Unoperated Side Research Articles

Erratum: Effect of Degree of Arterial Inflow on a Functioning Free Muscle Transplantation in a Rat Gracilis Model.

BACKGROUND Various surgical effects have previously been studied in an attempt to improve the functional outcome of the functioning free muscle transplantation (FFMT). However, the effect of the recipient arterial inflow on the FFMT has remained uninvestigated. This study was to investigate whether or not high flow versus low flow will affect the functional outcome of FFMT. METHODS Rat's left gracilis FFMT model was devised and the nutrient arterial inflow was modified. Twenty-four Lewis rats were divided evenly into relatively high (0.071 mL/min) and relatively low (0.031 mL/min) blood flow groups (p < 0.001). The unoperated right sides served as the controls. Cases resulting in poor function were additionally grouped as functional failure group for comparison. Regular swimming exercise was implemented at 1 month postoperatively for 3 months. Gracilis muscle functions were then evaluated. RESULTS Compared groups were: control (n = 13), low blood flow (n = 10), high blood flow (n = 8), and functional failure (n = 5). The control group showed superior functional results over the experimental groups (p < 0.0001). In the experimental group, successful group showed superior over the poor function group (p < 0.01). However, there was no significant difference between the high- and low-flow groups. CONCLUSION This is the first study to evaluate the effect of arterial inflow on the FFMT. The rate of blood flow (relatively high vs. low) has little effect on the functional outcome of transferred muscle. Survival of FFMT is the major concern while performing FFMT surgery. Arterial inflow while choosing the recipient artery is not the factor for consideration.

Effect of Degree of Arterial Inflow on a Functioning Free Muscle Transplantation in a Rat Gracilis Model.

Various surgical effects have previously been studied in an attempt to improve the functional outcome of the functioning free muscle transplantation (FFMT). However, the effect of the recipient arterial inflow on the FFMT has remained uninvestigated. This study was to investigate whether or not high flow versus low flow will affect the functional outcome of FFMT. Rat's left gracilis FFMT model was devised and the nutrient arterial inflow was modified. Twenty-four Lewis rats were divided evenly into relatively high (0.071 mL/min) and relatively low (0.031 mL/min) blood flow groups (p < 0.001). The unoperated right sides served as the controls. Cases resulting in poor function were additionally grouped as functional failure group for comparison. Regular swimming exercise was implemented at 1 month postoperatively for 3 months. Gracilis muscle functions were then evaluated. Compared groups were: control (n = 13), low blood flow (n = 10), high blood flow (n = 8), and functional failure (n = 5). The control group showed superior functional results over the experimental groups (p < 0.0001). In the experimental group, successful group showed superior over the poor function group (p < 0.01). However, there was no significant difference between the high- and low-flow groups. This is the first study to evaluate the effect of arterial inflow on the FFMT. The rate of blood flow (relatively high vs. low) has little effect on the functional outcome of transferred muscle. Survival of FFMT is the major concern while performing FFMT surgery. Arterial inflow while choosing the recipient artery is not the factor for consideration.

3D kinematic analysis of patients’ gait before and after unilateral total hip replacement

The purpose of the study was to describe changes in the kinematic parameters in the patients' gait after total hip replacement. Research group of men in the end stage of osteoarthritis indicated to the THR (n = 10; age 54.1 ± 7.5 years; weight 92.2 ± 9.6 kg; height 179.7 ± 5.9 cm). All participants underwent a total of three measurements: before surgery, 3 and 6 months after the surgery. Using the 3D kinematic analysis system, the patients' gait was recorded during each measurement session and kinematic analysis was carried out. The parameters that were monitored included the sagittal range of motion while walking in the ankle, the knee and the hip joints of the operated and the unoperated limb, and the range in the hip joint's frontal plane, the rotation of pelvis in the frontal and transverse planes, as well as the speed of walking and the walking step length. Significant increases were found in sagittal range of motion in the operated hip joint, sagittal range of motion in the ankle joint on the unoperated side and in the walking step length of the unoperated limb. During walking after a THR, the sagittal range of motion in the ankle of the unoperated limb increases. Also, the range of motion in the sagittal plane on the operated joint increases, which is related to the lengthening of the step of the unoperated lower limb.

