Staple Fixation Research Articles

Assessment of chronic pain syndrome after laparoscopic transabdominal preperitoneal plastic surgery in patients with inguinal hernia

Aim. To assess pain syndrome in patients with inguinal hernia after laparoscopic transabdominal preperitoneal (TAPP) plastic surgery. Materials and methods. The study involved 58 patients with unilateral Nyhus type 2 and 3 inguinal hernia. The patients underwent laparoscopic TAPP plastic surgery using a mesh implant that was not fixed independently. According to the method of graft fixation, the patients were divided into two groups. In the first patient group, staple fixation of the mesh was applied – 28 (48.3 %), the second group – 30 (51.7 %) patients without mesh fixation. Patients with a history of surgical interventions on the abdominal cavity and pelvis, complicated or recurrent inguinal hernia were excluded from the study. Pain syndrome was assessed using the visual analog scale and an independent survey during postoperative follow-ups of the patients every three months for two years. Results. In the assessment of postoperative pain in the first patient group, moderate pain intensity was noted, and it was minimal in the second group, p < 0.001. 9 (32.1 %) patients who underwent mesh implant fixation required opioid analgesics, compared with 4 (13.3 %) patients who did not undergo fixation, p = 0.043. At the first examination, chronic pain was detected in 6 (21.4 %) patients of the first group and in 3 (10.0 %) patients of the second group. During a year, pain syndrome gradually disappeared. After 9 months, pain was reported by 4 (14.3 %) patients in the group with mesh fixation and by 1 (3.3 %) patient without fixation. At the 6th examination in the first group, 2 (7.1 %) patients reported pain; 1 (3.6 %) patient underwent Lichtenstein hernioplasty due to recurrent, increasing acute pain. Conclusions. Laparoscopic TAPP plastic surgery without graft fixation shows a lower possibility of pain syndrome development than with mesh implant fixation. In the case of chronic pain syndrome development following the TAPP technique without mesh fixation, the general condition of patients improves more quickly.

Biomechanical comparison of bone staple fixation methods with suture material for median sternotomy closure using 3D-printed bone models

ABSTRACT Aim To compare the biomechanical properties of three different sternal closure techniques in a 3D-printed bone model of a sternum from a 30-kg dog. Methods Median sternotomy was performed on a total of 90 three-dimensional (3D) copies of a polycarbonate (PC) model of a sternum, generated from the CT images of the sternum of a 30-kg German Shepherd dog. Three different methods were used to repair the sternotomies: polydioxanone suture (group PDS, n = 30), stainless steel bone staples (group SS, n = 30), and nitinol bone staples (group NS, n = 30). Each repair method was tested by applying tensile force in one of three ways (longitudinally, laterally, or torsionally) resulting in a sample size of n = 10 for each repair method-loading combination. In all experiments, the loads at 1-mm and 2-mm gap formation, failure, and the displacement at the failure point were measured. Results In lateral distraction and longitudinal shear tests, NS and SS staple repairs required application of significantly greater force than PDS across all displacement criteria (1 and 2 mm). NS exhibited significantly greater failure load than PDS. In torsion tests, NS required significantly greater application of force compared to SS or PDS at all displacement criteria (1 and 2 mm) and exhibited a greater failure load than PDS. In terms of displacement at failure point, PDS suture showed more displacement than SS or NS across all experiments (laterally, longitudinally, torsionally). Conclusions In this study, bone staples were mechanically superior to PDS suture in median sternotomy closure using 3D-printed bone model in terms of 1-mm, 2-mm displacement loads, and displacement at failure. NS had a higher failure load than PDS under lateral, longitudinal, and torsional distraction. Clinical relevance These study results imply that bone staples can be considered as an alternative surgical method for median sternotomy closure in dogs.

