Press-fit Technique Research Articles

Talar OsteoPeriostic grafting from the Iliac Crest (TOPIC) for large medial talar osteochondral defects : Operative technique.

ObjectiveProvision of a natural scaffold, good quality cells, and growth factors in order to facilitate the replacement of the complete osteochondral unit with matching talar curvature for large medial primary and secondary osteochondral defects of the talus.IndicationsSymptomatic primary and secondary medial osteochondral defects of the talus not responding to conservative treatment; anterior–posterior or medial–lateral diameter >10 mm on computed tomography (CT); closed distal tibial physis in young patients.ContraindicationsTibiotalar osteoarthritis grade III; multiple osteochondral defects on the medial, central, and lateral talar dome; malignancy; active infectious ankle joint pathology.Surgical techniqueA medial distal tibial osteotomy is performed, after which the osteochondral defect is excised in toto from the talar dome. The recipient site is microdrilled in order to disrupt subchondral bone vessels. Then, the autograft is harvested from the ipsilateral iliac crest with an oscillating saw, after which the graft is adjusted to an exact fitting shape to match the extracted osteochondral defect and the talar morphology as well as curvature. The graft is implanted with a press-fit technique after which the osteotomy is reduced with two 3.5 mm lag screws and the incision layers are closed. In cases of a large osteotomy, an additional third tubular buttress plate is added, or a third screw at the apex of the osteotomy.Postoperative managementNon-weight bearing cast for 6 weeks, followed by another 6 weeks with a walking boot. After 12 weeks, a CT scan is performed to assess consolidation of the osteotomy and the inserted autograft. The patient is referred to a physiotherapist.ResultsTen cases underwent the TOPIC procedure, and at 1 year follow-up all clinical scores improved. Radiological outcomes showed consolidation of all osteotomies and all inserted grafts showed consolidation. Complications included one spina iliaca anterior avulsion and one hypaesthesia of the saphenous nerve; in two patients the fixation screws of the medial malleolar osteotomy were removed.

A cohort comparison of humeral implant designs in reverse shoulder arthroplasty: does implant design lead to lower rates of complications and revision?

The purpose of this study was to evaluate the outcomes, revisions, and complications between a first-generation cemented modular humeral implant and a second-generation monolithic, primarily uncemented humeral implant in reverse total shoulder arthroplastywith 135° neck-shaft angle and varying degrees of metallic glenosphere offsets. We retrospectively evaluated patients undergoing reverse total shoulder arthroplasty from 2004 to 2014 with a first-generation cemented modular humeral implant (400 patients) or second-generation monolithic humeral stem (231 patients), who had at minimum 2-year clinical and radiographic follow-up. Both groups of patients had similar improvement of clinical outcomes (American Shoulder and Elbow Surgeons +30 points vs. +34 points, respectively) with improvements in all planes of motion (forward flexion +70° vs. +75°, abduction +61° vs. +71°, external rotation +23° vs. +22°, and internal rotation +1.6 vs. +1.5 level improvement, respectively). The incidence of humeral loosening for the cemented group was 3.6%, whereas in the uncemented group it was 0.4% (P = .01). A total of 28 shoulders treated with the cementing technique (4.0%) and 6 patients treated with the press-fit technique (1.5%) were revised (P = .028). The rate of postoperative acromial fractures within the first year was 3.4% in the cemented group and 1.8% in the uncemented group (P = .177). Both the first-generation cemented modular humeral stem implant and the second-generation monolithic humeral stem implant had equivalent clinical outcomes. In addition, with the monolithic stem primarily using press-fit fixation, there was a significant reduction in the incidence of radiographic loosening and the need for revision compared with a cemented stem.

