Digital vs Conventional OSCE in Orthopedic Surgery: A Feasibility Cross-Sectional Study.

OBJECTIVE: Remote OSCEs (Objective Structured Clinical Examination) are an alternative evaluation method during pandemic periods but they have never been evaluated in orthopedic surgery. We aimed to evaluate whether remote OSCEs would be feasible, and efficient for assessment of undergraduate medical students. METHODS: A cross-sectional study was performed. Thirty-four students were randomly assigned into 2 equal groups, either the conventional OSCE group or the digital OSCE group. Three types of skills were assessed: technical procedure, clinical examination, and radiographic analysis. Students were graded and they filled in a satisfaction questionnaire for both types of OSCEs. RESULTS: The mean score, out of 20, was 14.3 ± 2.5 (range 9.3-19) for the digital sessions, versus 14.4 ± 2.3 (range 10-18.6) for conventional sessions (p = 0.81). Bland Altman Plot showed that 88% of students scored within agreement. The average global feedback was different for item repeatability, relevance, and OSCEs preference (p < 0.0001, p = 0.0001, and p < 0.0001 respectively). However, they did not report differences for the item concerning the organization (p = 0.2). CONCLUSION: The results of this comparative study between digital and conventional OSCEs showed comparable distance learning scores between the 2 groups, whatever the skill assessed. However, the student's evaluation showed some reticence to conduct again OSCEs remotely.

Anatomical variations in the sensory innervation of the dorsal surface of the first digit space, a cadaveric study with clinical consequences.

INTRODUCTION: Radial nerve palsy is a classical complication of a humeral shaft fracture. In clinical practice, motor palsy of the radial nerve is sometimes observed without an abnormality felt in the sensory territory. HYPOTHESIS: We hypothesised that this dissociation between sensory and motor involvement is related to anatomical variations of the sensory innervation of the dorsal surface of the first digit space, thus, we decided to study the nature and frequency of these variations. MATERIAL AND METHOD: A cadaveric study was conducted on 24 upper limbs to analyse the truncal origin of the sensory branches innervating the dorsal surface of the first digit space. RESULTS: The sensory branch of the radial nerve (SBRN) participated in the innervation of the dorsal surface of the first digit space in 22 limbs, an anatomical variation was present in 2 cases with a mixed innervation by the SBRN and the lateral cutaneous nerve of forearm (LCNF) in 1 case and singular innervation by LCNF, with no SBRN involvement, in 1 case. Communications between SBRN and LCNF were found in 7 cases. DISCUSSION: Pure motor radial damage, without a sensory deficit of the dorsal surface of the first digit space, does not preclude a complete traumatic injury of the radial nerve. The sensory innervation of this region can be relayed by a branch of the LCNF. LEVEL OF EVIDENCE: IV; cadaveric study.

Deciphering pathological remodelling of the human cartilage extracellular matrix in osteoarthritis at the supramolecular level.

The extracellular matrix (ECM) of articular cartilage is a three-dimensional network mainly constituted of entangled collagen fibrils and interfibrillar aggrecan aggregates. During the development of osteoarthritis (OA), the most common musculoskeletal disorder, the ECM is subjected to a combination of chemical and structural changes that play a pivotal role in the initiation and the progress of the disease. While the molecular mechanisms involved in the pathological remodelling of the ECM are considered as decisive, they remain, however, not completely elucidated. Herein, we report a relevant way for unravelling the role and nature of OA progress on human cartilage tissues, in terms of chemical composition and morphological and mechanical properties at the level of supramolecular assemblies constituting the cartilage ECM. For this purpose, we used X-ray photoelectron spectroscopy (XPS), and developed an innovative methodological approach that provides the molecular composition of the ECM. Moreover, we used atomic force microscopy (AFM) to probe the tissues at the level of individual collagen fibrils, both imaging and force spectroscopy modes being explored to this end. Taken together, these nanoscale characterization studies reveal the existence of two stages in the OA progress. At the early stage, a marked increase in the aggrecan and collagen content is observed, reflecting the homeostatic chondrocyte activity that tends to repair the cartilage ECM. At the late stage, we observe a failed attempt to stabilize and/or restore the tissue, yielding significant degradation of the supramolecular assemblies. This suggests an imbalance in the chondrocyte activity that turns in favor of catabolic events. Chemical changes are also accompanied by ECM structural changes and stiffening. Interestingly, we showed the possibility to mimic the imbalanced activities of chondrocytes by applying enzymatic digestions of healthy cartilage, through the combined action of hyaluronidase and collagenase. This yields damage strictly analogous to that observed at high OA severity. These findings bring mechanistic insights leading to a better understanding of the mechanism by which OA is initiated and progresses in the cartilage ECM. They offer guidelines for the development of curative treatments, such as targeting the homeostatic balance of chondrocyte metabolism through the control of enzymatic reactions involved in catabolic processes.