Cannulated screws versus nitinol staple for tarsometatarsal fusion: A cadaveric biomechanical comparison model

BackgroundThe objective of this study was to evaluate the biomechanical stability of a medially placed nitinol staple compared to two crossed-screws in the first TMT-1 joint fusion in a cadaveric cyclic loading model. MethodsSeven matched pairs (N = 7) of lower limb cadaveric specimens were utilized. TMT-1 joints from each donor were fixed with a medially placed nitinol staple or dorsally placed two 3.5 mm partially threaded cannulated crossed-screws. Specimens were tested in a 4-point bending setting with increasing cyclic forces. ResultsThe mean plantar gapping was not significantly different between the two groups at any loading stage below 200 N. Specimens fixed with a nitinol staple failed at a mean load of 305 ± 57 N. Conversely, those fixed with crossed-screws failed at 373 ± 86 N. (P = .09). ConclusionThere was no statistical difference between a medially placed nitinol staple and dorsally placed crossed-screws in failure loads and plantar gapping under cyclic loads at the TMT-1 joint, however, the staple fixation was much more variable. Level of evidenceLevel V, basic science study, biomechanics

Postoperative pain in transabdominal preperitoneal laparoscopic hernia repair with staple fixation versus self-fixation mesh

BackgroundThe mesh fixation method is one of the multiple factors associated with chronic postoperative pain in inguinal hernia surgery. The aim of this study is to evaluate postoperative pain associated with the two available fixation strategies (staple fixation versus self-fixating mesh) used in our field. MethodsWe designed an observational study with retrospective cohorts to analyze postoperative pain in patients who underwent a laparoscopic transabdominal preperitoneal inguinal hernia repair with a self-fixating mesh or staple fixation, which are the two available techniques in our field. A total of 296 patients who met the inclusion criteria were included between January 2014 and October 2021. ResultsThe evaluated patients’ median age was 66.0 (interquartile range (IQR): 20.75) years and were predominantly male (70.13 %). The proportion of participants with chronic pain was 3.20 % in the staple fixation group and 0 % in the self-fixating mesh group, with no statistically significant differences. On the other hand, recurrency in the staple fixation group was 2.28 % versus 3.90 % in the self-fixating mesh group, without statistically significant differences. ConclusionsSelf-fixating meshes have a trend towards smaller proportion of chronic pain and similar proportions of recurrence; therefore, they seem to be the best fixation method between the two mechanisms that are available in our field to prevent postoperative chronic pain.

The Effect of Supplementary Staple Fixation on Biomechanical Properties of Soft Tissue Graft Tibial Fixation in Anterior Cruciate Ligament Reconstruction.

This study aimed to test and compare the biomechanical properties of three tibial fixation methods of anterior cruciate ligament (ACL) tendon grafts under cyclic load and load-to-failure testing in the bovine proximal tibiae, comprising (1) staple fixation alone, (2) interference screw fixation alone, and (3) interference screw fixation with a supplementary staple. Twenty-four bovine tibiae used in the study were divided into three groups (eight proximal tibiae in each group) based on tibial fixation methods of ACL tendon grafts: group A (a spiked ligament staple alone), group B (a cannulated interference screw alone), and group C (a cannulated interference screw with a supplementary staple). Each graft fixation was exposed to cyclic loading conditions. Significant differences were determined in failure load among the three groups (p = 0.008). The mean failure load was significantly higher in group B (717.04 ± 218.51 N) than in group A (308.03 ± 17.22 N) (p = 0.006). No significant differences were observed among the groups regarding axial stiffness (p = 0.442). Cyclic displacement differed significantly among the three groups (p = 0.005). In pairwise comparisons, the mean cyclic displacement was significantly higher in group A (8.22 ± 3.24 mm) compared with group C (1.49 ± 0.41 mm) (p = 0.005). Failure displacement varied considerably among the groups (p = 0.037). Although group B (15.53 ± 6.43 mm) exhibited a greater mean failure displacement than both group A (4.9 ± 0.75 mm) and group C (8.84 ± 4.65 mm), these differences did not reach statistical significance (p = 0.602 and p = 0.329, respectively). Interference screw fixation alone and supplementary staple fixation have biomechanically similar characteristics in terms of initial strength and stiffness of tibial ACL soft tissue graft fixation. Regardless of staple use, an interference screw with the same diameter as the tibial tunnel can ensure sufficient tensile strength in tibial ACL graft fixation.

