Similar Regional Hypertrophy of the Elbow Flexor Muscles in Response to Low-Load Training With Vascular Occlusion at Short Versus Long Muscle Lengths.

BACKGROUND: The regional hypertrophy response of elbow flexor muscles was compared after unilateral elbow flexion training in extended versus flexed shoulder position under vascular occlusion, which can induce muscle hypertrophy in the absence of muscle damage-induced edema/swelling. HYPOTHESIS: Hypertrophy of elbow flexor muscles would be greater in extended compared with flexed shoulder position. STUDY DESIGN: Randomized within-subject trial. LEVEL OF EVIDENCE: Level 2. METHODS: A total of 21 resistance-trained men (age, 25 ± 5 years; height, 1.78 ± 0.07 m; weight, 79.3 ± 13.1 kg) performed unilateral elbow flexions with one shoulder extended/elbow flexor muscles lengthened/long muscle length (LONG) and the other flexed/elbow flexor muscles shortened/short muscle length (SHORT) under a low-load (30% 1-repetition maximum) vascular occlusion training regimen (15 repetitions per set, 4 sets per session, 4 sessions per week for 3 weeks, using 80% of vascular occlusion pressure). Magnetic resonance imaging measured elbow flexor muscles cross-sectional area (EFCSA) pre- and post-training at 45%, 65%, and 85% of humerus length. RESULTS: EFCSA significantly increased in both SHORT (P = 0.04) and LONG (P = 0.05) at 45% and 85% lengths (P < 0.01 for both). Changes in EFCSA between SHORT and LONG were statistically similar at the 45% (+6.20% vs +5.08%; Cohen d = 0.006; P = 0.98), 65% (+5.91% vs +3.83%, Cohen d = 0.28, P = 0.30), and 85% lengths (+8.51% vs +7.38%, Cohen d = 0.18,P = 0.56). CONCLUSION: Muscle hypertrophy of the elbow flexor muscles displayed a similar behavior after low-load elbow flexion training with vascular occlusion performed in the extended versus flexed shoulder position. CLINICAL RELEVANCE: Therapists, clinicians, and coaches may choose elbow flexion exercises expecting to achieve similar results for hypertrophy in this muscle group, such that exercise selection may rely on availability of equipment in the training room or personal preference.

Study on morphometry of distal humerus and its clinical correlations.

Morphometric analysis of bones gives essential information for reconstructive surgeries and prosthetics. It is also useful in forensic medicine to identify and estimate age, sex and height from skeletal remains. We have measured and analyzed the following parameters in 100 distal humerii: the maximal length of the humerus, transverse distance between medial epicondyle and lateral epicondyle, horizontal diameter of trochlea, antero-posterior diameter of trochlea, and horizontal distance from medial epicondyle to capitulum. Distal humeral fractures are often challenging and difficult to treat which requires knowledge of distal humeral anatomy. Data from this study and the comparisons made will help in this.

Mini-fragment Plate Fixation after Olecranon Osteotomy for Distal Humerus Fractures.

PURPOSE: While olecranon osteotomies are helpful for distal humerus visualization, traditional methods of fixation are commonly irritating for patients and require hardware removal. Recent studies have shown lower hardware removal rates for medullary screw constructs and 3.5-mm plates, but no studies have investigated the use of 2.7-mm plates for olecranon osteotomy fixation. The purpose of this study is to report on the outcomes of single 2.7-mm mini-fragment plate fixation of olecranon osteotomies for distal humerus intra-articular fractures. METHODS: Patients who sustained an intra-articular distal humerus fracture, as identified by CPT codes, were reviewed retrospectively over a 5-year study period (2016-2020) at a single Level I trauma center after IRB approval. Only patients who underwent an olecranon osteotomy for distal humerus visualization during their definitive operation and that was subsequently fixed with a single 2.7-mm plate were included. Primary outcomes were implant removal and osteotomy union. Secondary outcomes included indications for implant removal, implant failure, infection, and revision surgery. Hardware removal rates were compared to historically reported rates in the literature. χ2 versus Fisher's exact tests were used to compare fixation groups based on number of patients in each cohort (5 or less was used for the cut-off for Fisher's exact test). RESULTS: 38 patients were included in the final analysis. The average age was 50 years (standard deviation [SD] 18), 58% (22 patients) were female, and there was an average follow-up time of 9.7 months (SD 5). All patients with mini-fragment plate fixation went on to union of their olecranon osteotomy. Three (7.8%) patients had their olecranon hardware removed for all causes: one for revision open reduction and internal fixation (ORIF), one for irritation, and one removal during concomitant capsulectomy and manipulation. There was a 21% (8 patients) revision surgery rate in the cohort but only 3 of those were for issues related to the olecranon osteotomy. One patient required revision ORIF of the olecranon osteotomy for hardware loosening. Compared to other fixation constructs, mini-fragment plates had a lower removal rate than tension band wiring (P = 0.0002) and 3.5-mm plates (P = 0.05) and similar among medullary screws ± wires. Nonunion rates were similar between all constructs (P = 0.07). CONCLUSION: Single 2.7-mm mini-fragment plate fixation of olecranon osteotomies for distal humerus fractures is safe and effective with low rates of revision, hardware removal, and nonunion. This type of fixation should be considered when treating intra-articular distal humerus fractures that require an olecranon osteotomy.