Ankle syndesmosis biomechanical evaluation by shear-waves elastography in healthy young adults: Assessment of the reliability and accuracy of the measurements and definition of a corridor of normality.

BACKGROUND: Aims of this study were: 1/ to evaluate the shear wave speed (SWS) properties of the anteroinferior tibiofibular ligament (AITFL) and the distal interosseous membrane (DIOM) in neutral, dorsal flexion and plantar flexion positions in a cohort of healthy adult volunteers; 2/ to assess the reliability and reproducibility of these measurements. METHODS: Both ankles were analyzed by shear wave elastography (SWE) in 20 healthy patients (10 females/10 males) standing on a hinge support with their ankles in neutral, 20° dorsal flexion and 30° plantar flexion positions. Stiffness of AITFL and DIOM was evaluated by SWS measurement. RESULTS: The SWS of AITFL and DIOM were minimal in the plantar flexion position (4.28 m/s [2.65-5.11] and 3.35 m/s [1.69-4.55], respectively). It increased significantly for both ligaments in neutral position (4.69 m/s [3.53-5.71] and 3.81 m/s [1.91-4.74], respectively; p < 0.0001), and reached their maximum values in dorsal flexion (6.58 m/s [5.23-8.34] and 4.79 m/s [3.07-6.19], respectively; p < 0.0001). There was no correlation between each ligament regardless the positions. SWS of AITFL was independent of demographic characteristics analyzed. SWS of DIOM was negatively correlated with height in dorsal flexion (ρ = -0.35; p = 0.03) and in plantar flexion (ρ = -0.37; p = 0.02). Female gender was associated with increased DIOM SWS in neutral (p = 0.005), dorsal flexion (p = 0.003), and plantar flexion (p = 0.001) positions. Moreover, foot morphology (foot arch, hind foot frontal deviation) did not impact AITFL nor DIOM SWS. Inter- and intra-observer measurements were all good or excellent. CONCLUSION: The AITFL and DIOM, stabilizers of the distal tibiofibular syndesmosis, increase in stiffness while dorsal flexion increases. This study describes a reliable and reproducible protocol to assess their stiffness by SWE, and defines a corridor of normality.

An ultra-thinned groin flap for reconstruction of complete digital ring avulsion injuries.

In complete digital ring avulsions, amputation is usually carried out when replantation of the avulsed tissue is not an option or has failed. The purpose of this study was to report our experience in treating Urbaniak Class III degloved fingers using an ultra-thinned pedicled groin flap. Sixteen patients from ages 11 to 26 years were included. In all cases, the flexor digitorum superficialis tendon, extensor apparatus and proximal interphalangeal joint were intact. Rehabilitation included immediate active mobilization, with flap division at day 21. At a mean follow-up of 15 months, all patients but one were satisfied with the appearance. Two had mild subjective cold intolerance. No flap failure was recorded. The mean total active motion was 183° and the mean QuickDASH score was 8.8/100. Patients recovered S1 sensibility according to the Mackinnon and Dellon classification. The ultra-thinned groin flap has proved to be a reliable technique for non-replantable ring avulsions.Level of evidence: IV.

Transfer of a C7 Fascicle for the Pectoralis Major to the Suprascapular Nerve: A 3-Year Follow-Up Patient Series.