Clinical and Radiological Results of Oxford Phase-3 Medial Unicompartmental Knee Arthroplasty.

PurposeThe aim of this retrospective study was to investigate the effectiveness of medial unicompartmental knee arthroplasty (UKA) by showing the results of the radiological and clinical outcomes of the patients.Materials and methodsSeventy-two knees of 54 patients who underwent UKA between September 2005 and March 2011 for medial knee arthritis with a minimum follow-up of six months were evaluated. Range of motion (ROM), Hospital for Special Surgery (HSS) knee score, Knee Society Score (KSS), and Oxford Knee Score (OKS) were investigated both preoperatively and postoperatively. On the other hand, Oxford radiographic evaluation criteria were used to evaluate prostheses radiologically at the final follow-up.ResultsThe average age was 53.4 years (47 to 79 years). The average follow-up time was 39.8 months (8 to 72 months). There was a significant difference between preoperative and postoperative ROM, HSS, and OKS (p<0.05). Radiologically, there was no sign of arthritis on the unoperated side of the knee or failure of prosthesis detected. Before the operation, the average clinical KSS was 63.2 and improved to 91.4 after the operation. In addition, the average functional KSS was 54.9 before the operation and improved to 86.5 after the operation. The average knee flexion degree was 109.1 before the operation and there was an improvement to 123.6 degrees after the operation. Before the operation, the average HSS score was 67.5 (range, 52 to 75) and improved to 89.9 (range, 85 to 100) at the final control examination.ConclusionThis study supports the use of Oxford Phase 3 UKA, which has excellent clinical and radiological results in patients with medial knee arthritis.

Postoperative levator function change in patients with unilateral myogenic versus aponeurotic blepharoptosis

To compare the change in levator function (LF) after levator resection in patients with unilateral myogenic (MP) and aponeurotic ptosis (AP). In a prospective study, patients of >5 years old were included from June 2015 to April 2017. Other types of ptosis, associated strabismus and previous eyelid surgery were excluded. Eyelid examination and photography were performed before and at least 6 months after surgery. Success was defined as Margin reflex distance 1 (MRD1) of within 0.5 mm of the unoperated side. All procedures (levator resection) were performed by or under supervision of one surgeon. There were 58 patients in the MP (mean age: 19.2 years) and 20 in the AP (mean age: 49.5) group with median follow up of 10 months. LF was significantly improved from 5.8 to 7.3 mm in the MP and from 11.8 to 13.6 mm in the AP group. LF improvement was not observed in 17.2% of MP and 25% of AP group (P = 0.5). Mean preoperative LF was significantly (Odd ratio=1.8) higher in patients with than without LF improvement in the MP group. It was significantly reverse in the AP group (Odd ratio=0.38). A significantly positive (r = 0.30) and negative (r=-0.72) correlations were observed between preoperative LF and LF improvement in the MP and AP groups, respectively. Success was observed in 90% of AP and 84.5% of MP group. In order of frequency, undercorrection, overcorrection, and contour abnormality were the reasons for failure. No variable significantly affected the success rate in either group. Majority of MP and AP showed postoperative LF improvement. While higher preoperative LF was significantly correlated with LF improvement in the MP, it was reverse in the AP group. Success rate was not significantly different between the groups and no factor significantly affected the success in either group.

Short to Midterm Follow-Up of Periprosthetic Bone Mineral Density after Total Hip Arthroplasty with the Ribbed Anatomic Stem.

