Innervation of digital joints: an anatomical overview.

INTRODUCTION: The innervation of the digital joints as well as the anatomical relationships of the articular branches is present in this anatomical work to determine the technical feasibility of a selective and efficient denervation of the digital joints. MATERIALS AND METHODS: A study of 40 distal interphalangeal (DIP), 40 proximal interphalangeal (PIP), 50 metacarpophalangeal (MCP), 10 interphalangeal (IP) of the thumb, and 10 trapezo-metacarpophalangeal (TMC) joints was performed on ten hands. Under magnification and a proper surgical approach, we collected the course, the source origin, the number of articular nerve branches, and their caliber. RESULTS: In total, 118 nerve branches arising from the proper palmar digital nerves were found on 10 DIP of each dissected long finger (n = 40). A total of 226 nerve branches were found on 10 PIPs of each long finger (n = 40), of which 204 branches (90.3%) had a palmar origin. Dorsal innervation was found for the ring and little finger, originating from the dorso-ulnar digital nerve. 212 branches were found on 10 MCP of long fingers (n = 40), including 87 branches of palmar origin (41.1%), 107 branches of dorsal origin (50.4%), and 18 branches of the motor branch of the ulnar nerve (8.5%). 42 articular branches directed to the TMC joint (n = 10) were found. 13 branches (31%) originated from the anterior sensory branch of the radial nerve, 13 branches (31%) originated from the lateral cutaneous nerve of the forearm, 5 branches (12%) originated from the palmar cutaneous branch of the median nerve, and 11 (26%) branches originated from the thenar branch of the median nerve. The involvement of the sensory anterior branch of the radial nerve was always present for the innervation of each TMC. DISCUSSION AND CONCLUSION: Our research shows that finger joints receive their primary innervation from small branches of the digital nerves with the exception of the MCP joint and the TMC joint. To obtain an efficient and a selective digital denervation for articular pain relief, it is necessary to plan the best surgical approach and it is crucial to recognize the articular nervous branch localization and source.

The position of the upper limb during shoulder arthroscopy does not affect the distance between axillary nerve and glenoid.

PURPOSE: The segment of the axillary nerve (AxN) near the glenoid rim is at risk of iatrogenic lesion during arthroscopic procedures. We hypothesize that the distance between the AxN and the glenoid rim is not modified by the patient's positioning. The primary objective was to compare the position of the AxN with the inferior glenoid rim in lateral decubitus or in beach chair and positions of the upper limb. METHODS: Sixteen shoulders were dissected in beach chair position with the shoulder in neutral rotation. Needle one was placed in the axillary nerve where it was the closest with the inferior glenoid rim. In lateral decubitus with traction and 70° of abduction needle two was placed in the AxN at the closest with the inferior glenoid rim. The glenoid rim was marked with a needle at 6 o'clock. In beach chair position, the distance between needle one and the glenoid needle was measured for six positions. In lateral decubitus, measures were done for two positions of abduction. In lateral decubitus with 70° of abduction, the distance between needle two and the glenoid needle was also measured. RESULTS: The mean distance between AxN and the inferior glenoid rim was 14.4 mm in reference position in beach chair. The results showed the absence of difference between the positions during surgery except for lateral decubitus with 70° of abduction. CONCLUSION: Our study showed that the position of the shoulder during arthroscopic procedures cannot take away the AxN from the inferior glenoid rim. LEVEL OF EVIDENCE: Level IV-basic science study.

Vascularization of the superficial circumflex iliac perforator flap (SCIP flap): an anatomical study.

INTRODUCTION: The superficial circumflex iliac artery perforator flap (SCIP) has gained widespread popularity as local or free flap to cover soft tissue defects. However, there are numerous anatomical variations in terms of size, location and reliability of its perforators This cadaveric study aimed to focus on the anatomical bases of this flap. MATERIALS AND METHODS: A bilateral dissection of seven cadavers was performed to harvest 14 flaps. Superficial circumflex iliac artery parameters, number, length and diameters of perforators were measured. Correspondent perforasomes were highlighted through semi-selective injections. RESULTS: The major perforator of the superficial branch had a mean caliber of 2.0 mm, and a mean length of 1.8 mm. The major perforator of the deep branch had a mean caliber of 2.1 mm and a mean length of 1.43 mm. The mean area of the superficial pattern perforasome was 178.6 cm2 and the mean measured surface of the deep pattern perforasome was 156.2 cm2. The descending branches of the deep branch anastomosing with the ascending branch of the lateral circumflex femoral artery were found in three cases. CONCLUSION: Several anatomical variations were observed in this anatomical study, but major perforators supplying large perforasomes were always found.

Anatomy of the cutaneous lymphatic system of the trunk: a clinico-anatomical study of 90 cutaneous melanomas.