Randomized study for a novel elbow joint fixation device on postoperative complications in patients undergoing percutaneous coronary diagnostic or therapeutic procedures through the brachial artery.

Brachial artery access for coronary diagnostic or therapeutic procedures is associated with a greater risk of vascular complications. To determine whether 3D printing of a novel elbow joint fixation device could reduce postoperative complications after percutaneous coronary diagnostic or therapeutic procedures through the brachial artery. Patients who underwent percutaneous coronary diagnostic or therapeutic procedures by brachial access were randomly assigned to receive either a 3D-printed elbow joint fixation device (brace group) or traditional compression (control group) from March 2023 to December 2023. The severity of puncture site-related discomfort at 24 h postsurgery was significantly lower in the brace group (P = 0.014). Similarly, the upper arm calibration rate at 24 h postsurgery was significantly lower in the brace group [0.024 (0.019-0.046) vs. 0.077 (0.038-0.103), P < 0.001], as was the forearm calibration rate [0.026 (0.024-0.049) vs. 0.050 (0.023-0.091), P = 0.007]. The brace group had a significantly lower area of subcutaneous hemorrhage at 24 h postsurgery [0.255 (0-1.00) vs. 1 (0.25-1.75) cm2]. In patients who underwent percutaneous coronary diagnostic or therapeutic procedures by brachial access after manual compression hemostasis, the novel elbow joint fixation device was effective at reducing puncture site-related discomfort, alleviating the degree of swelling, and minimizing the subcutaneous bleeding area. Additionally, no significant complications were observed.Trial registration: China Clinical Trial Registration on 01/03/2023 (ChiCTR2300068791).

Clinical study on improving the diagnostic accuracy of adult elbow joint cartilage injury by multisequence magnetic resonance imaging.

BACKGROUND: Due to frequent and high-risk sports activities, the elbow joint is susceptible to injury, especially to cartilage tissue, which can cause pain, limited movement and even loss of joint function. AIM: To evaluate magnetic resonance imaging (MRI) multisequence imaging for improving the diagnostic accuracy of adult elbow cartilage injury. METHODS: A total of 60 patients diagnosed with elbow cartilage injury in our hospital from January 2020 to December 2021 were enrolled in this retrospective study. We analyzed the accuracy of conventional MRI sequences (T1-weighted imaging, T2-weighted imaging, proton density weighted imaging, and T2 star weighted image) and Three-Dimensional Coronary Imaging by Spiral Scanning (3D-CISS) in the diagnosis of elbow cartilage injury. Arthroscopy was used as the gold standard to evaluate the diagnostic effect of single and combination sequences in different injury degrees and the consistency with arthroscopy. RESULTS: The diagnostic accuracy of 3D-CISS sequence was 89.34% ± 4.98%, the sensitivity was 90%, and the specificity was 88.33%, which showed the best performance among all sequences (P < 0.05). The combined application of the whole sequence had the highest accuracy in all sequence combinations, the accuracy of mild injury was 91.30%, the accuracy of moderate injury was 96.15%, and the accuracy of severe injury was 93.33% (P < 0.05). Compared with arthroscopy, the combination of all MRI sequences had the highest consistency of 91.67%, and the kappa value reached 0.890 (P < 0.001). CONCLUSION: Combination of 3D-CISS and each sequence had significant advantages in improving MRI diagnostic accuracy of elbow cartilage injuries in adults. Multisequence MRI is recommended to ensure the best diagnosis and treatment.

