Aims. The ulna is an extremely rare location for primary bone tumours of the elbow in paediatrics. Although several reconstruction options are available, the optimal reconstruction method is still unknown due to the rarity of proximal ulna tumours. In this study, we report the outcomes of osteoarticular ulna allograft for the reconstruction of proximal ulna tumours. Methods. Medical profiles of 13 patients, who between March 2004 and November 2021 underwent osteoarticular ulna allograft reconstruction after the resection of the proximal ulna tumour, were retrospectively reviewed. The outcomes were measured clinically by the assessment of elbow range of motion (ROM), stability, and function, and radiologically by the assessment of allograft-host junction union, recurrence, and joint degeneration. The elbow function was assessed objectively by the Musculoskeletal Tumor Society (MSTS) score and subjectively by the Toronto Extremity Salvage Score (TESS) and Mayo Elbow Performance Score (MEPS) questionnaire. Results. The mean follow-up of patients was 60.3 months (SD 28.5). The mean elbow flexion-extension ROM was 95.8° (SD 21). The mean MSTS of the patients was 84.4 (SD 8.2), the mean TESS was 83.8 (SD 6.7), and the mean MEPS was 79.2 (SD 11.5). All the patients had radiological union at the osteotomy site. Symptomatic osteoarthritic change was observed in three patients (23%), one of whom ended up with elbow joint fusion. Two patients (15.4%) had recurrence during the follow-up period. Surgical complications included two allograft fractures, two plate fractures, three medial instabilities, and two infections. Conclusion. Osteoarticular ulna allograft reconstruction provides acceptable functional outcomes. Despite a high rate of complications, it is still a valuable reconstruction method, particularly in skeletally immature patients who need their distal humerus physis for the rest of hand growth. Cite this article: Bone Jt Open 2024;5(9):749–757

Summary Statement. This 3-dimensional CT study on cadaveric proximal ulna provides further insight into the size and geometry of the proximal ulna intramedullary cavity with potential applications to design and sizing of proximal ulna components. Introduction. Total elbow arthroplasty (TEA) is an established treatment for varying pathologies of the elbow with very good functional outcomes. Optimal fit of ulna components in TEA is predicated on a detailed appreciation of the 3-dimensional anatomy of the proximal ulna intra-medullary cavity, but literature remains scarce. Three-dimensional (3D) models of the proximal ulna have been constructed using computed tomography (CT) programs, accurately defining the angular relations with the cross-sectional extra-medullary dimensions. However, current CT-based thresholding techniques lack accuracy in differentiating cortical from cancellous bone in the metaphyseal region, and thus cannot properly define the intra-medullary region of uncored proximal ulnae. We investigate the geometric dimensions of the proximal ulna intra-medullary cavity using CT studies of cored cadaveric ulnae. Patients & Methods. Three-dimensional models based on CT data of 17 manually cored cadaveric proximal ulnae were created using Matlab program and analyzed. The cadaveric specimens were dissected to identify the medullary canal and coring of the canal of the proximal ulna to exclude the cancellous bone was performed as for ulna canal preparation during TEA. Using the center of a circle fitted over the trochlear ridge as the origin, the diameter, coronal and sagittal angulation of the canal were determined. The diameter, posterior and lateral offsets of the proximal medullary canal were plotted against the normalised axial distance from the origin which was represented in terms of R, the radius of the circle fitted to the trochlear ridge. The normalization of the axial distance was done to compensate for the varying individual ulna lengths. Results. The mean of the radius of the circle which was fitted to the trochlear ridge, R, was found to be 16.64 ± 2.71 mm. The minimum diameter of the canal increased from the origin and peak at 2.3R (just distal to the coronoid process) with a value of 7.08 ± 1.74 mm, decreasing in a linear fashion to 4.48 ± 0.91 mm at 6R. There was an increasing posterior offset which was linear in nature (R. 2. = 0.954) up to 6R (approximately 97mm from the origin). Likewise, the lateral offset increased in a linear fashion (R. 2. = 0.996). Discussion. The findings of our study most likely represent the effective minimum diameter for optimal implant placement, which are consistent with previously documented cadaveric dimensions. The findings also support the current tapered component design of the proximal ulna stemmed implants without the need for significant angulation. Conclusion. Our study provides further insight into the size and geometry of the proximal ulna intramedullary cavity with potential applications to design and sizing of proximal ulna components