PURPOSE: The cutaneous lymphatic system of the trunk is a complex network, the anatomical knowledge of which remains unclear. The lymphatic system plays a major role in the dissemination of lymphophilic cancers like melanomas. The aim of this study was to improve our knowledge, optimize the care of patients with cutaneous tumors of the trunk, and to use our clinical experience of the topography of pathologic lymph nodes related to cutaneous melanomas and depicted by lymphoscintigraphy. MATERIALS AND METHODS: This prospective study included 90 consecutive patients who had primary resection of cutaneous melanoma of the trunk between June 2011 and January 2015. All patients had lymphatic mapping by lymphoscintigraphy, followed by sentinel lymph node procedure. We compared data of lymphatic imaging (lymphoscintigraphy and SPECT-CT) and surgery. We divided the trunk into 36 regions based on cutaneous anatomical landmarks to determine the topography of the lymphatic system for each tumor. RESULTS: Our study showed cutaneous lymphatic drainage of melanomas of the trunk in 16 different areas. This drainage could be single or multiple. We observed that drainage could be controlateral in medial regions of the trunk, and lymphatic pathway could be retrograde. This drainage could be bilateral for medial regions and mainly into axillary areas for regions above L1 level. Posterior regions of the trunk had more diversity of drainage areas than anterior regions. CONCLUSIONS: Cutaneous lymphatic drainage of the trunk was not limited to axillary and inguinal areas, showed interindividual variability, and was single or multiple, unilateral or bilateral, and unpredictable.

[Original three-dimensional reconstruction of a case of metopism associated with a unilateral complete absence of the left frontal sinus: Clinical interest and review of the literature]. / Représentation tridimensionnelle originale d'un cas de métopisme associé à une agénésie unilatérale complète du sinus frontal gauche : intérêt clinique et revue de la littérature.

Metopism (complete persistence of the metopic suture in adults) is a rare but not exceptional variation of the calvaria. Hypoplasia or aplasia of the frontal sinus may be associated without evident correlation. Nevertheless, a misdiagnosis of these variations may have clinical consequences, especially in a traumatic context. The aim of this paper was to report a case of metopism associated with a unilateral aplasia of the left frontal sinus, originally illustrated with 3D image fusion volume rendering reconstructions.

Posterior tibial tendoscopy: Description of an accessory proximal portal and assessment of tendon vascularization lesion according to portal.

BACKGROUND: Posterior tibial tendoscopy was codified in 1997 by Van Dijck, who described a portal between 1.5 and 2cm proximally and distally to the tip of the medial malleolus. However, this approach does not allow proximal exploration of the posterior tibial tendon (PTT). We here describe an accessory portal 7cm proximal to the medial malleolus, enabling complete PTT exploration. METHODS: Posterior tibial tendoscopy was performed on 12 cadaver specimens, mapping PTT exploration and vascularization. RESULTS: The accessory portal enabled the whole PTT to be explored, from the myotendinous junction to the entry into the retromalleolar groove. PTT observation quality was improved compared to using a submalleolar portal. Dissection confirmed systematic presence of a vincula on the posterior side of the tendon, connected to the flexor digitorum longus (FDL) tendon, containing collateral vessels of the posterior tibial artery. None of these elements were damaged by the tendoscopy as long and the scope and motorized instruments were not rotated on the posterior side of the supramalleolar part of the PTT. CONCLUSIONS: This accessory entry portal provides complete PTT exploration without the risk of neurovascular bundle lesion.

A plea for the use of drawing in human anatomy teaching.

Descriptive human anatomy constitutes one of the main parts of the educational program of the first part of the medical studies. Professors of anatomy have to take into account the exponential evolution of the techniques of morphological and functional exploration of the patients, and the trend to open more and more the contents of the lectures of anatomy to clinical considerations. Basically, teaching requires a series of descriptive and educational media to set up, in front of the student, the studied structures and so to build the human body. More generally, lectures in morphological sciences try to develop three types of knowledge: declarative, procedural, and conditional. Traditionally in France "basic or first" anatomy is taught in amphitheater and in big groups by building each structure or region on a blackboard with colored chalk that allows a relief stake of certain structures and builds in two dimensions a three-dimensional organization. Actually, the blackboard is and stays for us an excellent media of non-verbal expression.

The morphological and morphometric analysis of the variant patterns of the tricipital aponeurosis: a new anatomical classification with possible clinical implications.

