The most common donor sites for harvesting include the iliac crest, greater trochanter, and PT. The choice of bone graft harvest site depends on the surgeons’ preference and the patient’s injured limb. However, different techniques have led to various complications and morbidity associated with the donor site in the past, necessitating the evaluation of the overall efficacy of the procedure. We must account for the quantity, quality, and morbidity of different harvest sites, especially regarding pain from the patient’s perspective.
Mauffrey et al. conducted a prospective in vivo quantification study that indicated no significant difference in the volumetric amount of cancellous bone available for harvest between the PT site and the AIC site [5]. Chiodo et al. reported histologic differences, such as osteogenic and hematopoietic progenitor cell content between the iliac bone and the tibia shaft, and that the former was superior to the latter [19]. However, Takemoto et al. reported no significant difference in the mRNA levels of all types of bone morphogenetic proteins from different harvest sites, which implies that the choice of donor site should not depend on the inherent differences in the osteoinductive and osteogenetic potential of the bony material itself [20].
Although the iliac crest is the most common donor site for autogenous cancellous bone graft, it has associated donor site morbidity as high as 7% [4, 10, 21]. In our study, regarding the incidence of harvest site morbidity, there was only one case of donor site fracture in the AIC group. Alt et al. claimed that a sufficient amount of cancellous bone can be harvested from the proximal tibial metaphysis and that the risk of postoperative fracture is not increased [22]. In our study, no harvest site morbidity was identified in the PT group.
Techniques for iliac cortex harvesting offer improvement in cosmetics and donor site pain [23]. A retrospective review that compared the morbidity associated with anterior and posterior iliac crest harvest sites found that both sites have an overall complication rate lower than those previously reported and that a posterior site has a substantially lower risk of overall postoperative complications than an anterior site (2 vs. 23%) [4]. Mauffrey et al. also assessed the response to each graft site from the patient’s perspective and reported that the pain experienced by patients after AIC grafts was higher than that at the PT or olecranon [5]. In our study, we had a similar result with the evaluation of VAS ratings on POD 1, POD 5, and POD 14, which indicated that the pain at the PT harvest site was statistically less severe than that at the AIC. Nevertheless, as the patients recovered, there was no significant difference in pain severity 1 month postoperatively between the two groups (Fig. 2).
Baumhauer et al. compared patient-reported outcomes of acute and persistent pain at 1 year after foot and ankle surgery, in which bone graft harvest site pain at 3 weeks showed more significant pain in the iliac crest than proximal tibia and calcaneus, respectively [24]. In our study, there was no significant difference between the VAS ratings on POD 28 and POD 56 of the AIC and PT groups, and only one case of harvest site fracture with hematoma was identified in the AIC group. On POD 1, there was no significant difference in the pain level at the recipient site between the two groups. This finding suggested that the postoperative pain severity in both groups was equal, but the pain was more severe with iliac crest graft harvests at early time points (POD 1, 5, and 14), although differences resolved by 4 weeks after surgery. More importantly, PT harvesting gave rise to not only less pain at the donor site for at least two postoperative weeks but also significantly less pain than that at the recipient site on POD 1 (Table 2).
The issue about the bone graft volume was ever evaluated by the syringe according to certain literatures. In our study, we harvested the bone graft as much as possible during surgery. Even the graft volume from proximal tibia was larger than the iliac crest, the proximal tibia donor site gave less complication than the iliac crest, according to the report of Salawu et al. [25], and the present study’s result showed there was less pain in the proximal tibia harvest site. The lack of comparison of quantity of harvest graft is one our limitations, and bone harvest at two sites of the same person simultaneously for the comparison of volume was also not practicable in our retrospective study. What we took into account was the comparison of pain severity between the anterior iliac crest and proximal tibia harvest sites, and the result showed less postoperative pain at the proximal harvest site for at least two postoperative weeks than at the anterior iliac crest. Besides, the pain severity of PT harvest site is less than the recipient site.
Limitations in our study included the retrospective study design, the limited sample size for each group, comparative analysis of the quantity of graft, the detailed consumption of analgesics, functional scale, clinical outcomes, and the bias of the patient’s subjective tolerance to pain. In addition, there was no evaluation of graft volume and quality or of the mechanical factors resulting from the implant choice for surgery that may influence the VAS rating at the recipient site and bone union.