Resurfacing arthroplasty using interpositional graft offers potential advantages over conventional TSA, including the ability to biologically resurface the glenoid, in addition to biologic or nonbiologic resurfacing of the humeral head, thereby avoiding complications of TSA in cases of bipolar disease.
Several options are available for glenoid resurfacing. Interpositional grafts may be secured over the glenoid, thereby offering a biologic surface that articulates with the humeral head. The use of a lateral meniscus as a biologic interpositional graft in the glenoid has been described using both open and arthroscopic techniques [36
]. Studies have shown that the lateral meniscus provides better glenohumeral coverage with reduced peak forces and contact stress compared to the medial meniscus in the shoulder [39
]. Other examples of biological interpositional resurfacing of the glenoid include Achillestendon allograft, autogenous fascia lata, anterior shoulder capsule, the Restore patch (DePuy Orthopaedics, Warsaw, IN, USA), and the GraftJacket (donated human skin; Wright Medical Technology, Arlington, TN, USA).
Krishnan and colleagues published a prospective study analyzing biologic resurfacing of the glenoid using a variety of interpositional tissues for grafts, including Achillestendon allograft (18 shoulders), anterior capsule (7 shoulders), and autogenous fascia lata (11 shoulders) [40
]. Their early results were comparable to results of TSA without the inherent risks of arthroplasty, with significant increases in mean ASES scores in 31 of 36 patients and no revisions for humeral component loosening. They suggested that Achillestendon allograft is the preferred graft type for biologic resurfacing. In a study of six patients, Burkhead and Hutton performed porous-coated humeral head hemiarthroplasty along with glenoid resurfacing using autogenous fascia lata or anterior shoulder capsule and found good or excellent results in all patients after two years [36
]. Others have reported good results after arthroscopic glenoid resurfacing using the Restore patch, an implant made of porcine small intestine submucosal cells with potentially pluripotent properties, with the hope of regenerating viable chondrocytes and a matrix of hyaline cartilage on the surface of the glenoid [41
]. Finally, Bhatia described an arthroscopic procedure for resurfacing the glenoid with the GraftJacket, a regenerative tissue matrix consisting of processed 1 to 2
mm thick human donor skin that retains native proteins, collagen, and vascular channels [37
However, not all authors have reported favorable results following hemiarthroplasty combined with biologic interposition, particularly at longer-term followup. Nicholson et al. recently published a series of thirty young, high-demand patients with bipolar defects who were treated with a biologic interpositional lateral meniscus glenoid allograft and uncemented hemiarthroplasty [42
]. Their short-term results overall were good, with all patients demonstrating significant improvement in outcome scores after 18 months. However, they did report a 17% complication rate within the first year, all requiring reoperation, as well as two patients with graft failure requiring conversion to a polyethylene glenoid component [42
]. Others have also shown comparable findings. Elhassan and colleagues performed a review of 13 patients with an average age of 34 years and average followup of 48 months undergoing soft-tissue resurfacing of the glenoid with a concomitant humeral head arthroplasty. The authors found that ten of the thirteen patients required a revision total shoulder arthroplasty at a mean of 14 months postoperatively and concluded that the procedure has poor outcomes in patients under 50 years [43
]. Verma et al. also noted a high clinical failure rate (51.2%) in 45 patients undergoing biologic resurfacing of the glenoid with lateral meniscus allograft or human acellular dermal tissue matrix [44
]. An unacceptably high failure ultimately led the authors to recommend against the procedure's utility in young, active patients with glenohumeral arthritis.
These aforementioned techniques are currently investigational in nature and may serve as a temporal bridge for young or middle-aged active patients who are not yet candidates for TSA. Long-term studies demonstrating success and failure rates are currently lacking, as are randomized, controlled trials comparing biologic resurfacing techniques with hemiarthroplasty, TSA, or other palliative restorative procedures.