BACKGROUND: Tricipital aponeurosis (TA) has gained attraction as a constant and reliable landmark to identify the location of radial nerve in the setting of fracture distal humeri. The aponeurosis itself shows variant anatomical patterns. In this study, we intend to provide a comprehensive description and functional classification of observed anatomical variations with possible clinical implications. MATERIALS AND METHODS: Sixty arms belonging to 30 adult cadavers were studied. TA was examined grossly to document variations in its shape and classified accordingly. Subsequently, length and breadth of TA were measured. The distance of the radial nerve (RN) from the point of confluence and from the lateral border of TA was also measured (tricepso-radial distance [TRD]). These distances were correlated with the different patterns of TA obtained. RESULTS: Based on the shape of the proximal apex of TA or point of confluence and frequency of their occurrence, we propose a new classification of 4 patterns for the TA anatomy. Pattern I: classically seen as the triangular proximal apex (76.67%); pattern II: tongue shaped or blunt proximal apex (18.33%); pattern III: bifurcated or dual proximal apex (3.33%); pattern IV: as the absence of TA (1.67%). The mean of length and breadth of TA was 16.58 ± 2.05 cm and 3.61 ± 0.61 cm, respectively. The mean distance of RN from point of confluence and lateral border of TA was 3.57 ± 0.19 cm and 2.04 ± 0.56 cm, respectively. The length, breadth of TA and TRD differs amongst the different patterns of TA. CONCLUSIONS: Anatomical variations in the shape and size of TA are frequently encountered. The proposed, hitherto undescribed, classification may make operating surgeon aware of these morphological variations and help prevent iatrogenic injury to RN. Such classification is simple and unique; however, its success relies upon universal acceptance.

[Thrombosis of the posterior tibial artery complicating closed injury of the ankle]. / Thrombose de l'artère tibiale postérieure: une complication rare d'un traumatisme fermé de la cheville.

Closed ankle injury without fracture is a common finding in the emergency room. Outcome is generally spontaneously favorable, the injury having no long-term clinical impact. Exceptionally, these injuries can be associated with arterial damage. We report a case of an apparently benign closed ankle injury which was found to be associated with serious arterial damage. Forced dorsal flexion of the ankle joint during a traffic accident caused an arterial lesion without any apparent damage to the bone and joints. The posterior tibial artery was interrupted leading to subacute ischemia of the foot. The diagnosis was established 17 days after trauma. Revascularization could not be achieved and leg amputation was necessary. This case illustrates the difficulties encountered in this type of vascular injury. Most cases in the literature have also involved late diagnosis with often serious clinical impact. Clinicians should be aware of this rare complication of apparently benign ankle injury because of the risk of major loss of function.

[Treatment of thoracolumbar junction burst fractures (Magerl A3) by balloon kyphoplasty: anatomic study]. / Traitement des burst fractures (Magerl A3) de la charnière thoracolombaire par cyphoplastie à ballonnets: étude anatomique.

PURPOSE OF THE STUDY: Balloon kyphoplasty is a not widely used method for the treatment of vertebral burst fractures with displacement of the posterior wall. The purpose of this study was to measure the posterior height of the vertebral body and the posttraumatic canal surface area before and after balloon kyphoplasty for the treatment of burst fractures (Magerl A3). MATERIAL AND METHODS: This anatomic study was conducted on ten experimental burst fractures of the thoracolumar junction prepared on cadaver specimens. The surface area of the canal and the height of the posterior wall were measured by computed tomography before and after balloon kyphoplasty. These two variables were then compared with search for correlation. RESULTS: The posttraumatic canal surface area increased significantly after kyphoplasty (p=0.02). Gain in posterior height was not significant and there was no correlation between the two variables. Cement leakage into the canal was not observed. DISCUSSION: It is known that balloon kyphoplasty can re-establish anterior height and correct for the posttraumatic kyphosis in patients with compression fractures of osteoporotic vertebrae. The present cadaver study shows that when the posterior wall is displaced posteriorly, balloon expansion does not exaggerate the wall displacement. On the contrary, the posttraumatic canal surface area is increased due to the ligamentotaxis effect. CONCLUSION: Balloon kyphoplasty could be an alternative to posterior instrumentation for burst fractures without associated neurological deficit, even if the posterior wall is damaged. This technique can be used to reduce and stabilize the fracture while sparing the adjacent levels and limiting the risk inherent with an extensive surgical approach.

Validity of rotational laxity coupled with anterior translation of the knee: A cadaveric study comparing radiostereometry and the Rotab®.

BACKGROUND: In current practice, anterior cruciate ligament (ACL) tears can be diagnosed using several devices to measure anterior tibial translation and rotational knee laxity, but these measures are never collected together. The Rotab®, which yields simultaneous measurements of anterior tibial translation and passive lower limb rotation under stress, would therefore be advantageous in current practice, but its reliability has never been tested. AIM OF STUDY: To evaluate the accuracy and reliability of the Rotab® compared to the reference system, radiostereometric analysis (RSA). METHODS: This anatomical study was conducted on 14 lower limbs collected from fresh cadavers. Simultaneous measurements of anterior tibial translation and rotation were obtained with both systems, with antero-posterior (AP) forces of 134N and 250N using the Rotab®. Measurements were made on intact ACL and then repeated after ACL section. Variables were analyzed in univariate analysis by ANOVA, and the intraclass correlation coefficient (ICC) between the systems was determined by the Bland and Altman method. RESULTS: The difference between the two methods for evaluating anterior tibial translation was 0.05±0.98mm at 134N and 0.29±1.04mm at 250N. The correlation between the tests was high (r134=r250=0.97, p=0.8). The difference between the two methods for rotational laxity was 0.69±2.7° at 134N and 0.5±0.6° at 250N. The Rotab® showed a significant difference only at 250N for rotational laxity after the ACL tear. CONCLUSION: The Rotab® is a reliable device to measure rotational laxity coupled with anterior translation of the knee.

