Effects on the metatarsophalangeal joint after simulated first tarsometatarsal joint arthrodesis

Kinematic Analysis of Sequential Partial-Midfoot Arthrodesis in Simulated Gait Cadaver Model

BACKGROUND

Primary tarsometatarsal (TMT) arthrodesis is gaining popularity in the surgical treatment of Lisfranc injuries. However, few studies have evaluated biomechanical effects of TMT arthrodesis. The purpose of this study was to compare the kinematics of joints adjacent to the midfoot during simulations of stance before and after sequential arthrodesis of the first, second, and third TMT joints.

METHODS

Ten midtibia cadaveric specimens were loaded on a 6-degree-of-freedom robotic gait simulator. Motion capture cameras were used to collect joint kinematics throughout simulations of the stance phase. Simulations were performed for the intact and sequential arthrodesis conditions of the first, second, and third TMT joints. The sagittal, coronal, and transverse plane rotational kinematics of the intact condition were compared to kinematics after each sequential arthrodesis condition.

RESULTS

Sequential arthrodesis of the first and second TMT joints had no significant effect on ankle, subtalar, talonavicular, and first metatarsophalangeal joint motion during simulated stance when compared to the intact condition. In contrast, inclusion of the third TMT joint into the sequential arthrodesis significantly increased subtalar inversion (P = .032) in late stance and increased range of motion values in the ankle and subtalar joints by 2.1 degrees (P = .009) and 2.8 degrees (P = .014), respectively.

CONCLUSION

Sequential primary arthrodesis induced changes to ankle and adjacent joint kinematics during stance phase simulations, although not until the third TMT joint was included into the primary arthrodesis. The significant changes to kinematics due to arthrodesis of the first, second, and third TMT joints were small.

CLINICAL RELEVANCE

The minimal changes in sagittal, coronal, and transverse plane rotational kinematics support the positive clinical outcomes reported in the literature for primary partial arthrodesis of Lisfranc injuries. The inclusion of the third TMT joint should be done judiciously.

First tarsometatarsal joint derotational arthrodesis--a new operative technique for flexible hallux valgus without touching the first metatarsophalangeal joint

No operative technique for hallux valgus has been introduced in which the first metatarsophalangeal joint is not touched. We report the first tarsometatarsal joint derotational arthrodesis in which we mimic the function of the peroneus longus tendon without involving the first metatarsophalangeal joint, allowing function of the windlass mechanism without interference. We treated 66 patients (62 women and 4 men) with 84 flexible hallux valgus feet using our new operative technique. Preoperative and postoperative follow-up weightbearing radiographs were evaluated. Most patients had a pronation type foot (78%) preoperatively, and mean correction in hallux valgus and intermetatarsal angle was 20° and 9°, respectively (p < .001). The LaPorta classification showed a median change of 2.5 U (p < .001). We have described a new operative technique for flexible hallux valgus. The first tarsometatarsal joint derotational arthrodesis showed notable correction angles in hallux valgus, although the first metatarsophalangeal joint was left intact.

Evaluation and biomechanics of the first ray in the patient with limited motion

Adequate first ray function is essential to healthy human gait. Controversies still exist about aspects of human structure and function and many newer answers and theories have been proposed by a new generation of experts. Examples include the sagittal plane facilitation, tissue stress, and preferred movement pathway theories. This article also presents a summary of how to provide a thorough, detailed, and accurate first ray examination on the individual with limited motion. This article explores functional first ray mechanics in both a theoretic and biomechanical perspective, as well as a practical, hands-on examination perspective.

Reconstruction After Malunited Lisfranc Injuries

Symptomatic secondary osteoarthritis of the Lisfranc joints due to malunion following Lisfranc joint fracture dislocations or ligamentous lesions at the Lisfranc and innominate joint level generally lead to a painful functional loss and a substantial disturbance of the walking performance. Initially missed or inadequately addressed primary lesions still represent the major source of Lisfranc joint malunions. Neuro-osteoarthropathic disorders may also become manifest in the Lisfranc joint region and may be mistaken for truly posttraumatic consequences. Secondary osteoarthritis may be combined with typical multiplanar deformities. The concept of a corrective arthrodesis includes restoration of stable physiologic axes and length proportions of the foot columns. A standardized approach to analyze the clinical picture and corresponding pathomorphology and the transfer into a comprehensive surgical concept which respects the realignment of any component of deformity is a prerequisite for a good functional outcome and a high degree of patient satisfaction. A fusion limited to the medial three rays combined with a soft tissue release may be sufficient for a favorable outcome in the majority of cases and preserve the mobility of the two lateral rays.