Background Femoral bone remodeling around hip prosthesis after total hip arthroplasty (THA) is definite but unpredictable in time and place. This study aimed to investigate the implant-specific remodeling and periprosthetic bone mineral density (BMD) changes after implantation of the Ribbed anatomic cementless femoral stem. Methods After power analysis, 41 patients who had undergone primary unilateral THA with the Ribbed anatomic cementless stem were included. BMD of the seven Gruen zones was measured by dual-energy X-ray absorptiometry, and the contact, fitness, and fixation of the femoral stem and proximal femur were analyzed by X-ray. Additional clinical outcome parameters were also recorded. Results Compared with the contralateral unoperated side, significant reductions of BMD were detected in the distal zone (Gruen zone 4: 1.665±0.198 versus 1.568±0.242 g/cm2, P=0.001) and middle distal zone (Gruen zone 5: 1.660±0.209 versus 1.608±0.215 g/cm2, P=0.026) on the prosthetic side, but no significant differences in BMD were detected in other zones (Gruen zones 1, 2, 3, 6, and 7). Subgroups analyses indicated no significant correlation between periprosthetic BMD changes and clinical factors including primary disease and body mass index. Visible areas of bone ingrowth indicated solid fixation of the femoral stem and there was no case of loosening. Clinical and functional outcome scores were excellent with mean HHS of 93.13 points and mean WOMAC score of 5.20 points, and three patients described intermittent mild thigh pain at the final follow-up. Conclusions For the Ribbed femoral stem, the periprosthetic BMD was well maintained in the proximal femur, while periprosthetic BMD was significantly reduced in the distal and middle distal zones of the femur. Further clinical investigations are required to examine the efficacy of the Ribbed stem, particularly with regard to long-term survival. This trial is registered with ChiCTR1800017750.

Direct eyelid defect closure: a prospective study of functional and aesthetic outcomes.

Direct closure (DC) of eyelid defects has been retrospectively shown to give excellent outcomes. We present prospective outcome data as further evidence to promote its wider use. A consecutive, unselected, series of patients undergoing eyelid tumour resection was studied prospectively. DC was attempted at the time of biopsy in all of them. If DC proved impossible, delayed reconstruction using other techniques was later performed. Defect size, pre- and post-operative palpebral aperture (PA) measurements and the final visit patients' and surgeons' satisfaction scores for function and appearance were recorded. Seventy-three eyelids of 70 patients were studied. Mean resected specimen width was 16.4 mm (4-26 mm) in the DC group, versus 23.9 mm (11-42 mm) for other, non-DC reconstructions. Primary DC was achieved in 74% of this cohort. Mean final post-operative PA measurements in the DC group were 0.7 mm vertically (p = 0.003) and 0.8 mm horizontally (p = 0.009) less than preoperatively, but there was no statistical difference (p = 0.1) in the final horizontal measurements between the operated and un-operated sides in the DC group. DC satisfaction scores were excellent for both eyelid function and appearance. DC of eyelid defects, irrespective of per-operative PA distortion, gives excellent late post-operative outcomes. We recommend that DC, aligning the closure tension parallel to the lid margin, is attempted whenever wound margin approximation is possible in preference to alternative reconstruction techniques, regardless of any temporary PA distortion and globe displacement that this may cause. Eyelid function and appearance recover to near normal within 2 months.

Development of a rat model of patulous eustachian tube by mandibular nerve resection

ObjectivePatulous eustachian tube (PET) is currently treated using a variety of conservative or surgical approaches. To further elucidate the pathology of PET and to establish new therapies, the development of an animal model is necessary. The objective of this study was to develop a highly reproducible and sustainable rat model of PET by mandibular nerve resection. MethodsSixteen rats underwent mandibular nerve resection. Following an external incision, the main trunk of the mandibular nerve at the foramen ovale was identified in the pterygoid fossa, and its branches were resected. This surgery was performed on the right side, with the unoperated left side used as the control. To determine eustachian tube (ET) function, passive opening pressure (POP) was measured using inflation method up to Week 16 post-surgery. Changes in POP were statistically compared to the preoperative level on the operated and control sides. In addition, specimens of the ET and its surrounding tissue at Week 16 post-surgery were prepared for morphological evaluation in eight rats. ResultsOn the control side, POP did not significantly decrease across the 16 weeks post-surgery compared to the preoperative level. In contrast, on the operated side, POP was significantly decreased at Week 2 and continued to be lower than the preoperative level until at least Week 16 post-surgery. POP dropped 10% or more on the operated side examined in thirteen rats. Histologically, the medial pterygoid muscle was atrophied on the operated side mainly. ConclusionMandibular nerve resection in rats may be an effective method for generating an animal model of PET. It was suggested that this rat model may be useful for verifying new treatments for PET.