BACKGROUND: In patients with C5-C6 brachial plexus injury, spinal accessory nerve transfer to the suprascapular nerve is usually performed for the restoration of shoulder abduction. In order to minimize donor deficits, we transferred one fascicle of the ipsilateral C7 root, dedicated to the pectoralis major muscle, to the suprascapular nerve. METHODS: Ten patients with a mean age of 33 years (range, 19 to 51 years) were operated on at a mean delay of 4 months after their trauma (range, 2 to 7 months). Patients had C5-C6 brachial plexus palsy with avulsed roots on spinal magnetic resonance imaging scan. In addition to the partial C7 transfer, patients sustained nerve transfers to the posterior branch of the axillary nerve and to the motor branches of the musculocutaneous nerve for the biceps and brachialis muscles. RESULTS: At a mean follow-up of 36 months (range, 29 to 42 months), mean shoulder abduction and external rotation ranges of motion were, respectively, 99 degrees (range, 60 to 120 degrees; p = 0.001) and 58 degrees (range, 0 to 80 degrees; p = 0.001). In nine patients, shoulder abduction strength was graded M4, according the British Medical Research Council grading scale, against 1.6 kg (range, 1 to 2 kg), and was graded M3 in one patient. External rotation strength was graded M4 in nine patients and M3 in one patient. Residual strength of the pectoralis major muscle was graded M4+ in every patient. CONCLUSIONS: C7 partial transfer to the suprascapular nerve showed satisfactory results at long-term follow-up for active shoulder abduction and external rotation recovery in C5-C6 brachial plexus palsies. This technique replaced spinal accessory nerve transfer in the authors' practice. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Sarcomas of the hand: A retrospective series of 26 cases.

BACKGROUND: Hand sarcomas frequently suffer from a delayed diagnosis, and the current guidelines for their management are often not followed. METHODS: The objectives of our study were to determine: (1) the rate of inadequate initial treatments; (2) the rates of mortality, recurrence, and complementary excision in a cohort of patients with a sarcoma of the hand who were treated at our reference center between 2000 and 2015. RESULTS: The series comprised 26 patients (mean age 40 years). Of the 20 patients not initially treated at a reference center, 17 had inadequate initial treatment. Of the six patients treated at our center, one had inadequate initial care. Significantly more patients had inadequate initial care outside a reference center (p=0.0045). The cumulative probabilities of recurrence or metastases at 5 years were 15% and 30%, respectively. Survival by cumulative incidence was 71% at 5 years and 56% at 10 years. CONCLUSIONS: Sarcomas of the hand are a deadly pathology. All diagnostic uncertainty warrants referral of the patient to a reference center. LEVEL OF PROOF: IV.

Induced membrane technique applied to the forearm: Technical refinement, indications and results of 13 cases.

INTRODUCTION: The unique anatomical characteristics of the forearm bones makes their reconstruction challenging. The aim of this study was to report the surgical methods and results of the induced membrane technique applied to traumatic forearm bone defects. MATERIAL AND METHODS: We evaluated retrospectively a case series of 13 patients operated between 2010 and 2017. The first surgical step consisted of debridement of the fracture site and implantation of a cement spacer with appropriate fixation. The anatomy of the forearm skeleton had to be restored. The second step, done 6 weeks later, consisted of removing the cement spacer and applying cancellous bone autograft harvested from the iliac crest. The outcome measures were radiological bone union, need for surgical revision, and postoperative wrist range of motion. RESULTS: All 13 patients were men, with a mean age of 39 years (18-67). The average follow-up was 2.5 years. Eleven patients were suffering from a nonunion and two from a post-traumatic bone defect. Six patients had an identified preoperative infection. Three patients had previously undergone an unsuccessful treatment for their nonunion with bone addition. The maximum length of bone reconstruction was 12 cm. Union was achieved in 12 of 13 patients in a mean of 5 months (3-8). The other patient died during the postoperative course. Two patients needed revision surgery: ulnar shortening osteotomy (1 case) and additional tendon reconstruction (1 case). The mean pronosupination range was 123° on average (55-180°). The mean flexion-extension range was 106° (90-130°). CONCLUSION: The induced membrane technique is a reliable reconstruction technique that is well suited to reconstruction of the forearm skeleton. LEVEL OF EVIDENCE: IV, retrospective study.

Comparison of "Bilboquet" device and locking plate for surgical treatment of proximal humerus complex fractures at two years follow-up.