Modeling of resonant magnetoelectric response in press-fit embedded ring composite

Magnetoelectric (ME) effect is a product property arising out of the interactions between the piezoelectric and the magnetostrictive phase. Multi-phase ME composites being multifunctional materials find use in myriad of applications. In this work, epoxy free two phase and three phase embedded ring ME composites have been fabricated by the press-fit technique. For a comparative study, three phase conventional epoxy bonded ring shaped composite of same dimensions have also been fabricated. Dynamic ME experiment has been conducted at room and elevated temperatures on all the prepared composites. It is shown that the epoxy free composite by virtue of the absence of epoxy shows a better resonant ME response at all temperatures. The significance of the Electromechanical Resonance (EMR) in the resonance behavior of the composites has also been highlighted. An analytical model in cylindrical coordinate system incorporating the temperature effects on the individual composite constituents and their interface coupling has been developed based on the concentric ring approach to predict the dynamic ME behavior of the epoxy free ring composite at different temperatures. The model has been further used to study the effect of volume fraction of the constituents on the ME response.

Bone-on-Bone Anatomic Patellar Tendon Graft Anterior Cruciate Ligament Reconstruction: A Reproducible Technique Combining Press-Fit and Extracortical Fixation

Scientific interest in optimizing outcomes after anterior cruciate ligament (ACL) reconstruction is ongoing, and some recent developments have focused on graft shape as one of the most important factors of anatomic graft placement. The double-bundle or fanlike structure of the native ACL seems to more closely restore normal function and control of rotational stability of the knee with implant-free or press-fit techniques, creating a favorable situation in terms of direct graft-tunnel healing. The ACL reconstruction technique presented in this article enables safe, reproducible, and anatomic fixation of the patellar tendon autograft, providing the biological and biomechanical benefits of direct bony integration of the ribbonlike bone–patellar tendon–bone graft. Because press-fit fixation represents a technically challenging surgical procedure, the goal of the described technique is to enable direct bone-to-bone healing by using secondary extracortical femoral and tibial fixation without the need for a true press-fit situation. Safe and anatomic femoral tunnel drilling is achieved with an outside-in technique (retrograde drilling), hence providing advantages in the routine clinical setting in terms of applicability and time effort. To reduce donor-site morbidity caused by bone block harvesting, refilling of the harvest sites with autologous material is performed.

Short-term evaluation of humeral stress shielding following reverse shoulder arthroplasty using press-fit fixation compared with cemented fixation

The purpose of this study was to compare the functional outcomes and humeral stress shielding of a reverse shoulder arthroplasty (RSA) placed with either cement or press-fit fixation. The hypothesis was that there would be no difference in functional outcomes or stress shielding. We performed a multicenter retrospective review of primary RSAs performed with standard-length stems. The stems were identical in geometry and coating with the only variable being whether the stems were secured with cement or by a press-fit technique. The functional outcomes and radiographs of 93 press-fit stems and 26 cemented stems were reviewed at a minimum of 2 years postoperatively. Significant improvements were noted in all ranges of motion and functional outcomes from baseline (P < .001), but no difference was found between the groups (P > .05). Calcar osteolysis was seen in 43% of press-fit and 58% of cemented stems (P = .266). Proximal lateral stress shielding was more common in the press-fit group (68%) than in the cemented group (25%) (P = .045). Adaptive changes were considered low in 97% of press-fit stems, and there were no cases of tuberosity resorption. No evidence of loosening or humeral component shift was noted in either group. At short-term follow-up, no differences in functional outcomes or stem loosening were found between press-fit fixation and cemented fixation of an RSA humeral stem. Proximal stress shielding was more common with press-fit fixation with the stem in this study, but the overall changes were considered low in 97% of cases. Further study is needed to evaluate the mid- to long-term differences regarding stress shielding.

Primary Monoblock Inset Reverse Shoulder Arthroplasty Resulted in Decreased Pain and Improved Function