Perilunate Dislocations: Cadaveric Model K-Wire Versus Compression Staple Fixation

Repair of perilunate dislocations requires stabilization of the carpal bones, although there is limited research on the preferred method(s) of stabilization. We compared the biomechanical characteristics of K-wire versus staple fixation of scapholunate (SL) and lunotriquetral (LT) intervals in the wrist. After creating a grade IV instability model, 20 cadaver wrists were randomized into 2 stabilization model groups using K-wires or surgical staples across the SL and LT intervals. For each ligament, two K-wires or one surgical staple was used to stabilize the proximal carpal row. Each wrist was loaded with 15 N of force and cycled 5,000 times at an angular velocity of 10 rpm. Displacement between bones was measured at different cycles (10, 100, 500, 1,000, 2,000, 3,000, 4,000, and 5,000). A t test was used for comparisons. For the LT K-wire group, the average displacement at 10 cycles was 0.08 mm, and at 5,000 cycles, 0.163 mm. For the SL K-wire group, the average displacement at 10 cycles was 0.025 mm, and at 5,000 cycles, 0.129 mm. For the LT and SL staple fixation models, the average shifts at 10 cycles were 0.029 and 0.063 mm, and at 5,000 cycles, 0.098 and 0.176 mm, respectively. No significant difference between the fixation models was found at any interval. Notably, in each group, a similar number of small outliers with higher amounts of displacement was observed. Either K-wire or surgical staple stabilization is suitable for perilunate dislocations. The surgical method should be selected based on patient-specific circumstances and the provider's judgment. Therapeutic III.

Comparison between scaphotrapeziotrapezoid arthrodesis and Pyrocardan® implant for isolated scaphotrapeziotrapezoid osteoarthritis

IntroductionScaphotrapeziotrapezoid (STT) arthrodesis and Pyrocardan® implant for painful isolated STT osteoarthritis have shown good results, but no paper has compared their medium-term outcomes. HypothesesOur main hypothesis would be that the Pyrocardan® implant, by preserving the carpal biomechanics, could lead to better wrist mobility. Our secondary hypotheses would be that no other clinical and radiological differences will be found between these two procedures at a mean 5 years follow-up. PatientsIn this non-randomised retrospective study, performed at two healthcare facilities, we report and compare the outcomes of STT arthrodesis with staple fixation versus the Pyrocardan® implant in 38 patients (40 thumbs) from 2 previously published cohorts. Twenty-one patients with a mean age of 68 years (range, 46–79) underwent STT arthrodesis in facility 1. Seventeen patients with a mean age of 61 years (range, 41–80) received a Pyrocardan® implant in facility 2. Patients were reviewed at both facilities by the same examiner who performed a clinical and radiographical assessment. ResultsAt a mean follow-up of 8 years (range, 2–20 years) for the STT group and 5 years (range 3–8 years) for the Pyrocardan® group, we found no significant differences in the clinical and radiological outcomes between the two procedures except in wrist active extension and ulnar deviation, where Pyrocardan® appears to produce better mobility (extension 58°± 9 vs. 38°± 14 and ulnar deviation 35°[25, 40] versus 45°[40, 50]) (p<.001 and p<.008 respectively). The two surgical techniques led to significantly improvement in terms of pain relief, function, and strength. For the STT arthrodesis group, two complete non-unions were found (9%), while narrowing of the styloscaphoid joint space was found in eight thumbs (36%). For the Pyrocardan® group, four postoperative DISI (22%), four calcifications around the trapezium and/or distal scaphoid (22%) and one asymptomatic dislocation (6%) of the implant were observed. DiscussionPyrocardan® implant seems to result in better mobility in extension and ulnar deviation. STT arthrodesis and Pyrocardan® implant to treat isolated STT osteoarthritis led to less pain, better strength and functional scores, and restored wrist stability. A future study with a larger population will be needed to confirm these results. Level of evidenceIV.

