Three new studies from the Hospital for Special Surgery (HSS) highlighting the use and advantages of osseointegration (OI) for individuals with amputations were presented at the 2026 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS) in New Orleans this week.
“Osseointegration represents a significant advancement in the field of prosthetics for patients who have had a limb amputation, and interest is building rapidly,” said Jason Hoellwarth, MD, director of research in the Limb Lengthening and Complex Reconstruction Service and the Osseointegration Limb Replacement Center. “At HSS, we have performed more OI surgeries than any other hospital in the United States, treating more than 300 patients since 2017. We have found that osseointegration provides improved mobility, comfort, and quality of life for patients when compared to a standard socket prosthesis.”
One of the studies, “Femur and tibia press-fit osseointegration: A comparison of safety and outcomes,” investigated OI results at different amputation levels.
“There are no studies in the scientific literature focusing on differences in safety and outcomes of patients who underwent transfemoral osseointegration as compared to those who had transtibial osseointegration,” said Taylor J. Reif, MD, an orthopedic surgeon in the Osseointegration Limb Replacement Center at HSS who presented the research. Reif and colleagues set out to compare safety, clinical, and quality-of-life outcomes in these two patient groups.
Hoellwarth, coauthor of the study, noted that OI was originally considered primarily for patients with transfemoral amputations, since they fared much worse with a socket prosthesis than individuals with transtibial amputations. “It was widely believed that patients with a below-the-knee amputation did well enough with their socket prosthesis and therefore would not derive significant benefit from osseointegration. Our study directly challenged that perspective.”
Researchers reviewed 147 OI procedures: 83 at the transfemoral level and 64 at the transtibial level. Both groups experienced substantial improvements in mobility and overall patient satisfaction, and there were no significant differences in the rate of adverse events.
“Contrary to widespread assumptions, our research found that tibia osseointegration patients have as much to gain from the surgery as femur OI patients,” Reif said. “Therefore, any individual with a lower-limb amputation who is dissatisfied with their current socket prosthesis should be evaluated for osseointegration if they would like to pursue that option.”
In the second study, HSS researchers set out to compare safety and outcomes in patients who had OI surgery performed at the same time they had an amputation versus the more commonly performed OI in individuals with an existing amputation.
The study, “Primary amputation with osseointegration versus osseointegration for existing amputation,” included patients who had lower-limb OI with a minimum of one-year follow-up at HSS. There were 139 OI procedures: 81 transfemoral and 58 transtibial. Fifteen patients had simultaneous amputation and OI (four transfemoral and 11 transtibial), while 124 patients had OI for an established amputation (77 transfemoral and 47 transtibial).
The researchers found that both groups of patients achieved comparable gains in mobility and quality of life. There was no significant difference in adverse events between the two groups.
“Our research challenges the current paradigm that individuals with amputations should first try conventional socket prosthetics and only consider osseointegration if they are dissatisfied with their prosthesis,” said Reif, who presented the study. “It would be reasonable to offer simultaneous amputation and osseointegration to select, well-informed patients who prefer to bypass the trial of a socket prosthesis.”
For the third study presented at the AAOS conference, “Safety and early experience of osseointegration limb replacement with custom-fit implants,” HSS researchers set out to review the early outcomes of OI with custom-made 3D-printed implants, which may be required for certain patients to obtain an ideal fit.
“Some designs of press-fit osseointegration implants have standard curvatures and contours with patient-specific length, leading to difficulty fitting the shape of the residual bone in some cases,” Hoellwarth said.
Reif noted that additive manufacturing using electron beam melting (EBM) allows the production of precision OI implants to achieve an optimal fit, making it possible to reconstruct nearly any residual bone segment to meet an individual’s anatomical needs.
The HSS researchers retrospectively reviewed the records of 19 patients who underwent OI with custom 3D-printed implants planned from a preoperative CT scan. Patients included those who had transfemoral, transtibial, and transradial OI procedures between May 2024 and March 2025.
The investigators found large, statistically significant improvements in patient-reported outcome scores following OI, and a significant increase in prosthetic use was observed in those who had used a socket prosthesis before OI surgery.
Reif noted that the custom EBM OI implants avoided intraoperative distal chip fracture, which can sometimes occur when using standard OI implants, and there was no loosening of the custom implants.
“We found that short-term functional outcomes were similar to standard osseointegration implants,” he added. “Further studies are warranted to assess the long-term outcomes and durability of custom implants.”
