The optimal method of
The purpose of this study was to quantify tibial tunnel enlargement at 3-, 6- and 12-months post-anterior cruciate ligament reconstruction (ACLR), and evaluate the magnitude of tunnel widening with use of a Poly (L-lactic Acid) interference screw (PLLA (Bioscrew XtraLok, Conmed, New York)) compared to a Poly (L-lactic Acid) + tricalcium phosphate interference screw (PLLA+TCP (GENESYS Matryx screw comprised of microTCP and 96L/4D PLA, Conmed, New York)). This was a prospective randomized controlled trial with two parallel groups. Eighty unilateral ACL-deficient participants awaiting ACLR surgery were recruited between 2013 and 2017 from the clinic of a sole fellowship trained orthopaedic surgeon. Patients had to be skeletally mature and less than 45 years old, with no concomitant knee ligament injuries requiring surgery, chondromalacia, or previous history of ipsilateral knee joint pathology, surgery or trauma to the knee. Participants were randomized intra-operatively into either the PLLA or PLLA+TCP tibial interference screw fixation group. Study time points were pre-, 3-, 6-, and 12-months post ACLR. Participants underwent x-rays with a 25 mm calibration ball, IKDC knee assessment, and completed the ACL-Quality of Life score (ACL-QOL) at each visit. Measurement (mm) of the most proximal and distal extents as well as the widest point of the tibial tunnel were taken using efilm (IBM Watson Health) and were standardized relative to the calibration ball. A contrast inverter was used to determine clear borders based on contrast between normal and drilled bone. In addition, a subjective evaluation of the tunnel was conducted looking for bowing of the borders of the tunnel or change in tunnel shape, categorizing the tunnel as widened or not widened. Differences between groups at each time point were evaluated using independent t-tests corrected for multiple comparisons. Tunnel width was also compared as a percentage of actual screw size at 12-months post-operative. Categorical data were compared using Fisher's Exact Test. Forty participants were randomized to each group with mean age (SD) of 29.7 (7.6) and 29.8 (9.1), for PLLA and PLLA+TCP, respectively. There were no differences between groups in age, gender or ACL-QOL. There were no differences found between groups at any time point in either tunnel width measurements or tunnel width as a percentage of actual screw size. The greatest difference between groups was noted in the measurement of the widest point on lateral x-ray view with a mean difference of 11%. Based on subjective evaluation of tunnel shape, three participants had visible widening in the PLLA group, and two in the PLLA+TCP group (p=NS). No differences in tunnel widening were identified between ACL reconstruction patients using a PLLA interference screw compared to a PLLA+TCP screw for
Traditional procedures for orthopedic total joint replacements have relied upon bone cement to achieve long-term implant fixation. This remains the gold standard in number of procedures including TKR and PKR. In many cases however, implants fixed with cement have proven susceptible to aseptic loosening and 3rd body wear concerns. These issues have led to a shift away from cement fixation and towards devices that rely on the natural osteoconductive properties of bone and the ability of porous-coated implants to initiate on-growth and in-growth at the bone interface, leading to more reliable fixation. To facilitate long-term fixation through osseointegration, several mechanical means have been utilized as supplemental mechanism to aid in stabilizing the prostheses. These methods have included integrated keels and bone screws. The intent of these components is to limit implant movement and provide a stable environment for bone ingrowth to occur. Both methods have demonstrated limitations on safety and performance including bone fracture due keel induced stresses, loosening due to inconsistent pressfit of the keel, screw-thread stripping in cancellous bone, head-stripping, screw fracture, screw loosening, and screw pullout. An alternative method of fixation utilizing blade-based anchoring has been developed to overcome these limitations. The bladed-based fixation concept consists of a titanium alloy anchor with a “T-shaped” cross-section and sharped-leading end that can be impacted directly into bone. The profile is configured to have a bladed region on the horizontal crossbar of the “T” for engagement into bone and a solid rail at the other end to mates with a conforming slot on the primary body of the prosthesis. A biased chisel tip is added to the surface of the leading blade edge to draw the bone between the anchor's horizontal surface and surface of the implant, thus generating a compressive force at the bone-to-prothesis interface. The anchoring mechanism has been successfully been integrated into the tibial tray component of a partial knee replacement; an implant component that has a clinical history of revision due to loosening. A detailed investigation into the pulloff strength, wear debris generation, compressive-force properties, and susceptibility to tibial bone fracture was carried out on the anchor technology when integrated in a standard tibial tray of a partial knee replacement. When tested in rigid polyurethane bone foam (Sawbones, Grade 15) the pulloff strength of the construct increased by 360% when utilizing the anchor. The tibial tray and anchor construct were cycled under compressive loading and demonstrated no evidence of interface corrosion or wear debris generation after 1 million cycles. In addition, the anchor mechanism was shown to generate 340N of compressive force at the tibial tray-to-bone interface when evaluated with pressure sensitive film (Fuji Prescale, Medium Grade). Finally, the ultimate compressive load to induce tibial fracture was shown to increase by 17% for the anchored tray as compared to a traditional keeled tray when tested in an anatomic tibial sawbones model; and by 19% when evaluated in human cadaveric tibias. For any figures or tables, please contact authors directly.
