Centre of Rotation of the Human Subtalar Joint Using Weight-Bearing Clinical Computed Tomography

Abstract Purpose Osteotomies represent well-established treatment-options for the redistribution of loads and forces within and around the knee-joint. Effects of these osteotomies on the remaining planes and adjacent joints are not fully understood. The aim of this study was to determine the influence of a distal-femoral-rotation-osteotomy on the coronal alignment of the ankle. It was hypothesized that supracondylar-external-rotation-osteotomy of the distal femur leads to a change in the coronal orientation of the ankle joint. Methods Long-leg standing radiographs and CT-based torsional measurements of 27 patients undergoing supracondylar-rotational-osteotomy of the femur between 2012 and 2019 were obtained and utilized for the purpose of this study. Postoperative radiographs were obtained after union at the osteotomy-site. The hip-knee-ankle-angle (HKA), the mechanical-lateral-distal-femur-angle (mLDFA), and Tibia-Plafond-Horizontal-Orientation-Angle (TPHA) around the ankle were measured. Comparison between means was performed using the Wilcoxon-Mann–Whitney test. Results Twenty-seven patients with high femoral antetorsion (31.3° ± 4.0°) underwent supracondylar-external-rotation-osteotomy. The osteotomy led to a reduced antetorsion (17.4 ± 5.1; p < 0.001) and to a valgisation of the overall limb-alignment. The HKA decreased by 2.4° ± 1.4° (p < 0.001). The TPHA decreased by 2.6° (p < 0.001). Conclusions Supracondylar external rotation osteotomy of the femur leads to lateralization of the weight bearing line at the knee and ankle due to valgisation of the coronal limb alignment. The mobile subtalar joint has to compensate (inversion) for the resulting valgus orientation of the ankle to ensure contact between the foot and the floor. When planning a rotational osteotomy of the lower limb, this should be appreciated – especially in patients with a preexisting valgus alignment of the lower extremities or restricted mobility in the subtalar joint.

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Evaluation of Tarsal Navicular Stress Fracture Fixation Using Intraoperative O-arm Computed Tomography

Foot & Ankle Specialist ◽

10.1177/1938640014532130 ◽

2014 ◽

Vol 7 (6) ◽

pp. 515-521 ◽

Cited By ~ 4

Author(s):

Andrew R. Hsu ◽

Simon Lee

Keyword(s):

Computed Tomography ◽

Stress Fracture ◽

Guide Wire ◽

Weight Bearing ◽

Fracture Site ◽

Stress Fractures ◽

Functional Impairments ◽

Intraoperative Ct ◽

Intraoperative Computed Tomography ◽

Anatomic Reduction

Stress fractures of the tarsal navicular are high-risk injuries that can result in displacement, avascular necrosis, malunion, and nonunion. Delayed diagnosis and improper treatment can lead to long-term functional impairments and poor clinical outcomes. Increased shear stress and decreased vascularity in the central third of the navicular can complicate bony healing with often unpredictable return times to activity using conservative management in a non-weight-bearing cast. There recently has been increasing debate regarding the effectiveness of treatment options with a trend toward surgical management to anatomically reduce and stabilize navicular stress fractures in athletes. However, anatomic reduction and fixation of the navicular can be difficult despite direct visualization and intraoperative fluoroscopy. We report a case of a chronic navicular stress fracture in a high-level teenage athlete treated with open reduction internal fixation (ORIF) and calcaneus autograft using intraoperative computed tomography (CT) (O-arm®, Medtronic, Minneapolis, MN) for real-time evaluation of fracture reduction and fixation. Intraoperative CT was fast, reliable, and allowed for confirmation of guide wire orientation, alignment, and length across the fracture site. Anatomic fixation of navicular stress fractures can be challenging, and it is important for surgeons to be aware of the potential advantages of using intraoperative CT when treating these injuries. Levels of Evidence: Therapeutic, Level IV: Case Report

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Clinical Examples of Weight Bearing Computed Tomography

Weight Bearing Cone Beam Computed Tomography (WBCT) in the Foot and Ankle ◽

10.1007/978-3-030-31949-6_22 ◽

2019 ◽

pp. 265-303

Author(s):

Martinus Richter ◽

Francois Lintz ◽

Cesar de Cesar Netto ◽

Alexej Barg ◽

Arne Burssens ◽

...

