Malfunction, power shortage, or contamination of oscillating saw, as a femoral neck osteotomy tool in THA, could happened from time to time. Re-sterilization or replacement of the instruments adds to the cost of providing the instruments and also be time consuming[8]. To the best of our knowledge, this is the first study that introduce the fretsaw as a substitute osteotomy tool in THA. This study demonstrates the satisfactory osteotomy outcomes, as well as distinct advantages, of using the fretsaw for this purpose.
Operation time is an important factor in intraoperative safety and postoperative rehabilitation of patients[9]. In the present study, there was no significant difference in osteotomy time between the fretsaw and oscillating saw groups. The fretsaw was equally efficient as a tool for femoral neck osteotomy and did not prolong the operative time. In our study, the fretsaw group achieved a satisfactory osteotomy height, which was consistent with preoperative planning. There was no significant difference in osteotomy height between the two groups. More interestingly, the deviation of the fretsaw group was lower than that of the oscillating saw group. This might be related to the saw blade swaying due to the strong reverse impact when the high-speed saw blade touches bone.
Notch generation in the femoral neck contributes to a high stress concentration during canal preparation and stem implantation, increasing the risk of Intraoperative periprosthetic femoral fracture (IOPFF)[10–12]. In our study, using a fretsaw as the femoral neck osteotomy tool resulted in a smooth osteotomy plane, and there is no occurrence of notch generation.
Blood splash occurs frequently when using an oscillating saw for femoral neck osteotomy. This puts surgeons and assistants at greater risk of infection with blood-borne diseases transmitted from the patient[7]. Furthermore, patients are also susceptible to infection due to reverse splashes, which can deflect off a surface and contaminate the surgical site[13, 14]. A surgical mask cannot provide sufficient protection against blood splash. Many surgeons neglect eye and whole face protection due to discomfort or a misty field of view[15]. In our study, no blood splash was generated when using the fretsaw as the femoral neck osteotomy tool, demonstrating another advantage to using the fretsaw for this purpose.
Our study has several limitations. Firstly, the sample size of study group was relatively small. Secondly, the fretsaw was only used as the osteotomy tool in patients with a relatively normal femoral neck, such as those with osteonecrosis of the femoral head, femoral neck fracture, hip osteoarthritis, or dysplasia of the hip (Crowe type I). Patients with more severe deformity of the femoral neck or hip ankyloses were not included.