The first-generation, lateral-center-of-rotation reverse shoulder arthroplasty (RSA) modular design has demonstrated durable early-, mid-, and long-term outcomes. The second-generation monoblock implant shares a similar design but eliminates the modular junction and facilitates inset placement within the metaphysis to avoid humeral-sided junctional failures and facilitate metaphyseal press-fit. However, no paper has specifically examined the radiographic findings and improvements in pain and function after the use of this next generation design. (1) After second-generation, lateral-center-of-rotation monoblock RSA, what are the improvements in shoulder scores, general health scores, and ROM at a minimum of 2 years of followup? (2) Are the differences in shoulder scores, health scores, and ROM associated with fixation (cemented versus cementless components)? (3) How frequently do complications occur (defined as humeral loosening, dislocation, baseplate failure, scapular notching, acromial fractures, and revision surgery) after inset monoblock RSA? We retrospectively studied patients undergoing primary RSA between 2010 and 2015 with preoperative data and a minimum of 2 years of clinical followup. Of the 329 primary RSA performed during this period, 125 were excluded based on the use of a different generation humeral stem of the same design, three based on need for a nickel-free implant, and 39 due to a lack of preoperative shoulder scores. Of the remaining 162 patients, 137 patients (85%) met the inclusion criteria with a mean age of 74 years (range, 46-90 years). The predominant indications were osteoarthritis with a massive rotator cuff tear (74%) and fracture sequelae (16%). During the study, humeral implants were typically inserted using an uncemented press-fit technique (85%), with only 21 patients requiring a cemented humeral stem. The mean clinical and radiographic followup period was 37 months (range, 24-82 months). Patient-reported outcome measures (PROMs) including the Simple Shoulder Test, American Shoulder and Elbow Surgeons Total, VAS for pain, SF-12, Single Assessment Numeric Evaluation, and measured active motion (forward elevation and external and internal rotation) were recorded at pre- and postoperative intervals. Postoperative radiographs were evaluated for baseplate failure, glenoid and humeral loosening, scapular notching, and acromion fractures. Complications were recorded in the longitudinally maintained institutional repository. At the most recent followup examination, there were improvements in measured motion, general health outcomes, and all PROMs. There were no differences between the cemented and press-fit techniques. Complications observed included 17 of 137 patients (12%) with scapular notching, six postoperative acromion fractures (4%), and two revision procedures (1%). No patients experienced gross humeral loosening or baseplate failure. Primary RSA using a second-generation monoblock inset humeral component resulted in improvements in pain and functional outcomes as well as low rates of acromion fractures, humeral radiolucency, and complications. Future studies are needed to provide a more definitive analysis on the use of an uncemented technique for humeral stem fixation and the effect of an inset stem on postoperative acromion fractures. Level IV, therapeutic study.

ACL reconstruction with quadriceps tendon graft and press-fit fixation versus quadruple hamstring graft and interference screw fixation \u2013 a matched pair analysis after one year follow up

BackgroundThe objective of the study was to compare the results of a primary anterior cruciate ligament reconstruction (ACLR) using the press-fit fixation technique for a quadriceps tendon (QT) graft to a standard quadrupled hamstring (HT) graft with interference screw fixation.MethodsA retrospective cohort study with a 12-month follow up provided data for 92 patients. Exclusion criteria were accompanying ligament injuries and contralateral ACL injury. Patients who suffered a graft failure, which was defined as a side-to-side difference of > 3 mm, or infection were rated ‘D’ according to the IKDC and excluded from further evaluation. Forty-six patients underwent primary ACLR using the press-fit fixation technique for autologous bone QT graft. These patients were matched in terms of age, gender, accompanying meniscus tear and cartilage injury to 46 patients who underwent standard HT graft with interference screw fixation. Patients were evaluated according to the Lachman test, Pivot-Shift test, IKDC score, Tegner score, Rolimeter measurements, one-leg hop test, thigh circumference and donor side morbidity.ResultsNo significant differences in Tegner score (p = 0.9), subjective or objective IKDC score (p = 0.9;p = 0.6), knee stability (Lachman Test p = 0.6; Pivot-Shift Test p = 0.4; Side-to-Side Difference p = 0.4), functioning testing (One-Leg Hop Test p = 0.6; Thigh Circumference p = 0.4) or donor side morbidity (p = 0.4) were observed at the follow up. The Lachman test was negative for 85% of the QT group and 83% of the HT group. The Pivot Shift Test was negative for 80% of the QT group and 85% of the HT group. The mean side-to-side difference was 1.6 ± 0 .2mm in both groups. The one-leg hop test revealed a collateral-side jumping distance of 96.2 ± 8.5% for the QT group and 95.5 ± 8.5% for the HT group. The thigh circumference of the injured leg was 98.3 ± 3.0% on the uninjured side in the QT group and 99.7 ± 3.0% in the HT group. A knee walking test resulted in no discomfort for 90% of the QT group and 85% of the HT group. The graft failure rate was 7.3% in the QT group and 9.8% in the HT group.ConclusionQT grafts fixated using the press-fit technique are a reliable alternative for primary ACL surgery.

