Bony Bed Research Articles

Snapping Biceps Femoris Repair: A Rare Cause of Lateral Knee Pain

Background: Snapping biceps femoris syndrome (SFS) represents a rare clinical entity in which the biceps femoris subluxates over the fibular head in deep flexion. Two primary pathophysiologies have been described including a prominent or abnormal fibular head morphology. Others have implicated an anomalous biceps femoris insertion. The diagnosis is made clinically, with operative and nonoperative intervention strategies available for treatment. Indications: SFS often results in audible snapping and associated pain at the lateral fibular head. When recalcitrant to nonoperative management, surgical intervention can lead to resolution of symptoms. We present the case of a college-aged male who has bilateral symptoms, worse on the right, which have resulted in significant activity modification and daily discomfort recalcitrant to anti-inflammatory medication and physical therapy. Technique Description: The patient was placed supine on the operating room table with an ipsilateral bump under the hip to assist in exposure of the lateral aspect of the knee. Examination under anesthesia (EUA) confirmed the snapping biceps femoris. A lateral approach to the knee and a common peroneal neurolysis was performed. The biceps femoris insertional anatomy was examined for anomalous tendon insertion or insertional tearing. The prominent fibular head was exposed and resected, with careful attention not to disrupt the lateral collateral ligament or popliteofibular ligament insertion sites. The biceps femoris was then repaired to the prepared bony bed of the fibula with one double-loaded suture anchor. Repeat EUA confirmed complete resolution of snapping even with maximal internal rotation of the tibia; this was carefully examined again with the tourniquet deflated to ensure its compressive effect was not partially responsible for the resolution. Results: Published data pertaining to SFS is limited to case reports and small case series. With appropriate indications, surgical intervention yields promising results with a high percentage of patients returning to prior level of activity or prior participation level in sport. Discussion/Conclusion: SFS can be diagnosed with a careful clinical assessment. When recalcitrant to nonoperative management, it is effectively treated with surgical intervention to restore normal fibular anatomy, and prevent recurrent instability and persistent pain. The presented technique allows for appropriate management of these rare injuries. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Preparing the Bony Bed: Socket Grafting with TCP Bone Graft, Innovations for Tomorrow's Radiant Smiles

Preparing the Bony Bed: Socket Grafting with TCP Bone Graft, Innovations for Tomorrow's Radiant Smiles

A Case Report and Functional Outcome in Bilateral Osteochondritis Dissecans in the Knee which was Operated Arthroscopically

Definition  Osteochondritis Dissecans (OCD) is a disorder of subchondral bone, which secondarily affects the overlying articular cartilage.  In OCD, an area of subchondral bone becomes necrotic, resulting in a loss of structural support for the overlying articular cartilage. This process leads to degeneration and fragmentation of the articular cartilage and underlying bone.  In the absence of treatment or spontaneous regression, the osteochondral fragment gradually separates from its bony bed, eventually forming a loose body.

Aesthetic Reconstruction of an Old Burr Hole Defect Using a Cancellous Bone Chip and a Porous Polyethylene Implant.

Burr hole trephination is a minimally invasive procedure but can leave a depressed scar at the surgical site. Various materials have been studied to fill such defects; however, to the best of our knowledge, there are no reports of reconstructing old, depressed scars from burr hole surgery. This report presents a patient with depressed scarring near the anterior hairline of the frontal bone on both sides due to burr hole trephination for a subdural hematoma 27 years prior. Computed tomography scans revealed bony defects under the scar. Reconstruction of the bony defect was performed by debriding the bony bed, filling it with hydrated alloplastic cancellous bone, and covering it with a porous SynPOR polyethylene titanium-reinforced implant. During 1 year of follow-up, the reconstruction was maintained without complications. The patient was satisfied with the esthetic outcome. Thus, old bony defects can be repaired using the appropriate materials and techniques.

