Comparison of the Mechanical Characteristics of a Universal Small Biplane Plating Technique Without Compression Screw and Single Anatomic Plate With Compression Screw

Rates of Lapidus Procedures in the US Military Before and After the Advent of and Advocacy for Tri-Plane Lapidus Corrective Surgery

Tri-plane corrective Lapidus surgery has been described as advantageous with respect to its anatomic basis and outcomes. Because the procedure has been broadly publicized, changes in overall Lapidus procedure rates due to increased numbers of patients opting for the tri-plane approach could have occurred. Data supporting this possibility appears lacking. We employed official personnel and health records of the total active-duty US military to conduct a retrospective cohort study of Lapidus surgery rates before and after the advent of the tri-plane corrective Lapidus procedure. Least-squares and locally-weighted scatterplot smoother regression functions were used to confirm time trends. Sociodemographic and occupational traits of Lapidus patients were compared using 2-sided t tests and chi square tests. Lapidus surgery rates among hallux valgus patients decreased during 2014 to 2016 and increased during 2017 to 2021. While multiple factors might explain these trends, they coincide with the advent of and advocacy for tri-plane Lapidus surgery. The results support the possibility that its rise influenced overall Lapidus rates in this population. As these findings represent limited evidence of such an influence, further research is required to confirm a causal link. If such a link is found, and if the ongoing research suggests that superior outcomes are associated with tri-plane Lapidus surgery, substantial implications could exist for this population. Benefits might include enhanced medical readiness due to the importance of lower extremity function during military duties. Additional research is needed to confirm the impact of the procedure and to determine whether Lapidus surgery rate patterns in civilian populations mirror these findings.

One- and Two-Year Analysis of a Five-Year Prospective Multicenter Study Assessing Radiographic and Patient-Reported Outcomes Following Triplanar First Tarsometatarsal Arthrodesis With Early Weightbearing for Symptomatic Hallux Valgus

We report one- and 2-year results of a prospective, 5-year, multicenter study of radiographic, clinical, and patient-reported outcomes following triplanar first tarsometatarsal arthrodesis with early weightbearing. One-hundred and seventeen patients were included with a mean (95% confidence interval [CI]) follow-up time of 16.6 (15.5, 17.7) months. Mean (95% CI) time to weightbearing in a boot walker was 7.8 (6.6, 9.1) days, mean time to return to athletic shoes was 45.0 (43.5, 46.6) days, and mean time to return to unrestricted activity was 121.0 (114.5, 127.5) days. There was a significant improvement in radiographic measures with a mean corrective change of -18.0° (-19.6, -16.4) for hallux valgus angle, -8.3° (-8.9, -7.8) for intermetatarsal angle and -2.9 (-3.2, -2.7) for tibial sesamoid position at 12 months (n = 108). Additionally, there was a significant improvement in patient-reported outcomes (Visual Analog Scale, Manchester-Oxford Foot Questionnaire, and Patient-Reported Outcomes Measurement Information System) and changes were maintained at 12 and 24 months postoperatively. There was 1/117 (0.9%) reported recurrence of hallux valgus at 12 months. There were 16/117 (13.7%) subjects who experienced clinical complications of which 10/117 (8.5%) were related to hardware. Of the 7/117 (6.0%) who underwent reoperation, only 1/117 (0.9%) underwent surgery for a nonunion. The results of the interim report of this prospective, multicenter study demonstrate favorable clinical and radiographic improvement of the HV deformity, early return to weightbearing, low recurrence, and low rate of complications.

Can we correct first metatarsal rotation and sesamoid position with the 3D Lapidus procedure?

OBJECTIVE

We examine the technique and radiographic outcomes obtained with triplanar first tarsometatarsal arthrodesis (3D Lapidus) for the surgical correction of hallux valgus (HV). This procedure, apart from correcting angular deformity 1st-2nd intermetatarsal angle, HV angle, etc., is specifically intended to act on first ray pronation and place the sesamoids in their normal position, to alleviate the metatarsalgia often occurring in HV before and after surgery, possibly caused by their abnormal position. This study aims to examine the radiographic outcomes of the 3D Lapidus procedure.

MATERIALS AND METHODS

Retrospective study of 37 feet operated on from April 2019 to December 2019, with a minimum 1-year follow-up (mean 420 days), using the 3D Lapidus procedure. Radiographic outcomes were evaluated.

RESULTS

The intermetatarsal angle decreased from a mean value of 16.42° to 5.62° (p < 0.0001). The HV angle decreased from a mean value of 32.12° to 8.05° (p < 0.0001). The preoperative first metatarsocuneiform angle, with a mean value of 21.86°, was null after arthrodesis (p < 0.0001). The tibial sesamoid position, according to the Hardy and Clapham classification, decreased from a mean value of 4.84 to 1.27 after surgery, within normality (p < 0.0001).

DISCUSSION

Correction of the deformity in a single plane is generally insufficient. It is necessary to act on the three planes of space to correct the deformity, obtain good outcomes, and avoid recurrence.

CONCLUSIONS

Radiographic outcomes of triplanar correction with the 3D Lapidus procedure are excellent, achieving statistically significant differences in all parameters studied.

Triplanar Correction for First Metatarsophalangeal Fusion

Successful deformity correction utilizing first metatarsophalangeal (MTP) fusion for hallux valgus with concomitant degenerative changes of the first MTP joint is well documented. Currently, there is limited discussion in the literature focusing on triplanar correction of the first MTP arthrodesis. Presented is a novel approach for triplane correction and fusion of the first MTP joint utilizing a biplanar locked plating system.