Comparison of screw fixation versus non-fixation in dorsal opening wedge medial cuneiform osteotomy of adult acquired flatfoot

BackgroundThe aim of this study was to compare the radiographic and functional results between fixation and non-fixation in the Cotton osteotomy for the treatment of adult acquired flatfoot. MethodsA retrospective, case-controlled study of consecutive stage IIB posterior tibial tendon dysfunction (PTTD) patients treated with the same bony reconstructive surgery including cotton osteotomy between 2013 and 2017. Meary’s angle, the medial arch sag angle (MASA), and medial cuneiform cobb angle (MCCA) were evaluated pre-operation, at first weight bearing after surgery, and 12 months post operation. ResultsForty feet were included in the study. The cotton osteotomy utilized screw fixation (n = 20) or non-fixation technique (n = 20). No significant differences between groups were found in pre-operative and follow-up radiographic parameters, union rate, and functional results. ConclusionThe non-fixation with press fit technique is a reliable procedure for Cotton osteotomy and as effective as screw fixation. Level of evidenceLevel III, case control study

Value comparison of humeral component press-fit and cemented techniques in reverse shoulder arthroplasty

Press-fit humeral fixation for reverse shoulder arthroplasty (RSA) has been shown to have loosening rates and outcomes similar to a cemented technique; however, increased value has not been reported. The purpose of this study was to determine whether the press-fit technique could improve the value of RSA using the procedure value index (PVI). Primary RSA patients with complete hospitalization cost data, preoperative and minimum 2-year postoperative Simple Shoulder Test (SST) scores, and postoperative satisfaction were included. The PVI was calculated as improvement in the SST score (in units of minimal clinically important difference) divided by total cost and normalized. Itemized cost data were obtained from hospital financial records and categorized. Radiographic complications, infections, and revisions were noted. Comparisons were made between the press-fit and cemented RSA cohorts. A total of 176 primary RSA patients (83 cemented and 93 press fit) met the inclusion criteria (mean follow-up period, 44.6 months). Surgical indications (except failed rotator cuff repair), baseline SST scores, and demographic characteristics were similar. The calculated minimal clinically important difference for the SST score was 3.98. The average PVI was significantly greater in the press-fit cohort (1.51 vs 1.03, P < .001), representing a 47% difference. SST score improvement was not significantly different (P = .23). However, total hospitalization costs were significantly lower for the press-fit cohort ($10,048.89 vs $13,601.14; P < .001). Use of a press-fit technique led to a 47% increase in value over a cemented technique. This appeared to be a function of decreased total costs rather than increased outcome scores.

Long-term follow-up after anterior cruciate ligament reconstruction using a press-fit quadriceps tendon-patellar bone autograft

BackgroundThe use of a quadriceps tendon-patellar bone (QTPB) autograft provides an alternative procedure in primary reconstruction of the anterior cruciate ligament (ACL). Using the press-fit technique for femoral fixation and knotting over a bone bridge as well as additional spongiosa filling for tibial fixation can completely eliminate the need for fixation implants. The objective of this study was to evaluate the long-term clinical, functional and radiological results of this operating method.MethodsSixty-nine patients (27 female-42 male) were included in this study. Fifty-seven patients (83%) received a comprehensive follow-up review after an average period of 7.5 years (range: 7–8.7). All other patients were surveyed by telephone. Six patients (9%) suffered a re-rupture of the ACL graft caused by a new related trauma and were therefore excluded from the statistical analysis.ResultsOf all patients, 98% were satisfied with the operation. Normal or almost normal results were recorded in the subjective IKDC scores form by 88% of the patients. The Lysholm score demonstrated very good and good results in 83% of the patients. Only 1 patient reported minor complaints in the donor area. Seven (12%) patients developed Cyclops syndrome with limited knee extension. This complication was treated arthroscopically within the first year postoperatively. Their results on follow-up were not worse than the results of the patients without Cyclops syndrome.Regarding the 57 patients who received a comprehensive evaluation, the stability test with the KT-1000 Arthrometer yielded a difference of less than 3 mm in the contralateral comparison for 89% of the operated knees. The pivot-shift test was normal in 79% and almost normal in 21%. In the Single-leg Triple Hop Test, patients achieved an average of 98% of the hopping distance attained with the contralateral leg. The radiological examination revealed a slight deterioration in the Kellgren-Lawrence Score in 2 patients.ConclusionThe ACL reconstruction using the QTPB autograft performed with the press-fit technique leads to good results in comparison with published results of established procedures for primary ACL surgery using other autografts. Further investigations should involve comparative studies with the objective of providing evidence-based, individually adapted therapy for ACL rupture.