Activated nitinol compression staples are associated with favorable biomechanical properties for talonavicular arthrodesis

BackgroundNitinol compression staple use in foot and ankle arthrodesis procedures, including for the talonavicular joint, has gained acceptance. A previous study provided evidence for using nitinol compression staples in talonavicular arthrodesis (TNA) based on functional biomechanical testing comparisons to “gold standard” lag screw fixation. This study aimed to further compare the functional biomechanical properties of nitinol compression staple fixation to lag screw fixation for arthrodesis of the talonavicular joint. Body-temperature incubation and ankle inversion and eversion loading sequences were added to previously reported biomechanical testing. MethodsRobotic testing was performed on cadaveric feet (n = 10; 5 matched pairs) after TNA using either two nitinol compression staples or two fully threaded lag screws. TNA method was randomized, alternating between matched-pairs of left and right feet. After surgical stabilization, specimens were incubated at 38 °C for 24 h to simulate the initial postoperative period in a patient. After plantarflexion and dorsiflexion testing, the specimens underwent inversion and eversion testing, cycling from 20° inversion to 10° eversion for 10 cycles. Displacements were tracked using optical tracking markers. Significant (p < 0.05) differences between staple versus screw fixation cohorts were determined using paired t-Tests. ResultsAll specimens completed testing with none experiencing failure at the TNF. No statistically significant differences in functional biomechanical testing properties were noted between nitinol compression staple fixation and lag screw fixation for TNA. ConclusionThe study findings provide additional support for nitinol compression staple fixation as an option for talonavicular arthrodesis fixation. Taken together, the results of functional biomechanical testing studies have provided sufficient evidence for initiation of a prospective clinical outcomes study using nitinol compression staples for talonavicular arthrodesis fixation at our institution.

Is fixation with a U-shaped staple necessary in anterior cruciate ligament reconstruction?

Aims: This study aimed to compare the clinical and functional outcomes of patients who underwent anterior cruciate ligament reconstruction using a quadruple hamstring autograft with and without U-shaped staple fixation and tibial tunnel BioScrew fixation. Methods: Patients who underwent arthroscopic anterior cruciate ligament (ACL) reconstruction by a single surgeon between August 2020 and June 2022 were retrospectively analyzed. The time to return to sports after surgery and the evaluation of preoperative and postoperative Lysholm Knee scores, International Knee Documentation Committee (IKDC) scores, VAS scores, and thigh diameters, were conducted. Statistical analysis of the study data was performed using SPSS 29.0 (IBM InCorp, USA). Results: A total of 100 patients (77% male) who underwent arthroscopic ACL reconstruction were included in the analysis. There was no significant difference in Lysholm knee scores and IKDC scores between patients undergoing fixation with or without staples. However, VAS scores were significantly lower in the non staple group. Conclusion: The present study found that fixation with a staple in addition to tibial BioScrew fixation of the autograft in the tibial tunnel resulted in more pain in the patients, and there was no significant difference in clinical and functional outcomes between the staple and non staple groups.

Depth variations of second and third tarsometatarsal joints during dorsal compression staple fixation using two different bridge lengths: an anatomic study

Fusion of the second and third tarsometatarsal joints is utilized for various arthritic pathologies and traumatic conditions. A cadaveric study using 20 fresh-frozen transtibial specimens were used for a stimulated arthrodesis study. Half of the specimens underwent drilling via drill guide for a respective 15 mm and 20 mm dorsal bridge length staples. Each drill guide was placed equidistant from each joint at 7.5 mm for the 15 mm bridge length and 10 m for the 20 m bridge length, then drilled bicortically in parallel with the joint line. For the 15 mm bridge length on the second metatarsal, the mean depth was 22.5 mm ± 2.2, and was 26.7 mm ± 3.8 proximal on the intermediate cuneiform. For the 20 mm bridge length on the second metatarsal, the mean depth was 22.3 mm ± 2.2 and was 27.2 mm ± 2.0 proximal on the intermediate cuneiform. For the 15 mm bridge length for the third metatarsal mean depth was 21.5 mm ± 3.2, and was 24.2 mm ± 2.9 proximal on the lateral cuneiform. For the 20 mm bridge length on the third metatarsal, the mean depth was 20.3 mm ± 2.4 and was 24.6 mm ± 2.4 proximal on the lateral cuneiform. A student's two tailed homoscedastic t-Test was calculated for the 7.5 mm vs 10 mm distal and proximal distances for both second and third TMT data sets and found there was no significant differences in depth.The current study found that for both 15 mm and 20mm bridge lengths for 2nd TMT fusions a 22 mm leg length can be used appropriate and similarly for 3rd TMT fusions, a 20 m leg length appears to be appropriate fixation. Although variations will exist, advances towards indication specific fixation may allow for varied leg length for optimal boney purchase.