[Radial neck fracture in children-"A benign fracture?"] / Die Radiushalsfraktur im Kindesalter ­ "eine gutartige Fraktur"?

Radial neck fractures in children are rare but clinically relevant injuries that are often accompanied by concomitant injuries. Girls between the ages of 8 and 12 years old are more frequently affected, whereby a cubitus valgus variant can be a predisposing factor. The main trauma mechanism is a fall onto the outstretched, supinated arm with additional valgus stress. Radial neck fractures can be associated with concomitant injuries of the elbow joint, including an olecranon fracture and elbow dislocation. The diagnosis is typically made by conventional X­radiographs, although ultrasonography can be indicated in younger children.The treatment depends on the fracture dislocation. Conservative treatment is certainly possible at any age if the proximal fragment is angulated less than 20°, while a surgical intervention can be indicated for larger dislocations depending on age. Closed reduction with internal fixation using a elastic stable intramedullary nail (ESIN) according to Métaizeau has become established as the standard procedure. Complications such as premature epiphyseal joint closure, synostosis, avascular necrosis, pseudarthrosis and deformation of the radial head can occur and affect the functional outcome. The treatment of such complications often requires a comprehensive multidisciplinary approach and can include both conservative and surgical measures. Long-term studies show that most patients with radial neck fractures achieve good to very good outcomes, although certain predictive factors are associated with poorer outcomes.Knowledge of the potential complications and their treatment is crucial for the successful management of children with radial neck fractures and should be considered when making clinical decisions.

Quality control of elbow joint radiography using a YOLOv8-based artificial intelligence technology.

BACKGROUND: To explore an artificial intelligence (AI) technology employing YOLOv8 for quality control (QC) on elbow joint radiographs. METHODS: From January 2022 to August 2023, 2643 consecutive elbow radiographs were collected and randomly assigned to the training, validation, and test sets in a 6:2:2 ratio. We proposed the anteroposterior (AP) and lateral (LAT) models to identify target detection boxes and key points on elbow radiographs using YOLOv8. These identifications were transformed into five quality standards: (1) AP elbow positioning coordinates (XA and YA); (2) olecranon fossa positioning distance parameters (S17 and S27); (3) key points of joint space (Y3, Y4, Y5 and Y6); (4) LAT elbow positioning coordinates (X2 and Y2); and (5) flexion angle. Models were trained and validated using 2,120 radiographs. A test set of 523 radiographs was used for assessing the agreement between AI and physician and to evaluate clinical efficiency of models. RESULTS: The AP and LAT models demonstrated high precision, recall, and mean average precision for identifying boxes and points. AI and physicians showed high intraclass correlation coefficient (ICC) in evaluating: AP coordinates XA (0.987) and YA (0.991); olecranon fossa parameters S17 (0.964) and S27 (0.951); key points Y3 (0.998), Y4 (0.997), Y5 (0.998) and Y6 (0.959); LAT coordinates X2 (0.994) and Y2 (0.986); and flexion angle (0.865). Compared to manual methods, using AI, QC time was reduced by 43% for AP images and 45% for LAT images (p < 0.001). CONCLUSION: YOLOv8-based AI technology is feasible for QC of elbow radiography with high performance. RELEVANCE STATEMENT: This study proposed and validated a YOLOv8-based AI model for automated quality control in elbow radiography, obtaining high efficiency in clinical settings. KEY POINTS: QC of elbow joint radiography is important for detecting diseases. Models based on YOLOv8 are proposed and perform well in image QC. Models offer objective and efficient solutions for QC in elbow joint radiographs.

Capsule release surgery temporarily reduces contracture in a rat elbow model of arthrofibrosis.