Crestal Sinus Floor Elevation with Autogenous Press-Fit Dowel Bone Harvested Using Trephine Drills: A New Method.

The aim of this study was clinical and radiographic evaluation of sinus floor lifting from the alveolar crest with trephine bur and autogenous bone graft. In this research, a press-fit dowel bone technique with application of an autogenous bone block was used for elevating the sinus floor. Ten closed sinus lift surgeries were performed on 10 patients; all patients possessed atrophic ridges in an edentulous maxilla. Bone height of the ridge ranged between 3 and 5 mm. Surgery included forming a bony cylinder with a trephine bur to reach the sinus cortical floor and then elevating the sinus floor bone with anosteotom and placing an autogenous bone block at the site and fitting it with strikes of a hand mallet. The amount of an osteotom sinus floor height gain was measured during implant placement and via radiography before surgery and four months postsurgery. Average height of the sinus floor bone after surgery was 8.33 mm with SD = 1.39 mm. Mean bone height gain after surgery in evaluated patients was 3.47 mm with SD = 1.4 mm. As a result, bone sinus floor height following surgery was significantly increased (P value = 0.044), with a significant difference between sinus floor bone height before and after surgery (P value = 0.041). No significant difference was observed between sinus floor bone height gain and sex, age, and smoking before and after the operation. The sinus floor lift method by trephine and autogenous bone graft is a practical and simple way to reduce the time needed for implantation in patients with moderate atrophy of the posterior maxilla.

Line-to-Line Reaming of Highly Porous Acetabular Components Improves Position and Reduces Variability of Component Placement

AbstractAccurate and precise acetabular component position in total hip arthroplasty remains challenging even for experienced, high-volume surgeons. Some variability may result from the press-fit technique of cementless components and maybe magnified by the use of highly porous cups with high-friction surfaces. The purpose of this study is to investigate the acetabular component positioning of a hemispherical, highly porous cup with line-to-line reaming compared with press-fit techniques. A retrospective cohort study was performed of 110 consecutive primary total hip arthroplasties performed by a single surgeon using a highly porous acetabular component. Half of the patients had the component implanted with a line-to-line reaming technique and the other half were implanted using a 1 mm press-fit technique. Postoperative radiographs were evaluated for component positioning and loosening at a minimum of 1 year postoperatively by two independent surgeons. Records were reviewed for subsequent surgery. There were no differences between the groups with respect to age, sex, body mass index, operative side, or acetabular component size. The press-fit group had an average abduction angle of 49.4 ± 5° and anteversion of 20.6 ± 7°. The line-to-line group had an average abduction angle of 45.02° [standard deviation (SD) 4.58] and anteversion of 25.42° (SD 4.44) and were statistically different from the press-fit group (p &lt; 0.01). There was significantly less variability in the line-to-line group with respect to anteversion (F-test, p &lt; 0.01) compared with the press-fit group. At most recent follow-up, there were no dislocations, revisions for any reason, or radiographic evidence of loosening in either group. Line-to-line reaming for highly porous cups can improve component positioning and reduce variability compared with press-fit techniques with no difference in fixation or other clinical outcome parameters.

A modified Matti-Russe technique of grafting scaphoid non-unions.