Introduction. Aseptic loosening is one of the highest causes for revision in total knee arthroplasty (TKA). With growing interest in anatomically aligned (AA) TKA, it is important to understand if this surgical technique affects cemented
The aim of the this study was to determine the effect of the knee flexion angle (KFA) during tibial anterior cruciate ligament (ACL) graft fixation on patient reported outcomes, graft stability, extension loss and re-operation following anatomic single-bundle ACL reconstruction. All 169 included patients (mean age 28.5 years, 65% male) were treated with anatomic single bundle ACL reconstruction using patellar tendon autograft and randomized to
Introduction. The surgical management of late PJI was usually done in two stages with the placement of a temporary cement spacer. The development of one-stage surgical care raises questions about the two-stage strategy. The objectives of this study are to identify the complications related to the presence of the cement spacer within a two-stage strategy. The septic recurrence rate is also evaluated after a minimum follow-up of two years. Material and methods. Medical files of 208 patients (101 knees and 107 hips) who underwent a two-stage revision for late PJI prosthesis infection were retrospectively reviewed. Antibiotic loaded articulated homemade cement spacers were used. Second stage was usually planned on average 4 to 6 weeks after the first stage. Patients were allowed to walk without loading. The success rate was defined as the absence of septic recurrence after a minimum follow-up of two years. Descriptive statistics and uni- and multivariate analysis were conducted. Results. The spacers were left in place for an average of 42 days for the knees and 30 days for the hips. Six patients (3%) died before performing the second stage. Hip spacers were associated with 8 fractures for only one observed in the knee (4%). Spacer dislocation (11%) was observed in 23 cases (13 for the hip and 10 for the knee respectively). Treatment failure with recurrence of the infection within 2 years was observed in 26 patients (12%). Resistance to the antibiotic present in the cement was found in one third of infectious failures. The presence of a prior cemented prosthesis was significantly associated with the presence of a germ resistant to gentamicin and the persistence of the germ at the second stage. However, it was not associated with failure at two years. Discussion. the two-stage management of PJI is associated with a non-negligible mortality rate before the second stage, rarely reported in studies. The presence of an initially cemented prosthesis is associated with the presence of germs resistant to the antibiotic contained in the cement and exposes to the persistence of the resistant germ at the second stage. Spacer fractures are observed more at the hip, but less frequently than in previous reports, while dislocations are observed at both the hip and the knee, particularly due to loss of
Hamstring grafts have been associated with reduced strength, donor site pain and muscle strains following Anterior Cruciate Ligament Reconstruction (ACLR). Traditional graft fixation methods required both semitendinosus and gracilis tendons to achieve a graft of sufficient length and diameter, but newer techniques allow for shorter, broad single tendon grafts. This study seeks to compare the outcomes between Single Tendon (ST) and Dual Tendon (DT) ACLR, given there is no prospective randomised controlled trial (RCT) in the literature comparing outcomes between these options. In this ongoing RCT: (ANZ Clinical Trials Registry ACTRN126200000927921) patients were recruited and randomised into either ST or DT groups. All anaesthetic and surgical techniques were uniform aside from graft technique and
There is no question that at some point many TKAs will be cementless-the question is when. The advantages of cementless TKA include a shorter operative time, no need for a tourniquet, more suitability for MIS, no concern for cement extrusion, and the history of THA. The concerns for cementless TKA include the history to date with cementless TKA (tibia and metal-backed patella), variable bony substrate, surgical cut precision, cost, revision concerns, and the patella (for patella component resurfacers). Cemented total knee arthroplasty remains the gold standard and has proven to provide durable results in most patients. The early experience with cementless
The purpose of this study was to determine the incidence of graft-tunnel mismatch (GTM) when performing anatomic anterior cruciate ligament reconstruction (ACLR) using bone-patella tendon-bone (BPTB) grafts and anteromedial portal drilling. Beginning in November 2018, 100 consecutive patients who underwent ACLR by two sports fellowship-trained, orthopedic surgeons using BPTB autograft and anteromedial portal drilling were prospectively identified. The BPTB graft dimensions and the femoral tunnel distance, tibial tunnel distance, intra-articular distance, and total distance were measured. Surgeons determined the depth and angle of tunnels based on the patella tendon graft length dimensions in each case. After passage of the graft, the distance from the distal graft tip to the tibial cortex aperture was measured. GTM was defined as the need for additional measures to obtain satisfactory