Fixation of comminuted olecranon and proximal ulna fractures can be a challenge. The goal of surgery is for stable fixation to encourage union and allow early elbow movement. Over a 3 year period, a low profile titanium, precon-toured olecranon plate (Acumed LLC, Hillsboro, Portland, Oregon) was used in 16 patients with comminuted olecranon and proximal ulna fractures, using a standard universal posterior approach to the olecranon with the patient in a lateral position and active flexion/extension of the elbow was started 48 hours postoperatively. Functional outcomes were measured during follow-up (FU), including range of movement (ROM), Disabilities of the Arm, Shoulder and Hand (DASH) and Mayo Elbow Performance Score (MEPS). There were 9 isolated olecranon fractures, including one open fracture in a multiple injured patient and one an infected non-union and 7 with associated ipsilateral upper limb injuries. Mean age was 52 years (13 to 84) and mean FU was 12.8 months (3 to 33). All had achieved radiological union at 3 months. Overall mean ROM for both groups was 19.3 to 130.7 degrees flexion, 71.8 degrees pronation and 72.1 degrees supination. DASH was 19.1 and MEPS was 87.7. When comparing the 2 groups, there was no significant difference in supination or pronation but all other mean outcomes measurements showed statistical significance in favour of isolated, comminuted olecranon fractures. Extension 9.4 versus 35.0 degrees (p< 0.005), Flexion 140.6 versus 117.5 (p< 0.05), DASH 7.5 versus 34.7 (p=0.0007) and MEPS 96.3 (excellent) versus 78.3 (good) (p< 0.05). There were no infections or failure of metalwork, but two patients had the metalwork removed after union as they required further surgery to their elbows. We demonstrate this is a safe and reliable method of fixation and can expect excellent results when treating isolated comminuted olecranon/proximal ulna fractures and good results when there are associated ipsilateral injuries

Proximal ulnar fractures may be difficult to treat and may result in chronic instability, non-union heterotrophic ossification, synostosis, stiffness and post-traumatic arthritis. The aim of this study is to study success of treatment in achieving stable reduction and early rehabilitation.

Between December 2003 and January 2007 fifty patients (fifty-one elbows) which had sustained 21.A3 and 21.C3 fractures were identified and retrospectively studied.

There were two broad groups of patients. Young males following high energy injuries (average age=38+/−16) and old females with osteoporotic fractures (average age=65+/−17). Twenty-two patients had associated monteggia and seven patients had trans-olacrenon dislocation. Twenty-three patients had radial sided injury. This included two capitelar fractures, nineteen radial head and neck fractures and one radial shaft fracture. Fortyfive patients were treated with plating and two patients were treated with tension band wiring. Five different plating techniques were used to stabilize the fractures.

Eighteen patients had incongruent reduction. Eighteen patients had complications of the treatment. There were seven cases of non-union, one case of loss of fixation, three cases of heterotrophic ossification, three cases of synostosis, one case of deep infection and five complications resulting from radial head fractures.

There was no relationship between loss of fixation and plating techniques. There was a direct relation between comminution and post fixation incongruence. Heterotrophic ossification was associated with comminution, radial head fracture, monteggia fracture-dislocation and non-union. Radio-ulnar synostosis was associated with comminution of the ulnar fracture.

In conclusion, the main predictor of poor outcome is the comminution of proximal ulnar fracture and the ability to achieve congruous fracture fixation.

The purpose of this study was to evaluate the results of custom-made endoprosthetic reconstruction for both tumourous and non-tumourous conditions around the elbow joint. 28 consecutive cases of endoprosthetic elbow reconstruction, performed between 1989 and 2003, were identified using the unit database. There were 12 males and 16 females, with a mean age 48.9 years, (range 14–84). There were 16 cases of malignant tumour (10 primary, 6 secondary), 3 cases of benign tumour (one each of giant cell tumour, osteoblastoma and pigmented villonodular synovitis) and 10 non-oncological cases, (5 cases of fracture, 3 failed total elbow replacements and 1 infected synostosis). A distal humeral prosthesis was used in 16 patients, distal humeral and proximal ulna in 10 patients, proximal ulna with a humeral component in one patient and proximal radial replacement in one patient. Clinical and radiographic review of all available patients, including a functional assessment with The Toronto Extremity Salvage score (TESS) was undertaken. 28 consecutive cases of endoprosthetic elbow reconstruction, performed between 1989 and 2003, were identified using the unit database. There were 12 males and 16 females, with a mean age 48.9 years, (range 14–84). There were 16 cases of malignant tumour (10 primary, 6 secondary), 3 cases of benign tumour (one each of giant cell tumour, osteoblastoma and pigmented villonodular synovitis) and 10 non-oncological cases, (5 cases of fracture, 3 failed total elbow replacements and 1 infected synostosis). A distal humeral prosthesis was used in 16 patients, distal humeral and proximal ulna in 10 patients, proximal ulna with a humeral component in one patient and proximal radial replacement in one patient. Clinical and radiographic review of all available patients, including a functional assessment with The Toronto Extremity Salvage score (TESS) was undertaken. Endoprosthetic reconstruction around the elbow joint is effective in a wide range of pathologies, allowing in most cases a reasonable level of function, even following two-stage revision for infection