In treatment of scaphoid non-union bone healing requires beside vital tissue and stability, enduring compression and a good interface between the graft and scaphoid fragments. While fixation techniques show a good primary stability, they reduce sintering and thus compression of fragments in the long term. Therefore, a modified technique optimising the cancellous interface between graft and scaphoid but still providing enough stability without fixating implants should be evaluated. A corticocancellous bone graft from iliac crest was shaped ellipsoid and was implanted in a modified Matti-Russe press fit-technique. Thereby the cancellous side contacts the scaphoid fragments. In a retrospective design, we reviewed 52 patients with documented non-unions of the scaphoid. The average length of follow-up was 8.6 months. Range-of-motion, pain and grip-strength was measured and compared with contralateral wrist. Radiological assessment included beside X-rays CT scans. Results were further measured by DASH score and Mayo wrist score. The average postoperative pain was 0.9 based on NRS-Score. The mean range-of-motion was satisfactory with a dorsal-palmar arch of 115.3°, radial-ulnar: 48.2° and pro-supination: 171.3°. Mayo Wrist Score showed with 91.2 out of 100 an excellent result. The analysis of DASH score revealed a mild subjective constriction (9.2/100). Regarding roentgenographic findings complete union was confirmed in 44 of the 52 patients (84.6%). Patients with non-union were significantly older than patients with union (p < 0.05). Grip-strength on average was equal to that of the uninjured hand although in failure cases a slightly reduced grip-strength was seen. The modified technique of Matti-Russe provided a good contact of the cancellous part of the bone graft to the scaphoid in grafting a scaphoid pseudarthrosis with a high healing rate. However, since age, previous failed surgery and a proximal fracture line are the most important handicaps for bone healing in this study, for patients at risk gadolinium-enhanced MRI scan could be helpful to estimate vascularisation preoperatively. In cases of poor vitality, vascularised bone grafting should be considered.

Screws are not needed when secure interference fit of uncemented acetabular components is adequate: a 5- to 15-year follow-up with clinical and radiological analysis.

Even with good surgical preparation, adequate primary stability of the acetabular component is not always achieved after primary total hip replacement (THR). We hypothesise that adequate bone preparation for appropriate cortical loading would allow us to avoid screw use. A total of 791 uncemented cups were analysed to compare the need for screws to obtain primary fixation in 5 different designs. Arthritic hips with inflammatory arthritis or severe congenital hip disease were excluded. A press-fit technique was first tried in all hips and screws were only used when strictly needed. Radiological acetabular shape and postoperative cup position were assessed in all hips. The mean follow-up was 9.6 (5-15) years. Screws were required in 155 hips (19.6%). We could not detect any difference in the percentage of screw use between designs. We found that female patients (odds ratio [OR] 2.06; 95% confidence interval [CI], 1.41-3.02) and cups with a greater distance to the hip rotation centre on the postoperative radiograph (OR 1.69; 95% CI, 1.17-2.45) had a higher risk for screw use. A greater anteversion of the cup had a lower risk for screw use (OR 0.96; 95% CI, 0.94-0.99). At latest follow-up no hips had needed revision for aseptic loosening. Good intraoperative technique is not enough to avoid screw use since more accurate cup position and reconstruction of the hip rotation centre are required for an adequate interference fit. A press-fit technique can provide similar mid-term results to screw use in hips without severe deformities.

No Difference in Implant Micromotion Between Hybrid Fixation and Fully Cemented Revision Total Knee Arthroplasty: A Randomized Controlled Trial with Radiostereometric Analysis of Patients with Mild-to-Moderate Bone Loss.