Surgical planning for staple fixation of the first tarsometatarsal joint: An anatomic study

First tarsometatarsal (TMT) arthrodesis is a common procedure utilized by foot and ankle surgeons for the management of a variety of first TMT pathology including hallux valgus and arthritis. The present study was undertaken to determine the average staple leg depth that allows for adequate purchase within the medial cuneiform and first metatarsal base at 2 different staple bridge lengths for dorsal compression across the 1st TMT joint. A cadaveric study was performed using 20 fresh-frozen below knee specimens. After TMT dissection was performed, drill holes were then created from dorsal to plantar and parallel to the first TMT joint at the distances utilized for 20 mm and 25 mm staple bridge lengths. The depths of each drill hole were measured and recorded. The mean medial cuneiform depth corresponding to a 20 mm and 25 mm staple bridge was 31.9 mm +/- 2.8 mm and 31.1 mm +/- 2.1 mm respectively (P-value = 0.38). The mean first metatarsal depth corresponding to a 20 mm and 25 mm staple bridge was 27.9 mm +/- 2.2 mm and 25.4 mm +/- 3.4 mm respectively (P-value = 0.04), showing statistical significance. Based on our anatomic data it is suggested that a 20 mm staple leg depth is consistently a safe depth when using 20×20 and 25×20 mm dorsal compression staples. However, further studies must be conducted to compare the amount of compression between the two respective staples.

Comparison of Staple, Anchor, and Tenodesis Screw for Posterior Tibialis Tendon Fixation: A Biomechanical Analysis

Various posterior tibialis tendon fixation techniques are described in literature. Suture anchor, staple and tenodesis screws are widely used for posterior tibialis tendon transfer, but their stiffness and the maximal ultimate failure load were not tested before. We aimed to compare the initial ultimate failure load and stiffnesses of suture anchor, staple and tenodesis screws on bovine tendon fixation to bovine metaphyseal bone. Thirty-five fresh bovine ankle joints and hooves were obtained from a local abattoir. Metatarsals bones with long extensor tendons were harvested. Staple group had 15, suture anchor group had 10, and tenodesis screw group had 10 samples. All fixations were tested with Instron® ElectroPuls® E10000 Test Instrument. Ultimate failure load and failure location were noted. Staple group's median ultimate failure load was 210.03 N (IQR: 133.43), suture anchor group's was 124.33 N (IQR: 63.67), and tenodesis screw group's was 394.46 N (IQR:115.09). Median stiffness of the staple group was 19.87 N/m (IQR: 15.29); the tenodesis screw group's was 20.28 N/m (IQR: 6.18), the anchor group's was 8.54 N/m (IQR: 4.35). Staples' failure occurred on tendon-staple interface, while suture anchors' occurred on anchor-suture interface and tenodesis screws' occurred on tendon-suture interface. Tenodesis screws' ultimate failure load was the highest (tenodesis vs anchor and staple p < .001 and p=.032, respectively). Staple fixation is less expensive than the other methods and can provide sufficient fixation strength but was weaker than the tenodesis screw fixation. Staples are still a good choice for tendon to bone fixation, whereas the suture anchors provide lower fixation strength at a higher cost.