Anterior Cruciate Ligament Reconstruction With Transtibial Medial Meniscus Root Repair

Background: The incidence of anterior cruciate ligament (ACL) injuries has rapidly increased. Patients with ACL injuries frequently present with concomitant meniscal pathologies. Posterior medial meniscal root tears (PMMR) are less commonly seen with acute ACL injuries as compared with lateral tears and are often degenerative in nature or more rarely in an acute setting. Clinical studies have demonstrated medial meniscal deficiency to be a significant risk factor for graft failure and poor postoperative clinical outcomes. As such, given its demonstrated efficacy, there has been growing interest in transtibial meniscal repair mechanisms in combination with an ACL reconstruction as a potential solution to this challenging pathology. Indication: Patients are indicated for surgery when presenting with symptomatic ACL deficiency verified on provocative testing and advanced imaging and objective insufficiency of the medial meniscal root. Contraindications for this procedure include advanced osteoarthritis (Kellgren–Lawrence grade ≥3) on weight-bearing x-rays, age <50 years, and body mass index (BMI) > 30 as well as poor-quality meniscal tissue and unrepairable chondral defects. Technique Description: The ACL stump is debrided and a burr hole is created. A femoral aiming guide is used to drill the femoral tunnel. Following medial collateral ligament (MCL) release, a healing bony bed is prepared with a curette and shaver at the anatomic tibial footprint. An aiming device is then used through the anterior medial portal to create 2 transosseous tibial tunnels. A vertical mattress suture and simple suture are placed through the meniscal root, shuttled through the posterior and anterior transosseous tunnels, respectively. The tibial ACL tunnel is placed using a standard guide to avoid tunnel convergence with the root tunnels and prevent graft tunnel mismatch. After graft passage, interference screws are inserted while maintaining graft tension. The sutures are then tied over a cortical button over the tibia. Results: Within 2 years postoperatively, patients are expected to have improved overall knee-specific quality of life, reduced pain, and a successful return to activities with low rates of graft failure. Discussion/Conclusion: Recent advancements in our understanding of the relationship between the medial meniscus and the ACL should prompt surgeons to continue considering such combined treatments in indicated patients. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Arthroscopic Repair of a “Floating” Posterior Inferior Glenohumeral Ligament

Background: Combined posterior glenoid labrum lesions with posterior humeral avulsion of the glenohumeral ligament, also known as the “floating” posterior inferior glenohumeral ligament (PIGL), occur infrequently. These combined lesions are frequently missed on magnetic resonance imaging in the workup of posterior shoulder instability. Correct identification of the “floating” PIGL lesion allows for appropriate preoperative planning and treatment to decrease the risk of recurrent posterior shoulder instability. Indications: A “floating” PIGL lesion is a cause of posterior shoulder instability and demonstrates increased translation when compared with isolated labral lesions. Surgical repair of an acute “floating” PIGL lesion with concomitant superior labral tear is described. Technique Description: The patient is placed in the lateral decubitus position. Standard posterior and anterior portals are created. In this case, a superior labral tear with anterior labral tear extension was also identified and repaired. The posterior labrum was repaired prior to the posterior humeral avulsion of the glenohumeral ligament (HAGL). The torn posterior labrum is mobilized and glenoid bony bed prepared. Short, 2.9-mm biocomposite knotless suture anchors loaded with suture tape are used for labral fixation. A 70° arthroscope is used to visualize the posterior HAGL from the anterior cannula and an additional posterior inferior portal established. The footprint of PIGL on the humerus is identified, debrided, and two 3.0-mm anchors loaded with suture placed. The sutures are passed through the capsule and PIGL and tied in a mattress pattern external to the capsule and ligament. The posterior portals are closed with nonabsorbable suture. Results: While few outcomes are described in the literature for the “floating” PIGL, the literature suggests good outcomes following surgical repair. Conclusion: The “floating” PIGL lesion is a rare cause of posterior shoulder instability. It is important to perform a thorough evaluation for concomitant pathology in patients with posterior shoulder instability as multiple structures can be injured. Arthroscopic repair of the posterior labrum and posterior humeral avulsion of the glenohumeral ligament can be performed to restore posterior stability to the shoulder in the setting of a “floating” PIGL.

Changes in the Area Adjacent to the Internal Receiver-Stimulator of Cochlear Implant: A Retrospective Study.