Coronoid fractures account for 2 to 15% of the cases with elbow dislocations and usually occur as part of complex injuries. Comminuted fractures and non-unions necessitate coronoid fixation, reconstruction or replacement. The aim of this biomechanical study was to compare the axial stability achieved via an individualized 3D printed prosthesis with curved cemented intramedullary stem to both radial head grafted reconstruction and coronoid fixation with 2 screws. It was hypothesized that the prosthetic replacement will provide superior stability over the grafted reconstruction and screw fixation. Following CT scanning, 18 human cadaveric proximal ulnas were osteotomized at 40% of the coronoid height and randomized to 3 groups (n = 6). The specimens in Group 1 were treated with an individually designed 3D printed stainless steel coronoid prosthesis with curved cemented intramedullary stem, individually designed based on the contralateral coronoid scan. The ulnas in Group 2 were reconstructed with an ipsilateral radial head autograft fixed with two anteroposterior screws, whereas the osteotomized coronoids in Group 3 were fixed in situ with two anteroposterior screws. All specimens were biomechanically tested under ramped quasi-static axial loading to failure at a rate of 10 mm/min. Construct stiffness and failure load were calculated. Statistical analysis was performed at a level of significance set at 0.05. Prosthetic treatment (Group 1) resulted in significantly higher stiffness and failure load compared to both radial head autograft reconstruction (Group 2) and coronoid screw fixation, p ≤ 0.002. Stiffness and failure load did not reveal any significant differences between Group 2 and Group 3, p ≥ 0.846. In cases of coronoid deficiency, replacement of the coronoid process with an anatomically shaped individually designed 3D printed prosthesis with a curved cemented intramedullary stem seems to be an effective method to restore the buttress function of the coronoid under axial loading. This method provides superior stability over both radial head graft reconstruction and coronoid screw fixation, while achieving anatomical articular congruity. Therefore, better load distribution with less stress at the bone-implant interface can be anticipated. In the clinical practice, implementation of this prosthesis type could allow for early patient mobilization with better short- and long-term treatment outcomes and may be beneficial for patients with irreparable comminuted coronoid fractures, severe arthritic changes or non-unions

Purpose: Recognition of the proximal ulna dorsal angulation (PUDA) is important for anatomic reduction of proximal ulnar fractures or osteotomies, especially when using newer straight precontoured proximal ulnar plates. The purpose of this study was to characterize the PUDA in 50 patients with bilateral elbow radiographs. Method: Bilateral elbow radiographs (100 radiographs) were magnified four times using commercial software. The PUDA was measured from the intersection of lines tangent to the subcutaneous border of the olecranon and the proximal ulnar shaft. The olecranon tip-to-apex distance of the PUDA was also measured. Three orthopaedic surgeons independently examined the radiographs and intra/inter-observer reliability was calculated using Intra-Class-Correlation (ICC). Results: A PUDA was present in 96% of radiographs. The average PUDA was 5.7° (range, 0°to14°). The Pearson Correlation coefficient for a side-to-side comparison was 0.86(p< 0.001). The average tip-to-apex distance was 47 mm (34 mm–78mm). No correlation was identified with sex or age. Intra-observer reliability was excellent for the PUDA (ICC 0.892 and 0.863) and good for tip-to-apex distance (ICC 0.762 and 0.827). Inter-observer reliability was good for PUDA (ICC 0.784 and 0.925) and for tip-to-apex distance (ICC 0.711 and 0.769). Conclusion: A mean proximal ulna dorsal angulation of 5.7° is present in 96% of patients at an average of 47 mm distal to the olecranon tip. Measurement of the PUDA has good/excellent inter/intra-observer reliability. Recognition of the PUDA may be helpful in anatomic plating of the ulna. Contralateral PUDA measurements are useful for surgical planning in cases with comminution or distorted anatomy