Fixation of transverse midshaft clavicle fractures with nitinol staples vs. superior locked plating: a biomechanical study

Background: Nitinol staples have been used effectively for stabilization and compression at fracture sites. This study compared yield load, fracture displacement, and load to failure between nitinol staples and superior plating for midshaft clavicle fractures. Methods: Ten pairs of cadaveric clavicles underwent midshaft osteotomy. Each specimen in each pair was randomly assigned to fixation with superiorly placed nitinol staples or with superior plating. Specimens were loaded cyclically with increasing loads to a maximum of 1200 cycles and 60 N. Fracture displacement and construct stiffness were compared at each load. Load to failure was performed at the conclusion of testing. Results: The staple group demonstrated lower yield load and higher median fracture displacement at all levels of force compared to the plate group. Median displacement at physiologic load was 15.3 (IQR 12.8-16.5) mm for the staple construct and 2.9 (IQR 2.5-3.6) mm for plated constructs (P=2.04E-07). Median stiffness of plated constructs was significantly higher than staple constructs at all levels (P&lt;0.05). Median cycles to failure for staple constructs was significantly lower compared to plated constructs (P=0.004). Median load to failure was significantly higher for plated constructs compared to staple constructs (P=2.8E-06). Conclusions: Nitinol staple fixation of midshaft clavicle fractures demonstrated lower yield load, stiffness, increased displacement, and lower load to failure compared to superior plate fixation. However, staple constructs provided adequate stability to maintain reduction of the fracture at physiologic levels of repetitive stress, indicating a potential role for nitinol staples in clavicle fracture fixation.

Fixation Techniques for Scaphoid Nonunion.

Scaphoid fractures are common injuries with high risk of nonunion. Various fixation techniques exist for managing scaphoid nonunions, including Kirschner wires, single or dual headless compression screws, combination fixation techniques, volar plating, and compressive staple fixation. The indication for each fixation technique varies depending on the patient, type of nonunion, and clinical scenario.

A Comparative Study of 2-Corner, 3-Corner, and 4-Corner Arthrodesis for Midcarpal Arthritis.

Four-corner fusion (4CF) is a common treatment for midcarpal arthritis; however, alternatives including 2-corner fusion (2CF) and 3-corner fusion (3CF) have been described. Limited literature suggests 2CF and 3CF may improve range of motion but have higher complication rates. Our objective is to compare function and patient-reported outcomes following 4CF, 3CF, and 2CF at our institution. Adult patients undergoing 4CF, 3CF, and 2CF from 2011 to 2021 who attended at least one follow-up were included. Four-corner fusion patients were compared with those who underwent either 3CF or 2CF using staple fixation. Outcomes include nonunion rate, reoperation rate, progression to wrist fusion, range of motion, and patient-reported pain, satisfaction, and Disabilities of the Arm, Shoulder, and Hand (DASH) scores. A total of 58 patients met inclusion criteria. There were 49 4CF and 9 2CF or 3CF patients. Nonunion rates, progression to wrist fusion, and repeat surgery for any indication were not significantly different among groups. Range of motion (flexion-extension, radial-ulnar deviation) and grip strength at postoperative visits were not significantly different. Significantly more 4CF patients required bone grafting. Pain, overall satisfaction, and DASH scores were similar. Although prior studies suggest increased risk of nonunion and hardware migration after 2CF/3CF, we did not observe higher complication rates compared with 4CF. Range of motion, strength, and patient-reported outcomes were similar. While 4CF is traditionally the procedure of choice for midcarpal fusion, we found that when using a staple fixation technique, 2CF and 3CF have comparable clinical and patient-reported outcomes yet decrease the need for autologous bone grafting.

Additional anteromedial staple fixation prevents changes in the posterior tibial slope in retrotuberosity bi-planar open-wedge high tibial osteotomy.

