Radiographic Value of the Lisfranc Diastasis in a Standardized Population.

Introduction. Injury to the Lisfranc's joint, in particular to the second metatarsal-medial cuneiform (second MMC) joint, can be difficult to evaluate, especially in subtle Lisfranc injuries. The purpose of this study was to determine the value of the Lisfranc joint width (diastasis) of the adult foot in a standardized population thereby establishing a potential reference range when investigating this area for potential injury. Methods. The 2nd MMC joint in 50 men and 50 women was evaluated. Individuals with a history of foot/ankle pain, previous foot/ankle operation or fracture, or a history of systemic disease were excluded from the study. Bilateral weightbearing digital anterior-posterior and lateral radiographs were taken using a standardized method. Results. The mean 2nd MMC diastasis in 200 feet was 5.6 mm (95% CI 5.39-5.81). In the female population, the mean 2nd MMC diastasis was 5.8 mm (95% CI 5.51-6.09) as compared with 5.6 mm (95% CI 5.31-5.89) in males. The mean distance between the fifth metatarsal base and first cuneiform in the entire study population was 16.3 mm (95% CI 15.57-17.03). Conclusion. This study helps define baseline measurements of the Lisfranc joint for the general population, which can provide a standard measurement against which suspected foot injuries can be compared.Level of Evidence: Level IV.

Comparison of Radiographic and Intraoperative Visual Assessment of Scaphotrapezoid Joint Arthritis in Patients With End-Stage Carpometacarpal Arthritis of the Thumb Base.

Background: The purpose of this investigation is to compare the radiographic and intraoperative assessment of scaphotrapezoid (ST) joint arthritis in patients with end-stage carpometacarpal (CMC) arthritis of the thumb base. We aim to define the incidence of ST arthritis in this population and determine whether radiographic features such as lunate morphology, dorsal intercalated segment instability (DISI), and scapholunate (SL) diastasis are associated with the incidence of ST arthritis. Methods: We retrospectively reviewed consecutive patients with end-stage CMC arthritis of the thumb treated operatively with trapeziectomy. Preoperative wrist radiographs were reviewed, and the presence of ST arthritis was determined using the Sodha classification. Lunate morphology, DISI, and SL diastasis were noted. Intraoperative grading of ST arthritis was assessed using a modified Brown classification. The specificity and sensitivity of radiographic assessment was compared with the gold standard of intraoperative direct visualization. Results: In total, 302 thumbs met inclusion criteria. End-stage ST joint arthritis determined by intraoperative visual inspection was noted in 31% of cases. No radiographic or demographic variables were found to be risk factors for ST arthritis. Plain radiographs were 47% sensitive and 94% specific in their ability to detect end-stage ST joint arthritis. Conclusions: We report a 31% incidence of end-stage ST joint arthritis in surgically treated patients with CMC arthritis based on visual inspection which is lower than previous literature. Wrist radiographs demonstrate a 47% sensitivity and 94% specificity in predicting end-stage ST joint arthritis. It is imperative to directly visualize the ST joint after trapeziectomy, as radiographs demonstrate poor sensitivity.

Reliability of distal tibio-fibular syndesmotic instability measurements using weightbearing and non-weightbearing cone-beam CT.

BACKGROUND: To investigate the reliability and reproducibility of syndesmosis measurements on weightbearing (WB) cone-beam computed tomography (CBCT) images and compare them with measurements obtained using non-weightbearing (NWB) images. METHODS: In this IRB-approved, retrospective study of 5 men and 9 women with prior ankle injuries, simultaneous WB and NWB CBCT scans were taken. A set of 21 syndesmosis measurements using WB and NWB images were performed by 3 independent observers. Pearson/Spearman correlation and intra-class correlation (ICC) were used to assess intra- and inter-observer reliability, respectively. RESULTS: We observed substantial to perfect intra-observer reliability (ICC=0.72-0.99) in 20 measurements. Moderate to perfect agreement (ICC=0.45-0.97) between observers was noted in 19 measurements. CONCLUSION: Measurements evaluating the distance between tibia and fibula in the axial plane 10mm above the plafond had high intra- and inter-observer reliability. Mean posterior tibio-fibular distance, diastasis, and angular measurement were significantly different between WB and NWB images.

The Optimal Location to Measure Scapholunate Diastasis on Screening Radiographs.

BACKGROUND: Lack of a universally accepted location and normal value limits the utility of measuring scapholunate diastasis. The primary purpose of this study was to define the optimal location to measure the scapholunate gap throughout sequential ligament transections. Secondary purposes were to compare plain radiographs with fluoroscopy and to evaluate interrater reliability in measuring scapholunate diastasis. METHODS: Five cadaver forearms were imaged with intact carpal ligaments and after sequentially transecting the scapholunate, radioscaphocapitate, and scaphotrapezium-trapezoid ligaments. Plain radiographs and static fluoroscopic images were obtained with wrists in neutral and 30° ulnar deviation for each stage. Multiple reviewers performed measurements of the scapholunate interval at 3 separate locations. Mean distances were calculated and pairwise comparisons between groups were made. Intraclass correlation was calculated to determine interrater reliability. RESULTS: Overall, measurements made in the middle of the scapholunate joint had the smallest margins of error for all imaging modalities, ligament disruptions, and wrist positions. For normal wrists, the mean scapholunate measurements were all less than 2.0 mm at the middle of the joint, regardless of imaging modality or wrist position. Fluoroscopy detected significance between more stages of instability than plain radiographs at the middle of the joint. CONCLUSIONS: Measurements in the middle of the scapholunate joint in neutral and 30° of ulnar deviation under fluoroscopic imaging best capture all stages of ligamentous disruptions. Measurements less than 2.0 mm at the middle of the scapholunate interval may be considered within normal range.

