The proximal vastus lateralis flap: An anatomical and radiological study.

INTRODUCTION: Soft-tissue reconstruction following acetabular or proximal femur resection for bone tumors is challenging. The vastus lateralis flap has been proposed as an advancement or rotational flap to cover soft-tissue defects for such locoregional indications. We performed an anatomical and a radiological study to assess the vascularization of the proximal vastus lateralis muscle achieved through the transverse branch of the lateral circumflex femoral artery in order to decrease the morbidity of the classical flap retrieval technique. MATERIAL AND METHODS: Five fresh adult cadavers were dissected bilaterally. Each vastus lateralis dissection was prealably injected with contrast-media agent through the lateral circumflex artery and CT scan images was recorded. A descriptive and an analytical study were carried out. RESULTS: The median length and width of the entire muscle were 31.2cm (Q1-Q3: 29.7-33.3) and 12.7cm (Q1-Q3: 7.0-14.9), respectively; the median surface area of the entire vastus lateralis muscle was 282cm2 (Q1-Q3: 172.6-455.6) cm2. The median length and width of the perfused area were 13.3cm (Q1-Q3: 12.3-16.6) and 9.4cm (Q1-Q3: 6.9-8.8) cm, respectively; the median surface of the perfused area was 89.4cm2 (Q1-Q3: 67.4-110.5) cm2. The mean length of the pedicle measured on the CT scan was 6.3cm (95% CI: 5.5-7.1). CONCLUSION: The proximal vastus lateralis flap as a pedicled muscular flap supplied by the transverse branch of the lateral circumflex femoral artery is a muscular flap that can be used by reconstructive and orthopaedic surgeons to repair soft-tissue defects around the hip joint without undue damage to the functional apparatus of the knee.

Anatomy of the median nerve and its clinical applications.

The median nerve is a mixed sensory and motor nerve. It is classically described as the nerve of pronation, of thumb, index finger, middle finger and wrist flexion, of thumb antepulsion and opposition, as well as the nerve of sensation for the palmar aspect of the first three fingers. It takes its name from its middle position at the end of the brachial plexus and the forearm. During its course from its origin at the brachial plexus to its terminal branches, it runs through various narrow passages where it could be compressed, such as the carpal tunnel or the pronator teres. The objective of this review is to summarize the current knowledge on the median nerve's anatomy: anatomical variations (branches, median-ulnar communicating branches), fascicular microanatomy, vascularization, anatomy of compression sites, embryology, ultrasonographic anatomy. The links between its anatomy and clinical, surgical or diagnostic applications are emphasized throughout this review.

The indications and donor-site morbidity of tibial cortical strut autografts in the management of defects in long bones.

Aims: The primary aim of this study was to determine the morbidity of a tibial strut autograft and characterize the rate of bony union following its use. Patients and Methods: We retrospectively assessed a series of 104 patients from a single centre who were treated with a tibial strut autograft of > 5 cm in length. A total of 30 had a segmental reconstruction with continuity of bone, 27 had a segmental reconstruction without continuity of bone, 29 had an arthrodesis and 18 had a nonunion. Donor-site morbidity was defined as any event that required a modification of the postoperative management. Union was assessed clinically and radiologically at a median of 36 months (IQR, 14 to 74). Results: Donor-site morbidity occurred in four patients (4%; 95% confidence interval (CI) 1 to 10). One patient had a stress fracture of the tibia, which healed with a varus deformity, requiring an osteotomy. Two patients required evacuation of a haematoma and one developed anterior compartment syndrome which required fasciotomies. The cumulative probability of union was 90% (95% CI 80 to 96) at five years. The type of reconstruction (p = 0.018), continuity of bone (p = 0.006) and length of tibial graft (p = 0.037) were associated with the time to union. Conclusion: The tibial strut autograft has a low risk of morbidity and provides adequate bone stock for treating various defects of long bones. Cite this article: Bone Joint J 2018;100-B:667-74.

Pronation and supination of the hand: Anatomy and biomechanics.

Proper functioning of the hand relies on its capacity to rotate and point the palm upward (i.e. supination) or downward (i.e. pronation) when standing up with the elbow in 90° flexion. Hand rotation is possible because of forearm rotation and also rotation of the whole upper limb at the shoulder. Two distinct mechanisms contribute to hand rotation: one in which the ulna is immobile and another in which the ulna is mobile. In this review, we first summarize how evolution of the human species has led to the progressive development of specific forearm anatomy that allows for pronation and supination. Then we analyze how the three joints of the forearm (i.e. proximal, middle and distal radioulnar joints), in association with the characteristic shape of both forearm bones, allow the forearm to rotate around a single axis. Lastly, we describe the neuromuscular anatomy that controls these complex rotational movements. The anatomical and biomechanical points developed in this paper are analyzed while considering clinical applications.