In some patients with cochlear implants, bony resorption at the internal receiver- stimulator site can be observed on postoperative computed tomography. Therefore, it is essential to elucidate the effects of the internal receiver-stimulator on the scalp and bony bed over time. We aimed to evaluate how the internal receiver-stimulator of a cochlear implant device changed the thickness of the surrounding scalp and skull over time using computed tomography. This retrospective study evaluated patients who underwent cochlear implantation and received two computed tomography scans postoperatively for different indications at a tertiary referral centre. The main outcomes were scalp thickness and bony bed depth. Fourteen ears were included in this study. There was very good inter-rater reliability among the two readers who evaluated the computed tomography of the included patients, with a Cronbach's alpha of 0.94. The mean scalp thickness over the internal receiver-stimulator was 6.02 (+/-2.4) mm in the first scan and decreased with no significant change to 5.62 mm (+/-1.64) in the second scan (p = 0.59, paired t-test). The mean depth of the bony bed increased significantly from 1.39 mm (+/-0.93) to 2.62 mm (+/-1.24) (p = 0.03). There was no change in the thickness of the scalp overlying the internal receiver-stimulator indicating that the scalp was more resistant than the bony skull to the tensile pressure exerted by the internal receiver-stimulator. In contrast, the bony bed depth of the internal receiver-stimulator increased over time. This can result in decreased internal receiver-stimulator protrusion and decreased risk of device displacement and migration.

Efficacy of Gas Combination Cryotherapy in the Management of Odontogenic Keratocyst of the Maxilla and Mandible: A Pilot Study.

The aim of this study was to evaluate outcome of management of odontogenic keratocyst (OKC) using gas combination cryotherapy (GCC). GCC is a treatment modality where cyst enucleation is followed by applying an adjuvant agent, a spray containing propane, butane and isobutene gas onto the bony bed. This was a prospective interventional study which included patients with radiographic and histopathologic evidence of OKC. All patients underwent enucleation of the cysts followed by spraying of the bony cavity with "ENDOFROST ™"(commercially available agent for GCC). Patients were periodically reviewed and the presence of wound dehiscence, infection and neurosensory deficit was noted. After 15months, a CBCT was taken to assess the amount of bone formation, the presence of any pathologic fracture or recurrence. Comparison of the preoperative and the postoperative size of the defect was also assessed. A total of 10 patients were included in the study of which only 2 presented with neurosensory deficit in the post-op period. One patient of the two patients recovered completely within 12months, while the other recovered within 15months. There was no evidence of any patient developing infection, wound dehiscence, recurrence or pathologic fracture. The results of the study show that enucleation followed by GCC is a safe, effective and low-cost therapy for the management of OKC.

Cochlear Implant Fixation Techniques: A Systematic Review of the Literature.

Given the lack of consensus on fixation techniques of the cochlear implant, this review aims to create an up-to-date overview of intra- and postoperative complications, focusing on migration of the internal receiver/stimulator (R/S) device and the electrode array. On June 29, 2020 we conducted a search in PubMed, Embase, Cochrane, Web of Science, and CINAHL. Keywords were "Cochlear implant," "complication," "migration," and synonyms. Studies were considered if: 1) the adult study population consisted of ≥ 10 patients, 2) the R/S device was fixated using the bony well or tight subperiostal pocket technique without bone-anchoring sutures or screws on the implant, and 3) migration of the R/S device or displacement of the electrode array were described as outcomes. Study characteristics, interventions, follow-up, and outcomes were extracted. For critical appraisal, an adapted version of the Newcastle-Ottawa quality assessment scale for cohort studies was used. Seven studies were included (n = 430 patients). Migration of the R/S device was reported by three studies. Two studies applying the tight pocket technique reported migration rates ranging from 9.0 to 69.2%. One study using the bony bed technique reported migration of 100%, with an average of 2.5 mm. All studies lacked the required standard for comparability, assessment of outcome, and follow-up. There is currently no evidence of a difference between the bony bed- and tight pocket fixation technique, regarding migration of the R/S device or the electrode array, in adult patients.

Posterior Humeral Avulsion of the Glenohumeral Ligament: A Rare and Nonspecific Injury

Posterior Humeral Avulsion of the Glenohumeral Ligament: A Rare and Nonspecific Injury

Osteochondritis Dissecans of the Knee: Arthroscopic Suture Anchor Fixation

Osteochondritis dissecans (OCD) is a subchondral bone abnormality, in which subchondral bone and the overlying articular cartilage detach from the bony bed. Multiple techniques for OCD fixation have been described, including metallic, bioabsorbable implants and biological fixation. We describe a surgical technique for OCD lesions including bony bed preparation with curettage and microfracture, anatomic reduction, and fixation using a suture anchor to provide stability and healing of the lesion.