To compare the changes in posterior tibial slope (PTS) between retrotuberosity biplane open-wedge high tibial osteotomies (RT-OWHTOs) with and without additional anteromedial staple fixation. Seventy-nine and 77 cases of RT-OWHTOs without (Group N) and with (Group S) additional staple fixation, respectively, were retrospectively reviewed. All procedures were performed using a locking spacer plate. Demographics and preoperative knee condition were similar between the groups. Clinically, the Western Ontario and McMaster Universities Arthritis Index and range of motion were evaluated preoperatively and 2years postoperatively. Radiographically, the mechanical axis (MA), medial proximal tibial angle (MPTA), and PTS were evaluated preoperatively and within 2years postoperatively. Hinge fractures were investigated using computed tomography at 2weeks postoperatively. PTS loss was defined as the difference between the corresponding values at 2weeks and 2years postoperatively. The incidence of PTS failure (PTS loss ≥ ± 3°) was also investigated. The clinical results were not significantly different between groups N and S preoperatively and 2years postoperatively. There were no significant differences in the MA, MPTA, and PTS between the groups preoperatively and 2weeks postoperatively; changes in these variables did not differ significantly between the groups. The incidence of hinge fractures, all of which were categorized as Takeuchi type 1, did not differ significantly. PTS loss within 2years postoperatively was significantly greater in group N than in group S (1.0° vs. 0.1°; p < 0.01). The incidence of the PTS failure was 16.5% (13/79) and 2.6% (2/77) in groups N and S, respectively (p < 0.01). Additional anteromedial staple fixation could prevent changes in the PTS in RT-OWHTO. It is a simple method for preventing an increase in the PTS after RT-OWHTO. III.

OUTCOMES AND COMPLICATIONS OF MIDFOOT ARTHRODESIS IN A COHORT OF 108 PATIENTS

Midfoot arthrodesis is the conventional surgical intervention for midfoot arthritis. Arthrodesis aims to stabilise, realign and fuse the affected joints, providing patients with improved pain and function. Current research neglects the measurement of patient reported outcomes.This study aimed to investigate objective, and patient reported outcomes of midfoot arthrodesis. The secondary aim was to identify variables predicting the development of non-union.An automated search of online patient records identified 108 eligible patients (117 feet). The rates of union, re-operations, and complications were calculated using radiographs and medical records. Logistic regression was used to model variables influencing the odds of non-union. All living patients were posted a Manchester Oxford Foot Questionnaire (MOx-FQ), a patient reported outcome assessment. Pre-operative MOx-FQ results were available in a minority of cases. Students t-test was used to compare pre- and post-operative MOx-FQ scores.The rate of union achieved was 74%. The rate of re-operations was 35%. The rate of complications was 14%. Bone grafts and staple fixation independently impacted the odds of non-union. Bone grafts decreased the odds of non-union, whilst staple fixation increased the odds. This finding agrees with the opinion of other researchers.We recommend the use of bone grafts, and the avoidance of fixation with staples. Previous attempts have been made to assess patient outcomes. However, this study is the first to use the MOx-FQ, a validated questionnaire. Therefore, this study establishes a baseline for improvements in patient reported outcomes.

Long term results and patient reported outcome measures following lisfranc injuries treated with memory staple fixation

IntroductionVarious modalities of fixation have been proposed for Lisfranc injuries. Memory staple fixation offers a simple option for transarticular fixation in suitable fracture configuration with no diaphyseal extension. However there is little evidence available in the literature regarding its efficacy and patient reported outcomes. Aim of the study was to present the long term outcomes of Lisfranc injuries treated with memory staple fixation and patient reported outcomes at average follow-up of four years. MethodThis was a retrospective analysis of all the patients who underwent fixation for Lisfranc injury using shape memory alloy (Nitinol) staples from December 2010 to October 2018. Patient demography, mechanism of injury, classification of Lisfranc injury, duration of followup, complication, revision surgery, implant removal and patient reported outcomes (AOFAS midfoot score) was noted. Results31 patients satisfied the inclusion criteria. Mean age was 50 years and 17 patients were females. 54 % patients reported low to moderate energy trauma which included simple fall from standing height or twisting injury. 28 (90.3 %) had B2 type of fracture pattern. 13 had fixation with staples only, 15 with a staple and home run screw. No patient had primary fusion. One patient had superficial infection treated with antibiotics only. Three patients developed symptomatic arthritis, out of which one proceeded to fusion. Six had implant removal for hardware related symptoms. Average AOFAS midfoot score at average four years follow-up was 77.8 which are satisfactory. ConclusionThis paper highlights good outcome following memory staple fixation for Lisfranc injuries. We believe staples are more suited for the dorsal buttressing that is typically required and provide stable, reproducible fixation Our findings also suggest less need for implant removal compared to transarticular screw or plate fixation though larger studies would be required to make definitive conclusions.