In revision total knee arthroplasty (TKA), the femoral component and tibial baseplate are usually cemented. However, stems can be fixed either with cement or with a press-fit technique, with the latter resulting in hybrid fixation. There is no consensus on the preferred stem fixation technique. Therefore, we compared the stability of cemented TKA implants with the stability of TKA implants fixed with the hybrid technique in a prospective randomized trial using radiostereometric analysis (RSA). Thirty-two patients with a Type-I or II bone defect who needed revision TKA and were randomly allocated at the time of surgery into either the cemented or hybrid-fixation group were included in the study. The radiographs for the RSA were obtained during hospitalization (baseline); at 6 weeks; and at 3, 6, 12, and 24 months. Migration of the femoral and tibial implants was measured using model-based RSA and expressed along or around the 3 orthogonal axes and as total translation (TT) and total rotation (TR). Clinical results were evaluated using the Knee Society Score (KSS), the Knee injury and Osteoarthritis Outcome Score (KOOS), active flexion, and visual analog scale (VAS) scores for pain and satisfaction. Mann-Whitney and chi-square tests were used to compare migration and clinical outcomes between the cement and hybrid techniques. At 24 months, no difference in median migration or the number of migrating components was found between the cemented and hybrid-fixation groups. In each group, approximately one-third of the tibial components had total rotation of >1°. The clinical scores did not differ between the techniques. At 24 months after revision TKAs, cemented and hybrid-fixation replacements were equally stable. Unexpectedly, both groups had implants with >1 mm or >1° of micromotion although there were no clinical or radiographic signs of loosening. Whether these findings indicate the possibility of loosening with longer follow-up remains to be investigated. Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Hydroxyapatite in total hip arthroplasty. Our experience with a plasma spray porous titanium alloy/hydroxyapatite double-coated cementless stem

Total hip arthroplasty could fail due to many factors and one of the most common is the aseptic loosening. In order to achieve an effective osseointegration and reduce risk of lossening, the use of cemented implant, contact porous bearing surface and organic coating were developed. Aim of this study was to evaluate clinical and radiological mid-term outcomes of a porous titanium alloy/hydroxyapatite double coating manufactured cementless femoral stem applied with "plasma spray" technique and to demonstrate the possibility to use this stem in different types of femoral canals. Between January 2008 and December 2012, 240 consecutive primary total hip arthroplasties (THAs) were performed using a porous titanium alloy/hydroxyapatite double coating manufactured cementless femoral stem. 182 patients were examined: 136 were females (74.7%) and 46 males (25.2%); average age was 72 years old (ranging from 26 to 92 years old). For each patient, Harris Hip Scores (HHS) and Womac Scores were collected. All X-ray images were analyzed in order to demonstrate stem survival rate and subsidence. Harris Hip Score was good or excellent in 85% of the cases (average 90%) and mean WOMAC score was 97.5 (ranging from 73.4 to 100). No cases of early/late infection or periprosthetic fracture were noticed, with an excellent implant survival rate (100%) in a mean period of 40 months (ranging from 24 and 84 months). 5 cases presented acute implant dislocation, 2 due to wrong cup positioning in a dysplastic acetabulum and 3 after ground level fall. Dorr classification of femoral geometry was uses and the results were: 51 type A bone, 53 type B bone and 78 type C bone. Stem subsidence over 2 mm was considered as a risk factor of future implant loosening and was evidenced in 3 female patients with type C of Dorr classification. No radiolucencies signs around the proximally coated portion of stem or proximal reabsorption were visible during the radiographic follow-up. Concerning the use of porous titanium alloy/hydroxyapatite double coating, this study reported an excellent implant survival rate in a mid-term period with a rate of 1,64% of subsidence in patients with type C of femoral canal but with an optimal HHS and Womac Score results. Regarding this stem, primary stability is guaranteed by trapezoid shape of proximal region and tapering in frontal plane through press-fit technique. Radiological absence of pedestal has been accepted as sign of no excessive stress transmission to distal cortex due to its tapered diaphyseal region. Thanks to the reported data, Authors can consider this double coating a valid choice with an excellent medium-term survival and encouraging subsidence results. Further studies are needed to ensure these results can be replicated.