Elbow trauma can lead to joint contracture and reduced range of motion (ROM). Nonsurgical interventions can improve ROM, but in some cases capsule release surgery is required. Although surgery can improve ROM, it often does not restore full ROM. Thus, alternatives are needed. One approach is to target activated myofibroblasts, which are commonly associated with fibrotic tissue. Mechanical and biochemical cues drive a feedback loop that can result in normal or pathological healing. We hypothesize that this feedback loop exists in joint contracture and can be manipulated so that myofibroblast activity is reduced, normal healing is achieved, and ROM is improved. We previously demonstrated that blebbistatin can inhibit myofibroblast contractile forces and reduce collagen synthesis in vitro. Thus, the purpose of this study was to assess the use of blebbistatin in an animal model of elbow contracture, which was induced in 7 groups of 4 rats each (n = 28). All elbows were mechanically and histologically tested. The uninjured contralateral elbows of each rat were used as a control group. Capsule release surgery significantly improved (p < 0.01) outcomes 1 week after surgery compared to injury alone and was not significantly different from uninjured elbows. Three weeks after surgery, outcomes worsened, indicating joint stiffening consistent with what is observed clinically. The addition of blebbistatin did not significantly improve outcomes. Future work will investigate relationships among treatment, fibrotic tissue deposition, myofibroblast activity, and biomechanics to determine if blebbistatin is a useful adjunctive therapy for treating joint contracture.

Chronic Bilateral Olecranon Bursitis: A Case Report.

Olecranon bursitis is a common condition that primarily affects men between the ages of 30 and 60. Although the conservative treatment of acutely inflamed olecranon bursitis is relatively straightforward, managing chronic olecranon bursitis can be challenging. In this publication, we report a case of rare bilateral chronic olecranon bursitis and discuss the rationale for choosing the best treatment option.

Clinical outcomes of triceps reflecting anconeus pedicle and olecranon osteotomy approach for distal humerus intercondylar fractures.

BACKGROUND: The preferred treatment for distal humeral intercondylar fractures is open reduction and internal fixation. While there is consensus about the posterior approach, several posterior approaches have been developed. It is debatable as to which approach is best. AIM: To compare triceps reflecting anconeus pedicle (TRAP) and olecranon osteotomy approaches for internal fixation of distal humeral intercondylar fracture. METHODS: In total, 40 cases of Arbeitsgemeinschaft für Osteosynthesefragen/Association of the Study of Internal Fixation type C, closed, and Gustilo type I intercondylar humeral fractures were included. Patients ranged in age from 18 years to 70 years. The patients were randomized into two groups: TRAP group and olecranon osteotomy group, with 20 cases in each. All were followed up at 6 wk, 3 months, 6 months, and 12 months. Functional outcomes were measured in terms of flexion-extension arc, Disabilities of Arm, Shoulder and Hand score, and Mayo Elbow Performance Score. RESULTS: The mean age was 43.2 years in the TRAP group and 37.5 years in the olecranon osteotomy group. The mean operative time and mean duration of hospital stay in the TRAP group were significantly higher than in the olecranon osteotomy group (119.5 vs 111.5 min and 9.85 vs 5.45 d, respectively). The mean arc of flexion-extension, Disabilities of Arm, Shoulder and Hand score, and Mayo Elbow Performance Score were comparable without any significant difference in the groups at the 12-month follow-up (107.0 vs 106.2, 18.3 vs 15.7, and 84.2 vs 86.2, respectively). Ulnar paresthesia and superficial infections were comparable in both groups (2 cases vs 3 cases and 3 cases vs 2 cases, respectively). Hardware prominence was significantly higher in the olecranon osteotomy group, mostly due to tension band wiring. CONCLUSION: Both approaches were equivalent, but there is a need for further study including higher numbers of subjects and longer study duration to prove the benefits of one approach over the other.

[Bone-cartilage transfer for osteochondritis dissecans of the humeral capitellum]. / Knorpel-Knochen-Transfer bei Osteochondrosis dissecans des Capitulum humeri.