Biomechanical Performance of Charcot-Specific Implants

Over the past 2 decades, an increased number of diabetic Charcot neuroarthropathy reconstructions have been performed. Despite advances in implant technology, arthrodesis complication rates remain high. This study examined the biomechanical properties (4-point bending, cantilever bending, and thread pullout resistance) of intramedullary implants designed for midfoot reconstruction. Large implants included A1 (7.4 mm cannulated stainless steel beam), B1 (6.5 mm solid titanium bolt), and C1 (7.0 mm cannulated titanium beam). Smaller implants included A2 (5.4 mm cannulated stainless steel beam) and C2 (5.0 mm solid titanium bolt). Four-point bending testing compared flexural properties of the body of the implants. Cantilever-bending testing was performed with the maximum bending moment being applied off the main thread of the implant to assess the thread portion. Thread pullout strength was tested by fixing the implants to a Sawbone block on a platform, and the distal portion of the implant in a clamp connected to loading actuator. Implant A1 demonstrated higher stiffness, force to failure, and fatigue compared to implants B1 and C1 (p < .05). Pullout strength of implant A1 was higher than implant B1 (p < .05). Thread fatigue strength of implant A1 was higher than implant C1 (p < .05). Implant A2 demonstrated higher stiffness, force to failure, tip fatigue strength, and thread pullout strength compared to implant C2 (p < .05), while implant C2 demonstrated higher body fatigue failure than implant A2 (p < .05). Alteration of beam/bolt parameters influences the biomechanical performance of implants used in Charcot reconstruction. Greater stiffness resists deformation, providing improved stability. Greater static failure load and fatigue limit improves the implant's ability to withstand higher and repetitive loads before failing This study should stimulate further clinical research to determine if these biomechanical properties translate into reduced implant failure rates and improved clinical outcomes in patients with diabetic Charcot neuroarthropathy.

Progression of Healing on Serial Radiographs Following First Ray Arthrodesis in the Foot Using a Biplanar Plating Technique Without Compression

A review of 195 first ray arthrodeses fixated with a twin-plate biplanar construct, without interfragmentary compression, is presented. This fixation construct was evaluated in a consecutive cohort of patients undergoing first metatarsophalangeal joint (MTP) arthrodesis or the first tarsometatarsal joint (TMT) arthrodesis. Multiple radiographs were used to assess the progression of healing at the following postoperative time frames: 4 to 9 weeks, 10 to 12 weeks, >12 weeks, and the final follow-up. In total, 85 feet underwent first MTP arthrodesis, and 110 feet underwent first TMT arthrodesis. At the final radiographic follow-up, 97.44% of all cases had shown progressive osseous gap filling at the arthrodesis site, stable position of the bone segments, and intact hardware without loosening, 98.24% of the first MTP arthrodesis group and 96.82% of the first TMT arthrodesis group. Five (5.43%) feet had the presence of lucency at the fusion interface at the final follow-up, without positional change or hardware failure. Four (1.8%) feet had a failure of the hardware, loss of position, or frank gapping at the fusion site. Lucency decreased consistently over time in this series of patients (p < .00001). Progressive increase in callus density at the fusion site on serial radiographs was noted to be a consistent finding for both procedures and was the primary indicator of secondary bone healing at the noncompressed, relatively stable arthrodesis site. Our results confirm that biplanar plating construct without interfragmentary compression produces high fusion rates following the first MTP or TMT arthrodesis, with early weightbearing.

Biomechanical Characteristics of Biplane Multiplanar Tension-Side Fixation for Lapidus Fusion

Although plating on the plantar, tension-side of the metatarsocuneiform joint provides an inherent biomechanical advantage for Lapidus arthrodesis, it has not been widely adopted owing to the morbidity associated with plantar application. To overcome these limitations, a modification to 90-90 locked biplanar plating was developed to provide the biomechanical advantages of multiplanar fixation and tension-side fixation, allowing application through a conventional incision. We tested the hypothesis that biplanar plating with tension-side fixation (low-profile straight dorsal plate and anatomic medial-plantar plate) would demonstrate improved mechanical stability compared with a previously tested 90-90 biplanar construct (small straight plate dorsally and medially) under cyclic loading. Both constructs were tested in static load to failure (3 pairs) and cyclic loading (10 pairs) with plantar cantilever bending using surrogate anatomic bone models. With static ultimate failure, the biplanar plate construct with tension-side fixation failed at a significantly greater failure load than did the straight biplanar plate construct (247.3 ± 18.4 N versus 210.9 ± 10.4 N; p = .04). With cyclic failure testing, the biplanar plate construct with tension-side fixation endured a significantly greater number of cycles (206,738 ± 49,103 versus 101,780 ± 43,273; p < .001) and a significantly greater dynamic failure load (207.5 ± 24.3 N versus 162.5 ± 20.6 N; p < .001) compared with the straight biplanar plate construct. These results have demonstrated that under simulated static and cyclic Lapidus arthrodesis loading, biplanar plating with tension-side fixation provides superior strength compared with the straight biplanar construct. Thus, this construct shows promise for clinical application as a practical approach to tension-side fixation and an early return to weightbearing after Lapidus fusion.

Hallux Valgus Deformity and Treatment: A Three-Dimensional Approach: Modified Technique for Lapidus Procedure

In a hallux valgus deformity, the problem is deviation of the hallux at the metatarsophalangeal joint and of the first metatarsal at the tarsometatarsal joint. Although anterior-posterior radiograph findings have been prioritized, deviation in the other planes can substantially change visible cues. The modified technique for Lapidus procedure procedure, uses all 3 planes to evaluate and correct the deformity, making radiographic measurements less useful. Using a triplane framework and focusing on the apex of the deformity, all bunions become the same modified technique for Lapidus procedure can be performed regardless of the degree of deformity, always includes triplane correction, and deformity size becomes irrelevant.