Anterior elbow dislocations often occur as a fracture-dislocation in which the distal humerus is driven through the olecranon, causing either a simple oblique fracture of the olecranon or a complex, comminuted fracture of the proximal ulna. The purpose of this study was to characterise the morphology and to evaluate the surgical treatment of this injury. Thirteen patients (8 women and 5 men) with a mean age of 42 years were included in this study. Four patients had a simple, oblique fracture of the olecranon and 9 a complex, comminuted fracture of the proximal ulna. Six patients had an associated fracture of the coronoid process which was detached as a large fragment and 7 an additional fracture of the radial head. In all cases the collateral ligaments were found intact. All fractures were treated by open reduction and internal fixation through a midline dorsal approach. Simple fractures of the olecranon were treated with tension-band wiring while comminuted fractures were fixed with a plate and screws. Fractures of the coronoid process were stabilised by interfragmentary screws or small plates. The concomitant radial head fractures were treated by excision of small fragments, internal fixation or radial head replacement. The average follow up was 71 months. According to the functional scale of Broberg and Morrey, the results were excellent in 8 patients, good in 2, and poor in 3. Mild arthritis was observed in one patient. Transolecranon fracture –dislocation of the elbow is often misidentified as an anterior Monteggia lesion or a simple fracture of the olecranon. Differential diagnosis between these lesions is imperative. Consequently, anatomical restoration of the trochlear notch in cases of transolecranon fracture –dislocations can be achieved leading to good long-term results

Purpose. In total elbow arthroplasty (TEA), especially for elbows with condyle defect due to rheumatoid arthritis or trauma, determination of rotation alignment of implants is often difficult. To develop a navigation system for TEA, selecting bony landmarks that can be identified intraoperatively is important. Therefore, we developed a new roentgen free navigation system such as special alignment jigs for TEA based on CT data of normal elbows. The aim of this study was to evaluate alignments of implants after MIS-TEA using the new systems. And also, we reported that 6 bony landmarks on the elbow showed small variability in normal elbows by CT examinations and were considered to be usable as intraoperative landmarks for determining rotational position of implants last year. Especially in RA elbow, posterior aspect of humerus and ulnar aspect of proximal part of ulna were able to be identified even if there is a large bone defect that extends to the lateral or/and medial epicondyle. We used a new roentgen free navigation system in TEA with using Solar elbow from 2009. The aim of this study was to evaluate alignments of implants after MIS-TEA using the new systems by CT examinations. MATERIALS AND METHODS. For determination of alignment and anatomical landmarks to develop the jigs, 3D-CT data of 11 normal elbows was investigated. The posterior aspect of humeral shaft and ulnar aspect of proximal ulna were selected as bony landmarks. Because these can be identified intraoperatively and remain in elbows with extensive bone loss. MIS-TEA with Solar Elbow (Stryker) using these new systems were investigated with postoperative 3D-CT in 14 elbows of 13 patients. Their average age was 68.8 years old. Basic diseases were 10 rheumatoid arthritis and 4 distal humerus injuries. The alignments of humeral and ulnar component were measured on postoperative 3D-CT. RESULTS. Rotational alignment (humerus / ulna) was pronation 6.8° ± 5.7° / pronation 4.6° ± 9.1°; frontal alignment was valgus 0.1° ± 2.7° / valgus 0.1° ± 3.7°; and sagittal alignment was extension 0.6° ± 3.0° / extension 8.9° ± 2.5°. In condyle-defect group (n=5), comparable alignment with condyle-preserved group was obtained. DISCUSSION. The new systems were effective in determining intraoperative alignment even in elbows with extensive bone defect. Extension alignment of the ulna component is because the short component of Solar Elbow was placed along the center axis of the proximal ulna, which inclines in the extension direction relative to the axis of distal ulna

