Posttraumatic Cubitus Varus: Respect the Columns

Posttraumatic cubitus varus is a multiplanar deformity that results from an improperly reduced supracondylar humerus fracture. The prevention of posttraumatic cubitus varus hinges on the stable restoration of all 3 columns of the distal humerus while avoiding malrotation. The collapse of any column leads to varying degrees of deformity in the coronal, sagittal, and/or axial plane. The purpose of this article is to explain the pattern of the deformity and use this to summarize preventative tactics for avoiding its described sequelae. We also summarize, illustrate, and present case examples for the various osteotomies used to correct the deformity, and speculate future directions.

How Risky Are Risk Factors? An Analysis of Prenatal Risk Factors in Patients Participating in the Congenital Upper Limb Differences Registry

Purpose

Risk factors for congenital upper limb differences (CoULDs) are often studied at the general population level. The CoULD registry provides a unique opportunity to study prenatal risk factors within a large patient sample.

Methods

All patients enrolled between June 2014 and March 2020 in the prospective CoULD registry, a national multicenter database of patients diagnosed with a CoULD, were included in the analysis. We analyzed self-reported, prenatal risk factors, including maternal smoking, alcohol use, recreational drug use, prescription drug use, gestational diabetes mellitus (GDM), and gestational hypertension. The outcome measures included comorbid medical conditions, proximal involvement of limb difference, bilateral involvement, and additional orthopedic conditions. Multivariable logistic regression was used to analyze the effect of the risk factors, controlling for sex and the presence of a named syndrome.

Results

In total, 2,410 patients were analyzed, of whom 72% (1,734) did not have a self-reported risk factor. Among the 29% (676) who did have at least 1 risk factor, prenatal maternal prescription drug use was the most frequent (376/2,410; 16%). Maternal prescription drug use was associated with increased odds of patient medical comorbidities (odds ratio [OR] = 1.43, P = .02). Gestational diabetes mellitus was associated with increased odds of comorbid medical conditions (OR = 1.58, P = .04), additional orthopedic conditions (OR = 1.51, P = .04), and proximal involvement (OR = 1.52, P = .04). Overall, reporting 1 or more risk factors increased the odds of patient comorbid medical conditions (OR = 1.42, P < .001) and additional orthopedic conditions (OR = 1.25, P = .03).

Conclusions

Most caregivers (72%) did not report a risk factor during enrollment. However, reporting a risk factor was associated with patient medical and orthopedic comorbidities. Of note, GDM alone significantly increased the odds of both these outcome measures along with proximal limb differences. These findings highlight the ill-defined etiology of CoULDs but suggest that prenatal risk factors, especially GDM, are associated with a higher degree of morbidity.

Type of study/level of evidence

Prognostic III.

Postburn Contractures of the Elbow and Heterotopic Ossification

Postburn contractures of the elbow are uncommon debilitating sequelae of severe burn injuries, which result from thermal injury to both deep and superficial tissues. When periarticular heterotopic bone forms in association with burn injuries, severe and rigid contractures may develop that prohibit basic functions of daily living and are often refractory to nonoperative intervention. Surgical intervention is aimed at releasing or excising all pathologic anatomy limiting elbow motion. In patients with proper indications, surgical intervention can result in substantial improvement in elbow motion, allowing patients to return to activities of daily living, employment, and recreational activities.

Arterial Anatomy of the Posterior Tibial Nerve in the Tarsal Tunnel

BACKGROUND

Both vascular and compression etiologies have been proposed as the source of neurologic symptoms in tarsal tunnel syndrome. Advancing the understanding of the arterial anatomy supplying the posterior tibial nerve (PTN) and its branches may provide insight into the cause of tarsal tunnel symptoms. The purpose of this study was to describe the arterial anatomy of the PTN and its branches.

METHODS

Sixty adult cadaveric lower extremities (thirty previously frozen and thirty fresh specimens) were amputated distal to the knee. The vascular supply to the PTN and its branches was identified, measured, and described macroscopically (the thirty previously frozen specimens, prepared using a formerly described debridement technique) and microscopically (the thirty fresh specimens, processed using the Spälteholz technique).

RESULTS

On both macroscopic and microscopic evaluation, the PTN and the medial and lateral plantar nerves were observed to have multiple entering vessels within the tarsal tunnel. On microscopic evaluation, a vessel was observed to enter the nerve at the bifurcation of the PTN into the medial and lateral plantar nerves in twenty-two (73%) of the thirty specimens. There was a significant difference (p < 0.05) in vascular density between the PTN and each of its branches.

CONCLUSIONS

The abundant blood supply to the PTN and its branches identified in this study is consistent with observations of other peripheral nerves. This rich vascular network may render the PTN and its branches susceptible to nerve compression related to vascular congestion. The combination of vascular and structural compression may also elicit neurologic symptoms.

CLINICAL RELEVANCE

Advancing the understanding of the arterial anatomy supplying the PTN and its branches may provide insight into the cause and treatment of tarsal tunnel syndrome.

Arterial anatomy of the tibialis posterior tendon

BACKGROUND

Tibialis posterior tendon dysfunction is a common disorder leading to pain, deformity, and disability, although its pathogenesis is unclear. A vascular etiology has been proposed, but there is controversy regarding the existence of a hypovascular region that may render the tendon vulnerable. The purpose of this study was to provide a description of the arterial anatomy supplying the tibialis posterior tendon.

METHODS

Sixty adult cadaveric lower extremities were obtained from a university-affiliated body donation program. Thirty specimens obtained within 72 hours of death were used for microscopic analysis. Thirty specimens were previously frozen and used for macroscopic analysis. The tibialis anterior, tibialis posterior, and peroneal arteries were injected with India Ink and Ward's Blue Latex. The specimens used for macroscopic analysis were debrided with sodium hypochlorite to expose the extratendinous anatomy. For the microscopic analysis, the tendon was cleared using a modified Spälteholz technique to expose the intratendinous vascular anatomy.

RESULTS

Macroscopically, an average of 2.5 ± 0.7 vessels entered the tendon proximal to the navicular insertion. In all, 28/30 (93.3%) specimens had a vessel entering 4.1 ± 0.6 cm proximal to the medial malleolus and 24/30 (80.0%) specimens had a vessel entering 1.7 ± 0.9 cm distal to the medial malleolus. Microscopically, an average of 1.9 ± 0.3 vessels entered each tendon proximal to the navicular insertion. In total, 27/30 (90%) specimens had a vessel entering the tendon 4.8 ± 0.8 cm proximal to the medial malleolus and 30/30 (100%) specimens had a vessel entering the tendon 1.9 ± 0.8 cm distal to the medial malleolus. In all specimens, a hypovascular region was observed, starting 2.2 ± 0.8 cm proximal to the medial malleolus and ending 0.6 ± 0.6 cm proximal to the medial malleolus with an average length of 1.5 ± 1.0 cm. The insertion of the tendon was well vascularized both on microscopic and macroscopic specimens.

CONCLUSION

The tibialis posterior tendon was supplied by 2 vessels entering the tendon approximately 4.5 cm proximal and 2.0 cm distal to the medial malleolus. A retromalleolar hypovascular region was observed.

CLINICAL RELEVANCE

Improved understanding of the vascularity of the tibialis posterior tendon may be helpful in clinical practice and potentially provides a basis for further evaluation of the causative factors of tibialis posterior tendinopathy.