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Clinical Features, Debates & Research / DĂŠbats, recherche et articles cliniques (continued from page 45)
Clinical Indications and Recommendations Selecting the ideal candidate for biologic resurfacing must be considered carefully after weighing the available evidence. While documented case series in the literature have yielded mixed outcomes in support of BGR, the basic science and clinical literature support the use of ATen or LMA as the best available graft materials, given their intrinsic composition and subsequent biomechanical properties. Krishnan et al. have obtained the most promising results with ATen; however, other studies have yet been unable to reproduce their findings. Given the different technical approaches, it may be that a significant etiology for the failures observed by Elhassan et al. included graft preparation and subsequent fixation.
Figure 1 Arthritic glenoid prior to resurfacing. Image courtesy of Dr. S. Krishnan (Baylor University Medical Centre)
Hemiarthroplasty with Achilles Tendon (ATen) Allograft In the series by Krishnan et al., the authors utilized ATen in 18 shoulders (Table 1)8. Overall, return to function, stabilization of glenoid erosion, and avoidance of early arthroplasty were achieved (Figure 1). The authors reported no failures in the 18 shoulders treated with ATen (Figure 2). Failures, as noted above, were observed in patients treated with ACap and FL. The authors concluded ATen to be superior to ACap and FL for BGR. Elhassan et al. attempted unsuccessfully to reproduce these findings in 13 patients, utilizing ATen, ACap, or autogenous FL4. In this series, 11 out of 13 patients were treated with ATen. Unlike Krishnan et al., 91% (10/11) were revised to total shoulder arthroplasty at 14 months. It should be noted that Krishnan et al. preferred folding their grafts three times and securing the graft via transosseus sutures, whereas Elhassan et al. describe folding the graft twice and securing it to the remaining labrum4,8. This suggests that a thicker, more securely fixed graft may be a critical technical aspect of this procedure. Hemiarthroplasty with Graft Jacket Puskas et al. utilized GraftJacket secured with metal anchors6. Multiple patients in this series were revisions who had undergone from one to as many as six prior surgeries. In the setting of early failure, the authors of that study did not investigate nor comment on the possibility of infection as a reason for failure. It is possible that indolent infection, the use of a thin graft secured with metal anchors, and/or retained hardware contributed to the high failure rate. This certainly supports the hypothesis that thinner, more weakly secured grafts may be more susceptible to failure.
COA Bulletin ACO - Fall / Automne 2016
While Wirth et al. have observed promising long-term outcomes utilizing LMA, the subsequent study by Nicholson et al. was unable to reproduce such findings. However, it is possible that graft security may have contributed to the high failure rate observed in their series as well, indicating that LMA is not necessarily a poor choice for BGR. In summary, the evidence in favour of BGR continues to evolve, with graft selection and security as major technical considerations. Further studies are needed, including comparisons of surgical techniques and details. Biological resurfacing may be a viable option in the younger active patient with end-stage glenohumeral arthritis. In several studies, resurfacing has not only improved function and pain, but has allowed patients to return to activity. There are certainly concerns regarding this procedure, including durability and reproducibility4–6. However, a correctly indicated patient may benefit from BGR, provided that careful consideration is given to type of graft and security of attachment to the glenoid, insuring the biologic bearing surface remains in its intended location.
Figure 2 Glenoid after resurfacing with Achilles tendon. Image courtesy of Dr. S. Krishnan (Baylor University Medical Centre)