Previous biomechanical studies of lateral collateral ligament (LCL) injuries and their surgical repair, reconstruction and rehabilitation have primarily relied on gravity effects with the arm in the varus position. The application of torsional moments to the forearm manually in the laboratory is not reproducible, hence studies to date likely do not represent forces encountered clinically. The aim of this investigation was to develop a new biomechanical testing model to quantify posterolateral stability of the elbow using an in vitro elbow motion simulator. Six cadaveric upper extremities were mounted in an elbow motion simulator in the varus position. A threaded screw was then inserted on the dorsal aspect of the proximal ulna and a weight hanger was used to suspend 400g, 600g, and 800g of weight from the screw head to allow torsional moments to be applied to the ulna. An LCL injured (LCLI) model was created by sectioning of the common extensor origin, and the LCL. Ulnohumeral rotation was recorded using an electromagnetic tracking system during simulated active and passive elbow flexion with the forearm pronated and supinated. A repeated measures analysis of variance was performed to compare elbow states (intact, LCLI, and LCLI with 400g, 600g, and 800g of weight). During active motion, there was a significant difference between different elbow states (P=.001 pronation, P=.0001 supination). Post hoc analysis showed that the addition of weights did not significantly increase the external rotation (ER) of the ulnohumeral articulation (10°±7°, P=.268 400g, 10.5°±7.1°, P=.156 600g, 11°±7.2°, P=.111 800g) compared to the LCLI state (8.4°±6.4°) with the forearm pronated. However, with the forearm supinated, the addition of 800g of weight significantly increased the ER (9.2°±5.9°, P=.038) compared to the LCLI state (5.9°±5.5°) and the addition of 400g and 600g of weights approached significance (8.2°±5.7°, P=.083 400g, 8.7°±5.9°, P=.054 600g). During passive motion, there was a significant difference between different elbow states (P=.0001 pronation, P=.0001 supination). Post hoc analysis showed that the addition of 600g and 800g but not 400g resulted in a significant increase in ER of the ulnohumeral articulation (9.3°±7.8°, P=.103 400g, 11.2°±6.2°, P=.004 600g, 12.7°±6.8°, P=.006 800g) compared to the LCLI state (3.7°±5.4°) with the forearm pronated. With the forearm supinated, the addition of 400g, 600g, and 800g significantly increased the ER (11.7°±6.7°, P=.031 400g, 13.5°±6.8°, P=.019 600g, 14.9°±6.9°, P=.024 800g) compared to the LCLI state (4.3°±6.6°). This investigation confirms a novel biomechanical testing model for studying PLRI. Moreover, it demonstrates that the application of even small amounts of torsional moment on the forearm with the arm in the varus position exacerbates the rotational instability seen with the LCL deficient elbow. The effect of torsional loading was significantly worse with the forearm supinated and during passive elbow motion. This new model allows for a more provocative testing of elbow stability after LCL repair or reconstruction. Furthermore, this model will allow for smaller sample sizes to be used while still demonstrating clinically significant differences. Future biomechanical studies evaluating LCL injuries and their repair and rehabilitation should consider using this testing protocol

Purpose: The purpose of this study was to evaluate the results of custom-made endoprosthetic reconstruction for both tumourous and non-tumourous conditions around the elbow joint. Methods and Results: 28 consecutive cases of endoprosthetic elbow reconstruction, performed between 1989 and 2003, were identified using the unit database. There were 12 males and 16 females, with a mean age of 48.9 years, (range 14–84). There were 16 cases of malignant tumour (10 primary, 6 secondary), 3 cases of benign tumour (one each of giant cell tumour, osteoblastoma and pigmented villonodular synovitis) and 10 non-oncological cases, (5 cases of fracture, 3 failed total elbow replacements and 1 infected synostosis). A distal humeral prosthesis was used in 16 patients, distal humeral and proximal ulna in 10 patients, proximal ulna with a humeral component in one patient and proximal radial replacement in one patient. Clinical and radiographic review of all available patients, including a functional assessment with The Toronto Extremity Salvage (TES) score was undertaken. The average follow-up was 54.9 months (range 5–144). 5 patients with malignancy died of their disease. One patient required amputation for local recurrence at 5 months. There were two revisions at 4 and 7 years for aseptic loosening of the humeral component. Six patients developed deep prosthetic infection at an average of 21 months (range 6–31), necessitating two-stage revision, of which one patient required subsequent excision arthroplasty. There were no cases of permanent nerve palsy. 18 patients (64.3%) were available for functional follow-up. Average flexion deformity was 33 degrees (7–80) and average flexion was 85 degrees (30–133). The mean TES score was 67.8 (range 36.6–96.6). The mean TES score following two-stage revision for infection, (available in 4/5 patients) was 73.9 (range 54.8–91.6). Conclusion: Custom-made endoprosthetic reconstruction around the elbow joint is effective in a wide range of pathologies, allowing in most cases a reasonable level of function, even following two-stage revision for infection

Aims

To investigate the risk factors for unsuccessful radial head reduction (RHR) in children with chronic Monteggia fractures (CMFs) treated surgically.