Research of a novel tissue-engineered nerve graft for sciatic nerve repair in rats

Objective To observe the effect of novel tissue engineered nerve grafts, which combined silk fibroin/collagen scaffold with a co-culture of Schwann cells (SCs) and adipose-derived stem cells (ADSCs) , to repair rat sciatic nerve defects. Methods From February, 2015 to August, 2016, the culture and purify SCs and ADSCs were isolated. And co-cultured at a ratio of 2∶1 and introduced into a silk fibroin (SF)/collagen scaffold to construct a tissue-engineered nerve conduit (TENC), which were transplanted to bridge 10 mm long sciatic nerve defects in rats. The experiment was divided randomly into 4 groups (10 rats/group): those bridged with plain SF/collagen scaffolds(Scaffold group), those bridged with TENCs (TENC group), those bridged with autografts (Autograft group) and those unoperated side (Normal group). The mechanical properties were examined using a universal testing machine(Instron 5865). Scanning electron microscopy was performed to observe the structure of the SF/collagen scaffold and the cells' growth. A series of electrophysiological examinations and morphological analyses were performed 12 weeks after surgery to evaluate the effect of the TENC on peripheral nerve regeneration. And One-way ANOVA was used to analyze the data. If the differences between groups were statistically significant, the Turkey's method was further applied for comparison. Results The plain SF/collagen scaffold showed appropriate pore size and good intercommunicating of holes. The cells were tightly attached to and partly coiled about the scaffold and exhibited either a spindle or a spherical shape. The results of the mechanical measurement revealed that the maximum and average Young’s moduli of the SF/collagen scaffold were (10.80 ± 0.30) MPa and (8.14 ± 0.20) MPa, respectively. The mechanical properties ensure that the scaffold could resist muscular contraction and maintain its shape unchanged for a considerable period of time after grafting. All rats in each group had achieved nerve defect regeneration in varying degrees. But in terms of the effect of the repaired nerve, those treated with TENC were similar to those with autologous nerve grafts but superior to those with plain SF/collagen scaffolds. Conclusion The TENC that combined silk fibroin/collagen scaffold with a co-culture of SCs and ADSCs had normal nerve-like structure, and can bridge sciatic nerve defect and promote nerve growth. Key words: Silk fibroin; Collagen; Schwann cells; Adipose-derived stem cells; Co-culture; Tissue engineered nerve

Arthroscopy of the First Metatarsophalangeal Joint

Arthroscopic treatments for the first metatarsophalangeal joint have not spread fully owing to a number of factors. First, in the common arthroscopic view, the joint is observed from above, which makes the structures difficult to grasp and the dorsal aspect of the joint difficult to visualize and treat. Second, techniques for widening the view have not yet been reported. Third, the portals necessary for observation and treatment with hallux sesamoids have not yet been established. Finally, techniques for detecting the sesamoids have not been previously reported. We have developed a method for first metatarsophalangeal joint arthroscopy by treating 14 patients with hallux rigidus and 9 patients with hallux sesamoid disorders. We report a new method that combines a variety of arthroscopic techniques. Our study has 4 novel points. First, in our arthroscopic technique, the joint can be examined from the medial side because traction is directly and horizontally applied to the great toe using an adjustable traction device with the surgeon standing on the unoperated side. The technique enables observation of the dorsal aspect of the metatarsal head and proximal phalanx and makes the structures easier to grasp. Second, the coagulator technique as an arthroscopic aid is demonstrated. Third, all aspects of the joint, including the sesamoids, can be observed through our 4 portals. Finally, techniques for detecting the sesamoids are identified. We believe our novel method will ensure that arthroscopy of the first metatarsophalangeal joint is easier than previously described methods.