Anterior cruciate ligament (ACL) injuries are one of the most common ligament injury occurring in young and active individuals. Reconstruction of the torn ligament is the current standard of care. Of the many factors which determine the surgical outcome, fixation of the graft in the bony tunnels has significant role. This study compared the clinical and functional outcome in patients who underwent ACL reconstruction by standard anteromedial portal technique with single bundle hamstring graft anchored in the femoral tunnel using rigidfix and cortical button with adjustable loops. The
Introduction. Intramedullary nailing is gaining popularity for treatment of distal tibial fractures due to short operative time and minimum surgical trauma to soft tissues. Distal tibial fractures are commonly associated with concurrent fibular fractures at, above or below the level of tibial fractures. So far there is no consensus for fixation of fibular fractures. Materials and Methods. Fractures of fibula at or below the level of fracture of tibia were taken into consideration. Fractures of fibula above the tibial level were excluded because they do not add to stability of fracture fixation. Retrospective study was done and distal tibia-fibula fractures were separated into 2 groups based on whether fibula was fixed or not. Measures of angulation were obtained from radiographs taken immediately after the surgery, a second time 3 months later, and at 6-month follow-up. Results. 35 fracture of distal tibia and fibula were included in study. Fibula was not fixed in 21 cases while 14 fibular fixations were carried out either using short plates(8) or intramedullary pins(6). No significant differences were observed for malalignment in fracture of fibula at the level of tibial fractures. However for fractures of fibula at a level lower than its
Cementless femoral fixation in total knee replacement has proven to be successful in many studies. There is a recent report by Berger et al, on failure of cementless fixation in a high flexion TKR design. This was with a FiberWire material that had good ingrowth characteristics but was not ideal in terms of immediate fixation. Cementless patellar fixation to date has required a metal backed patella, which has proven to be problematic in most design. For this reason, most surgeons who resurface the patella do so with an all-polyethylene cemented design. The major controversy is cemented
Introduction. The use of cementless TKA's has been gradually increasing over the past several years given the increasing life expectancy of our patient population. Cementless TKA's have not been rapidly adopted due to the challenges and uncertainty of
Self-locking button-like fixation devices for ACL reconstruction are attracting knee surgeons' attention due to promising technical advantages: complete filling of the tunnel with graft, anatomic reconstruction (AM portal), fixation achievement even when a short tunnel is reamed, opportunity of graft re-tensioning after
The aim of this paper is to evaluate the Linvatec SE graft tensioner system in obtaining predictable initial tension during ACL reconstruction using hamstring grafts. The gracilis and semitendinosus grafts were tensioned individually prior to fixation distally to a combined tension of 80N. The knees were then cycled through full range of motion and the tension recorded at 90 degrees and in full flexion and extension. Experience on the first 22 patients indicated that 41% required 10 cycles of the knee to remove pre-conditioning and equalise tension at 80N combined, while the remaining 50% required 15 cycles. 90% reached stable tension after 15 cycles. In 54% the tension increased at full extension and graft tension was adjusted to 80N in extension to avoid overconstraining the graft. Twenty-two patients studied following this initial protocol underwent outcome assessment after minimum 6 months. Mean KT1000 arthrometry manual maximum side to side difference was 1.5mm. Femoral fixation was achieved using the Endobutton (Smith and Nephew) and
Introduction. Transportal technique of femoral drilling allows the femoral tunnel to be placed in anatomic location. The study was conducted to evaluate the orientation of ACL graft performed by two different techniques and compared to orientation of native ACL. Materials/Methods. 50 patients (Group A) underwent ACL reconstruction with transtibial technique using transfix on the femoral side and 30 patients (Group B) underwent ACL reconstruction with transportal technique using endobutton. We used quadrupled hamstrings graft and
Tibial and femoral bone tunnel widening (TW) has been observed following anterior cruciate ligament (ACL) reconstruction. We developed a χ12 mm cannulated cancellous screw (Intercondylar Ligament Screw, ICLS) for femoral fixation to reduce TW. The purpose of this study is to introduce our surgical method and its results. We employed an original ICLS system developed to reduce the needed distance between the tibial and femoral-fixation points (distance between fixation points, DbF) in ACL reconstruction. Five-strand (sometimes four or six-strand) hamstring grafts are connected to the ICLS.