Fracture or resection of the radial head can cause unbalance and long-term functional complications in the elbow. Studies have shown that a radial head excision can change elbow kinematics and decrease elbow stability. The radial head is also important in both valgus and varus laxity and displacement. However, the effect of radial head on ulnohumeral joint load is not known. The objective of this experimental study was to compare the axial loading produced at the ulnohumeral joint during active flexion with and without a radial head resection. Ten cadaveric arms were used. Each specimen was prepared and secured in an elbow motion simulator. To simulate active flexion, the tendons of the biceps, brachialis, brachioradialis, and triceps were attached to servo motors. The elbow was moved through a full range of flexion. To quantify loads at the ulnohumeral joint, a load cell was implanted in the proximal ulna. Testing was conducted in the intact then radial head resected case, in supination in the horizontal, vertical, varus and valgus positions. When comparing the average loads during flexion, the axial ulnar load in the horizontal position was 89±29N in an intact state compared to 122±46N during radial head resection. In the vertical position, the intact state produced a 67±16N load while the resected state was 78±23N. In the varus and valgus positions, intact state resulted in loads of 57±26N and 18±3N, respectively. Conversely, with a radial head resection, varus and valus positions measured 56±23N and 54±23N loads, respectively. For both joint configurations, statistical differences were observed for all flexion angles in all arm positions during active flexion (p=0.0001). When comparing arm positions and flexion angle, statistical differences were measured between valgus, horizontal and vertical (p<0.005) except for varus position (p=0.64). Active flexion caused a variation in loads throughout flexion when comparing intact versus radial head resection. The most significant variation in ulnar loading occurred during valgus and horizontal flexion. The vertical and varus position showed little variation because the position of the arm is not affected by the loss of the radial head. However, in valgus position, the resected radial head creates a void in the joint space and, with gravity, causes greater compensatory ulnar loading. In the horizontal position, the forearm is not directly affected by gravitational pull and cannot adjust to counterbalance the resected radial head, therefore loads are localised in the ulnohumeral joint. These findings prove the importance of the radial head and that a radial head resection can overload the ulnohumeral side

Introduction. Hemiarthroplasty is a treatment option for comminuted fractures and non-unions of the distal humerus. Unfortunately, the poor anatomical fit of off-the-shelf distal humeral hemiarthroplasty (DHH) implants can cause altered cartilage contact mechanics. The result is reduced contact area and higher cartilage stresses, thus subsequent cartilage erosion a concern. Previous studies have investigated reverse-engineered DHH implants which reproduce the shape of the distal humerus bone or cartilage at the articulation, but still failed to match native contact mechanics. In this study, design optimization was used to determine the optimal DHH implant shape. We hypothesized that patient-specific optimal implants will outperform population-optimized designs, and both will optimize simple reverse-engineered designs. Methods. The boney geometries of six elbow joints were created based on cadaver arm CT data using a semi-automatic threshold technique in 3D Slicer. CT scans were also obtained with the elbows denuded and disarticulated, such that the high contrast between hydrated cartilage and air could be exploited in order to reconstruct cartilage geometry. Using this 3D model data, finite element contact models were created for each elbow, where bones (distal humerus, proximal ulna and radius) were modelled as rigid surfaces covered by non-uniform thickness layers of cartilage. Cartilage was modelled as a Neo-Hookean hyperelastic material (K = 0.31 MPa, G = 0.37 MPa), and frictionless contact was assumed. In order to simulate hemiarthroplasty, the distal humerus cartilage surface was replaced by either a rigid surface in the shape of the subchondral bone (bone reverse engineered or BRE design), or a surface offset from the bone by some distance, which was defined parametrically and modified by an optimization algorithm. Simple flexion-extension with constant balanced muscle loads was simulated in ABAQUS (Fig 1), and resulting contact areas and contact stresses were calculated. For each specimen, the contact mechanics of the intact and DHH reconstructed joints were calculated. A design optimization algorithm in Matlab was used to determine the optimal offset distance which resulted in contact stress distributions on the ulna and radius which most closely resembled their intact conditions. This procedure was repeated in order to generate specimen-optimal offsets, as well as population-optimal offsets. Results. The population-optimal offset distance was 0.72 mm; whereas the specimen-optimal offsets ranged from 0.52 to 1.04 mm. Compared to the BRE design, which is effectively an offset distance of 0 mm, contact area generally increased at both the ulna (Fig 2) and radius (Fig 3) when either optimized design was used. On average, the specimen-optimal implant designs yielded only slightly larger contact areas than the population-optimal offsets, and only at mid-flexion (40–60 deg). Neither optimization strategy increased contact areas to those of the intact joint. Conclusions. Design optimization is a promising technique for improving patient-specific implants by offering customization in terms of contact mechanics, instead of simply reproducing osseous geometry. In this study, our models predict a large increase in contact area if optimal offsets are used when designing subject-specific DHH, and a population-optimal offset distance seems to be just as good as a subject-optimal offset. For any figures or tables, please contact authors directly (see Info & Metrics tab above).