Preoperative assessment of medial acetabular wall bone stock in dysplastic deformation

Acetabular reconstruction remains to be one of the crucial aspects of total hip replacament in developmental dysplasia of the hip (DDH) that provides endoprosthesis’ long-term stability and general success of the operation. Among the parameters that influence surgical technique of acetabular reconstruction, medial wall bone stock of the endoprosthesis’ bed zone should be taken into consideration. Purpose of the work to assess medial wall bone stock in the site of acetabular component’s bony bed in normal and dysplastic deformed hips and to define correlation with indices of sphericity and sectoral deficiency of the acetabulum based on MSCT-morphomerty. Materials and methods. A complex comparative MSCT-mophometric investigation of 32 normal hips and 65 hips with DDH (Crowe I – 26 hips (40.0 %), Crowe II – 23 hips (35.4 %), Crowe III – 16 hips (24.6 %)) was performed. There were assessed width of the medial wall bone stock in the projection of the crucial ligament’s and acetabular component’s bony beds according to the proposed method; their correlation with indices of femoral head’s cranial migration and acetabular horizontal sphericity angle. Results. It has been revealed that measurements in he site of the crucial ligament’s bony bed based on pelvic images obtained by a conventional biplanar X-ray remains to be biased and doesn’t correspond to true width of medial acetabular wall bone stock. Absolute width of the medial acetabular wall in sites of the crucial ligament’s / acetabular component’s bony beds carried out through the special MSCT-recontruction methodic was defined as: 4.3 mm [3.3; 4.8]/7,2 mm [6.2; 7.8] for normal hips, 9.95 mm [7.5; 11.6]/11.85 mm [9.8; 13.5] for Crowe I hips,15 mm [11.7; 17.3]/15,7 mm [13,5; 17,3] for Crowe II hips and 15.45 mm [13.7; 19.8]/16.05 mm [12.8; 20.2] for Crowe III hips, respectively. Correlations between medial acetabular wall bone stock in site of acetabular component’s bony bed and indices of femoral head’s cranial migration and acetabular horizontal sphericity angle were defined as: r = 0.36 (P = 0.006); r = 0.36 (P = 0.007), respectively. Conclusions. Weak correlation of medial acetabular wall bone stock with indices of acetabular sphericity and sectoral deficiency requires the necessity of independent evaluation of this index during preoperative planning. Due to the impossibility of the index assessment based on the conventional pelvic X-ray, application of elaborated MSCT-morphometric methodic seems to be clinically valuable and should be applied during preoperative examination of patients with DDH.

Application of a paste-type acellular dermal matrix for coverage of chronic ulcerative wounds.

BackgroundChronic wounds occur due to failure of the normal healing process, associated with a lack of deposition of cellular components and a suitable microenvironment such as the extracellular matrix (ECM). Acellular dermal matrix (ADM) is viewed as an ECM substitute, and a paste-type ADM has recently been introduced. We hypothesized that CGPaste, an injectable paste-type ADM, could serve as a scaffold and promote wound healing.MethodsWe retrospectively studied seven patients in whom CGPaste was applied between 2017 and 2018, who had pressure ulcers, necrotizing fasciitis, diabetic foot ulcers, traumatic defects, and osteomyelitis. The goal of applying CGPaste was to achieve complete wound healing with re-epithelialization or growth of granulation tissue, depending upon the wound bed status. CGPaste was injected based on the wound size along with the application of a dressing.ResultsFour of the seven patients showed granulation tissue on their wound bed, while the other three patients had a bony wound bed. The mean wound area was 453.57 mm2 and the depth was 10.71 mm. Wound healing occurred in five of the seven patients (71.43%). The mean duration of complete healing was 2.4 weeks. Two patients showed failure due to paste absorption (29.57%); these patients had wound beds comprising bone with relatively large and deep wounds (40×30 and 30×20 mm2 in area and 15 and 10 mm in depth).ConclusionsCGPaste is an effective option for coverage of small and deep chronic wounds for which a flap operation or skin grafting is unfeasible.

Carbon Dioxide Insufflation of the Knee in the Treatment of Full-Thickness Chondral Defects With Micronized Human Articular Cartilage

BioCartilage (BC) is dehydrated, minced human hyaline articular cartilage that was developed as an adjunct to microfracture surgery to help stimulate the bone marrow and stem cells to form hyaline-like tissue in full-thickness chondral defects. The minced pieces of BC require a dry environment for application and can easily be disrupted by residual moisture of saline solution in the surrounding tissues. We present a technique of carbon dioxide insufflation during knee arthroscopy as a means of maintaining a dry environment for preparation of the bony bed during BC augmentation of microfracture surgery. This technique is safe and provides more than adequate visualization, as well as a dry environment, to make the arthroscopic application of BC significantly more efficient.