PURPOSE: Surgical treatment of three or four part fractures of the proximal humerus is complex. Different conservative techniques have been described. The main goal of this study was to compare the clinical and radiological outcomes of Bilboquet and locking plate at two year follow-up. METHODS: This is a retrospective, comparative study, with a continuous series of 41 patients. Bony fixation was achieved with a Bilboquet device in 22 patients or a locking plate in 19 patients. Patient evaluation included clinical data: shoulder range of motion, Constant-Murley shoulder score and DASH (Disabilities of the Arm, Shoulder and Hand) score, and imaging using standard shoulder X-rays. RESULTS: Of the 41 patients included, 1 patient was lost to follow-up in the locking plate group. At a mean follow-up of 24 months patients in Bilboquet group showed a Constant score higher than in locking plate (p = 0.02). Range of motion and DASH score were not significantly different between the two groups. avascular necrosis occured in three patients of Bilboquet group (14%) versus in two patients in the locking plate group (11%) (p > 0.5). Complication and reintervention rate were non-significantly higher in the locking plate group than in the Bilboquet group (37 vs 14%). CONCLUSION: Bilboquet and locking plate give good functional outcomes in complex proximal humerus fractures. However, the Bilboquet device appears to provide better functional results than locking plate at mid-term follow-up.

Ulnar neuropathy at the elbow.

At the elbow, the ulnar nerve (UN) may be the site of a static compression (by the cubital tunnel retinaculum and Osborne's ligament between the two heads of the flexor carpi ulnaris), or a dynamic compression, especially when the nerve is unstable (subluxation/dislocation outside the ulnar groove). The clinical basis for the diagnosis of ulnar neuropathy involves looking for subjective and objective signs of sensory and/or motor deficit in the ulnar nerve's territory in the hand, a pseudo-Tinel's sign, and doing manipulations to provoke UN irritation. The diagnosis is confirmed by electromyography and ultrasonography. In the early stages, patient education and elimination of flexion postures or repeated elbow flexion motions can provide relief. If this fails or signs of sensory and/or motor deficit are present, surgical treatment is proposed. If the nerve is stable, in-situ nerve decompression is typically done as the first-line treatment. If the nerve is unstable, anterior nerve transposition - generally subcutaneous - or more rarely, a medial epicondylectomy can be done. If surgical treatment fails, the patient's history is reviewed, and diagnostic tests can be repeated. Except in cases of a fibrotic scar, the main causes of failure are neuroma of a branch of the medial cutaneous nerve of the forearm, instability of the nerve and persistence of a compression point. In the latter two cases, surgical revision is justified and anterior nerve transposition or epicondylectomy can be proposed.

C5/C6 brachial plexus palsy reconstruction using nerve surgery: long-term functional outcomes.

INTRODUCTION: In traumatic proximal brachial plexus lesions (i.e., C5/C6), reconstruction of the musculocutaneous, axillary and suprascapular nerves yields satisfactory short- and medium-term functional outcomes. HYPOTHESIS: Early functional outcomes after nerve surgery will be maintained in the long-term. METHODS: A retrospective analysis was done using the medical records of 29 patients with C5/C6 palsy treated by nerve surgery. Active range of motion and strength at the elbow (i.e., flexion) and shoulder (i.e., flexion, abduction, external rotation with the elbow at the side of the body and with the arm 90° abducted ) were evaluated clinically using a goniometre and the British Medical Research Council grading scale, respectively. RESULTS: At a mean follow-up of 46±15 months (25;76), the mean active elbow flexion was 126°±18° (90;150) and the mean strength was 3.8±0.5 (2;4). At the shoulder, mean active flexion, abduction, external rotation with the elbow at the side of the body and with the arm 90° abducted were 109°±39° (0;180), 99°±38° (0;180°), 12°±34° (-80;70) and 3°±21° (-40;50), while mean strength was 3.6±0.8 (0;4), 3.6±0.8 (0;4), 3.4±0.9 (0;4) and 2.5±1.2 (0;4), respectively. DISCUSSION: In cases of C5/C6 palsy, early nerve surgery yields satisfactory functional outcomes that are maintained over time for elbow flexion and shoulder elevation. However, when the teres minor is not reinnervated, it is difficult to restore satisfactory shoulder external rotation. LEVEL OF EVIDENCE: IV, Retrospective case study.

The Role of the Non-neuronal Cholinergic System in Inflammation and Degradation Processes in Osteoarthritis.