Shear waves elastography for assessment of human Achilles tendon's biomechanical properties: an experimental study.

INTRODUCTION: Achilles tendon is the most frequently ruptured tendon, but its optimal treatment is increasingly controversial. The mechanical properties of the healing tendon should be studied further. Shear waves elastography (SWE) measures the shear modulus, which is proven to be correlated to elastic modulus in animal tendons. The aim of our study was to study whether the shear moduli of human cadaveric Achilles tendon, given by SWE, were correlated with the apparent elastic moduli of those tendons given by tensile tests. MATERIALS AND METHODS: Fourteen cadaveric lower-limbs were studied. An elastographic study of the Achilles tendon (AT) was first done in clinical-like conditions. SWE was performed at three successive levels (0, 3 and 6cm from tendon insertion) with elastographic probe oriented parallel to tendon fibers, blindly, for three standardized ankle positions (25° plantar flexion, neutral position, and maximal dorsal flexion). The mean shear moduli were collected through blind offline data-analysis. Then, AT with triceps were harvested. They were subjected to tensile tests. A continuous SWE of the Achilles tendon was performed simultaneously. The apparent elastic modulus was obtained from the experimental stress-strain curve, and correlation with shear modulus (given by SWE) was studied. RESULTS: Average shear moduli of harvested AT, given by SWE made an instant before the tensile tests, were significantly correlated with shear moduli of the same AT made at the same level, previously in clinical-like condition (p<0.05), only in neutral position. There was a statistical correlation (p<0.005) and a correlation coefficient R² equal to 0.95±0.05, between shear moduli (SWE) and apparent elastic moduli (tensile tests), for 11 tendons (3 tendons were inoperable due to technical error), before a constant disruption in the correlation curves. DISCUSSION: We demonstrated a significant correlation between SWE of Achilles tendon performed in clinical-like conditions (in neutral position) and SWE performed in harvested tendon. We also found a correlation between SWE performed on harvested tendon and apparent elastic moduli obtained with tensile tests (for 11 specimens). As a consequence, we can suppose that SWE of AT in clinical-like conditions is related to tensile tests. To our knowledge, the ability of SWE to reliably assess biomechanical properties of a tendon or muscle was, so far, only demonstrated in animal models. CONCLUSION: SWE can provide biomechanical information of the human AT non-invasively.

Hinged elbow fixator: an extracorporeal technique to position the hinge based on an original guidewire device.

INTRODUCTION: The application of a hinged elbow external fixator is technically demanding because the hinge axis must coincide exactly with the flexion-extension axis of the elbow. The standard technique involves inserting a 3-mm K-wire freehand into the distal humerus to materialize the flexion-extension axis. We designed a guidewire device for extracorporeal hinge positioning without K-wire insertion. In a cadaver study, we compared freehand K-wire insertion and our extracorporeal technique. METHODS: In 12 cadaveric elbows, we induced acute elbow instability by sectioning the medial collateral ligament complex and the anterior and posterior capsule. A hinged external fixator was applied to each elbow using both techniques. The outcome measures were procedure duration, number of image-intensifier shots (as a measure of radiation exposure), and passive motion range after fixator implantation. RESULTS: Compared with the freehand K-wire technique, the extracorporeal technique provided greater range of motion and significantly lower values for procedure duration and number of image-intensifier shots. Data dispersion was less marked with the extracorporeal technique, indicating better reproducibility. CONCLUSION: The extracorporeal technique based on a guidewire device enabled non-invasive positioning of a hinged elbow external fixator. This technique was faster, less irradiating, and more reproducible than the freehand K-wire technique.

Acute bilateral posterior dislocation of the shoulder: one-stage reconstruction of both humeral heads with cancellous autograft and cartilage preservation.

We present a case of bilateral posterior shoulder dislocation after an epileptic seizure. The anterior humeral-head impression fracture was 60% of the articular surface on the right shoulder and 30% on the left shoulder. We performed an early one-stage reconstruction of both humeral heads. A cancellous autograft was used on the left side and an iliac cortico-cancellous autograft on the right side, with preservation of the patient's cartilage. Three years later, the clinical and morphological results were excellent. The discussion focuses on surgical options that range from conservative treatment with excision of the damaged cartilage to immediate hemiarthroplasty. This case is original because of the preservation of the patient's cartilage during reconstruction.