Clinical outcome after implant-free ACL reconstruction with hamstring tendon graft

To assess the outcome of arthroscopic anterior cruciate ligament (ACL) reconstruction with quadruple hamstring tendon graft using all press-fit technique with bone plugs near the native insertion of the ACL. This prospective study included 50 consecutive active patients. There were 47 males and 3 females. The mean age was 30 years (range 17–44). The mean follow-up was 24 months (range 12–48). Patients were evaluated using subjective as well as objective International Knee Documentation Committee (IKDC) assessment forms, Tegner Lysholm knee score. Instrumental testing included digital rolimeter as well as the KT-1000 testing. Assessment using IKDC scoring revealed that 95 % of the patients had normal or nearly normal knee (IKDC score of A/B). Postoperative level of activity was excellent in 82 % of patients. The mean side-to-side difference using the digital rolimeter measurements was 1.3 mm (range 0.1–5.5 mm). The mean side-to-side difference using the KT 1000 measurements was 1.4 mm (range 0–5 mm). On pivot shift test, we have 97 % of our patients with either equal pivot shift tests on both sides or just a glide. The mean preoperative Tegner Lysholm score was 52 (41–90) while the mean postoperative score was 92 (range 67–100). We found no graft displacement on follow-up radiographs. This study showed that arthroscopic ACL reconstruction with quadruple hamstring tendon graft using all press-fit technique with bone plugs is a reliable, cost-effective technique with fast bone-to-bone healing, and ease for revision surgery.

Sinus floor elevation with a crestal approach using a press-fit bone block: a case series

This prospective study aimed to provide detailed clinical information on a sinus augmentation procedure, i.e., transcrestal sinus floor elevation with a bone block using the press-fit technique. A bone block is harvested with a trephine burr to obtain a cylinder. This block is inserted into the antrum via a crestal approach after creation of a circular crestal window. Thirty-three patients were treated with a fixed prosthesis supported by implants placed on 70 cylindrical bone blocks. The mean bone augmentation was 6.08±2.87mm, ranging from 0 to 12.7mm. Only one graft failed before implant placement. During surgery and the subsequent observation period, no complications were recorded, one implant was lost, and no infection or inflammation was observed. This proof-of-concept study suggests that the use of a bone block inserted into the sinus cavity via a crestal approach can be an alternative to the sinus lift procedure with the creation of a lateral window. It reduces the duration of surgery, cost of treatment, and overall discomfort.

Patellofemoral Osteochondral Allograft Transplantation

Patellofemoral (PF) cartilage defects are common. They may result from instability, incongruity between the patella and trochlea, repetitive overload (microtrauma), or direct impact (macrotrauma). If exhaustive conservative management fails to resolve symptoms of disabling anterior knee pain with activities of daily living, surgical treatment may be considered. There are 3 main indications for osteochondral allograft transplantation: cartilage defects that are associated with extensive abnormalities of the subchondral bone or frank bone loss that are expected to compromise surface procedures such as autologous chondrocyte implantation; cartilage defects that are associated with severe trochlear dysplasia; and PF osteoarthritis in young patients who are not candidates for arthroplasty. Osteochondral allograft transplantation is performed using 1 of the 2 following techniques, depending on the location and extent of cartilage damage being addressed. The dowel or press-fit technique utilizes a cylindrical reamer and coring reamer system to fashion a dowel and recipient site with a diameter ranging from 15-35 mm. The shell technique is an alternative, which addresses very large defects in which the chondral defect area is removed along with bone with a saw using the same plane(s) as for prosthetic resurfacing (total knee arthroplasty or PF arthroplasty). Careful assessment of PF kinematics and anatomy (or pathokinematics and pathoantatomy) are the key to optimizing success. In light of these factors, associated procedures (such as tibial tuberosity osteotomies, medial PF ligament reconstruction, or lateral retinacular lengthening) are very common in PF cartilage repair, especially with bipolar grafts. With attention to detail and technique, successful outcomes may be achieved in many patients.

The replacement of defects in the frontal walls of the paranasal sinuses by the allotransplants

The aim of the present work were the development and clinical testing of the method for the closure of defects in the anterior wallsof the frontal and maxillary sinuses with the use of the allotransplants. We have carried out the experimental studies with the transposition of the cartilaginous allograft into the bone defect by means of the press-fit technique. Within six months after the operation, the transplantation resulted in the formation of a regenerate composed of the lamellar bone tissue. We have also undertaken the clinical testing of the method forthe closure of defects in the anterior wallsof the frontal and maxillary sinuses using the cartilaginous allograft. In all the cases, the favourable clinical outcome has been achieved as evidenced by the integrity of the restored anterior wall of the sinus.