Simple laryngeal suspension procedure by suturing the digastric muscle to the periosteum of the mandible in neck dissection for tongue cancer

PurposeIn this article, a simple, new laryngeal suspension procedure is described. The effect of hyoid bone suspension by suturing the digastric muscle to the periosteum of the mandible is analyzed. Materials and methodsTo elucidate the effect of hyoid bone suspension, CT scans of 26 patients who underwent ipsilateral neck dissection with primary resection of tongue cancer were retrospectively reviewed, and the distance between the hyoid bone and the mandible was measured on the operated and unoperated sides of the neck. A total of 14 patients who underwent suturing of the digastric muscle to the mandible (digastric muscle-sutured group) and the 12 patients who did not (control group) were compared. ResultsIn the digastric muscle-sutured group, the average distance between the hyoid bone and the mandible was significantly smaller on the operated side (17.8 ± 0.57 mm) than on the unoperated side (19.8 ± 0.93 mm; p < 0.05). In the control group, there was no significant difference between the operated side (21.0 ± 1.42 mm) and the unoperated side (19.7 ± 1.39 mm). The difference in the distance between the operated and unoperated sides was significantly larger in the digastric muscle-sutured group (1.97 ± 0.79 mm) than in the control group (−1.32 ± 0.61; p < 0.05). ConclusionsIt was shown for the first time that suturing of the digastric muscle to the periosteum of the mandible in neck dissection with primary resection of tongue cancer resulted in hyoid bone suspension. This simple procedure can be useful for laryngeal suspension.

Modification of the use of the extensor retinaculum for reducible distal radioulnar joint instability: technique and results.

Different surgical techniques have been described for chronic distal radioulnar joint instability: they are often complicated, quite invasive and may not be recommended for bidirectional instability. We describe a procedure using a radial-based extensor retinaculum strip and a capsular plication. This is a simple technique and less invasive than ‘anatomic’ radioulnar ligament reconstructions. We report the results of 38 patients (38 wrists) who we treated. After a minimum of 8 months we quantified the outcomes of the patients objectively by assessing ranges of motion, grip strength and clinical assessment of stability, and subjectively using questionnaires. Overall, 36 out of 38 patients were stable after surgery. The operated forearm and wrist had approximately 3° less range of motion in all planes and 3 kgf less grip strength compared with the unoperated side. The median Mayo modified wrist score was 90; the median visual analogue scale score was 2. This surgical technique appears to successfully treat patients with chronic reducible distal radioulnar joint instability. Anatomic reconstruction of both radioulnar ligaments is not always necessary.Level of evidence: IV

Bioengineered Temporomandibular Joint Disk Implants: Study Protocol for a Two-Phase Exploratory Randomized Preclinical Pilot Trial in 18 Black Merino Sheep (TEMPOJIMS).

BackgroundPreclinical trials are essential to test efficacious options to substitute the temporomandibular joint (TMJ) disk. The contemporary absence of an ideal treatment for patients with severe TMJ disorders can be related to difficulties concerning the appropriate study design to conduct preclinical trials in the TMJ field. These difficulties can be associated with the use of heterogeneous animal models, the use of the contralateral TMJ as control, the absence of rigorous randomized controlled preclinical trials with blinded outcomes assessors, and difficulties involving multidisciplinary teams.ObjectiveThis study aims to develop a new, reproducible, and effective study design for preclinical research in the TMJ domain, obtaining rigorous data related to (1) identify the impact of bilateral discectomy in black Merino sheep, (2) identify the impact of bilateral discopexy in black Merino sheep, and (3) identify the impact of three different bioengineering TMJ discs in black Merino sheep.MethodsA two-phase exploratory randomized controlled preclinical trial with blinded outcomes is proposed. In the first phase, nine sheep are randomized into three different surgical bilateral procedures: bilateral discectomy, bilateral discopexy, and sham surgery. In the second phase, nine sheep are randomized to bilaterally test three different TMJ bioengineering disk implants. The primary outcome is the histological gradation of TMJ. Secondary outcomes are imaging changes, absolute masticatory time, ruminant time per cycle, ruminant kinetics, ruminant area, and sheep weight.ResultsPrevious preclinical studies in this field have used the contralateral unoperated side as a control, different animal models ranging from mice to a canine model, with nonrandomized, nonblinded and uncontrolled study designs and limited outcomes measures. The main goal of this exploratory preclinical protocol is to set a new standard for future preclinical trials in oromaxillofacial surgery, particularly in the TMJ field, by proposing a rigorous design in black Merino sheep. The authors also intend to test the feasibility of pilot outcomes. The authors expect to increase the quality of further studies in this field and to progress in future treatment options for patients undergoing surgery for TMJ disk replacement.ConclusionsThe study has commenced, but it is too early to provide results or conclusions.

