Topographic matching of distal radius and proximal fibula articular surface for distal radius osteoarticular reconstruction

The role of radial head morphology in proximal radioulnar joint congruency during forearm rotation

Purpose

Congruency of the proximal radioulnar joint (PRUJ) is important in the rotation of the forearm while any compromise would significantly impair the elbow function. The purpose of this study is to determine the morphological features of the radial head and investigate its role in the congruency of the PRUJ during forearm rotation. The hypothesis is that the PRUJ is more congruent in the maximal pronation and supination positions than in the neutral position.

Methods

Thirty sets of computed tomography images of the elbow were acquired, and a three-dimensional model of the proximal radius and ulna was generated. The radius of curvature of the radial head and the radial head at the maximal pronation, neutral positions and maximal supination were calculated and compared with a one-way analysis of variance.

Results

The point on the radial head contacting the middle point of radial head at the maximal pronation and supination was located at the ends of the semi-major axis of the ellipse, while it was located at one end of the semi-minor axis at neutral position. The radii of curvature of the pronation, neutral and supination points of the radial head were 14.72 ± 1.51, 9.74 ± 1.49 and 14.58 ± 1.70 mm, respectively. The value of the neutral point was significantly smaller than that of the pronation and supination points.

Conclusions

This study quantitatively evaluated the morphology of the radial head and suggested that the best congruency of the PRUJ was achieved at maximal pronation and supination, while the neutral position was associated with the least congruency.

Level of Evidence

Basic Science Study.

Reconstruction of the distal radius using a double-barrel vascularized fibula flap: a case series

Treatment of distal radius tumor sometimes requires sacrificing the epiphysis. We propose adding to currently available reconstruction options a technique using a double-barrel vascularized fibula flap fixed distally to the first carpal row, conserving midcarpal mobility. We monitored 4 cases of Campanacci III giant-cell tumor and 2 cases of osteosarcoma. After en-bloc tumor resection, a double-barrel vascularized fibula flap was lodged distally in the scaphoid and lunate and proximally in the radius. Follow-up was clinical and radiological, using DASH, PRWE and MSTS functional scores. At a median 3 years' follow-up, there were no cases of recurrence or non-union. Median ranges of motion were 23° flexion, 28° extension, 90° pronation and 62° supination. Median grip strength proportional to the contralateral side was 67%. Median DASH and PRWE functional scores were respectively 13.7 and 17 points. Median MSTS was 83%. Although this technique is challenging, with difficulties in double-barrel flap placement and in pedicle plication, the double-barrel vascularized fibula flap provided a stable and mobile wrist.

Prediction of the Size of the Fragment in Comminuted Coronoid Fracture Using the Contralateral Side: An Analysis of Similarity of Bilateral Ulnar Coronoid Morphology

OBJECTIVE

To evaluate the morphological similarity of bilateral coronoid process.

METHODS

A total of 128 sets of computed tomography images of bilateral coronoid process from patients between January 2015 and December 2016 were acquired for three-dimensional reconstruction to generate a coronoid process model. The patients were aged between 31.4 ± 9.3 years. The upper 40% of the coronoid process was trimmed as targeted fragment for morphological analysis. The height, length, width as well as the radius of the medial and lateral facet of the targeted fragment were compared in terms of laterality, age, and gender. To evaluate the similarity of the articular surface of the coronoid process, a local coordinate was created and coordinate transformation algorithm was developed to realign the bilateral coronoid process for the following matching. Then Delaunay triangulation was introduced for calculation of the area of the articular surface. After matching of articular surface of the upper 40% of bilateral coronoid process, the overlapping area of the articular surface was quantified to assess the similarity in morphology and compared in regard to age and gender.

