Modified scarf osteotomy for hallux valgus: From a finite element model to clinical results

PURPOSE

Finite element (FE) analysis and clinical follow-up were used to evaluate the efficacy of modified scarf osteotomy for moderate-to-severe hallux valgus (HV).

METHOD

We retrospectively evaluated 42 patients (44 feet) who underwent modified rotational scarf osteotomy for moderate-to-severe HV at our institution between January 2010 and January 2019. Radiological indicators and subjective scores were recorded at different time points. To compare the results and elemental characteristics, a FE model of the metatarsophalangeal (MTP) joint that included anatomically realistic geometrical and structural characteristics was built. The biomechanical features and correction differences in dynamic loads as well as the incidence of troughing were estimated.

RESULTS

Both the hallux valgus angle (HVA) and intermetatarsal angle (IMA) showed significant improvement 6 weeks postoperatively (p < 0.05); additionally, the HVA increased from 6 weeks postoperatively to the last follow-up, while the IMA showed no significant changes (p > 0.05). The subjective scores significantly improved from the preoperative period to the last follow-up. The percentages of troughing and recurrence were remarkably low in our pilot study because of the innate stability of the modified rotated fixation.

CONCLUSION

Our preliminary findings suggest that modified rotational scarf osteotomy offers sufficient stability, correct HV deformity effectively, and good clinical outcomes for moderate to severe HV.

Lateral Column Lengthening for Revision Triple and Double Arthrodesis and Severe End-Stage Flatfoot Deformity

Few options exist for the treatment of revision and severe cases of end-stage flatfoot deformity. Triple arthrodesis or medial-approach double arthrodesis have been the standard but often do not provide enough correction of the deformity. Lateral column lengthening is a powerful procedure performed either with an Evans calcaneal osteotomy or calcaneocuboid distraction arthrodesis that can be used as an adjunct in realigning the flatfoot. We performed a retrospective radiographic review and looked at 11 consecutive cases of patients who underwent hindfoot arthrodesis with a lateral column lengthening procedure. We matched these patients with 11 control patients who underwent isolated medial-approach double arthrodesis. For the patients who underwent a lateral column lengthening procedure, we found a significant improvement in calcaneal inclination angle (p = .001) and greater correction in talar declination angle, cuboid abduction angle, and talocalcaneal angle when compared with the control group. Lateral column lengthening is a useful adjunct to hindfoot arthrodesis in the correction of revision and severe end-stage flatfoot deformity.

Results of Achilles Tendon Excision for Purpose of Wound Closure: Case Series

The loss of Achilles tendon results in reduced plantar flexion strength; however, in patients who are not fit for major reconstructive surgery, with soft-tissue defects overlying the tendon, Achilles tendon excision is a useful adjunct procedure for wound closure. We report 3 patients with infections around the Achilles tendons needing debridement procedures who underwent Achilles tendon excision for the purpose of wound closure. Local healing was achieved in all patients; all returned to their premorbid ambulatory status, and 2 could perform heel raise. Our series showed that Achilles tendon excision eases soft-tissue reconstruction around it and that the primary aim of wound closure was met with a reasonable functional outcome. As such, it is a viable option for selected patients with infections around the Achilles tendon who are poor candidates for flaps.

Triplanar Quantitative Radiographic Analysis of the First Metatarsal-Phalangeal Joint in the Hallux Abductovalgus Deformity

Although hallux abductovalgus (HAV) is widely considered to be a triplanar deformity involving the transverse, sagittal, and frontal planes, most of the published literature has focused on evaluating the deformity in only the transverse plane, and we are unaware of any investigation objectively evaluating the relationship among the 3 planes in the setting of HAV deformity. The objective of this investigation was to quantitatively evaluate radiographic measurement of the relationship between the transverse, sagittal, and frontal planes in the HAV deformity. Anteroposterior, lateral, and sesamoid axial radiographs from 42 consecutive feet were evaluated with measurement of the first intermetatarsal angle, hallux abductus angle, metatarsal sesamoid position, first metatarsal inclination angle, sesamoid rotation angle, and tibial sesamoid grade. Variables were graphically depicted against each other on frequency scatter plots with calculation of a regression line and Pearson's correlation coefficient. As transverse plane deformity increased, the frontal plane deformity also tended to increase and the first metatarsal inclination angle tended to decrease. And as frontal plane deformity increased, the first metatarsal inclination angle tended to decrease. To our knowledge, these are the first quantitative and objective data in support of a triplanar component to the HAV deformity, and we believe this reinforces the evaluation of this deformity with emphasis on all 3 planes.