We report the case of a 12-year-old boy with flexion loss in the left elbow caused by deficient of the concavity corresponding to the coronoid fossa in the distal humerus. The range of motion (ROM) was 15°/100°, and pain was induced by passive terminal flexion. Plain radiographs revealed complete epiphyseal closure, and computed tomography (CT) revealed a flat anterior surface of the distal humerus; the coronoid fossa was absent. Then, the bony morphometric contour was surgically recreated using a navigation system and a three-dimensional elbow joint model. A three-dimensional model of the elbow joint was made preoperatively and the model comprising the distal humerus was milled so that elbow flexion flexion of more than 140° could be achieved against the proximal ulna and radius. Navigation-assisted surgery (contouring arthroplasty) was performed using CT data from this milled three-dimensional model. Subsequently, an intraoperative passive elbow flexion of 135° was obtained. However, active elbow flexion was still inadequate one year after operation, and a triceps lengthening procedure was performed. At the final follow-up one year after triceps lengthening, a considerable improvement in flexion was observed with a ROM of −12°/125°. Plain radiographs revealed no signs of degenerative change, and CT revealed the formation of the radial and coronoid fossae on the anterior surface of the distal humerus. Navigation-assisted surgery for deformity of the distal humerus based on a contoured three-dimensional model is extremely effective as it facilitates evaluation of the bony morphometry of the distal humerus. It is particularly useful as an indicator for milling the actual bone when a model of the mirror image of the unaffected side cannot be applied to the affected side as observed in our case

Purpose. Assess and report the functional and post-operative outcomes of complex acute radial head fractures with elbow instability treated by arthroplasty using an uncemented modular anatomic prosthesis. Methods. Over a 3-year period (2007–2010), 21 patients (mean age 51.9 years) were treated primarily with modular radial head arthroplasty (mean follow up of 27.1 months). Data was collected retrospectively using clinical notes, operation documentation and prospectively using validated scoring systems namely the Oxford Elbow Index, Quick DASH and the Mayo Elbow Performance Score. Associated elbow fractures, ligamentous injury and short to mid term post-operative outcomes including radiographic assessment were recorded. Results. The mean Oxford Elbow Score was 34.80 (range 20–48). The mean Quick Dash score was 26.01 (range 0–68.2). The Mayo Performance score showed 6 scored excellent, 5 scored good, 3 scored fair and 2 scored poor. Regarding post-operative outcomes, 1 patient had a radial head dislocation, 1 patient had prosthesis removal for ongoing pain and 1 patient had a total elbow replacement due to associated proximal ulna fracture non-union. 11 patients had an associated ligamentous injury of which 6 had an associated coronoid fracture. Of note, 7 patient's radiographs showed early signs of implant loosening; this was mainly asymptomatic. Conclusions. With regard to complex radial head fractures with elbow instability, patient outcome measures showed good functionality and overall patient satisfaction despite radiographic evidence of loosening. Post-operative complication rates were low. These findings support the use of this radial head prosthesis in arthoplasty surgery for the treatment of complex acute radial head fractures with elbow instability

Aims

Paediatric fractures are highly prevalent and are most often treated with plaster. The application and removal of plaster is often an anxiety-inducing experience for children. Decreasing the anxiety level may improve the patients’ satisfaction and the quality of healthcare. Virtual reality (VR) has proven to effectively distract children and reduce their anxiety in other clinical settings, and it seems to have a similar effect during plaster treatment. This study aims to further investigate the effect of VR on the anxiety level of children with fractures who undergo plaster removal or replacement in the plaster room.