OBJECTIVE: The non-neuronal cholinergic system represents non-neuronal cells that have the biochemical machinery to synthetize de novo and/or respond to acetylcholine (ACh). We undertook this study to investigate this biochemical machinery in chondrocytes and its involvement in osteoarthritis (OA). METHODS: Expression of the biochemical machinery for ACh metabolism and nicotinic ACh receptors (nAChR), particularly α7-nAChR, in human OA and murine chondrocytes was determined by polymerase chain reaction and ligand-binding. We investigated the messenger RNA expression of the human duplicate α7-nACh subunit, called CHRFAM7A, which is responsible for truncated α7-nAChR. We assessed the effect of nAChR on chondrocytes activated by interleukin-1ß (IL-1ß) and the involvement of α7-nAChR using chondrocytes from wild-type (WT) and α7-deficient Chrna7-/- mice. The role of α7-nAChR in OA was explored after medial meniscectomy in WT and Chrna7-/- mice. RESULTS: Human and murine chondrocytes express the biochemical partners of the non-neuronal cholinergic system and a functional α7-nAChR at their cell surface (n = 5 experiments with 5 samples each). The expression of CHRFAM7A in human OA chondrocytes (n = 23 samples) correlated positively with matrix metalloproteinase 3 (MMP-3) (r = 0.38, P < 0.05) and MMP-13 (r = 0.48, P < 0.05) expression. Nicotine decreased the IL-1ß-induced IL-6 and MMP expression, in a dose-dependent manner, in WT chondrocytes but not in Chrna7-/- chondrocytes. Chrna7-/- mice that underwent meniscectomy (n = 7) displayed more severe OA cartilage damage (mean ± SD Osteoarthritis Research Society International [OARSI] score 4.46 ± 1.09) compared to WT mice that underwent meniscectomy (n = 9) (mean ± SD OARSI score 3.05 ± 0.9; P < 0.05). CONCLUSION: The non-neuronal cholinergic system is functionally expressed in chondrocytes. Stimulation of nAChR induces antiinflammatory and anticatabolic activity through α7-nAChR, but the anticatabolic activity may be mitigated by truncated α7-nAChR in human chondrocytes. In vivo experiments strongly suggest that α7-nAChR has a protective role in OA.

Clearing method for 3-dimensional immunofluorescence of osteoarthritic subchondral human bone reveals peripheral cholinergic nerves.

The cholinergic system plays a major anti-inflammatory role in many diseases through acetylcholine (Ach) release after vagus nerve stimulation. Osteoarthritis (OA) is associated with local low-grade inflammation, but the regulatory mechanisms are unclear. Local Ach release could have anti-inflammatory activity since articular cells express Ach receptors involved in inflammatory responses. Using the 3DISCO clearing protocol that allows whole-sample 3-dimensional (3D) analysis, we cleared human OA cartilage-subchondral bone samples to search for cholinergic nerve fibres able to produce Ach locally. We analysed 3 plugs of knee cartilage and subchondral bone from 3 OA patients undergoing arthroplasty. We found no nerves in the superficial and intermediate articular cartilage layers, as evidenced by the lack of Peripherin staining (a peripheral nerves marker). Conversely, peripheral nerves were found in the deepest layer of cartilage and in subchondral bone. Some nerves in the subchondral bone samples were cholinergic because they coexpressed peripherin and choline acetyltransferase (ChAT), a specific marker of cholinergic nerves. However, no cholinergic nerves were found in the cartilage layers. It is therefore feasible to clear human bone to perform 3D immunofluorescence. Human OA subchondral bone is innervated by cholinergic fibres, which may regulate local inflammation through local Ach release.

ALGINATE versus NPWT in the Preparation of Surgical Excisions for an STSG: ATEC Trial.

A calcium alginate dressing (ALGINATE) and negative pressure wound therapy (NPWT) are frequently used to treat wounds which heal by secondary intention. This trial compared the healing efficacy and safety of these 2 treatments. METHODS: This randomized, non-inferiority trial enrolled patients who underwent skin excision (>30 cm2), which was left open to heal by secondary intention. They received ALGINATE or NPWT by a centralized randomization. Follow-up was performed weekly until optimal granulation tissue was obtained. The primary outcome was time to obtain optimal granulation tissue for a split thickness skin graft take (non-inferiority margin: 4 days). Secondary outcomes were occurrence of adverse events (AEs) and impact of the treatments on the patient's daily life. RESULTS: ALGINATE and NPWT were applied to 47 and 48 patients, respectively. The mean time to optimal granulation was 19.98 days (95% CI, 17.7-22.3) with ALGINATE and 20.54 (95% CI, 17.6-23.5) with NPWT. Between group difference was -0.56 days (95% CI -4.22 to 3.10). The non-inferiority of ALGINATE versus NPWT was demonstrated. No AE related to the treatment occurred with ALGINATE versus 14 AEs with NPWT. There was no difference in the impact of the treatments on the patient's daily life. CONCLUSION: This trial demonstrates that ALGINATE has a similar healing efficacy to that of NPWT and that is markedly better with regard to patient safety.