Biomechanical comparison of nitinol compression staples versus fully threaded lag screws for talonavicular arthrodesis

BackgroundTalonavicular arthrodesis (TNA) is indicated for treatment of disorders that require immobilization of the hindfoot. Lag screw fixation is considered the reference standard technique for TNA. Despite consistently favorable clinical results using lag screw fixation, it is still associated with higher than desired complication and failure rates. Nitinol compression staples have been used for TNA based on potential advantages over lag screw fixation. However, functional biomechanical data comparing lag screw and nitinol compression staples for TNA are lacking. Therefore, the objective of this study was to compare nitinol compression staples to fully threaded lag screws for use in TNA with respect to their biomechanical properties during functional robotic testing. MethodsTNA was performed on cadaveric feet (n = 12; 6 matched pairs) using either two nitinol compression staples (Arthrex, Naples, FL) or two fully threaded lag screws (Arthrex, Naples, FL) in random order, alternating between paired left and right feet. After instrumentation, specimens were mounting in a robotic testing system and loaded at 89 N/sec from 30 N to 445 N for 1 min. Then, continuous compressive load of 445 N was applied while cycling from 30° plantarflexion to 15° dorsiflexion for 10 cycles. Optical tracking markers attached to the talus and navicular bone tracked displacements. Translation data were recorded along the X, Y, Z planes. Rotation data were recorded for roll, pitch, and yaw. Significant (p < 0.05) differences between fixation methods were determined using paired t-Tests for each measured variable. ResultsThere were no statistically significant differences between staples and screws for translation in X, Y, or Z planes. When comparing rotation (roll, pitch, and yaw), there were no statistically significant differences with the exception of increased roll rotation for staple fixation versus lag screw fixation during static compression testing (p = 0.009). ConclusionBased on comparison to the reference standard lag screw fixation for clinically relevant biomechanical properties measured during functional robotic testing of the hindfoot, nitinol compression staples are a viable option for talonavicular arthrodesis.

Anatomic Description of the Calcaneocuboid Joint: Implications for Staple Fixation

Understanding the anatomy of the calcaneocuboid (CCJ) remains essential when selecting staple fixation to optimize osseous purchase during rearfoot procedures. This anatomic study quantitatively describes the CCJ in relation to staple fixation sites. The calcaneus and cuboid from 10 cadavers were dissected. Widths at 5 mm and 10 mm increments away from the joint were measured in dorsal, midline, and plantar thirds of each bone. The widths between each position's 5 mm and 10 mm increments were compared using the Student's t test. The widths among the positions at both distances were compared using an ANOVA then post hoc testing. Statistical significance was set at p ≤ 0.05. The middle (23 ± 3 mm) and plantar third (18 ± 3 mm) of the calcaneus at the 10 mm interval was greater than the 5 mm interval (p=.04). At 5 mm distal to the CCJ, the dorsal third of the cuboid maintained a statistically significant greater width than the plantar third (p=.02). The 5 mm (p=.001) and 10 mm (p=.005) dorsal calcaneus widths as well as the 5 mm (p=.003) and 10 mm (p=.007) middle calcaneus widths were significantly greater than the plantar widths. This investigation supports the use of 20 mm staple 10 mm away from the CCJ in dorsal and midline orientations. Care should be taken when placing a plantar staple within 10 mm proximal to the CCJ as the legs may extend beyond the medial cortex compared to dorsal and midline placements.