Dynamic assessment of the wrist after total wrist arthroplasty.

Our aim was to assess the outcome in patients with total wrist arthroplasty performed for end stage wrist osteoarthritis. We analysed the ranges of motion of operated and un-operated wrists using a flexible electrogoniometer during the Sollerman hand function test. We assessed grip strength with a digital dynamometer and completed patient reported outcome scores more than one year post-operatively. We reviewed 12 patients with a mean age of 64 (range 48-82) years. The flexion-extension arc was 72% and radioulnar deviation arc was 53% of the un-operated side but the total range of motion (area of circumduction) was 43% of the un-operated side and only 20% of the circumduction in age and gender-matched normal volunteers. Peak grip strength was 68% of the un-operated side. The patients reported good outcome with mean Michigan Hand Questionnaire (MHQ) scores of 56 (range 25-84) and mean Patient Evaluation Measure (PEM) scores of 39 (range 20-68). Patients completed the activities of Sollerman hand function test in twice the time (6 min) as required for a normal volunteer (2.8 min). The circumduction ellipses were narrow and central with limited radio-ulnar deviation and small mean areas of motion during activities of daily living.

Which Technique for Treatment of Chronic Thumb MCP Joint Instability? Comparison of 3 Techniques With a Mean Follow-up of 84 Months

Objective: Injuries to the thumb collateral ligament are common whose acute surgery gives good functional results. But they are often unrecognized and surgical procedures for chronic instability are still being discussed. The aim of this study was to compare retrospectively the clinical and radiological results of the 3 main treatments for chronic instability of the metacarpophalangeal (MCP) joint of the thumb to identify trends and optimize outcome. Materials and Methods: In this retrospective and monocentric study, we included all the patients operated between 2000 and 2012 from a chronic posttraumatic instability of the MCP joint of the thumb by 1 of 3 techniques: primary repair (37 cases), ligament reconstruction (14 cases), and arthrodesis (43 cases). Patients with hyperextension instability, degenerative instability, and a follow-up less than 2 years were excluded from this study. Subjective and objective results and rates of complications and recurrence were compared at end of the follow-up. Results: Sixty-seven patients were included, 55 followed up for a mean 84 months (range, 24-164 months). Whichever the procedure, all patients considered themselves improved or healed. Forty-eight patients (87.3%) were satisfied or very satisfied. The relief of pain was significantly better in the arthrodesis group. The mean Quick Disabilities of Arm, Shoulder and Hand (QuickDASH) for primary repair group were 17.4 (0-89.5), for ligament reconstruction group 25.7 (0-58.3), and for the arthrodesis group 17.8 (0-50). Pinch strength, on average of the value on the unoperated side, was 89% for primary repair group, 84% for ligament reconstruction group, and 94% for the arthrodesis group. Six of 10 ligament reconstructions had MCP joint laxity at end of follow-up. There were significantly fewer patients who considered themselves cured in the ligament reconstruction group. There were 4 failures by end of follow-up: 1 associated with primary repair, 1 with arthrodesis, and 2 with ligament reconstruction. Discussion and Conclusion: Surgery in treating chronic instability of the MCP joint of the thumb gives generally good results. Primary repair should be considered as much as possible. In contrast to literature report, ligament reconstruction does not give better results than arthrodesis.

Paper #39 - Reduced muscle degeneration and decreased fatty infiltration after rotator cuff tear in a PARP-1 knock-out mouse model