Do temperature variations at the bearing surface during gait affect polyethylene wear in Charnley low-friction arthroplasty of the hip? Simulator study comparing UHMWPE and highly cross-linked polyethylene.

INTRODUCTION: There are significant individual variations in the polyethylene (PE) wear of Charnley total hip arthroplasty (THA) in published studies. This could be in part related to variations in hip joint kinematics with abnormal heating at the metal/PE interface. The objectives of our hip simulator experiment were: (1) to measure PE wear as a function of hip kinematics and temperature variations at the interface; (2) to compare ultra-high molecular weight polyethylene (UHMWPE) to latest generation highly cross-linked PE (XLPE). HYPOTHESIS: Our hypothesis was that PE wear is correlated with temperature increases at the interface and thereby hip joint kinematics. MATERIAL AND METHODS: A simulator study was performed with four UHMWPE cups (Initiale™, Amplitude, Valence, France) and two XLPE cups (X3, Stryker, Kalamazoo, Michigan, USA) subjected to 5 million cycles each. The temperature at the femoral head/cup interface was measured every 500 cycles and implant dimensions were measured every 1 million cycles. RESULTS: The average temperature was 42°C for 1Hz and 50°C for 1.5Hz, no matter the type of PE tested. There was a large difference between UHMWPE and XLPE in their roughness, but no temperature variations or wear effects. Femoral head penetration after the first 1 million cycles was 0.18mm for the XLPE and 0.075mm UHMWPE on average. Between 1 and 5 million cycles, the penetration was less than 0.1mm per million cycles, with XLPE being similar to UHMPWE. DISCUSSION: Our study found a significant temperature increase at the bearing interface as a function of frequency. But there was no correlation between temperature variations and PE degradation. However, shear stresses were under-estimated because our simulator could not reproduce abduction and adduction movements. Our hypothesis was not confirmed because PE deformation was not correlated to temperature variations. XLPE was not better than UHMWPE in the particular conditions of this study. Simulator studies are limited because of the lack of standards on cycling and the simulator bath. LEVEL OF EVIDENCE: III-prospective case-control study in vitro.

[Evaluation of continuous nerve block for postoperative pain management in orthopaedic surgery]. / Evaluation de la mise en place d'un protocole d'analgésie postopératoire par cathéter périnerveux.

OBJECTIVE: After orthopaedic surgery, continuous nerve block analgesia provides effective postoperative pain relief. The practical use of these techniques may present problems. The purpose of this study was to assess the development of continuous block procedure for postoperative pain based on quality standard management and the effectiveness of initial training as an adjunct for introduction of these techniques. MATERIALS AND METHODS: A staff committee of anaesthesiologists established a specific practical working protocol. The medical and paramedical teaching sessions were immediately evaluated using a questionnaire. RESULTS: 214 consecutive patients were included. The incidence of side effects and complications were higher in the beginning of protocol. Constant improvement of these results was observed throughout the study. The rate patients with pain were 10%. The analysis of medical evaluation should permit to determine an acceptable level of quality. Most patients were satisfied with their management. CONCLUSION: Pain management quality assurance program provided an improvement in efficacy of postoperative pain management in our protocol. Further, evaluation may be required to assess the complete benefits of this new protocol as regards postoperative pain.

Radiographic evaluation of a novel horizontal dorsal intercarpal capsulodesis as a treatment of pre-arthritic scapholunate dissociation: a cadaver study.

Dorsal capsulodesis is an important part of the treatment of pre-arthritic scapholunate instability. We designed an experimental study using 14 fresh-frozen cadaver wrists to demonstrate the efficacy of a new horizontal dorsal intercarpal capsulodesis. We sectioned the scapholunate ligament to create a scapholunate dislocation. Several radiographic views, static and 'in stress', were recorded and we statistically compared the scapholunate interval before and after the section of the scapholunate ligament, and after the creation of the capsulodesis. The results showed a significant decrease of the scapholunate interval after the creation of the capsulodesis, especially in neutral and maximal ulnar deviation of the wrist. They also proved that our cadaveric model is reliable. This study demonstrated that this novel capsulodesis reduces the scapholunate interval in a cadaveric model.