[Ultrasonography for hand surgeons (lecture from the 46th meeting of French Society of Hand Surgery)]. / L'échographie pour le chirurgien de la main (conférence d'enseignement XLV(e) congrès de la Société française de chirurgie de la main).

Ultrasound examination is inexpensive, easily accessible and has numerous applications. Its diagnostic or even therapeutic use is developing in the context of hand surgery. The purpose of this work is to review the literature dealing with hand ultrasonograpy by recalling its physical basis and by showing the normal and pathological aspects of different structures and pathologies.

The intra-operative radius joystick test to diagnose complete disruption of the interosseous membrane.

Disruption of the interosseous membrane is easily missed in patients with Essex-Lopresti syndrome. None of the imaging techniques available for diagnosing disruption of the interosseous membrane are completely dependable. We undertook an investigation to identify whether a simple intra-operative test could be used to diagnose disruption of the interosseous membrane during surgery for fracture of the radial head and to see if the test was reproducible. We studied 20 cadaveric forearms after excision of the radial head, ten with and ten without disruption of the interosseous membrane. On each forearm, we performed the radius joystick test: moderate lateral traction was applied to the radial neck with the forearm in maximal pronation, to look for lateral displacement of the proximal radius indicating that the interosseous membrane had been disrupted. Each of six surgeons (three junior and three senior) performed the test on two consecutive days. Intra-observer agreement was 77% (95% confidence interval (CI) 67 to 85) and interobserver agreement was 97% (95% CI 92 to 100). Sensitivity was 100% (95% CI 97 to 100), specificity 88% (95% CI 81 to 93), positive predictive value 90% (95% CI 83 to 94), and negative predictive value 100%). This cadaveric study suggests that the radius joystick test may be useful for detecting disruption of the interosseous membrane in patients undergoing open surgery for fracture of the radial head and is reproducible. A confirmatory study in vivo is now required.

Posterior reversible encephalopathy syndrome in a context of isolated cervical spine fracture: CT angiogram as an early detector of blunt carotid artery trauma.

Blunt carotid injury associated with cervical spine fractures is a rare entity but potentially lethal. An initial, clinically silent period can be misleading. Prompt diagnosis and treatment are mandatory to avoid neurological damages and death. We present the case of a 36-year-old man diagnosed with an isolated cervical spine fracture, where an associated carotid artery lesion was initially overlooked and diagnosis was made after development of a neurological deterioration secondary to a posterior reversible encephalopathy syndrome (PRES). We discuss a simple algorithm that can be used to make the diagnosis, even during the clinically asymptomatic period of this injury.

Cranial nerves neuropraxia after shoulder arthroscopy in beach chair position.

We report a case of neuropraxia of the 9th, 10th and 12th cranial nerve pairs after arthroscopic rotator cuff repair in the beach chair position. The elements in the medical file seem to exclude an intracranial cause of the lesions and support a mechanical, extracranial cause due to intubation and/or the beach chair position. This clinical case report shows the neurological risks of the beach chair position during arthroscopic shoulder surgery and presents the essential safety measures to prevent these risks.

The middle radioulnar joint and triarticular forearm complex.

The forearm is composed of the radial and ulnar shafts, which are linked by the interosseous membrane and intercalated between the elbow and wrist. The radius and ulna are connected by three joints, the proximal, middle, and distal radioulnar joints. The forearm ensures pronation/supination and longitudinal load transfer. The biomechanical and clinical relevance of the proximal and distal radioulnar joints is well established. In contrast, the middle radioulnar joint was considered relatively unimportant until studies published in the last decade showed that it fulfils crucial biomechanical functions and is of considerable clinical significance. We believe the conventional concept in which the forearm is viewed as part of either the elbow or the wrist is outdated and that a more relevant concept describes the forearm as a triarticular complex that functions as a full-fledged entity. In this concept, the three forearm radioulnar joints (proximal, middle, distal) work together to provide stability, mobility and load transfer. Here, we will argue for the relevance of the triarticular complex concept based on published data about forearm biomechanics and pathological conditions.

Percutaneous retrograde screw fixation of non-displaced fractures of the scaphoid waist: an antirotation wire may not be necessary.