The use of the microbial and entomological data for the diagnostics of prescription of death coming

The objective of the present study was to demonstrate the possibility of the diagnostics of prescription of death coming (PDC) based on the results of the studies with the application of the entomological and microbiological methods. The entomological materials included larvae of two dipteran species Stearibia nigriceps (Piophilidae) and Fannia vesparia (Fanniidae) collected from bone tissue fragments and the bony bed. The detailed investigation of the succession of necrophilic insects taking place in the course of decomposition of organic matter and the development of the preimaginal stages of the dipterans made it possible to determine the duration of the period during which the corpse remained in the ambient environment. The microbiological studies made it possible to determine the composition of necrobiome of the bone remains. It included, among other things, the association of soil bacterial forms belonging to the orders Actinomycetales, Pseudomonadales, and Aeromonadales in the combination with the fungi of the order Endomycetales. The enteral microorganisms that trigger putrefaction at the early stages of corpse decomposition were totally absent in the remains that hosted soil microorganisms destroying the hard tissues. The predominance of Actinobacteria in the samples of bone remains gave evidence of active disintegration of the skeletal tissues by the bacterial species inhabiting the local soil milieu. The study demonstrated that the results of the analysis of the microbial constituent of the washouts from the surfaces of the skull and the left upper arm bone of the human corpse were consistent with the conclusion about the prescription of death coming based on the entomological data. It is agued that the development of the methods for the diagnostics of prescription of death coming, including those to be used for the examination of the skeletonized corpses, based on the results of the entomological and microbiological investigations has good prospects as an area of research in the field of forensic medicine.

Double-Row Suture Anchor Repair of Posterolateral Corner Avulsion Fractures

Posterolateral corner avulsion fractures are a rare variant of ligamentous knee injury primarily described in the skeletally immature population. Injury is often related to a direct varus moment placed on the knee during sporting activities. Various treatment strategies have been discussed ranging from nonoperative management, to excision of the bony fragment, to primary repair with screws or suture. The described technique is a means for achieving fixation of the bony avulsion using principles familiar to double-row transosseous equivalent rotator cuff repair. Proximal anchors are placed in the epiphysis, and sutures are passed in horizontal mattress fashion. Once tied, the limbs of these same sutures are then passed to more distal anchors. Remaining eyelet sutures can be used to manage peripheral tissue. The final repair provides anatomic reduction and compression of the fragment to its bony bed with minimal extracortical hardware prominence and no violation of the physis. Risks include potential for physeal injury or chondral damage to the lateral femoral condyle through aberrant anchor placement. Postoperative care includes toe-touch weight-bearing restrictions and range of motion restrictions of 0°-90° in a hinged brace for 6 weeks followed by gradual return to activity.

セメントTHAのソケット固定手技の工夫: 股臼骨温存・骨母床再建手技

セメントTHAのソケット固定手技の工夫: 股臼骨温存・骨母床再建手技

A topology-based method to mitigate the dosimetric uncertainty caused by the positional variation of the boost volume in breast conservative radiotherapy