OBJECTIVE: Treatment of focal cartilage defects of the humeral capitellum with autologous bone-cartilage cylinders to prevent development of arthritis of the elbow joint. INDICATIONS: High-grade, unstable lesions (> 50% of the capitellum, grade III-IV according to Dipaola), including those involving the lateral edge of the capitellum and with a depth of up to 15 mm. CONTRAINDICATIONS: Stable lesions and generalized osteochondritis of the capitellum (including Panner's disease), as well as a relative contraindication for lesions > 10 mm, as the largest punch has a maximum diameter of 10 mm. SURGICAL TECHNIQUE: Arthroscopy of the elbow joint, transition to open surgery. First, the size of the cartilage defect in the capitellum is determined. Then, one (or several) osteochondral cylinders (OATS Arthex) are removed, which as far as possible completely encompass the defect zone. Corresponding intact bone-cartilage cylinders are obtained from the ipsilateral proximal lateral femoral condyle, each with a 0.3 mm larger diameter via an additive miniarthrotomy. The "healthy" cylinders are then inserted into the defect zone in a "press fit" technique. POSTOPERATIVE MANAGEMENT: An upper arm cast in neutral position of the hand for 10-14 days, simultaneously beginning physiotherapy (active-assisted movements) and lymphatic drainage. As soon as painless range of motion (ROM) is restored (goal: by week 6), isometric training can be started. Resistance training starts from week 12. Competitive sports are only recommended after 6(-8) months. RESULTS: The current state of research on the surgical treatment of OCD of the humeral capitellum using autologous osteochondral grafts shows mostly promising results. A recent meta-analysis of 24 studies reports a significantly higher (p < 0.01) rate of return to sports (94%) compared to fragment fixation (64%) or microfracture and debridement (71%) [41]. However, the increased donor-site morbidity must be taken into account (ca. 7.8%).

[Technical modifications to elbow interposition arthroplasty]. / Technische Modifikation der Interpositionsarthroplastik des Ellenbogens.

OBJECTIVE: Interposition arthroplasty of the elbow involves the interposition of a fascia lata or dermis autograft or allograft between the distal humerus and the ulna or radius, while preserving the original form of articulation. INDICATIONS: Interposition arthroplasty is indicated for young patients with high functional demands who suffer from end-stage elbow arthritis and associated pain or joint stiffness. CONTRAINDICATIONS: Contraindications include acute or subacute infection, skeletal immaturity, bone loss, deformity, or gross instability. SURGICAL TECHNIQUE: Once the ulnar nerve has been secured, joint access is established via a posterior approach. The radial collateral ligament (RCL) and the common extensor tendon origin (CEO) are detached, while preserving the anconeus muscle and the lateral ulnar collateral ligament (LUCL). Subsequently, a capsular release is required to maintain adequate joint exposure and address the accompanying stiffness. Three to four transosseous drill holes are placed at the level of the distal humerus to secure the graft. After the graft has been positioned successfully within the joint space using two guide sutures, it can be secured to the distal humerus using a horizontal mattress stitch. Finally, the detached tendon and ligament structures are reconstructed. POSTOPERATIVE MANAGEMENT: After initial immobilization, early functional exercise of the elbow is performed in the motion orthosis, avoiding valgus or varus stress. RESULTS: The efficacy of elbow interposition arthroplasty has been demonstrated, particularly for young and active patients with severe inflammatory or post-traumatic osteoarthritis. Despite the results in terms of postoperative function and pain reduction are satisfactory, the current literature reports high complication, subsequent treatment, and revision rates. In the event of interposition arthroplasty failure, revision with another interposition procedure or conversion to endoprosthesis may be considered.

Management of Synovial Chondromatosis of the Elbow With Ulnar Nerve Palsy by Open Approach: A Case Report.

Synovial chondromatosis is a rare condition characterized by benign metaplasia of the synovial membrane, leading to nodular growths within the joint space. We present the case of a 58-year-old woman with persistent pain and stiffness in her right elbow, ultimately diagnosed with synovial chondromatosis. Examination revealed joint effusion, tenderness, and restricted range of motion, with palpable loose bodies and ulnar nerve symptomatology. X-ray confirmed the diagnosis. Open synovectomy was performed, with meticulous attention to ulnar nerve protection and decompression. Postoperative care included analgesics, anti-inflammatories, and physiotherapy. Synovial chondromatosis of the elbow requires prompt diagnosis and surgical intervention to alleviate symptoms and prevent complications. Prognosis is favorable with complete removal of the affected tissue. Ulnar nerve palsy should be carefully addressed during surgical management.