Introduction: Disturbed muscular architecture, fatty infiltration and muscular atrophy remain irreversible in chronic rotator cuff tears (RCT) even after repair. Poly-[ADP-ribose]-polymerase 1 (PARP1), a nuclear factor involved in DNA damage repair, has shown to be a key element in the up-regulation of early muscle inflammation, atrophy and fat deposition. We therefore hypothesized that the absence of PARP1 would lead to a reduction in muscular architectural damage, early inflammation, atrophy and fatty infiltration subsequent to combined tenotomy and neurotomy in a PARP1 knock-out mouse model. Methods: PARP1 knock-out (KO group) and standard wild type C57BL/6 (WT group) mice were randomly allocated into three different time points (1, 6 and 12 weeks, total n = 72). In all mice the supraspinatus (SSP) and infraspinatus (ISP) tendons of the left shoulder were detached and the SSP muscle was denervated according to a recently established model. Macroscopic muscle weight analysis, retraction documentation using macroscopic suture, magnetic resonance imaging, immunohistochemistry gene expression analysis using real time qPCR (RTqPCR) and histology were used to assess the differences in muscle architecture, early inflammation, fatty infiltration and atrophy between knock out and wild type mice in the supraspinatus muscle. Results: The SSP did retract in both groups, however; the KO muscles and tendons retracted less than the WT muscles (2.1 ± .21 mm vs 3.4 ± .41 mm;P = .02). Further assessment of muscle architecture demonstrated that the pennation angle was significantly lower in the KO groups at 6 and 12 weeks (28 ± 5 vs 36 ± 5 and 29 ± 4 vs 34 ± 3; P < .0001). Combined Tenotomy and neurotomy resulted in a significant loss of muscle mass in both groups compared to the contralateral unoperated side (KO group 62 ± 11% and WT group 52 ± 11%, P = .04) at 6 weeks. But at 12 weeks postoperatively, there was a significant increase in muscle mass to near normal levels in KO group compared to the WT group (14 ± 6% and 42 ± 7% lower muscle mass respectively; P < .0001). Immunohistochemistry revealed a significant decrease in the expression of inflammatory, apoptotic, adipogenic and muscular atrophy genes at both the 1 week and 6 weeks time points, but not at 12 weeks in the KO group compared to the WT group. This was confirmed by histology. Discussion: Our study is the first to show that knocking out PARP1 leads to decreased loss of muscle architecture, early inflammation, fatty infiltration and atrophy after combined tenotomy and neurotomy of the rotator cuff muscle. Although KO and WT mice developed severe atrophy and fatty infiltration 6 weeks after surgery, the muscles of the KO mice regenerated to almost normal size after 12 weeks. We conclude that PARP1 has an influence on the muscular deterioration after RCT.

Restoration of Sensibility Following Intentional Infra-Orbital Nerve Transection in Unilateral Cleft Lip Repair

INTRODUCTION: Repair of the wide cleft lip in which presurgical orthopedics is not used can present challenges to achieving a tension-free reconstruction. In order to limit tension during wide cleft lip repair, we routinely sacrifice the infraorbital nerve during mobilization of the lateral lip elements. Prior studies in pediatric hand trauma demonstrate return of sensibility in the absence of nerve repair through the phenomenon of adjacent neurotization. Faivre et al demonstrated good return of light touch sensation in all patients with Semmes-Weinstein monofilaments in the 2.83 to 3.83 range.1 All patients in that study demonstrated return of discriminatory sensation and excellent functional results. The aim of this study is to evaluate the medium-term sensibility outcomes after infraorbital nerve transection during radical cheek dissection at the time of wide cleft lip repairs. MATERIALS AND METHODS: A 3-year single-surgeon retrospective review of patients undergoing unilateral cleft lip repair with radical cheek dissection was performed. Radical cheek dissection was defined as supraperiosteal dissection across the entire face of the maxilla as far superior as the infraorbital rim, transecting the infraorbital nerve. Recorded variables include age at the time of sensory exam, other diagnoses, and results of Semmes-Weinstein monofilament testing (4.31, 3.61, and 2.83 levels) on the side of surgery and the unoperated side.2 RESULTS: Fifty-seven patients underwent unilateral cleft lip repair during the study period and 9 patients met inclusion criteria (Table 1). The mean age at the time of sensory examination was 4.9 years (range 3.9 to 6.2 years). Nine patients had intact lip sensibility on the operated side when stimulated with the finest Semmes-Weinstein monofilament (2.83). None of the patients examined reported a subjective change in sensation across the upper lip. All patients reported an elicited sensory response on the operated side when stimulated with all tested filament levels. There were no patients that had a difference in sensibility compared to the control side (p = 1.00).Table 1: Patient Summary.CONCLUSIONS: Transection of the infraorbital nerve during primary cleft lip repair has no detrimental effect on upper lip sensibility. There should be limited concern for sacrifice of upper lip sensibility during lateral lip mobilization. Prospective, randomized analysis would be required to compare the potential benefit to outcomes that the described technique may offer.