Open reduction and internal fixation of three- and four-part proximal humeral fractures by intrafocal distraction: a clinical and radiographic study of thirty-two cases with five to ten years of follow-up.

PURPOSE: The disadvantage of ORIF of proximal humerus fracture (PHF) by intrafocal distraction is that once the device is inserted, it cannot be removed. This study was designed to evaluate the tolerance of such a titanium alloy device at five years of minimal follow-up (FU) and secondarily to assess the relevance of the osteosynthesis of these fractures. METHOD: Thirty-two patients operated for PHF and implanted with a titanium alloy device between 2009 and 2011 were reviewed: fifteen three-part fracture (3-PF) with mean age 65.2 ± seven years and mean FU at 86 months, and seventeen four-part (4-PF) with mean age 62.9 ± 12 years and mean FU at 88 months. RESULTS: There were no signs of clinical or radiological incompatibility to the metal. The lateral cortex of the humeral shaft at the wedge component level of the device was thinner than pre-operatively in half of the cases. For the fifteen 3-PF, the median raw and weighted constant score (CS) were 75 and 100, respectively. Only one case presented avascular necrosis (AVN). For the seventeen 4-PF, the median raw and weighted CS were 64 and 88, respectively. Seven cases presented AVN and none of them seven had initially a dorsomedial metaphyseal extension of the humeral head. Kaplan-Meier survivorship analysis, with 95% confidence interval, was calculated at 89.7% (79.7-100%) survivorship at 7.18 years of follow-up. CONCLUSIONS: This study shows no incompatibility of the titanium alloy device, radiological signs of localized stress shielding in half of the cases with no functional impact, excellent clinical and radiological evolution of the 3-PF, and AVN in all 4-PF without dorsomedial metaphyseal extension of the humeral head whereas most of cases without AVN had dorsomedial metaphyseal extension.

Induced-membrane treatment of refractory humeral non-union with or without bone defect.

INTRODUCTION: Treatment of humeral non-union with or without bone defect is complex, with non-negligible rates of complication and failure. Few reports focused on management of treatment failure. OBJECTIVE: The study hypothesis was that the induced-membrane technique associated in a 2-stage strategy to internal fixation provides systematic bone healing in refractory humeral non-union. MATERIAL AND METHODS: The study included 15 patients, with a median age of 46.6 years, with humeral non-union of a mean 24 months' progression and mean history of 3 attempted revision surgeries. Seven patients showed bone defect, exceeding 5cm in 2 cases. Six had history of radial palsy. RESULTS: Consolidation was achieved in all cases, at a mean 4.6 months. Ten patients underwent radial nerve transposition, 6 of whom had shown radial motor nerve palsy; all recovered within 2 to 5 months. There was 1 case of superficial infection, and 1 of seroma. DISCUSSION: The induced-membrane technique ensures bone healing due to the biological properties of the membrane; the main drawback is the need for 2-stage surgery. When bone defect exceeds 5cm, a multi-perforated fibula segment can be placed inside the membrane to increase primary stability and enhance bone integration. CONCLUSION: The induced-membrane technique is suited to humeral non-union, with or without bone defect. The 2-stage strategy is mandatory in case of suspected latent infection. In the 2-stage procedure, anteromedial radial nerve transposition facilitates the bone-graft stage. LEVEL OF EVIDENCE: IV, retrospective study.

Fast-track teaching in microsurgery.

INTRODUCTION: In France, microsurgery is taught in University diploma courses, for a mean 100hours (range, 45-120hours) extending over several months. This training, spread over the year, encounters problems of maintaining high-quality supervision and enduring acquisition of skills. These difficulties risk leading to withdrawal of certain courses, already suffering from funding issues and administrative requirements for animal welfare. MATERIAL AND METHOD: We report our experience with a 2-week module comprising nine 4-hour sessions (total, 36hours), with continuous supervision of 5 students in each of 2 groups (10 students), enabling personalized learning. At the end of each session, an assessment questionnaire was filled out by teachers and students. RESULTS: Students' scores increased from a mean 23.9/30 points (range, 20 - 30) at session 3 to 26.9 points (range, 23 - 30) at session 9 (p=0.012). At the end of session 3, students were grouped as good, average or beginners, based on the first assessments: i.e., with differences in level between groups at session 3. At the end of session 9, all 3 groups showed statistically comparable levels. Comparison between student and teacher questionnaire responses showed a significant discrepancy in 7 of the 10 cases in week 1, and no significant discrepancy in 7 of the 10 cases by the end of week 2. DISCUSSION: The efficacy of condensed learning is based on immediate repetition of exercises, following Ebbinghaus: without repetition, memory decays exponentially, whereas if the information is rapidly repeated, the curve flattens and memory is consolidated. The present rapid improvement in the acquisition of the principles of microsurgery stimulated the enthusiasm of both students and teachers for what is reputed to be a demanding type of training. The study showed that acquisition, assessed in terms of vascular suture reliability, was achieved by the end of a 36-hour module, regardless of the student's baseline level.