Surgical Management of Vertex Epidural Hematoma: Technical Case Report and Literature Review.

BACKGROUND: Vertex epidural hematoma (VEH) is an uncommon presentation of extra-axial hematomas. It can represent a surgical dilemma regarding when and how to operate, particularly considering the potential implication of the superior sagittal sinus (SSS). OBJECTIVE: Here, we illustrate the surgical technique for VEH as well as a review of the existing literature. METHODS: A 60-year-old man sustained a ground-level fall resulting in complete diastasis of the sagittal suture with underlying large VEH causing significant mass effect on the SSS and bihemispheric convexities. Twenty-four hours later, the patient deteriorated, with decreased level of alertness and worsening asymmetric paresis on his lower extremities. He subsequently underwent surgical evacuation of the hematoma, decompression of the SSS, and fracture repair. A modified bicoronal approach, with bilateral parasagittal craniotomies, was performed. A central island of bone was left intact to spare the diastatic fracture from the craniotomies. This was done to ensure a stable anchor point for tacking-up the underlying displaced dura and SSS. The central bone prevents extensive bleeding from the diastatic fracture and eliminates the risk of further blood reaccumulation and tearing of a possible injured sinus during bone flap elevation. RESULTS: The technique performed allowed us to evacuate completely the hematoma while preserving the SSS and repairing the sagittal suture to avoid further bleeding. Complete neurologic recovery of the patient occurred after VEH evacuation. CONCLUSIONS: Because of its rare nature, VEH represents a surgical challenge. Because neurosurgeons encounter this condition relatively infrequently, literature regarding the medical and surgical management of this entity is warranted.

Isolated Syndesmosis Diastasis: Computed Tomography Scan Assessment With Arthroscopic Correlation.

PURPOSE: To investigate which method can predict tibiofibular diastasis more accurately among the tibiofibular interval at the ankle joint level or previous parameters taken 1 cm above the joint line. METHODS: An arthroscopic examination was performed in 78 consecutive patients with anterolateral ankle pain. Four different methods were performed to take measurements of the tibiofibular interval using an axial computed tomography (CT) scan under existing arthroscopic diagnosis. Three previously reported parameters were assessed at 1 cm above the joint level. In the first method, 2 measurements were obtained. The anterior measurement was the closest distance between the anterior border of the fibula and anterior tibial tubercle. The posterior measurement was the closest distance between the medial border of the fibula and posterior tibial tubercle. In the second method, an angle between the fibular axis and the line connecting the anterior and posterior tibial tubercle was measured. In the third method, the nearest distance between the line perpendicular to the line connecting the tubercles at the anterior tubercle of the distal tibia and the anterior-most margin of the fibula was measured. The fourth method, which was developed in this study, measured the narrowest tibiofibular distance at the joint level. Data were analyzed using Student's t-test and the receiver operating characteristic curve to make comparisons among 4 CT-based parameters. RESULTS: In the comparison between the patients with arthroscopic diastasis and without diastasis, the posterior parameter in the first method and the narrowest tibiofibular distance at the joint level in the fourth method showed a significant difference (P < .05) The areas under the receiver operating characteristic curve (AUCs) of the anterior and posterior parameter of the first method were 0.58 (95% confidence interval [CI], 0.43-0.73; P = .167) of anterior measurement and 0.6 (95% CI, 0.45-0.75; P = .029) of posterior measurement, respectively. The second and third methods presented AUCs of 0.59 (95% CI, 0.44-0.74; P = .458) and 0.48 (95% CI, 0.33-0.64; P = .987), respectively. The fourth method presented an AUC of 0.86 (95% CI, 0.75-0.94; P = .000). When the syndesmosis was measured at the joint level, 2 mm of syndesmosis interval as a cutoff value showed 76% of sensitivity and 81% of specificity. CONCLUSIONS: Syndesmosis assessment using an axial CT scan at the joint level best correlated with the arthroscopic examination. When there is more than 2 mm of widening in syndesmosis on the axial CT scan at the joint level, there is a high likelihood of diastasis of the distal tibiofibular syndesmosis in patients who are suspicious clinically to have acute or chronic syndesmosis lesion. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Management of a 3-year-old with an unstable C6-C7 diastasis without quadriplegia.

BACKGROUND: Caring for pediatric spine trauma patients places spine surgeons in situations that require unique solutions for complex problems. Recent case reports have highlighted a specific injury pattern to the lower cervical spine in very young children that is frequently associated with complete spinal cord injury. METHODS: This report describes the presentation and treatment of a C6-C7 dislocation in a 3-year-old patient with an incomplete spinal cord injury. The highly unstable cervical injury and the need to prevent neurologic decline added complexity to the case. RESULTS: A multi-surgeon team allowed for ample manpower to position the patient; with individuals with the requisite training and experience to safely move a patient with a highly unstable cervical spine. Initial closed reduction under close neurophysiologic monitoring, posterior fusion and immediate anterior stabilization lead to a successful patient outcome with preserved neurologic function. A traumatic cerebrospinal fluid leak, while a concern early on during the procedure, resolved without direct dural repair and did not complicate the patient's fusion healing. Additional anterior stabilization and fusion allowed long-term stability with bone healing that may not be achievable with posterior fixation and/or soft tissue healing alone. CONCLUSIONS: Familiarity with the challenges and solutions presented in the case may be useful to surgeons who could face a similar challenge in the future.