RESULTS

In this study, the height of the target fragment was 12.40 ± 2.74 mm, which was 12.62 ± 2.06 mm for male patients and 12.13 ± 3.76 mm for female patients (t = 0.94, P = 0.35). The height of the target fragment was 12.79 ± 1.76 mm for patients >40 years and 13.23 ± 3.16 mm for patients <40 years (t = 1.11, P = 0.27). The height of the target fragment of left and right coronoid process was 12.26 ± 3.40 mm and 12.74 ± 2.79 mm (t = 1.15, P = 0.25). The length of the target fragment was 23.81 ± 2.67 mm, which was 23.86 ± 2.11 mm for male patients and 23.76 ± 2.85 mm for female patients (t = 0.23, P = 0.82). The length of the target fragment was 22.92 ± 1.96 mm for patients >40 years and 23.23 ± 2.14 mm for patients <40 years (t = 0.76, P = 0.45). The length of the target fragment of left and right coronoid process was 22.52 ± 2.89 mm and 21.66 ± 3.01 mm, respectively (t = 1.00, P = 0.32). The width of the target fragment was 23.12 ± 1.92 mm on average, which was 23.06 ± 1.54 mm for male patients and 23.19 ± 2.82 mm for female patients (t = 0.33, P = 0.74). The width of the target fragment was 24.82 ± 2.23 mm for patients >40 years and 23.46 ± 3.38 mm for patients <40 years (t = 1.56, P = 0.12). The width of target fragment of left and right coronoid process was 24.42 ± 2.22 mm and 24.47 ± 2.69 mm, respectively (t = 1.31, P = 0.19). The radius of medial facet was 6.44 ± 1.01 mm, which was 6.41 ± 1.39 mm for male patients and 6.47 ± 0.95 mm for female patients (t = 0.28, P = 0.78). The radius of medial facet was 6.82 ± 1.28 mm for patients >40 years and 6.46 ± 0.94 mm for patients <40 years (t = 1.31, P = 0.19). The radius of medial facet of left and right coronoid process was 6.43 ± 1.24 mm and 6.64 ± 1.34 mm (t = 1.60, P = 0.11). The radius of lateral facet was 11.84 ± 3.71 mm, which was 11.61 ± 4.24 mm for male patients and 12.11 ± 3.09 mm for female patients (t = 0.74, P = 0.46). The radius of medial facet was 11.82 ± 3.28 mm for patients >40 years and 12.46 ± 3.94 mm for patients <40 years (t = 1.02, P = 0.31). The radius of lateral facet of left and right coronoid process was 11.97 ± 5.31 mm and 10.29 ± 3.29 mm, respectively (t = 1.70, P = 0.09). The covering percentage of the articular surface of the upper 40% of bilateral coronoid process was 87% ± 12% with the covering percentage as 85.3% ± 14.2% for male patients and 90.0% ± 11.2% for female patients (t = 0.75, P = 0.41). The covering percentage was 88.2% ± 11.7% for patients >40 years and it was 87.4% ± 13.2% for patients <40 years (t = 0.98, P = 0.33).

CONCLUSIONS

The present study suggested that bilateral coronoid process shares high similarity in terms of 3D structure and articular surface morphology, which suggested that the osseous architecture of the coronoid process with comminuted fracture could be predicted by the morphological information of the contralateral side.

Establishment of a True En Face View in the Evaluation of Glenoid Morphology for Treatment of Traumatic Anterior Shoulder Instability

PURPOSE

To develop an accurate and reproducible method for establishment of a true en face view of the glenoid with a traumatic bone defect.

METHODS

A total of 50 sets of computed tomography images of the glenoid were used for 3-dimensional reconstruction. Both a quantitative definition and a practical method were designed for creation of the true en face view of the glenoid with a traumatic bone defect. The accuracy and reliability of the quantitative definition and the practical method were evaluated by calculating the maximal projection area and the simulated bone defect size.

RESULTS

The glenoid surface could be fit with a sphere with a radius of 26.11 ± 2.15 mm (P < .001, R² = 0.98). The true en face view could be established with the quantitative definition, which resulted in the maximal projection area, whereas any tilt would lead to decreased values (P < .05). To establish the true en face view on the glenoid with a traumatic bone defect, a vector from the center of the best-fit sphere of the glenoid surface to the middle point of an arc connecting the supraglenoid and infraglenoid tubercles was generated, which served as a perpendicular for glenoid reorientation. Cases off the true en face view would result in less accurate estimation of the bone defect size (P < .05).

CONCLUSIONS

This study provided a quantitative definition and a practical method for generation of the true en face view in the presence of a traumatic bone defect based on the best-fit sphere of the glenoid surface as well as the anatomic landmark of the supraglenoid and infraglenoid tubercles. This study may improve the reliability of the quantification of traumatic bone defects of the glenoid.

CLINICAL RELEVANCE

The practical method for establishment of the true en face view of the glenoid would be useful in decision making for the treatment of traumatic anterior shoulder instability.

Functional results of wrist arthrodesis versus arthroplasty with proximal fibula following giant cell tumour excision of the distal radius

Twenty-one patients underwent excision of a Campanacci grade III giant cell tumour of the distal radius and had reconstruction using a proximal fibula autograft. We compared the functional results of wrist arthrodesis versus arthroplasty. All 21 patients healed in an average of 8 months, and all have remained disease free. The Musculoskeletal Tumor Society 93, the Disabilities of the Arm, Shoulder, and Hand scores and the grip strength of the operated wrist compared with the contralateral wrist were 93%, 7, and 71% for the arthrodesis group and 83%, 17, and 40% for the arthroplasty group. Arthrodesis of the reconstructed radiocarpal joint provided better grip strength and functional outcomes than arthroplasty. Level of evidence: III.