Some authors recommend using an antirotation wire when performing percutaneous screw fixation of acute non-displaced scaphoid waist fractures. The aim of this study of 21 cadaveric wrists was to assess the usefulness of such a wire in Herbert's B2-type fractures. A B2-type fracture was created experimentally on each scaphoid. An antirotation wire was inserted in eight wrists. Retrograde percutaneous fixation using a double-threaded headless cannulated screw was performed on all wrists. Computed tomography was used to measure interfragmentary rotation. No interfragmentary rotation was noted in either group. Our study suggests that using an antirotation wire may be unnecessary when performing retrograde percutaneous screw fixation of isolated B2-type scaphoid fractures.

[Bizarre parosteal osteochondromatous proliferation (Nora's lesion): two cases]. / La lésion de Nora ou Bizarre Parosteal Osteochondromatous Proliferation: à propos de 2 cas

The lesion Nora described in 1983 as a bizarre parosteal osteochondromatous proliferation (BPOP) is a member of a group of osteocartilaginous surface lesions. BPOP is infrequent but new cases are regularly reported. We report two new cases with an unusual localization (ilion and distal humerus) and unusual size (9 cm for the iliac lesion). In light of these cases and reports in the literature, the main differential diagnoses of BPOP are exostosis and parosteal osteosarcoma.

Ligamentoplasty of the forearm interosseous membrane using the semitendinosus tendon: anatomical study and surgical procedure.

Total longitudinal disruptions of the interosseous membrane can allow proximal radius migration and are seen in Essex-Lopresti lesions. We propose an original technique of ligamentoplasty using the semitendinosus tendon. The graft corresponds to the forearm rotation axis for an optimized isometry and longitudinal stabilization. Our ligamentoplasty technique was performed on ten fresh frozen right forearms. We successively assessed the innocuousness, efficiency and resistance of the ligamentoplasty. The ligamentoplasty induced neither passive limitation of pronation-supination nor neurovascular lesions. It prevented from radius proximal migration. The mean load to failure was 28 kg at both ulnar and radial sides of the graft. Our technique is original for the type and position of the graft. It seems safe, efficient and resistant enough for in vivo procedures. This technique decreases longitudinal loads on the radius. It should be indicated in patients with Essex-Lopresti syndrome, in association with radial head internal fixation or arthroplasty.

[Arthroscopic treatment of shoulder fractures.] / Traitement arthroscopique des fractures articulaires de l'épaule.

Therapeutic options for shoulder joint fractures include conservative treatment or surgery, but indications for either treatment remain vague. Arthroscopic treatment of glenoid fractures and greater tuberosity fractures represents an alternative and allows anatomical reduction and reliable fixation with decreased soft tissue trauma. With this minimally invasive technique, large muscular dissections are avoided and postoperative recovery is shortened. This technique also allows a complete joint inspection and a more accurate diagnosis for associated injuries than conventional imaging methods. Arthroscopy is a useful diagnostic tool that may avoid underestimation of these associated injuries (labrum, rotator cuff tendons, cartilage) and is also helpful for treating these lesions in the same time. However, arthroscopic treatment of shoulder fractures needs a learning curve depending on surgeon's experience in shoulder arthroscopy. At present, indications for arthroscopic treatment of shoulder fractures are limited to anterior or posterior glenoid rim fractures and some greater tuberosity fractures. This selection is best made using preoperative computed tomography and especially 2D reconstruction.

[Arthroscopic treatment of shoulder fractures]. / Traitement arthroscopique des fractures articulaires de l'épaule.

Therapeutic options for shoulder joint fractures include conservative treatment or surgery, but indications for either treatment remain vague. Arthroscopic treatment of glenoid fractures and greater tuberosity fractures represents an alternative and allows anatomical reduction and reliable fixation with decreased soft tissue trauma. With this minimally invasive technique, large muscular dissections are avoided and postoperative recovery is shortened. This technique also allows a complete joint inspection and a more accurate diagnosis for associated injuries than conventional imaging methods. Arthroscopy is a useful diagnostic tool that may avoid underestimation of these associated injuries (labrum, rotator cuff tendons, cartilage) and is also helpful for treating these lesions in the same time. However, arthroscopic treatment of shoulder fractures needs a leaming curve depending on surgeon's experience in shoulder arthroscopy. At present, indications for arthroscopic treatment of shoulder fractures are limited to anterior or posterior glenoid rim fractures and some greater tuberosity fractures. This selection is best made using preoperative computed tomography and especially 2D reconstruction.