Purpose of the study: The outcomes of different stabilization methods for unstable forearm fractures are described. Material and methods: From January 1980 through December 2000, 29 patients were treated at the central military hospital orthopedics uint for proximal forearm fractures, 27 underwent surgery. We used the Beaufils classification, depending on the localization of the ulnar fracture. Type 1: metaphyseal fracture (n=12) with dislocation of the radial cup; type 2: epiphyseal fracture with transolecraneal dislocation (n=6); type 3: metaphyso-epiphyseal fracture with anterior dislocation (n=5); type 4: metaphyso-epiphyseal fracture with posterior dislocation (n=5). Results: Outcome was assessed at six months to 20 years follow-up. According to the Morrey classification, outcome was excellent for six patients, good for nine, fair for seven and poor for three. Six patients had a stiff joint, one had a synostosis and three nonunion. Conclusion: To achieve satisfactory outcome, it is crucial to achieve internal fixation of the proximal ulna and reconstruction of the radial length. Resection without replacement of the radial cup is contraindicated in these associated fractures

Introduction: Radial Head Arthroplasty is considered the treatment of choice for unreconstructable radial head fractures. Short-term results in the current literatue are promising. Due to the lack of long-term results, radial head arthroplasty is looked at critically by many surgeons. In our the study we provide the 8.4 years results after treatment with the floating radial head prosthesis by Judet (Tornier, France). Methods: In our department 19 patients were treated with bipolar radial head arthroplasty between 1997 and 2001. 11 prostheses were implantated primary and 6 secondary. The other two were implanted because of a loosening of a prior implanted prosthesis and one after resection of a vast chondrosarcoma. 12 of these patients − 10 men and 2 women – were now examined retrospectively after 101 months (78–132). Results: 6 Patients were treated primary, 5 secondary and one was treated because of a vast chondrosarcoma. There were 5 proximal ulna fractures and 8 processus coronoideus fractures as concomitant injuries of the elbow. Following complications were seen: 2 dislocations, 2 capitellar erosions and 4 cases of heterotopic ossifications. According to the Mayo Elbow Performance Score 4 patients achieved an excellent result, 7 a good, and one a satisfactory result. The mean DASH was 13.7 (0–44). No differences were seen between primary and secondary implantation. The flexion arc was 123° (110–140°), the extension deficit was 20° (0–40°), pronation 61° (30–90°) and supination 62° (40–90°). Conclusion: Our 8.4 years results show that radial head arthroplasty with Judet’s bipolar prosthesis leads to mostly excellent and good – subjective as well as objective – results

Purpose of study: To report the use of a forearm fascial strip to repair the annular ligament and treat late diagnosed or irreducible Monteggia fracture. Methods: Through Boyd’s approach nineteen patients with Monteggia fractures were treated with a technique to reconstruct the annular ligament using forearm fascia, retaining its proximal attachment to the ulna. The radial head was dislocated and the fascial strip wound around the neck of the radius. After reducing the radial head, forearm rotation was checked. The strip was sutured to the residual annular ligament on the proximal ulna after correction of any ulna deformity. In late diagnosis, the ulna deformity was managed with ulna lengthening of approximately 0.5 cm and stabilization with a 4- or 5- hole semi-tubular AO plate. The stability of the radial head was then assessed using intra-operative fluoroscopy. Results: Stability of the radial head was achieved in all cases. According to the Anderson classification, the final outcome was excellent in ten cases satisfactory in eight cases and unsatisfactory in one late diagnosed patient with an associated radioulnar synostosis secondary to a compartment syndrome. There were no failures. Two radiocapitellar K-wires broke while in plaster in the initial period, so the use of a K wire was subsequently abandoned. Conclusions: We have found this technique to be reliable for stabilizing the proximal radioulnar joint. The length of the incision is less than that required for the Bell Tawse (triceps tendon) technique and permits a tourniquet on the upper arm. Poorer results were achieved with delay in diagnosis beyond 6 months. Patients must be warned of potential reduction of forearm rotation