Transportal technique of femoral drilling allows the femoral tunnel to be placed in anatomic location. The study was conducted to evaluate the orientation of ACL graft performed by two different techniques and compared to orientation of native ACL. 50 patients (Group A) underwent ACL reconstruction with transtibial technique using transfix on the femoral side and 30 patients (Group B) underwent ACL reconstruction with transportal technique using endobutton. We used quadrupled hamstrings graft and
Objectives. We hypothesise that a long-term bioresorbable hydrophilic silkworm silk device, the SeriACL(tm) scaffold, can support the development and remodelling of native functional ligament tissue if designed to anticipate the remodelling curve of an ACL graft. This study evaluated the SeriACL scaffold for ACL replacement in a goat model at 3, 6 and 12 months. Methods. The ACL of 43 goats was replaced in an arthroscopically assisted procedure. The ACL was excised, a guide pin driven into the femur and 6mm diameter antegrade drilling performed. The tibial tunnel was drilled under direct visualisation. The graft was anchored around a post on the femur, tensioned to 50N and cycled 30x before
[Introduction]. One of the modern design total knee arthroplasty (TKA) system, the NexGen Legacy posterior-stabilized (LPS) Flex prosthesis, has been in use at our hospital since 2001. Between 2006 and 2011, NexGen LPS-Flex primary TKA were mainly performed in combination with a cemented short-keeled minimally invasive version tibial tray (MIS tibial component) instead of the traditional NexGen stemmed tibial tray. We observed some cases required early revision of isolated tibial component in primary TKA performed in this period. Therefore, our objectives were to report the series of this revision cases and to consider this failure mechanism. [Patients & Methods]. A total of 526 primary TKAs were performed using a NexGen LPS-Flex prosthesis and MIS tibial component during five-year period at our hospital. The mean age was 74 years at the time of the index procedure. We assessed revision rate of this tibial tray in this study and described clinical course of the revision cases. We also examined the clinical and radiographic features which could be associated with the failure. [Results]. The mean duration of follow-up was 2.5 years and there were 13 knees received tibial component revision during this period. Twelve knees were diagnosed with osteoarthritis and one knee with rheumatoid arthritis. The duration between primary TKA and revision averaged at 3.3 years, and the mean age at the second procedure was 67 years. TKAs were performed without applying the tibial central extension stem in all 13 knees, and thick polyethylene insert like 17 or 20 mm were selected for seven and 14 mm for five of 13 knees, that were the typical features on the primary TKA. Postoperative course of all 13 cases was uneventful and 10 of 13 knees achieved deep knee flexion over at 125 degrees. Prerevision radiographs showed characteristic pattern with tibial tray debonding at the cement-implant interface and subsidence into varus and flexion in all 13 knees. In all cases, intraoperative findings revealed a grossly loose tibial component with most of the cement mantle still attached to the bone. No case exhibited signs of macroscopic polyethylene wear and femoral component loosening. [Discussion]. The most common reason for failure of TKA is infection followed by implant loosening, polyethylene wear, and instability. Several studies document survival rates of over 90% up to 20 years with modern TKA designs using a cemented stemmed tibial component. Although failure of the tibial component was more prevalent in some early TKA designs, in recent years, failure of