Anatomy of the posterior branch of the medial antebrachial cutaneous nerve: A cadaveric study.

PURPOSE: The posterior branch of the medial antebrachial cutaneous nerve (MACN) is at risk to be damaged during cubital tunnel surgery. The purpose of this study was to identify the location of the posterior branch of the MACN (PBMACN) in relation to surgical landmarks pertinent in cubital tunnel surgery. METHODS: We performed an anatomical study on 20 limbs from 13 fresh cadavers. The nerve was dissected from 10cm proximal to 10cm distal of the medial epicondyle. We measured the distance between the nerve and the medial epicondyle, and also the distance separating the PBMACN from the ulnar nerve passage between the two heads of the flexor carpi ulnaris. Measurements were performed with the elbow at 45° and 90° of flexion, as well as in full pronation and supination. RESULTS: After its emergence from the main trunk of the MACN, the posterior branch ran anteriorly to the medial epicondyle, taking an oblique direction toward the ulnar shaft. The PBMACN was in average 2.53cm under the medial epicondyle when the elbow was flexed at 45°, and 2.96cm when the elbow was flexed at 90°. Average distance between the PBMACN and the penetrating point of the ulnar nerve within the flexor carpi ulnaris was 1.54cm when the elbow was flexed at 45°, and 1.62cm when the elbow was flexed at 90°. Pronation and supination positions of the forearm did not significantly modify our measurements. CONCLUSIONS: Understanding the position of MACN posterior branch during ulnar nerve release surgery at the elbow may help in preventing iatrogenic injury. According to our measurements, incision and superficial dissection anterior to the medial epicondyle or distal to the ulnar nerve penetrating point between the two heads of the flexor carpi ulnaris should be avoided or done with an elbow flexed at 90°.

Reconstruction of lateral pinch in an isolated paralysis of the first dorsal interosseous muscle - A new surgical technique.

Lack of function of the first interosseous muscle (FDI) might be responsible for insufficient stabilisation of the index finger during lateral pinch, and may induce disability in hand function. The first cause of FDI palsy is ulnar nerve palsy. We describe a new tendon transfer to reanimate the FDI muscle, using the extensor indicis proprius tendon. The tendon is sectioned at its distal insertion and rerouted in the first extensor tendon compartment. We report one case of isolated first interosseous muscle palsy secondary to direct trauma. Preoperatively, the patient complained of a severe lack of strength during key pinch with an ulnarly deviated index finger. Thirty months postoperatively, the patient recovered active abduction of the index finger and lateral pinch was measured at 5.5kg (54N). Compared to the original Bunnell transfer our technique restores the native moment arm of the FDI muscle and does not require a tendon graft.

Three-dimensional-printed patient-specific Kirschner-wire guide for percutaneous fixation of undisplaced scaphoid fractures: a cadaveric study.

Undisplaced scaphoid waist fractures can be managed by percutaneous fixation. The purpose of this study is to compare percutaneous fixation using a three-dimensional (3-D)-printed guide with the conventional method in a cadaveric study. Twelve wrists were divided into two groups: standard fluroscopic technique group, and a patient-specific 3-D-printed guide group. In the patient-specific group, using high resolution CT scans, we manufactured a mould-guide including a wire guide sleeve aligned with the planned ideal path, and 3-D printed it. On postoperative CT scans we measured the angular deviation of the screw axis from the ideal axis, and compared the two groups. The angular deviation was significantly lower in the patient-specific guide group. We concluded that a 3-D-printed guide for scaphoid percutaneous fixation allows a more accurate placement of the screw than a fluoroscopy guide in our cadaveric model.