Corneal hypoesthesia with normal sub-basal nerve density following surgery for trigeminal neuralgia.

To evaluate the corneal sub-basal nerve plexus in patients presenting with hypoesthesia following surgery for trigeminal neuralgia. Twenty-one patients who had unilateral medically uncontrolled trigeminal neuralgia and underwent ipsilateral surgery from 2006 to 2012 were included. Of these, 10 had microvascular decompression (MVD group) and 11 had balloon compression of the trigeminal ganglion (BC group). Slit lamp examination, Cochet-Bonnet aesthesiometery and in vivo confocal microscopy were carried out on both eyes of each patient. Nerve density data were statistically analysed. Corneal sensations and sub-basal nerve densities in MVD group were normal and equal in both the operated and unoperated sides, indicating that there was no intra-operative damage of the ophthalmic division of the trigeminal nerve (V1). However, those in BC group, despite having significantly reduced corneal sensations on the operated side (p=0.007), did not demonstrate any significant difference in their sub-basal nerve densities (p=0.477). No patient had any ocular symptoms. This study supports the hypothesis that complete ganglionic damage and/or postganglionic damage of V1 results in corneal hypoesthesia and neurotrophic keratitis, but partial ganglionic or preganglionic damage would preserve trophic function despite hypoesthesia and not result in clinically significant symptoms or signs of neurotrophic keratitis. The trophic and sensory functions of V1 are therefore independent and can be dissociated by disease or injury.

Outcome of unilateral ankle arthrodesis and total ankle replacement in terms of bilateral gait mechanics

Previous studies assessed the outcome of ankle arthrodesis (AA) and total ankle replacement (TAR) surgeries; however, the extent of postoperative recovery towards bilateral gait mechanics (BGM) is unknown. We evaluated the outcome of the two surgeries at least 2 years post rehabilitation, focusing on BGM. 36 participants, including 12 AA patients, 12 TAR patients, and 12 controls were included. Gait assessment over 50 m distance was performed utilizing pressure insoles and 3D inertial sensors, following which an intraindividual comparison was performed. Most spatiotemporal and kinematic parameters in the TAR group were indicative of good gait symmetry, while the AA group presented significant differences. Plantar pressure symmetry among the AA group was also significantly distorted. Abnormality in biomechanical behavior of the AA unoperated, contralateral foot was observed. In summary, our results indicate an altered BGM in AA patients, whereas a relatively fully recovered BGM is observed in TAR patients, despite the quantitative differences in several parameters when compared to a healthy population. Our study supports a biomechanical assessment and rehabilitation of both operated and unoperated sides after major surgeries for ankle osteoarthrosis.

Hip resurfacing using a modified lateral approach with limited splitting of the gluteus medius muscle results in significant impairment of hip abductor strength

A lateral, transgluteal approach for hip resurfacing carries the risk of approach-related weakening of the hip abductors due to unsuccessful re-adaptation of the gluteal muscles to the greater trochanter or to injury to the inferior nerve branch of the superior gluteal nerve. We investigated whether hip resurfacing using a soft tissue-sparing, modified transgluteal approach with limited cranial splitting of the gluteus medius muscle reduces hip abductor strength and the risk of approach-related injury to the superior gluteal nerve. Thirty-one patients (14 female, 17 male; mean age 53.5 ± 5.2 years) underwent hip resurfacing using a modified transgluteal approach with limited cranial splitting of the gluteus medius muscle. Nerve conduction signals were measured by surface electromyography (EMG), hip abductor strength by isokinetic testing a mean 36.2 months (± 11 mos) after surgery. The unoperated side was used as control. Surface EMG disclosed no neural lesions of the inferior branch of the superior gluteal nerve. Isokinetics revealed a significant reduction in muscle strength on the operated versus the contralateral side. Even a limited incision of the gluteus medius muscle resulted in significant impairment of hip abductor strength 2.5 years after surgery.