Keyword(s):

Computed Tomography ◽

Weight Bearing

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Measurements in Weight Bearing Computed Tomography

Weight Bearing Cone Beam Computed Tomography (WBCT) in the Foot and Ankle ◽

10.1007/978-3-030-31949-6_21 ◽

2019 ◽

pp. 255-263

Author(s):

Cesar de Cesar Netto

Keyword(s):

Computed Tomography ◽

Weight Bearing

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Bone Mineral Density of the Tarsals and Metatarsals With Reloading

Physical Therapy ◽

10.2522/ptj.20070226 ◽

2008 ◽

Vol 88 (6) ◽

pp. 766-779 ◽

Cited By ~ 5

Author(s):

Mary Kent Hastings ◽

Judy Gelber ◽

Paul K Commean ◽

Fred Prior ◽

David R Sinacore

Keyword(s):

Computed Tomography ◽

Bone Mineral Density ◽

Case Report ◽

Fracture Risk ◽

Bone Mineral ◽

Weight Bearing ◽

Quantitative Computed Tomography ◽

Case Description ◽

Mineral Density ◽

Lateral Column

Background and PurposeBone mineral density (BMD) decreases rapidly with prolonged non–weight bearing. Maximizing the BMD response to reloading activities after NWB is critical to minimizing fracture risk. Methods for measuring individual tarsal and metatarsal BMD have not been available. This case report describes tarsal and metatarsal BMD with a reloading program, as revealed by quantitative computed tomography (QCT).Case DescriptionA 24-year-old woman was non–weight bearing for 6 weeks after right talocrural arthroscopy. Tarsal and metatarsal BMD were measured with QCT 9 weeks (before reloading) and 32 weeks (after reloading) after surgery. A 26-week progressive reloading program was completed. Change scores were calculated for BMD before reloading and BMD after reloading for the total foot (average of all tarsals and metatarsals), tarsals, metatarsals, bones of the medial column (calcaneus, navicular, cuneiforms 1 and 2, and metatarsal 1), and bones of the lateral column (calcaneus, cuboid, cuneiform 3, and metatarsals 2–5). The percent differences in BMD between the involved side and the uninvolved side were calculated.OutcomesBefore reloading, BMD of the involved total foot was 9% lower than that on the uninvolved side. After reloading, BMD increased 22% and 21% for the total foot, 16% and 14% for the tarsals, 29% and 30% for the metatarsals, 14% and 15% for the medial column bones, and 28% and 26% for the lateral column bones on the involved and uninvolved sides, respectively. After reloading, BMD of the involved total foot remained 8% lower than that on the uninvolved side.DiscussionThe increase in BMD with reloading was not uniform across all pedal bones; the metatarsals showed a greater increase than the tarsals, and the lateral column bones showed a greater increase than the medial column bones.

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Talar process fractures

EFORT Open Reviews ◽

10.1302/2058-5241.3.170040 ◽

2018 ◽

Vol 3 (3) ◽

pp. 85-92 ◽

Cited By ~ 6

Author(s):

Haroon Majeed ◽

Donald J. McBride

Keyword(s):

Subtalar Joint ◽

Avulsion Fracture ◽

Weight Bearing ◽

Cartilage Damage ◽

Flexor Hallucis Longus ◽

High Clinical Suspicion ◽

Significant Disability ◽

Missed Diagnosis ◽

And Inversion

Fractures of the lateral and the posterior processes of the talus are uncommon and frequently missed because of a low level of suspicion and difficulty in interpretation on plain radiographs. Missed fractures can lead to persistent pain and reduced function. Lateral process fractures are usually a consequence of forced dorsiflexion and inversion of fixed pronated foot. These are also commonly known as snowboarder’s fractures. The posterior process of the talus is composed of medial and lateral tubercles, separated by the groove for the flexor hallucis longus tendon. The usual mechanism of injury is forced hyperplantarflexion and inversion causing direct compression of the posterior talus, or an avulsion fracture caused by the posterior talofibular ligament. CT scans are helpful in cases of high clinical suspicion. There is a lack of consensus regarding optimal management of these fractures; however, management depends on the size, location and displacement of the fragment, the degree of cartilage damage and instability of the subtalar joint. Non-operative treatment includes immobilization and protected weight-bearing for six weeks. Surgical treatment includes open reduction and internal fixation or excision of the fragments, depending on the size. Fractures of the lateral and the posterior processes of the talus are uncommon but important injuries that may result in significant disability in cases of missed diagnosis or delayed or inadequate treatment. Early diagnosis and timely management of these fractures help to avoid long-term complications, including malunion, nonunion or severe subtalar joint osteoarthritis. Cite this article: EFORT Open Rev 2018;3:85-92. DOI: 10.1302/2058-5241.3.170040

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