmentation. Other options that are experimental or salvage procedures without enough evidence for the “athlete” that will be briefly discussed are 4) humeroplasty and 5) arthroplasty.
Remplissage is a French term that translates to “filling” or “to fill.” In terms of shoulder surgery, it describes filling the humeral head defect with tendon and capsule. By doing this, it converts the defect from intra-articular to extra-articular, thereby preventing the defect from engaging with the anterior glenoid rim, effectively turning the defect into an extra-articular defect with soft-tissue coverage to prevent engagement with the anterior glenoid rim. The procedure was originally reported by Connolly as an open procedure that involved filling the defect with transfer of the infraspinatus tendon in conjunction with a portion of greater tuberosity.7 Eventually, an all-arthroscopic technique was published by Wolf and Pollack,8 who performed a posterior capsulodesis and infraspinatus tenodesis into the humeral head defect in conjunction with standard Bankart repair (Figures 13-3 and 13-4). This is typically recommended when there is less than 25% of anterior glenoid bone loss; larger glenoid loss would require bony glenoid augmentation procedure such as the Bristow-Latarjet9 (Figures 13-5 and 13-6). Koo et al10 described using a double-pulley technique in which 2 anchors were used to insert the infraspinatus tendon into the defect, thus allowing for sutures to be tied over rather than through the tendon on the muscle belly, which in turn was a more anatomic and tissue-preserving construct (Figure 13-7). Elkinson et al11 studied the biomechanical effect of different anchor positions when performing remplissage technique in a cadaveric model. They demonstrated that among the various models, medial suture passage through the infraspinatus muscle belly consistently had the greatest mean restriction of range of motion and highest stiffness value.
Although there have been concerns about the nonanatomic nature and probable loss of motion and subsequent revision surgery, clinical outcomes have been relatively successful (Table 13-1). Several reports of the procedure reported a 7% (2 of 24) incidence of recurrent instability with maintained range of motion in all planes at 2-year follow-up.4 Zhu et al12 reported on 49 consecutive patients who underwent remplissage, and at a minimum of 2-year follow-up, they found that patients had a mean increase of 8 degrees of forward elevation and only a mean loss of 1.9 degrees of external rotation. On the basis of rheumatic review of 7 studies (levels II, III, and IV) of combined arthroscopic remplissage with Bankart repair, the pooled recurrent dislocation was 3.4%. At a mean 26-month follow-up,13 the investigators concluded there was no clinically significant loss of range of motion after remplissage. Furthermore, in 4 of the 7 studies postoperative imaging showed high rates of healing and tissue filling at the infraspinatus tenodesis. Similarly, a magnetic resonance imaging investigation of 11 patients at an average follow-up of 18 months found evidence of tendon incorporation into humeral head defect as early as 8 months.14
Boileau et al22 reported on 47 patients who underwent arthroscopic remplissage: There was a mean loss (SD) of 8 degrees (± 7 degrees) of external rotation and 9 degrees (± 7 degrees) abduction, which was not functionally limiting. However, of 41 of the 47 patients who participated in athletics before surgery, 37 (90%) returned to sport with 28 (68%) returning to the same level of sport, including overhead sports, at a mean follow-up of 2 years.
Humeral Head Augmentation With Autograft or Allograft Bone
Owing to the Hill-Sachs lesion that is created during the dislocation mechanism, techniques have been reported to restore the resulting bone loss with a goal of restoring the articular arc. This has been reportedly used in young patients who meet the surgical indications.23 There are 2 types of allograft reconstructions: size-matched bulk graft and osteochondral plug transfer (see Figures 13-6 and 13-7).
Having a size- and side-matched osteoarticular humeral head allograft is essential for optimal recreation of the radius of curvature of the humeral head (± 2 mm) (Figure 13-8). The graft is preferably one that is fresh-frozen and cryopreserved.24 Using a deltopectoral approach and capsulotomy for exposure and inspection allows for addressing abnormalities at the anteroinferior capsulolabral and glenoid complex. Once this is achieved, the Hill-Sachs lesion is shaped in a chevron fashion and the matching allograft is then cut to fit the site of the humeral head osteotomy. The allograft is then secured with a lag technique using countersunk screws (Figures 13-9 through 13-11). Some techniques have been described in the literature describing osteochondral plug transfer; however, reports are scarce.25,26