Assessment of a New Elbow Joint Positioning Method Using Area Detector Computed Tomography.

We propose a sitting position that achieves both high image quality and a reduced radiation dose in elbow joint imaging by area detector computed tomography (ADCT), and we compared it with the 'superman' and supine positions. The volumetric CT dose index (CTDIvol) for the sitting, superman, and supine positions were 2.7, 8.0, and 20.0 mGy and the dose length products (DLPs) were 43.4, 204.7, and 584.8 mGy • cm, respectively. In the task-based transfer function (TTF), the highest value was obtained for the sitting position in both bone and soft tissue images. The noise power spectrum (NPS) of bone images showed that the superman position had the lowest value up to approx. 1.1 cycles/mm or lower, whereas the sitting position had the lowest value when the NPS was greater than approx. 1.1 cycles/mm. The overall image quality in an observer study resulted in the following median Likert scores for Readers 1 and 2: 5.0 and 5.0 for the sitting position, 4.0 and 3.5 for the superman position, and 4.0 and 2.0 for the supine position. These results indicate that our proposed sitting position with ADCT of the elbow joint can provide superior image quality and allow lower radiation doses compared to the superman and supine positions.

Thoracic outlet syndrome in overhead athletes.

Background: We aimed to retrospectively compare the clinical outcomes of endoscopy-assisted first-rib resection for thoracic outlet syndrome (TOS) between overhead athletes and nonathletes and investigate the return to same-level sports rate in overhead athletes. Methods: We retrospectively reviewed 181 cases with TOS (75 women, 106 men; mean age, 28.4 years; range, 12-57 years) who underwent endoscopy-assisted first-rib resection. We divided into two groups: 79 overhead athletes and 102 nonathletes groups. A transaxillary approach for first-rib resection and neurovascular decompression was performed under magnified visualization. Endoscopic findings related to the neurovascular bundle, interscalene distance, and scalene muscle were evaluated intraoperatively. We assessed the Roos and Disability of the Arm, Shoulder, and Hand scores, return to same-level sports rate, and ball velocity. Results: Overhead athletes were significantly more likely to be men, younger, used the dominant side more frequently, and have a larger physique, more shoulder and elbow pain, and shorter symptom duration. The outcomes of the Roos score revealed significant differences in excellent or good results between overhead athletes (91.1%) and nonathletes (62.8%). The two groups significantly differed in preoperative and postoperative Disability of the Arm, Shoulder, and Hand and recovery rate scores (P = .007, < .001, < .001). Conclusion: Overhead athletes with TOS were more likely to be men, younger, dominant side more frequently, and have more shoulder and elbow pain, and a shorter symptom duration. Endoscopy-assisted transaxillary first-rib resection and neurolysis provided superior clinical outcomes in overhead athletes with TOS compared with nonathletes and a high return-to-same-level-play rate in sports.

Tuberculosis of the Elbow Joint in an Indian Boy: A Rare Entity With a Diagnostic Challenge.

Tuberculosis of the bones and joints is an infrequently reported entity. Isolated involvement of the elbow joint is exceedingly rare, even in endemic countries. The diagnosis is an arduous task, especially if it presents in younger age groups. Herein, a case of tuberculosis of the right elbow joint in a seven-year-old Indian child is presented. The diagnosis was challenging due to the vague clinical features and rarity of the disease, but he was diagnosed after a detailed clinical examination along with a radiometric assessment. He was initiated on the appropriate chemotherapy.

Outcomes of complete neurotomy and immediate repair of the musculocutaneous nerve for treatment of elbow spasticity.

Neurotomy interrupts the stretch reflex and can be used for the treatment of spasticity. We hypothesized that neurotomy with nerve repair reduces spasticity while preserving motor function due to the preferential recovery of efferent over afferent fibres. This study reports the 1-year outcomes of neurotomy and immediate repair of the musculocutaneous nerve in the proximal arm for treatment of elbow flexor spasticity, comparing these to outcomes in the literature for neurectomy without nerve repair. A total of 10 adult patients with spasticity of the elbow flexors from stroke or traumatic brain injury who had undergone neurotomy and immediate repair of the musculocutaneous nerve were prospectively studied. The results suggest that this procedure effectively reduces elbow flexor spasticity, improves elbow resting position, active elbow extension and is useful for achieving patient goals with effects lasting at least 12 months.Level of evidence: IV (therapeutic).