BackgroundTo improve local control rate in patients with breast cancer receiving adjuvant radiotherapy after breast conservative surgery, additional boost dose to the tumor bed could be delivered simultaneously via the simultaneous integrated boost (SIB) modulated technique. However, the position of tumor bed kept changing during the treatment course as the treatment position was aligned to bony anatomy. This study aimed to analyze the positional uncertainties between bony anatomy and tumor bed, and a topology-based approach was derived to stratify patients with high variation in tumor bed localization.MethodsSixty patients with early-stage breast cancer or ductal carcinoma in situ were enrolled. All received adjuvant whole breast radiotherapy with or without local boost via SIB technique. The delineation of tumor bed was defined by incorporating the anatomy of seroma, adjacent surgical clips, and any architectural distortion on computed tomography simulation. A total of 1740 on-board images were retrospectively analyzed. Positional uncertainty of tumor bed was assessed by four components: namely systematic error (SE), and random error (RE), through anterior-posterior (AP), cranial-caudal (CC), left-right (LR) directions and couch rotation (CR). Age, tumor location, and body-mass factors including volume of breast, volume of tumor bed, breast thickness, and body mass index (BMI) were analyzed for their predictive role. The appropriate margin to accommodate the positional uncertainty of the boost volume was assessed, and the new plans with this margin for the tumor bed was designed as the high risk planning target volume (PTV-H) were created retrospectively to evaluate the impact on organs at risk.ResultsIn univariate analysis, a larger breast thickness, larger breast volume, higher BMI, and different tumor locations correlated with a greater positional uncertainty of tumor bed. However, BMI was the only factor associated with displacements of surgical clips in the multivariate analysis and patients with higher BMI were stratified as high variation group. When image guidance was aligned to bony structures, the SE and RE of clip displacement were consistently larger in the high variation group. The corresponding PTV-H margins for the high- and low-variation groups were 7, 10, 10 mm and 4, 9, 6 mm in AP, CC, LR directions, respectively. The heart dose between the two plans was not significantly different, whereas the dosimetric parameters for the ipsilateral lung were generally higher in the new plans.ConclusionsIn patients with breast cancer receiving adjuvant radiotherapy, a higher BMI is associated with a greater positional uncertainty of the boost tumor volume. More generous margin should be considered and it can be safely applied through proper design of beam arrangement with advanced treatment techniques.

Optimisation of BMP-2 dosage for the osseointegration of porous titanium implants in an ovine model.

In clinical orthopaedics, total joint replacements and spinal fusions are routine undertakings. Many of the implicated patients suffer from osteoporosis, severe arthrosis or osteopaenia. In individuals thus afflicted, the bony bed lacks the mechanical stability that is a requisite for a firm anchorage of the implant and its functional competence. To promote the bony bondage of an implant it is necessary to induce neo-ossification by the introduction of an osteogenic agent, such as bone morphogenetic protein 2 (BMP-2). Since this growth factor is generally applied in a free form and at high dosages to maximise its osteogenicity, untoward side effects frequently ensue. We hypothesise that the administration of BMP-2 using a suitable delivery vehicle, and its gradual, low dose release therefrom in a cell-mediated manner, would avert the triggering of undesired side effects and enhance its efficacy. To test this postulate, implants of porous titanium were coated with a layer of calcium phosphate into which BMP-2 was biomimetically incorporated at dosages ranging from 0.8 to 500 µg/g of coating material (delivery system) prior to their surgical placement in the tibiae of adult sheep. The volume and the surface area of newly-formed bone were evaluated histomorphometrically after 3 and 6 weeks. The highest values were achieved using BMP-2 dosages of 20 to 100 µg/g of coating: The deposition of bone was confined to the immediate vicinity of the implant and was observed deep within the interstices of its meshwork, to the walls of which it bonded well. The findings of the study attest to the validity of our hypothesis.

Comparison of fixation properties between coil-type and screw-type anchors for rotator cuff repair: A virtual pullout testing using 3-dimensional finite element method.

Pullout of inserted anchor constitutes one of the pathomechanisms of re-tearing after rotator cuff repair. The purpose of the present study was to investigate the fixation properties of suture anchors using 3-dimensional finite element method. The computer models of three types of anchors (TwinFix Ti, HEALICOIL PK and HEALICOIL RG) were inserted into the isotropic cube model that simulated cancellous bone. In the virtual pullout testing, a tensile load (500N) along the long axis of the inserted anchor was applied to the site of suture thread attachment to simulate a traction force. The distribution of von Mises equivalent stress, the failure patterns of elements inside the cube and the anchor displacement were compared among the three anchors. In TwinFix Ti, the highest stress concentration was seen around the anchor threads close to the surface of the cube, which caused element failure at this site. On the other hand, both HEALICOIL PK and HEALICOIL RG demonstrated a high stress concentration as well as element failure around the anchor tip. Comparing the anchor displacement, HEALICOIL RG showed the smallest displacement among the three anchors. The tensile loads that required a 0.1-mm displacement for TwinFix Ti, HEALICOIL PK and HEALICOIL RG were 400N, 370N, and greater than 500N, respectively. The bony structures close to the footprint surface may be damaged during surgery due to preparation for the bony bed as well as the insertion of anchors. Thus, we assumed that HEALICOIL RG represented the best initial fixation properties among the three anchors tested. Virtual pullout testing using 3-dimensional finite element method could reveal the detailed biomechanical characteristics of each suture anchor, which would be important for shoulder surgeons to improve the clinical outcomes of rotator cuff repair.