Hand size affects branching of the deep ulnar nerve and deep palmar arch.

PURPOSE: Understanding the anatomy of the deep neurovascular structures of the hand is essential in surgical planning. There is a lack of literature regarding hand size and its influence in branching variation and the distances between branches of various neurovascular structures. Our study quantifies the variation in branching distances of the deep ulnar nerve and deep palmar arch branches. METHODS: Twenty-five fresh-frozen cadaveric hands were dissected. Each branch of the deep ulnar nerve and deep palmar arch was identified. The distance from the most distal portion of the pisiform to the proximal aspect of the branch was measured. The relationship between the length of the third metacarpal and the distance of each branch from the pisiform was examined. RESULTS: There was no relationship between branching differences in the deep ulnar nerve and the length of the third metacarpal. There was a significant association between the length of the third metacarpal and the second, third, and fourth branches of the deep palmar arch (p < 0.05). CONCLUSIONS: Our study found a significant association between the branching distances of the second, third, and fourth branches of the deep palmar arch and hand size as measured by the length of the third metacarpal.

A Type IV Extension Supracondylar Fracture With Comminuted Fracture Pattern: A Case Report.

CASE: A three year, 11 month old girl sustained a right displaced extension supracondylar fracture (ESF) of the humerus with comminution of the lateral column after an indoor fall. At surgery, fracture reduction showed multidirectional instability. Adequate reduction was achieved by applying longitudinal traction of the arm with partial elbow flexion and forearm supination. One percutaneous medial pin, followed by one lateral cross pin, was used to immobilize the fracture. Normal posterolateral new periosteal bone formation was seen on radiograph on the lateral side. At 5-year follow-up, she had full range of asymptomatic and symmetrical elbow motion. CONCLUSION: This case report shows a displaced ESF with a comminuted lateral humeral column, which contributed to a lack of adequate lateral pin purchase on bone. A modified pin fixation technique first with a medial pin and followed by a lateral pin with both placed through the medial column was used for stable fracture fixation. In addition, this case showed that fracture comminution was a contributory factor to the rare multidirectional instability of the Gartland Type IV fracture.

Advising Orthopaedic Hopefuls in the Wake of a Pass/Fail US Medical Licensing Examination Step 1: A Proposed Method for Predicting US Medical Licensing Examination Step 2 Clinical Knowledge Outcomes.

INTRODUCTION: Matching into orthopaedic residency has become difficult, and the US Medical Licensing Examination Step 1 transition to pass/fail scoring has complicated the process. Advisors' ability to mentor students has decreased, and program directors may rely on Step 2 Clinical Knowledge (CK) scores in selecting which candidates to interview. This study aims to offer a method to predict Step 2 CK outcomes based on preadmission and preclinical performance. METHODS: The study investigated 486 students from a US medical school who enrolled in 2017 and 2018. Data on demographics, preadmission, and preclinical performance were collected. Before model creation, it was found that sex, Medical College Admission Test scores, Comprehensive Basic Science Examination performance, and preclinical curriculum performance produced optimal models. Multivariate ordinal logistic regression models were built to predict probabilities of four outcome levels of Step 2 CK: <235, 235 to 249, 250 to 265, and >265. Finally, nomograms were created to visualize probability calculations. RESULTS: Each model's odds ratios revealed that female sex, higher MCAT scores, and better Comprehensive Basic Science Examination and preclinical performance were associated with an increased likelihood of being in higher Step 2 CK scoring groups. Preclinical performance had a profound effect, especially for those in the top 1/3. Models were successful in assigning higher probabilities to students in higher Step 2 CK scoring groups in more than 80% of instances. Nomograms presented provide examples of how to apply these models to an individual student. DISCUSSION: This study presents a novel method for predicting probabilities of Step 2 CK outcomes that can be used to mentor students at a time point when Step 1 previously filled this role. It may assist in identifying orthopaedic hopefuls at risk of performing poorly on Step 2 CK and can foster the development of individualized guidance and mitigation strategies.

High- Versus Low-Energy Intertrochanteric Hip Fractures in Young Patients: Injury Characteristics and Factors Associated With Complications.

OBJECTIVE: To compare fracture patterns and associated injuries for young patients with high- versus low-energy intertrochanteric hip fractures and to report on factors associated with complications after surgical fixation of high-energy fractures. DESIGN: Retrospective comparative study. SETTING: Academic Level 1 Trauma Center. PATIENTS: A total of 103 patients 50 years of age or younger were included: 80 high-energy fractures and 23 low-energy fractures. INTERVENTION: Cephalomedullary nailing (N = 92) or a sliding hip screw (N = 11). MAIN OUTCOME MEASURES: Radiographic characteristics of fracture morphology, implant position, and reduction quality and postoperative complications were the main outcome measures. RESULTS: Compared with young patients with low-energy fractures, those with high-energy fractures had more fracture comminution ( P = 0.013) and higher ISS scores ( P < 0.003) and were more likely to require open reduction ( P < 0.001). Patients with low-energy fractures from a ground-level fall had higher rates of alcohol abuse (0.032), cirrhosis (0.010), and chronic steroid use (0.048). Overall reoperation rate for high-energy fractures was 7%, including 2 IT fracture nonunions (5%) and 1 deep infection (2%). For high-energy fractures, ASA class ( P = 0.026), anterior lag screw position ( P = 0.001), and varus malreduction ( P < 0.001) were associated with malunion. Four-part fracture (OTA/AO 31A2.3/Jensen 5) ( P = 0.028) and residual calcar gap >3 mm ( P = 0.03) were associated with reoperation. CONCLUSIONS: Surgical treatment of high-energy IT fractures in young patients is technically demanding with potential untoward outcomes. Injury characteristics and severity are significantly different for young patients with high-energy IT fractures compared with low-energy fractures. For young patients with a high-energy IT fracture, surgeons can anticipate a high rate of associated injuries and complex fracture patterns requiring open reduction. For young patients with a low-energy IT fracture, comanagement with a hospitalist or a geriatrician should be considered because they may be physiologically older. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Intraosseous lipoma of the clavicle with extraosseous extension.

Intraosseous lipomas are rare primary benign bone tumors which present with highly nonspecific radiographic features that may lead to equivocal diagnoses. Advanced imaging studies such as MRI with and without contrast and, in some selected cases, tissue sample analyses are required in the diagnostic pathway. Here we describe the second case in the literature of an intraosseous lipoma of the clavicle and the first with extraosseous extension. Subsequent to histologic confirmation the lesion was monitored with clinical and radiologic evaluation.

Metastatic vertebral lesion mimicking an atypical hemangioma with negative 18F-FDG positron emission tomography-computed tomography.

Atypical hemangiomas of the spine can mimic metastatic lesions on magnetic resonance imaging, therefore making this distinction is a diagnostic challenge. In most cases, this conundrum can usually be solved with positron emission tomography/computed tomography images, because hemangiomas do not usually present with increased uptake while metastatic lesions do. Here we present a case of a patient with a unique diagnosis, myxoid liposarcoma, in which the vertebral metastatic lesion did not present with increased uptake in positron emission tomography/computed tomography scans. While keeping the imaging particularity of this rare sarcoma in mind, proceeding with a biopsy when the suspicion of metastasis remains high will help elucidate the diagnosis and allow for proper management.