Long-terms outcomes of radial head arthroplasty using a bipolar prosthesis.

BACKGROUND: In acute treatment of radial head fractures, a radial head prosthesis can be considered if open reduction and internal fixation are not technically feasible. METHODS: We reviewed the data of 27 consecutive bipolar Judet radial head prostheses implanted in patients with unreconstructable radial head fractures and no other concomitant fractures (coronoid or olecranon factures). The lesions of the lateral collateral ligament were rated according to the McKee classification. Twenty-three patients with more than ten-year follow-up participated in this retrospective study All patients underwent assessments for pain, range of motion and stability using the Mayo Elbow Performance Score, the QuickDash questionnaire and a Visual Analogue Scale for pain. Radiography assessment was performed to determine the correct setting of the implant, presence of periprosthetic loosening, prosthetic disassembly, heterotopic ossification, capitellum and ulnohumeral degenerative changes. RESULTS: Mean follow-up was 149 months (± 12.2). Mean range of motion in flexion-extension was 111° (± 10.55), mean extension was 18° (± 14.32) and mean flexion was 130° (± 11.4). Mean arc of motion in supination-pronation was 150° (± 12.26). The mean Mayo Elbow Performance Score was 88, the mean QuickDash score was 7.3; 86% of the patients were satisfied. Seven patients (26%) required secondary surgery. The most frequent complication was heterotopic ossification, which had negative consequences on the functional result. CONCLUSIONS: Bipolar radial head prostheses are an option for acute treatment of isolated unreconstructable radial head fractures. During follow-up, three patients required implant revision and removal; the capitellum surface presented severe degenerative changes and the prosthesis was not replaced. Another complication was the risk of implant dislocation, in relation to implant design, incorrect positioning of the radial head stem or else to inadequate reconstruction of the lateral collateral ligament. Further work is needed to establish the long-term follow-up results of Judet implants in complex elbow fractures.

Digital smart internal fixation surgery for coronal process basal fracture with normal joint spaces or radius-shortening: Occult factor of radius-ulna load sharing.

BACKGROUND: Reasonable postoperative humeroradial and humeroulnar joint spaces maybe an important indicator in biomechanical stability of smart internal fixation surgery for coronoid process basal fractures (CPBF). The aim of this study is to compare elbow articular stresses and elbow-forearm stability under smart internal fixations for the CPBF between normal elbow joint spaces and radius-shortening, and to determine the occult factor of radius-ulna load sharing. METHODS: CT images of 70 volunteers with intact elbow joints were retrospectively collected for accurate three-dimensional reconstruction to measure the longitudinal and transverse joint spaces. Two groups of ten finite element (FE) models were established prospectively between normal joint space and radius-shortening with 2.0 mm, including intact elbow joint and forearm, elbow-forearm with CPBF trauma, anterior or posterior double screws-cancellous bone fixation, mini-plate-cancellous bone fixation. Three sets of physiological loads (compression, valgus, varus) were used for FE intelligent calculation, FE model verification, and biomechanical and motion analysis. RESULTS: The stress distribution between coronoid process and radial head, compression displacements and valgus angles of elbow-forearm in the three smart fixation models of the normal joint spaces were close to those of corresponding intact elbow model, but were significantly different from those of preoperative CPBF models and fixed radius-shortening models. The maximum stresses of three smart fixation instrument models of normal joint spaces were significantly smaller than those of the corresponding fixed radius-shortening models. CONCLUSIONS: On the basis of the existing trauma of the elbow-forearm system in clinical practice, which is a dominant factor affecting radius-ulna load sharing, the elbow joint longitudinal space has been found to be the occult factor affecting radius-ulna load sharing. The stability and load sharing of radius and ulna after three kinds of smart fixations of the CPBF is not only related to the anatomical and biomechanical stability principles of smart internal fixations, but also closely related to postoperative elbow joint longitudinal space.