Lisfranc injuries, caused by low-energy and high-energy traumas, could vary from ligamentous sprains to complex fractures [1, 2]. The incidence of Lisfranc injuries was estimated to be 9.2/100,000 person-year, and men and young individuals in their third decade of life appeared to be more susceptible to the injury [1, 3]. The treatment method for Lisfranc injuries is decided based on the severity of the injuries as well as the patients’ characteristics [4, 5]. The injuries with less than subtle malalignment could be managed nonoperatively while open reduction and internal fixation (ORIF) and arthrodesis might be indicated for more severe cases ^[5]. Different instruments and implants are used for both ORIF and arthrodesis including plates, screws, K-wires, staples, and flexible fixation [6, 7]. Most of these implants are metallic and impose the need for second removal surgery on the patients aside from other complications such as loosening and breakage that can cause further psychosomatic and economic burden on the patients and the health-care system [8, 9]. Thus, resolving the need for a second operation that is provided by bio-absorbable and bio-integrative implants has become a focus of various research in orthopedic surgery ^[10]. A preclinical study on rabbit models with cylindrical bone defects in the femur showed that using bio-absorbable screws could lead to higher rates of bone healing by increasing vascularization and bone regeneration [10, 11]. While the application of bio-integrative implants is still limited, this could revolutionize the care of patients with orthopedic injuries if the implants’ built-in properties ensure a functionally stable connection between the bones and the implant surface ^[11]. The current study is a case series of 10 patients receiving bio-integrative screws for their Lisfranc injuries. Herein, we report the patient-reported outcome measures (PROMs) and the complications in these patients over at least 3 months of follow-up.

This is a retrospective case-series study on 10 adult patients with Lisfranc injury who underwent tarsometatarsal (TMT) fixation using bio-integrative screws (OSSIOfiber™). The inclusion criteria were: (1) patients with Lisfranc injury with documented instability on weight-bearing computed tomography scan when compared to the contralateral side, (2) receiving surgical fixation of TMT joint, (3) using bio-integrative implant, (4) being ≥18 years old, and (5) having at least 2 months of follow-up. The exclusion criteria were (1) patients who received metal implants, (2) concomitant injuries that affect the PROMs reported by the patient during the follow-up visits, and (3) patients who have not filled out PROMs surveys. The study protocol was approved by the institutional review board (IRB no. 2015P000464). Patients’ charts were reviewed to gather information about the treatment method, pain score (Visual Analog Scale), and reported complications in the postoperative follow-up visits. The complications we investigated were nonunion, wound dehiscence, and hardware failure (loosening or breakage). The PROMs, which were obtained during one of the patients’ follow-up visits that happened during 6-month post-surgery, were gathered from the charts. The PROMs surveys used in the current study were patient-reported outcomes measures information system (PROMIS®) short forms for PF, depression, physical health, mental health, pain interference, and pain intensity (PF-SF-10a, global health, SF-4a, and SF-3a) [12, 13]. PROMIS utilizes T-score maps to compare the patients’ scores to the general United States’ population [14, 15]. Median and IQR were used to depict the data. Statistical analysis was done using SPSS (ver. 28, IBM™) and P-value of significance was set at 0.05 where needed.

The patients’ demographic data, diagnosis, mechanism of injury, procedure, pain scores, and complications in follow-up visits are presented in Table 1. The median (IQR) age of patients with Lisfranc injury who received bio-integrative screws was 39.5 (29.2–44.2), ranging from 18 years old to 80 years old. Of these 10 patients, five were female (50%), and five were male (50%). The median (IQR) of body mass index of patients was 27.76 (24.9–37.3), with the minimum and maximum being 23.9 and 68.3, respectively. The mechanisms of injury included fall (n = 5), sports injury (n = 3), motor vehicle accident (MVA) (n = 1), and work-related injury (n = 1). All patients had TMT ORIF for Lisfranc injury. The median (IQR) of patients’ follow-up duration was 9 (4–11.5). Among the patients, nine showed promising outcomes as their pain scores evaluated in follow-up visits decreased. These patients began progressive weight-bearing, and two returned to sports (case no. 8 after 5 months and case no. 9 after 4 months). Case no. 8 was a young female squash player who came to the clinic after a twisting injury, leading to a high-grade partial Lisfranc ligament tear with 2^nd TMT subluxation (Fig. 1). The procedures done for the patient were Lisfranc ORIF, 1^st TMT ORIF, and inter-cuneiform ORIF (Figs. 2 and 3). Another patient (case no. 9) who returned to playing 4 months after the surgical procedure was an 18-year-old girl with increased space between her first and second metatarsal bones who received Lisfranc ORIF, 2^nd TMT ORIF, and inter-cuneiform ORIF. The symptoms of one patient (case no. 6) who had MVA did not improve, leading to a second surgical intervention. Case no. 6 was a patient MVA leading to multiple fractures, including metatarsal bones. First and second TMT fusions and inter-cuneiform fixation were done for the patients. However, the patient remained symptomatic and needed a second surgical intervention to remove the hardware. Table 2 represents the PROMs in patients who received Lisfranc fixation using bio-integrative screws. The median (IQR) scores of PROMs representing PF, depression, physical health, mental health, pain interference, and pain intensity were 49.5 (30.1–61.9), 41 (41–49), 50.8 (39.2–57.7), 59 (48.9–63.7), 51.7 (41.6–72.6), and 43.5 (37.8–55.2), respectively. The surveys were done in one of the patients’ post-operation follow-up visits with the median (IQR) of 3 (2.75–5.25) months.

In addition, we reported the PROMs of the Lisfranc patients who received bio-integrative screws and monitored the complications that occurred at least 2 months’ postoperatively. According to the T-score maps and the PROMs, the patients could conduct daily activities and never felt depressed during the study period. In addition, PROMIS global health scores in patients who received bio-integrative screws for Lisfranc injury shows that they were as healthy as the general population, both physically and mentally. Although with a median (IQR) Pain interference score of 51.7 (41.6–72.6), the patients had slight pain during daily and social activities, the pain intensity scores were within the normal range. In conclusion, this report is the first study evaluating the post-surgical outcomes of patients received bio-integrative screws for their TMT joint fixation. We observed that the patients who received the treatment as part of their primary Lisfranc fixation did not require any further intervention. However, as the implants are made of radiolucent materials, we needed to examine anatomical landmarks to assess the joint alignments after the surgery and during the follow-up period. Further studies with a longer-term follow-up are needed to evaluate these results.

The incidence of Lisfranc Injury is estimated to be 9.2/100,000 person-year, and young individuals in their third decade of life appeared to be more susceptible to the injury. Various methods are used for ORIF of Lisfranc injuries, and each shows different post-treatment outcomes. In the current study, 9 out of 10 patients receiving bio-integrative screw showed promising outcomes as their pain scores decreased in follow-up visits. These patients began progressive weight-bearing, and two returned to sports in <6 months. The PROMs representing of PF, depression, physical health, mental health, and pain intensity were within normal ranges during the follow-up period.

Most of the implants used for ORIF are metallic and impose the need for second removal surgery on the patients aside from other complications such as loosening and breakage that can cause further psychosomatic and economic burdens on the patients and the healthcare system. Resolving the need for a second operation that is provided by bio-absorbable and bio-integrative implants has become a focus of various research in orthopedic surgery. The current study reported the treatment outcomes of 10 patients receiving bio-integrative screws for their Lisfranc injuries.